TECHNICAL FIELD
[0001] The present invention relates to a compact liquid detergent used in laundry cleaning
comprising a mixture of chelants.
BACKGROUND TO THE INVENTION
[0002] Chelants are often formulated in detergents because of the presence of metal ions,
which can be detrimental to end performance. Many highly colored stains incorporate
metals. Removal of the metal can often decolorize the stain and/or make it easier
to remove by destabilizing its structure. Metal ions can also catalytically decompose
bleach in a formulation leading to a significantly reduced performance. Especially
transition metal radical ions e.g. Fe, Cu and Mn can accelerate bleach and peroxide
decomposition during washing and bleaching. Water hardness ions e.g. Ca and Mg can
also cause adverse interaction with surfactants used in washing formulations and lead
to a reduction in the effective concentration available. Fatty acids can precipitate
as calcium soaps resulting in the formation of soap scum.
[0003] Chelants are widely used chemicals that control adverse effects of metal ions in
detergent products by chelating the metal. The chelants are often organic compounds,
which form multiple bonds with a single metal ion. Chelants can be introduced into
the detergent in an acid form or in a salt form; normally the salt form increases
the water-solubility of the chelant. However sodium ions will interact with the fatty
acids of the detergent composition resulting in the formation of solid soap. Therefore
chelants need to be formulated into the composition containing as small amount of
sodium ions as possible, nevertheless maintaining the solubility of the chelants.
Another requirement for the chelants is their solubility. Selected chelants need to
be soluble and stay soluble without the requirement of added water into the detergent
composition. Additionally chelants need to be stable in solution during the storage.
[0004] Phosphate containing chelants have been used widely because of phosphates capability
to sequester alkaline earth metals. However, due to legislation in various countries,
level of phosphate in detergents needs to be substantially reduced. Alternatively
detergent manufacturers are supply more phosphate free detergents. Therefore the detergent
composition formulation needs to fulfill the requirements of regulatory requirements
in different countries.
[0005] When formulating the compact liquid detergent composition the chelant needs to be
selected to fulfill the criteria to control the metal ions, be soluble in the detergent
composition, be stable during the preparation and storage and fulfill the regulatory
requirements.
[0006] In addressing these problems, the Applicant has surprisingly found that by combining
chelants diethylene triamine pentaacetate (DTPA), in a sodium salt form with S,S-ethylene
diamine disuccinic acid (EDDS) in a 2-amminoethanol neutralized form or in sodium
salt form, the overall quantity of chelants can be decreased while maintaining good
solubility and high activity level. Additionally the quantity of undesired sodium
ions brought into the compact liquid detergent composition is reduced and therefore
formation of undesired sodium soap is reduced. The compact liquid detergent composition
of the present invention also covers wider regulatory requirements and can be used
as global formulation.
[0007] Chelants are known for incorporation into cleaning compositions. For example, in
WO2009/013534 (Innospec Limited) salt of ethylenediamine disuccinic acid (EDDS) is used to stabilize
the hydrogen peroxide. In
WO2009/013539 (Innospec Limited) magnesium salt of ethylenediamine disuccinic acid (EDDS) is used
in detergent composition in water-soluble, non-hydroscopic solid form. In
WO2009/013541 (Innospec Limited) a mixture of chelants 1-hydroxyethylidene-1,1-diphosphonic acid
(HEDP) and ethylenediamine disuccinic acid (EDDS) is used in detergent compositions.
In
EP 1280882 (Procter & Gamble) chelants are used in liquid fabric softening compositions. In
WO 01/83668 and
WO 02/074893 (both Procter & Gamble) chelants have been used in detergent products. In
WO99/13040 chelants are described for incorporation into granular or aqueous liquid detergent
compositions.
SUMMARY OF THE INVENTION
[0008] A compact liquid detergent composition comprising less than 25% water by weight of
the composition and a mixture of chelants, wherein first chelant is selected from
the group consisting of sodium salt of Ethylenediamine-
N,
N'-disuccinic acid, Ethylenediamine-N,N'-disuccinic acid neutralized by 2-aminoethanol
and mixtures thereof and second chelant is sodium salt of diethylene triamine pentaacetate.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The detergent product of the present invention is a compact liquid detergent suitable
to be used in a water-soluble pouch, more preferably a multi-compartment water-soluble
pouch or as a conventional liquid detergent conserved in containers. The water-soluble
pouch, where present, comprises a water-soluble film and at least a first, and optionally
a second compartment. The first compartment comprises a first composition, comprising
a mixture of chelants. The second compartment comprises a second composition. Preferably
the pouch comprises a third compartment and a third composition. The optionally second
and third compositions are preferably visibly distinct from each other and the first
composition.
Compact liquid detergent composition
[0010] The composition of the present invention is a compact liquid. By the term 'liquid'
it is meant to include liquid, paste, waxy or gel compositions. The liquid composition
may comprise a solid. Solids may include powder or agglomerates, such as micro-capsules,
beads, noodles or one or more pearlised balls or mixtures thereof. Such a solid element
may provide a technical benefit, through the wash or as a pre-treat, delayed or sequential
release component. Alternatively it may provide an aesthetic effect.
