Technical Field
[0001] The present invention provides a detergent tablet comprising a compressed portion
and a non-compressed, non-encapsulating portion.
Background
[0002] Detergent compositions in tablet form are known in the art. It is understood that
detergent compositions in tablet form hold several advantages over detergent compositions
in particulate form, such as ease of handling, transportation and storage.
[0003] Detergent tablets are most commonly prepared by pre-mixing components of a detergent
composition and forming the pre-mixed detergent components into a tablet using a tablet
press. Tablets are typically formed by compression of the components of the detergent
composition into a tablet. However, the Applicant has found that some components of
a detergent composition are adversely affected by the compression pressure used to
form the tablets. These components could not previously be included in a detergent
tablet composition without sustaining a loss in performance. In some cases the components
may even have become unstable or inactive as a result of the compression.
[0004] Furthermore as the components of the detergent composition are compressed, the components
are brought into close proximity with each other. A result of the close proximity
of the components can be that certain of the components react with each other, becoming
unstable, inactive or exhausted. A solution to this problem, as seen in the prior
art, has been to separate components of the detergent composition that may potentially
react with each other when the detergent composition is compressed into tablet form.
Separation of the components has been achieved by, for example, preparing multiple-layer
tablets wherein the components that may potentially react with each other are contained
in different layers of the tablet. Multiple-layer tablets, are traditionally prepared
using multiple compression steps. Layers of the tablet that are subjected to more
than one compression step are subjected to a cumulative and potentially greater overall
compression pressure. An increase in compression pressure of the tabletting press
is known to decrease the rate of dissolution of the tablet with the effect that such
multiple layer may not dissolve satisfactorily in use.
[0005] Other methods of achieving separation of detergent components have been described.
For example EP-A 0,224,135 describes a dishwashing detergent in a form which comprises
a warm water-soluble melt, into which is pressed a cold water-soluble tablet. The
document teaches a detergent composition that consists of two parts, the first part
dissolving in the pre-rinse and the second part dissolving in the main wash of the
dishwasher.
[0006] EP-B-0,055,100 describes a lavatory block formed by combining a slow dissolving shaped
body with a tablet. The lavatory block is designed to be placed in the cistern of
a lavatory and dissolves over a period of days, preferably weeks. As a means of controlling
the dissolution of the lavatory block, the document teaches admixing one or more solubility
control agents. Examples of such solubility control agents are paradichlprobenzene,
waxes, long chain fatty acids and alcohols and esters thereof and fatty alkylamides.
Detergent tablets for use in laundry or automatic dishwashing must substantially dissolve
within one cycle of the washing or dishwashing machine, i.e. within 30 to 120 minutes.
[0007] The Applicant has found that by providing a detergent tablet comprising a compressed
portion and a non-encapsulating, non-compressed portion detergent components previously
considered to be unacceptable for detergent tablets, can be incorporated into a detergent
tablet. In addition, potentially reactive components of the detergent composition
can be effectively separated.
[0008] A further advantage of using a detergent tablet as described herein, is the performance
benefits which may be achieved in being able to prepare the detergent tablet so that
if required, the compressed portion and the non-compressed portion have different
rates of dissolution. Such performance benefits are achieved by selectively delivering
active detergent components into the wash solution at different times.
Summary of the Invention
[0009] According to the present invention there is provided a detergent tablet comprising:
(a) a compressed portion comprising an active detergent component; and
(b) a non-compressed, non-encapsulating portion comprising an active detergent component,
wherein the detergent tablet comprises an enzyme.
[0010] In an alternative embodiment there is also provided a detergent tablet comprising:
(a) a compressed portion comprising an active detergent component; and
(b) a non-compressed, non-encapsulating portion comprising an active detergent component,
wherein the weight ratio of compressed to non-compressed portion is greater than 0.5:1
and the detergent tablet comprises silicate.
[0011] In another alternative embodiment there is provided a detergent tablet comprising:
(a) a compressed portion comprising an active detergent component; and
(b) a non-compressed, non-encapsulating portion comprising an active detergent component,
wherein the weight ratio of compressed to non-compressed portion is greater than 0.5:1
and the detergent tablet has a dissolution rate of greater than 0.33 g/min as determined
using the SOTAX dissolution test method described herein.
[0012] In yet another alternative embodiment there is provided a detergent tablet comprising:
(a) a compressed portion comprising an active detergent component; and
(b) a non-compressed, non-encapsulating portion comprising an active detergent component,
wherein the weight of the detergent tablet is less than 40g and the detergent tablet
has a dissolution rate of greater than 0.33 g/min as determined using the SOTAX dissolution
test method described herein.
[0013] In yet another alternative embodiment there is provided a detergent tablet comprising:
(a) a compressed portion comprising an active detergent component; and
(b) a non-compressed, non-encapsulating portion comprising an active detergent component
wherein the compressed portion provides a mould to accommodate the non-compressed
portion.
[0014] In addition there is also provided a process for preparing the detergent tablets
described herein.
Detailed Description of the Invention
[0015] Thus, in accordance with the present invention it has been found that active detergent
components of a detergent tablet previously adversely affected by the compression
pressure used to form the tablets can now be included in a detergent tablet. Examples
of these components include bleaching agents and enzymes. In addition, in accordance
with the present invention, it has been found that active detergent components of
a detergent tablet may be separated from one another by having one or more compatible
components contained in a compressed portion and one or more compatible components
contained in a non-compressed portion of the tablet. Examples of components that may
interact and may therefore require separation include bleaching agents, bleach activators
or catalyst and enzymes; bleaching agents and bleach catalysts or activators; bleaching
agents and surfactants; alkalinity sources and enzymes.
[0016] Furthermore, it may be advantageous to provide the compressed and the non-compressed
portions such that they dissolve in wash water with different dissolution rates. By
controlling the rate of dissolution of each portion relative to one another, and by
selection of the active detergent components in the respective portions, their order
of release into the wash water can be controlled and the cleaning performance of the
detergent tablet may be improved. For example it is often preferred that enzymes are
delivered to the wash prior to bleaching agent and/or bleach activator. It may also
be preferred that a source of alkalinity is released into the wash water more rapidly
than other components of the detergent tablet. It is also envisaged that it may be
advantageous to prepare a detergent tablet according to the present invention wherein
the release of certain components of the tablet is delayed relative to other components.
[0017] It is also envisaged that the tablet may comprise a plurality of compressed or non-compressed
portions. For example, a plurality of compressed portions may be arranged in layers
and/or a plurality of non-compressed portions may be present as discrete sections
of the tablet separated by a compressed portion. Thus, there may be a first and a
second and optional subsequent compressed and/or non-compressed portions, each comprising
an active detergent component and where at least the first and second portions may
comprise different active detergent components or mixtures of components. Such a plurality
of compressed or non-compressed portions may be advantageous, enabling a tablet to
be produced which has for example, a first and second and optional subsequent portions
so that they have different rates of dissolution. Such performance benefits are achieved
by selectively delivering active detergent components into the wash water at different
times.
[0018] The detergent tablets described herein are preferably between 15g and 100g in weight,
more preferably between 18g and 80g in weight, even more preferably between 20g and
60g in weight. The detergent tablet described herein that are suitable for use in
automatic dishwashing methods are most preferably between 20g and 40g in weight Detergent
tablets suitable for use in fabric laundering methods are most preferably between
40g and 100g, more preferably between 40g and 80g, most preferably between 40g and
65g in weight. The weight ratio of compressed portion to non-compressed portion is
generally greater than 0.5:1, preferably greater than 1:1, more preferably greater
than 2:1, even more preferably greater than 3:1 or even 4:1, most preferably at least
5:1.
[0019] The detergent tablets described herein have Child Bite Strength (CBS) which is generally
greater than 10Kg, preferably greater than 12Kg, most preferably greater than 14Kg.
CBS is measured as per the U.S. Consumer Product Safety Commission Test Specification.
[0020] Child Bite Strength Test Method: According to this method the tablet is placed horizontally between two strips/plates
of metal. The upper and lower plates are hinged on one side, such that the plates
resemble a human jaw. An increasing downward force is applied to the upper plate,
mimicking the closing action of the jaw, until the tablet breaks. The CBS of the tablet
is a measure of the force in Kilograms, required to break the tablet.
[0021] The detergent tablets described herein generally have a dissolution rate of faster
than 0.33 g/min, preferably faster than 0.5 g/min, more preferably faster than 1.00
g/min, even more preferably faster than 2.00 g/m, most preferably faster than 2.73
g/min. Dissolution rate is measured using the SOTAX dissolution test method. For the
purposes of the present invention dissolution of detergent tablets is achieved using
a SOTAX (tradename) machine; model number AT7 available from SOTAX.
[0022] SOTAX Dissolution Test Method: The SOTAX machine consists of a temperature controlled waterbath with lid. 7 pots
are suspended in the water bath. 7 electric stirring rods are suspended from the underside
of the lid, in positions corresponding to the position of the pots in the waterbath.
The lid of the waterbath also serves as a lid on the pots.
[0023] The SOTAX waterbath is filled with water and the temperature gauge set to 50°C. Each
pot is then filled with 1 litre of deionised water and the stirrer set to revolve
at 250rpm. The lid of the waterbath is closed, allowing the temperature of the deionised
water in the pots to equilibrate with the water in the waterbath for 1 hour.
[0024] The tablets are weighed and one tablet is placed in each pot, the lid is then closed.
The tablet is visually monitored until it completely dissolves. The time is noted
when the tablet has completely dissolved. The dissolution rate of the tablet is calculated
as the average weight (g) of tablet dissolved in deionised water per minute.
Compressed portion
[0025] The compressed portion of the detergent tablet comprises at least one active detergent
component but may comprise a mixture of more than one active detergent components,
which are compressed. Any detergent tablet component conventionally used in known
detergent tablets is suitable for incorporation into the compressed portion of the
detergent tablets of this invention. Suitable active detergent components are described
hereinafter. Preferred active detergent components include builder compound, surfactant,
bleaching agent, bleach activator, bleach catalyst, enzyme and an alkalinity source.
[0026] Active detergent component(s) present in the compressed layer may optionally be prepared
in combination with a carrier and/or a binder for example water, polymer (e.g. PEG),
liquid silicate. The active detergent components are preferably prepared in particulate
form (i.e. powder or granular form) and may be prepared by any known method, for example
conventional spray drying, granulation or agglomeration. The particulate active detergent
component(s) are then compressed using any suitable equipment suitable for forming
compressed tablets, blocks, bricks or briquettes; described in more detail hereafter.
Non-Compressed. Non-Encapsulating Portion
[0027] The non-compressed, non-encapsulating portion (hereinafter non-compressed portion)
comprises at least one active detergent component, but may comprise a mixture of more
than one active detergent components. Active detergent components suitable for incorporation
in the non-compressed portion include components that interact with one or more detergent
components present in the compressed portion. In particular, preferred components
of the non-compressed portion are those that are adversely affected by compression
pressure of for example a compression tablet press. Examples of such active detergent
components include, but are not limited to, surfactant, bleaching agent, bleach activator,
bleach catalyst, enzyme, corrosion inhibitor, perfume and an alkalinity source. These
components are described in more detail below. The active detergent component(s) may
be in any form for example particulate (i.e. powder or granular), gel or liquid form.
The non-compressed portion in addition to comprising an active detergent component,
may also optionally comprise a carrier component. The active detergent component may
be present in the form of a solid, gel or liquid, prior to combination with a carrier
component.
[0028] The non-compressed portion of the detergent tablet may be in solid, gel or liquid
form.
[0029] The detergent tablet of the present invention requires that the non-compressed portion
be delivered to the compressed portion such that the compressed portion and non-compressed
portion contact each other. The non-compressed portion may be delivered to the compressed
portion in solid or flowable form. Where the non-compressed portion is in solid form,
it is pre-prepared, optionally shaped and then delivered to the compressed portion.
The non-compressed portion is then affixed to a pre-formed compressed portion, for
example by adhesion or by insertion of the non-compressed portion to a co-operating
surface of the compressed portion.
[0030] Preferably the compressed portion comprises a pre-prepared depression or mould into
which the non-compressed portion is delivered.
[0031] The non-compressed portion is preferably delivered to the compressed portion in flowable
form. The non-compressed portion is then affixed to the compressed portion for example
by adhesion, by forming a coating over the non-compressed layer to secure it to the
compressed portion, or by hardening, for example (i) by cooling to below the melting
point where the flowable composition becomes a solidified melt; (ii) by evaporation
of a solvent; (iii) by crystallisation; (iv) by polymerisation of a polymeric component
of the flowable non-compressed portion; (v) through pseudo-plastic properties where
the flowable non-compressed portion comprises a polymer and shear forces are applied
to the non-compressed portion; (vi) combining a binding agent with the flowable non-compressed
portion. In an alternative embodiment the flowable non-compressed portion may be an
extrudate that is affixed to the compressed portion by for example any of the mechanism
described above or by expansion of the extrudate to the parameters of a mould provided
by the compressed portion.
[0032] Preferably the compressed portion comprises a pre-prepared depression or mould (hereafter
referred to as 'mould') into which the non-compressed portion is delivered. In an
alternative embodiment the surface of the compressed portion comprises more than one
mould into which the non-compressed portion may be delivered. The mould(s) preferably
at least partially accommodates one or more non-compressed portions. The non-compressed
portion(s) is then delivered into the mould and affixed to the compressed portion
as described above.
[0033] The non-compressed portion may comprise particulates. The particulates may be prepared
by any known method, for example conventional spray drying, granulation, encapsulation
or agglomeration. Particulates may be affixed to the compressed portion by incorporating
a binding agent or by forming a coating layer over the non-compressed portion.
[0034] Where the detergent tablet comprises more than one non-compressed portion, the first
and second and optional subsequent non-compressed portions may comprise particulates
having substantially different average particle size. By substantially different average
particle size we mean that the difference between the average particle size of the
first and second and/or subsequent compositions is greater than 5%, preferably greater
than 10%, more preferably greater than 15% or even 20% of the smaller average particle
size.
[0035] The average particle size of the particulate detergent active components used herein
is calculated using a series of Tyler sieves. The series consists of a number of sieves
each having a different aperture size. Samples of a composition of active detergent
components are sieved through the series of sieves (typically 5 sieves). The weight
of a sample of composition retained in the sieve is plotted against the aperture size
of the sieve. The average particle size of the composition is defined as the aperture
size through which 50% by weight of the sample of composition would pass.
[0036] In another embodiment the first and second and optional subsequent compositions of
active detergent components have substantially different density such that the difference
between the density of the first and second and/or subsequent compositions is greater
than 5%, preferably greater than 10%, more preferably greater than 15% or even 20%
of the smaller density. Density of the particulate composition of active detergent
components can be measured by any known method suitable for measuring density of particulate
material.
[0037] Preferably the density of the composition of active detergent components is measured
using a simple funnel and cup device consisting of a conical funnel moulded rigidly
on a base and provided with a flap valve at its lower extremity to allow the contents
of the funnel to be emptied into an axially aligned cylindrical cup disposed below
the funnel. The funnel is 130 mm high and has internal diameters of 130 mm and 40
mm at its respective upper and lower extremities. It is mounted so that the lower
extremity is 140 mm above the upper surface of the base. The cup has an overall height
of 90 mm, an internal height of 87 mm and an internal diameter of 84 mm. Its nominal
volume is 500 ml.
[0038] A density measurement is taken by hand pouring the composition into the funnel. Once
the funnel is filled, the flap valve is opened and powder allowed to run through the
funnel, overfilling the cup. The filled cup is removed from the frame and excess powder
removed from the cup by passing a straight edged implement e.g. a knife, across its
upper edge. The filled cup is then weighed and the value obtained for the weight of
powder doubled to provide a bulk density in grams/litre. Replicate measurements are
made as required.
[0039] Tablets in which one or more of the non-compressed portions comprise particulates
and the average particle size and/or density of the first and second and optionally
subsequent non-compressed portions are substantially different are preferred where
the first and second and optionally subsequent non-compressed portions are required
to have different rates of dissolution.
[0040] Where the non-compressed portion comprises a solidified melt, the melt is prepared
by heating a composition comprising a detergent active component and optional carrier
component(s) to above its melting point to form a flowable melt. The flowable melt
is then poured into a mould and allowed to cool. As the melt ccols it becomes solid,
taking the shape of the mould at ambient temperature. Where the composition comprises
one or more carrier components, the carrier component(s) may be heated to above their
melting point, and then an active detergent component may be added. Carrier components
suitable for preparing a solidified melt are typically non-active components that
can be heated to above melting point to form a liquid and cooled to form an intermolecular
matrix that can effectively trap active detergent components. A preferred non-active
carrier component is an organic polymer that is solid at ambient temperature. Preferably
the non-active detergent components is polyethylene glycol (PEG). The compressed portion
of the detergent tablet preferably provides a mould to accommodate the melt.
[0041] The flowable non-compressed portion may be in a form comprising a dissolved or suspended
active detergent component. The flowable non-compressed portion may harden over time
to form a solid, semi solid or highly viscous liquid non-compressec portion by any
of the methods described above. In particular, the flowable non-compressed portion
may harden by evaporation of a solvent. Solvents suitable for use herein may include
any known solvent in which a binding agent is soluble. Preferred solvents may be polar
or non-polar and may include water, alcohol, (for example ethanol, acetone) and alcohol
derivatives. In an alternative embodiment more than one solvent may be used.
[0042] The flowable non-compressed portion may comprise one or more binding agents. Any
binding agent that has the effect of causing the composition to become solid, semi-solid
or highly viscous over time is envisaged for use herein. Although not wishing to be
bound by theory, it is believed that mechanisms by which the binding agent causes
a non-solid composition to become solid, semi-solid or highly viscous include: chemical
reaction (such as chemical cross linking), or effect interaction between two or more
components of the flowable compositions either; chemical or physical interaction of
the binding agent with a component of the composition. Preferred binding agents include
a sugar/gelatine combination, starch, glycerol and organic polymers. The sugar may
be any monosaccharide (e.g. glucose), disaccharide (e.g. sucrose or maltose) or polysaccharide.
The most preferred sugar is commonly available sucrose. For the purposes of the present
invention type A or B gelatine may be used, available from for example Sigma. Type
A gelatine is preferred since it has greater stability in alkaline conditions in comparison
to type B. Preferred gelatine also has a bloom strength of between 65 and 300, most
preferably between 75 and 100. Preferred organic polymers include polyethylene glycol
(PEG) of molecular weight from 500 to 10,000, preferably from 750 to 8000, most preferably
from 1000 to 6000 available from Hoechst.
[0043] Where the non-compressed portion is an extrudate, the extrudate is prepared by premixing
the active detergent components with optional carrier components to form a viscous
paste. The viscous paste is then extruded using any suitable commonly available extrusion
equipment such as for example a single or twin screw extruder available from for example
APV Baker, Peterborough, U.K. The extrudate is then cut to size either after delivery
to the compressed portion, or prior to delivery to the compressed portion of the detergent
tablet. The compressed portion of the tablet preferably comprises a mould into which
the extruded non-compressed portion may be delivered.
[0044] In a preferred embodiment the non-compressed portion is coated with a coating layer.
The coating may be used to affix a non-compressed portion to the compressed portion.
This may be particularly advantageous where the non-compressed portion comprises flowable
particulates, gels or liquids.
[0045] The coating layer preferably comprises a material that becomes solid on contacting
the compressed and/or the non-compressed portions within preferably less than 15 minutes,
more preferably less than 10 minutes, even more preferably less than 5 minutes, most
preferably less than 60 seconds. Preferably the coating layer is water-soluble. Preferred
coating layers comprise materials selected from the group consisting of fatty acids,
alcohols, diols, esters and ethers, adipic acid, carboxylic acid, dicarboxylic acid,
polyvinyl acetate (PVA), polyvinyl pyrrolidone (PVP), polyacetic acid (PLA), polyethylene
glycol (PEG) and mixtures thereof. Preferred carboxylic or dicarboxylic acids preferably
comprise an even number of carbon atoms. Preferably carboxylic or dicarboxylic acids
comprise at least 4, more preferably at least 6, even more preferably at least 8 carbon
atoms, most preferably between 8 and 13 carbon atoms. Preferred dicarboxylic acids
include adipic acid, suberic acid, azelaic acid, subacic acid, undecanedioic acid,
dodecandioic acid, tridecanedioic and mixtures thereof. Preferred fatty acids are
those having a carbon chain length of from C12 to C22, most preferably from C18 to
C22. The coating layer may also preferably comprise a disrupting agent. Where present
the coating layer generally present at a level of at least 0.05%, preferably at least
0.1%, more preferably at least 1%, most preferably at least 2% or even at least 5%
of the detergent tablet.
[0046] As an alternative embodiment the coating layer may encapsulate the detergent tablet.
In this embodiment the coating layer is present at a level of at least 4%, more preferably
at least 5%, most preferably at least 10% of the detergent tablet.
[0047] In a preferred embodiment the compressed and/or non-compressed portions and/or coating
layer additionally comprise a disrupting agent. The disrupting agent may be a disintegrating
or effervescing agent. Suitable disintegrating agents include agents that swell on
contact with water or facilitated water influx and/or efflux by forming channels in
compressed and/or non-compressed portions . Any known disintegrating or effervescing
agent suitable for use in laundry or dishwashing applications is envisaged for use
herein. Suitable disintegrating agent include starch, starch derivatives, alginates,
carboxymethylcellulose (CMC), CMC-based polymers, sodium acetate, aluminium oxide.
Suitable effervescing agents are those that produce a gas on contact with water. Suitable
effervesing agents may be oxygen, nitrogen dioxide or carbon dioxide evolving species.
Examples of preferred effervesing agents may be selected from the group consisting
of perborate, percarbonate, carbonate, bicarbonate and carboxylic acids such as citric
or maleic acid.
[0048] An advantage of including a disrupting agent in the detergent tablet of the present
invention is the transport, storage and handling benefits that can be achieved by
increasing the hardness of the detergent tablet without adversely affecting the cleaning
performance.
Process
[0049] According to the present invention there is also provided a process for preparing
a detergent tablet comprising the steps of:
a) compressing an active detergent component to form a compressed portion; and
b) delivering a non-compressed, non-encapsulating portion comprising an active detergent
component to the compressed portion.
[0050] As described above, the detergent tablets described herein are prepared by separately
preparing the composition of active detergent components forming the respective compressed
portion and the non-compressed portion, then delivering or adhering the composition
of the non-compressed portion to the compressed portion.
[0051] The compressed portion is prepared by obtaining at least one active detergent component
and optionally premixing with carrier components. Any pre-mixing will be carried out
in a suitable mixer; for example a pan mixer, rotary drum, vertical blender or high
