IE55427B1

IE55427B1 - Fatty acid containing detergent compositions

Info

Publication number: IE55427B1
Application number: IE1206/83A
Authority: IE
Original assignee: Procter & Gamble
Priority date: 1982-05-24
Filing date: 1983-05-23
Publication date: 1990-09-12
Also published as: ATE22920T1; MX162610A; EP0095205A1; FI73727C; AU559791B2; FI831832L; IE831206L; GR78820B; EP0095205B1; FI831832A0; JPH0477038B2; JPS5925894A; CA1208519A; DE3366958D1; AU1488883A; FI73727B

Abstract

Detergent compositions, preferably heavy-duty liquids, containing an anionic surfactant, a selected cosurfactant and a fatty acid are disclosed. The compositions are formulated to provide an initial pH of from about 6.0 to about 8.5 at a concentration of from about 0.1% to about 2% by weight in water at 20 DEG C. The compositions preferably also contain ethoxylated nonionic surfactants, a detergent builder and enzymes.

Description

2 2 5¾ 4 Z~< The present invention relates to detergent compositions, preferably liquid detergents, containing an anionic synthetic surfactant, a cosurfactant selected from certain quaternary ammonium, diquaternary ammonium, amine b ana diamine surfactants, and a fatty acid. The compositions herein have a molar ratio of the anionic synthetic surfactant to the cosurfactant of at least 1 and are formulated to provide an initial pH of from 6.0 to 8.5 at a concentration of from 0.1% to 2% by weight in 10 water at 20°C. The compositions provide both superior greasy/ oily soil removal and good builder/pH sensitive soil removal at the near-neutral wash pH.

U.S. Patent 4,285,841, Barrat et al_, issued August 25, 1981 , discloses liquid detergents containing anionic surfactants, nonionic 15 surfactants and from about 8% to about 20% by weight of a fatty acid. The compositions have a pH of from about 6.0 to 7.5.

U.S. Patent 4,287,082, Toifo et_al, issued September 1, 1981, discloses liquid detergents containing saturated fatty acids, enzymes, enzyme-accessible calcium and selected short-chain 2u carboxylic acids.

U.S. Patent 4,321,165, Smith et. at., issued March 23, 1982, discloses built detergents containing anionic, nonionic and cationic surfactants. The compositions provide a solution pH of at least about 6, and preferably greater than about 8.

The present invention encompasses detergent compositions comprising: (a) from 2% to 60% by weight of an anionic synthetic surfactant; (b) from 0.25% to 12% by weight of a cosur- 30 factant selected from: 3 (i) quaternary ammonium surfactants having the formula: [R2(OR3) l[R4(OR3) 1,RSN+X" 2 y y * wherein R is an alkyl or alkyl benzyl group having from 8 5 to 18 carbon atoms in the alkyl chain; each R3 is selected from -CH2CH2t, -CH2CH(CH3)-, -CH2CH(CH2OH)-, -CK2CH2CH2" and mixtures thereof; each R4 is selected from hydrogen (provided that y is not 0), C1-4 alkyl, hydr- oxyalkyl, benzyl, ring structures formed by joining the two 10 R4 groups. and -CH2C3JCHCHOHCDR^CHCHCU2OH wherein R*’ is any hexose or hexose polymer having a molecular weight up to 5 4 1000; R is the same as R or is 2 an alkyl chain wherein the total number of carbon atoms of R plus R5 is not more than 18; each y is from 0 to 10 15 and the sum of the y values is from 0 to 15; and X is any compatible anion; (ii) diquaternary ammonium surfactants having the formula: [ R2(OR3) ] [R4(OR3) ]-N+R3N+R3[ R4(OR3) ], (X')2 20 wherein R , R , R , R , y and X are as defined above; (iii) amine surfactants having the formula: [R2(OR3) l[R4(OR3) 1RSN 2 3iiS' / wherein R , R , R , R and y are as defined above; and (iv) diamine surfactants having the formula: 25 [R2(OR3) 1[r"(OR3) 1NR3NR5[r\0R3) ] \2 3 4 y s y wherein R , R , R , R and y are as defined above; and (c) from 5% to 40% by weight of a fatty acid containing from 10 to 22 carbon atoms and from 0 to 10 .ethylene oxide units in the hydrocarbon chain; 4 said composition having a molar ratio of the anionic synthetic surfactant to the cosurfactant of at least 1 and formulated to provide an initial pH of from 6.0 to 8.5 at a concentration of from 0.1% to 2% by weight in water at 20°C.