[0011] By the term 'compact' is meant to include liquid, paste, waxy or gel compositions
which comprise less than 25% of water by the weight of the composition.
[0012] In a preferred embodiment the present composition is in the form of a water-soluble
pouch, more preferably a multi-compartment pouch. The water-soluble pouch, wherein
present, comprises a water-soluble film and at least a first, and optionally a second
compartment. The first compartment comprises a first composition, comprising the mixture
of chelants. The second compartment comprises a second, preferably different composition.
Chelants
[0013] The chelants are used in the present invention to control metal ion content, to stabilize
bleach in washing solution and during storage and increase the stain removal by abstracting
metal ions from the stains.
[0014] Chelants are molecules which form coordinate-covalent bonds with metal ions to form
chelates. Chelates are coordination compounds in which a central metal atom bonds
one or more atoms in at least one other molecule or ion called ligand such that at
least one heterocyclic ring is formed with the metal ion as part of the each ring.
Chelants are widely used in detergents, soaps, cleaning products and water treatment.
Chelants are typically polyvalent molecules, usually aminocarboxylates having at least
two binding site. The effectiveness of the chelants can be measured by measuring the
binding constant with the various metals. Within limits, chelants are usually more
effective at increasing wash solution pH, which prevents protonation of chelants.
[0015] The applicant has discovered that by combining chelants diethylene triamine pentaacetate
(DTPA) in sodium salt form with S,S- Ethylenediamine-N,N'-disuccinic acid (EDDS) in
2-aminoethanol (MEA) neutralized form or in a sodium salt form, creates a synenergy
between the chelants, and quantity of chelants can be decreased while maintaining
high activity level and desired solubility. This permits more flexibility in formulation.
Additionally the quantity of undesired sodium ions brought into compact liquid detergent
composition is reduced. Reduced level of chelants improves the solubility and stability
of chelants and permits the use of mixture of chelants in compact liquid detergent
compositions. The compact liquid detergent composition of the present invention also
covers wider regulatory requirements because the chelants do not contain any phosphates.
[0016] The chelants are preferably both in the fully neutralized form; however the acid
form or partially neutralized forms of Ethylenediamine-
N,N'-disuccinic acid are encompassed in the invention.
[0017] The chelant mixture preferably comprises from 1 : 10 molar ratio of diethylene triamine
pentaacetate and ethylenediamine-N,N' disuccinic acid or their salts to 10 : 1 molar
ratio of diethylene triamine pentaacetate and ethylenediamine-N-N disuccinic acid
or their salts.
[0018] EDDS is an effective chelating agent of transitional metals and heavy metals. Transitional
metals may cause problems in compositions containing bleaching agents as they can
cause decomposition of peroxide species. This may cause reduced bleaching performance
and creation of hydroxyl radicals which can cause fibre damage and reduce product
stability. EDDS has two stereogenic centers and therefore has three possible stereo
isomers. The mixture of the chelants in a present invention may include any of the
stereoisomers. Thus it may be selected from [R,R]-EDDS, [R,S]-EDDS, [S,S]-EDDS and
any combinations thereof. Preferably the EDDS is present in substantially the [S,S]-form.
Preferably at least 50%, more preferably at least 70% of the EDDS is of the [S,S]
configuration. [S,S] - EDDS form of EDDS is biodegradable and therefore most preferred
stereoisomer.
[0019] EDDS can be present in compact liquid detergent composition in sodium salt or MEA
neutralied form, preferably in MEA neutralied form.
[0020] DTPA is an effective chelating agent of transitional metals and heavy metals. DTPA
is a polyamino carboxylic acid consisting of a diethylenetriamine backbone modified
with five carboxymethyl groups. DTPA is used as its conjugate base, which has a high
affinity for metal cations.
[0021] DTPA can be present in a compact liquid detergent composition preferably DTPA in
metal salt form. More preferably the DTPA is present in compact liquid detergent composition
in the form of sodium salt comprising from 2 to 5 moles of sodium per mole of DTPA.
[0022] The chelants are added to the composition preferably in liquid form and they preferably
stay in liquid form during preparation, storage and usage. DTPA is water-soluble in
1:2 ratio with sodium and EDDS is water-soluble in aminoethanol neurtalised form or
in 1:2 ratio with sodium.
[0023] In a preferred embodiment the combination of chelants in the present invention comprises
from ten moles of EDDS MEA neutralized form per one mole of DTPA sodium salt to one
mole of EDDS MEA neutralized form per ten moles of DTPA sodium salt.
[0024] The composition of the present invention comprises mixture of chelants from 0.05%
to 5% by weight of a composition, preferably from 0.1% to 4% by weight of the composition
and most preferably from 0.5% to 2.0% by weight of the composition.
Optional compact liquid detergent composition components
[0025] The compositions of the present invention may comprise one or more of the ingredients
as discussed below.
Solvent system
[0026] The solvent system in the present compact liquid detergent compositions can be a
mixture of organic solvents. The present composition does not contain any added water.