shear mixer. Preferably dry particulate components are admixed in a mixer, as described
above, and liquid components are applied to the dry particulate components, for example
by spraying the liquid components directly onto the dry particulate components. The
resulting composition is then formed into a compressed portion in a compression step
using any known suitable equipment. Preferably the composition is formed into a compressed
portion using a tablet press, wherein the tablet is prepared by compression of the
composition between an upper and a lower punch. In a preferred embodiment of the present
invention the composition is delivered into a punch cavity of a tablet press and compressed
to form a compressed portion using a pressure of preferably greater than 6.3KN/cm
2, more preferably greater than 9KN/cm
2, most preferably greater than 14.4KN/cm
2.
[0052] In order to form a preferred tablet of the invention, wherein the compressed portion
provides a mould to receive the non-compressed portion, the compressed portion is
prepared using a modified tablet press comprising modified upper and/or lower punches.
The upper and lower punches of the modified tablet press are modified such that the
compressed portion provides one or more indentations which form a mould(s) to which
the non-compressed portion is delivered.
[0053] The non-compressed portion comprises at least one active detergent component. Where
the non-compressed portion comprises more than one active detergent component the
components are pre-mixed using any known suitable mixing equipment. In addition the
non-compressed portion may optionally comprise a carrier with which the active detergent
components are combined. The non-compressed portion may be prepared in solid or flowable
form. Once prepared the composition is delivered to the compressed portion. The non-compressed
portion may be delivered to the compressed portion by manual delivery or using a nozzle
feeder or extruder. Where the compressed portion comprises a mould, the non-compressed
portion is preferably delivered to the mould using accurate delivery equipment, for
example a nozzle feeder, such as a loss in weight screw feeder available from Optima,
Germany or an extruder.
[0054] Where the flowable non-compressed portion is in particulate form the process comprises
delivering a flowable non-compressed portion to the compressed portion in a delivery
step and then coating at least a portion of the non-compressed portion with a coating
layer such that the coating layer has the effect of substantially adhering the non-compressed
portion to the compressed portion.
[0055] Where the flowable non-compressed portion is affixed to the compressed portion by
hardening, the process comprises a delivery step in which the flowable non-compressed
portion is delivered to the compressed portion and a subsequent conditioning step,
wherein the non-compressed portion hardens. Such a conditioning step may comprise
drying, cooling, binding, polymerisation etc. of the non-compressed portion, during
which the non-compressed portion becomes solid, semi-solid or highly viscous. Heat
may be used in a drying step. Heat, or exposure to radiation may be used to effect
polymerisation in a polymerisation step.
[0056] It is also envisaged that the compressed portion may be prepared having a plurality
of moulds. The plurality of moulds are then filled with a non-compressed portion.
It is also envisaged that each mould can be filled with a different non-compressed
portion or alternatively, each mould can be filled with a plurality of different non-compressed
portions.
Active Detergent Components
[0057] The compressed portion of the detergent tablets described herein are prepared by
compression composition of active detergent components. A suitable composition may
include a variety of different detergent active components including builder compounds,
surfactants, enzymes, bleaching agents, alkalinity sources, colourants, perfume, lime
soap dispersants, organic polymeric compounds including polymeric dye transfer inhibiting
agents, crystal growth inhibitors, heavy metal ion sequestrants, metal ion salts,
enzyme stabilisers, corrosion inhibitors, suds suppressers, solvents, fabric softening
agents, optical brighteners and hydrotropes.
[0058] Highly preferred active detergent components include a builder compound, a surfactant,
an enzyme and a bleaching agent.
Builder compound
[0059] The detergent tablets of the present invention preferably contain a builder compound,
typically present at a level of from 1% to 80% by weight, preferably from 10% to 70%
by weight, most preferably from 20% to 60% by weight of the composition of active
detergent components.
Water-soluble builder compound
[0060] Suitable water-soluble builder compounds include the water soluble monomeric polycarboxylates,
or their acid forms, homo or copolymeric polycarboxylic acids or their salts in which
the polycarboxylic acid comprises at least two carboxylic radicals separated from
each other by not more that two carbon atoms, carbonates, bicarbonates, borates, phosphates,
and mixtures of any of the foregoing.
[0061] The carboxylate or polycarboxylate builder can be monomeric or oligomeric in type
although monomeric polycarboxylates are generally preferred for reasons of cost and
performance.
[0062] Suitable carboxylates containing one carboxy group include the water soluble salts
of lactic acid, glycolic acid and ether derivatives thereof. Polycarboxylates containing
two carboxy groups include the water-soluble salts of succinic acid, malonic acid,
(ethylenedioxy) diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic
acid and fumaric acid, as well as the ether carboxylates and the sulfinyl carboxylates.
Polycarboxylates containing three carboxy groups include, in particular, water-soluble
citrates, aconitrates and citraconates as well as succinate derivatives such as the
carboxymethyloxysuccinates described in British Patent No. 1,379,241, lactoxysuccinates
described in British Patent No. 1,389,732, and aminosuccinates described in Netherlands
Application 7205873, and the oxypolycarboxylate materials such as 2-oxa-1,1,3-propane
tricarboxylates described in British Patent No. 1,387,447.
[0063] Polycarboxylates containing four carboxy groups include oxydisuccinates disclosed
in British Patent No. 1,261,829, 1,1,2,2-ethane tetracarboxylates .1,3,3-propane tetracarboxylates
and 1,1,2,3-propane tetracarboxylates. Polycarboxylates containing sulfo substituents
include the sulfosuccinate derivatives disclosed in British Patent Nos. 1,398,421
and 1,398,422 and in U.S. Patent No. 3,936,448, and the sulfonated pyrolysed citrates
described in British Patent No, 1,439,000.
[0064] Alicyclic and heterocyclic polycarboxylates include cyclopentane-cis,cis,cis-tetracarboxylates,
cyclopentadienide pentacarboxylates, 2,3,4,5-tetrahydrofuran - cis, cis, cis-tetracarboxylates,
2,5-tetrahydrofuran - cis - dicarboxylates, 2,2,5,5-tetrahydrofuran - tetracarboxylates,
1,2,3,4,5,6-hexane - hexacarboxylates and carboxymethyl derivatives of polyhydric
alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include
mellitic acid, pyromellitic acid and the phthalic acid derivatives disclosed in British
Patent No. 1,425,343.
[0065] Of the above, the preferred polycarboxylates are hydroxycarboxylates containing up
to three carboxy groups per molecule, more particularly citrates.
[0066] The parent acids of the monomeric or oligomeric polycarboxylate chelating agents
or mixtures thereof with their salts, e.g. citric acid or citrate/citric acid mixtures
are also contemplated as useful builder components.
[0067] Borate builders, as well as builders containing borate-forming materials that can
produce borate under detergent storage or wash conditions can also be used but are
not preferred at wash conditions less that 50°C, especially less than 40°C.
[0068] Examples of carbonate builders are the alkaline earth and alkali metal carbonates,
including sodium carbonate and sesqui-carbonate and mixtures thereof with ultrafine
calcium carbonate as disclosed in German Patent Application No. 2,321,001 published
on November 15, 1973.
[0069] Highly preferred builder compounds for use in the present invention are water-soluble
phosphate builders. Specific examples of water-soluble phosphate builders are the
alkali metal tripolyphosphates, sodium, potassium and ammonium pyrophosphate, sodium
and potassium and ammonium pyrophosphate, sodium and potassium orthophosphate, sodium
polymeta/phosphate in which the degree of polymerisation ranges from 6 to 21, and
salts of phytic acid.
[0070] Specific examples of water-soluble phosphate builders are the alkali metal tripolyphosphates,
sodium, potassium and ammonium pyrophosphate, sodium and potassium and ammonium pyrophosphate,
sodium and potassium orthophosphate, sodium polymeta/phosphate in which the degree
of polymerization ranges from 6 to 21, and salts of phytic acid.
Partially soluble or insoluble builder compound
[0071] The detergent tablets of the present invention may contain a partially soluble or
insoluble builder compound. Partially soluble and insoluble builder compounds are
particularly suitable for use in tablets prepared for use in laundry cleaning methods.
Examples of partially water soluble builders include the crystalline layered silicates
as disclosed for example, in EP-A-0164514, DE-A-3417649 and DE-A-3742043. Preferred
are the crystalline layered sodium silicates of general formula
NaMSi
xO
2+1 .
yH
2O
wherein M is sodium or hydrogen, x is a number from 1.9 to 4 and y is a number from
0 to 20. Crystalline layered sodium silicates of this type preferably have a two dimensional
'sheet' structure, such as the so called δ-layered structure, as described in EP 0
164514 and EP 0 293640.
Methods for preparation of crystalline layered silicates of this type are disclosed
in DE-A-3417649 and DE-A-3742043. For the purpose of the present invention, x in the
general formula above has a value of 2,3 or 4 and is preferably 2.
[0072] The most preferred crystalline layered sodium silicate compound has the formula δ-Na
2Si
2O
5, known as NaSKS-6 (trade name), available from Hoechst AG.
[0073] The crystalline layered sodium silicate material is preferably present in granular
detergent compositions as a particulate in intimate admixture with a solid, water-soluble
ionisable material as described in PCT Patent Application No. WO92/18594. The solid,
water-soluble ionisable material is selected from organic acids, organic and inorganic
acid salts and mixtures thereof, with citric acid being preferred.
[0074] Examples of largely water insoluble builders include the sodium aluminosilicates.
Suitable aluminosilicates include the aluminosilicate zeolites having the unit cell
formula Na
z[(AlO
2)
z(SiO
2)
y]. xH
2O wherein z and y are at least 6; the molar ratio of z to y is from 1.0 to 0.5 and
x is at least 5, preferably from 7.5 to 276, more preferably from 10 to 264. The aluminosilicate
material are in hydrated form and are preferably crystalline, containing from 10%
to 28%, more preferably from 18% to 22% water in bound form.
[0075] The aluminosilicate zeolites can be naturally occurring materials, but are preferably
synthetically derived. Synthetic crystalline aluminosilicate ion exchange materials
are available under the designations Zeolite A, Zeolite B, Zeolite P, Zeolite X, Zeolite
HS and mixtures thereof.
[0076] A preferred method of synthesizing aluminosilicate zeolites is that described by
Schoeman et al (published in Zeolite (1994) 14(2), 110-116), in which the author describes
a method of preparing colloidal aluminosilicate zeolites. The colloidal aluminosilicate
zeolite particles should preferably be such that no more than 5% of the particles
are of size greater than 1 µm in diameter and not more than 5% of particles are of
size less then 0.05 µm in diameter. Preferably the aluminosilicate zeolite particles
have an average particle size diameter of between 0.01µm and 1µm, more preferably
between 0.05 µm and 0.9 µm, most preferably between 0.1µm and 0.6 µm.
[0077] Zeolite A has the formula
Na 12 [AlO
2)
12 (SiO
2)
12]. xH
2O
wherein x is from 20 to 30, especially 27. Zeolite X has the formula Na
86 [(AlO
2)
86(SiO
2)
106]. 276 H
2O. Zeolite MAP, as disclosed in EP-B-384,070 is a preferred zeolite builder herein.
[0078] Preferred aluminosilicate zeolites are the colloidal aluminosilicate zeolites. When
employed as a component of a detergent composition colloidal aluminosilicate zeolites,
especially colloidal zeolite A, provide enhanced builder performance in terms of providing
improved stain removal. Enhanced builder performance is also seen in terms of reduced
fabric encrustation and improved fabric whiteness maintenance; problems believed to
be associated with poorly built detergent compositions.
[0079] A surprising finding is that mixed aluminosilicate zeolite detergent compositions
comprising colloidal zeolite A and colloidal zeolite Y provide equal calcium ion sequestration
performance versus an equal weight of commercially available zeolite A. Another surprising
finding is that mixed aluminosilicate zeolite detergent compositions, described above,
provide improved magnesium ion sequestration performance versus an equal weight of
commercially available zeolite A.
Surfactant
[0080] Surfactants are preferred detergent active components of the compositions described
herein. Suitable surfactants are selected from anionic, cationic, nonionic ampholytic
and zwitterionic surfactants and mixtures thereof. Automatic dishwashing machine products
should be low foaming in character and thus the foaming of the surfactant system for
use in dishwashing methods must be suppressed or more preferably be low foaming, typically
nonionic in character. Sudsing caused by surfactant systems used in laundry cleaning
methods need not be suppressed to the same extent as is necessary for dishwashing.
The surfactant is typically present at a level of from 0.2% to 30% by weight, more
preferably from 0.5% to 10% by weight, most preferably from 1% to 5% by weight of
the composition of active detergent components.
[0081] A typical listing of anionic, nonionic, ampholytic and zwitterionic classes, and
species of these surfactants, is given in U.S.P. 3,929,678 issued to Laughlin and
Heuring on December, 30, 1975. A list of suitable cationic surfactants is given in
U.S.P. 4,259,217 issued to Murphy on March 31,1981. A listing of surfactants typically
included in automatic dishwashing detergent compositions is given for example, in
EP-A-0414 549 and PCT Applications No,s WO 93/08876 and WO 93/08874.
Nonionic surfactant
[0082] Essentially any nonionic surfactants useful for detersive purposes can be included
in the detergent tablet. Preferred, non-limiting classes of useful nonionic surfactants
are listed below.
Nonionic ethoxylated alcohol surfactant
[0083] The alkyl ethoxylate condensation products of aliphatic alcohols with from 1 to 25
moles of ethylene oxide are suitable for use herein. The alkyl chain of the aliphatic
alcohol can either be straight or branched, primary or secondary, and generally contains
from 6 to 22 carbon atoms. Particularly preferred are the condensation products of
alcohols having an alkyl group containing from 8 to 20 carbon atoms with from 2 to
10 moles of ethylene oxide per mole of alcohol.
End-capped alkyl alkoxylate surfactant
[0084] A suitable endcapped alkyl alkoxylate surfactant is the epoxy-capped poly(oxyalkylated)
alcohols represented by the formula:
R
1O[CH
2CH(CH
3)O]
x[CH
2CH
2O]
y[CH
2CH(OH)R
2] (I)
wherein R
1 is a linear or branched, aliphatic hydrocarbon radical having from 4 to 18 carbon
atoms; R
2 is a linear or branched aliphatic hydrocarbon radical having from 2 to 26 carbon
atoms; x is an integer having an average value of from 0.5 to 1.5, more preferably
1; and y is an integer having a value of at least 15, more preferably at least 20.
[0085] Preferably, the surfactant of formula I, at least 10 carbon atoms in the terminal
epoxide unit [CH
2CH(OH)R
2]. Suitable surfactants of formula I, according to the present invention, are Olin
Corporation's POLY-TERGENT® SLF-18B nonionic surfactants, as described, for example,
in WO 94/22800, published October 13, 1994 by Olin Corporation.
Ether-capped poly(oxyalkylated) alcohols
[0086] Preferred surfactants for use herein include ether-capped poly(oxyalkylated) alcohols
having the formula:
R
1O[CH
2CH(R
3)O]
x[CH
2]
kCH(OH)[CH
2]
jOR
2
wherein R
1 and R
2 are linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon
radicals having from I to 30 carbon atoms; R
3 is H, or a linear aliphatic hydrocarbon radical having from 1 to 4 carbon atoms;
x is an integer having an average value from 1 to 30, wherein when x is 2 or greater
R
3 may be the same or different and k and j are integers having an average value of
from 1 to 12, and more preferably 1 to 5.
[0087] R
1 and R
2 are preferably linear or branched, saturated or unsaturated, aliphatic or aromatic
hydrocarbon radicals having from 6 to 22 carbon atoms with 8 to 18 carbon atoms being
most preferred. H or a linear aliphatic hydrocarbon radical having from 1 to 2 carbon
atoms is most preferred for R
3. Preferably, x is an integer having an average value of from 1 to 20, more preferably
from 6 to 15.
[0088] As described above, when, in the preferred embodiments, and x is greater than 2,
R3 may be the same or different. That is, R
3 may vary between any of the alklyeneoxy units as described above. For instance, if
x is 3, R
3 may be be selected to form ethlyeneoxy(EO) or propyleneoxy(PO) and may vary in order
of (EO)(PO)(EO), (EO)(EO)(PO); (EO)(EO)(EO); (PO)(EO)(PO); (PO)(PO)(EO) and (PO)(PO)(PO).
Of course, the integer three is chosen for example only and the variation may be much
larger with a higher integer value for x and include, for example, mulitple (EO) units
and a much small number of (PO) units.
[0089] Particularly preferred surfactants as described above include those that have a low
cloud point of less than 20°C. These low cloud point surfactants may then be employed
in conjunction with a high cloud point surfactant as described in detail below for
superior grease cleaning benefits.
[0090] Most preferred ether-capped poly(oxyalkylated) alcohol surfactants are those wherein
k is 1 and j is 1 so that the surfactants have the formula:
R
1 O[CH
2CH(R
3)O]
xCH
2CH(OH)CH
2OR
2
where R
1, R
2 and R
3 are defined as above and x is an integer with an average value of from 1 to 30, preferably
from 1 to 20, and even more preferably from 6 to 18. Most preferred are surfactants
wherein R
1 and R
2 range from 9 to 14, R
3 is H forming ethyleneoxy and x ranges from 6 to 15.
[0091] The ether-capped poly(oxyalkylated) alcohol surfactants comprise three general components,
namely a linear or branched alcohol, an alkylene oxide and an alkyl ether end cap.
The alkyl ether end cap and the alcohol serve as a hydrophobic, oil-soluble portion
of the molecule while the alkylene oxide group forms the hydrophilic, water-soluble
portion of the molecule.
[0092] These surfactants exhibit significant improvements in spotting and filming characteristics
and removal of greasy soils, when used in conjunction with high cloud point surfactants,
relative to conventional surfactants.
[0093] Generally speaking, the ether-capped poly(oxyalkylene) alcohol surfactants of the
present invention may be produced by reacting an aliphatic alcohol with an epoxide
to form an ether which is then reacted with a base to form a second epoxide. The second
epoxide is then reacted with an alkoxylated alcohol to form the novel compounds of
the present invention. Examples of methods of preparing the ether-capped poly(oxyalkylated)
alcohol surfactants are described below:
Preparation of C12/14 alkyl glycidyl ether
[0094] A C
12/14 fatty alcohol (100.00 g, 0.515 mol.) and tin (IV) chloride (0.58 g, 2.23 mmol, available
from Aldrich) are combined in a 500 mL three-necked round-bottomed flask fitted with
a condenser, argon inlet, addition funnel, magnetic stirrer and internal temperature
probe. The mixture is heated to 60 °C. Epichlorhydrin (47.70 g, 0.515 mol, available
from Aldrich) is added dropwise so as to keep the temperature between 60-65 °C. After
stirring an additional hour at 60 °C, the mixture is cooled to room temperature. The
mixture is treated with a 50% solution of sodium hydroxide (61.80 g, 0.773 mol, 50%)
while being stirred mechanically. After addition is completed, the mixture is heated
to 90 °C for 1.5 h, cooled, and filtered with the aid of ethanol. The filtrate is
separated and the organic phase is washed with water (100 mL), dried over MgSO
4, filtered, and concentrated. Distillation of the oil at 100-120 °C (0.1 mm Hg) providing
the glycidyl ether as an oil.
Preparation of C12/14 alkyl-C9/11 ether capped alcohol surfactant
[0095] Neodol® 91-8 (20.60 g, 0.0393 mol ethoxylated alcohol available from the Shell chemical
Co.) and tin (IV) chloride (0.58 g, 2.23 mmol) are combined in a 250 mL three-necked
round-bottomed flask fitted with a condenser, argon inlet, addition funnel, magnetic
stirrer and internal temperature probe. The mixture is heated to 60 °C at which point
C
12/14 alkyl glycidyl ether (11.00 g, 0.0393 mol) is added dropwise over 15 min. After stirring
for 18 h at 60 °C, the mixture is cooled to room temperature and dissolved in an equal
portion of dichloromethane. The solution is passed through a 1 inch pad of silica
gel while eluting with dichloromethane. The filtrate is concentrated by rotary evaporation
and then stripped in a kugelrohr oven (100 °C, 0.5 mm Hg) to yield the surfactant
as an oil.
Nonionic ethoxylated/propoxylated fatty alcohol surfactant
[0096] The ethoxylated C
6-C
18 fatty alcohols and C
6-C
18 mixed ethoxylated/propoxylated fatty alcohols are suitable surfactants for use herein,
particularly where water soluble. Preferably the ethoxylated fatty alcohols are the
C
10-C
18 ethoxylated fatty alcohols with a degree of ethoxylation of from 3 to 50, most preferably
these are the C
12-C
18 ethoxylated fatty alcohols with a degree of ethoxylation from 3 to 40. Preferably
the mixed ethoxylated/propoxylated fatty alcohols have an alkyl chain length of from
10 to 18 carbon atoms, a degree of ethoxylation of from 3 to 30 and a degree of propoxylation
of from 1 to 10.
Nonionic EO/PO condensates with propylene glycol
[0097] The condensation products of ethylene oxide with a hydrophobic base formed by the
condensation of propylene oxide with propylene glycol are suitable for use herein.
The hydrophobic portion of these compounds preferably has a molecular weight of from
1500 to 1800 and exhibits water insolubility. Examples of compounds of this type include
certain of the commercially-available Pluronic™ surfactants, marketed by BASF.
Nonionic EO condensation products with propylene oxide/ethylene diamine adducts
[0098] The condensation products of ethylene oxide with the product resulting from the reaction
of propylene oxide and ethylenediamine are suitable for use herein. The hydrophobic
moiety of these products consists of the reaction product of ethylenediamine and excess
propylene oxide, and generally has a molecular weight of from 2500 to 3000. Examples
of this type of nonionic surfactant include certain of the commercially available
Tetronic™ compounds, marketed by BASF.
Mixed Nonionic Surfactant System
[0099] In a preferred embodiment of the present invention the detergent tablet comprises
a mixed nonionic surfactant system comprising at least one low cloud point nonionic
surfactant and at least one high cloud point nonionic surfactant.
[0100] "Cloud point", as used herein, is a well known property of nonionic surfactants which
is the result of the surfactant becoming less soluble with increasing temperature,
the temperature at which the appearance of a second phase is observable is referred
to as the "cloud point" (See Kirk Othmer's Encyclopedia of Chemical Technology, 3
rd Ed. Vol. 22, pp. 360-379).
[0101] As used herein, a "low cloud point" nonionic surfactant is defined as a nonionic
surfactant system ingredient having a cloud point of less than 30°C, preferably less
than 20°C, and most preferably less than 10°C. Typical low cloud point nonionic surfactants
include nonionic alkoxylated surfactants, especially ethoxylates derived from primary
alcohol, and polyoxypropylene/polyoxyethylene/polyoxypropylene (PO/EO/PO) reverse
block polymers. Also, such low cloud point nonionic surfactants include, for example,
ethoxylated-propoxylated alcohol (e.g., Olin Corporation's Poly-Tergent® SLF18), epoxy-capped
poly(oxyalkylated) alcohols (e.g., Olin Corporation's Poly-Tergent® SLF18B series
of nonionics, as described, for example, in WO 94/22800, published October 13, 1994
by Olin Corporation)and the ether-capped poly(oxyalkylated) alcohol surfactants.
[0102] Nonionic surfactants can optionally contain propylene oxide in an amount up to 15%
by weight. Other preferred nonionic surfactants can be prepared by the processes described
in U.S. Patent 4,223,163, issued September 16, 1980, Builloty, incorporated herein
by reference.
[0103] Low cloud point nonionic surfactants additionally comprise a polyoxyethylene, polyoxypropylene
block polymeric compound. Block polyoxyethylene-polyoxypropylene polymeric compounds
include those based on ethylene glycol, propylene glycol, glycerol, trimethylolpropane
and ethylenediamine as initiator reactive hydrogen compound. Certain of the block
polymer surfactant compounds designated PLURONIC®, REVERSED PLURONIC®, and TETRONIC®
by the BASF-Wyandotte Corp., Wyandotte, Michigan, are suitable in ADD compositions
of the invention. Preferred examples include REVERSED PLURONIC® 25R2 and TETRONIC®
702, Such surfactants are typically useful herein as low cloud point nonionic surfactants.
[0104] As used herein, a "high cloud point" nonionic surfactant is defined as a nonionic
surfactant system ingredient having a cloud point of greater than 40°C, preferably
greater than 50°C, and more preferably greater than 60°C. Preferably the nonionic
surfactant system comprises an ethoxylated surfactant derived from the reaction of
a monohydroxy alcohol or alkylphenol containing from 8 to 20 carbon atoms, with from
6 to 15 moles of ethylene oxide per mole of alcohol or alkyl phenol on an average
basis. Such high cloud point nonionic surfactants include, for example, Tergitol 15S9
(supplied by Union Carbide), Rhodasurf TMD 8.5 (supplied by Rhone Poulenc), and Neodol
91-8 (supplied by Shell).
[0105] It is also preferred for purposes of the present invention that the high cloud point
nonionic surfactant further have a hydrophile-lipophile balance ("HLB"; see Kirk Othmer
hereinbefore) value within the range of from 9 to 15, preferably 11 to 15. Such materials
include, for example, Tergitol 15S9 (supplied by Union Carbide), Rhodasurf TMD 8.5
(supplied by Rhone Poulenc), and Neodol 91-8 (supplied by Shell).
[0106] Another preferred high cloud point nonionic surfactant is derived from a straight
or preferably branched chain or secondary fatty alcohol containing from 6 to 20 carbon
atoms (C
6-C
20 alcohol), including secondary alcohols and branched chain primary alcohols. Preferably,
high cloud point nonionic surfactants are branched or secondary alcohol ethoxylates,
more preferably mixed C9/11 or C11/15 branched alcohol ethoxylates, condensed with
an average of from 6 to 15 moles, preferably from 6 to 12 moles, and most preferably
from 6 to 9 moles of ethylene oxide per mole of alcohol. Preferably the ethoxylated
nonionic surfactant so derived has a narrow ethoxylate distribution relative to the
average.
[0107] In a preferred embodiment the detergent tablet comprising such a mixed surfactant
system also comprises an amount of water-soluble salt to provide conductivity in deionised
water measured at 25°C greater than 3 milli Siemens/cm, preferably greater than 4
milli Siemens/cm, most preferably greater than 4.5 milli Siemens/cm as described in
co-pending GB Patent Application (attorney docket number CM 1573F).
[0108] In another preferred embodiment the mixed surfactant system dissolves in water having
a hardness of 1.246mmol/L in any suitable cold-fill automatic dishwasher to provide
a solution with a surface tension of less than 4 Dynes/cm
2 at less than 45°C, preferably less than 40°C, most preferably less than 35°C as described
in co-pending U.S. Patent Application (attorney docket number 6252).
[0109] In another preferred embodiment the high cloud point and low cloud point surfactants
of the mixed surfactant system are separated such that one of either the high cloud
point or low cloud point surfactants is present in a first matrix and the other is
present in a second matrix as described in co-pending U.S. Patent Application (attorney
docket number 6252). For the purposes of the present invention, the first matrix may
be a first particulate and the second matrix may be a second particulate. A surfactant