The detergent compositions herein contain an anionic synthetic surfactant, a cosurfactant selected from certain quaternary ammonium, diquaternary ammonium, amine and diamine surfactants, and a fatty acid material. The compositons can be in any form, including granules, liquids, tablets or pastes. However, liquid compositions are highly preferred since the compositions herein are especially effective when applied directly to soils and stains in a pretreatment step. The compositions herein must have a molar ratio of the anionic synthetic surfactant to the cosurfactant of at least one, preferably from 2:1 to 20:1, and are formulated to provide an initial pH of from 6,0 to 8.5 at a concentration of from 0.1% to 2% by weight in water at 20°C. It has been found that the addition of the cosurfactant to the fatty acid containing detergents herein provides important greasy/oily soil removal benefits only at the near-neutral wash pH. The wash pH is preferably from 7.0 to 8.5, more preferably from 7.5 to 8.0.

While not intending to be limited by theory, it is believed that the cosurfactant and anionic surfactant herein form complexes which enhance packing of the surfactants at the oil/water interface, thereby lowering interfacial tension and improving detergency. (The amine and diamine surfactants would be at least partially protonated at the near-neutral pH and thus can form charged species capable of complex-ing with the anionic surfactant.) At the defined pH range recited herein, the fatty acid component exists in a chemical form which is optimal for effective detergency. At too low a pH, the non-dissociated form of the acid is ineffective, It is also believed that the higher pH's (i.e., above 8.5) affect the interaction 5 of the fatty acid with the cosurfactant and water hardness and result in the formation of undesirable species at the oil/water interface which reduce detergency performance.

Anionic Synthetic Surfactant 5 The detergent compositions herein contain from 2% to 60% by weight of an anionic synthetic surfactant, or mixtures thereof. The anionic surfactant preferably represents from 5% to 40%, and more preferably from 10% to 20%, by weight of the detergent composition. Anionic sur-10 factants useful herein are disclosed in U.S. Patent 4,285,841, Barrat _et _al_, issued August 25, 1981, and in U.S. Patent 3,919,678, Lauqhlin et al. issued December 30, 1975.

Useful anionic surfactants include the water-soluble salts, particularly the alkali metal, ammonium and alkylolammonium 15 (e.g., monoethanolammonium or triethanolammonium) 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 aryl groups.) 20 Examples of this group of synthetic surfactants are the alkyl sulfates, especially those obtained by sulfating the higher alcohols (Cg-C|8 carbon atoms) such as those produced by reducing the glycerides of tallow or coconut oil; and the alkylbenzene sulfonates in which the alkyl group contains from 9 to 15 25 carbon atoms, in straight chain or branched chain configuration, e.g., those of the type described in United States 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 14.

Other anionic surfactants herein are the water-soluble salts of; paraffin sulfonates containing from 8 to 24 (pre ferably 12 to 18) carbon atoms; alkyl glyceryl ether sulfonates, especially those ethers of alcohols (e.g., those derived from tallow and coconut oil); alkyl phenol ethylene oxide 8 ether sulfates containing from | to 4 units of ethylene oxide per molecule and from 8 to 12 carbon atoms in the alkyl group; and alkyl ethylene oxide ether sulfates containing 1 to 4 units of ethylene oxide per molecule and from 10 to 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 6 to 20 carbon atoms in the fatty acid group and from 1 to 10 carbon atoms in the ester group; water-soluble salts of 2-acyloxy-alkane-l-sulfonic acids containing from 2 to 9 carbon atoms in the acyl group and from 9 to 23 carbon atoms in the alkane moiety; water-soluble salts of olefin sulfonates containing from I2 to 24 carbon atoms; and B-alkyloxy alkane sulfonates containing from I to 3 carbon atoms in the alkyl group and from 8 to 20 carbon atoms in the alkane moiety.

