[0001] This invention relates to laundry additive products in the form of sheet substrates
coated or impregnated with solidified detergent compositions, and is especially concerned
with the separation of the solid impregnating and/or coating medium from the substrate
during its passage through the processing equipment.
[0002] Laundry additive products in impregnated or coated sheet substrate form are known
in the art, being disclosed in e.g. British Patent Specification Nos. 1,586,769, 2040983
and European Patent Application Nos. 0013450 and 0098129 the latter published 11.01.84.
The compositions forming the coating or impregnating media for these products are
primarily organic in nature and are arranged to be solid at ambient temperatures whilst
being releasable from the substrate by dissolution, melting, or abrasion when added
to an aqueous laundry liquor. The products are also characterised by a high loading
factor, i.e. a weight ratio of coating or impregnating medium to substrate of ,3:1
so that the physical characteristics of the solidified coating or impregnating medium
itself have to be taken into account in the handling of the coated or impregnated
substrate, particularly when continuous manufacture of the product takes place.
[0003] Continuous manufacture of a sheet substrate product of this type involves the processing
of a moving web of material, and necessitates sliding and rolling contact between
the coated web and portions of the equipment. Under certain conditions it has been
found that separation of the coating medium from the sheet substrate can occur, particularly
at points where the coated product experiences an abrupt change of direction e.g.
where the moving web separates from the contact surface. This separation manifests
itself as a flaky deposit on equipment and is undesirable from a number of standpoints,
as it is wasteful of coating medium, is unsightly and may affect the fuctioning of
the equipment. A need therefore exists for a processing aid which will prevent or
minimise this separation from the substrate of normally solid organic coating or impregnating
compositions.
[0004] The use of normally solid organic processing aids is disclosed in the above mentioned
British Patent Specification Nos. 1,586,769 and 2040983 but these materials, whilst
satisfactory in assisting the coating and/or impregnation of flexible sheet substrates,
such as non woven textile webs, have not been found useful in preventing or minimising
the flaking of product from such webs or the deposit of the separated product on processing
equipment.
[0005] Surprisingly, the Applicants have now found that low levels of certain liquid polyols
are useful in preventing the flaking of compositions from flexible substrates in detergent
additive products of the type disclosed in the above mentioned British Patent Specifications.
This reduction in flaking is particularly noticeable when coated substrate products
incorporating the invention are exposed to sudden angular deflection as in folding
or movement around small diameter rolls.
[0006] According to the present invention there is provided a laundry additive product comprising
a normally solid detergent composition comprising a solid matrix having a melting
point greater than 30°C and less than 80°C, in which matrix is dispersed solid particles
of size >150 pm, said solid particles comprising from 5% to 50% by weight of the composition,
said composition being in water releasable combination with a flexible sheet substrate,
the weight ratio of said composition to said substrate lying in the range from 1:2
to 12:1 wherein said composition includes a liquid processing aid selected from polyols
of MWt ,180 and boiling point (at atmospheric pressure) of at least 100°C in an amount
of from 0.5% to 5.0% by weight of the composition.
[0007] Preferably, the liquid polyols display a solubility of less than 0.1 % by weight
in non polar solvents such as hexane and benzene and preferably also the liquid polyols
display a high solubility in water. Most preferably the liquid polyols are completely
miscible with water. The invention finds its greatest utility in those products which
have a high loading factor i.e. those in which the weight ratio of the composition
to the substrate is greater than 1:1, more preferably from 2:1 to 10:1, most preferably
from 3:1 to 8:1.
[0008] In the context of the present invention, a material is defined as normally solid
if a block of the material is self supporting at a temperature of 30°C and below.
For the purposes of this invention the term 'water- releasable combination' is taken
to mean a combination capable of being separated by water through solution, dispersion,
leaching, softening or melting.
[0009] The laundry additive products of the present invention comprise a detergent composition
of defined characteristics in water releasable combination with a flexible sheet type
substrate.
[0010] The detergent composition useful in the present invention include those exemplified
in British Patent Specifications Nos. 1,586,769 and 2040983 which relate to compositions
comprising an organic peroxy acid bleach precursor (so-called bleach activator) in
water releasable combination with a flexible sheet substrate. Mixtures of nonionic
and cationic surfactants as well as peroxy acid bleach precursors are a highly preferred
components of compositions of the present invention.
[0011] In the laundry additive products of the present invention the substrate is preferably
absorbent and the composition is impregnated therein. Impregnation can be carried
out in any convenient manner and many methods are known in the art, such as application
as a solution or dispersion from an organic solvent followed by volatilisation of
the solvent. However, the preferred method is by forming a melt of those components
having a melting point below 100°C, dispersing the remainder of the components in
the melt, applying this melt to the substrate and cooling the impregnated substrate
to provide the final product.
[0012] Coated sheet products of this type, particularly when manufactured on continuous
processing equipment, are prone to suffer separation of the coating from the substrate.
This separation normally manifests itself as a flaky/dusty deposit on surrounding
equipment and suraces and most frequently occurs when the coated product undergoes
abrupt changes of orientation e.g. around small diameter rolls or in apparatus designed
to fold the coated substrate. The severity of the problem is a function of many variables,
such as the nature of the coating material, the absorbent capacity and physical form
of the substrate, the weight of coating being applied and the stresses to which the
coated substrate is subjected.
[0013] It has now been found that this flaky deposit can be prevented or considerably reduced
by the inclusion in the detergent composition forming the coating impregnating medium
of a liquid polyol processing aid of Molecular weight ;180 and boiling point >100°C
at atmospheric pressure, in an amount of from 0.5% to 5.0% by weight of the composition,
preferably from 0.5% to 3.0% by weight. Suitable polyols include glycerol and mono
C
l-C
4 alkyl ethers and esters thereof, diethylene glycol, 1,2 propane diol and 2-methyl
propane 1,2-diol. Preferred materials are glycerol and diethylene glycol.
[0014] Whilst the mechanism of the beneficial effect provided by the liquid polyols is not
fully understood, it is believed that it involves a modification of the composition
of the particulate solid and solidified liquid phases that result when the detergent
composition is solidified after the coating and impregnation step.
[0015] The potential suitability of polyols for preventing flaking can be gauged by a screening
test method which simulates the stress on coated substrates that is likely to be encountered
during manufacture. The test method involves weighing the product lost and assigning
a 'flaking grade' on the basis of the value obtained.
[0016] In the method a standard product is used which comprises a non woven apertured rayon
sheet of basis weight 35 g/m
2 and size 350 mm x 230 mm impregnated with a composition comprising:

[0017] The Test method uses the following:
1 Gallenkamp shaker plus clamps
1 Glass lined open-ended vessel - height 400 mm, length 250 mm, width 100 mm
1 sheet of black card - length 250 mm, width 100 mm
1 digital balance accurate to 0.01 g
1 sheet of coated/impregnated product
Procedure
[0018] Weigh the black card accurately on the digital balance and record. Set up the tank
below the clamps on the shaker and place the black card on the base of the tank. Clamp
the sheet to the shaker. Switch on the machine at its minimum setting for 1 minute,
collecting all the flake falling off the sheet on the black card. Weigh the card plus
flake accurately on the digital balance and record and deduct the initial card weight
from the card plus flake weight.
[0019] Flaking grades are assigned on a 1-10 scale as follows, the higher numbers donating
improvement in flaking grade. Product having a flaking grade <5 is regarded as unsatisfactory.

On this basis various materials graded as follows:

[0020] Preferred materials are glycerol and diethylene glycol used in amounts of 0.1-0.3
g/sheet, corresponding to a range of from 0.5% to 1.6% based on the weight of the
detergent composition.
[0021] The detergent composition is normally solid i.e. can be formed into a body which
is self supporting at temperatures of 30°C and below. It is composed of a solidifed
liquid mass, which has a melting point lying between 30°C and 80°C in which are dispersed
solid particles of size <150 pm, preferably <50 itm.
[0022] The detergent composition comprises any of the conventional functional components
normally used in laundry detergents such as surfactants of anionic, nonionic, cationic
amphoteric or zwitterionic type, suds modifiers, detergent builder salts, chelating
agents, peroxygen bleaches, organic peroxy bleach precursors, anti-redeposition agents,
antibacterial agents, fabric softening and antistatic agents, optical brighteners,
anticorrosion agents, enzymes, perfumes, dyes and pigments.
[0023] Most of the above components, if present in the additive product of the invention,
form the solid particulate phase which may be organic or inorganic in type or may
be a mixture of the two. Certain components such as nonionic surfactants, suds modifiers
and certain anti-redeposition agents are solids having melting points within the temperature
range required for the solidified liquid mass and so can be employed both as functional
components and as carriers for the remainder.
[0024] With respect to the surfactants, those of anionic type can be natural or synthetic
in origin whilst nonionic surfactants can be either semi-polar or alkylene oxide condensates.
Examples of each of these classes of compounds are disclosed in Laughlin & Heuring
US Patent No. 3,929,678 issued 30 December 1975. Cationic surfactants can include
amine salts, quaternary nitrogen and phosphorus compounds and ternary sulphonium compounds.
The invention is particularly useful in additive products incorporating a quaternary
ammonium surfactant as the or part of the solid particles.
[0025] The nonionic surfactants used in the compositions may be alkoxylated aliphatic alcohols,
alkyl phenols, esters, amides and fatty acids having an HLB within the range 8.0-17.0.
The aliphatic alcohols include linear and branched chain primary and secondary C
a-C
22 alcohols, the alkyl phenols are the C
6―C
12 alkyl phenols, and the fatty esters, fatty amides and fatty acids are those having
a C
12―C
18 alkyl group in the acyl residue. The preferred alkoxylating group is ethylene oxide.
[0026] Suitable nonionic surfactants based on aliphatic alcohols are condensation products
of primary and secondary alcohols with from 4 to 30 moles of ethylene oxide. The alkyl
chain of the aliphatic alcohol can either be straight or branched and generally contains
from 8 to 22 carbon atoms. Examples of such ethoxylated alcohols include the condensation
product of myristyl alcohol with 10 moles of ethylene oxide per mole of alcohol and
the condensation product of 9 moles of ethylene oxide with coconut alcohol (a mixture
of fatty alcohols with alkyl chains varying in length from 10 to 14 carbon atoms).
Examples of nonionic surfactants of this type include those commercially available
under the Trade Names Tergitol 15-S-9, marketed by Union Carbide Corporation, Neodol
45E9, marketed by Shell Chemical Company, and Kyro EOB, marketed by The Procter &
Gamble Company. Other suitable alcohol ethoxylates include:-

[0027] Alcohol ethoxylates such as those disclosed in British Patent Specification No. 1,462,134
are also useful.
[0028] Suitable alkyl phenol ethoxylates include the condensation products of alkyl phenols
having an alkyl group containing from 6 to 12 carbon atoms in either a straight chain
or branched chain configuration with ethylene oxide, said ethylene oxide being present
in an amount equal to 8 to 20 moles of ethylene oxide per mole of alkyl phenol. The
alkyl substituent in such compounds can be derived, for example, from polymerized
propylene, di-isobutylene, and the like. Examples of compounds of this type include
nonyl phenol condensed with 9.5 moles of ethylene oxide per mole of nonyl phenol;
dodecylphenol condensed with 12 moles of ethylene oxide per mole of phenol; and di-isooctyl
phenol condensed with 15 moles of ethylene oxide per mole of phenol. Nonionic surfactants
of this type include those commercially available under the trade names Igepal CO-630,
marketed by the GAF Corporation, and Triton X-45, X-114, X-100, and X-102, all marketed
by the Rohm & Haas Company.
[0029] Other suitable phenol ethoxylates include:-