may be applied to a particulate by any suitable known method, preferably the surfactant
is sprayed onto the particulate. In a preferred aspect the first matrix is the compressed
portion and the second matrix is the non-compressed portion of the detergent tablet
of the present invention. Preferably the low cloud point surfactant is present in
the compressed portion and the high cloud point surfactant is present in the non-compressed
portion of the detergent tablet of the present invention.
Anionic surfactant
[0110] Essentially any anionic surfactants useful for detersive purposes are suitable. These
can include salts (including, for example, sodium, potassium, ammonium, and substituted
ammonium salts such as mono-, di- and triethanolamine salts) of the anionic sulfate,
sulfonate, carboxylate and sarcosinate surfactants. Anionic sulfate surfactants are
preferred.
[0111] Other anionic surfactants include the isethionates such as the acyl isethionates,
N-acyl taurates, fatty acid amides of methyl tauride, alkyl succinates and sulfosuccinates,
monoesters of sulfosuccinate (especially saturated and unsaturated C
12-C
18 monoesters) diesters of sulfosuccinate (especially saturated and unsaturated C
6-C
14 diesters), N-acyl sarcosinates. Resin acids and hydrogenated resin acids are also
suitable, such as rosin, hydrogenated rosin, and resin acids and hydrogenated resin
acids present in or derived from tallow oil.
Anionic sulfate surfactant
[0112] Anionic sulfate surfactants suitable for use herein include the linear and branched
primary and secondary alkyl sulfates, alkyl ethoxysulfates, fatty oleoyl glycerol
sulfates, alkyl phenol ethylene oxide ether sulfates, the C
5-C
17 acyl-N-(C
1-C
4 alkyl) and -N-(C
1-C
2 hydroxyalkyl) glucamine sulfates, and sulfates of alkylpolysaccharides such as the
sulfates of alkylpolyglucoside (the nonionic nonsulfated compounds being described
herein).
[0113] Alkyl sulfate surfactants are preferably selected from the linear and branched primary
C
10-C
18 alkyl sulfates, more preferably the C
11-C
15 branched chain alkyl sulfates and the C
12-C
14 linear chain alkyl sulfates.
[0114] Alkyl ethoxysulfate surfactants are preferably selected from the group consisting
of the C
10-C
18 alkyl sulfates which have been ethoxylated with from 0.5 to 20 moles of ethylene
oxide per molecule. More preferably, the alkyl ethoxysulfate surfactant is a C
11-C
18, most preferably C
11-C
15 alkyl sulfate which has been ethoxylated with from 0.5 to 7, preferably from 1 to
5, moles of ethylene oxide per molecule.
[0115] A particularly preferred aspect of the invention employs mixtures of the preferred
alkyl sulfate and alkyl ethoxysulfate surfactants. Such mixtures have been disclosed
in PCT Patent Application No. WO 93/18124.
Anionic sulfonate surfactant
[0116] Anionic sulfonate surfactants suitable for use herein include the salts of C
5-C
20 linear alkylbenzene sulfonates, alkyl ester sulfonates, C
6-C
22 primary or secondary alkane sulfonates, C
6-C
24 olefin sulfonates, sulfonated polycarboxylic acids, alkyl glycerol sulfonates, fatty
acyl glycerol sulfonates, fatty oleyl glycerol sulfonates, and any mixtures thereof.
Anionic carboxylate surfactant
[0117] Suitable anionic carboxylate surfactants include the alkyl ethoxy carboxylates, the
alkyl polyethoxy polycarboxylate surfactants and the soaps ('alkyl carboxyls'), especially
certain secondary soaps as described herein.
[0118] Suitable alkyl ethoxy carboxylates include those with the formula RO(CH
2CH
2O)
x CH
2C00
-M
+ wherein R is a C
6 to C
18 alkyl group, x ranges from O to 10, and the ethoxylate distribution is such that,
on a weight basis, the amount of material where x is 0 is less than 20 % and M is
a cation. Suitable alkyl polyethoxy polycarboxylate surfactants include those having
the formula RO-(CHR
1-CHR
2-O)-R
3 wherein R is a C
6 to C
18 alkyl group, x is from 1 to 25, R
1 and R
2 are selected from the group consisting of hydrogen, methyl acid radical, succinic
acid radical, hydroxysuccinic acid radical, and mixtures thereof, and R
3 is selected from the group consisting of hydrogen, substituted or unsubstituted hydrocarbon
having between 1 and 8 carbon atoms, and mixtures thereof.
[0119] Suitable soap surfactants include the secondary soap surfactants which contain a
carboxyl unit connected to a secondary carbon. Preferred secondary soap surfactants
for use herein are water-soluble members selected from the group consisting of the
water-soluble salts of 2-methyl-1-undecanoic acid, 2-ethyl-1-decanoic acid, 2-propyl-1-nonanoic
acid, 2-butyl-1-octanoic acid and 2-pentyl-1-heptanoic acid. Certain soaps may also
be included as suds suppressors.
Alkali metal sarcosinate surfactant
[0120] Other suitable anionic surfactants are the alkali metal sarcosinates of formula R-CON
(R
1) CH
2 COOM, wherein R is a C
5-C
17 linear or branched alkyl or alkenyl group, R
1 is a C
1-C
4 alkyl group and M is an alkali metal ion. Preferred examples are the myristyl and
oleoyl methyl sarcosinates in the form of their sodium salts.
Amphoteric surfactant
[0121] Suitable amphoteric surfactants for use herein include the amine oxide surfactants
and the alkyl amphocarboxylic acids.
[0122] Suitable amine oxides include those compounds having the formula R
3(OR
4)
xN
0(R
5)
2 wherein R
3 is selected from an alkyl, hydroxyalkyl, acylamidopropoyl and alkyl phenyl group,
or mixtures thereof, containing from 8 to 26 carbon atoms; R
4 is an alkylene or hydroxyalkylene group containing from 2 to 3 carbon atoms, or mixtures
thereof; x is from 0 to 5, preferably from 0 to 3; and each R
5 is an alkyl or hydroxyalkyl group containing from I to 3, or a polyethylene oxide
group containing from 1 to 3 ethylene oxide groups. Preferred are C
10-C
18 alkyl dimethylamine oxide, and C
10-18 acylamido alkyl dimethylamine oxide.
[0123] A suitable example of an alkyl aphodicarboxylic acid is Miranol(TM) C2M Conc. manufactured
by Miranol, Inc., Dayton, NJ.
Zwitterionic surfactant
[0124] Zwitterionic surfactants can also be incorporated into the detergent compositions
hereof. These surfactants can be broadly described as derivatives of secondary and
tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives
of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. Betaine
and sultaine surfactants are exemplary zwitterionic surfactants for use herein.
[0125] Suitable betaines are those compounds having the formula R(R')
2N
+R
2COO-
wherein R is a C
6-C
18 hydrocarbyl group, each R
1 is typically C
1-C
3 alkyl, and R
2 is a C
1-C
5 hydrocarbyl group. Preferred betaines are C
12-18 dimethyl-ammonio hexanoate and the C
10-18 acylamidopropane (or ethane) dimethyl (or diethyl) betaines. Complex betaine surfactants
are also suitable for use herein.
Cationic surfactants
[0126] Cationic ester surfactants used in this invention are preferably water dispersible
compound having surfactant properties comprising at least one ester (i.e. -COO-) linkage
and at least one cationically charged group. Other suitable canonic ester surfactants,
including choline ester surfactants, have for example been disclosed in US Patents
No.s 4228042, 4239660 and 4260529.
[0127] Suitable cationic surfactants include the quaternary ammonium surfactants selected
from mono C
6-C
16, preferably C
6-C
10 N-alkyl or alkenyl ammonium surfactants wherein the remaining N positions are substituted
by methyl, hydroxyethyl or hydroxypropyl groups.
Enzymes
[0128] In an embodiment of the present invention an enzyme is an essential feature of the
detergent tablet. In other embodiments of the present invention an enzyme is an optional
detergent active component. Where present said enzymes are selected from the group
consisting of cellulases, hemicellulases, peroxidases, proteases, gluco-amylases,
amylases, xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases,
reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tannases,
pentosanases, malanases, β-glucanases, arabinosidases, hyaluronidase, chondroitinase,
laccase or mixtures thereof.
[0129] Preferred enzymes include protease, amylase, lipase, peroxidases, cutinase and/or
cellulase in conjunction with one or more plant cell wall degrading enzymes.
[0130] The cellulases usable in the present invention include both bacterial or fungal cellulase.
Preferably, they will have a pH optimum of between 5 and 12 and an activity above
50 CEVU (Cellulose Viscosity Unit). Suitable cellulases are disclosed in U.S. Patent
4,435,307, Barbesgoard et al, J61078384 and WO96/02653 which disclose fungal cellulases
produced respectively from Humicola insolens, Trichoderma, Thielavia and Sporotrichum.
EP 739 982 describes cellulases isolated from novel Bacillus species. Suitable cellulases
are also disclosed in GB-A-2.075.028; GB-A-2.095.275; DE-OS-2.247.832 and WO95/26398.
[0131] Examples of such cellulases are cellulases produced by a strain of Humicola insolens
(Humicola grisea var. thermoidea), particularly the Humicola strain DSM 1800. Other
suitable cellulases are cellulases originated from Humicola insolens having a molecular
weight of 50KDa, an isoelectric point of 5.5 and containing 415 amino acids; and a
43kD endoglucanase derived from Humicola insolens, DSM 1800, exhibiting cellulase
activity; a preferred endoglucanase component has the amino acid sequence disclosed
in PCT Patent Application No. WO 91/17243. Also suitable cellulases are the EGIII
cellulases from Trichoderma longibrachiatum described in WO94/21801, Genencor, published
September 29, 1994. Especially suitable cellulases are the cellulases having color
care benefits. Examples of such cellulases are cellulases described in European patent
application No. 91202879.2, filed November 6, 1991 (Novo). Carezyme and Celluzyme
(Novo Nordisk A/S) are especially useful. See also WO91/17244 and WO91/21801. Other
suitable cellulases for fabric care and/or cleaning properties are described in WO96/34092,
WO96/17994 and WO95/24471.
[0132] Said cellulases are normally incorporated in the detergent composition at levels
from 0.0001% to 2% of active enzyme by weight of the detergent composition.
[0133] Peroxidase enzymes are used in combination with oxygen sources, e.g. percarbonate,
perborate, persulfate, hydrogen peroxide, etc. They are used for "solution bleaching",
i.e. to prevent transfer of dyes or pigments removed from substrates during wash operations
to other substrates in the wash solution. Peroxidase enzymes are known in the art,
and include, for example, horseradish peroxidase, ligninase and haloperoxidase such
as chloro- and bromo-peroxidase. Peroxidase-containing detergent compositions are
disclosed, for example, in PCT International Application WO 89/099813, WO89/09813
and in European Patent application EP No. 91202882.6, filed on November 6, 1991 and
EP No. 96870013.8, filed February 20, 1996. Also suitable is the laccase enzyme.
[0134] Preferred enhancers are substitued phenthiazine and phenoxasine 10-Phenothiazinepropionicacid
(PPT), 10-ethylphenothiazine-4-carboxylic acid (EPC), 10-phenoxazinepropionic acid
(POP) and 10-methylphenoxazine (described in WO 94/12621) and substitued syringates
(C3-C5 substitued alkyl syringates) and phenols. Sodium percarbonate or perborate
are preferred sources of hydrogen peroxide.
[0135] Said cellulases and/or peroxidases are normally incorporated in the detergent composition
at levels from 0.0001% to 2% of active enzyme by weight of the detergent composition.
[0136] Other preferred enzymes that can be included in the detergent compositions of the
present invention include lipases. Suitable lipase enzymes for detergent usage include
those produced by microorganisms of the Pseudomonas group, such as Pseudomonas stutzeri
ATCC 19.154, as disclosed in British Patent 1,372,034. Suitable lipases include those
which show a positive immunological cross-reaction with the antibody of the lipase,
produced by the microorganism
Pseudomonas fluorescent IAM 1057. This lipase is available from Amano Pharmaceutical Co. Ltd., Nagoya, Japan,
under the trade name Lipase P "Amano," hereinafter referred to as "Amano-P". Other
suitable commercial lipases include Amano-CES, lipases ex
Chromobacter viscosum, e.g.
Chromobacter viscosum var. lipolyticum NRRLB 3673 from Toyo Jozo Co., Tagata, Japan;
Chromobacter viscosum lipases from U.S. Biochemical Corp., U.S.A. and Disoynth Co., The Netherlands, and
lipases ex
Pseudomonas gladioli. Especially suitable lipases are lipases such as Ml Lipase
R and Lipomax
R (Gist-Brocades) and Lipolase
R and Lipolase Ultra
R(Novo) which have found to be very effective when used in combination with the compositions
of the present invention. Also suitables are the lipolytic enzymes described in EP
258 068, WO 92/05249 and WO 95/22615 by Novo Nordisk and in WO 94/03578, WO 95/35381
and WO 96/00292 by Unilever.
[0137] Also suitable are cutinases [EC 3.1.1.50] which can be considered as a special kind
of lipase, namely lipases which do not require interfacial activation. Addition of
cutinases to detergent compositions have been described in e.g. WO-A-88/09367 (Genencor);
WO 90/09446 (Plant Genetic System) and WO 94/14963 and WO 94/14964 (Unilever).
[0138] The lipases and/or cutinases are normally incorporated in the detergent composition
at levels from 0.0001% to 2% of active enzyme by weight of the detergent composition.
[0139] Suitable proteases are the subtilisins which are obtained from particular strains
of B.
subtilis and
B. licheniformis (subtilisin BPN and BPN'). One suitable protease is obtained from a strain of
Bacillus, having maximum activity throughout the pH range of 8-12, developed and sold as ESPERASE®
by Novo Industries A/S of Denmark, hereinafter "Novo". The preparation of this enzyme
and analogous enzymes is described in GB 1,243,784 to Novo. Other suitable proteases
include ALCALASE®, DURAZYM® and SAVINASE® from Novo and MAXATASE®, MAXACAL®, PROPERASE®
and MAXAPEM® (protein engineered Maxacal) from Gist-Brocades. Proteolytic enzymes
also encompass modified bacterial serine proteases, such as those described in European
Patent Application Serial Number 87 303761.8, filed April 28, 1987 (particularly pages
17, 24 and 98), and which is called herein "Protease B", and in European Patent Application
199,404, Venegas, published October 29, 1986, which refers to a modified bacterial
serine protealytic enzyme which is called "Protease A" herein. Suitable is what is
called herein "Protease C", which is a variant of an alkaline serine protease from
Bacillus in which lysine replaced arginine at position 27, tyrosine replaced valine at position
104, serine replaced asparagine at position 123, and alanine replaced threonine at
position 274. Protease C is described in EP 90915958:4, corresponding to WO 91/06637,
Published May 16, 1991. Genetically modified variants, particularly of Protease C,
are also included herein.
[0140] A preferred protease referred to as "Protease D" is a carbonyl hydrolase variant
having an amino acid sequence not found in nature, which is derived from a precursor
carbonyl hydrolase by substituting a different amino acid for a plurality of amino
acid residues at a position in said carbonyl hydrolase equivalent to position +76,
preferably also in combination with one or more amino acid residue positions equivalent
to those selected from the group consisting of +99, +101, +103, +104, +107, +123,
+27, +105, +109, +126, +128, +135, +156, +166, +195, +197, +204, +206, +210, +216,
+217, +218, +222, +260, +265, and/or +274 according to the numbering of
Bacillus amyloliquefaciens subtilisin, as described in WO95/10591 and in the patent application of C. Ghosh,
et al, "Bleaching Compositions Comprising Protease Enzymes" having US Serial No. 08/322,677,
filed October 13, 1994.
[0141] Also suitable for the present invention are proteases described in patent applications
EP 251 446 and WO 91/06637, protease BLAP® described in WO91/02792 and their variants
described in WO 95/23221.
[0142] See also a high pH protease from Bacillus sp. NCIMB 40338 described in WO 93/18140
A to Novo. Enzymatic detergents comprising protease, one or more other enzymes, and
a reversible protease inhibitor are described in WO 92/03529 A to Novo. When desired,
a protease having decreased adsorption and increased hydrolysis is available as described
in WO 95/07791 to Procter & Gamble. A recombinant trypsin-like protease for detergents
suitable herein is described in WO 94/25583 to Novo. Other suitable proteases are
described in EP 516 200 by Unilever.
[0143] Other preferred protease enzymes include protease enzymes which are a carbonyl hydrolase
variant having an amino acid sequence not found in nature, which is derived by replacement
of a plurality of amino acid residues of a precursor carbonyl hydrolase with different
amino acids, wherein said plurality of amino acid residues replaced in the precursor
enzyme correspond to position +210 in combination with one or more of the following
residues: +33, +62, +67, +76, +100, +101, +103, +104, +107, +128, +129, +130, +132,
+135, +156, +158, +164, +166, +167, +170, +209, +215, +217, +218 and +222, where the
numbered positions correspond to naturally-occurring subtilisin from
Bacillus amyloliquefaciens or to equivalent amino acid residues in other carbonyl hydrolases or subtilisins
(such as
Bacillus lentus subtilisin). Preferred enzymes of this type include those having position changes
+210, +76, +103, +104, +156, and +166.
[0144] The proteolytic enzymes are incorporated in the detergent compositions of the present
invention a level of from 0.0001% to 2%, preferably from 0.001% to 0.2%, more preferably
from 0.005% to 0.1% pure enzyme by weight of the composition.
[0145] Amylases (α and/or β) can be included for removal of carbohydrate-based stains. WO94/02597,
Novo Nordisk A/S published February 03, 1994, describes cleaning compositions which
incorporate mutant amylases. See also WO95/10603, Novo Nordisk A/S, published April
20, 1995. Other amylases known for use in cleaning compositions include both α- and
β-arnylases. α-Amylases are known in the art and include those disclosed in US Pat.
no. 5,003,257; EP 252,666; WO/91/00353; FR 2,676,456; EP 285,123; EP 525,610; EP 368,341;
and British Patent specification no. 1,296,839 (Novo). Other suitable amylases are
stability-enhanced amylases described in WO94/18314, published August 18, 1994 and
WO96/05295, Genencor, published February 22, 1996 and amylase variants having additional
modification in the immediate parent available from Novo Nordisk A/S, disclosed in
WO 95/10603, published April 95. Also suitable are amylases described in EP 277 216,
WO95/26397 and WO96/23873 (all by Novo Nordisk).
[0146] Examples of commercial α-amylases products are Purafect Ox Am® from Genencor and
Termamyl® , Ban® ,Fungamyl® and Duramyl® , all available from Novo Nordisk A/S Denmark.
WO95/26397 describes other suitable amylases : α-amylases characterised by having
a specific activity at least 25% higher than the specific activity of Termamyl® at
a temperature range of 25°C to 55°C and at a pH value in the range of 8 to 10, measured
by the Phadebas® α-amylase activity assay. Suitable are variants of the above enzymes,
described in WO96/23873 (Novo Nordisk). Other amylolytic enzymes with improved properties
with respect to the activity level and the combination of thermostability and a higher
activity level are described in WO95/35382.
[0147] Preferred amylase enzymes include those described in WO95/26397 and in co-pending
application by Novo Nordisk PCTIDK96/00056.
[0148] The amylolytic enzymes are incorporated in the detergent compositions of the present
invention a level of from 0.0001% to 2%, preferably from 0.00018% to 0.06%, more preferably
from 0.00024% to 0.048% pure enzyme by weight of the composition
[0149] In a particularly preferred embodiment, detergent tablets of the present invention
comprise amylase enzymes, particularly those described in WO95/26397 and co-pending
application by Novo Nordisk PCT/DK96/00056 in combination with a complementary amylase.
[0150] By "complementary" it is meant the addition of one or more amylase suitable for detergency
purposes. Examples of complementary amylases (α and/or β) are described below. WO94/02597
and WO95/10603, Novo Nordisk A/S describe cleaning compositions which incorporate
mutant amylases. Other amylases known for use in cleaning compositions include both
α- and β-amylases. α-Amylases are known in the art and include those disclosed in
US Pat. no. 5,003,257; EP 252,666; WO/91/00353; FR 2,676,456; EP 285,123; EP 525,610;
EP 368,341; and British Patent specification no. 1,296,839 (Novo). Other suitable
amylases are stability-enhanced amylases described in WO94/18314, and WO96/05295,
Genencor and amylase variants having additional modification in the immediate parent
available from Novo Nordisk A/S, disclosed in WO 95/10603. Also suitable are amylases
described in EP 277 216 (Novo Nordisk). Examples of commercial α-amylases products
are Purafect Ox Am® from Genencor and Termamyl® , Ban® ,Fungamyl® and Duramyl® , all
available from Novo Nordisk A/S Denmark. WO95/26397 describes other suitable amylases
: α-amylases characterised by having a specific activity at least 25% higher than
the specific activity of Termamyl® at a temperature range of 25°C to 55°C and at a
pH value in the range of 8 to 10, measured by the Phadebas® α-amylase activity assay.
Suitable are variants of the above enzymes, described in WO96/23873 (Novo Nordisk).
Other amylolytic enzymes with improved properties with respect to the activity level
and the combination of thermostability and a higher activity level are described in
WO95/35382. Preferred complementary amylases for the present invention are the amylases
sold under the tradename Purafect Ox Am
R described in WO 94/18314, WO96/05295 sold by Genencor; Termamyl® , Fungamyl® , Ban®
and Duramyl® , all available from Novo Nordisk A/S and Maxamyl® by Gist-Brocades.
[0151] Said complementary amylase is generally incorporated in the detergent compositions
of the present invention a level of from 0.0001% to 2%, preferably from 0.00018% to
0.06%, more preferably from 0.00024% to 0.048% pure enzyme by weight of the composition.
Preferably a weight of pure enzyme ratio of specific amylase to the complementary
amylase is comprised between 9:1 to 1:9, more preferably between 4:1 to 1:4, and most
preferably between 2:1 and 1:2.
[0152] The above-mentioned enzymes may be of any suitable origin, such as vegetable, animal,
bacterial, fungal and yeast origin. Origin can further be mesophilic or extremophilic
(psychrophilic, psychrotrophic, thermophilic, barophilic, alkalophilic, acidophilic,
halophilic, etc.). Purified or non-purified forms of these enzymes may be used. Also
included by definition, are mutants of native enzymes. Mutants can be obtained e.g.
by protein and/or genetic engineering, chemical and/or physical modifications of native
enzymes. Common practice as well is the expression of the enzyme via host organisms
in which the genetic material responsible for the production of the enzyme has been
cloned.
[0153] Said enzymes are normally incorporated in the detergent composition at levels from
0.0001% to 2% of active enzyme by weight of the detergent composition. The enzymes
can be added as separate single ingredients (prills, granulates, stabilized liquids,
etc... containing one enzyme) or as mixtures of two or more enzymes (e.g. cogranulates).
[0154] Other suitable detergent ingredients that can be added are enzyme oxidation scavengers
which are described in Copending European Patent application 92870018.6 filed on January
31, 1992. Examples of such enzyme oxidation scavengers are ethoxylated tetraethylene
polyamines.
[0155] A range of enzyme materials and means for their incorporation into synthetic detergent
compositions is also disclosed in WO 9307263 A and WO 9307260 A to Genencor International,
WO 8908694 A to Novo, and U.S. 3,553,139, January 5, 1971 to McCarty et al. Enzymes
are further disclosed in U.S. 4,101,457, Place et al, July 18, 1978, and in U.S. 4,507,219,
Hughes, March 26, 1985. Enzyme materials useful for liquid detergent formulations,
and their incorporation into such formulations, are disclosed in U.S. 4,261,868, Hora
et al, April 14, 1981. Enzymes for use in detergents can be stabilised by various
techniques. Enzyme stabilisation techniques are disclosed and exemplified in U.S.
3,600,319, August 17, 1971, Gedge et al, EP 199,405 and EP 200,586, October 29, 1986,
Venegas. Enzyme stabilisation systems are also described, for example, in U.S. 3,519,570.
A useful Bacillus, sp. AC13 giving proteases, xylanases and cellulases, is described
in WO 9401532 A to Novo.
Bleaching agent
[0156] A highly preferred component of the composition of active detergent components is
a bleaching agent. Suitable bleaching agents include chlorine and oxygen-releasing
bleaching agents.
[0157] In one preferred aspect the oxygen-releasing bleaching agent contains a hydrogen
peroxide source and an organic peroxyacid bleach precursor compound. The production
of the organic peroxyacid occurs by an in situ reaction of the precursor with a source
of hydrogen peroxide. Preferred sources of hydrogen peroxide include inorganic perhydrate
bleaches. In an alternative preferred aspect a preformed organic peroxyacid is incorporated
directly into the composition. Compositions containing mixtures of a hydrogen peroxide
source and organic peroxyacid precursor in combination with a preformed organic peroxyacid
are also envisaged.
Inorganic perhydrate bleaches
[0158] The compositions of active detergent components preferably include a hydrogen peroxide
source, as an oxygen-releasing bleach. Suitable hydrogen peroxide sources include
the inorganic perhydrate salts.
[0159] The inorganic perhydrate salts are normally incorporated in the form of the sodium
salt at a level of from 1% to 40% by weight, more preferably from 2% to 30% by weight
and most preferably from 5% to 25% by weight of the compositions.
[0160] Examples of inorganic perhydrate salts include perborate, percarbonate, perphosphate,
persulfate and persilicate salts. The inorganic perhydrate salts are normally the
alkali metal salts. The inorganic perhydrate salt may be included as the crystalline
solid without additional protection. For certain perhydrate salts however, the preferred
executions of such granular compositions utilize a coated form of the material which
provides better storage stability for the perhydrate salt in the granular product.
[0161] Sodium perborate can be in the form of the monohydrate of nominal formula NaBO
2H
2O
2 or the tetrahydrate NaBO
2H
2O
2.3H
2O.
[0162] Alkali metal percarbonates, particularly sodium percarbonate are preferred perhydrates
for inclusion in compositions in accordance with the invention. Sodium percarbonate
is an addition compound having a formula corresponding to 2Na
2CO
3.3H
2O
2, and is available commercially as a crystalline solid. Sodium percarbonate, being
a hydrogen peroxide addition compound tends on dissolution to release the hydrogen
peroxide quite rapidly which can increase the tendency for localised high bleach concentrations
to arise. The percarbonate is most preferably incorporated into such compositions
in a coated form which provides in-product stability.
[0163] A suitable coating material providing in product stability comprises mixed salt of
a water soluble alkali metal sulphate and carbonate. Such coatings together with coating
processes have previously been described in GB-1,466,799, granted to Interox on 9th
March 1977. The weight ratio of the mixed salt coating material to percarbonate lies
in the range from 1 : 200 to 1 : 4, more preferably from 1 : 99 to 1 : 9, and most
preferably from 1 : 49 to 1 :19. Preferably, the mixed salt is of sodium sulphate
and sodium carbonate which has the general formula Na
2SO
4.n.Na
2CO
3 wherein n is from 0.1 to 3, preferably n is from 0.3 to 1.0 and most preferably n
is from 0.2 to 0.5.
[0164] Another suitable coating material providing in product stability, comprises sodium
silicate of SiO
2 : Na
2O ratio from 1.8 : 1 to 3.0 : 1, preferably 1.8:1 to 2.4:1, and/or sodium metasilicate,
preferably applied at a level of from 2% to 10%, (normally from 3% to 5%) of SiO
2 by weight of the inorganic perhydrate salt. Magnesium silicate can also be included
in the coating. Coatings that contain silicate and borate salts or boric acids or
other inorganics are also suitable.
[0165] Other coatings which contain waxes, oils, fatty soaps can also be used advantageously
within the present invention.
[0166] Potassium peroxymonopersulfate is another inorganic perhydrate salt of utility in
the compositions herein.
Peroxyacid bleach precursor
[0167] Peroxyacid bleach precursors are compounds which react with hydrogen peroxide in
a perhydrolysis reaction to produce a peroxyacid. Generally peroxyacid bleach precursors
may be represented as

