[0001] This invention relates to detergent compositions containing a heavy metal ion sequestrant
and an organic peroxyacid bleaching system, wherein a means is provided for delaying
the release to the wash solution of the organic peroxyacid bleach relative to the
release of the heavy metal ion sequestrant.
[0002] The satisfactory removal of bleachable soils/stains such as tea, fruit juice and
coloured vegetable soils from soiled/stained substrates is a particular challenge
to the formulator of a detergent composition for use in a washing method such as a
laundry or machine dishwashing method.
[0003] Traditionally, the removal of such bleachable soils/stains has been enabled by the
use of bleach components such as oxygen bleaches, including hydrogen peroxide and
organic peroxyacids. The organic peroxyacids are often obtained by the in situ perhydrolysis
reaction between hydrogen peroxide and an organic peroxyacid bleach precursor.
[0004] A problem encountered with the use of certain organic peroxyacid bleaches in laundry
washing methods is a tendency for these organic peroxyacid bleaches to affect the
colour stability of the fabrics in the wash. Types of fabric damage can include fading
of coloured dyes on the fabrics or localised areas of "patchy" colour bleaching.
[0005] The detergent formulator thus faces the dual challenge of formulating a product which
maximises bleachable soil/stain removal but minimises the occurrence of any unwelcome
fabric colour stability effects of the bleach.
[0006] The Applicants have found that the occurrence of any unwelcome fabric colour stability
effects arising from the use of organic peroxyacid bleaches in a washing method can
be related to the rate of release of the peroxyacid bleach to the wash solution and
also to the absolute level of peroxyacid present in the wash solution.
[0007] A fast rate of release of the peroxyacid bleach to the wash solution tends to heighten
the probability that unwelcome fabric colour stability effects will be observed, as
does a high absolute level of the bleach in the wash solution.
[0008] Whilst reducing either the rate of release of the peroxyacid bleach, or the absolute
level of the bleach employed in the wash tends to ameliorate this problem, this can
be accompanied by a negative effect on the bleachable stain/soil removal ability.
[0009] The Applicants have now however found that where a composition containing both a
heavy metal ion sequestrant and a peroxyacid bleach source is employed, and wherein
a means is provided for delaying the release to a wash solution of the peroxyacid
bleach relative to the release of the heavy metal ion sequestrant enhanced bleachable
stain/soil removal may be obtained. Additionally, where the composition is used in
a laundry washing method a reduction in the propensity for negative fabric colour
stability effects to be observed is also obtained.
[0010] The Applicants have in addition found that bleachable stain/soil removal benefits
may be obtained when a soiled substrate is pretreated with a solution containing a
heavy metal ion sequestrant, and optionally a water soluble builder, prior to being
washed in a method using a bleach containing detergent product.
[0011] It is therefore an object of the present invention to provide compositions suitable
for use in laundry and machine dishwashing methods having enhanced bleachable stain
removal.
[0012] It is also an object of the present invention to provide compositions for use in
a laundry washing method wherein said compositions show less propensity to cause negative
fabric colour stability effects.
[0013] It is a related object of the present invention to provide a stain/soil pretreatment
method involving pretreating the soiled substrate with a solution containing a heavy
metal ion sequestrant and optionally a water soluble builder, prior to washing with
a bleach-containing detergent product.
Summary of the Invention
[0014] According to one aspect of the present invention there is provided a detergent composition
containing
(a) a heavy metal ion sequestrant; and
(b) an organic peroxyacid bleaching system
wherein a means is provided for delaying the release to a wash solution of said organic
peroxyacid relative to the release of said heavy metal ion sequestrant such that in
the T50 test method herein described the time to achieve a concentration that is 50%
of the ultimate concentration of the heavy metal ion sequestrant is less than 120
seconds and the time to achieve a concentration that is 50% of the ultimate concentration
of the organic peroxyacid is more than 180 seconds.
[0015] According to another aspect of the present invention there is provided a detergent
composition containing
(a) a heavy metal ion sequestrant; and
(b) an organic peroxyacid bleaching system
wherein a means is provided for delaying the release to a wash solution of said organic
peroxyacid relative to the release of said heavy metal ion sequestrant such that in
the T50 test method herein described the time to achieve a concentration that is 50%
of the ultimate concentration of said heavy metal ion sequestrant is at least 100
seconds, preferably at least 120 seconds, more preferably at least 150 seconds less
than the time to achieve a concentration that is 50% of the ultimate concentration
of said organic peroxyacid.
[0016] Said organic peroxyacid bleaching system preferably comprises in combination
(i) a hydrogen peroxide source; and
(ii) an organic peroxyacid bleach precursor compound
[0017] According to a preferred aspect of the present invention said composition additionally
contains
(c) a water soluble builder
wherein a means is provided for delaying the release to a wash solution of the organic
peroxyacid relative to the release of said water soluble builder such that in the
T50 test method herein described the time to achieve a concentration that is 50% of
the ultimate concentration of said water soluble builder is less than 120 seconds
and the time to achieve a concentration that is 50% of the ultimate concentration
of said organic peroxyacid is more than 180 seconds.
[0018] According to another aspect of the present invention there is provided a washing
method comprising the steps of:
(1) applying a bleach-free solution of a composition containing a heavy metal ion
sequestrant to a soiled substrate;
(2) allowing said solution to remain in contact with said soiled substrate for an
effective time interval;
(3) washing said soiled substrate using a washing method involving use of a bleach-containing
detergent composition.
Heavy metal ion sequestrant
[0019] The detergent compositions of the invention contain a heavy metal ion sequestrant.
By heavy metal ion sequestrant it is meant herein components which act to sequester
(chelate) heavy metal ions. These components may also have calcium and magnesium chelation
capacity, but preferentially they show selectivity to binding heavy metal ions such
as iron, manganese and copper.
[0020] 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.
[0021] 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. 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.
[0022] 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.
[0023] 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.
[0024] 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.
[0025] 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. Examples of such preferred sodium salts of EDDS include Na
2EDDS and Na
3EDDS. Examples of such preferred magnesium complexes of EDDS include MgEDDS and Mg
2EDDS.
[0026] Other suitable heavy metal ion sequestrants for use herein are iminodiacetic acid
derivatives such as 2-hydroxyethyl diacetic acid or glyceryl imino diacetic acid,
described in EP-A-317,542 and EP-A-399,133.
[0027] The iminodiacetic acid-N-2-hydroxypropyl sulfonic acid and aspartic acid N-carboxymethyl
N-2-hydroxypropyl-3-sulfonic acid sequestrants described in EP-A-516,102 are also
suitable herein. The β-alanine-N,N'-diacetic acid, aspartic acid-N,N'-diacetic acid,
aspartic acid-N-monoacetic acid and iminodisuccinic acid sequestrants described in
EP-A-509,382 are also suitable.
[0028] EP-A-476,257 describes suitable amino based sequestrants. EP-A-510,331 describes
suitable sequestrants derived from collagen, keratin or casein. EP-A-528,859 describes
a suitable alkyl iminodiacetic acid sequestrant. Dipicolinic acid and 2-phosphonobutane-1,2,4-tricarboxylic
acid are alos suitable. Glycinamide-N,N'-disuccinic acid (GADS) is also suitable.
Organic peroxyacid bleaching system
[0029] An essential feature of the invention is an organic peroxyacid bleaching system.
In one preferred execution the bleaching system 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 execution 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
[0030] Inorganic perhydrate salts are a preferred source of hydrogen peroxide. These salts
are normally incorporated in the form of the alkali metal, preferably 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.
[0031] Examples of suitable inorganic perhydrate salts include perborate, percarbonate,
perphosphate, persulfate and persilicate salts and any mixtures thereof. 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.
[0032] 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.
[0033] Alkali metal percarbonates, particularly sodium percarbonate are preferred perhydrates
for inclusion in compositions in accordance with the invention. Compositions containing
percarbonate, have been found to have a reduced tendency to form undesirable gels
in the presence of surfactants and water than similar compositions which contain perborate.
It is believed that this is because typically percarbonate has a lower surface area
and lower porosity than perborate monohydrate. This low surface area and low porosity
acts to prevent the co-gelling with fine particles of surfactant agglomerates and
is therefore not detrimental to dispensing.
[0034] 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. The percarbonate is most preferably
incorporated into such compositions in a coated form which provides in product stability.
[0035] 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.
[0036] Other coatings which contain silicate (alone or with borate salts or boric acids
or other inorganics), waxes, oils, fatty soaps can also be used advantageously within
the present invention.
[0037] Potassium peroxymonopersulfate is another inorganic perhydrate salt of use in the
detergent compositions herein.
Peroxyacid bleach precursor
[0038] 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 perhydroloysis
the structure of the peroxyacid produced is

[0039] Peroxyacid bleach precursor compounds are preferably incorporated at a level of from
0.5% to 20% by weight, more preferably from 1% to 15% by weight, most preferably from
1.5% to 10% by weight of the detergent compositions.
[0040] 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.
[0041] The Applicants have found that 'patchy' damage can be particularly associated with
peroxyacid bleach precursor compounds which on perhydrolysis provides a peroxyacid
which is
(i) a perbenzoic acid, or non-cationic substituted derivative thereof; or
(ii) a cationic peroxyacid.
[0042] Benzoxazin precursors have also been found to be particularly susceptible to the
problem.
Leaving groups
[0043] 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 stabilize for use in a bleaching
composition.
[0044] Preferred L groups are selected from the group consisting of:

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, 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 ammmonium groups
[0045] 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, and derivatives thereof precursors
[0046] Perbenzoic acid precursor compounds provide perbenzoic acid on perhydrolysis.
[0047] Suitable O-acylated perbenzoic acid precursor compounds include the substituted and
unsubstituted benzoyl oxybenzene sulfonates, including for example benzoyl oxybenzene
sulfonate:

[0048] Also suitable are the benzoylation products of sorbitol, glucose, and all saccharides
with benzoylating agents, including for example;

[0049] 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.
[0050] Other perbenzoic acid precursors include the benzoyl diacyl peroxides, the benzoyl
tetraacyl peroxides, and the compound having the formula:

[0051] Phthalic anhydride is another suitable perbenzoic acid precursor compound herein:

[0052] 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 an aryl, alkoxyaryl or alkaryl group containing from 1 to 12 carbon atoms, or
a substituted phenyl group containing from 6 to 18 carbon atoms, preferably a benzoyl
group.
Perbenzoic acid derivative precursors
[0053] Perbenzoic acid derivative precursors provide substituted perbenzoic acids on perhydrolysis.
[0054] 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 (ie; non-cationic) functional group including, for example
alkyl, hydroxy, alkoxy, halogen, amine, nitrosyl and amide groups.
[0055] 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
[0056] Cationic peroxyacid precursor compounds produce cationic peroxyacids on perhydrolysis.
[0057] 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 ammmonium group, preferably an ethyl or methyl
ammonium group. Cationic peroxyacid precursors are typically present in the solid
detergent compositions as a salt with a suitable anion, such as a halide ion.
[0058] 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
[0059] 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.
[0060] Examples of preferred cationic peroxyacid precursors are described in UK Patent Application
No. 9407944.9 and US Patent Application Nos. 08/298903, 08/298650, 08/298904 and 08/298906.
[0061] 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.