High water content may have an unwanted effect on the film properties. Additionally
too high or too low water content may have negative impact on detergent composition
i.e. by causing phase separation. The water in the composition origins from the raw
materials. Preferred organic solvents include 1,2-propanediol, ethanol, glycerol,
dipropylene glycol, methyl propane diol and mixtures thereof. Other lower alcohols,
C
1-C
4 alkanolamines such as monoethanolamine and triethanolamine, can also be used. Solvent
systems can be absent, for example from anhydrous solid embodiments of the invention,
but more typically are present at levels in the range of from 0.1% to 98%, preferably
at least 1% to 50%, more usually from 5% to 25%.
[0027] Water is typically present at levels in the range from 5% to 25%, preferably from
7% to 20% more preferably from 8% to 15% by the weight of the compact liquid detergent
composition.
Surfactants
[0028] The composition of the present invention may comprise surfactants, which are used
in present invention as detersive surfactant for soil suspension purposes.
[0029] Surfactants utilized can be of the anionic, nonionic, zwitterionic, ampholytic or
cationic type or can comprise compatible mixtures of these types. More preferably
surfactants are selected from the group consisting of anionic, nonionic, cationic
surfactants and mixtures thereof. Preferably the compositions are substantially free
of betaine surfactants. Detergent surfactants useful herein are described in
U.S. Patent 3,664,961, Norris, issued May 23, 1972,
U.S. Patent 3,919,678, Laughlin et al., issued December 30, 1975,
U.S. Patent 4,222,905, Cockrell, issued September 16, 1980, and in
U.S. Patent 4,239,659, Murphy, issued December 16, 1980. Anionic and nonionic surfactants are preferred.
[0030] Useful anionic surfactants can themselves be of several different types. For example,
water-soluble salts of the higher fatty acids, i.e., "soaps", are useful anionic surfactants
in the compositions herein. This includes alkali metal soaps such as the sodium, potassium,
ammonium, and alkyl ammonium salts of higher fatty acids containing from 8 to 24 carbon
atoms, and preferably from 12 to 18 carbon atoms. Soaps can be made by direct saponification
of fats and oils or by the neutralization of free fatty acids. Particularly useful
are the sodium and potassium salts of the mixtures of fatty acids derived from coconut
oil and tallow, i.e., sodium or potassium tallow and coconut soap.
[0031] Additional non-soap anionic surfactants which are suitable for use herein include
the water-soluble salts, preferably the alkali metal, and ammonium salts, of organic
sulfuric reaction products having in their molecular structure an alkyl group containing
from 10 to 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included
in the term "alkyl" is the alkyl portion of acyl groups.) Examples of this group of
synthetic surfactants are a) the sodium, potassium and ammonium alkyl sulfates, especially
those obtained by sulfating the higher alcohols (C
8-C
18 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut
oil; b) the sodium, potassium and ammonium alkyl polyethoxylate sulfates, particularly
those in which the alkyl group contains from 10 to 22, preferably from 12 to 18 carbon
atoms, and wherein the polyethoxylate chain contains from 1 to 15, preferably 1 to
6 ethoxylate moieties; and c) the sodium and potassium alkylbenzene sulfonates in
which the alkyl group contains from 9 to 15 carbon atoms, in straight chain or branched
chain configuration, e.g., those of the type described in
U.S. Patents 2,220,099 and
2,477,383. Especially valuable are linear straight chain alkylbenzene sulfonates in which the
average number of carbon atoms in the alkyl group is from 11 to 13, abbreviated as
C
11-C
13 LAS.
[0032] Preferred nonionic surfactants are those of the formula R
1(OC
2H
4)
nOH, wherein R
1 is a C
10-C
16 alkyl group or a C
8-C
12 alkyl phenyl group, and n is from 3 to 80. Particularly preferred are condensation
products of C
12-C
15 alcohols with from 5 to 20 moles of ethylene oxide per mole of alcohol, e.g., C
12-C
13 alcohol condensed with 6.5 moles of ethylene oxide per mole of alcohol.
[0033] The composition of the present invention comprises from 1% to 80% surfactant by weight
of a composition. Surfactant is a component of the first composition. Preferably said
first composition comprises from 5% to 50% surfactant by weight of composition. The
second and third compositions, where present, may comprise surfactant at levels of
from 0.1 to 99.9%.
[0034] When the selected surfactant is LAS, the composition comprises preferably from 5%
to 30% of LAS by weight of the compact liquid detergent composition, more preferably
from 7% to 25% of LAS by weight of the compact liquid detergent composition.
Surfactant boosting polymers
[0035] The composition of the present invention may optionally comprise polymers. Polymers
suitable for the present invention can boost the efficacy of the surfactant, thus
they are called surfactant boosting polymers. The most common purpose of a surfactant
is to emulsify or disperse one liquid phase into another - usually the oil phase into
water. When two immiscible liquids are in contact, a boundary forms between them.
Increasing the interface area, results in the dispersion of one phase into another
as small droplets. The lower the interfacial tension is the more one phase is emulsified
into other. Therefore a low interfacial tension is correlated with cleaning efficiency
in cleaning and laundering. By the term surfactant boosting polymer is meant polymers
capable of decreasing the time to reach the interfacial tension equilibrium of the
surfactant.
