FABRIC SOFTENING LAUNDRY DETERGENTS WITH GOOD STABILITY

FIELD OF THE INVENTION

The present invention relates to the field of liquid laundry detergent compositions that provide fabric softening benefits when utilized in a standard consumer laundry washing machine.

BACKGROUND OF THE INVENTION

Numerous aqueous liquid laundry detergent products are commercially available for the laundering of textiles (e.g. bedding, linens, and/or clothing). These products have traditionally focused on stain-removal and cleaning benefits and could be used in laundry washing machines and/or hand-washing applications. Aqueous laundry detergent compositions are therefore well known in the art and often contain surfactants such as anionic and nonionic surfactants.

More recently, such laundry detergent compositions have been formulated with the inclusion of softness technology, such as cationic cosurfactants (e.g. dodecyltrimethylammonium chloride) or quaternized polymers (e.g. cationic hydroxyethycelluloses), to provide consumers with both cleaning and softness benefits through the wash. Importantly, these formulations allow consumers to avoid utilizing a separate rinse-cycle only fabric enhancer product. Such formulations have become increasingly more desirable to consumers and global rollout of these types of formulations to all markets is therefore desirable. However, in formulating liquid "cleaning plus softness" laundry detergent formulations for the Japanese washing machine conditions, several problems have been recognized.

First, cationic cosurfactant softening compounds are effective, but are expensive. Therefore there is a need for less-expensive materials so that consumer- affordable formulations can be created.

Secondly, quaternized polymer softening compounds can be used as a lower-cost alternative for the cationic cosurfactants, however, they cannot wholly replace cationic cosurfactants so both must be used to provide appropriate through-the-wash softness. The incorporation of both of these types of softening compounds into a single formulation presents a new challenge for stabilizing the overall formulation.

It is believed that by incorporating soap into the detergent formulation that both the cationic cosurfactant and quaternized polymer may be complexed with the soap, promoting codeposition of both softening compounds and thereby enhancing softness.

However, a high level of hydrotrope is typically needed to provide appropriate freeze- thaw stability for the Japan market and a high level of nonionic surfactant is typically needed to provide good cleaning. It has been surprisingly discovered that such hydrotrope and/or nonionic surfactant levels unfortunately can disrupt the softness levels maintained by the soap.

It is therefore desirable to formulate a detergent composition with improved cost structure, softness benefits and stability while maintaining good cleaning, in a single, stable, aqueous laundry detergent composition.

SUMMARY OF THE INVENTION

The present invention encompasses aqueous laundry detergent compositions in the form of a liquid or gel, having a pH of from about 6 to about 11 in a 1% water solution, containing: a) from about 5% to about 15%, by weight of the composition, of a non-soap anionic surfactant; b) from about 0.5% to about 20%, by weight of the composition, of soap; c) from about 0.5% to about 30%, by weight of the composition, of a nonionic surfactant; d) from about 0.2% to about 6%, by weight of the composition, of a fabric softening cationic cosurfactant having a molecular weight of less than about 1000; e) from about 0.05% to about 1%, by weight of the composition, of a fabric softening quaternized polymer having a molecular weight of at least 100,000; f) from about 0.05% to about 0.5%, by weight of the composition, of a non-quaternized, non polyamine thickener; g) from 0% to about 1%, by weight of the composition, of perfume microcapsules; wherein at least one of the following is true; i) the ratio by weight of nonionic surfactant to anionic surfactant is greater than 1 and the total percentage, by weight of the composition, of the total of anionic surfactant, nonionic surfactant and soap is from 10% to 30%; ii) the aqueous laundry detergent composition further comprises from about 0.5% to about 5% of a hydrotrope.

The present invention further encompasses the compositions above wherein the composition has a pH of from about 7.5 to about 9.5.

The present invention further encompasses the compositions above wherein the composition comprises from about 6% to about 10%, by weight of the composition, of the nonsoap anionic surfactant.