[0062] A preferred cationically substituted benzoyl oxybenzene sulfonate is the 4-(trimethyl
ammonium) methyl derivative of benzoyl oxybenzene sulfonate:

[0063] A preferred cationically substituted alkyl oxybenzene sulfonate has the formula:

[0064] Preferred cationic peroxyacid precursors of the N-acylated caprolactam class include
the trialkyl ammonium methylene benzoyl caprolactams, particularly trimethyl ammonium
methylene benzoyl caprolactam:

[0065] 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.
[0066] Another preferred cationic peroxyacid precursor is 2-(N,N,N-trimethyl ammonium) ethyl
sodium 4-sulphophenyl carbonate chloride.
Alkyl percarboxylic acid bleach precursors
[0067] Alkyl percarboxylic acid bleach precursors form percarboxylic acids on perhydrolysis.
Preferred precursors of this type provide peracetic acid on perhydrolysis.
[0068] 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. Tetraacetylethylenediamine (TAED) is particularly preferred.
[0069] 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 pentaacetyl glucose.
Amide substituted alkyl peroxyacid precursors
[0070] 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
[0071] 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.
[0072] An especially preferred precursor of the benzoxazin-type is:

Preformed organic peroxyacid
[0073] 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 1% to 15 % by weight, more preferably from 1% to 10%
by weight of the composition.
[0074] A preferred class of organic peroxyacid compounds are the amide substituted compounds
of the following general formulae:

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 1 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.
[0075] Other organic peroxyacids include diacyl and tetraacylperoxides, especially diperoxydodecanedioc
acid, diperoxytetradecanedioc acid and diperoxyhexadecanedioc acid. Mono- and diperazelaic
acid, mono- and diperbrassylic acid and N-phthaloylaminoperoxicaproic acid are also
suitable herein.
Chlorine bleach
[0076] The compositions herein are preferably free of chlorine bleach.
Bleach catalyst
[0077] The invention also encompasses compositions containing a catalytically effective
amount of a bleach catalyst such as a water-soluble manganese salt.
[0078] The bleach catalyst is used in a catalytically effective amount in the compositions
herein. By "catalytically effective amount" is meant an amount which is sufficient,
under whatever comparative test conditions are employed, to enhance bleaching and
removal of the stain or stains of interest from the target substrate. Thus, in a fabric
laundering operation, the target substrate will typically be a fabric stained with,
for example, various food stains. For automatic dishwashing, the target substrate
may be, for example, a porcelain cup or plate with tea stain or a polyethylene plate
stained with tomato soup. The test conditions will vary, depending on the type of
washing appliance used and the habits of the user. Thus, front-loading laundry washing
machines of the type employed in Europe generally use less water and higher detergent
concentrations than do top-loading U.S.-style machines. Some machines have considerably
longer wash cycles than others. Some users elect to use very hot water; others use
warm or even cold water in fabric laundering operations.
[0079] Of course, the catalytic performance of the bleach catalyst will be affected by such
considerations, and the levels of bleach catalyst used in fully-formulated detergent
and bleach compositions can be appropriately adjusted. As a practical matter, and
not by way of limitation, the compositions and processes herein can be adjusted to
provide on the order of at least one part per ten million of the active bleach catalyst
species in the aqueous washing liquor, and will preferably provide from about 1 ppm
to about 200 ppm of the catalyst species in the laundry liquor. To illustrate this
point further, on the order of 3 micromolar manganese catalyst is effective at 40°C,
pH 10 under European conditions using perborate and a bleach precursor (e.g., benzoyl
caprolactam). An increase in concentration of 3-5 fold may be required under U.S.
conditions to achieve the same results. Conversely, use of a bleach precusor and the
manganese catalyst with perborate may allow the formulator to achieve equivalent bleaching
at lower perborate usage levels than products without the manganese catalyst.
[0080] The bleach catalyst material herein can comprise the free acid or be in the form
of any suitable salts.
[0081] One type of bleach catalyst is a catalyst system comprising a heavy metal cation
of defined bleach catalytic activity, such as copper, iron or manganese cations, an
auxiliary metal cation having little or no bleach catalytic activity, such as zinc
or aluminum cations, and a sequestrant having defined stability constants for the
catalytic and auxiliary metal cations, particularly ethylenediaminetetraacetic acid,
ethylenediaminetetra(methylenephosphouic acid) and water-soluble salts thereof. Such
catalysts are disclosed in U.S. Pat. 4,430,243.
[0082] Other 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-triazacyclodadecane,
2-methyl-1,4,7-triazacyclononane, 2-methyl-1,4,7-triazacyclononane, 1,2,4,7-tetramethyl-1,4,7-triazacyclononane,
and mixtures thereof.
[0083] 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-trimethyl-1,4,7-triazacyclononane)(OCH
3)
3-(PF
6). Still another type of bleach catalyst, as disclosed in U.S. Pat. 5,114,606, is
a water-soluble complex of manganese (II), (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.
[0084] 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, pyrazine, 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'-bispyridylamine.
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.
[0085] Other examples include Mn gluconate, Mn(CF
3SO
3)
2, Co(NH
3)
5Cl, and the binuclear Mn complexed 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.
[0086] The bleach catalysts may also be prepared by combining a water-soluble ligand with
a water-soluble manganese salt in aqueous media and concentrating the resulting mixture
by evaporation. Any convenient water-soluble salt of manganese can be used herein.
Manganese (II), (III), (IV) and/or (V) is readily available on a commercial scale.
In some instances, sufficient manganese may be present in the wash liquor, but, in
general, it is preferred to add Mn cations in the compositions to ensure its presence
in catalytically-effective amounts. Thus, the sodium salt of the ligand and a member
selected from the group consisting of MnSO
4, Mn(ClO
4)
2 or MnCl
2 (least preferred) are dissolved in water at molar ratios of ligand:Mn salt in the
range of about 1:4 to 4:1 at neutral or slightly alkaline pH. The water may first
be de-oxygenated by boiling and cooled by sparging with nitrogen. The resulting solution
is evaporated (under N
2, if desired) and the resulting solids are used in the bleaching and detergent compositions
herein without further purification.
[0087] In an alternate mode, a water-soluble manganese source, such as MnSO
4, is added to the bleach/cleaning composition or to the aqueous bleaching/cleaning
bath which comprises the ligand. Some tyge of complex is appanently formed
in situ, and improved bleach performance is secured. In such an
in situ process, it is convenient to use a considerable molar excess of the ligand over the
manganese, and mole ratios of ligand:Mn typically are 3:1 to 15:1. The additional
ligand also serves to scavenge vagrant metal ions such as iron and copper, thereby
protecting the bleach from decomposition. One possible such system is described in
European patent application, publication no. 549,271.
[0088] While the structures of some of the bleach-catalyzing manganesecomplexes described
herein 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 Mnligand species which
actually exists, it functions in an apparently catalytic manner to provide improved
bleaching performances on stubborn stains such as tea, ketchup, coffee, blood, and
the like.
[0089] 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).
Relative release kinetics
[0090] In an essential aspect of the invention a means is provided for delaying the release
to a wash solution of the organic peroxyacid bleach relative to the release of the
heavy metal ion sequestrant.
[0091] Said means may comprise a means for delaying the release of the organic peroxyacid
bleach to the wash solution.
[0092] Alternatively said means may comprise a means for enhancing the rate of release of
the heavy metal ion sequestrant to the solution.
Delayed rate of release - means
[0093] The means provides for delayed release of an organic peroxyacid bleach source itself
to the wash solution or where the peroxyacid source is an organic peroxyacid precursor
compound the delayed release means may comprise a means of inhibiting, or preventing
the in situ perhydrolysis reaction which releases the organic peroxyacid into the
solution. Such means could, for example, include delaying release of the hydrogen
peroxide source to the wash solution, by for example, delaying release of any inorganic
perhydrate salt, acting as a hydrogen peroxide source, to the wash solution.
[0094] The delayed release means can includes coating any suitable component with a coating
or mixture of coatings designed to provide the delayed 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.
[0095] 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.
[0096] 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.
[0097] Other suitable coating materials can comprise the alkali and alkaline earth metal
sulphates, silicates and carbonates, including calcium carbonate.
[0098] Preferred coating material is sodium silicate of SiO
2 : Na
2O ratio from 1.6 : 1 to 3.4 : 1, preferably 2.8 : 1, applied as an aqueous solution
to give a level of from 2% to 10%, (normally from 3% to 5%) of silicate solids by
weight of the percarbonate. Magnesium silicate can also be included in the coating.
[0099] 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.
[0100] 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 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.
[0101] Cellulose derivatives such as methylcellulose, carboxymethylcellulose, ethyl hydroxyethylcellulose
and hydroxyethylcellulose, and homo- or co-polymeric polycarboxylic acids or their
salts are other examples of binders suitable for use herein.
[0102] 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 limted 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.
[0103] Other means of providing the required delayed release include mechanical means for
altering the physical characteristics of the bleach to control its solubility and
rate of release. Suitable protocols could include compaction, mechanical injection,
manual injection, and adjustment of the solubility of the bleach compound by selection
of particle size of any particulate component.
[0104] Whilst the choice of particle size will depend both on the composition of the particulate
component, and the desire to meet the desired delayed 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.
[0105] Additional protocols for providing the means of delayed 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 delayed release kinetics to be achieved.
Enhanced rate of release - means
[0106] All suitable means for enhancing the rate of release of the heavy metal ion sequestrant
to the solution are envisaged.
[0107] The enhanced release means can include coating any suitable component with a coating
designed to provide the enhanced release. The coating may therefore, for example,
comprise a highly, or even effervescently, water soluble material.
[0108] Other means of providing the required delayed release include mechanical means for
altering the physical characteristics of the heavy metal ion sequestrant to enhance
its solubility and rate of release.
[0109] A suitable protocol could include deliberate selection of the particle size of any
heavy metal ion sequestrant containing component. The choice of particle size will
depend both on the composition of the particulate component, and the desire to meet
the desired enhanced release kinetics. It is desirable that the particle size should
be less than 1200 micrometers, preferably having an average particle diameter of from
1100 to 500 micrometers.
[0110] Additional protocols for providing the means of delayed release include the suitable
choice of any other components of the detergent composition matrix, or of any particulate
component containing the heavy metal ion sequestrant, such that when the composition
is introduced to the wash solution the ionic strength environment therein provided
enables the required enhanced release kinetics to be achieved.
Relative rate of release - kinetic parameters
[0111] The release of the organic peroxyacid bleach component from the peroxyacid bleaching
system relative to that of the heavy metal ion sequestrant component is such that
in the T50 test method herein described the difference between the time to achieve
a concentration that is 50% of the ultimate concentration of said heavy metal ion
sequestrant is less than 120 seconds, preferably less than 90 seconds, more preferably
less than 60 seconds, and the time to achieve a concentration that is 50% of the ultimate
concentration of said organic peroxyacid bleach is more than 180 seconds, preferably
from 180 to 480 seconds, more preferably from 240 to 360 seconds.
[0112] In a highly preferred aspect of the invention the release of bleach is such that
in the T50 test method herein described the time to achieve a level of total available
oxygen (AvO) that is 50% of the ultimate level is more than 180 seconds, preferably
from 180 to 480 seconds, more preferably from 240 to 360 seconds. A method for determining
AvO levels is disclosed in European Patent Application No. 93870004.4.