[0036] Additionally surfactant boosting polymers aid the collapse of micelles on fats. A
key feature of the surfactant boosting polymer is their amphiphilicity. They have
a balanced ratio of hydrophobic and hydrophilic structural elements. Hence they are
firstly hydrophobic enough to absorb a hydrophobic soil and to remove it with the
surfactants from a surface. Secondly it is hydrophilic enough to keep the detached
hydrophobic soil in the washing and cleaning liquor and prevent it from redepositing
onto the surface. For example in the polyethylene glycol polyvinyl acetate (PEG-PVAc)
polymer; hydrophobic PVAc part of the PEG-PVAc polymer ensures interaction with surfactant
and hydrophobic grease stains, while the hydrophilic polyethylene glycol PEG part
of the PEG-PVAc polymer keeps polymer-surfactant structures dispersed in water.
[0037] The amphiphilic surfactant boosting polymers in a present invention are preferably
based on water-soluble polyalkylene oxides as the hydrophilic back bone and hydrophobic
side chains formed by polymerization of a vinyl ester component. Said polymers preferably
have an average of one or less graft site per 50 alkylene oxide units and mean molar
masses M
w from 3000 to 100,000.
[0038] Most preferred surfactant boosting polymers for the present invention are known under
the trade reference Sokalan PG101 (PEG-PVAc), Sokalan and Sokalan HP22 sold by BASF
Aktiengesellschaft, Ludwigshafen, Germany. Surfactant boosting polymers useful herein
are described in
WO 2007/138053 (BASF Aktiengesellesschaft),
WO/2007/138054 (Procter & Gamble Company).
[0039] The compact liquid detergent composition of the present application comprises from
0.1% to 10% surfactant boosting polymer by weight of the compact liquid detergent
composition, preferably from 3% to 8% surfactant boosting polymer by weight of the
compact liquid detergent composition and more preferably about 4% surfactant boosting
polymer by weight of the compact liquid detergent composition.
Opacifier
[0040] The compact liquid detergent composition may comprise an opacifier. An opacifier
according to the present invention is a solid, inert compound which does not dissolve
in the composition and refracts, scatters or absorbs most light wavelengths.
[0041] The opacifier is preferably selected from the group consisting of styrene/acrylate
latexes, titanium dioxide, tin dioxide, any forms of modified TiO
2, for example carbon modified TiO
2 or metallic doped (e.g. Platinum, Rhodium) TiO
2 or stannic oxide, bismuth oxychloride or bismuth oxychloride coated TiO
2/Mica, silica coated TiO
2 or metal oxide coated and mixtures thereof. Particularly preferred styrene/acrylate
latexes are those available from the Rohm & Haas Company sold under the trademark
Acusol. The latexes are characterized by pH of about 2 to about 3, having approximately
40% solids in water, with particle size of about 0.1 to about 0.5 micron. Specifically
preferred Acusol.RTM. polymers include Acusol.RTM. OP301 (styrene/acrylate) polymer,
Acusol.RTM. OP302, (Styrene/Acrylate/Divinylbenzene Copolymer), Acusol.RTM. OP303
(Styrene/Acrylamide Copolymer), Acusol.RTM. OP305 (Styrene/PEG-10 Maleate/Nonoxynol-10
Maleate/Acrylate Copolymer) and (Styrene/Acrylate/PEG-10 Dimaleate Copolymer) and
mixtures thereof. Preferred species have molecular weight of from 1000 to 1 000 000,
more preferably from 2000 to 500 000, most preferably from 5000 to 20 000.
[0042] The opacifier is preferably present in sufficient amount to leave the composition,
in which it is incorporated, white. Where the opacifier is an inorganic opacifier
(e.g. TriO
2, or modifications thereof) the opacifier is preferably present at a level of from
0.001% to 1%, more preferably from 0.01% to 0.5%, most preferably from 0.05% to 0.15%
by weight of the compact liquid detergent composition.
[0043] Where the opacifier is an organic opacifier (e.g. styrene/acrylate latexes), the
opacifier is preferably present at a level of from 0.001% to 2.5%, more preferably
from 1% to 2.2%, most preferably from 1.4% to 1.8% by weight of the compact liquid
detergent composition.
Antioxidant
[0044] The compact liquid detergent composition may comprise an antioxidant. The second
and third compositions, when present, may also comprise antioxidant. Although not
wishing to be bound by theory, the Applicants believe that the presence of antioxidant
reduced or preferably stops the reaction of reactive compounds in the formula e.g.
perfumes, which tend to be oxidized over time and higher temperature and which can
lead to yellowing.