The present invention further encompasses the compositions above wherein the nonsoap anionic surfactant is selected from linear alkylbenzenesulfonates, branched alkylbenzenesulfonates, alkylpoly(ethoxylates), alkyl sulfates, methyl ester sulfonates, and mixtures thereof.

The present invention further encompasses the compositions above wherein the composition comprises from about 4% to about 10%, by weight of the composition, of the soap.

The present invention further encompasses the compositions above wherein the soap is selected from oleic acid soaps, palmitic acid soaps, palm kernel fatty acid soaps, and mixtures thereof.

The present invention further encompasses the compositions above wherein the ratio of nonionic surfactant to nonsoap anionic surfactant is at least 1:1.

The present invention further encompasses the compositions above wherein the composition comprises from 0.5% to about 5%, by weight of the composition, of the hydrotrope.

The present invention further encompasses the compositions above wherein the hydrotrope is selected from sodium salt, potassium salt, alkanolammonium salt and acid forms of cumene sulfonic acid, toluene sulfonic acid, xylenesulfonic acid and mixtures thereof.

The present invention further encompasses the compositions above wherein the molecular weight of the fabric softening cationic cosurfactant is less than 300.

The present invention further encompasses the compositions above wherein the fabric softening cationic cosurfactant is water-soluble and comprises one quaternized nitrogen atom.

The present invention further encompasses the compositions above wherein the fabric softening cationic cosurfactant further comprises one long-chain hydrocarbyl group.

The present invention further encompasses the compositions above wherein the fabric softening cationic cosurfactant is selected from water-soluble alkyltrimethylammonium salts or their hydroxyalkyl substituted analogs.

The present invention further encompasses the compositions above wherein the fabric softening cationic cosurfactant is selected from compounds having the formula RχR2R3R4N ⁺ X ^" wherein R^ is a Cg-Cχg alkyl, each of R2, R3 and R4 is independently selected from C1-C4 alkyl, C1-C4 hydroxy alkyl, benzyl, and -(C2H4θ) _x H where x has a value from 2 to 5, and X is an anion; and wherein not more than one of R2, R3 or R4 is benzyl.

The present invention further encompasses the compositions above wherein the fabric softening cationic cosurfactant is dodecyltrimethylammonium chloride.

The present invention further encompasses the compositions above wherein the fabric softening quaternized polymer is a naturally derived hydroxyl-substituted derivative.

The present invention further encompasses the compositions above wherein the fabric softening quaternized polymer is cationic hydroxyethylcellulose.

The present invention further encompasses the compositions above wherein the non- quaternized, non polyamine thickener is selected from methylcellulose, hydroxypropylmethylcellulose, xantham gum, gellan gum, guar gum, hydroxypropyl guar gum, succinoglycan, trihydroxystearin, castor oil, hydrogenated castor oil, hydrogenated castor wax, and mixtures thereof.

The present invention further encompasses the compositions above wherein the composition further comprises a laundry adjunct selected from enzyme stabilizers, dyes, brighteners, opacifiers, deposition aids, pearlescent agents, perfume microcapsules, and mixtures thereof.

The present invention further encompasses aqueous laundry detergent compositions in the form of a liquid or gel, having a pH of from about 6 to about 11 in a 1% water solution, containing: a) from about 5% to about 15%, by weight of the composition, of a non-soap anionic surfactant; b) from about 1% to about 15%, by weight of the composition, of soap; c) from about 0.5% to about 30%, by weight of the composition, of a nonionic surfactant; d) from 0.5% to about 5%, by weight of the composition, of a hydrotrope; e) from about 0.5% to about 5%, by weight of the composition, of a fabric softening cationic cosurfactant selected from dodecyltrimethylammonium chloride; f) from about 0.05% to about 1%, by weight of the composition, of a fabric softening quaternized polymer having a molecular weight of at least 400,000; g) from about 0.05% to about 0.5%, by weight of the composition, of a non-quaternized, non polyamine thickener selected from hydroxypropylmethylcellulose, methylcellulose and mixtures thereof; and h) from 0.001% to about 0.5%, by weight of the composition, of perfume microcapsules; wherein at least one of the following is true; i) the ratio by weight of nonionic surfactant to anionic surfactant is greater than 1 and the total percentage, by weight of the composition, of the total of anionic surfactant, nonionic surfactant and soap is from 10% to 30%;

ii) the aqueous laundry detergent composition further comprises from about 0.5% to about 5% of a hydrotrope.