[0030] Suitable fatty acid ethoxylates include coconut fatty acid (E
5) and oleic fatty acid (E
lo), while ester ethoxylates include:

[0031] Other nonionic surfactants useful herein include the condensation products of ethylene
oxide with the product resulting from the reaction of propylene oxide and ethylene
diamine, and the condensation product of ethylene oxide with the product resulting
from the condensation of propylene oxide with propylene glycol. Surfactants of this
type are available commercially from the Wyandotte Chemicals Corporation under the
Registered Trade Marks "Tetronic" and "Pluronic" respectively.
[0032] Particularly preferred nonionic surfactants as components of the compositions useful
in the present invention are the primary linear and branched chain primary alcohol
ethoxylates, such as C,
4-C,
5 linear alcohols condensed with 7-15 moles of ethylene oxide available from Shell
Oil Co. under the Trade Name "Dobanol" and the C
16―C
13 branched chain alcohol ethoxylates obtainable from Liquichimica SA under the Trade
Name "Lial". The cationic surfactants forming preferred components of the compositions
useful in the present invention have the empirical formula
[0033]

wherein each R' is a hydrophobic organic group containing alkyl chains, alkenyl chains,
alkyl benzyl chains, alkyl phenyl chains, ether linkages, alkylene groups, alkenylene
groups, ester linkages, or amide linkages totalling from 8 to 22 carbon atoms and
which may additionally contain or be attached to a polyethylene oxide chain containing
up to 20 ethoxy groups, m is a number from one to three provided that no more than
one R' in a molecule can have more than 16 carbon atoms when m is 2 and no more than
12 carbon atoms when m is 3, R
2 is an alkyl or hydroxyalkyl group containing from 1 to 4 carbon atoms or a benzyl
group, with no more than one R
2 in a molecule being benzyl, and x is a number from 1 to 3, Y is selected from

and Z is a water-soluble anion selected from halide, methosulphate, carboxylate, hydroxide,
or nitrate, particularly preferred being chloride, bromide or iodide anions, in a
number to give electrical neutrality of the cationic component. The particular cationic
component to be included in a given system depends to a large extent upon the particular
nonionic component to be used in this system, and is selected such that it is at least
water-dispersible, or preferably water-soluble, when mixed with said nonionic surfactant.
It is preferred that the cationic component be substantially free of hydrazinium groups.
Mixtures of these cationic materials may also be used in the compositions of the present
invention.
[0034] When used in combination with nonionic surfactants, these cationic components provide
excellent soil removal characteristics, confer static control benefits to the laundered
fabrics, and inhibit the transfer of dyes among the laundered fabrics in the wash
solution.
[0035] In preferred cationic materials, L is equal to 1 and Y is

However, L may be greater than 1, such as in cationic components containing 2 or 3
cationic charge centres.
[0036] Where Y is

and m = 1, it is preferred that x is equal to 3. R
2 is normally a methyl group but a preferred structure is where one R
2 group is hydroxy ethyl. Cationic surfactants of this mono long chain type include
those in which R' is a C
10―C
10 alkyl group more preferably a C
10―C
16 alkyl group. Particularly preferred compositions of this class include C
12 and C
14 alkyl trimethyl ammonium bromide, C
12 alkyl dimethyl hydroxy ethyl ammonium bromide and C
12 alkyl dimethyl hydroxypropyl ammonium bromide and their counterparts based on middle-cut
coconut alcohol as the source of the alkyl group. Other counter ions such as methosulphate
and carboxylate can also be used particularly with the hydroxyalkyl-substituted compounds.
[0037] When m is equal to 2, only one of the R' chains should be longer than 16 carbon atoms.
Thus, ditallow- dimethylammonium salts used conventionally as fabric softeners and
static control agents in detergent compositions, are unsuitable as the cationic component
in surfactant mixtures. Preferred di-long chain cationics of this type include those
in which x is equal to 2 and R
2 is a methyl group. Particularly preferred cationic materials of this class include
are those in which R, is C
8―C
12 alkyl such as the di-C
a alkyl dimethylammonium salt, the di-C
10 alkyldimethylammonium salts and the di-C
12 alkyldimethylammonium salts materials.
[0038] Where m is equal to 3, only one of the R' chains can be greater than 12 carbon atoms
in length. The reason for this chain length restriction, as is also the case with
the di-long chain cationics described above, is the relative insolubility of these
tri- and di-long chain materials. Where tri-long chain alkyl materials are used, it
is preferred that x is equal to 1 and that R
2 is a methyl group. In these compositions it is preferred that R' is a C
8 to C
11 alkyl group. Particularly preferred tri-long chain cationics include trioctylmethylammonium
halide, and tridecylmethylammonium halide.
[0039] Cationic components in which m is equal to 1 and the hydrophobic group R, is interrupted
by ester linkages are disclosed in US-A-4260529. Particularly preferred cationic surfactants
of this type are the choline ester derivatives having the following formula