[0045] An antioxidant according to the present invention, is a molecule capable of slowing
or preventing the oxidation of other molecules. Oxidation reactions can produce free
radicals, which in turn can start chain reactions of degradation. Antioxidants terminate
these chain reactions by removing the free radical intermediates and inhibiting other
oxidation reactions by being oxidized themselves. As a result antioxidants are often
reducing agents. The antioxidant is preferably selected from the group consisting
of butylated hydroxyl toluene (BHT), butylated hydroxyl anisole (BHA), trimethoxy
benzoic acid (TMBA), α, β, λ and δ tocophenol (vitamin E acetate), 6 hydroxy-2,5,7,8
- tetra-methylchroman -2-carboxylic acid (trolox), 1,2, benzisothiazoline - 3-one
(proxel GLX), tannic acid, galic acid, Tinoguard AO-6, Tinoguard TS, ascorbic acid,
alkylated phenol, ethoxyquine 2,2,4 trimethyl, 1-2-dihydroquinoline, 2,6 di or tert
or butyl hydroquinone, tert, butyl, hydroxyl anisole, lignosulphonic acid and salts
thereof, benzofuran, benzopyran, tocopherol sorbate, butylated hydroxyl benzoic acid
and salts thereof, galic acid and its alkyl esters, uric acid, salts thereof and alkyl
esters, sorbic acid and salts thereof, dihydroxy fumaric acid and salts thereof, and
mixtures thereof. Preferred antioxidants are those selected from the group consisting
of alkali and alkali earth metal sulfites and hydrosulfites, more preferably sodium
sulfite or hydrosulfite.
[0046] The antioxidant is preferably present at a level of from 0.01% to 2%, more preferably
from 0.1% to 1%, most preferably from 0.3% to 0.5% by weight of the compact liquid
detergent composition.
[0047] Where inorganic opacifier is used, the opacifier and antioxidant are preferably present
at a ratio of from 0.1 to 0.5, more preferably from 0.12 to 0.35. Whereas, where an
organic opacifier is used, opacifier and antioxidant are preferably present at a ratio
of from 2 to 6, more preferably from 3 to 5.
Rheology modifier
[0048] In a preferred embodiment the compact liquid detergent composition comprises a rheology
modifier. The rheology modifier is selected from the group consisting of non-polymeric
crystalline, hydroxy-functional materials, polymeric rheology modifiers which impart
shear thinning characteristics to the aqueous liquid matrix of the composition. Crystalline,
hydroxy-functional materials are rheology modifiers which form thread-like structuring
systems throughout the matrix of the composition upon in situ crystallization in the
matrix. Specific examples of preferred crystalline, hydroxyl-containing rheology modifiers
include castor oil and its derivatives. Especially preferred are hydrogenated castor
oil derivatives such as hydrogenated castor oil and hydrogenated castor wax. Commercially
available, castor oil-based, crystalline, hydroxyl-containing rheology modifiers include
THIXCIN
® from Rheox, Inc. (now Elementis). Polymeric rheology modifiers are preferably selected
from polyacrylates, polymeric gums, other non-gum polysaccharides, and combinations
of these polymeric materials. Preferred polymeric gum materials include pectine, alginate,
arabinogalactan (gum Arabic), carrageenan, gellan gum, xanthan gum, guar gum and mixtures
thereof.
Fabric care benefit agents
[0049] The compact liquid detergent compositions may comprise a fabric care benefit agent.
As used herein, "fabric care benefit agent" refers to any material that can provide
fabric care benefits such as fabric softening, color protection, pill/fuzz reduction,
anti-abrasion, anti-wrinkle, and the like to garments and fabrics, particularly on
cotton and cotton-rich garments and fabrics, when an adequate amount of the material
is present on the garment/fabric. Nonlimiting examples of fabric care benefit agents
include cationic surfactants, silicones, polyolefin waxes, latexes, oily sugar derivatives,
cationic polysaccharides, polyurethanes, fatty acids and mixtures thereof. Fabric
care benefit agents when present in the compact liquid detergent composition, are
suitably at levels of up to 30% by weight of the compact liquid detergent composition,
more typically from 1% to 20%, preferably from 2% to 10%.
Detersive enzymes
[0050] Suitable detersive enzymes for use herein include protease, amylase, lipase, cellulase,
carbohydrase including mannanase and endoglucanase, and mixtures thereof. Enzymes
can be used at their art-taught levels, for example at levels recommended by suppliers
such as Novo and Genencor. Typical levels in the compact liquid detergent compositions
are from 0.0001% to 5%. When enzymes are present, they can be used at very low levels,
e.g., from 0.001% or lower, in certain embodiments of the invention; or they can be
used in heavier-duty laundry detergent formulations in accordance with the invention
at higher levels, e.g., 0.1% and higher. In accordance with a preference of some consumers
for "non-biological" detergents, the present invention includes both enzyme-containing
and enzyme-free embodiments.
Deposition aid
[0051] As used herein, "deposition aid" refers to any cationic polymer or combination of
cationic polymers that significantly enhance the deposition of a fabric care benefit
agent onto the fabric during laundering. Preferably, the deposition aid is a cationic
or amphoteric polymer. The amphoteric polymers of the present invention will also
have a net cationic charge, i.e.; the total cationic charges on these polymers will
exceed the total anionic charge. Nonlimiting examples of deposition enhancing agents
are cationic polysaccharides, chitosan and its derivatives and cationic synthetic
polymers. Preferred cationic polysaccharides include cationic cellulose derivatives,
cationic guar gum derivatives, chitosan and derivatives and cationic starches.