The present invention further encompasses methods of cleaning and softening textiles, wherein said method comprises the steps of adding the textiles and a sufficient amount of the laundry composition of above to the drum of a standard consumer laundry washing machine and then actuating the washing machine to operate a normal consumer laundry wash cycle.

DETAILED DESCRIPTION OF THE INVENTION

It has now been surprisingly found that by selecting the correct levels of anionic surfactant, nonionic surfactant, soap, hydrotrope, fabric softening cationic cosurfactant, fabric softening quaternized polymer and combining to form an aqueous laundry detergent composition, that a cost-effective, stable aqueous laundry detergent may be formulated. Furthermore, stability and cost-effectiveness is achieved while maintaining good cleaning and softening properties. Therefore, the detergent compositions provided herein are economical, provide good cleaning, and fabric softening, and are capable of meeting the stringent storage testing conditions (including freeze-thaw testing) required for laundry detergents to be marketable in Japan.

The aqueous laundry detergent compositions herein have a pH of from about 6 to about 11 in a 1% aqueous solution, and contain a fabric softening quaternized polymer, a fabric softening cationic cosurfactant, an anionic surfactant, a nonionic surfactant, and, either a high ratio of nonionic surfactant to anionic surfactant or a high level of hydrotrope. Each of these components as well as optional ingredients for such compositions and methods of preparing and using such compositions are described in detail as follows.

All measurements referenced herein are at room temperature (about 21.1 ⁰ C) and at atmospheric pressure, unless otherwise indicated.

The compositions of the present invention can include, consist essentially of, or consist of, the components of the present invention as well as other ingredients described herein. As used herein, "consisting essentially of" means that the composition or component may include additional ingredients, but only if the additional ingredients do not materially alter the basic and novel characteristics of the claimed compositions or methods.

All percentages, parts and ratios are based upon the total weight of the liquid laundry detergent compositions of the present invention, unless otherwise specified. All such weights as they pertain to listed ingredients are based on the active level and, therefore, do not include

carriers or by-products that may be included in commercially available materials, unless otherwise specified.

All documents cited are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention.

Aqueous laundry detergent composition

The compositions of the present invention are aqueous, meaning that they contain at least 5 % water. Other types of water-miscible liquids, such alkanols, diols, other polyols, ethers, amines, and the like, can be added to liquid detergent compositions as co-solvents or stabilizers. However, these other liquids are often more costly. The aqueous laundry compositions of the present invention may be in the form of a liquid or gel. In one embodiment, the compositions comprise from about 30% to 70%, alternatively 35% to 50%, still alternatively from about 10% to 25%, by weight of the composition, of water.

The laundry detergent compositions herein have a pH of from about 6 to about 11 in a 1% solution in water. Preferably, the pH is from about 7.5 to about 9.

Fabric Softening Quaternized Polymer

The aqueous detergent compositions of the present invention contain from about 0.05% to about 1%, alternatively from about 0.1% to about 0.3%, by weight of the composition, of a fabric softening quaternized polymer having a molecular weight of at least 100,000. In one embodiment, the fabric softening quaternized polymer has a molecular weight of greater than 200,000, alternatively greater than 400,000.