as well as those wherein the ester linkage in the above formula is replaced with a
reverse ester, amide or reverse amide linkage.
[0040] Particularly preferred examples of this type of cationic surfactant include stearoyl
choline ester quaternary ammonium halide (R
3 = C
17 alkyl), palmitoyl choline ester quaternary ammonium halides (R
3 = C
16 alkyl), myristoyl choline ester quaternary ammonium halides (R
3 = C
13 alkyl), lauroyl choline ester ammonium halides (R
3 = C" alkyl), and tallowoyl choline ester quaternary ammonium halides (R
3 = C
16―C
18 alkyl).
[0041] The above described cationic components are useful in nonionic/cationic surfactant
mixtures which have a ratio of nonionic to cationic of from 1:2 to 20:1. Preferably,
nonionic to cationic ratios of from 10:1 to 1:1 are used, more preferably from 5:1
1 to 3:2, most preferably from 10:3 to 10:5. These cationic surfactants may also be
used in the detergent systems defined in US Patent No. 4,259,217, in nonionic to cationic
ratios of from 8:1 to 20:1.
[0042] In compositions incorporating mixtures of nonionic and cationic surfactants it is
preferred that the amount of the nonionic-cationic mixture is such that the surfactant
mixture:substrate weight ratio lies in the range 10:1 to 1:5, preferably from 10:1
to 1:2, and most preferably from 5:1 to 1:1. In preferred executions using non-woven
sheet substrates of approximately 805
CM2 plan area and 3 grs/sheet basis weight, the loading of nonionic-cationic surfactant
mixture is in the range 5-15 grs/sheet.
[0043] Suds modifiers useful in the detergent compositions can be of the suds boosting,
suds stabilising or suds suppressing type. Examples of the first type include the
C
12-C
18 fatty acid amides and alkanolamides, the second type is exemplified by the C
'2-C
'6 alkyl dilower alkyl amine oxides and the third type by C
20-C
24 fatty acids, certain ethylene oxide-propylene oxide copolymers such as the "Pluronic"
series, silicones, silica-silicone blends, micro-crystalline waxes, triazines and
mixtures of any of the foregoing.
[0044] Preferred suds suppressing additives are described in US Patent 3,933,672, issued
January 20, 1976, relative to a silicone suds controlling agent. The silicone material
can be represented by alkylated polysiloxane materials such as silica aerogels and
xerogels and hydrophobic silicas of various types. The silicone material can be described
as siloxane having the formula:

wherein x is from 20 to 2,000, and R and R' are each alkyl or aryl groups, especially
methyl, ethyl, propyl, butyl and phenyl. The polydimethylsiloxanes (R and R' are methyl)
having a molecular weight within the range of from 200 to 200,000, and higher, are
all useful as suds controlling agents. Additional suitable silicone materials which
exhibit useful suds controlling properties, are those wherein the side chain groups
R and R' are alkyl, aryl, or mixed alkyl and aryl hydrocarbyl groups, examples including
diethyl-, dipropyl-, dibutyl-, methyl-, ethyl-, and phenylmethylpolysiloxanes. Additional
useful silicone suds controlling agents can be represented by a mixture of an alkylated
siloxane, as referred to hereinbefore, and solid silica. Such mixtures are prepared
by affixing the silicone to the surface of the solid silica. A preferred silicone
suds controlling agent is represented by a hydrophobic silanated (most preferably
trimethylsilanated) silica having a particle size in the range from 10 nanometers
to 20 nanometers and a specific surface area above 50 m
2/g intimately admixed with dimethyl silicone fluid having a molecular weight in the
range from 500 to 200,000 at a weight ratio of silicone to silanated silica of from
19:1 to 1:2. The silicone suds suppressing agent is advantageously releasably incorporated
in a water-soluble or water-dispersible, substantially non- surface-active detergent-impermeable
carrier.
[0045] Particularly useful suds suppressors are the self-emulsifying silicone suds suppressors,
described in US Patent No. 4,136,045. An example of such a compound is DB-544, commercially
available from Dow Corning, wich is a siloxane/glycol copolymer.
[0046] Suds modifiers as described above are incorporated at levels of up to approxiamtely
5%, preferably from 0.1 to 2% by weight of the cationic-nonionic surfactant mixture.
[0047] Detergent builder salts can be inorganic or organic in type but the crystalline nature
of inorganic builder salts, and hence the difficulty of incorporating them by coating
or impregnation puts constraints on the amounts which can be included in the products
of the invention. This results in a practical upper limit on the weight ratio of inorganic
builder to substrate of about 5:1. Organic builder salts such as citrates, mellitates,
phytates, nitrilo triacetates, carboxymethyloxy succinates, polyacrylates and polyhydroxy-
acrylates can be incorporated at higher levels, i.e. up to a weight ratio of builder
to substrate of about 8: 1.
[0048] Chelating agents that can be incorporated include citric acid, nitrilotriacetic and
ethylene diamine tetra acetic acids and the salts, organic phosphonate derivatives
such as those disclosed in Diehl US Patent No. 3,213,030 issued 19 October, 1965;
Roy US Patent No. 3,433,021 issued 14 January, 1968; Gedge US Patent No. 3,292,121
issued 9 January, 1968; and Bersworth US Patent No. 2,599,807 issued 10 June, 1952,
and carboxylic acid builder salts such as those disclosed in Diehl US Patent No. 3,308,067
issued 7 March, 1967. Preferred chelating agents include nitrilotriacetic acid (NTA),
nitrilotrimethylene phosphonic acid (NTMP), ethylene diamine tetra methylene phosphonic
acid (EDTMP) and diethylene triamine penta methylene phosphonic acid (DETPMP), and
these are incorporated in amounts such that the substrate chelating agent weight ratio
lies in the range 20:1 to 1:5, preferably 5:1 to 1:5 and most preferably 3:1 to 1:1.
[0049] Inorganic peroxygen bleaches which can be incorporated include those which are true
peroxysalts such as alkali metal monopersulphates as well as salts which include hydrogen
peroxide, such as sodium perborate monohydrate and tetrahydrate, sodium percarbonate,
sodium persilicate and sodium perpyrophosphate.
[0050] Clathrates such as that comprising 4Na
1SO
4: 2H
2O
1: 1 NaCl can also be incorporated provided that moisture is excluded from the compositions.
Mixing of the bleach with the other components can be employed in certain instances
but where materials reactive towards the bleach such as organic peroxy acid bleach
precursors are included, spatial separation of the bleach from these materials is
necessary.
[0051] Organic peroxy acid bleach precursors are preferred components of laundry products
of the invention and any of the precursors disclosed in British Patent Specification
Nos. 1,586,769 and 2040983 and European Patent Application No. 0098129, published
11.01.84, can be included. Preferred precursors include tetra acetyl alkylene diamine,
in which the alkylene group can contain from 1 to 6 carbon atoms tetra acetyl glycoluril,
sodium p-C,-C
9 acyloxybenzene sulphonates in which the alkyl portion of the acyl group may be linear
or branched, penta acetyl glucose, octa acetyl lactose and mixtures of any of these.
[0052] Certain polybasic acids have been found to enhance the bleaching effect of organic
peroxyacids, examples being EDTMP, NTMP and DETPMP. However, not all chelating polybasic
acids are useful in this respect, while certain poorly-chelating polybasic acids,
notably succinic acid, and glutaric acid, do show efficacy.
[0053] The level of usage of the precursor will naturally be dependent on a number of factors
e.g. the size of the fabric load in the machine, the level of bleaching performance
desired, the amount of perhydroxyl ion in the wash solution, the bleaching efficacy
of the organic peroxy species derived from the precursor and the efficiency of conversion
of the precursor into that peroxy species. It is conventional with inorganic peroxy
bleaches to provide a level of available oxygen in solution from 50 ppm to 350 ppm
by weight for heavy duty laundry purposes. However, when using organic peroxy bleaches
a level of available oxygen provided by the organic peroxy compound may lie in the
range from 2 ppm to 100 ppm, levels of from 3 ppm to 30 ppm being appropriate under
conventional US washing conditions while levels of from 20 ppm to 50 ppm are more
commonly used under European washing conditions. This level of available oxygen should
be attained within the normal wash cycle time i.e. within 5-25 minutes depending on
the particular wash cycle being employed.
[0054] For a machine having a liquid capacity in use of 20 to 30 litres, such a level of
available oxygen requires the delivery of from 1 gr to 20 gr of organic peroxy compound
precursor assuming quantitative conversion. Preferably a single unit of substrate
should be capable of accommodating the desired level of precursor and any adjuvants
and additives that it is necessary to incorporate into the product, although the number
of units to be used to deliver a given quantity of precursors is a matter of choice.
Normally the weight of precursor per delivery will lie in the range 3 to 10 grs, preferably
from 4 to 6 grs.
[0055] Anti redeposition and soil suspension agents also constitute preferred components
of the additive compositions of the invention. Cellulose derivatives such as methyl
cellulose, carboxymethyl cellulose and hydroxy ethyl cellulose are examples of soil
suspension agents and suitable antiredeposition agents are provided by homo- or co-polymeric
polycarboxylic acids or their salts in which at least two carboxyl radicals are present
separated by not more than two carbon atoms. Polyethylene glycols of MWt 1,000-10,000
particularly of MWt 4,000-10,000 are also useful particulate soil suspension agents
and function as such even if included primarily as processing aids.
[0056] Highly preferred polymeric polycarboxylic acids are copolymers of maleic acid or
maleic anhydride with methyl vinyl ether, ethyl vinyl ether or acrylic acid, the polymers
having a molecular weight in the range from 12,000 to 1;500,000.
[0057] A further description of suitable polymeric polycarboxylic acids is provided in the
Applicants' European Patent Application Publication No. 63017. Levels of incorporation
of these antiredeposition agents are such as to provide agent:substrate ratios of
2:1 to 1:20, preferably 1:2 to 1:10.
[0058] Suitable antibacterial agents are quaternary ammonium compounds such as cetyl pyridinium
chloride, cetyl trimethyl ammonium bromide and C
8-C,
8 alkyl benzyl dimethyl ammonium chloride, typically incorporated in weight ratios
of agent to substrate of from 1:1 to 1:10.
[0059] A wide range of fabric softeners and antistatic agents can be included as optional
compounds. Exemplary cationic nitrogen compounds include the di-C,
6-C,
8 alkyl, di-C,-C
4 alkyl quaternary ammonium salts, imidazolinium salts and non-nitrogenous materials
such as the sorbitan esters of C
16―C
18 fatty acids. These are normally incorporated at softener to substrate weight ratios
of 5:1 to 1:1.
[0060] Optical brighteners may be anionic or nonionic in type and are added at levels of
from 0.05 to 1.0 grs per sheet preferably 0.1 to 0.5 grs per sheet.
[0061] Anionic fluorescent brightening agents are well-known materials, examples of which
are disodium 4,4'-bis-(2-diethanolamino-4-anilino-s-triazin-6-ylamino) stilbene-2:2'-disulphonate,
disodium 4,4'-bis-(2-morpholino-4-anilino-s-triazin-6-ylamino)stilbene-2:2'-disulphonate,
disodium 4,4'-bis-(2,4-dianilino-s-triazin-6-ylamino) stilbene-2:2'-di-sulphonate,
disodium 4,4'-bis-(2-anilino-4-(N-methyl-N-2-hydroxyethyl- amino) stiibene-2,2'-di-suiphonate,
disodium 4,4'-bis-(4-phenyl-2,1,3-triazol-2-yl)-stilbene-2,2'- disulphonate, disodium
4,4'-bis(2'-anilino-4-(1-methyl-2-hydroxyethylamino)-s-triazin-6-ylamino)stilbene-2,2'-disulphonate,
sodium 2(stilbyl-4"-(naptho-1',2':4,5)-1,2,3-triazol-2"-sulphonate and di-sodium 4,4'-
bis(2-sulphonato styryl)biphenyl.
[0062] Other fluorescers to which the invention can be applied include the 1,3-diaryl pyrazolines
and 7-alkyl- aminocourmarins.
[0063] A preferred fluorescer is the anionic material available from Ciba Geigy S.A. under
the trade name Tinopal (RTM) CBS and mixtures thereof with materials available under
the trade names Tinopal (RTM) EMS and Blankophor (RTM) MBEN, the latter being sold
by Farbenfabriken Bayer AG.
[0064] Other preferred optional ingredients include the multifunctional photoactivator/dyes
belonging to the porphine class of general formula