where L is a leaving group and X is essentially any functionality, such that on perhydrolysis
the structure of the peroxyacid produced is

[0168] Peroxyacid bleach precursor compounds are preferably incorporated at a level of from
0.5% to 20% by weight, more preferably from 1% to 10% by weight, most preferably from
1.5% to 5% by weight of the compositions.
[0169] Suitable peroxyacid bleach precursor compounds typically contain one or more Nor
O-acyl groups, which precursors can be selected from a wide range of classes. Suitable
classes include anhydrides, esters, imides, lactams and acylated derivatives of imidazoles
and oximes. Examples of useful materials within these classes are disclosed in GB-A-1586789.
Suitable esters are disclosed in GB-A-836988, 864798, 1147871, 2143231 and EP-A-0170386.
Leaying groups
[0170] The leaving group, hereinafter L group, must be sufficiently reactive for the perhydrolysis
reaction to occur within the optimum time frame (e.g., a wash cycle). However, if
L is too reactive, this activator will be difficult to stabilise for use in a bleaching
composition.
Preferred L groups are selected from the group consisting of:
[0171]

and mixtures thereof, wherein R
1 is an alkyl, aryl, or alkaryl group containing from 1 to 14 carbon atoms, R
3 is an alkyl chain containing from 1 to 8 carbon atoms, R
4 is H or R
3, R
5 is an alkenyl chain containing from 1 to 8 carbon atoms and Y is H or a solubilizing
group. Any of R
1, R
3 and R
4 may be substituted by essentially any functional group including, for example alkyl,
hydroxy, alkoxy, halogen, amine, nitrosyl, amide and ammonium or alkyl ammonium groups.
[0172] The preferred solubilizing groups are -SO
3-M
+, -CO
2-M
+, -SO
4-M
+, -N
+(R
3)
4X
- and O<--N(R
3)
3 and most preferably -SO
3-M
+ and -CO
2-M
+ wherein R
3 is an alkyl chain containing from 1 to 4 carbon atoms, M is a cation which provides
solubility to the bleach activator and X is an anion which provides solubility to
the bleach activator. Preferably, M is an alkali metal, ammonium or substituted ammonium
cation, with sodium and potassium being most preferred, and X is a halide, hydroxide,
methylsulfate or acetate anion.
Perbenzoic acid precursor
[0173] Perbenzoic acid precursor compounds provide perbenzoic acid on perhydrolysis.
[0174] Suitable O-acylated perbenzoic acid precursor compounds include the substituted and
unsubstituted benzoyl oxybenzene sulfonates, including for example benzoyl oxybenzene
sulfonate:

[0175] Also suitable are the benzoylation products of sorbitol, glucose, and all saccharides
with benzoylating agents, including for example:

[0176] Perbenzoic acid precursor compounds of the imide type include N-benzoyl succinimide,
tetrabenzoyl ethylene diamine and the N-benzoyl substituted ureas. Suitable imidazole
type perbenzoic acid precursors include N-benzoyl imidazole and N-benzoyl benzimidazole
and other useful N-acyl group-containing perbenzoic acid precursors include N-benzoyl
pyrrolidone, dibenzoyl taurine and benzoyl pyroglutamic acid.
[0177] Other perbenzoic acid precursors include the benzoyl diacyl peroxides, the benzoyl
tetraacyl peroxides, and the compound having the formula:

[0178] Phthalic anhydride is another suitable perbenzoic acid precursor compound herein:

[0179] Suitable N-acylated lactam perbenzoic acid precursors have the formula:

wherein n is from 0 to 8, preferably from 0 to 2, and R
6 is a benzoyl group.
Perbenzoic acid derivative precursors
[0180] Perbenzoic acid derivative precursors provide substituted perbenzoic acids on perhydrolysis.
[0181] Suitable substituted perbenzoic acid derivative precursors include any of the herein
disclosed perbenzoic precursors in which the benzoyl group is substituted by essentially
any non-positively charged (i.e.; non-cationic) functional group including, for example
alkyl, hydroxy, alkoxy, halogen, amine, nitrosyl and amide groups.
[0182] A preferred class of substituted perbenzoic acid precursor compounds are the amide
substituted compounds of the following general formulae:

wherein R
1 is an aryl or alkaryl group with from 1 to 14 carbon atoms, R
2 is an arylene, or alkarylene group containing from 1 to 14 carbon atoms, and R
5 is H or an alkyl, aryl, or alkaryl group containing 1 to 10 carbon atoms and L can
be essentially any leaving group. R
1 preferably contains from 6 to 12 carbon atoms. R
2 preferably contains from 4 to 8 carbon atoms. R
1 may be aryl, substituted aryl or alkylaryl containing branching, substitution, or
both and may be sourced from either synthetic sources or natural sources including
for example, tallow fat. Analogous structural variations are permissible for R
2. The substitution can include alkyl, aryl, halogen, nitrogen, sulphur and other typical
substituent groups or organic compounds. R
5 is preferably H or methyl. R
1 and R
5 should not contain more than 18 carbon atoms in total. Amide substituted bleach activator
compounds of this type are described in EP-A-0170386.
Cationic peroxyacid precursors
[0183] Cationic peroxyacid precursor compounds produce cationic peroxyacids on perhydrolysis.
[0184] Typically, cationic peroxyacid precursors are formed by substituting the peroxyacid
part of a suitable peroxyacid precursor compound with a positively charged functional
group, such as an ammonium or alkyl ammonium group, preferably an ethyl or methyl
ammonium group. Cationic peroxyacid precursors are typically present in the compositions
as a salt with a suitable anion, such as for example a halide ion or a methylsulfate
ion.
[0185] The peroxyacid precursor compound to be so cationically substituted may be a perbenzoic
acid, or substituted derivative thereof, precursor compound as described hereinbefore.
Alternatively, the peroxyacid precursor compound may be an alkyl percarboxylic acid
precursor compound or an amide substituted alkyl peroxyacid precursor as described
hereinafter
[0186] Cationic peroxyacid precursors are described in U.S. Patents 4,904,406; 4,751,015;
4,988,451; 4,397,757; 5,269,962; 5,127,852; 5,093,022; 5,106,528; U.K. 1,382,594;
EP 475,512, 458,396 and 284,292; and in JP 87-318,332.
[0187] Suitable cationic peroxyacid precursors include any of the ammonium or alkyl ammonium
substituted alkyl or benzoyl oxybenzene sulfonates, N-acylated caprolactams, and monobenzoyltetraacetyl
glucose benzoyl peroxides.
[0188] A preferred cationically substituted benzoyl oxybenzene sulfonate is the 4-(trimethyl
ammonium) methyl derivative of benzoyl oxybenzene sulfonate:

[0189] A preferred cationically substituted alkyl oxybenzene sulfonate has the formula:

[0190] Preferred cationic peroxyacid precursors of the N-acylated caprolactam class include
the trialkyl ammonium methylene benzoyl caprolactams, particularly trimethyl ammonium
methylene benzoyl caprolactam:

[0191] Other preferred cationic peroxyacid precursors of the N-acylated caprolactam class
include the trialkyl ammonium methylene alkyl caprolactams:

where n is from 0 to 12, particularly from 1 to 5.
[0192] Another preferred cationic peroxyacid precursor is 2-(N,N,N-trimethyl ammonium) ethyl
sodium 4-sulphophenyl carbonate chloride.
Alkyl percarboxylic acid bleach precursors
[0193] Alkyl percarboxylic acid bleach precursors form percarboxylic acids on perhydrolysis.
Preferred precursors of this type provide peracetic acid on perhydrolysis.
[0194] Preferred alkyl percarboxylic precursor compounds of the imide type include the N-,N,N
1N
1 tetra acetylated alkylene diamines wherein the alkylene group contains from 1 to
6 carbon atoms, particularly those compounds in which the alkylene group contains
1, 2 and 6 carbon atoms. Tetraacetyl ethylene diamine (TAED) is particularly preferred.
[0195] Other preferred alkyl percarboxylic acid precursors include sodium 3,5,5-tri-methyl
hexanoyloxybenzene sulfonate (iso-NOBS), sodium nonanoyloxybenzene sulfonate (NOBS),
sodium acetoxybenzene sulfonate (ABS) and penta acetyl glucose.
Amide substituted alkyl peroxyacid precursors
[0196] Amide substituted alkyl peroxyacid precursor compounds are also suitable, including
those of the following general formulae:

wherein R
1 is an alkyl group with from 1 to 14 carbon atoms, R
2 is an alkylene group containing from 1 to 14 carbon atoms, and R
5 is H or an alkyl group containing 1 to 10 carbon atoms and L can be essentially any
leaving group. R
1 preferably contains from 6 to 12 carbon atoms. R
2 preferably contains from 4 to 8 carbon atoms. R
1 may be straight chain or branched alkyl containing branching, substitution, or both
and may be sourced from either synthetic sources or natural sources including for
example, tallow fat. Analogous structural variations are permissible for R
2. The substitution can include alkyl, halogen, nitrogen, sulphur and other typical
substituent groups or organic compounds. R
5 is preferably H or methyl. R
1 and R
5 should not contain more than 18 carbon atoms in total. Amide substituted bleach activator
compounds of this type are described in EP-A-0170386.
Benzoxazin organic peroxyacid precursors
[0197] Also suitable are precursor compounds of the benzoxazin-type, as disclosed for example
in EP-A-332,294 and EP-A-482,807, particularly those having the formula:

including the substituted benzoxazins of the type

wherein R
1 is H, alkyl, alkaryl, aryl, arylalkyl, and wherein R
2, R
3, R
4, and R
5 may be the same or different substituents selected from H, halogen, alkyl, alkenyl,
aryl, hydroxyl, alkoxyl, amino, alkyl amino, COOR
6 (wherein R
6 is H or an alkyl group) and carbonyl functions.
[0198] An especially preferred precursor of the benzoxazin-type is:

Preformed organic peroxyacid
[0199] The organic peroxyacid bleaching system may contain, in addition to, or as an alternative
to, an organic peroxyacid bleach precursor compound, a preformed organic peroxyacid
, typically at a level of from 0.5% to 25% by weight, more preferably from 1% to 10%
by weight of the composition.
[0200] A preferred class of organic peroxyacid compounds are the amide substituted compounds
of the following general formulae:

or

wherein R
1 is an alkyl, aryl or alkaryl group with from 1 to 14 carbon atoms, R
2 is an alkylene, arylene, and alkarylene group containing from 1 to 14 carbon atoms,
and R
5 is H or an alkyl, aryl, or alkaryl group containing I to 10 carbon atoms. R
1 preferably contains from 6 to 12 carbon atoms. R
2 preferably contains from 4 to 8 carbon atoms. R
1 may be straight chain or branched alkyl, substituted aryl or alkylaryl containing
branching, substitution, or both and may be sourced from either synthetic sources
or natural sources including for example, tallow fat. Analogous structural variations
are permissible for R
2. The substitution can include alkyl, aryl, halogen, nitrogen, sulphur and other typical
substituent groups or organic compounds. R
5 is preferably H or methyl. R
1 and R
5 should not contain more than 18 carbon atoms in total. Amide substituted organic
peroxyacid compounds of this type are described in EP-A-0170386.
[0201] Other organic peroxyacids include diacyl and tetraacylperoxides, especially diperoxydodecanedioc
acid, diperoxytetradecanedioc acid, and diperoxyhexadecanedioc acid. Dibenzoyl peroxide
is a preferred organic peroxyacid herein. Mono- and diperazelaic acid, mono- and diperbrassylic
acid, and N-phthaloylaminoperoxicaproic acid are also suitable herein.
Controlled rate of release - means
[0202] A means may be provided for controlling the rate of release of bleaching agent, particularly
oxygen bleach to the wash solution.
[0203] Means for controlling the rate of release of the bleach may provide for controlled
release of peroxide species to the wash solution. Such means could, for exarnple,
include controlling the release of any inorganic perhydrate salt, acting as a hydrogen
peroxide source, to the wash solution.
[0204] Suitable controlled release means can include confining the bleach to either the
compressed or non-compressed portions. Where more than one non-compressed portions
are present, the bleach may be confined to the first and/or second and/or optional
subsequent non-compressed portions.
[0205] Another mechanism for controlling the rate of release of bleach may be by coating
the bleach with a coating designed to provide the controlled release. The coating
may therefore, for example, comprise a poorly water soluble material, or be a coating
of sufficient thickness that the kinetics of dissolution of the thick coating provide
the controlled rate of release.
[0206] The coating material may be applied using various methods. Any coating material is
typically present at a weight ratio of coating material to bleach of from 1:99 to
1:2, preferably from 1:49 to 1:9.
[0207] Suitable coating materials include triglycerides (e.g. partially) hydrogenated vegetable
oil, soy bean oil, cotton seed oil) mono or diglycerides, microcrystalline waxes,
gelatin, cellulose, fatty acids and any mixtures thereof.
[0208] Other suitable coating materials can comprise the alkali and alkaline earth metal
sulphates, silicates and carbonates, including calcium carbonate and silicas.
[0209] A preferred coating material, particularly for an inorganic perhydrate salt bleach
source, comprises sodium silicate of SiO
2 : Na
2O ratio from 1.8 : 1 to 3.0 : 1, preferably 1.8:1 to 2.4:1, and/or sodium metasilicate,
preferably applied at a level of from 2% to 10%, (normally from 3% to 5%) of SiO
2 by weight of the inorganic perhydrate salt. Magnesium silicate can also be included
in the coating.
[0210] Any inorganic salt coating materials may be combined with organic binder materials
to provide composite inorganic salt/organic binder coatings. Suitable binders include
the C
10-C
20 alcohol ethoxylates containing from 5-100 moles of ethylene oxide per mole of alcohol
and more preferably the C
15-C
20 primary alcohol ethoxylates containing from 20 - 100 moles of ethylene oxide per
mole of alcohol.
[0211] Other preferred binders include certain polymeric materials. Polyvinylpyrrolidones
with an average molecular weight of from 12,000 to 700,000 and polyethylene glycols
(PEG) with an average molecular weight of from 600 to 5 x 10
6 preferably 1000 to 400,000 most preferably 1000 to 10,000 are examples of such polymeric
materials. Copolymers of maleic anhydride with ethylene, methylvinyl ether or methacrylic
acid, the maleic anhydride constituting at least 20 mole percent of the polymer are
further examples of polymeric materials useful as binder agents. These polymeric materials
may be used as such or in combination with solvents such as water, propylene glycol
and the above mentioned C
10-C
20 alcohol ethoxylates containing from 5 - 100 moles of ethylene oxide per mole. Further
examples of binders include the C
10-C
20 mono- and diglycerol ethers and also the C
10-C
20 fatty acids.
[0212] Cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxyethylcellulose,
and homo- or co-polymeric polycarboxylic acids or their salts are other examples of
binders suitable for use herein.
[0213] One method for applying the coating material involves agglomeration. Preferred agglomeration
processes include the use of any of the organic binder materials described hereinabove.
Any conventional agglomerator/mixer may be used including, but not limited to pan,
rotary drum and vertical blender types. Molten coating compositions may also be applied
either by being poured onto, or spray atomized onto a moving bed of bleaching agent.
[0214] Other means of providing the required controlled release include mechanical means
for altering the physical characteristics of the bleach to control its solubility
and rate of release. Suitable protocols could include compression, mechanical injection,
manual injection, and adjustment of the solubility of the bleach compound by selection
of particle size of any particulate component.
[0215] Whilst the choice of particle size will depend both on the composition of the particulate
component, and the desire to meet the desired controlled release kinetics, it is desirable
that the particle size should be more than 500 micrometers, preferably having an average
particle diameter of from 800 to 1200 micrometers.
[0216] Additional protocols for providing the means of controlled release include the suitable
choice of any other components of the detergent composition matrix such that when
the composition is introduced to the wash solution the ionic strength environment
therein provided enables the required controlled release kinetics to be achieved.
Metal-containing bleach catalyst
[0217] The compositions described herein which contain bleach as an active detergent component
may additionally contain as a preferred component, a metal containing bleach catalyst.
Preferably the metal containing bleach catalyst is a transition metal containing bleach
catalyst, more preferably a manganese or cobalt-containing bleach catalyst.
[0218] A suitable type of bleach catalyst is a catalyst comprising a heavy metal cation
of defined bleach catalytic activity, such as copper, iron cations, an auxiliary metal
cation having little or no bleach catalytic activity, such as zinc or aluminium cations,
and a sequestrant having defined stability constants for the catalytic and auxiliary
metal cations, particularly ethylenediaminetetraacetic acid, ethylenediaminetetra(methylenephosphonic
acid) and water-soluble salts thereof. Such catalysts are disclosed in U.S. Pat. 4,430,243.
[0219] Preferred types of bleach catalysts include the manganese-based complexes disclosed
in U.S. Pat. 5,246,621 and U.S. Pat. 5,244,594. Preferred examples of these catalysts
include Mn
IV2(u-O)
3(1,4,7-trimethyl-1,4,7-triazacyclononane)
2-(PF
6)
2, Mn
III2(u-O)
1(u-OAc)
2(1,4,7-trimethyl-1,4,7-triazacyclononane)
2-(ClO
4)
2, Mn
IV4(u-O)
6(1,4,7-triazacyclononane)
4-(ClO
4)
2, Mn
IIIMn
IV4(u-O)
1(u-OAc)
2-(1,4,7-trimethyl-1,4,7-triazacyclononane)
2-(ClO
4)
3, and mixtures thereof. Others are described in European patent application publication
no. 549,272. Other ligands suitable for use herein include 1,5,9-trimethyl-1,5,9-triazacyclododecane,
2-methyl-1,4,7-triazacyclononane, 2-methyl-1,4,7-triazacyclononane, 1,2,4,7-tetramethyl-1,4,7
-
triazacyclononane, and mixtures thereof.
[0220] The bleach catalysts useful in the compositions herein may also be selected as appropriate
for the present invention. For examples of suitable bleach catalysts see U.S. Pat.
4,246,612 and U.S. Pat. 5,227,084. See also U.S. Pat. 5,194,416 which teaches mononuclear
manganese (IV) complexes such as Mn(1,4,7-bimethyl-1,4,7-triazacyclononane)(OCH
3)
3-(PF
6).
[0221] Still another type of bleach catalyst, as disclosed in U.S. Pat. 5,114,606, is a
water-soluble complex of manganese (III), and/or (IV) with a ligand which is a non-carboxylate
polyhydroxy compound having at least three consecutive C-OH groups. Preferred ligands
include sorbitol, iditol, dulsitol, mannitol, xylithol, arabitol, adonitol, meso-erythritol,
meso-inositol, lactose, and mixtures thereof.
[0222] U.S. Pat. 5,114,611 teaches a bleach catalyst comprising a complex of transition
metals, including Mn, Co, Fe, or Cu, with an non-(macro)-cyclic ligand. Said ligands
are of the formula:

wherein R
1, R
2, R
3, and R
4 can each be selected from H, substituted alkyl and aryl groups such that each R
1-N=C-R
2 and R
3-C=N-R
4 form a five or six-membered ring. Said ring can further be substituted. B is a bridging
group selected from O, S. CR
5R
6, NR
7 and C=O, wherein R
5, R
6, and R
7 can each be H, alkyl, or aryl groups, including substituted or unsubstituted groups.
Preferred ligands include pyridine, pyridazine, pyrimidine, pyrazinc, imidazole, pyrazole,
and triazole rings. Optionally, said rings may be substituted with substituents such
as alkyl, aryl, alkoxy, halide, and nitro. Particularly preferred is the ligand 2,2'-bispyridyiamine.
[0223] Preferred bleach catalysts include Co, Cu, Mn, Fe,-bispyridylmethane and - bispyridylamine
complexes. Highly preferred catalysts include Co(2,2'-bispyridylamine)Cl
2, Di(isothiocyanato)bispyridylamine-cobalt (II), trisdipyridylamine-cobalt(II) perchlorate,
Co(2,2-bispyridylamine)
2O
2ClO
4, Bis-(2,2'-bispyridylamine) copper(II) perchlorate, tris(di-2-pyridylamine) iron(II)
perchlorate, and mixtures thereof.
[0224] Preferred examples include binuclear Mn complexes with tetra-N-dentate and bi-N-dentate
ligands, including N
4Mn
III(u-O)
2Mn
IVN
4)
+and [Bipy
2Mn
III(u-O)
2Mn
IVbipy
2]-(ClO
4)
3.
[0225] While the structures of the bleach-catalyzing manganese complexes of the present
invention have not been elucidated, it may be speculated that they comprise chelates
or other hydrated coordination complexes which result from the interaction of the
carboxyl and nitrogen atoms of the ligand with the manganese cation. Likewise, the
oxidation state of the manganese cation during the catalytic process is not known
with certainty, and may be the (+II), (+III), (+IV) or (+V) valence state. Due to
the ligands' possible six points of attachment to the manganese cation, it may be
reasonably speculated that multi-nuclear species and/or "cage" structures may exist
in the aqueous bleaching media. Whatever the form of the active Mn·ligand species
which actually exists, it functions in an apparently catalytic manner to provide improved
bleaching performances on stubborn stains such as tea, ketchup, coffee, wine, juice,
and the like.
[0226] Other bleach catalysts are described, for example, in European patent application,
publication no. 408,131 (cobalt complex catalysts), European patent applications,
publication nos. 384,503, and 306,089 (metallo-porphyrin catalysts), U.S. 4,728,455
(manganese/multidentate ligand catalyst), U.S. 4,711,748 and European patent application,
publication no. 224,952, (absorbed manganese on aluminosilicate catalyst), U.S. 4,601,845
(aluminosilicate support with manganese and zinc or magnesium salt), U.S. 4,626,373
(manganese/ligand catalyst), U.S. 4,119,557 (ferric complex catalyst), German Pat.
specification 2,054,019 (cobalt chelant catalyst) Canadian 866,191 (transition metal-containing
salts), U.S. 4,430,243 (chelants with manganese cations and non-catalytic metal cations),
and U.S. 4,728,455 (manganese gluconate catalysts).
[0227] Other preferred examples include cobalt (III) catalysts having the formula:
Co[(NH
3)
nM'
mB'
bT'
tQ
qP
p] Yy
wherein cobalt is in the +3 oxidation state; n is an integer from 0 to 5 (preferably
4 or 5; most preferably 5); M' represents a monodentate ligand; m is an integer from
0 to 5 (preferably 1 or 2; most preferably 1); B' represents a bidentate ligand; b
is an integer from 0 to 2; T' represents a tridentate ligand; t is 0 or 1; Q is a
tetradentate ligand; q is 0 or 1; P is a pentadentate ligand; p is 0 or 1; and n +
m + 2b + 3t + 4q + 5p = 6; Y is one or more appropriately selected counteranions present
in a number y, where y is an integer from 1 to 3 (preferably 2 to 3; most preferably
2 when Y is a -1 charged anion), to obtain a charge-balanced salt, preferred Y are
selected from the group consisting of chloride, nitrate, nitrite, sulfate, citrate,
acetate, carbonate, and combinations thereof; and wherein further at least one of
the coordination sites attached to the cobalt is labile under automatic dishwashing
use conditions and the remaining co-ordination sites stabilise the cobalt under automatic
dishwashing conditions such that the reduction potential for cobalt (III) to cobalt
(II) under alkaline conditions is less than 0.4 volts (preferably less than 0.2 volts)
versus a normal hydrogen electrode.
[0228] Preferred cobalt catalysts of this type have the formula:
[Co(NH
3)
n(M')
m] Y
y
wherein n is an integer from 3 to 5 (preferably 4 or 5; most preferably 5); M' is
a labile coordinating moiety, preferably selected from the group consisting of chlorine,
bromine, hydroxide, water, and (when m is greater than 1) combinations thereof; m
is an integer from 1 to 3 (preferably 1 or 2; most preferably 1); m+n = 6; and Y is
an appropriately selected counteranion present in a number y, which is an integer
from 1 to 3 (preferably 2 to 3; most preferably 2 when Y is a -1 charged anion), to
obtain a charge-balanced salt.
[0229] The preferred cobalt catalyst of this type useful herein are cobalt pentaamine chloride
salts having the formula [Co(NH
3)
5Cl] Y
y, and especially [Co(NH
3)
5Cl]Cl
2.
[0230] More preferred are the present invention compositions which utilize cobalt (III)
bleach catalysts having the formula:
[Co(NH
3)
n(M)
m(B)
b] Ty
wherein cobalt is in the +3 oxidation state; n is 4 or 5 (preferably 5); M is one
or more ligands coordinated to the cobalt by one site; m is 0, 1 or 2 (preferably
I ); B is a ligand co-ordinated to the cobalt by two sites; b is 0 or I (preferably
0), and when b=0, then m+n = 6, and when b=1, then m=0 and n=4; and T is one or more
appropriately selected counteranions present in a number y, where y is an integer
to obtain a charge-balanced salt (preferably y is I to 3; most preferably 2 when T
is a -1 charged anion); and wherein further said catalyst has a base hydrolysis rate
constant of less than 0.23 M
-1 s
-1 (25°C).
[0231] Preferred T are selected from the group consisting of chloride, iodide, I
3-, formate, nitrate, nitrite, sulfate, sulfite, citrate, acetate, carbonate, bromide,
PF
6-, BF
4-, B(Ph)
4-, phosphate, phosphite, silicate, tosylate, methanesulfonate, and combinations thereof.
Optionally, T can be protonated if more than one anionic group exists in T, e.g.,
HPO
42-, HCO
3-, H
2PO
4-, etc. Further, T may be selected from the group consisting of non-traditional inorganic
anions such as anionic surfactants (e.g., linear alkylbenzene sulfonates (LAS), alkyl
sulfates (AS), alkylethoxysulfonates (AES), etc.) and/or anionic polymers (e.g., polyacrylates,
polymethacrylates, etc.).
[0232] The M moieties include, but are not limited to, for example, F
-, SO
4-2, NCS
-, SCN
-, S
2O
3-2, NH
3, PO
43-, and carboxylates (which preferably are mono-carboxylates, but more than one carboxylate
may be present in the moiety as long as the binding to the cobalt is by only one carboxylate
per moiety, in which case the other carboxylate in the M moiety may be protonated
or in its salt form). Optionally, M can be protonated if more than one anionic group
exists in M (e.g., HPO
42-, HCO
3-, H
2PO
4-, HOC(O)CH
2C(O)O-, etc.) Preferred M moieties are substituted and unsubstituted C
1-C
30 carboxylic acids having the formulas:
RC(O)O-
wherein R is preferably selected from the group consisting of hydrogen and C
1-C
30 (preferably C
1-C
18) unsubstituted and substituted alkyl, C
6-C
30 (preferably C
6-C
18) unsubstituted and substituted aryl, and C
3-C
30 (preferably C
5-C
18) unsubstituted and substituted heteroaryl, wherein substituents are selected from
the group consisting of -NR'
3, -NR'
4+, -C(O)OR', -OR', -C(O)NR'
2, wherein R' is selected from the group consisting of hydrogen and C
1-C
6 moieties. Such substituted R therefore include the moieties -(CH
2)
nOH and -(CH
2)
nNR'
4+,
wherein n is an integer from 1 to 16, preferably from 2 to 10, and most preferably
from 2 to 5.
[0233] Most preferred M are carboxylic acids having the formula above wherein R is selected
from the group consisting of hydrogen, methyl, ethyl, propyl, straight or branched
C
4-C
12 alkyl, and benzyl. Most preferred R is methyl. Preferred carboxylic acid M moieties
include formic, benzoic, octanoic, nonanoic, decanoic, dodecanoic, malonic, maleic,
succinic, adipic, phthalic, 2-ethylhexanoic, naphthenoic, oleic, palmitic, triflate,
tartrate, stearic, butyric, citric, acrylic, aspartic, fumaric, lauric, linoleic,
lactic, malic, and especially acetic acid.
[0234] The B moieties include carbonate, di- and higher carboxylates (e.g., oxalate, malonate,
malic, succinate, maleate), picolinic acid, and alpha and beta amino acids (e.g.,
glycine, alanine, beta-alanine, phenylalanine).
[0235] Cobalt bleach catalysts useful herein are known, being described for example along
with their base hydrolysis rates, in M. L. Tobe, "Base Hydrolysis of Transition-Metal
Complexes",
Ady, Inorg. Bioinorg. Mech., (1983), 2, pages 1-94. For example, Table 1 at page 17, provides the base hydrolysis
rates (designated therein as k
OH) for cobalt pentaamine catalysts complexed with oxalate (k
OH= 2.5 x 10
-4 M
-1 s
-1 (25°C)), NCS- (k
OH= 5.0 x 10
-4 M
-1 s
-1 (25°C)), formate (k
OH= 5.8 x 10
- 4 M-1 s
-1 (25°C)), and acetate (k
OH= 9.6 x 10
-4 M
-1 s
-1 (25°C)). The most preferred cobalt catalyst useful herein are cobalt pentaamine acetate
salts having the formula [Co(NH
3)
5OAc] T
y, wherein OAc represents an acetate moiety, and especially cobalt pentaamine acetate
chloride, [Co(NH
3)
5OAc]Cl
2; as well as [Co(NH
3)
5OAc](OAc)
2; [Co(NH
3)
5OAc](PF
6)
2; [Co(NH
3)
5OAc](SO
4); [Co
- (NH
3)
5OAc](BF
4)
2; and [Co(NH
3)
5OAc](NO
3)
2 (herein "PAC").
[0236] These cobalt catalysts are readily prepared by known procedures, such as taught for
example in the Tobe article hereinbefore and the references cited therein, in U.S.
Patent 4,810,410, to Diakun et al, issued March 7,1989,
J. Chem. Ed. (1989),
66 (12), 1043-45; The Synthesis and Characterization of Inorganic Compounds, W.L. Jolly
(Prentice-Hall; 1970), pp. 461-3;
Inorg, Chem.,
18, 1497-1502 (1979);
Inorg, Chem.,
21, 2881-2885 (1982);
Inorg. Chem.,
18, 2023-2025 (1979); Inorg. Synthesis, 173-176 (1960); and
Journal of Physical Chemistry,
56, 22-25 (1952); as well as the synthesis examples provided hereinafter.
[0237] Cobalt catalysts suitable for incorporation into the detergent tablets of the present
invention may be produced according to the synthetic routes disclosed in U.S. Patent
Nos. 5,559,261, 5,581,005, and 5,597,936, the disclosures of which are herein incorporated
by reference.
[0238] These catalysts may be co-processed with adjunct materials so as to reduce the colour
impact if desired for the aesthetics of the product, or to be included in enzyme-containing
particles as exemplified hereinafter, or the compositions may be manufactured to contain
catalyst "speckles".
Organic polymeric compound
[0239] Organic polymeric compounds may be added as preferred components of the detergent
tablets in accord with the invention. By organic polymeric compound it is meant essentially
any polymeric organic compound commonly found in detergent compositions having dispersant,
anti-redeposition, soil release agents or other detergency properties.
[0240] Organic polymeric compound is typically incorporated in the detergent compositions
of the invention at a level of from 0.1% to 30%, preferably from 0.5% to 15%, most
preferably from 1% to 10% by weight of the compositions.
[0241] Examples of organic polymeric compounds include the water soluble organic homo- or
co-polymeric polycarboxylic acids, modified polycarboxylates or their salts in which
the polycarboxylic acid comprises at least two carboxyl radicals separated from each
other by not more than two carbon atoms. Polymers of the latter type are disclosed
in GB-A-1,596,756. Examples of such salts are polyacrylates of molecular weight 2000-10000
and their copolymers with any suitable other monomer units including modified acrylic,
fumaric, maleic, itaconic, aconitic, mesaconic, citraconic and methylenemalonic acid
or their salts, maleic anhydride, acrylamide, alkylene, vinylmethyl ether, styrene
and any mixtures thereof. Preferred are the copolymers of acrylic acid and maleic
anhydride having a molecular weight of from 20,000 to 100,000.
[0242] Preferred commercially available acrylic acid containing polymers having a molecular
weight below 15,000 include those sold under the tradename Sokalan PA30, PA20, PA15,
PA10 and Sokalan CP10 by BASF GmbH, and those sold under the tradename Acusol 45N,
480N, 460N by Rohm and Haas.
[0243] Preferred acrylic acid containing copolymers include those which contain as monomer
units: a) from 90% to 10%, preferably from 80% to 20% by weight acrylic acid or its
salts and b) from 10% to 90%, preferably from 20% to 80% by weight of a substituted
acrylic monomer or its salts having the general formula -[CR
2-CR
1(CO-O-R
3)]- wherein at least one of the substituents R
1, R
2 or R
3, preferably R
1 or R
2 is a 1 to 4 carbon alkyl or hydroxyalkyl group, R
1 or R
2 can be a hydrogen and R
3 can be a hydrogen or alkali metal salt. Most preferred is a substituted acrylic monomer
wherein R
1 is methyl, R
2 is hydrogen (i.e. a methacrylic acid monomer). The most preferred copolymer of this
type has a molecular weight of 3500 and contains 60% to 80% by weight of acrylic acid
and 40% to 20% by weight of methacrylic acid.
[0244] The polyamine and modified polyamine compounds are useful herein including those
derived from aspartic acid such as those disclosed in EP-A-305282, EP-A-305283 and
EP-A-351629.
[0245] Other optional polymers may polyvinyl alcohols and acetates both modified and non-modified,
cellulosics and modified cellulosics, polyoxyethylenes, polyoxypropylenes, and copolymers
thereof, both modified and non-modified, terephthalate esters of ethylene or propylene
glycol or mixtures thereof with polyoxyalkylene units.
[0246] Suitable examples are disclosed in US patent Nos. 5,591,703 , 5,597,789 and 4,490,271.
Soil Release Agents
[0247] Suitable polymeric soil release agents include those soil release agents having:
(a) one or more nonionic hydrophile components consisting essentially of (i) polyoxyethylene
segments with a degree of polymerization of at least 2, or (ii) oxypropylene or polyoxypropylene
segments with a degree of polymerization of from 2 to 10, wherein said hydrophile
segment does not encompass any oxypropylene unit unless it is bonded to adjacent moieties
at each end by ether linkages, or (iii) a mixture of oxyalkylene units comprising
oxyethylene and from 1 to 30 oxypropylene units, said hydrophile segments preferably
comprising at least 25% oxyethylene units and more preferably, especially for such
components having 20 to 30 oxypropylene units, at least 50% oxyethylene units; or
(b) one or more hydrophobe components comprising (i) C
3 oxyalkylene terephthalate segments, wherein, if said hydrophobe components also comprise
oxyethylene terephthalate, the ratio of oxyethylene terephthalate:C
3 oxyalkylene terephthalate units is 2:1 or lower, (ii) C
4-C
6 alkylene or oxy C
4-C
6 alkylene segments, or mixtures therein, (iii) poly (vinyl ester) segments, preferably
polyvinyl acetate, having a degree of polymerization of at least 2, or (iv) C
1-C
4 alkyl ether or C
4 hydroxyalkyl ether substituents, or mixtures therein, wherein said substituents are
present in the form of C
1-C
4 alkyl ether or C
4 hydroxyalkyl ether cellulose derivatives, or mixtures therein, or a combination of
(a) and (b).
[0248] Typically, the polyoxyethylene segments of (a)(i) will have a degree of polymerization
of from 200, although higher levels can be used, preferably from 3 to 150, more preferably
from 6 to 100. Suitable oxy C
4-C
6 alkylene hydrophobe segments include, but are not limited to, end-caps of polymeric
soil release agents such as MO
3S(CH
2)
nOCH
2CH
2O-, where M is sodium and n is an integer from 4-6, as disclosed in U.S. Patent 4,721,580,
issued January 26, 1988 to Gosselink.
[0249] Polymeric soil release agents useful herein also include cellulosic derivatives such
as hydroxyether cellulosic polymers, copolymeric blocks of ethylene terephthalate
or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate,
and the like. Such agents are commercially available and include hydroxyethers of
cellulose such as METHOCEL (Dow). Cellulosic soil release agents for use herein also
include those selected from the group consisting of C
1-C
4 alkyl and C
4 hydroxyalkyl cellulose; see U.S. Patent 4,000,093, issued December 28, 1976 to Nicol,
et al.
[0250] Soil release agents characterized by poly(vinyl ester) hydrophobe segments include
graft copolymers of poly(vinyl ester), e.g., C
1-C
6 vinyl esters, preferably poly(vinyl acetate) grafted onto polyalkylene oxide backbones,
such as polyethylene oxide backbones. See European Patent Application 0 219 048, published
April 22, 1987 by Kud, et al.
[0251] Another suitable soil release agent is a copolymer having random blocks of ethylene
terephthalate and polyethylene oxide (PEO) terephthalate. The molecular weight of
this polymeric soil release agent is in the range of from 25,000 to 55,000. See U.S.
Patent 3,959,230 to Hays, issued May 25, 1976 and U.S. Patent 3,893,929 to Basadur
issued July 8, 1975.
[0252] Another suitable polymeric soil release agent is a polyester with repeat units of
ethylene terephthalate units contains 10-15% by weight of ethylene terephthalate units
together with 90-80% by weight of polyoxyethylene terephthalate units, derived from
a polyoxyethylene glycol of average molecular weight 300-5,000.
[0253] Another suitable polymeric soil release agent is a sulfonated product of a substantially
linear ester oligomer comprised of an oligomeric ester backbone of terephthaloyl and
oxyalkyleneoxy repeat units and terminal moieties covalently attached to the backbone.
These soil release agents are described fully in U.S. Patent 4,968,451, issued November
6, 1990 to J.J. Scheibel and E.P. Gosselink. Other suitable polymeric soil release
agents include the terephthalate polyesters of U.S. Patent 4,711,730, issued December
8, 1987 to Gosselink et al, the anionic end-capped oligomeric esters of U.S. Patent
4,721,580, issued January 26, 1988 to Gosselink, and the block polyester oligomeric
compounds of U.S. Patent 4,702,857, issued October 27, 1987 to Gosselink. Other polymeric
soil release agents also include the soil release agents of U.S. Patent 4,877,896,
issued October 31, 1989 to Maldonado et al, which discloses anionic, especially sulfoarolyl,
end-capped terephthalate esters.
[0254] Another soil release agent is an oligomer with repeat units of terephthaloyl units,
sulfoisoterephthaloyl units, oxyethyleneoxy and oxy-1,2-propylene units. The repeat
units form the backbone of the oligomer and are preferably terminated with modified
isethionate end-caps. A particularly preferred soil release agent of this type comprises
one sulfoisophthaloyl unit, 5 terephthaloyl units, oxyethyleneoxy and oxy-1,2-propyleneoxy
units in a ratio of from 1.7 to 1.8, and two end-cap units of sodium 2-(2-hydroxyethoxy)-ethanesulfonate.
Heavy metal ion sequestrant
[0255] The detergent tablets of the invention preferably contain as an optional component
a heavy metal ion sequestrant. By heavy metal ion sequestrant it is meant herein components
which act to sequester (chelate) heavy metal ions. These compor.ents may also have
calcium and magnesium chelation capacity, but preferentially they show selectivity
to binding heavy metal ions such as iron, manganese and copper.
[0256] Heavy metal ion sequestrants are generally present at a level of from 0.005% to 20%,
preferably from 0.1% to 10%, more preferably from 0.25% to 7.5% and most preferably
from 0.5% to 5% by weight of the compositions.
[0257] Heavy metal ion sequestrants, which are acidic in nature, having for example phosphonic
acid or carboxylic acid functionalities, may be present either in their acid form
or as a complex/salt with a suitable counter cation such as an alkali or alkaline
metal ion, ammonium, or substituted ammonium ion, or any mixtures thereof.
[0258] Preferably any salts/complexes are water soluble. The molar ratio of said counter
cation to the heavy metal ion sequestrant is preferably at least 1:1.
[0259] Suitable heavy metal ion sequestrants for use herein include organic phosphonates,
such as the amino alkylene poly (alkylene phosphonates), alkali metal ethane 1-hydroxy
disphosphonates and nitrilo trimethylene phosphonates. Preferred among the above species
are diethylene triamine penta (methylene phosphonate), ethylene diamine tri (methylene
phosphonate) hexamethylene diamine tetra (methylene phosphonate) and hydroxy-ethylene
1,1 diphosphonate.
[0260] Other suitable heavy metal ion sequestrant for use herein include nitrilotriacetic
acid and polyaminocarboxylic acids such as ethylenediaminotetracetic acid, ethylenetriamine
pentacetic acid, ethylenediamine disuccinic acid, ethylenediamine diglutaric acid,
2-hydroxypropylenediamine disuccinic acid or any salts thereof.
[0261] Especially preferred is ethylenediamine-N,N'-disuccinic acid (EDDS) or the alkali
metal, alkaline earth metal, ammonium, or substituted ammonium salts thereof, or mixtures
thereof. Preferred EDDS compounds are the free acid form and the sodium or magnesium
salt or complex thereof.
Crystal growth inhibitor component
[0262] The detergent tablets preferably contain a crystal growth inhibitor component, preferably
an organodiphosphonic acid component, incorporated preferably at a level of from 0.01%
to 5%, more preferably from 0.1% to 2% by weight of the compositions.
[0263] By organo diphosphonic acid it is meant herein an organo diphosphonic acid which
does not contain nitrogen as part of its chemical structure. This definition therefore
excludes the organo aminophosphonates, which however may be included in compositions
of the invention as heavy metal ion sequestrant components.
[0264] The organo diphosphonic acid is preferably a C
1-C
4 diphosphonic acid, more preferably a C
2 diphosphonic acid, such as ethylene diphosphonic acid, or most preferably ethane
1-hydroxy-1,1-diphosphonic acid (HEDP) and may be present in partially or fully ionized
form, particularly as a salt or complex.
Water-soluble sulfate salt
[0265] The detergent tablet optionally contains a water-soluble sulfate salt. Where present
the water-soluble sulfate salt is at the level of from 0.1% to 40%, more preferably
from 1% to 30%, most preferably from 5% to 25% by weight of the compositions.
[0266] The water-soluble sulfate salt may be essentially any salt of sulfate with any counter
cation. Preferred salts are selected from the sulfates of the alkali and alkaline
earth metals, particularly sodium sulfate.
Alkali Metal Silicate
[0267] According to an embodiment of the present invention an alkali metal silicate is an
essential component of the detergent tablet. In other embodiments of the present invention
the presence of an alkali metal silicate is optional. A preferred alkali metal silicate
is sodium silicate having an SiO
2:Na
2O ratio of from 1.8 to 3.0, preferably from 1.8 to 2.4, most preferably 2.0. Sodium
silicate is preferably present at a level of less than 20%, preferably from 1% to
15%, most preferably from 3% to 12% by weight of SiO
2. The alkali metal silicate may be in the form of either the anhydrous salt or a hydrated
salt.
[0268] Alkali metal silicate may also be present as a component of an alkalinity system.
[0269] The alkalinity system also preferably contains sodium metasilicate, present at a
level of at least 0.4% SiO
2 by weight. Sodium metasilicate has a nominal SiO
2 : Na
2O ratio of 1.0. The weight ratio of said sodium silicate to said sodium metasilicate,
measured as SiO
2, is preferably from 50:1 to 5:4, more preferably from 15:1 to 2:1, most preferably
from 10:1 to 5:2.
Colourant
[0270] The term 'colourant', as used herein, means any substance that absorbs specific wavelengths
of light from the visible light spectrum. Such colourants when added to a detergent
composition have the effect of changing the visible colour and thus the appearance
of the detergent composition. Colourants may be for example either dyes or pigments.
Preferably the colourants are stable in composition in which they are to be incorported.
Thus in a composition of high pH the colourant is preferably alkali stable and in
a composition of low pH the colourant is preferably acid stable.
[0271] The compressed portion and/or non compressed may contain a colourant, a mixture of
colourants, coloured particles or mixture of coloured particles such that the compressed
portion and the non-compressed portion have different visual appearances. Preferably
one of either the compressed portion or the non-compressed comprises a colourant.
[0272] Where the non-compressed portion comprises two or more compositions of active detergent
components, preferably at least one of either the first and second and/or subsequent
compositions comprises a colourant. Where both the first and second and/or subsequent
compositions comprise a colourant it is preferred that the colourants have a different
visual appearance.
[0273] Where present the coating layer preferably comprises a colourant. Where the compressed
portion and the coating layer comprise a colourant, it is preferred that the colourants
provide a different visual effect.
[0274] Examples of suitable dyes include reactive dyes, direct dyes, azo dyes. Preferred
dyes include phthalocyanine dyes, anthraquinone dye, quinoline dyes, monoazo, disazo
and polyazo. More preferred dyes include anthraquinone, quinoline and monoazo dyes.
Preferred dyes include SANDOLAN E-HRL 180% (tradename), SANDOLAN MILLING BLUE (tradename),
TURQUOISE ACID BLUE (tradename) and SANDOLAN BRILLIANT GREEN (tradename) all available
from Clariant UK, HEXACOL QUINOLINE YELLOW (tradename) and HEXACOL BRILLIANT BLUE
(tradename) both available from Pointings, UK, ULTRA MARINE BLUE (tradename) available
from Holliday or LEVAFIX TURQUISE BLUE EBA (tradename) available from Bayer, USA.
[0275] The colourant may be incorporated into the compressed and/or non-compressed portion
by any suitable method. Suitable methods include mixing all or selected active detergent
components with a colourant in a drum or spraying all or selected active detergent
components with the colourant in a rotating drum.
[0276] Colourant when present as a component of the compressed portion is present at a level
of from 0.001% to 1.5%, preferably from 0.01% to 1.0%, most preferably from 0.1% to
0.3%. When present as a component of the non-compressed portion, colourant is generally
present at a level of from 0.001% to 0.1%, more preferably from 0.005% to 0.05%, most
preferably from 0.007% to 0.02%. When present as a component of the coating layer,
colourant is present at a level of from 0.01% to 0.5%, more preferably from 0.02%
to 0.1%, most preferably from 0.03% to 0.06%.
Corrosion inhibitor compound
[0277] The detergent tablets of the present invention suitable for use in dishwashing methods
may contain corrosion inhibitors preferably selected from organic silver coating agents,
particularly paraffin, nitrogen-containing corrosion inhibitor compounds and Mn(II)
compounds, particularly Mn(II) salts of organic ligands.
[0278] Organic silver coating agents are described in PCT Publication No. WO94/16047 and
copending European application No. EP-A-690122. Nitrogen-containing corrosion inhibitor
compounds are disclosed in copending European Application no. EP-A-634,478. Mn(II)
compounds for use in corrosion inhibition are described in copending European Application
No. EP-A-672 749.
[0279] Organic silver coating agent may be incorporated at a level of from 0.05% to 10%,
preferably from 0.1% to 5% by weight of the total composition.
[0280] The functional role of the silver coating agent is to form 'in use' a protective
coating layer on any silverware components of the washload to which the compositions
of the invention are being applied. The silver coating agent should hence have a high
affinity for attachment to solid silver surfaces, particularly when present in as
a component of an aqueous washing and bleaching solution with which the solid silver
surfaces are being treated.
[0281] Suitable organic silver coating agents herein include fatty esters of mono- or polyhydric
alcohols having from 1 to 40 carbon atoms in the hydrocarbon chain.
[0282] The fatty acid portion of the fatty ester can be obtained from mono- or polycarboxylic
acids having from 1 to 40 carbon atoms in the hydrocarbon chain Suitable examples
of monocarboxylic fatty acids include behenic acid, stearic acid, oleic acid, palmitic
acid, myristic acid, lauric acid, acetic acid, propionic acid, butyric acid, isobutyric
acid, Valerie acid, lactic acid, glycolic acid and β,β'-dihydroxyisobutyric acid.
Examples of suitable polycarboxylic acids include: n-butyl-malonic acid, isocitric
acid, citric acid, maleic acid, malic acid and succinic acid.
[0283] The fatty alcohol radical in the fatty ester can be represented by mono- or polyhydric
alcohols having from 1 to 40 carbon atoms in the hydrocarbon chain. Examples of suitable
fatty alcohols include; behenyl, arachidyl, cocoyl, oleyl and lauryl alcohol, ethylene
glycol, glycerol, ethanol, isopropanol, vinyl alcohol, diglycerol, xylitol, sucrose,
erythritol, pentaerythritol, sorbitol or sorbitan.
[0284] Preferably, the fatty acid and/or fatty alcohol group of the fatty ester adjunct
material have from 1 to 24 carbon atoms in the alkyl chain.
[0285] Preferred fatty esters herein are ethylene glycol, glycerol and sorbitan esters wherein
the fatty acid portion of the ester normally comprises a species selected from behenic
acid, stearic acid, oleic acid, palmitic acid or myristic acid.
[0286] The glycerol esters are also highly preferred. These are the mono-, di- or tri-esters
of glycerol and the fatty acids as defined above.
[0287] Specific examples of fatty alcohol esters for use herein include: stearyl acetate,
palmityl di-lactate, cocoyl isobutyrate, oleyl maleate, oleyl dimaleate , and tallowyl
proprionate. Fatty acid esters useful herein include: xylitol monopalmitate, pentaerythritol
monostearate, sucrose monostearate, glycerol monostearate, ethylene glycol monostearate,
sorbitan esters. Suitable sorbitan esters include sorbitan monostearate, sorbitan
palmitate, sorbitan monolaurate, sorbitan monomyristate, sorbitan monobehenate, sorbitan
mono-oleate, sorbitan dilaurate, sorbitan distearate, sorbitan dibehenate, sorbitan
dioleate, and also mixed tallowalkyl sorbitan mono- and di-esters.
[0288] Glycerol monostearate, glycerol mono-oleate, glycerol monopalmitate, glycerol monobehenate,
and glycerol distearate are preferred glycerol esters herein.
[0289] Suitable organic silver coating agents include triglycerides, mono or diglycerides,
and wholly or partially hydrogenated derivatives thereof, and any mixtures thereof.
Suitable sources of fatty acid esters include vegetable and fish oils and animal fats.
Suitable vegetable oils include soy bean oil, cotton seed oil, castor oil, olive oil,
peanut oil, safflower oil, sunflower oil, rapeseed oil, grapeseed oil, palm oil and
com oil.
[0290] Waxes, including microcrystalline waxes are suitable organic silver coating agents
herein. Preferred waxes have a melting point in the range from 35°C to 110°C and comprise
generally from 12 to 70 carbon atoms. Preferred are petroleum waxes of the paraffin
and microcrystalline type which are composed of long-chain saturated hydrocarbon compounds.
[0291] Alginates and gelatin are suitable organic silver coating agents herein.
[0292] Dialkyl amine oxides such as C
12-C
20 methylamine oxide, and dialkyl quaternary ammonium compounds and salts, such as the
C
12-C
20 methylammonium halides are also suitable.
[0293] Other suitable organic silver coating agents include certain polymeric materials.
Polyvinylpyrrolidones with an average molecular weight of from 12,000 to 700,000,
polyethylene glycols (PEG) with an average molecular weight of from 600 to 10,000,
polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole,
and cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxyethylcellulose
are examples of such polymeric materials.
[0294] Certain perfume materials, particularly those demonstrating a high substantiv ity
for metallic surfaces, are also useful as the organic silver coating agents herein.
[0295] Polymeric soil release agents can also be used as an organic silver coating agent.
[0296] A preferred organic silver coating agent is a paraffin oil, typically a predominantly
branched aliphatic hydrocarbon having a number of carbon atoms in the range of from
20 to 50; preferred paraffin oil selected from predominantly branched C
25-45 species with a ratio of cyclic to noncyclic hydrocarbons of from 1:10 to 2:1, preferably
from 1:5 to 1:1. A paraffin oil meeting these characteristics, having a ratio of cyclic
to noncyclic hydrocarbons of 32:68, is sold by Wintershall, Salzbergen, Germany, under
the trade name WINOG 70.
Nitrogen-containing corrosion inhibitor compounds
[0297] Suitable nitrogen-containing corrosion inhibitor compounds include imidazole and
derivatives thereof such as benzimidazole, 2-heptadecyl imidazole and those imidazole
derivatives described in Czech Patent No. 139, 279 and British Patent GB-A-1,137,741,
which also discloses a method for making imidazole compounds.
[0298] Also suitable as nitrogen-containing corrosion inhibitor compounds are pyrazole compounds
and their derivatives, particularly those where the pyrazole is substituted in any
ofthe 1, 3, 4 or 5 positions by substituents R
1, R
3, R
4 and R
5 where R
1 is any of H, CH
2OH, CONH
3, or COCH
3, R
3 and R
5 are any of C
1-C
20 alkyl or hydroxyl, and R
4 is any of H, NH
2 or NO
2.
[0299] Other suitable nitrogen-containing corrosion inhibitor compounds include benzotriazole,
2-mercaptobenzothiazole, 1-phenyl-5-mercapto-1,2,3,4-tetrazole, thionalide, morpholine,
melamine, distearylamine, stearoyl stearamide, cyanuric acid, aminotriazole, aminotetrazole
and indazole.
[0300] Nitrogen-containing compounds such as amines, especially distearylamine and ammonium
compounds such as ammonium chloride, ammonium bromide, ammonium sulphate or diamonium
hydrogen citrate are also suitable.
Mn(II) corrosion inhibitor compounds
[0301] The detergent tablets may contain an Mn(II) corrosion inhibitor compound. The Mn(II)
compound is preferably incorporated at a level of from 0.005% to 5% by weight, more
preferably from 0.01% to 1%, most preferably from 0.02% to 0.4% by weight of the compositions.
Preferably, the Mn(II) compound is incorporated at a level to provide from 0.1 ppm
to 250 ppm, more preferably from 0.5 ppm to 50 ppm, most preferably from 1 ppm to
20 ppm by weight of Mn(II) ions in any bleaching solution.
[0302] The Mn (II) compound may be an inorganic salt in anhydrous, or any hydrated forms.
Suitable salts include manganese sulphate, manganese carbonate, manganese phosphate,
manganese nitrate, manganese acetate and manganese chloride. The Mn(II) compound may
be a salt or complex of an organic fatty acid such as manganese acetate or manganese
stearate.
[0303] The Mn(II) compound may be a salt or complex of an organic ligand. In one preferred
aspect the organic ligand is a heavy metal ion sequestrant. In another preferred aspect
the organic ligand is a crystal growth inhibitor.
Other corrosion inhibitor compounds
[0304] Other suitable additional corrosion inhibitor compounds include, mercaptans and diols,
especially mercaptans with 4 to 20 carbon atoms including lauryl mercaptan, thiophenol,
thionapthol, thionalide and thioanthranol. Also suitable are saturated or unsaturated
C
10-C
20 fatty acids, or their salts, especially aluminium tristearate. The C
12-C
20 hydroxy fatty acids, or their salts, are also suitable. Phosphonated octa-decane
and other anti-oxidants such as betahydroxytoluene (BHT) are also suitable.
[0305] Copolymers of butadiene and maleic acid, particularly those supplied under the trade
reference no. 07787 by Polysciences Inc have been found to be of particular utility
as corrosion inhibitor compounds.
Hydrocarbon oils
[0306] Another preferred active detergent component for use in the present invention is
a hydrocarbon oil, typically a predominantly long chain, aliphatic hydrocarbons having
a number of carbon atoms in the range of from 20 to 50; preferred hydrocarbons are
saturated and/or branched; preferred hydrocarbon oil selected from predominantly branched
C
25-45 species with a ratio of cyclic to noncyclic hydrocarbons of from 1:10 to 2:1, preferably
from 1:5 to 1:1. A preferred hydrocarbon oil is paraffin. A paraffin oil meeting the
characteristics as outlined above, having a ratio of cyclic to noncyclic hydrocarbons
of 32:68, is sold by Wintershall, Salzbergen, Germany, under the trade name WINOG
70.
Water-soluble bismuth compound
[0307] The detergent tablets of the present invention suitable for use in dishwashing methods
may contain a water-soluble bismuth compound, preferably present at a level of from
0.005% to 20%, more preferably from 0.01% to 5%, most preferably from 0.1% to 1% by
weight of the compositions.
[0308] The water-soluble bismuth compound may be essentially any salt or complex of bismuth
with essentially any inorganic or organic counter anion. Preferred inorganic bismuth
salts are selected from the bismuth trihalides, bismuth nitrate and bismuth phosphate.
Bismuth acetate and citrate are preferred salts with an organic counter anion.
Enzyme Stabilizing System
[0309] Preferred enzyme-containing compositions herein may comprise from 0.001% to 10%,
preferably from 0.005% to 8%, most preferably from 0.01% to 6%, by weight of an enzyme
stabilizing system. The enzyme stabilizing system can be any stabilizing system which
is compatible with the detersive enzyme. Such stabilizing systems can comprise calcium
ion, boric acid, propylene glycol, short chain carboxylic acid, boronic acid, chlorine
bleach scavengers and mixtures thereof. Such stabilizing systems can also comprise
reversible enzyme inhibitors, such as reversible protease inhibitors.
Lime soap dispersant compound
[0310] The compositions of active detergent components may contain a lime soap dispersant
compound, preferably present at a level of from 0.1 % to 40% by weight, more preferably
1% to 20% by weight, most preferably from 2% to 10% by weight of the compositions.
[0311] A lime soap dispersant is a material that prevents the precipitation of alkali metal,
ammonium or amine salts of fatty acids by calcium or magnesium ions. Preferred lime
soap disperant compounds are disclosed in PCT Application No. WO93/08877.
Suds suppressing system
[0312] The detergent tblets of the present invention, when formulated for use in machine
washing compositions, preferably comprise a suds suppressing system present at a level
of from 0.01% to 15%, preferably from 0.05% to 10%, most preferably from 0.1% to 5%
by weight of the composition.
[0313] Suitable suds suppressing systems for use herein may comprise essentially ar.y known
antifoam compound, including, for example silicone antifoam compounds, 2-alkyl and
alcanol antifoam compounds. Preferred suds suppressing systems and antifoam compounds
are disclosed in PCT Application No. WO93/08876 and EP-A-705 324.
Polymeric dye transfer inhibiting agents
[0314] The detergent tablets herein may also comprise from 0.01% to 10 %, preferably from
0.05% to 0.5% by weight of polymeric dye transfer inhibiting agents.
[0315] The polymeric dye transfer inhibiting agents are preferably selected from polyamine
N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinylpyrrolidonepolymers
or combinations thereof.
Optical brightener
[0316] The detergent tablets suitable for use in laundry washing methods as described herein,
also optionally contain from 0.005% to 5% by weight of certain types of hydrophilic
optical brighteners.
[0317] Hydrophilic optical brighteners useful herein include those having the structural
formula:

wherein R
1 is selected from anilino, N-2-bis-hydroxyethyl and NH-2-hydroxyethyl; R
2 is selected from N-2-bis-hydroxyethyl, N-2-hydroxyethyl-N-methylamino, morphilino,
chloro and amino; and M is a salt-forming cation such as sodium or potassium.
[0318] When in the above formula, R
1 is anilino, R
2 is N-2-bis-hydroxyethyl and M is a cation such as sodium, the brightener is 4,4',-bis[(4-anilino-6-(N-2-bis-hydroxyethyl)-s-triazine-2-yl)amino]-2,2'-stilbenedisulfonic
acid and disodium salt. This particular brightener species is commercially marketed
under the tradename Tinopal-UNPA-GX by Ciba-Geigy Corporation. Tinopal-UNPA-GX is
the preferred hydrophilic optical brightener useful in the detergent compositions
herein.
[0319] When in the above formula, R
1 is anilino, R
2 is N-2-hydroxyethyl-N-2-methylamino and M is a cation such as sodium, the brightener
is 4,4'-bis[(4-anilino-6-(N-2-hydroxyethyl-N-methylamino)-s-triazine-2-yl)amino]2,2'-stilbenedisulfonic
acid disodium salt. This particular brightener species is commercially marketed under
the tradename Tinopal 5BM-GX by Ciba-Geigy Corporation,
[0320] When in the above formula, R
1 is anilino, R
2 is morphilino and M is a cation such as sodium, the brightener is 4,4'-bis[(4-anilino-6-morphilino-s-triazine-2-yl)amino]2,2'-stilbenedisulfonic
acid, sodium salt. This particular brightener species is commercially marketed under
the tradename Tinopal AMS-GX by Ciba Geigy Corporation.
Clay softening system
[0321] The detergent tablets suitable for use in laundry cleaning methods may contain a
clay softening system comprising a clay mineral compound and optionally a clay flocculating
agent.
[0322] The clay mineral compound is preferably a smectite clay compound. Smectite clays
are disclosed in the US Patents No.s 3,862,058, 3,948,790, 3,954,632 and 4,062,647.
European Patents No.s EP-A-299,575 and EP-A-313,146 in the name of the Procter and
Gamble Company describe suitable organic polymeric clay flocculating agents.
Cationic fabric softening agents
[0323] Cationic fabric softening agents can also be incorporated into compositions in accordance
with the present invention which are suitable for use in methods of laundry washing.
Suitable cationic fabric softening agents include the water insoluble tertiary amines
or dilong chain amide materials as disclosed in GB-A-1 514 276 and EP-B-0 011 340.
[0324] Cationic fabric softening agents are typically incorporated at total levels of from
0.5% to 15% by weight, normally from 1% to 5% by weight.
Other optional ingredients
[0325] Other optional ingredients suitable for inclusion in the compositions of the invention
include perfumes and filler salts, with sodium sulfate being a preferred filler salt.
pH of the compositions
[0326] The detergent tablets of the present invention are preferably not formulated to have
an unduly high pH, in preference having a pH measured as a 1% solution in distilled
water of from 8.0 to 12.5, more preferably from 9.0 to 11.8, most preferably from
9.5 to 11.5.
[0327] In another aspect of the present invention the compressed and non-compressed portions
are formulated to deliver different pH.
Machine dishwashing method
[0328] Any suitable methods for machine washing or cleaning soiled tableware are envisaged.
A preferred machine dishwashing method comprises treating soiled articles selected
from crockery, glassware, silverware, metallic items, cutlery and mixtures thereof,
with an aqueous liquid having dissolved or dispensed therein an effective amount of
a detergent tablet in accord with the invention. By an effective amount of the detergent
tablet it is meant from 8g to 60g of product dissolved or dispersed in a wash solution
of volume from 3 to 10 litres, as are typical product dosages and wash solution volumes
commonly employed in conventional machine dishwashing methods. Preferably the detergent
tablets are from 15g to 40g in weight, more preferably from 20g to 35g in weight.
Laundry washing method
[0329] Machine laundry methods herein typically comprise treating soiled laundry with an
aqueous wash solution in a washing machine having dissolved or dispensed therein an
effective amount of a machine laundry detergent tablet composition in accord with
the invention. By an effective amount of the detergent tablet composition it is meant
from 40g to 300g of product dissolved or dispersed in a wash solution of volume from
5 to 65 litres, as are typical product dosages and wash solution volumes commonly
employed in conventional machine laundry methods.
[0330] In a preferred use aspect a dispensing device is employed in the washing method.
The dispensing device is charged with the detergent product, and is used to introduce
the product directly into the drum of the washing machine before the commencement
of the wash cycle. Its volume capacity should be such as to be able to contain sufficient
detergent product as would normally be used in the washing method.
[0331] Once the washing machine has been loaded with laundry the dispensing device containing
the detergent product is placed inside the drum. At the commencement of the wash cycle
of the washing machine water is introduced into the drum and the drum periodically
rotates. The design of the dispensing device should be such that it permits containment
of the dry detergent product but then allows release of this product during the wash
cycle in response to its agitation as the drum rotates and also as a result of its
contact with the wash water.
[0332] To allow for release of the detergent product during the wash the device may possess
a number of openings through which the product may pass. Alternatively, the device
may be made of a material which is permeable to liquid but impermeable to the solid
product, which will allow release of dissolved product. Preferably, the detergent
product will be rapidly released at the start of the wash cycle thereby providing
transient localised high concentrations of product in the drum of the washing machine
at this stage of the wash cycle.
[0333] Preferred dispensing devices are reusable and are designed in such a way that container
integrity is maintained in both the dry state and during the wash cycle.
[0334] Alternatively, the dispensing device may be a flexible container, such as a bag or
pouch. The bag may be of fibrous construction coated with a water impermeable protective
material so as to retain the contents, such as is disclosed in European published
Patent Application No. 0018678. Alternatively it may be formed of a water-insoluble
synthetic polymeric material provided with an edge seal or closure designed to rupture
in aqueous media as disclosed in European published Patent Application Nos. 0011500,
0011501, 0011502, and 0011968. A convenient form of water frangible closure comprises
a water soluble adhesive disposed along and sealing one edge of a pouch formed of
a water impermeable polymeric film such as polyethylene or polypropylene.
Examples
Abbreviations used in Examples
[0335] In the detergent compositions, the abbreviated component identifications have the
following meanings:
STPP |
Sodium tripolyphosphate |
Citrate |
Tri-sodium citrate dihydrate |
Bicarbonate |
Sodium hydrogen carbonate |
Citric Acid |
Anhydrous Citric acid |
Carbonate |
Anhydrous sodium carbonate |
Silicate |
Amorphous Sodium Silicate (SiO2:Na2O ratio = 1.6-3.2) |
Metasilicate |
Sodium metasilicate (SiO2:Na2O ratio = 1.0) |
PB1 |
Anhydrous sodium perborate monohydrate |
PB4 |
Sodium perborate tetrahydrate of nominal formula NaBO2.3H2O.H2O2 |
Plurafac |
C13-C15 mixed ethoxylated/propoxylated fatty alcohol with an average degree of ethoxylation
of 3.8 and an average degree of propoxylation of 4.5, sold under the tradename Plurafac
by BASF |
Tergitol |
Nonionic surfactant available under the tradename Tergitol 15S9 from Union Carbide |
SLF18 |
Epoxy-capped poly(oxyalkylated) alcohol of Example III of WO 94/22800 wherein 1,2-epoxydodecane
is substituted for 1,2-epoxydecane available under the tradename Polytergent SLF18D
from OLIN. |
TAED |
Tetraacetyl ethylene diamine |
HEDP |
Ethane 1-hydroxy-1,1-diphosphonic acid |
DETPMP |
Diethyltriamine penta (methylene) phosphonate, marketed by monsanto under the tradename
Dequest 2060 |
PAAC |
Pentaamine acetate cobalt (III) salt |
BzP |
Benzoyl Peroxide |
Paraffin |
Paraffin oil sold under the tradename Winog 70 by Wintershall. |
Protease |
Proteolytic enzyme |
Amylase |
Amylolytic enzyme. |
BTA |
Benzotriazole |
PA30 |
Polyacrylic acid of average molecular weight approximately 4,500 |
480N |
Random copolymer of 7:3 acrylate/methacrylate, average molecular weight 3,500 |
Sulphate |
Anhydrous sodium sulphate. |
PEG 3000 |
Polyethylene Glycol molecular weight approximately 3000 available from Hoechst |
PEG 6000 |
Polyethylene Glycol molecular weight approximately 6000 available from Hoechst |
Sugar |
Household sucrose |
Gelatine |
Gelatine Type A, 65 bloom strength available from Sigma |
CMC |
Carboxymethylcellulose |
Dodecandioic Acid |
C12 dicarboxylic acid |
Adipic Acid |
C6 dicarboxylic acid |
Lauric Acid |
C12 monocarboxylic acid |
|
pH |
Measured as a 1% solution in distilled water at 20°C |
[0336] In the following examples all levels are quoted as % by weight of the compressed
portion, the non-compressed portion or the coating layer:
Example 1
[0337] The following illustrates examples detergent tablets of the present invention suitable
for use in a dishwashing machine.
[0338] The compressed portion is prepared by delivering the composition of active detergent
components to a punch cavity of a modified 12 head rotary tablet press and compressing
the composition at a pressure of 13KN/cm
2. The modified tablet press provides tablet wherein the compressed portion has a mould.
For the purposes of Example A to F the non-compressed portion is in particulate form.
The non-compressed portion is accurately delivered to the mould of the compressed
portion using a nozzle feeder. The non-compressed portion is adhered to the compressed
portion by coating the non-compressed portion with a coating layer which contacts
the compressed portion.