Builder
[0052] The compact liquid detergent compositions may optionally comprise a builder. Suitable
builders include polycarboxylate builders include cyclic compounds, particularly alicyclic
compounds, such as those described in
U.S. Patents 3,923,679;
3,835,163;
4,158,635;
4,120,874 and
4,102,903. Particularly preferred are citrate builders, e.g., citric acid and soluble salts
thereof (particularly sodium salt). Other preferred builders include aluminosilicates
such as zeolite A, B or MAP; fatty acids or salts, preferably sodium salts, thereof,
preferably C12-C18 saturated and/or unsaturated fatty acids; and alkali or alkali
earth metal carbonates preferably sodium carbonate.
[0053] The compact liquid detergent composition of the present application comprises from
2% to 20% fatty acids by weight of the compact liquid detergent composition, preferably
from 5% to 15% fatty acids by weight of the compact liquid detergent composition and
most preferably from 6% to 10% fatty acids by the weight of the compact liquid detergent
composition.
Bleaching system
[0054] Bleaching agents suitable herein include chlorine and oxygen bleaches, especially
inorganic perhydrate salts such as sodium perborate mono-and tetrahydrates and sodium
percarbonate optionally coated to provide controlled rate of release (see, for example,
GB-A-1466799 on sulfate/carbonate coatings), preformed organic peroxyacids and mixtures thereof
with organic peroxyacid bleach precursors and/or transition metal-containing bleach
catalysts (especially manganese or cobalt). Inorganic perhydrate salts are typically
incorporated at levels in the range from 1% to 40% by weight, preferably from 2% to
30% by weight and more preferably from 5% to 25% by weight of compact liquid detergent
composition. Peroxyacid bleach precursors preferred for use herein include precursors
of perbenzoic acid and substituted perbenzoic acid; cationic peroxyacid precursors;
peracetic acid precursors such as TAED, sodium acetoxybenzene sulfonate and pentaacetylglucose;
pernonanoic acid precursors such as sodium 3,5,5-trimethylhexanoyloxybenzene sulfonate
(iso-NOBS) and sodium nonanoyloxybenzene sulfonate (NOBS); amide substituted alkyl
peroxyacid precursors (
EP-A-0170386); and benzoxazin peroxyacid precursors (
EP-A-0332294 and
EP-A-0482807). Bleach precursors are typically incorporated at levels in the range from 0.5% to
25%, preferably from 1% to 10% by weight of composition while the preformed organic
peroxyacids themselves are typically incorporated at levels in the range from 0.5%
to 25% by weight, more preferably from 1% to 10% by weight of compact liquid detergent
composition. Bleach catalysts preferred for use herein include the manganese triazacyclononane
and related complexes (
US-A-4246612,
US-A-5227084); Co, Cu, Mn and Fe bispyridylamine and related complexes (
US-A-5114611); and pentamine acetate cobalt(III) and related complexes(
US-A-4810410).
Whitening agent
[0055] A compact liquid detergent composition may comprise a whitening agent. Such dyes
have been found to exhibit good tinting efficiency during a laundry wash cycle without
exhibiting excessive undesirable build up during laundering. The whitening agent is
included in the total laundry detergent composition in an amount sufficient to provide
a tinting effect to fabric washed in a solution containing the detergent. In one embodiment,
a multi-compartment pouch comprises, by weight, from 0.0001% to 1%, more preferably
from 0.0001% to 0.5% by weight of the compact liquid detergent composition, and even
more preferably from 0.0001% to 0.3% by weight of the compact liquid detergent composition.
Pearlescent agent
[0056] The compact liquid detergent compositions of the present invention may comprise a
pearlescent agent. Said pearlescent agent may be organic or inorganic, but is preferably
inorganic. Most preferably the pearlescent agent is selected from mica, TiO
2 coated mica, bismuth oxychloride or mixtures thereof.
Perfume
[0057] Perfumes are preferably incorporated into the compact liquid detergent compositions
of the present invention. The perfumes may be prepared as a premix liquid, may be
linked with a carrier material, such as cyclodextrin or may be encapsulated. When
encapsulated the perfumes are preferably encapsulated in a melamine/formaldehyde coating.
Other adjuncts
[0058] Examples of other suitable cleaning adjunct materials include, but are not limited
to; enzyme stabilizing systems; scavenging agents including fixing agents for anionic
dyes, complexing agents for anionic surfactants, and mixtures thereof; optical brighteners
or fluorescers; soil release polymers; dispersants; suds suppressors; dyes; colorants;
hydrotropes such as toluenesulfonates, cumenesulfonates and naphthalenesulfonates;
color speckles; colored beads, spheres or extrudates; clay softening agents and mixtures
thereof.
Composition preparation
[0059] The compact detergent compositions herein can generally be prepared by mixing the
ingredients together. If a pearlescent material is used it should be added in the
late stages of mixing. If a rheology modifier is used, it is preferred to first form
a pre-mix within which the rheology modifier is dispersed in a portion of the water
and optionally other ingredients eventually used to comprise the compositions. This
pre-mix is formed in such a way that it forms a structured liquid. To this structured
pre-mix can then be added, while the pre-mix is under agitation, the surfactant(s)
and essential laundry adjunct materials, along with water and whatever optional detergent
composition adjuncts are to be used.