In one embodiment, the fabric softening quaternized polymer is cationic hydroxyethylcellulose. Without being limited by theory, some consumers, especially Japanese consumers prefer detergent compositions containing naturally derived materials such as cationic hydroxyethylcellulose. However, synthetic materials (such as PAM/MAPTAC) could be used in the alternative, provided they have suitable molecular weight.

Other fabric softening quaternized polymers useful herein include any of the known Polyquaterniums provided that (a) they are selected to respect the molecular weight requirement and (b) that polyethyleneimine having molecular weight of 25,000 or above is excluded as the fabric softening quaternized polymer (it has been discovered that polyethyleneimine in

combination with high molecular weight fabric softening quaternized polymers may result in precipitate formation leading to an undesirable formulation).

In one embodiment, the fabric softening quaternized polymer is a naturally derived hydroxyl-substituted derivative such as any cationic polyhydroxy compounds which can be derived from starches or gums.

Fabric Softening Cationic Cosurfactant

The aqueous laundry detergent compositions herein contain from about 0.2% to about 6%, by weight of the composition, of a fabric softening cationic cosurfactant having a molecular weight of less than about 1000. In one embodiment, the fabric softening cationic cosurfactant has a molecular weight of less than about 600, alternatively less than about 300; alternatively still, less than 200.

In one embodiment, the composition contains from about 1% to about 4%, alternatively from about 1% to about 3%, by weight of the composition, of the fabric softening cationic cosurfactant.

In one embodiment, the ratio of anionic surfactant to fabric softening cationic cosurfactant is from about 3:1 to about 20:1.

Although not preferred, it is possible herein to utilize an amine oxide such as dodecyldimethylamine-N-oxide for the fabric softening cationic cosurfactant. This is especially a selection in lower pH detergent embodiments within the range of pH from about 6 to about 8.5. Without being limited by theory, as the pH decreases, increasing proportions of the amine oxide become protonated and the amine oxide behaves as a substitute for the permanently cationic cosurfactant.

In one embodiment, the fabric softening cationic cosurfactant is water-soluble and comprises no more than four quaternized nitrogen atoms.

In one embodiment the fabric softening cationic cosurfactant contains less than 10 ppm of trimethylamine and/or dimethylamine impurities, more preferably less than 2ppm. Without being limited by theory, compositions containing greater than lOppm of trimethylamine and/or dimethyalmine will have poor odor quality.

In one embodiment, the fabric softening cationic cosurfactant is water-soluble and comprises one quaternized nitrogen atom, and further contains one long-chain hydrocarbyl group. In another embodiment, the fabric softening cationic cosurfactant is selected from water- soluble alkyltrimethylammonium salts or their hydroxyalkyl substituted analogs.

In one embodiment, the fabric softening cationic cosurfactant is selected from compounds having the formula RχR2R3R4N ⁺ X ^" wherein R^ is a Cg-Cχg alkyl, each of R2, R3 and R4 is independently selected from C1-C4 alkyl, C1-C4 hydroxy alkyl, benzyl, and -(C2H4θ) _x H where x has a value from 2 to 5, and X is an anion; and wherein not more than one of R2, R3 or R4 is benzyl.

In a preferred embodiment, the fabric softening cationic cosurfactant is dodecyltrimethylammonium chloride although alternately bromide, methosulfate or other water- soluble anions can be used as replacements for chloride.

Thickener

The aqueous detergent compositions of the present invention contain from about 0.05% to about 0.5%, by weight of the composition, of a non-quaternized, non polyamine thickener. Thickeners useful herein include rheology modifiers, structurants and combinations thereof.

Structurants useful herein include methylcellulose, hydroxypropylmethylcellulose such as METHOCEL® trade name from Dow Chemical, xanthan gum, gellan gum, guar gum, hydroxypropyl guar gum, succinoglycan and trihydroxystearin. Other illustrative examples of structurants includes the nonpolymeric hydroxyfunctional structurants. Without being limited by theory, a structurant is incorporated into a detergent composition to establish desired rheological characteristics in a liquid product.