wherein each X is (=N-) or (=CY-), and the total number of (=N-) groups is 0, 1, 2,
or 4; wherein each Y, independently, is hydrogen or meso substituted alkyl, cycloalkyl,
aralkyl, aryl, alkaryl or heteroaryl; wherein each R, independently, is hydrogen or
pyrrole substituted alkyl, cycloalkyl, aralkyl, aryl, alkaryl or heteroraryl, or wherein
adjacent pairs of R's are joined together with orthoarylene groups to form pyrrole
substituted alicyclic or heterocyclic rings; wherein A is 2(H) atoms bonded to diagonally
opposite nitrogen atoms, or Zn(II), Cd(II), Mg(II), Ca(II), AI(III), Sc(lll), or Sn(IV);
wherein B is an anionic, nonionic or cationic solubilizing group substituted into
Y or R; wherein M is a counterion to the solubilizing groups; wherein, when B is cationic,
M is an anion and s is from 1 to 8; when B is nonionic, B is polyethoxylate, M is
zero, s is from 1 to 8, and the number of condensed ethylene oxide molecules per porphine
molecule is from 8 to 50; when B is anionic and proximate, M is cationic and s is
from 3 to 8; when B is anionic and remote, M is cationic and s is from 2 to 8; and
when B is sulphonate the number of sulphonate groups is no greater than the number
of aromatic and heterocyclic substituent groups.
[0065] As used herein, a solubilizing group attached to a carbon atoms displaced more than
5 carbon atoms away from the porphine core is referred to as "remote"; otherwise it
is "proximate".
[0066] Highly preferred materials of this general type are the zinc phthalocyanine tri-
and tetrasulphonates and mixtures thereof. Materials of this general class were originally
disclosed for use in detergent compositions in British Patents 1,372,035 and 1,408,144
and are discussed in detail in European Patent Application 3861. The photo-activators
can provide bleaching effects on fabrics washed with the detergent additive compositions
and dried in the presence of visible light and atmospheric oxygen and can also synergistically
enhance the bleaching effect of conventional bleaching agents such as sodium perborate.
The porphine bleach is preferably used in an amount such that the level of porphine
in the composition is in the range from 0.004% to 0.5%, more preferably from 0.001
% to 0.1 %, especially from 0.002% to 0.05% by weight.
[0067] Preferred enzymatic materials include the commercially available amylases, and neutral
and alkaline proteases conventionally incorporated into detergent compositions. Suitable
enzymes are discussed in US Patents 3,519,570 and 3,533,139. Examples of suitable
enzymes include the materials sold under the Registered Trade Marks Maxatase, Rapidase
and Alcalase.
[0068] As stated previously most of the above-mentioned functional ingredients, with the
exception of the nonionic surfactants, the organic suds modifiers and certain anti-redeposition
agents, are solid materials which form the dispersed particulate phase of the detergent
compositions. The particulates are insoluble, or only partly soluble, in the solidified
liquid phase and ideally are finely divided. Their particle size is of no more than
150 µm and preferably should be less than 100 µm, ideally less than 50 pm.
[0069] Preferred detergent compositions useful in the present invention include one or more
of a cationic surfactant as hereinbefore defined, most preferably of the type where
Y is