Particularly preferred anionic surfactants herein are the alkyl sulfates of the formula R0(C2H40)xS03M+ wherein R is an alkyl chain having from 8 to 18 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 0 to 4. Most preferred are the non-ethoxylated ^ primary and secondary alkyl sulfates. Under cold water washing conditions, i.e., less than 65°F (18.3°C), it is preferred that there be a mixture of such alkyl sulfates.

Mixtures of the alkyl sulfates with the above-described alkylbenzene sulfonates, paraffin sulfonates, alkyl glyceryl ether sulfonates and esters of a α-sulfonated fatty acids, particularly with the ^i_i3 l*near alkylbenzene sulfonates, are also preferred.

Cosurfactant 7 The compositions herein also contain from 0.25¾ to 12%, preferably from 0.5% to 8%, more preferably from 1% to 4%, by weight of a cosurfactant selected from certain quarternary ammonium, diquaternary ammonium, amine and diamine surfactants. The quaternary ammonium surfactants are particularly preferred.

The quaternary ammonium surfactants herein are of the formula: [R2(OR3) l[R4(OR3) ],R5N+X" 2 y y L wherein R is an alkyl or alkyl benzyl group having from 8 3 to 18 carbon atoms in the alkyl chain; each R is selected from -CH2CH2-, -CH2CH(CH3)-, -CH2CH(CH2OH)-, -CH2CH2CH2-, and mixtures thereof; each R4 is selected from Ci-4 Ci-4 hydroxy - alkyl, benzyl, ring structures formed by joining the two R4 groups, -CH2CHOHCHOHCOR6CHOHCH2OH wherein R6 is any hexose or hexose polymer having a molecular weight less than 5 4 1000, and hydrogen when y is not 0; R is the same as R or is an alkyl chain wherein the total number of carbon atoms of R2 plus R3 is not more than 18; each y is from 0 to 10 and the sum of the y values is from 0 to 15; and X is any compatible anion.

Preferred of the above are the alkyl quaternary ammonium surfactants, especially the mono-long chain alkyl surfactants 5 described in the above formula when R is selected from the same If groups as R . The most preferred quaternary ammonium surfactants are the chloride, bromide and methylsulfate Cg1(. alkyl trimethylammonium salts, ^8-16 alkyl di(hydroxyethyl)methyiammonium salts, the Cgl(. alkyl hydroxyethyldimethylammonium salts, and Cg alkyloxypropyl trimethylammonium salts. Of the above, decyl trimethylammonium methylsulfate, lauryl trimethylammonium chloride, myristyl trimethylammonium bromide and coconut trimethylammonium chloride and methylsulfate are particularly preferred. 8 Under cold water washing conditions, i.e., less than 65°F (18.3°C), the Cg_^ alkyltrimethyl ammonium surfactants are particularly - preferred since they have a lower Kraft boundry and, therefore, a lower crystallization temperature than the 5 longer alkyl chain quaternary ammonium surfactants herein.

Diquaternary ammonium surfactants herein are of the formula: [R2(OR3] HR^OR3) 1,N+R3N+R5IR4(0R3) 1 (ΧΊ, / ? 3*4 5 * wherein the R , R , R , R , y and X substituents are as defined 10 above for the quaternary ammonium surfactants. These substituents are also preferably selected to provide diquaternary ammonium surfactants corresponding to the preferred quaternary ammonium surfactants. Particularly preferred are the Cg_lg alkyl pentamethylethylenediammonium chloride, bromide and 15 methylsulfate salts.

Amine surfactants useful herein are of the formula: [R2(OR3)v1[R4(OR3) 1R5N 2 3 Ψ 5 ' wherein the R , R , R , R and y substituents are as defined above for the quaternary ammonium surfactants. Particularly 20 preferred are the Cj2-16 dimethyl amines.

Diamine surfactants herein are of the formula [R2[OR3l HrW3)JNRWtR^COR3) 1 y 2 3 y 4 5 y wherein the R , R , R , R and y substituents are as defined above. Preferred are the ^12-16 a'kyl trimethylethylene 25 diamines. 9 Fatty Acid- The compositions of the present invention contain from 5% to 40%, preferably from 7% to 30%, most preferably from 10% to 20%, by weight of a fatty acid 5 containing from 10 to 22 carbon atoms. The fatty acid can also contain from 1 to 10 ethylene oxide units in the hydrocarbon chain.