[0113] In another preferred aspect of the invention, where the peroxyacid bleach source
is a peroxyacid bleach precursor, employed in combination with a hydrogen peroxide
source the kinetics of release to the wash solution of the hydrogen peroxide relative
to those of the heavy metal ion sequestrant component is such that in the T50 test
method herein described the time to achieve a concentration that is 50% of the ultimate
concentration of said heavy metal ion sequestrant is less than 120 seconds. preferably
less than 90 seconds, more preferably less than 60 seconds, and the time to achieve
a concentration that is 50% of the ultimate concentration of said hydrogen peroxide
is more that 180 seconds, preferably from 180 to 480 seconds. more preferably from
240 to 360 seconds.
[0114] The ultimate wash concentration of the heavy metal ion sequestrant is typically from
0.0001% to 0.05 % by weight, but preferably is more than 0.001%, more preferably more
than 0.002%.
[0115] The ultimate wash concentration of any inorganic perhydrate bleach is typically from
0.005% to 0.25% by weight, but preferably is more than 0.05%, more preferably more
than 0.075%.
[0116] The ultimate wash concentration of any peroxyacid precursor is typically 0.001% to
0.08% by weight, but preferably is from 0.005% to 0.05%, most preferably from 0.015%
to 0.05%.
Delayed release - test method
[0117] The delayed release kinetics herein are defined with respect to a 'TA test method'
which measures the time to achieve A % of the ultimate concentration/level of that
component when a composition containing the component is dissolved according to the
standard conditions now set out.
[0118] The standard conditions involve a 1 litre glass beaker filled with 1000 ml of distilled
water at 20°C, to which 10g of composition is added. The contents of the beaker are
agitated using a magnetic stirrer set at 100 rpm. The magnetic stirrer is pea/ovule-shaped
having a maximum dimension of 1.5cm, and a minimum dimension of 0.5cm. The ultimate
concentration/level is taken to be the concentration/level attained 10 minutes after
addition of the composition to the water-filled beaker.
[0119] Suitable analytical methods are chosen to enable a reliable determination of the
incidental, and ultimate in solution concentrations of the component of concern. subsequent
to the addition of the composition to the water in the beaker.
[0120] Such analytical methods can include those involving a continuous monitoring of the
level of concentration of the component, including for example photometric and conductimetric
methods.
[0121] Alternatively, methods involving removing titres from the solution at set time intervals,
stopping the disssolution process by an appropriate means such as by rapidly reducing
the temperature of the titre, and then determining the concentration of the component
in the titre by any means such as chemical titrimetric methods, can be employed.
[0122] Suitable graphical methods, including curve fitting methods, can be employed, where
appropriate, to enable calculation of the the TA value from raw analytical results.
[0123] The particular analytical method selected for determining the concentration of the
component, will depend on the nature of that component, and of the nature of the composition
containing that component.
Water-soluble builder compound
[0124] The detergent compositions of the present invention may contain as a highly preferred
component a water-soluble 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.
[0125] In a highly preferred aspect of the invention a means is also provided for delaying
the release to a wash solution of the bleach relative to the release of the preferred
water soluble builder component. Said means can comprise equivalents of any of the
delayed release means herein described for achieving the delayed release of the bleach
components, described hereinbefore.
[0126] Said delayed release means is preferably chosen such that in the test method herein
described the time to achieve a concentration that is 50% of the ultimate concentration
of said water soluble builder is less than 120 seconds, preferably less than 90 seconds,
more preferably less than 60 seconds.
[0127] The ultimate wash concentration of the water-soluble builder is typically from 0.005%
to 0.4%, preferably from 0.05% to 0.35%, more preferably from 0.1% to 0.3%.
[0128] 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,
silicates and mixtures of any of the foregoing.
[0129] The carboxylate or polycarboxylate builder can be monomeric or oligomeric in type
although monomeric polycarboxylates are generally preferred for reasons of cost and
performance.
[0130] 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.
[0131] Polycarboxylates containing four carboxy groups include oxydisuccinates disclosed
in British Patent No. 1,261,829, 1,1,2,2-ethane tetracarboxylates, 1,1,3,3-propane
tetracarboxylates and 1,1,2,3-propane tetracarboxylates. Polycarboxylates in 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.
[0132] 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.
[0133] Of the above, the preferred polycarboxylates are hydroxycarboxylates containing up
to three carboxy groups per molecule, more particularly citrates.
[0134] 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.
[0135] 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 about 50°C, especially less than about
40°C.
[0136] 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.
[0137] 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 about 6 to 21, and salts of phytic acid.
[0138] Suitable silicates include the water soluble sodium silicates with an SiO
2: Na
2O ratio of from 1.0 to 2.8, with ratios of from 1.6 to 2.4 being preferred, and 2.0
ratio being most preferred. The silicates may be in the form of either the anhydrous
salt or a hydrated salt. Sodium silicate with an SiO
2: Na
2O ratio of 2.0 is the most preferred silicate.
[0139] Silicates are preferably present in the detergent compositions in accord with the
invention at a level of from 5% to 50% by weight of the composition, more preferably
from 10% to 40% by weight.
Additional detergent components
[0140] The detergent compositions of the invention may also contain additional detergent
components. The precise nature of these additional components, and levels of incorporation
thereof will depend on the physical form of the composition, and the nature of the
cleaning operation for which it is to be used.
[0141] The compositions of the invention may for example, be formulated as hand and machine
laundry detergent compositions, including laundry additive compositions and compositions
suitable for use in the pretreatment of stained fabrics and machine dishwashing compositions.
[0142] When formulated as compositions suitable for use in a machine washing method, eg:
machine laundry and machine dishwashing methods, the compositions of the invention
preferably contain one or more additional detergent components selected from surfactants,
water-insoluble builders, organic polymeric compounds, additional enzymes, suds suppressors,
lime soap dispersants, soil suspension and anti-redeposition agents and corrosion
inhibitors. Laundry compositions can also contain, as additional detergent components,
softening agents.
Surfactant
[0143] The detergent compositions of the invention may contain as an additional detergent
component a surfactant selected from anionic, cationic, nonionic ampholytic, amphoteric
and zwitterionic surfactants and mixtures thereof.
[0144] The surfactant is typically present at a level of from 0.1% to 60% by weight. More
preferred levels of incorporation of surfactant are from 1% to 35% by weight, most
preferably from 1% to 20% by weight.
[0145] The surfactant is preferably formulated to be compatible with any enzyme components
present in the composition. In liquid or gel compositions the surfactant is most preferably
formulated such that it promotes, or at least does not degrade, the stability of any
enzyme in these compositions.
[0146] 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. Further examples are given in "Surface Active Agents
and Detergents" (Vol. I and II by Schwartz, Perry and Berch). A list of suitable cationic
surfactants is given in U.S.P. 4,259,217 issued to Murphy on March 31, 1981.
[0147] Where present, ampholytic, amphoteric and zwitteronic surfactants are generally used
in combination with one or more anionic and/or nonionic surfactants.
Anionic surfactant
[0148] Essentially any anionic surfactants useful for detersive purposes can be included
in the compositions. 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.
[0149] 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
[0150] Anionic sulfate surfactants suitable for use herein include the linear and branched
primary alkyl sulfates, alkyl ethoxysulfates, fatty oleyl 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).
[0151] Alkyl ethoxysulfate surfactants are preferably selected from the group consisting
of the C
6-C
18 alkyl sulfates which have been ethoxylated with from about 0.5 to about 20 moles
of ethylene oxide per molecule. More preferably, the alkyl ethoxysulfate surfactant
is a C
6-C
18 alkyl sulfate which has been ethoxylated with from about 0.5 to about 20, preferably
from about 0.5 to about 5, moles of ethylene oxide per molecule.
Anionic sulfonate surfactant
[0152] 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
[0153] Anionic carboxylate surfactants suitable for use herein include the alkyl ethoxy
carboxylates, the alkyl polyethoxy polycarboxylate surfactants and the soaps ('alkyl
carboxyls'), especially certain secondary soaps as described herein.
[0154] Preferred alkyl ethoxy carboxylates for use herein include those with the formula
RO(CH
2CH
20)
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 about 20 %, and
the amount of material where x is greater than 7, is less than about 25%, the average
x is from about 2 to 4 when the average R is C
13 or less, and the average x is from about 3 to 10 when the average R is greater than
C
13, and M is a cation, preferably chosen from alkali metal, alkaline earth metal, ammonium,
mono-, di-, and tri-ethanol-ammonium, most preferably from sodium, potassium, ammonium
and mixtures thereof with magnesium ions. The preferred alkyl ethoxy carboxylates
are those where R is a C
12 to C
18 alkyl group.
[0155] Alkyl polyethoxy polycarboxylate surfactants suitable for use herein 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, wherein at least
one R
1 or R
2 is a succinic acid radical or hydroxysuccinic acid radical. 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.
Anionic secondary soap surfactant
[0156] Preferred soap surfactants are secondary snap surfactants which contain a carboxyl
unit connected to a secondary carbon. The secondary carbon can be in a ring structure,
e.g. as in p-octyl benzoic acid, or as in alkyl-substituted cyclohexyl carboxylates.
The secondary soap surfactants should preferably contain no ether linkages, no ester
linkages and no hydroxyl groups. There should preferably be no nitrogen atoms in the
head-group (amphiphilic portion). The secondary soap surfactants usually contain 11-15
total carbon atoms, although slightly more (e.g., up to 16) can be tolerated, e.g.
p-octyl benzoic acid.
[0157] The following general structures further illustrate some of the preferred secondary
soap surfactants:
A. A highly preferred class of secondary soaps comprises the secondary carboxyl materials
of the formula R3 CH(R4)COOM, wherein R3 is CH3(CH2)x and R4 is CH3(CH2)y, wherein y can be O or an integer from 1 to 4, x is an integer from 4 to 10 and
the sum of (x + y) is 6-10, preferably 7-9, most preferably 8.
B. Another preferred class of secondary soaps comprises those carboxyl compounds wherein
the carboxyl substituent is on a ring hydrocarbyl unit, i.e., secondary soaps of the
formula R5-R6-COOM, wherein R5 is C7-C10, preferably C8-C9, alkyl or alkenyl and R6 is a ring structure, such as benzene, cyclopentane and cyclohexane. (Note: R5 can be in the ortho, meta or para position relative to the carboxyl on the ring.)
C. Still another preferred class of secondary soaps comprises secondary carboxyl compounds
of the formula
CH3(CHR)k-(CH2)m-(CHR)n-CH(COOM)(CHR)o-(CH2)p-(CHR)q-CH3,
wherein each R is C
1-C
4 alkyl, wherein k, n, o, q are integers in the range of 0-8, provided that the total
number of carbon atoms (including the carboxylate) is in the range of 10 to 18.
[0158] In each of the above formulas A, B and C, the species M can be any suitable. especially
water-solubilizing, counterion.
[0159] Especially 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.
Alkali metal sarcosinate surfactant
[0160] 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
oleyl methyl sarcosinates in the form of their sodium salts.
Nonionic surfactant
[0161] Essentially any anionic surfactants useful for detersive purposes can be included
in the compositions. Exemplary, non-limiting classes of useful nonionic surfactants
are listed below.