I and m is 1 or 2, a chelating agent of the amino polyphosphonate type particularly
EDTMP or DETPMP and a peroxyacid bleach precursor of the tetracetyl alkylene diamine
and/or C
l-Cg acyloxybenzene sulphonic or carboxylic acid type, together with a C
8-C
22 ethoxylated primary alcohol and a polyethylene glycol of MWt 4,000-10,000.
[0070] The types and levels of the ingredients of the detergent composition is constrained
by the requirements of mutual unreactivity (if the materials are applied so as to
be in intimate contact), by the weight ratio of components forming particulate solids
to components forming the solidified liquid phase and by the loading limitations of
the substrate. As mentioned above, materials that are capable of mutual reaction can
be incorporated in the additive products of the invention, but must be spatially separated
from each other i.e. by application to a substrate location that is free or substantially
free of the other reactant material(s). The detergent composition is preferably applied,
as described in more detail hereinafter, as a molten dispersion to the substrate so
that the maximum viscosity that can be handled by the application system determines
the maximum level of dispersed particulate solids in the composition. This level is
50% by weight. The minimum level of 5% by weight of the composition is less critical.
Preferably the level of dispersed particulate solids is from 25% to 45% by weight
of the composition.
[0071] Within the limits imposed by the ratio of particulate solid to solidified liquid
components, individual components can be incorporated in amounts up to those corresponding
to component:substrate weight ratios of 10:1. However, for processing and product
aesthetics reasons, the total weight of particulate components per sheet is normally
held to a maximum of 4 times the sheet weight, and individual components are ideally
present at no more than 3 times the sheet weight.
[0072] The detergent compositions useful in the invention also comprise a solidified liquid
phase in which the solid particles are dispersed. As mentioned above certain functional
components of the composition such as nonionic surfactants can act as the, or part
of the, solidified liquid phase but in general the majority of the solidified liquid
phase is a water soluble or water dispersible processing aid having a melting point
in the range from 30°C to 80°C. The most preferred processing aids are organic compounds
having a softening point greater than 40°C and a melting point less than 80°C to permit
their easy processing.
[0073] These compounds serve as an aid in processing and/or in releasing the compostion
from the substrate when the latter is introduced into a wash liquor and, when melted,
provide mixtures having a viscosity of up to 5000 mPa.s at 50°C.
[0074] Typical solids are C
14―C
18 primary and secondary alcohols and C,
27-C
20 fatty acids and ethoxylates thereof containing from 15 to 80 ethylene oxide groups
per mole of alcohol, sorbitan esters of C
12―C
20 fatty acids and polyethylene glycols of Mwt 4000-10,000. Insoluble waxy materials
such as paraffin waxes and alkyl fatty acid esters can also be used in minor amounts
in admixture with one or more water soluble materials. Mixtures of the above water
soluble materials are preferred.
[0075] As indicated above, the organic compounds forming the solidified liquid phase can
serve as a release aid that assists in releasing the compositions from the substrate
upon addition of the product to a wash liquor. In general, materials serving as processing
aids are also suitable as release aids but certain materials, notably C,
6-C
l. fatty acids and polyethylene glycols of MWt 4,000-10,000, are particularly effective
when used in amount such that the weight ratio of compositions: release aid lies in
the range 9:1 to 1:1 particularly 3:1 to 1:1.
[0076] It will be apparent that the detergent compositions of the additive products in accordance
with the invention will incorporate a high level of organic material having a Mpt>
30°C and this will include at least 50% by weight of the composition of carrier material
having a melting point in the range 30°C80°C either in the form of a processing aid
or as one of the functional detergent components. Typically the composition will incorporate
at least 55% of such carrier materials and, depending on the nature and physical characteristics
of the "non-carrier" solid components, the level of carrier materials may be as high
as 70% of the composition.
[0077] The substrate may itself be water soluble or water insoluble and in the latter case
if should preferably possess sufficient structural integrity under the conditions
of the wash to be recovered from the machine at the end of the laundry cycle. Water
soluble materials include certain cellulose ethers, alginates, polyvinyl alcohol and
water soluble polyvinyl pyrrolidone polymers, which can be formed into non-woven and
woven fibrous structures. Suitable water insoluble materials include, but are not
restricted to, natural and synthetic fibres, foams, sponges and films.
[0078] Preferably the sheet is water pervious i.e. water can pass from one surface of the
sheet to the opposite surface and, for film type substrates, perforation of the sheet
is desirable. The most preferred form of the substrate is a sheet of woven or non-woven
fabric or a thin sheet of cellular plastics material. Woven fabric sheets can take
the form of a plain weave natural or synthetic fibre of low fibre count/unit length,
such as is used for surgical dressings, or of the type known as cheese cloth. Loading
limitations on sheet type substrates limit the amount of detergent composition that
can be applied to the sheet namely to a maximum represented by a precursor:sheet weight
ratio of about 10:1.
[0079] A very desirable attribute of the laundry additive products of the present invention
is that they do not interfere with the mechanical operation of the washing machine
into which they are put. A high proportion of domestic washing machines are of the
rotating perforated drum type in which the perforations extend over the entire peripheral
surface. In this type of equipment the drum construction and mode of operation obviates
any problem of obstruction to liquid flow in the machine. Certain older types of machine
utilise an agitator in a stationary vessel provided with a recirculating liquid system.
In order to avoid liquid blockage in this machine type it may be necessary to provide
slits or perforations in the substrate, particularly if it is in sheet form. Sheet
structures of this type are disclosed in McQueary US Patents Nos. 3944694 and 3956556
issued March 16, 1976 and May 11, 1976 respectively.
[0080] As stated above, suitable materials which can be used as a substrate in the invention
herein include, among others, sponges, paper, and woven and non-woven fabrics.
[0081] A suitable sponge like material that can be used in the present invention comprises
an absorbent foam like material in the form of a sheet. The term 'absorbent foam-like
material' is intended to encompass three dimensional absorptive materials such as'gas
blown foams', natural sponges and composite fibrous based structures such as are disclosed
in US Patent Nos. 3311115 and 3430630. A particularly suitable material of this type
is a hydrophilic polyurethane foam in which the internal cellular walls of the foam
have been broken by reticulation. Foams of this type are described in detail in Dulle
US Patent No. 3794029. A preferred example of this foam type comprises a hydrophilic
polyurethane foam of density 0.036 g/cm
3 (0.596 grs per cubic inch) with a cell count of between 8 and 40 cells per cm, preferably
about 24 to 32 per cm available from the Scott Paper Company, Eddystone, Pennsylvania
USA., under the Registered Trade Mark "Hydrofoam". Preferred sheets of this type of
material have thicknesses in the range from 3 to 5 mm.
[0082] A suitable paper-based absorbent structure containing 2 or 3 paper plies is disclosed
in US-A-3414459.
[0083] The preferred substrates of the laundry additive products of the invention are apertured
and non apertured nonwoven fabrics which can generally be defined as adhesively bonded