Pouch material
[0060] When the compact liquid detergent composition is packed into the pouches, the pouch
is preferably made of a film material which is soluble or dispersible in water, and
has a water-solubility of at least 50%, preferably at least 75% or even at least 95%.
The water-solubility is measured by the method set out here after using a glass-filter
with a maximum pore size of 20 microns: 50 grams ± 0.1 gram of pouch material is added
in a pre-weighed 400 ml beaker and 245ml ± 1ml of distilled water is added. This is
stirred vigorously on a magnetic stirrer set at 600 rpm, for 30 minutes. Then, the
mixture is filtered through a folded qualitative sintered-glass filter with a pore
size as defined above (max. 20 micron). The water is dried off from the collected
filtrate by any conventional method, and the weight of the remaining material is determined
(which is the dissolved or dispersed fraction). Then, the percentage solubility or
dispersability can be calculated.
[0061] Preferred pouch materials are polymeric materials, preferably polymers which are
formed into a film or sheet. The pouch material can, for example, be obtained by casting,
blow-moulding, extrusion or blown extrusion of the polymeric material, as known in
the art.
[0062] Preferred polymers, copolymers or derivatives thereof suitable for use as pouch material
are described in
WO03/045812 (Procter & Gamble Company),
WO04/085586 (Procter & Gamble Company) and
WO07/130684 (Procter & Gamble Company).
[0063] Preferably, the level of polymer in the pouch material, for example a PVA polymer,
is at least 60%. The polymer can have any weight average molecular weight, preferably
from 1000 to 1,000,000, more preferably from 10,000 to 300,000 yet more preferably
from 20,000 to 150,000.
[0064] Mixtures of polymers can also be used as the pouch material. This can be beneficial
to control the mechanical and/or dissolution properties of the compartments or pouch,
depending on the application thereof and the required needs. Suitable mixtures include
for example mixtures wherein one polymer has a higher water-solubility than another
polymer, and/or one polymer has a higher mechanical strength than another polymer.
Also suitable are mixtures of polymers having different weight average molecular weights.
[0065] Naturally, different film material and/or films of different thickness may be employed
in making the compartments of the present invention. A benefit in selecting different
films is that the resulting compartments may exhibit different solubility or release
characteristics.
[0066] Most preferred pouch materials are PVA films known under the trade reference Monosol
M8630, as sold by MonoSol LLC of Gary, Indiana, US, and PVA films of corresponding
solubility and deformability characteristics. Other films suitable for use herein
include films known under the trade reference PT film or the K-series of films supplied
by Aicello, or VF-HP film supplied by Kuraray.
[0067] The pouch material herein can also comprise one or more additive ingredients. For
example, it can be beneficial to add plasticisers, for example glycerol, ethylene
glycol, diethyleneglycol, propylene glycol, sorbitol and mixtures thereof. Other additives
include functional detergent additives to be delivered to the wash water, for example
organic polymeric dispersants, etc.
[0068] For reasons of deformability pouches or pouch compartments containing a component
which is liquid will preferably contain an air bubble having a volume of up to 50%,
preferably up to 40%, more preferably up to 30%, more preferably up to 20%, more preferably
up to 10% of the volume space of said compartment.
Process for making the water-soluble pouch
[0069] The process of making the water-soluble pouch may be made using any suitable equipment
and method. Single compartment pouches are made using vertical, but preferably horizontal
form filling techniques commonly known in the art.
[0070] The process for making a water-soluble pouch has been described in
EP1504994 (Procter & Gamble Company) and
WO02/40351 (Procter & Gamble Company). The process for making a multi-compartment water-soluble
pouch has been described in co-pending patent application
09161692.0 filed June 2009 (Procter & Gamble Company).
Secondary Packaging
[0071] The multi-compartment pouches of the present invention are preferably further packaged
in an outer package. Said outer package may be a see-through or partially see-through
container, for example a transparent or translucent bag, tub, carton or bottle. The
pack can be made of plastic or any other suitable material, provided the material
is strong enough to protect the pouches during transport. This kind of pack is also
very useful because the user does not need to open the pack to see how many pouches
there are left. Alternatively, the pack can have non-see-through outer packaging,
perhaps with indicia or artwork representing the visually-distinctive contents of
the pack.
Process of washing
[0072] The compact liquid detergent of the present invention is suitable for laundry cleaning
applications. The compact liquid detergent is suitable for hand or machine washing
conditions. When machine washing, the compact liquid detergent may be delivered from
the dispensing drawer or may be added directly into the washing machine drum either
in a form of water-soluble pouches or in a form of compact liquid.