Nonionic polyhydroxy fatty acid amide surfactant
[0162] Polyhydroxy fatty acid amides suitable for use herein are those having the structural
formula R
2CONR
1Z wherein : R1 is H, C
1-C
4 hydrocarbyl, 2-hydroxy ethyl, 2-hydroxy propyl, or a mixture thereof, preferable
C1-C4 alkyl, more preferably C
1 or C
2 alkyl, most preferably C
1 alkyl (i.e., methyl); and R
2 is a C
5-C
31 hydrocarbyl, preferably straight-chain C
5-C
19 alkyl or alkenyl, more preferably straight-chain C
9-C
17 alkyl or alkenyl, most preferably straight-chain C
11-C
17 alkyl or alkenyl, or mixture thereof; and Z is a polyhydroxyhydrocarbyl having a
linear hydrocarbyl chain with at least 3 hydroxyls directly connected to the chain,
or an alkoxylated derivative (preferably ethoxylated or propoxylated) thereof. Z preferably
will be derived from a reducing sugar in a reductive amination reaction: more preferably
Z is a glycityl.
Nonionic condensates of alkyl phenols
[0163] The polyethylene, polypropylene, and polybutylene oxide condensates of alkyl phenols
are suitable for use herein. In general, the polyethylene oxide condensates are preferred.
These compounds include the condensation products of alkyl phenols having an alkyl
group containing from about 6 to about 18 carbon atoms in either a straight chain
or branched chain configuration with the alkylene oxide.
Nonionic ethoxylated alcohol surfactant
[0164] The alkyl ethoxylate condensation products of aliphatic alcohols with from about
1 to about 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 about 2 to about 10 moles of ethylene oxide per mole of alcohol.
Nonionic ethoxylated/propoxylated fatty alcohol surfactant
[0165] 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
[0166] 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
about 1500 to about 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
[0167] 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 about 2500 to about
3000. Examples of this type of nonionic surfactant include certain of the commercially
available Tetronic™ compounds, marketed by BASF.
Nonionic alkylpolysaccharide surfactant
[0168] Suitable alkylpolysaccharides for use herein are disclosed in U.S. Patent 4,565,647,
Llenado, issued January 21, 1986, having a hydrophobic group containing from about
6 to about 30 carbon atoms, preferably from about 10 to about 16 carbon atoms and
a polysaccharide, e.g., a polyglycoside, hydrophilic group containing from about 1.3
to about 10, preferably from about 1.3 to about 3, most preferably from about 1.3
to about 2.7 saccharide units. Any reducing saccharide containing 5 or 6 carbon atoms
can be used, e.g., glucose, galactose and galactosyl moieties can be substituted for
the glucosyl moieties. (Optionally the hydrophobic group is attached at the 2-, 3-,
4-, etc. positions thus giving a glucose or galactose as opposed to a glucoside or
galactoside.) The intersaccharide bonds can be, e.g., between the one position of
the additional saccharide units and the 2-, 3-, 4-, and/or 6- positions on the preceding
saccharide units.
[0169] The preferred alkylpolyglycosides have the formula
R
2O(C
nH
2nO)t(glycosyl)
x
wherein R2 is selected from the group consisting of alkyl, alkylphenyl, hydroxyalkyl,
hydroxyalkylphenyl, and mixtures thereof in which the alkyl groups contain from 10
to 18, preferably from 12 to 14, carbon atoms; n is 2 or 3; t is from 0 to 10, preferably
0, and X is from 1.3 to 8, preferably from 1.3 to 3, most preferably from 1.3 to 2.7.
The glycosyl is preferably derived from glucose.
Nonionic fatty acid amide surfactant
[0170] Fatty acid amide surfactants suitable for use herein are those having the formula:
R
6CON(R
7)
2
wherein R
6 is an alkyl group containing from 7 to 21, preferably from 9 to 17 carbon atoms and
each R
7 is selected from the group consisting of hydrogen, C
1-C
4 alkyl, C
1-C
4 hydroxyalkyl, and -(C
2H
4O)
xH, where x is in the range of from 1 to 3.
Amphoteric surfactant
[0171] Suitable amphoteric surfactants for use herein include the amine oxide surfactants
and the alkyl amphocarboxylic acids.
[0172] A suitable example of an alkyl aphodicarboxylic acid for use herein is Miranol(TM)
C2M Conc. manufactured by Miranol, Inc., Dayton, NJ.
Amine Oxide surfactant
[0173] Amine oxides useful herein 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, preferably 8 to 18 carbon
atoms; R
4 is an alkylene or hydroxyalkylene group containing from 2 to 3 carbon atoms, preferably
2 carbon atoms, or mixtures thereof; x is from 0 to 5, preferably from 0 to 3; and
each R
5 is an alkyl or hydyroxyalkyl group containing from 1 to 3, preferably from 1 to 2
carbon atoms, or a polyethylene oxide group containing from 1 to 3, preferable 1,
ethylene oxide groups. The R
5 groups can be attached to each other, e.g., through an oxygen or nitrogen atom, to
form a ring structure.
[0174] These amine oxide surfactants in particular include C
10-C
18 alkyl dimethyl amine oxides and C
8-C
18 alkoxy ethyl dihydroxyethyl amine oxides. Examples of such materials include dimethyloctylamine
oxide, diethyldecylamine oxide, bis-(2-hydroxyethyl)dodecylamine oxide, dimethyldodecylamine
oxide, dipropyltetradecylamine oxide, methylethylhexadecylamine oxide, dodecylamidopropyl
dimethylamine oxide, cetyl dimethylamine oxide, stearyl dimethylamine oxide, tallow
dimethylamine oxide and dimethyl-2-hydroxyoctadecylamine oxide. Preferred are C
10-C
18 alkyl dimethylamine oxide. and C
10-18 acylamido alkyl dimethylamine oxide.
Zwitterionic surfactant
[0175] 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.
Betaine surfactant
[0176] The betaines useful herein are those compounds having the formula
R(R')
2N
+R
2COO
-
wherein R is a C
6-C
18 hydrocarbyl group, preferably a C
10-C
16 alkyl group or C
10-16 acylamido alkyl group, each R
1 is typically C
1-C
3 alkyl, preferably methyl,m and R
2 is a C
1-C
5 hydrocarbyl group, preferably a C
1-C
3 alkylene group, more preferably a C
1-C
2 alkylene group. Examples of suitable betaines include coconut acylamidopropyldimethyl
betaine; hexadecyl dimethyl betaine; C
12-14 acylamidopropylbetaine; C
8-14 acylamidohexyldiethyl betaine; 4[C
14-16 acylmethylamidodiethylammonio]-1-carboxybutane; C
16-18 acylamidodimethylbetaine; C
12-16 acylamidopentanediethyl-betaine; [C
12-16 acylmethylamidodimethylbetaine. 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.
Sultaine surfactant
[0177] The sultaines useful herein are those compounds having the formula
(R(R
1)
2N
+R
2SO
3-
wherein R is a C
6-C
18 hydrocarbyl group, preferably a C
10-C
16 alkyl group, more preferably a C
12-C
13 alkyl group, each R
1 is typically C
1-C
3 alkyl, preferably methyl, and R
2 is a C
1-C
6 hydrocarbyl group, preferably a C
1-C
3 alkylene or, preferably, hydroxyalkylene group.
Ampholytic surfactant
[0178] Ampholytic surfactants can be incorporated into the detergent compositions herein.
These surfactants can be broadly described as aliphatic derivatives of secondary or
tertiary amines, or aliphatic derivatives of heterocyclic secondary and tertiary amines
in which the aliphatic radical can be straight chain or branched.
Cationic surfactants
[0179] Cationic surfactants can also be used in the detergent compositions herein. 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.
Partially soluble or insoluble builder compound
[0180] The detergent compositions of the present invention may contain a partially soluble
or insoluble 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% weight of the
composition.
[0181] Examples of partially water soluble builders include the crystalline layered silicates.
Examples of largely water insoluble builders include the sodium aluminosilicates.
[0182] Crystalline layered sodium silicates have the general formula
NaMSi
x0
2x+1.yH
20
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 are disclosed in EP-A-0164514
and methods for their preparation 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. The most preferred material is δ-Na
2Si
2O
5, available from Hoechst AG as NaSKS-6.
[0183] 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. The solid, water-soluble ionisable material is selected from organic
acids, organic and inorganic acid salts and mixtures thereof.
[0184] Suitable aluminosilicate zeolites have 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.
[0185] The aluminosilicate ion exchange materials 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, Zeoilte MAP, Zeolite HS and mixtures thereof. 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.
Enzyme
[0186] Another optional ingredient useful in the detergent compositions is one or more additional
enzymes.
[0187] Preferred additional enzymatic materials include the commercially available lipases,
amylases, neutral and alkaline proteases, esterases, cellulases, pectinases, lactases
and peroxidases conventionally incorporated into detergent compositions. Suitable
enzymes are discussed in US Patents 3,519,570 and 3,533,139.
[0188] Preferred commercially available protease enzymes include those sold under the tradenames
Alcalase, Savinase, Primase, Durazym, and Esperase by Novo Industries A/S (Denmark),
those sold under the tradename Maxatase, Maxacal and Maxapem by Gist-Brocades, those
sold by Genencor International, and those sold under the tradename Opticlean and Optimase
by Solvay Enzymes. Protease enzyme may be incorporated into the compositions in accordance
with the invention at a level of from 0.0001% to 4% active enzyme by weight of the
composition.
[0189] Preferred amylases include, for example, α-amylases obtained from a special strain
of B licheniformis, described in more detail in GB-1,269,839 (Novo). Preferred commercially
available amylases include for example, those sold under the tradename Rapidase by
Gist-Brocades, and those sold under the tradename Termamyl and BAN by Novo Industries
A/S. Amylase enzyme may be incorporated into the composition in accordance with the
invention at a level of from 0.0001% to 2% active enzyme by weight of the composition.
[0190] Lipolytic enzyme (lipase) may be present at levels of active lipolytic enzyme of
from 0.0001% to 2% by weight, preferably 0.001% to 1% by weight, most preferably from
0.001% to 0.5% by weight of the compositions.
[0191] The lipase may be fungal or bacterial in origin being obtained. for example, from
a lipase producing strain of
Humicola sp.,
Thermomyces sp. or
Pseudomonas sp. including
Pseudomonas pseudoalcaligenes or
Pseudomas fluorescens. Lipase from chemically or genetically modified mutants of these strains are also
useful herein.
[0192] A preferred lipase is derived from
Pseudomonas pseudoalcaligenes, which is described in Granted European Patent, EP-B-0218272.
[0193] Another preferred lipase herein is obtained by cloning the gene from
Humicola lanuginosa and expressing the gene in
Aspergillus oryza, as host, as described in European Patent Application, EP-A-0258 068, which is commercially
available from Novo Industri A/S, Bagsvaerd, Denmark, under the trade name Lipolase.
This lipase is also described in U.S. Patent 4,810,414, Huge-Jensen et al, issued
March 7, 1989.
Enzyme Stabilizing System
[0194] Preferred enzyme-containing compositions herein may comprise from about 0.001% to
about 10%, preferably from about 0.005% to about 8%,most preferably from about 0.01%
to about 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, and mixtures thereof. Such stabilizing systems
can also comprise reversible enzyme inhibitors, such as reversible protease inhibitors.
[0195] The compositions herein may further comprise from 0 to about 10%, preferably from
about 0.01% to about 6% by weight, of chlorine bleach scavengers, added to prevent
chlorine bleach species present in many water supplies from attacking and inactivating
the enzymes, especially under alkaline conditions. While chlorine levels in water
may be small, typically in the range from about 0.5 ppm to about 1.75 ppm, the available
chlorine in the total volume of water that comes in contact with the enzyme during
washing is usually large; accordingly, enzyme stability in-use can be problematic.