Example 2
[0339] The compressed portion is prepared by delivering the composition of active detergent
components to a punch cavity of a modified 12 head rotary tablet press and compressing
the composition at a pressure of 13KN/cm
2. The modified tablet press provides tablet wherein the compressed portion has a mould.
For the purposes of Examples G to K the non-compressed portion comprises active detergent
components and a binding agent. The non-compressed portion is then poured into the
mould of the compressed portion. The detergent tablet is then subjected to a conditioning
step, during which time the non-compressed portion hardens.
|
G |
H |
I |
J |
K |
L |
Compressed portion |
|
|
|
|
|
|
STPP |
- |
55.10 |
52.0 |
52.80 |
50.00 |
38.20 |
Citrate |
26.40 |
- |
- |
- |
- |
- |
Carbonate |
- |
14.0 |
16.0 |
15.40 |
18.40 |
15.00 |
Silicate |
26.40 |
14.80 |
15.0 |
12.60 |
10.00 |
10.10 |
Protease |
- |
- |
- |
1.0 |
- |
- |
Amylase |
0.6 |
0.75 |
0.75 |
0.95 |
2.0 |
0.85 |
PB1 |
1.56 |
12.50 |
12.20 |
12.60 |
15.70 |
11.00 |
PB4 |
6.92 |
- |
- |
- |
- |
- |
Nonionic |
1.50 |
1.5 |
1.50 |
1.65 |
0.80 |
1.65 |
PAAC |
- |
0.016 |
0.016 |
0.012 |
- |
0.008 |
TAED |
4.33 |
- |
- |
- |
1.30 |
- |
HEDP |
0.67 |
- |
- |
- |
- |
0.92 |
DETPMP |
0.65 |
- |
- |
- |
- |
- |
Paraffin |
0.42 |
0.50 |
0.5 |
0.55 |
0.50 |
- |
BTA |
0.24 |
0.30 |
0.3 |
0.33 |
0.33 |
- |
PA30 |
3.2 |
- |
- |
- |
- |
- |
Perfume |
- |
- |
- |
0.05 |
0.20 |
0.2 |
Sulphate |
24.05 |
- |
2.00 |
- |
10.68 |
22.07 |
Misc/water to balance |
|
|
|
|
|
|
Weight (g) |
20.0g |
20.0g |
20.0g |
20.0g |
22g |
30.0g |
Non-compressed portion |
Tergitol |
- |
- |
21.5 |
18.92 |
- |
- |
PEG 3000 |
89.40 |
- |
- |
- |
- |
- |
PEG 6000 |
|
86.9 |
- |
- |
- |
- |
BzP |
10.60 |
11.00 |
- |
- |
20.00 |
20.00 |
Sugar |
- |
- |
53.4 |
29.04 |
65.00 |
65.00 |
Gelatine |
- |
- |
15.01 |
30.00 |
5.00 |
5.00 |
Starch |
- |
- |
- |
10.00 |
- |
- |
Water |
- |
- |
10.00 |
10.00 |
10.00 |
10.00 |
Misc./balance |
|
|
|
|
|
|
Weight (g) |
2.5g |
5.0g |
2.5g |
2.5g |
3g |
3g |
|
Total weight (g) of tablet |
22.5g |
25g |
22.5g |
22.5g |
25g |
33g |