Other structurants useful herein include non-polymeric, crystalline hydroxy-functional materials which can form thread-like structuring systems throughout the liquid matrix when they are crystallized within the matrix in situ. Such materials can be generally characterized as crystalline, hydroxyl-containing fatty acids, fatty esters or fatty waxes. Examples of hydroxyl- containing structurants include castor oil and its derivatives. More specifically, useful herein are hydrogenated castor oil derivatives such as hydrogenated castor oil and hydrogenated castor wax. Commercially available, castor oil-based, crystalline, hydroxyl-containing structurants include

THIXCIN® from Rheox, Inc. See also U.S. Patent No. 6,080,708 and PCT Publication No. WO 02/40627. Another commercially available structurant is 1 ,4-di-O-benzyl-D-Threitol in the R,R, and S, S forms and any mixtures, optically active or not.

The structurant or thickener herein is preferably not hydrolysed, however for avoidance of doubt, the detergent compositions herein may contain fatty acids or fatty soaps derived from hydrolysis of the thickener, such as various hydroxystearic acids or their salts.

In one embodiment, the non-quaternized, non polyamine thickener is selected from methylcellulose, hydroxypropylmethylcellulose, xantham gum, gellan gum, guar gum, hydroxypropyl guar gum, succinoglycan, trihydroxystearin, castor oil, hydrogenated castor oil, hydrogenated castor wax, and mixtures thereof.

Anionic Surfactant

The aqueous laundry detergent compositions herein contain an anionic surfactant. Any non-soap anionic surfactant known in the art for use in laundry detergents may be utilized. The compositions contain from about 5% to about 15%, by weight of the composition, of the non- soap anionic surfactant. In one embodiment, the composition contains from about 6% to about 15%, alternatively from about 6% to about 8%, by weight of the composition, of the non-soap anionic surfactant.

In one embodiment, the anionic surfactant is selected from linear alkylbenzenesulfonates, branched alkylbenzenesulfonates, alkylpoly(ethoxylates), alkyl sulfates, methyl ester sulfonates, and mixtures thereof. The Hydrophilicity Index of the anionic surfactant may vary widely.

Examples of anionic surfactants useful herein include any of the common anionic surfactants such as linear or modified, e.g., branched, alkylbenzenesulfonate surfactants, alkylpoly(ethoxylate) surfactants, alkyl sulfates, methyl ester sulfonates, or mixtures thereof. Generally speaking, anionic surfactants useful herein are disclosed in U.S. Patent No. 4,285,841, Barrat et al., issued August 25, 1981, and in U.S. Patent No. 3,919,678, Laughlin, et al., issued December 30, 1975.

Useful anionic surfactants include the water-soluble salts, particularly the alkali metal, ammonium and alkylolammonium (e.g., monoethanolammonium or triethanolammonium) salts, of organic sulfuric reaction products having in their molecular structure an alkyl group containing from about 10 to about 20 carbon atoms and a sulfonic acid or sulfuric acid ester group. (Included in the term "alkyl" is the alkyl portion of aryl groups.) Examples of this group of synthetic surfactants are the alkyl sulfates, especially those obtained by sulfating the higher alcohols (C _8-I8 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil.

Other anionic surfactants herein are the water-soluble salts of: paraffin sulfonates containing from about 8 to about 24 (preferably about 12 to 18) carbon atoms; alkyl glyceryl ether sulfonates, especially those ethers of Cs-is alcohols (e.g., those derived from tallow and coconut oil); alkyl phenol ethylene oxide ether sulfates containing from about 1 to about 4 units

of ethylene oxide per molecule and from about 8 to about 12 carbon atoms in the alkyl group; and alkyl ethylene oxide ether sulfates containing about 1 to about 4 units of ethylene oxide per molecule and from about 10 to about 20 carbon atoms in the alkyl group.