[0196] Suitable chlorine scavenger anions are widely available, and are illustrated by salts
containing ammonium cations or sulfite, bisulfite, thiosulfite, thiosulfate. iodide,
etc. Antioxidants such as carbamate, ascorbate, etc., organic amines such as ethylenediaminetetracetic
acid (EDTA) or alkali metal salt thereof, monoethanolamine (MEA), and mixtures thereof
can likewise be used. Other conventional scavengers such as bisulfate, nitrate, chloride,
sources of hydrogen peroxide such as sodium perborate tetrahydrate, sodium perborate
monohydrate and sodium percarbonate, as well as phosphate, condensed phosphate, acetate,
benzoate, citrate, formate, lactate, malate, tartrate, salicylate, etc. and mixtures
thereof can be used if desired.
Organic polymeric compound
[0197] Organic polymeric compounds are particularly preferred components of the detergent
compositions in accord with the invention. By organic polymeric compound it is meant
essentially any polymeric organic compound commonly used as dispersants, and anti-redeposition
and soil suspension agents in detergent compositions.
[0198] 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.
[0199] Examples of organic polymeric compounds include the water soluble organic homo- or
co-polymeric polycarboxylic acids 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 MWt 2000-5000 and their copolymers with maleic
anhydride, such copolymers having a molecular weight of from 20.000 to 100,000, especially
40,000 to 80,000.
[0200] Other suitable organic polymeric compounds include the polymers of acrylamide and
acrylate having a molecular weight of from 3,000 to 100,000, and the acrylate/fumarate
copolymers having a molecular weight of from 2,000 to 80,000.
[0201] The polyamino 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.
[0202] Terpolymers containing monomer units selected from maleic acid, acrylic acid, polyaspartic
acid and vinyl alcohol, particularly those having an average molecular weight of from
5,000 to 10,000 are also suitable herein.
[0203] Other organic polymeric compounds suitable for incorporation in the detergent compositions
herein include cellulose derivatives such as methylcellulose, carboxymethylcellulose
and hydroxyethylcellulose.
[0204] Further useful organic polymeric compounds are the polyethylene glycols, particularly
those of molecular weight 1000-10000, more particularly 2000 to 8000 and most preferably
about 4000.
Lime soap dispersant compound
[0205] The compositions of the invention may contain a lime soap dispersant compound, which
has a lime soap dispersing power (LSDP), as defined hereinafter of no more than 8,
preferably no more than 7, most preferably no more than 6. The lime soap dispersant
compound is 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.
[0206] 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. A numerical measure
of the effectiveness of a lime soap dispersant is given by the lime soap dispersing
power (LSDP) which is determined using the lime soap dispersion test as described
in an article by H.C. Borghetty and C.A. Bergman, J. Am. Oil. Chem. Soc., volume 27,
pages 88-90, (1950). This lime soap dispersion test method is widely used by practitioners
in this art field being referred to, for example, in the following review articles;
W.N. Linfield, Surfactant Science Series, Volume 7, p3; W.N. Linfield, Tenside Surf.
Det., Volume 27, pages159-161, (1990); and M.K. Nagarajan, W.F. Masler, Cosmetics
and Toiletries, Volume 104, pages 71-73, (1989). The LSDP is the % weight ratio of
dispersing agent to sodium oleate required to disperse the lime soap deposits formed
by 0.025g of sodium oleate in 30ml of water of 333ppm CaCO
3 (Ca:Mg=3:2) equivalent hardness.
[0207] Surfactants having good lime soap dispersant capability will include certain amine
oxides, betaines, sulfobetaines, alkyl ethoxysulfates and ethoxylated alcohols.
[0208] Exemplary surfactants having a LSDP of no more than 8 for use in accord with the
invention include C
16-C
18 dimethyl amine oxide, C
12-C
18 alkyl ethoxysulfates with an average degree of ethoxylation of from 1-5, particularly
C
12-C
15 alkyl ethoxysulfate surfactant with a degree of ethoxylation of about 3 (LSDP=4),
and the C
13-C
15 ethoxylated alcohols with an average degree of ethoxylation of either 12 (LSDP=6)
or 30, sold under the trade names Lutensol A012 and Lutensol A030 respectively, by
BASF GmbH.
[0209] Polymeric lime soap dispersants suitable for use herein are described in the article
by M.K. Nagarajan and W.F. Masler, to be found in Cosmetics and Toiletries, Volume
104, pages 71-73, (1989). Examples of such polymeric lime soap dispersants include
certain water-soluble salts of copolymers of acrylic acid, methacrylic acid or mixtures
thereof, and an acrylamide or substituted acrylamide, where such polymers typically
have a molecular weight of from 5,000 to 20,000.
Suds suppressing system
[0210] The detergent compositions of the 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.
[0211] Suitable suds suppressing systems for use herein may comprise essentially any known
antifoam compound, including, for example silicone antifoam compounds, 2-alkyl and
alcanol antifoam compounds.
[0212] By antifoam compound it is meant herein any compound or mixtures of compounds which
act such as to depress the foaming or sudsing produced by a solution of a detergent
composition, particularly in the presence of agitation of that solution.
[0213] Particularly preferred antifoam compounds for use herein are silicone antifoam compounds
defined herein as any antifoam compound including a silicone component. Such silicone
antifoam compounds also typically contain a silica component. The term "silicone"
as used herein, and in general throughout the industry, encompasses a variety of relatively
high molecular weight polymers containing siloxane units and hydrocarbyl group of
various types. Preferred silicone antifoam compounds are the siloxanes, particularly
the polydimethylsiloxanes having trimethylsilyl end blocking units.
[0214] Other suitable antifoam compounds include the monocarboxylic fatty acids and soluble
salts thereof. These materials are described in US Patent 2,954,347, issued September
27, 1960 to Wayne St. John. The monocarboxylic fatty acids, and salts thereof, for
use as suds suppressor typically have hydrocarbyl chains of 10 to about 24 carbon
atoms, preferably 12 to 18 carbon atoms. Suitable salts include the alkali metal salts
such as sodium, potassium, and lithium salts, and ammonium and alkanolammonium salts.
[0215] Other suitable antifoam compounds include, for example, high molecular weight fatty
esters (e.g. fatty acid triglycerides), fatty acid esters of monovalent alcohols,
aliphatic C
18-C
40 ketones (e.g. stearone) N-alkylated amino triazines such as tri- to hexa-alkylmelamines
or di- to tetra alkyldiamine chlortriazines formed as products of cyanuric chloride
with two or three moles of a primary or secondary amine containing 1 to 24 carbon
atoms, propylene oxide, bis stearic acid amide and monostearyl di-alkali metal (e.g.
sodium, potassium, lithium) phosphates and phosphate esters.
[0216] Copolymers of ethylene oxide and propylene oxide, particularly the mixed ethoxylated/propoxylated
fatty alcohols with an alkyl chain length of from 10 to 16 carbon atoms, a degree
of ethoxylation of from 3 to 30 and a degree of propoxylation of from 1 to 10, are
also suitable antifoam compounds for use herein.
[0217] Suitable 2-alky-alcanols antifoam compounds for use herein have been described in
DE 40 21 265. The 2-alkyl-alcanols suitable for use herein consist of a C
6 to C
16 alkyl chain carrying a terminal hydroxy group, and said alkyl chain is substituted
in the a position by a C
1 to C
10 alkyl chain. Mixtures of 2-alkyl-alcanols can be used in the compositions according
to the present invention.
[0218] A preferred suds suppressing system comprises
(a) antifoam compound, preferably silicone antifoam compound, most preferably a silicone
antifoam compound comprising in combination
(i) polydimethyl siloxane, at a level of from 50% to 99%, preferably 75% to 95% by
weight of the silicone antifoam compound; and
(ii) silica, at a level of from 1% to 50%, preferably 5% to 25% by weight of the silicone/silica
antifoam compound;
wherein said silica/silicone antifoam compound is incorporated at a level of from
5% to 50%, preferably 10% to 40% by weight;
(b) a dispersant compound, most preferably comprising a silicone glycol rake copolymer
with a polyoxyalkylene content of 72-78% and an ethylene oxide to propylene oxide
ratio of from 1:0.9 to 1:1.1, at a level of from 0.5% to 10%, preferably 1% to 10%
by weight; a particularly preferred silicone glycol rake copolymer of this type is
DCO544, commercially available from DOW Corning under the tradename DCO544;
(c) an inert carrier fluid compound, most preferably comprising a C16-C18 ethoxylated alcohol with a degree of ethoxylation of from 5 to 50, preferably 8 to
15, at a level of from 5% to 80%, preferably 10% to 70%, by weight;
[0219] A preferred particulate suds suppressor system useful herein comprises a mixture
of an alkylated siloxane of the type hereinabove disclosed and solid silica.
[0220] The solid silica can be a fumed silica, a precipitated silica or a silica, made by
the gel formation technique. The silica particles suitable have an average particle
size of from 0.1 to 50 micrometers, preferably from 1 to 20 micrometers and a surface
area of at least 50m
2/g. These silica particles can be rendered hydrophobic by treating them with dialkylsilyl
groups and/or trialkylsilyl groups either bonded directly onto the silica or by means
of a silicone resin. It is preferred to employ a silica the particles of which have
been rendered hydrophobic with dimethyl and/or trimethyl silyl groups. A preferred
particulate antifoam compound for inclusion in the detergent compositions in accordance
with the invention suitably contain an amount of silica such that the weight ratio
of silica to silicone lies in the range from 1:100 to 3:10, preferably from 1:50 to
1:7.
[0221] Another suitable particulate suds suppressing system is represented by a hydrophobic
silanated (most preferably trimethyl-silanated) silica having a particle size in the
range from 10 nanometers to 20 nanometers and a specific surface area above 50m
2/g, intimately admixed with dimethyl silicone fluid having a molecular weight in the
range from about 500 to about 200,000 at a weight ratio of silicone to silanated silica
of from about 1:1 to about 1:2.
[0222] A highly preferred particulate suds suppressing system is described in EP-A-0210731
and comprises a silicone antifoam compound and an organic carrier material having
a melting point in the range 50°C to 85°C, wherein the organic carrier material comprises
a monoester of glycerol and a fatty acid having a carbon chain containing from 12
to 20 carbon atoms. EP-A-0210721 discloses other preferred particulate suds suppressing
systems wherein the organic carrier material is a fatty acid or alcohol having a carbon
chain containing from 12 to 20 carbon atoms, or a mixture thereof, with a melting
point of from 45°C to 80°C.
[0223] Other highly preferred particulate suds suppressing systems are described in copending
European Application 91870007.1 in the name of the Procter and Gamble Company which
systems comprise silicone antifoam compound, a carrier material, an organic coating
material and glycerol at a weight ratio of glycerol : silicone antifoam compound of
1:2 to 3:1. Copending European Application 91201342.0 also discloses highly preferred
particulate suds suppressing systems comprising silicone antifoam compound, a carrier
material, an organic coating material and crystalline or amorphous aluminosilicate
at a weight ratio of aluminosilicate : silicone antifoam compound of 1:3 to 3:1. The
preferred carrrier material in both of the above described highly preferred granular
suds controlling agents is starch.