fibrous or filamentous products, having a web or carded fibre structure (where the
fibre strength is suitable to allow carding) or comprising fibrous mats, in which
the fibres or filaments are distributed haphazardly or in random array (i.e. an array
of fibres in a carded web wherein partial orientation of the fibres is frequently
present as well as a completely haphazard distribution orientation) or substantially
aligned. The fibres or filaments can be natural (e.g. wool, silk, wood pulp, jute,
hemp, cotton, linen, sisal, or ramie), synthetic (e.g. rayon, cellulose, ester, polyvinyl
derivatives, polyolefins, polyamides, or polyesters) or mixtures of any of the above.
[0084] Methods of making non-woven cloths are not a part of this invention and being well
known in the art, are not described in detail herein. Generally, such cloths are made
by air or water laying processes in which the fibres or filaments are first cut to
desired lengths from long strands, passed into a water or air stream, and then deposited
onto a screen through which the fibre-laden air or water is passed. The deposited
fibres or filaments are then adhesively bonded together, dried, cured and otherwise
treated as desired to form the non-woven cloth. Non-woven cloths made of polyesters,
polyamides, vinyl resins, and other thermoplastic fibres can be bonded, i.e. the fibres
are spun out onto a flat surface and bonded (melted) together by heat or by chemical
reactions.
[0085] The absorbent properties desired herein are particularly easy to obtain with non-woven
cloths and are provided merely by building up the thickness of the cloth, i.e. by
super-imposing a plurality of carded webs or mats to a thickness adequate to obtain
the necessary absorbent properties, or by allowing a sufficient thickness of the fibres
to deposit on the screen. Any diameter or denier of the fibre (generally up to about
10 denier, 1 denier being equal to 1,1 dtex) can be used, inasmuch as it is the free
space between each fibre that makes the thickness of the cloth directly related to
the absorbent capacity of the cloth, and which further makes the non-woven cloth especially
suitable for impregnation with a peroxy compound detergent composition by means of
interstitial or capillary action. Thus, any thickness necessary to obtain the required
absorbent capacity can be used.
[0086] The choice of binder-resins used in the manufacture of non-woven cloths can provide
substrates possessing a variety of desirable traits. For example, the absorbent capacity
of the cloth can be increased, decreased, or regulated by respectively useing a hydrophilic
binder-resin, a hydrophobic binder-resin or a mixture thereof in the fibre bonding
step. Moreover, the hydrophobic binder-resin, when used singly or as the predominant
compound of a hydrophobic-hydrophilic mixture, provides non-woven cloths which are
especially useful as substrates when the detergent composition-substrate combinations
disclosed herein are used in an automatic washer.
[0087] When the substrate herein is a bonded non-woven cloth made from fibres, deposited
haphazardly or in random array on the screen, the compositions exhibit excellent strength
in all directions and are not prone to tear or separate when used in the washer.
[0088] Preferably, the non-woven cloth is water-laid or air-laid and is made from cellulosic
fibres, particularly from regenerated cellulose or rayon, which are lubricated with
standard textile lubricant. Preferably the fibres are from 4 to 50 mm in length and
are from 0.16 to 0.55 Tex. Preferably the fibres are at least partially orientated
haphazardly, particularly substantially haphazardly, and are adhesively bonded together
with hydrophobic or substantially hydrophobic binder-resin, particularly with a nonionic
self-crosslinking acrylic polymer or polymers. Conveniently, the cloth comprises 70%
fibre and 30% binder-resin polymer by weight and has a basis weight of from 10 to
100, preferably from 24 to 72 g/m
2.
[0089] A suitable example is an air-laid, non-woven cloth comprising 70% regenerated cellulose
(American Viscose Corporation) and 30% hydrophobic binder-resins (Rhoplex HA-8 on
one side of the cloth, Rhoplex HA-16 on the other; Rhoplex being a Trade Name for
binder resins sold by Rohm & Haas, Inc). The cloth has a thickness of 0.1 to 0.125
mm and a basis weight of 29 g/m
2. A 30 cm length of the cloth 21 cm wide weighs 1.78 grams. The fibers are 10 mm in
length, 0.16 tex, and are orientated substantially haphazardly. The fibres are lubricated
with sodium oleate.
[0090] A further exemplary substrate is a water-laid, non-woven cloth commercially available
from C H Dexter Co., Inc. The fibres are regenerated cellulose, 15 mm in length, 0.16
tex, and are lubricated with a similar standard textile lubricant. The fibres comprise
70% of the non-woven cloth by weight and are orientated substantially haphazardly;
the binder-resin (HA-8) comprises 30% by weight of the cloth. The substrate is 0.1
mm thick, and it has a basis weight of 29 g/m
2. A 30 cm length of the cloth 21 cm wide, weighs 1.66 grams.
[0091] Apertured non-woven substrates are also useful for the purposes of the present invention.
The apertures, which extend between opposite surfaces of the susbtrate are normally
in a pattern and are formed during lay-down of the fibres to produce the substrate.
Exemplary apertured non-woven substrates are disclosed in US Patent Nos. 3,741,724,
3,930,086 and 3,750,237.
[0092] A suitable diamond patterned apertured substrate is obtainable from Chicopee Manufacturing
Co., Milltown, New Jersey, USA under the Code No. SK 650 WFX 577 and comprises a polyester-wood
pulp mixture have a basis weight of 50 g/m
2 and approximately 13 apertures per square cm.
[0093] Another preferred example of an apertured non-woven substrate, also available from
Chicopee Manufacturing Co., under the Code No. AK 30 ML 1379 comprises a regenerated
cellulose sheet of 3.3 dtex fibres bonded with Rhoplex RA 8 binder (fibre:binder ratio
70:30) having a basis weight of 40 g/m
2 and 17 apertures/cm2. A highly preferred square patterned apertured substrate of
similar composition but fibre:binder ratio of 80:20 and basis weight 35 g/m
2 is also available from Chicopee BV Holland.
[0094] In general, apertured fabrics for the purposes of the invention have from 10-20 apertures/cm2,
preferably 12-18 apertures/cm2.
[0095] The size and shape of the substrate sheet is a matter of choice and is determined
principally by factors associated with the convenience of its use. Thus the sheet
should not be so small as to become trapped in the crevices of the machine or the
clothes being washed or so large as to be awkward to package and dispense from the
container in which it is sold. For the purposes of the present invention sheets ranging
in plan area from 130 cm
2 to 1300
CM2 are acceptable, the preferred area lying in the range of from 650 cm
2 to 900
cm2
.
[0096] The invention is illustrated in the following examples in which all parts and percentages
are by weight of the composition unless otherwise specified.
[0097] In the Examples, the abbreviations used have the following designation:

Example 1
The following product was prepared:
[0098]

[0099] The substrate was a square patterned apertured non-woven sheet, of size 23 x 35 cm
and basis weight 2.8 g, formed of 100% unbleached crimped rayon fibres (80% fibre,
20% polyacrylate binder). The product was made by forming a melt of the PEG and A
45E7 at approximately 80°C, dispersing the other components (except the perfume) therein
and applying the resultant slurry to the substrate from an applicator roll with which
the substrate was brought into contact. Additional rolls were used to spread the slurry
before it was cooled to ambient temperature to solidify the composition. Perfume was
then sprayed on to the impregnated substrate to produce the final product.
[0100] No appreciable build up of product was noted on the processing equipment and the
product demonstrated virtual freedom from flaking (i.e. a flaking grade of 9+) when
it was folded. Similar results are obtained if the glycerol is replaced by 0.3 g diethylene
glycol or by 0.3 g 1,2-propane diol.
Examples 2-10
[0101] The following products, in accordance with the invention, are prepared (in parts
by weight):