Examples
[0073] The following are examples of the pouch products of the present invention:
Formulation:
| |
Composition A |
Composition B |
| Ingredient Name |
WT% |
WT% |
| |
|
|
| Linear Alkyl benzene sulfonic acid |
16 |
14 |
| C12-14 alkyl ethoxy 3-sulfate MEA salt |
10 |
13 |
| C12-14 alkyl 7-ethoxylate |
9 |
15 |
| C12-18 Fatty acid |
15 |
8 |
| Sodium - Diethylenetriaminepentaacetate |
0.5 |
0.7 |
| H-EDDS1 |
0.7 |
|
| Na-EDDS |
-- |
1.0 |
| Enzymes |
2.3 |
2.3 |
| Solvent |
15 |
14 |
| Buffer (Monoethanol amine) |
To pH 7.5 |
To pH 7.5 |
| Water |
10 |
15 |
| Miscellaneous/Minors |
to 100 |
to 100 |
| 1H-EDDS: Ethylenediamine-N,N'-disuccinic acid |
Performance:
[0074] The performance of the chelants were measured on wine and tea. Wine and tea stains
were applied to cotton and obtained from EMC (US). Stains and ballast load consisting
of 0.5kg of T-shirt was added to a MiniWasher representing a medium US wash conditions.
The wash water was set at 32.2 °C ± 1 °C and 6gpg (1mmol/L) hardness and the rinse
water was set at 15.5 °C ± 1 °C. The water volume was 15 liters and wash time 12 minutes.
[0075] The stains and the ballast were dried at the end of each cycle under high speed and
high heat with cool down cycle. The results were then analyzed by image analysis which
is a method that enables to calculate the amount of stain that is removed. Stains
are imaged before washing and after washing. The imaging calculates the amount of
stain removal index (SRI). SRI of 100 means complete removal and SRI of zero is no
removal.
[0076] The Laundry Image Analysis system (Merlin image analysis system) measures stain removal
on technical stain swatches. The system utilizes a video camera to acquire color images
of swatches. An image of the swatch is taken before and after it is washed. The acquired
image is then analyzed by computer software (Global R&D computing). The software compares
the unwashed stain to the washed stain, as well as the unwashed fabric to the washed
fabric and produces five figures of merit which describe stain removal. The data are
then analyzed statistically to determine statistically significant differences between
the detergent performances.
[0077] The stain removal index uses the initial fabric as the reference against which to
measure color differences between unwashed and washed stains. A higher value indicates
a better cleaning and stain removal thus a better detergent. The standard deviation
is 1.
| |
Stain Removal Index |
Stain Removal Index |
| Nil Chelant |
54.6 |
22.8 |
| |
|
|
| Chelant |
Wine |
Tea |
| Na-DTPA - 1ppm |
55.2 |
27.6 |
| Na-DTPA - 2 ppm |
55.8 |
29.0 |
| Na-DTPA - 3 ppm |
56.4 |
27.1 |
| Na-EDDS - 1 ppm |
58.3 |
28.2 |
| Na-EDDS - 2 ppm |
59.0 |
29.3 |
| Na-EDDS - 3 ppm |
56.8 |
26.1 |
| Na-DTPA(0.5ppm) |
57.1 |
28.7 |
| Na-EDDS (0.5 ppm) |
|
|
| Na-DTPA (1ppm) |
58.9 |
32.4 |
| Na-EDDS (1ppm) |
|
|
| Na-DTPA (1.5 ppm) |
59.9 |
33.9 |
| Na-EDDS (1.5 ppm) |
|
|
Product stability:
[0078] Products (I through III) were prepared by combining Composition C and the 3 different
chelant combinations. The products (75g) were stored for 4 weeks at 4°C, 20°C and
35°C in a Glass Jar (100mL contenance). The product stability was then assessed visually.
If there is a visual precipitate or a product phase split, the stability is considered
Fail. Stability is considered Pass if there is no signs of changes during the storage
period.
| |
Composition C |
| Ingredient Name |
WT% |
| |
|
| Linear Alkyl benzene sulfonic acid |
16 |
| C12-14 alkyl ethoxy 3 sulfate MEA salt |
10 |
| C12-14 alkyl 7-ethoxylate |
9 |
| C12-18 Fatty acid |
15 |
| Enzymes |
2.3 |
| Solvent |
15 |
| Monoethanol amine |
To pH 7.5 |
| Water |
10 |
| Miscellaneous/Minors |
to 100 |
| |
| Product |
Chelant |
Pass/Fail |
| I |
Na-DTPA - 0.7% |
Pass |
| II |
Na-DTPA - 1.4% |
Fail |
| III |
Na-EDDS/Na-DTPA (0.7%/0.7 %) |
Pass |
[0079] The stability test shows the synenergy between the chelants DTPA and EDDS. A compact
liquid detergent composition comprising 0.7% of Na-DTPA is stable, however it does
not provide desired cleaning efficacy. By increasing the quantity of Na-DTPA to the
effective level, the composition does not meet the stability requirements. Combination
of 0.7% Na-EDDS and 0.7% Na-DTPA does provide desired cleaning efficacy and meets
the stability requirements.
[0080] The dimensions and values disclosed herein are not to be understood as being strictly
limited to the exact numerical values recited. Instead, unless otherwise specified,
each such dimension is intended to mean both the recited value and a functionally
equivalent range surrounding that value. For example, a dimension disclosed as "40
mm" is intended to mean "about 40 mm".