Other useful anionic surfactants herein include the water-soluble salts of esters of α- sulfonated fatty acids containing from about 6 to 20 carbon atoms in the fatty acid group and from about 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxy-alkane-l- sulfonic acids containing from about 2 to 9 carbon atoms in the acyl group and from about 9 to about 23 carbon atoms in the alkane moiety; water-soluble salts of olefin sulfonates containing from about 12 to 24 carbon atoms; and β-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group and from about 8 to 20 carbon atoms in the alkane moiety.

Particularly preferred anionic surfactants herein are the alkyl polyethoxylate sulfates of the formula:

RO(C ₂ H ₄ O) _x SO ₃ M ⁺ wherein R is an alkyl chain having from about 10 to about 22 carbon atoms, saturated or unsaturated, and the longest linear portion of the alkyl chain is 15 carbon atoms or less on the average, M is a cation which makes the compound water-soluble, especially an alkali metal, ammonium or substituted ammonium cation, and x is from 1 to about 15.

Other preferred anionic surfactants are the non-ethoxylated Ci _2-I5 primary and secondary alkyl sulfates. Under cold water washing conditions, i.e., less than about 65° F. (18.3°C), it is preferred that there be a mixture of such ethoxylated and non-ethoxylated alkyl sulfates.

Mixtures of the alkyl sulfates with the above-described paraffin sulfonates, alkyl glyceryl ether sulfonates and esters of α-sulfonated fatty acids, are also preferred.

The anionic surfactant may also be selected from alkyl benzene sulfonates. In one embodiment, the composition comprises less than 6%, by weight of the composition, of alkyl benzene sulfonates. These include alkylbenzene sulfonates in which the alkyl group contains from about 9 to about 15 carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in U.S. Patent No. 2,220,099 and No. 2,477,383.

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The aqueous laundry detergent compositions herein may contain soap. While the invention includes embodiments having no soap, preferred embodiments include soap. Without being limited by theory, it may be desirable to include soap as it acts in part as a surfactant and in part as a builder and may also be useful for suppression of foam. Moreover, without being

limited by theory, the soap may interact favorably with the various cationic compounds of the composition to enhance softness on textile fabrics treated with the inventive compositions. Any soap known in the art for use in laundry detergents may be utilized. In one embodiment, the compositions contain from 0% to about 20%, alternatively from about 0.5% to about 20%, alternatively from about 4% to about 10%, alternatively from about 4% to about 7%, by weight of the composition, of soap.

Examples of soap useful herein include oleic acid soaps, palmitic acid soaps, palm kernel fatty acid soaps, and mixtures thereof. Typical soaps are in the form of mixtures of fatty acid soaps having different chainlengths and degrees of substitution. One such mixture is topped palm kernel fatty acid.

In one embodiment, the soap is selected from free fatty acid. Suitable fatty acids are saturated and/or unsaturated and can be obtained from natural sources such a plant or animal esters (e.g., palm kernel oil, palm oil, coconut oil, babassu oil, safflower oil, tall oil, castor oil, tallow and fish oils, grease, and mixtures thereof), or synthetically prepared (e.g., via the oxidation of petroleum or by hydrogenation of carbon monoxide via the Fisher Tropsch process). Examples of suitable saturated fatty acids for use in the compositions of this invention include captic, lauric, myristic, palmitic, stearic, arachidic and behenic acid. Suitable unsaturated fatty acid species include: palmitoleic, oleic, linoleic, linolenic and ricinoleic acid. Examples of preferred fatty acids are saturated Cn fatty acid, saturated Ci ₂ -Ci ₄ fatty acids, and saturated or unsaturated Cn to Ci ₈ fatty acids, and mixtures thereof.

When present, the weight ratio of fabric softening cationic cosurfactant to fatty acid is preferably from about 1:3 to about 3: 1, more preferably from about 1:1.5 to about 1.5:1, most preferably about 1:1.