[0224] An exemplary particulate suds suppressing system for use herein is a particulate
agglomerate component, made by an agglomeration process, comprising in combination
(i) from 5% to 30%, preferably from 8% to 15% by weight of the component of silicone
antifoam compound, preferably comprising in combination polydimethyl siloxane and
silica;
(ii) from 50% to 90%, preferably from 60% to 80% by weight of the component, of carrier
material, preferably starch;
(iii) from 5% to 30%, preferably from 10% to 20% by weight of the component of agglomerate
binder compound, where herein such compound can be any compound, or mixtures thereof
typically employed as binders for agglomerates, most preferably said agglomerate binder
compound comprises a C16-C18 ethoxylated alcohol with a degree of ethoxylation of from 50 to 100; and
(iv) from 2% to 15%, preferably from 3% to 10%, by weight of C12-C22 hydrogenated fatty acid.
Polymeric dye transfer inhibiting agents
[0225] The detergent compositions herein may also comprise from 0.01% to 10%, preferably
from 0.05% to 0.5% by weight of polymeric dye transfer inhibiting agents.
[0226] The polymeric dye transfer inhibiting agents are preferably selected from polyamine
N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinylpyrroudonepolymers
or combinations thereof.
a) Polyamine N-oxide polymers
[0227] Polyamine N-oxide polymers suitable for use herein contain units having the following
structure formula :

wherein P is a polymerisable unit, whereto the R-N-O group can be attached to, or
wherein the R-N-O group forms part of the polymerisable unit or a combination of both.

R are aliphatic, ethoxylated aliphatics, aromatic, heterocyclic or alicyclic groups
or any combination thereof whereto the nitrogen of the N-O group can be attached or
wherein the nitrogen of the N-O group is part of these groups.
[0228] The N-O group can be represented by the following general structures :

wherein R1, R2, and R3 are aliphatic groups, aromatic, heterocyclic or alicyclic
groups or combinations thereof, x or/and y or/and z is 0 or 1 and wherein the nitrogen
of the N-O group can be attached or wherein the nitrogen of the N-O group forms part
of these groups. The N-O group can be part of the polymerisable unit (P) or can be
attached to the polymeric backbone or a combination of both. Suitable polyamine N-oxides
wherein the N-O group forms part of the polymerisable unit comprise polyamine N-oxides
wherein R is selected from aliphatic, aromatic, alicyclic or heterocyclic groups.
One class of said polyamine N-oxides comprises the group of polyamine N-oxides wherein
the nitrogen of the N-O group forms part of the R-group. Preferred polyamine N-oxides
are those wherein R is a heterocyclic group such as pyrridine, pyrrole, imidazole,
pyrrolidine, piperidine, quinoline, acridine and derivatives thereof.
[0229] Another class of said polyamine N-oxides comprises the group of polyamine N-oxides
wherein the nitrogen of the N-O group is attached to the R-group.
[0230] Other suitable polyamine N-oxides are the polyamine oxides whereto the N-O group
is attached to the polymerisable unit.
[0231] Preferred class of these polyamine N-oxides are the polyamine N-oxides having the
general formula (I) wherein R is an aromatic,heterocyclic or alicyclic groups wherein
the nitrogen of the N-0 functional group is part of said R group. Examples of these
classes are polyamine oxides wherein R is a heterocyclic compound such as pyrridine,
pyrrole, imidazole and derivatives thereof.
[0232] Another preferred class of polyamine N-oxides are the polyamine oxides having the
general formula (I) wherein R are aromatic, heterocyclic or alicyclic groups wherein
the nitrogen of the N-0 functional group is attached to said R groups. Examples of
these classes are polyamine oxides wherein R groups can be aromatic such as phenyl.
[0233] Any polymer backbone can be used as long as the amine oxide polymer formed is water-soluble
and has dye transfer inhibiting properties. Examples of suitable polymeric backbones
are polyvinyls, polyalkylenes, polyesters, polyethers, polyamide, polyimides, polyacrylates
and mixtures thereof.
[0234] The amine N-oxide polymers of the present invention typically have a ratio of amine
to the amine N-oxide of 10:1 to 1:1000000. However the amount of amine oxide groups
present in the polyamine oxide polymer can be varied by appropriate copolymerization
or by appropriate degree of N-oxidation. Preferably, the ratio of amine to amine N-oxide
is from 2:3 to 1:1000000. More preferably from 1:4 to 1:1000000, most preferably from
1:7 to 1:1000000. The polymers of the present invention actually encompass random
or block copolymers where one monomer type is an amine N-oxide and the other monomer
type is either an amine N-oxide or not. The amine oxide unit of the polyamine N-oxides
has a PKa < 10, preferably PKa < 7. more preferred PKa < 6.
[0235] The polyamine oxides can be obtained in almost any degree of polymerisation. The
degree of polymerisation is not critical provided the material has the desired water-solubility
and dye-suspending power. Typically, the average molecular weight is within the range
of 500 to 1000,000; preferably from 1.000 to 50,000, more preferably from 2,000 to
30,000, most preferably from 3,000 to 20,000.
b) Copolymers of N-vinylpyrrolidone and N-vinylimidazole
[0236] Preferred polymers for use herein may comprise a polymer selected from N-vinylimidazole
N-vinylpyrrolidone copolymers wherein said polymer has an average molecular weight
range from 5,000 to 50,000 more preferably from 8,000 to 30,000, most preferably from
10,000 to 20,000. The preferred N-vinylimidazole N-vinylpyrrolidone copolymers have
a molar ratio of N-vinylimidazole to N-vinylpyrrolidone from 1 to 0.2, more preferably
from 0.8 to 0.3, most preferably from 0.6 to 0.4 .
c) Polyvinylpyrrolidone
[0237] The detergent compositions herein may also utilize polyvinylpyrrolidone ("PVP" having
an average molecular weight of from 2,500 to 400,000, preferably from 5,000 to 200,000,
more preferably from 5,000 to 50,000, and most preferably from 5,000 to 15,000. Suitable
polyvinylpyrrolidones are commercially vailable from ISP Corporation, New York, NY
and Montreal, Canada under the product names PVP K-15 (viscosity molecular weight
of 10,000), PVP K-30 (average molecular weight of 40,000), PVP K-60 (average molecular
weight of 160,000), and PVP K-90 (average molecular weight of 360,000). PVP K-15 is
also available from ISP Corporation. Other suitable polyvinylpyrrolidones which are
commercially available from BASF Cooperation include Sokalan HP 165 and Sokalan HP
12.
[0238] Polyvinylpyrrolidone may be incorporated in the detergent compositions herein at
a level of from 0.01% to 5% by weight of the detergent, preferably from 0.05% to 3%
by weight, and more preferably from 0.1% to 2% by weight. The amount of polyvinylpyrrolidone
delivered in the wash solution is preferably from 0.5 ppm to 250 ppm, preferably from
2.5 ppm to 150 ppm, more preferably from 5 ppm to 100 ppm.
d) Polyvinyloxazolidone
[0239] The detergent compositions herein may also utilize polyvinyloxazolidones as polymeric
dye transfer inhibiting agents. Said polyvinyloxazolidones have an average molecular
weight of from 2,500 to 400,000, preferably from 5,000 to 200,000, more preferably
from 5,000 to 50,000, and most preferably from 5,000 to 15,000.
[0240] The amount of polyvinyloxazolidone incorporated in the detergent compositions may
be from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably
from 0.1% to 2% by weight. The amount of polyvinyloxazolidone delivered in the wash
solution is typically from 0.5 ppm to 250 ppm, preferably from 2.5 ppm to 150 ppm,
more repferably from 5 ppm to 100 ppm.
e) Polyvinylimidazole
[0241] The detergent compositions herein may also utilize polyvinylimidazole as polymeric
dye transfer inhibiting agent. Said polyvinylimidazoles preferably have an average
molecular weight of from 2,500 to 400,000, more preferably from 5,000 to 50,000, and
most preferably from 5,000 to 15,000.
[0242] The amount of polyvinylimidazole incorpoarted in the detergent compositions may be
from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably
from 0.1% to 2% by weight. The amount of polyvinylimidazole delivered in the wash
solution is from 0.5 ppm to 250 ppm, preferably from 2.5 ppm to 150 ppm, more preferably
from 5 ppm to 100 ppm.
Optical brightener
[0243] The detergent compositions herein may also optionally contain from about 0.005% to
5% by weight of certain types of hydrophilic optical brighteners which also provide
a dye transfer inhibition action. If used, the compositions herein will preferably
comprise from about 0.01 % to 1 % by weight of such optical brighteners.
[0244] The hydrophilic optical brighteners useful in the present invention are 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.
[0245] 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.
[0246] 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.
[0247] 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.
[0248] The specific optical brightener species selected for use in the present invention
provide especially effective dye transfer inhibition performance benefits when used
in combination with the selected polymeric dye transfer inhibiting agents hereinbefore
described. The combination of such selected polymeric materials (e.g., PVNO and/or
PVPVI) with such selected optical brighteners (e.g., Tinopal UNPA-GX, Tinopal 5BM-GX
and/or Tinopal AMS-GX) provides significantly better dye transfer inhibition in aqueous
wash solutions than does either of these two detergent composition components when
used alone. Without being bound by theory, it is believed that such brighteners work
this way because they have high affinity for fabrics in the wash solution and therefore
deposit relatively quick on these fabrics. The extent to which brighteners deposit
on fabrics in the wash solution can be defined by a parameter called the "exhaustion
coefficient". The exhaustion coefficient is in general as the ratio of a) the brightener
material deposited on fabric to b) the initial brightener concentration in the wash
liquor. Brighteners with relatively high exhaustion coefficients are the most suitable
for inhibiting dye transfer in the context cf the present invention.
[0249] Of course, it will be appreciated that other, conventional optical brightener types
of compounds can optionally be used in the present compositions to provide conventional
fabric "brightness" benefits, rather than a true dye transfer inhibiting effect. Such
usage is conventional and well-known to detergent formulations.
Softening agents
[0250] Fabric softening agents can also be incorporated into laundry detergent compositions
in accordance with the present invention. These agents may be inorganic or organic
in type. Inorganic softening agents are exemplified by the smectite clays disclosed
in GB-A-1 400 898. Organic fabric softening agents include the water insoluble tertiary
amines as disclosed in GB-A-1 514 276 and EP-B-0 011 340.
[0251] Levels of smectite clay are normally in the range from 5% to 15%, more preferably
from 8% to 12% by weight, with the material being added as a dry mixed component to
the remainder of the formulation. Organic fabric softening agents such as the water-insoluble
tertiary amines or dilong chain amide materials are incorporated at levels of from
0.5% to 5% by weight, normally from 1% to 3% by weight, whilst the high molecular
weight polyethylene oxide materials and the water soluble cationic materials are added
at levels of from 0.1% to 2%, normally from 0.15% to 1.5% by weight.
Other optional ingredients
[0252] Other optional ingredients suitable for inclusion in the compositions of the invention
include perfumes, colours and filler salts, with sodium sulfate being a preferred
filler salt.
Form of the compositions
[0253] The detergent compositions of the invention can be formulated in any desirable form
such as powders, granulates, pastes, liquids and gels.
Liquid compositions
[0254] The detergent compositions of the present invention may be formulated as liquid detergent
compositions. Such liquid detergent compositions typically comprise from 94% to 35%
by weight, preferably from 90% to 40% by weight, most preferably from 80% to 50% by
weight of a liquid carrier, e.g., water, preferably a mixture of water and organic
solvent.
Gel compositions
[0255] The detergent compositions of the present invention may also be in the form of gels.
Such compositions are typically formulated with polyakenyl polyether having a molecular
weight of from about 750,000 to about 4,000,000.
Solid compositions
[0256] The detergent compositions of the invention are preferably in the form of solids,
such as powders and granules.
[0257] The particle size of the components of granular compositions in accordance with the
invention should preferably be such that no more that 5% of particles are greater
than 1.4mm in diameter and not more than 5% of particles are less than 0.15mm in diameter.
[0258] The bulk density of granular detergent compositions in accordance with the present
invention typically have a bulk density of at least 450 g/litre, more usually at least
600 g/litre and more preferably from 650 g/litre to 1200 g/litre.
[0259] Bulk density is measured by means of 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
cylindrial cup disposed below the funnel. The funnel is 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.
[0260] To carry out a measurement, the funnel is filled with powder by hand pouring, the
flap valve is opened and powder allowed to overfill 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 the bulk density in
g/litre. Replicate measurements are made as required.
Making processes - granular compositions
[0261] In general, granular detergent compositions in accordance with the present invention
can be made via a variety of methods including dry mixing, spray drying, agglomeration
and granulation.
Washing methods
[0262] The compositions of the invention may be used in essentially any washing or cleaning
method, including machine laundry and dishwashing methods.
Machine dishwashing method
[0263] A preferred machine dishwashing method comprises treating soiled articles selected
from crockery, glassware, hollowware and cutlery and mixtures thereof, with an aqueous
liquid having dissolved or dispensed therein an effective amount of a machine dishwashing
composition in accord with the inevntion. By an effective amount of the machine dishwashing
composition it is typically 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.
Machine laundry methods
[0264] Machine laundry methods herein 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 composition in accord with the invention. The detergent
can be added to the wash solution either via the dispenser drawer of the washing machine
or by a dispensing device. By an effective amount of the detergent composition it
is typically 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.
[0265] In a preferred washing method herein a dispensing device containing an effective
amount of detergent product is introduced into the drum of a, preferably front-loading,
washing machine before the commencement of the wash cycle.
[0266] The dispensing device is a container for the detergent product which is used to deliver
the product directly into the drum of the washing machine. Its volume capacity should
be such as to be able to contain sufficient detergent product as would normally be
used in the washing method.
[0267] 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
immersion in the wash water.
[0268] 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 components such as water-soluble builder
and heavy metal ion sequestrant components in the drum of the washing machine at this
stage of the wash cycle.
[0269] 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. Especially
preferred dispensing devices for use in accord with the invention have been described
in the following patents; GB-B-2, 157, 717, GB-B-2, 157, 718, EP-A-0201376, EP-A-0288345
and EP-A-0288346. An article by J.Bland published in Manufacturing Chemist, November
1989, pages 41-46 also describes especially preferred dispensing devices for use with
granular laundry products which are of a type commonly know as the "granulette".
[0270] Especially preferred dispensing devices are disclosed in European Patent Application
Publication Nos. 0343069 & 0343070. The latter Application discloses a device comprising
a flexible sheath in the form of a bag extending from a support ring defining an orifice,
the orifice being adapted to admit to the bag sufficient product for one washing cycle
in a washing process. A portion of the washing medium flows through the orifice into
the bag, dissolves the product, and the solution then passes outwardly through the
orifice into the washing medium. The support ring is provided with a masking arrangemnt
to prevent egress of wetted, undissolved, product, this arrangement typically comprising
radially extending walls extending from a central boss in a spoked wheel configuration,
or a similar structure in which the walls have a helical form.
Pretreatment washing method
[0271] In a pretreatment wash method aspect of the invention a soiled/stained substrate
is treated with an effective amount of a pretreatment solution containing a heavy
metal ion sequestrant, but no bleach components. The solution might optionally contain
other non-bleach detergent components such as surfactants, builders, enzymes and detergent
polymers. Preferably the solution also contains water-soluble builder.
[0272] The level of the heavy metal ion sequestrant in said pretreatment solution is typically
from 0.0005 % to 1%, and preferably is more than 0.05%.
[0273] The pretreatment solution is allowed to remain in contact with the soiled substrate
for an effective time interval. Said time interval will typically be from 10 seconds
to 1800 seconds, more preferably from 60 seconds to 600 seconds.
[0274] The soiled substrate is then washed using a suitable washing method wherein a bleach-containing
detergent product is employed. The washing method may for example, be any of the machine
dishwashing or machine laundry washing methods described herein.
[0275] In the detergent compositions, the abbreviated component identifications have the
following meanings:
| XYAS |
Sodium C1X - C1Y alkyl sulfate |
| |
| 24EY |
A C12-14 predominantly linear primary alcohol condensed with an average of Y moles of ethylene
oxide |
| |
| XYEZ |
A C1x - C1y predominantly linear primary alcohol condensed with an average of Z moles of ethylene
oxide |
| |
| XYEZS |
C1X - C1Y sodium alkyl sulfate condensed with an average of Z moles of ethylene oxide per mole |
| |
| TFAA |
C16-C18 alkyl N-methyl glucamide. |
| |
| Silicate |
Amorphous Sodium Silicate (SiO2:Na2O ratio = 2.0) |
| |
| NaSKS-6 |
Crystalline layered silicate of formula δ-Na2Si2O5 |
| |
| Carbonate |
Anhydrous sodium carbonate |
| |
| Polycarboxylate |
Copolymer of 1:4 maleic/acrylic acid, average molecular weight about 80,000 |
| |
| Zeolite A |
Hydrated Sodium Aluminosilicate of formula Na12(AlO2SiO2)12. 27H2O having a primary particle size in the range from 1 to 10 micrometers |
| Citrate |
Tri-sodium citrate dihydrate |
| |
| Percarbonate (fast release particle) |
Anhydrous sodium percarbonate bleach of empirical formula 2Na2CO3.3H2O2 coated with a mixed salt of formula Na2SO4.n.Na2CO3 where n is 0.29 and where the weight ratio of percarbonate to mixed salt is 39:1 |
| |
| Percarbonate (slow release particle) |
Anhydrous sodium percarbonate bleach coated with a coating of sodium silicate (Si2O:Na2O ratio = 2:1) at a weight ratio of percarbonate to sodium silicate of 39:1 |
| |
| TAED |
Tetraacetylethylenediamine |
| |
| TAED (slow release particle) |
Particle formed by agglomerating TAED with citric acid and polyethylene glycol (PEG)
of Mw=4,000 with a weight ratio of components of TAED:citric acid:PEG of 75:10:15,
coated with an external coating of citric acid at a weight ratio of agglomerate: citric
acid coating of 95:5. |
| |
| Benzoyl Caprolactam (slow release particle) |
Particle formed by agglomerating benzoyl caprolactam (BzCl) with citric acid and polyethylene
glycol (PEG) of Mw=4,000, with a weight ratio of components of BzCl:citric acid:PEG
of 63:21:16, coated with an external coating of citric acid at a weight ratio of agglomerate:citric
acid coating of 95:5 |
| |
| TAED (fast release particle) |
Particle formed by agglomerating TAED with partially neutralised polycarboxylate at
a ratio of TAED:polycarboxylate of 93:7, coated with an external coating of polycarboxylate
at a weight ratio of agglomerate:coating of 96:4 |
| EDDS (fast release particle) |
Particle formed by spray-drying EDDS with MgSO4 at a weight ratio of 26:74 |
| |
| Protease |
Proteolytic enzyme sold under the tradename Savinase by Novo Industries A/S with an
activity of 13 KNPU/g. |
| |
| Amylase |
Amylolytic enzyme sold under the tradename Termamyl 60T by Novo Industries A/S with
an activity of 300 KNU/g |
| |
| Cellulase |
Cellulosic enzyme sold by Novo Industries A/S with an activity of 1000 CEVU/g |
| |
| Lipase |
Lipolytic enzyme sold under the tradename Lipolase by Novo Industries A/S with an
activity of 165 KLU/g |
| |
| CMC |
Sodium carboxymethyl cellulose |
| |
| HEDP |
1,1-hydroxyethane diphosphonic acid |
| |
| EDDS |
Ethylenediamine -N, N'- disuccinic acid, [S,S] isomer in the form of the sodium salt. |
| |
| PVNO |
Poly (4-vinylpyridine)-N-oxide copolymer of vinylimidaxole and vinylpyrrolidone having
an average molecular weight of 10,000. |
| |
| Granular Suds Suppressor |
12% Silicone/silica, 18% stearyl alcohol,70% starch in granular form |
| |
| Nonionic |
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
LF404 by BASF Gmbh (low foaming) |
| |
|
| Metasilicate |
Sodium metasilicate (SiO2:Na2O ratio = 1.0) |
| |
| Phosphate |
Sodium tripolyphosphate |
| |
| 480N |
Random copolymer of 3:7 acrylic/methacrylic acid. average molecular weight about 3,500 |
| |
| PB1 |
Anydrous sodium perborate monohydrate - in compacted particulate form to retard release
of hydrogen peroxide |
| |
| Cationic lactam |
Cationic peroxyacid bleach precursor salt of trialkyl ammonium methylene C5-alkyl caprolactam with tosylate |
| |
| DETPMP |
Diethylene triamine penta (methylene phosphonic acid), marketed by Monsanto under
the tradename Dequest 2060 |
| |
| Bismuth nitrate |
Bismuth nitrate salt |
| |
| Paraffin |
Paraffin oil sold under the tradename Winog 70 by Wintershall. |
| |
| BSA |
Amylolytic enzyme sold under the tradename LEI 7 by Novo Industries A/S (approx 1%
enzyme activity) |
| |
| Sulphate |
Anhydrous sodium sulphate. |
| |
| pH |
Measured as a 1% solution in distilled water at 20°C. |
Example 1
[0276] The following laundry detergent compositions were prepared values being expressed
as percentages by weight of the compositions: Composition A is a comparative composition,
compositions B to E are in accord with the invention:
| |
A |
B |
C |
D |
E |
| |
| 45AS/25AS (3:1) |
9.1 |
9.1 |
9.1 |
9.1 |
7.0 |
| 35AE3S |
2.3 |
2.3 |
2.3 |
2.3 |
2.0 |
| 24E5 |
4.5 |
4.5 |
4.5 |
4.5 |
6.0 |
| TFAA |
2.0 |
2.0 |
2.0 |
2.0 |
- |
| Zeolite A |
13.2 |
13.2 |
13.2 |
13.2 |
15.0 |
| Na SKS-6/citric acid (79:21) |
15.6 |
15.6 |
15. 6 |
15.6 |
13.0 |
| Carbonate |
7.6 |
7.6 |
7.6 |
7.6 |
8.0 |
| TAED (fast release particle) |
6.3 |
- |
- |
- |
- |
| TAED (slow release particle) |
- |
5.0 |
- |
2.3 |
3.5 |
| Benzoyl Caprolactam (slow release particle) |
- |
- |
5.0 |
2.7 |
- |
| Percarbonate (fast release particle) |
22.5 |
- |
- |
22.5 |
- |
| Percarbonate (slow release particle) |
- |
22.5 |
22.5 |
- |
- |
| PB1 |
- |
- |
- |
- |
16.0 |
| DETPMP |
0.5 |
- |
- |
- |
0.3 |
| EDDS (fast release particle) |
- |
0.8 |
0.3 |
0.75 |
- |
| Protease |
0.55 |
1.27 |
0.55 |
1.27 |
1.5 |
| Lipase |
0.15 |
0.15 |
0.15 |
0.15 |
0.2 |
| Cellulase |
0.28 |
0.28 |
0.28 |
0.28 |
0.4 |
| Amylase |
0.27 |
0.27 |
0.27 |
0.27 |
0.4 |
| Polycarboxylate |
5.1 |
5.1 |
5.1 |
5.1 |
4.0 |
| CMC |
0.4 |
0.4 |
0.4 |
0.4 |
0.4 |
| PVNO |
0.03 |
0.03 |
0.03 |
0.03 |
- |
| Granular suds suppressor |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
| Minors/misc to 100% |
|
|
|
|
|
[0277] The following T50 values (in seconds) were obtained for each of products A to D:
| T50 |
A |
B |
C |
D |
| |
| Peroxyacid |
130 |
190 |
205 |
240 |
| AVO |
95 |
225 |
230 |
115 |
| Builder (citric) |
90 |
60 |
60 |
60 |
| Heavy metal ion sequestrant (DETPMP or EDDS) |
150 |
30 |
30 |
60 |
Comparative testing
Test method - stain removal
Swatch preparation
[0278] Three white cotton sheets were prewashed in a non-biological bleach-free heavy duty
detergent. Sets of six test swatches of size 6cm x 6cm were cut from each sheet. Stains
were evenly applied onto each swatch set (e.g. by painting on).