Levels of soap and of nonsoap anionic surfactants herein are percentages by weight of the detergent composition, specified on an acid form basis. However, as is commonly understood in the art, anionic surfactants and soaps are in practice neutralized using sodium, potassium or alkanolammonium bases, such as sodium hydroxide or monoethanolamine.

Nonionic Surfactant

The aqueous laundry detergent compositions herein contain a nonionic surfactant. Any nonionic surfactant known in the art for use in laundry detergents may be utilized. The compositions contain from about 0.5% to about 30%, by weight of the composition, of the nonionic surfactant. In one embodiment, the composition contains from about 5% to about 15%,

alternatively from about 8% to about 12%, by weight of the composition, of the nonionic surfactant.

In one embodiment, the ratio of anionic surfactant to nonionic surfactant is equal to or greater than 1.

Examples of nonionic surfactants useful herein include long-chain alkyl poly(ethoxylates), such as C12-C16(EO)xH where EO represents ethylene oxide and x can range from 1 to 8.

Other examples of nonionic surfactants useful herein include ethoxylated nonionic surfactants. These materials are described in U.S. Pat. No. 4,285,841, Barrat et al, issued Aug. 25, 1981. In one embodiment, the nonionic surfactant is selected from the ethoxylated alcohols and ethoxylated alkyl phenols of the formula R(OC ₂ H ₄ ) _n OH, wherein R is selected from the group consisting of aliphatic hydrocarbon radicals containing from about 8 to about 15 carbon atoms and alkyl phenyl radicals in which the alkyl groups contain from about 8 to about 12 carbon atoms, and the average value of n is from about 5 to about 15. These surfactants are more fully described in U.S. Pat. No. 4,284,532, Leikhim et al, issued Aug. 18, 1981. In one embodiment, the nonionic surfactant is selected from ethoxylated alcohols having an average of from about 10 to about 15 carbon atoms in the alcohol and an average degree of ethoxylation of from about 6 to about 12 moles of ethylene oxide per mole of alcohol.

Hydrotrope

The aqueous laundry detergent compositions herein may contain a hydrotrope. In one embodiment, the composition contains from 0% to about 5%, by weight of the composition, of a hydrotrope, alternatively from about 0.5% to about 5%, alternatively from about 3% to about 5%, of a hydrotrope. Any hydrotrope known in the art for use in laundry detergents may be utilized.

Examples of hydrotropes useful herein include sodium salt, potassium salt, alkanolammonium salt and acid forms of cumene sulfonic acid, toluene sulfonic acid, xylenesulfonic acid and mixtures thereof.

Without being limited by theory, it is desirable to utilize a hydrotrope since it avoids over-thickening of the formulation and can improve freeze-thaw stability under Japanese testing conditions. In one embodiment, the viscosity of the aqueous laundry detergent is independently controlled by utilization of a hydrotrope and a non-cationic thickener.

Perfumes and perfume microcapsules

The aqueous laundry detergent compositions herein may contain perfumes. The perfume ingredients may be premixed to form a perfume accord prior to adding to the detergent compositions. As used herein, the term "perfume" encompasses individual perfume ingredients as well as perfume accords. In one embodiment, the compositions of the present invention comprise perfume microcapsules. Varying proportions of perfume in microcapsule form and non- microcapsule, i.e., "free" form can be mixed into the aqueous liquid laundry detergent compositions.

Perfume microcapsules comprise perfume raw materials contained within a capsule. Suitable encapsulates can be aminoplasts or non-aminoplasts. Encapsulates can be made of materials selected from the group consisting of urea and formaldehyde, melamine and formaldehyde, phenol and formaldehyde, gelatine, polyurethane, polyamides, cellulose ethers, cellulose esters, polymethacrylate and mixtures thereof. Encapsulation techniques can be found in "Microencapsulation: methods and industrial applications" edited by Benita and Simon (marcel Dekker Inc 1996).

The level of perfume accord in the detergent composition is typically from about 0.0001% to about 2% or higher, e.g., to about 10%. In one embodiment, the level of perfume accord is from about 0.0002% to about 0.8%, alternatively from about 0.003% to about 0.6%, alternatively from about 0.005% to about 0.5%, by weight of the detergent composition.

When perfume microcapsules are used, the total amount of perfume microcapsule is from about 0.001% to about 0.5%, alternately from about 0.01% to 0.2%, by weight of the composition. When formulating perfume microcapsules, it is known to use thickeners or structurants such as trihydroxystearin, to suspend the microcapsules stably in the liquid detergent. Suitable perfume microcapsules for use herein are disclosed PCT Applications: WO 08/016684A1 (Procter & Gamble); WO 08/016637A1 (Procter & Gamble); WO 08/016637A1 (Appleton); WO07/137441A1 (Givaudan); WO 07/096790A1; WO 07/004166Al; WO 06/131846A1; WO06/018694A1; and WO 05/017085A1 (Firmenich); and WO 07/062833A1 (Unilever). More generally, as taught in WO 08/016684A1, the perfume microcapsules can be replaced in whole or in part by a benefit agent containing delivery particle as described therein.

The level of perfume ingredients in the perfume accord is typically from about 0.0001% (more preferably 0.01%) to about 99%, preferably from about 0.01% to about 50%, more preferably from about 0.2% to about 30%, even more preferably from about 1% to about 20%, most preferably from about 2% to about 10% by weight of the perfume accord. Exemplary

perfume ingredients and perfume accords are disclosed in U.S. Pat. 5,445,747; U.S. Pat. 5,500,138; U.S. Pat. 5,531,910; U.S. Pat. 6,491,840; and U.S. Pat. 6,903,061.

pH Adjustment

Neutralizers and buffers may be used to reach the targeted composition pH. Sodium, potassium and alkanolamines may utilized as neutralizers. Borate or other buffers, or borate- polyol pH jump systems can likewise be utilized herein.

Optional Components

The detergent compositions of the present invention can also include any number of additional optional ingredients. These include conventional laundry detergent composition components such as pearlescent agents, perfumes, perfume deposition aids, deposition aids, detersive builders, enzymes, enzyme stabilizers (such as propylene glycol, boric acid and/or borax), suds suppressors, soil suspending agents, soil release agents, other fabric care benefit agents, pH adjusting agents, chelating agents, smectite clays, solvents, phase stabilizers, structuring agents, dye transfer inhibiting agents, optical brighteners, perfumes, perfume microcapsules, dyes, and coloring agents. The various optional detergent composition ingredients, if present in the compositions herein, should be utilized at concentrations conventionally employed to bring about their desired contribution to the composition or the laundering operation. Frequently, the total amount of such optional detergent composition ingredients can range from about 10% to about 50%, more preferably from about 30% to about 40%, by weight of the composition.

Product Form

The aqueous laundry detergent compositions herein can be clear or hazy, they do not need to be optically isotropic. For avoidance of confusion, haze or opacity does not constitute instability in the product provided that no solids deposit on storage (including freeze-thaw testing).

Stability

Without being limited by theory, it is believed that the liquid detergent compositions of the invention are remarkably stable, even under freeze-thaw testing conditions.

Use of the composition in domestic laundry washing machines

The present compositions can be used in domestic laundry washing machines, at typical dosages of from about 20 millilitres to about 130 millilitres, depending on the size of the washing machine, the level of soiling, and the geography of use, since washing machines are adapted for different countries. For use in Japanese washing machines, a typical dose is from about 20 millilitres to about 40 millilitres. The compositions can be used in top-loading or in horizontal or inclined axis washers.

EXAMPLES

The following examples illustrate the compositions of the present invention but are not necessarily meant to limit or otherwise define the scope of the invention herein.

EXAMPLES IA and IB

Two compositions according to the present invention are prepared by conventional means of combining the ingredients listed in Table I in the proportions shown.

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 include also "about 40 mm."

Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.