[0279] Additionally, pre-prepared swatches obtained from the EMPA institute were also employed.
[0280] In summary, the following sets of swatches were employed:
Enzymatic stains
Grass;
Bleachable stains
EMPA Blood;
EMPA Blood Milk and Ink;
Greasy stains
Dirty Motor Oil;
Shoe Polish;
[0281] The sets of fabric swatches were subjected to one wash cycle in an automatic washing
machine. The swatches were then assessed for removal of the stains by an expert panel
using a four point Scheffe scale. The combined averaged paired results of each of
the sets of comparisons are as set out below, with prior art composition A being used
as the common reference.
[0282] In more detail, a Miele 698 WM automatic washing machine was employed, and the 40°C
short cycle programme selected. Water of 12° German hardness ( Ca : Mg = 3 : 1) was
used. 75g of detergent, dispensed from a granulette dispensing device placed in the
middle of the load was employed. One swatch of each type was washed along with a ballast
load of 2.7 Kg of lightly soiled sheets (1 weeks domestic usage).
Comparative testing - stain removal
[0283] The above stain removal test method was followed in comparing the efficiency of Composition
B with the reference prior art Composition A in removing different type of stains.
[0284] The results obtained were as follows:
| Stain type |
Stain removal benefit (PSU) |
| EMPA blood |
+1.8* |
| EMPA BMI |
+0.6 |
| Grass |
+0.7 |
| Dirty Motor Oil |
+0.6 |
| Shoe polish |
+0.7 |
| *significant at 95 % confidence limit |
Example 2
[0285] The following bleach-containing machine dishwashing compositions were prepared (parts
by weight) in accord with the invention.
| |
A |
B |
C |
D |
E |
F |
G |
| Citrate |
15.0 |
15.0 |
15.0 |
15.0 |
15.0 |
15.0 |
- |
| 480N |
6.0 |
6.0 |
6.0 |
6.0 |
6.0 |
6.0 |
- |
| Carbonate |
17.5 |
17.5 |
17.5 |
17.5 |
17.5 |
17.5 |
- |
| Phosphate |
- |
- |
- |
- |
- |
- |
38.0 |
| Silicate (as SiO2) |
8.0 |
8.0 |
8.0 |
8.0 |
8.0 |
8.0 |
14.0 |
| Metasilicate (as SiO2) |
1.2 |
1.2 |
1.2 |
1.2 |
1.2 |
1.2 |
2.5 |
| PB1 - slow release particle (AvO) |
1.2 |
1.2 |
1.5 |
1.5 |
1.5 |
2.2 |
1.2 |
| TAED (slow release particle) |
2.2 |
2.2 |
2.2 |
3.5 |
- |
2.2 |
2.2 |
| Cationic lactam |
- |
- |
- |
- |
3.3 |
- |
- |
| Paraffin |
0.5 |
0.5 |
0.5 |
0.5 |
0.5 |
0.5 |
0.5 |
| Bismuth nitrate |
- |
0.2 |
0.2 |
0.2 |
0.3 |
0.4 |
0.2 |
| Protease |
2.0 |
2.0 |
2.0 |
2.0 |
2.0 |
2.0 |
2.0 |
| Amylase |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
1.5 |
- |
| BSA |
- |
- |
- |
- |
- |
- |
1.5 |
| DETPMP |
0.13 |
0.13 |
0.13 |
0.13 |
0.13 |
0.13 |
- |
| HEDP |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
1.0 |
- |
| Nonionic |
2.0 |
2.0 |
2.0 |
2.0 |
2.0 |
2.0 |
1.5 |
| Sulphate |
23.0 |
22.8 |
22.4 |
22.7 |
22.2 |
21.5 |
0.3 |
| misc inc moisture to balance |
|
|
|
|
|
|
|
| pH (1% solution) |
10.7 |
10.7 |
10.7 |
10.7 |
10.7 |
10.7 |
11.0 |
Example 3
[0286] The following representative beaker test method was carried out to determine whether
the sequential order of exposure of a stained fabric to heavy metal ion sequestrant
and hydrogen peroxide bleach solution would give rise to differences in the stain
removal profile.
[0287] Pre-stained cotton swatches were prepared by immersing the swatches in a concentrated
tea solution. Tea stains contain high levels of manganese, and are recognised to be
difficult to remove from soiled/stained substrates.
[0288] Individual 1000 ml beakers were charged with solutions containing individually 0.5%
by weight concentration of EDDS, and a hydrogen peroxide solution equivalent to 2%
AvO. Each of the heavy metal ion sequestrant and bleach solutions was buffered to
a pH of 10.5, which is a typical "in wash" pH encountered in a laundry washing method.
[0289] Sets of the pre-stained swatches were subjected to soaking in either, or sequentially
both, of the solutions. The soak time in each solution was 20 minutes. Each soak was
followed by a rinse in dilute NaOH solution.
[0290] In detail, the following wash/soak protocols were employed:
| Set |
Protocol |
| |
| A |
Soaking in bleach solution only |
| B |
Soaking in EDDS solution only |
| C |
Soaking in bleach solution followed by soaking in EDDS solution |
| D |
Soaking in EDDS solution followed by soaking in bleach solution |
[0291] The stain removal results achieved for each wash/soak protocol were assessed using
a Macbeth Spectrometer, measuring the yellowness, whiteness and a, b and I values,
by comparison with a clear white cotton swatch.
[0292] The following results were obtained:
| |
Stained swatch |
A |
B |
C |
D |
| |
| Yellowness |
55.1 |
35.7 |
36.7 |
29.4 |
19.3 |
| Whiteness |
-141.2 |
-92.1 |
-94.1 |
-75.0 |
-50.1 |
| 1 |
-9.7 |
-5.8 |
-8.6 |
-4.5 |
-3.4 |
| a |
3.5 |
-.3 |
2.3 |
0.0 |
-0.7 |
| b |
23.8 |
16.1 |
15.5 |
13.4 |
8.9 |
[0293] Less positive yellowness, a and b values are desirable. More positive whiteness and
1 values are desirable.
[0294] The stain removal results for the set of swatches D are hence seen to be better than
those obtained for swatches A - C. The enhanced stain removal performance obtained
for the sequential exposure of a stained fabric to a heavy metal ion sequestrant containing
solution prior to a bleach-containing solution is thus demonstrated.
Example 4
[0295] The following representative test method demonstrates that significant bleachable
stain removal performance is obtained when stained swatches are treated with a solution
containing heavy metal ion sequestrant prior to being washed in a bleach-containing
detergent product having fast (i.e. uncontrolled rate of release of bleach).
[0296] Pre-stained cotton swatches were prepared by immersing the swatches in a concentrated
tea solution. Tea stains contain high levels of manganese, and are recognised to be
difficult to remove from soiled/stained substrates.
[0297] Individual 1000 ml beakers were charged with solutions containing 0.005% by weight
concentration of EDDS buffered to a pH of 10.5, which is a typical "in wash" pH encountered
in a laundry washing method.
[0298] Sets of the pre-stained swatches were subjected to rinsing in the EDDS solutions
followed by washing in a full scale laundry wash method using a bleach-containing
detergent product. The rinse time in the EDDS solution was set to be either 2 or 5
minutes. The laundry washing method comprised a main wash in a Miele washing machine
at 40°C using soft water. The detergent product employed in this washing method had
fast release of bleach, and had the composition of formulation A of Example 1.
[0299] The effect of the pre-rinsing in the heavy metal ion sequestrant solution prior to
washing was assessed by reference to sets of the pre-stained swatches subjected only
to the full scale laundry wash method.
[0300] Bleachable stain removal was assessed both visually using the well known 4 - point
Scheffé scale utilising panel score units (PSU), and using the Macbeth spectometer
to calculate a % stain removal value.
[0301] The following results were obtained:
| Rinse/Wash Protocol |
% stain removal |
PSU (Scheffé)
VS wash only |
| |
| Wash only |
87 |
- |
| Rinsing for 2 minutes in EDDS solution followed by wash |
92 |
+3* |
| Rinsing for 5 minutes in EDDS solution followed by wash |
97 |
+3* |
| * significant at the 95% confidence level |
[0302] Marked bleachable stain removal benefits are observed for the swatches exposed to
the heavy metal ion sequestrant solution prior to washing in the bleach-containing
detergent product.
Example 5
[0303] The wash/rinse protocol of Example 3 was repeated with the following variations:
1. The 0.005 % of EDDS solution was replaced by a solution containing 0.005% EDDS
and 0.05% sodium citrate, which was also buffered to pH 10.5.
2. The rinse time was set at 3 minutes.
3. Swatches (cotton) stained individually with the following stains were employed:
(a) Blood (EMPA)
(b) Coffee
(c) Red wine
(d) Cocoa
(e) Blood, milk and ink (EMPA)
[0304] The swatches (a) and (e) were obtained from the EMPA organization. Swatches (b) to
(d) were obtained by painting the stains onto prewashed 15 cm x 15 cm samples of white
cotton sheet.
[0305] Using this modified test protocol the effect of pre-rinsing the stained swatches
in a heavy metal ion sequestrant/ builder containing solution prior to washing was
assessed, by comparison with the results obtained for the same stained swatches exposed
solely to the laundry washing method, without any pre-rinsing step.
[0306] The stain removal results were assessed using the Macbeth spectometer to calculate
a % stain removal value.
[0307] The following results were obtained:
| Rinse/Wash protocol |
|
% Stain removal |
| |
| |
|
Blood |
Coffee |
Red Wine |
Cocoa |
BMI |
| |
| Wash only |
|
78 |
76 |
100 |
36 |
70 |
| Rinsing in EDDS/builder solution for 3 minutes prior to wash |
|
100 |
78 |
100 |
34 |
78 |
[0308] Enhanced stain removal performance is hence seen to be obtained when the rinsing
in the builder/heavy metal ion sequestrant solution step was employed prior to the
wash step.