Suitable fatty acids are saturated and/or unsaturated and can be obtained from natural sources such as plant or animal 10 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 15 fatty acids for use in the compositions of this invention; include capric, lauric, myristic, palmitic, stearic, arachidic and behenic acid. Suitable unsaturated fatty acid species include: palmitoleic, oleic, linoleic, iinolenic and ricinoleic acid. Examples of preferred fatty adds are saturated C^-C^ (coconut) fatty 20 acids, from 5:1 to 1:1 (preferably 3:1 ) weight ratio mixtures of lauric and myristic acid, and mixtures of the above lauric/myristic blends with oleic acid at a weight ratio of 4:1 to 1:4 mixed lauric/myristic : oleic.

Optional Components 25 The compositions of the present invention also preferably contain up to 30%, preferably from 1% to 20%, more preferably from 5% to 15%, by weight of an ethoxylated nonionic surfactant. These materials are described in U.S. Patent 4,285,841 , Barrat et at, issued August 25, 1981. 30 Preferred are the ethoxylated alcohols and ethoxylated alkyl phenols of the formula R(OC2H1()nOH, wherein E is selected from aliphatic hydrocarbon radicals containing from 8 to 15 carbon atoms and alkyl phenyl radicals in which the alkyl groups 35 contain from 8 to 12 carbon atoms, n is from 3 10 to 9, and said nonionic surfactant has an HLB (hydrophile-lipophile balance) value of from 10 to 13. These surfactants are more fully described in U.S. Patent 4,289,532, Leikhim et_jal, issued August 18, 1981.

Particularly preferred are ethoxylated alcohols having an average of from 10 to 15 carbon atoms in the alcohol and an average degree of ethoxylation of from 3 to 8 moles of ethylene oxide per mole of alcohol.

The compositions herein also preferably contain up to 40%, more preferably from 1% to 30%, by weight of a detergent builder material. While all manner of detergent builders known in the art can be used in the present compositions, the type and level of builder must be selected such that the final composition has an initial pH of from 6.0 to 8.5 at a concentration of from 0.1% to 1% by weight in water at 20°C. Detergent builders are described in U.S. Patent 4,321.165, Smith _et _al_, issued March 23, 1982.

In the preferred liquid detergent compositions herein, the builder preferably represents from 1% to 20%, more preferably from 3% to 10%, by weight of the composition. Preferred builders for use in liquid detergents herein are described in U.S. Patent 4,284,532, Leikhim et al, issued August 18, 1981.

A particularly preferred builder is citric acid.

Other preferred components for use in liquid detergents herein are the neutralizing agents, buffering agents, phase regulants, hydrotropes, enzymes, enzyme stabilizing agents, polyacids, suds regulants, opacifiers, antioxidants, bactericides, dyes, perfumes, and brighteners described in the U.S. Patent 4,285,841, Barrat et al, issued August 25, 1981.

Preferred neutralizing agents for use herein are organic bases, especially triethanolamine and monoethanolamine, which result in better detergency performance than inorganic bases such as sodium and potassium hydroxides. 11 Particularly preferred compositions herein contain from 0.1¾ to 2% by weight of detersive enzymes, especially the amylases, proteases, and mixtures thereof, of the type well known to detergent formulators.

The following non-limiting examples illustrate the compositions of the present invention. All percentages, parts and ratios used herein are by weight unless otherwise specified.

EXAMPLE I Four sets of 7.6 cm square polycotton (P/C) or cotton (C) swatches stained with standard soils were washed in an automatic mini-washer using 2000 ppm of either Composition A, a commercially available heavy-duty liquid detergent; Composition B containing, by weight, 6.2¾ sodium C.^ linear alkylbenzene sulfonate, 9.4% sodium alkyl sulfate, 10.0% alcohol polyethoxylate (6.5), 10.0% coconut fatty acid, 5.0% oleic fatty acid, 15.0% citric acid, 0.3% diethylenetriame pentamethylene phosphonic acid, 0.23% brightener, 1.0% protease enzyme, enough monoethanolamine to achieve the desired pH and the balance, to 100% water; Composition C, which was B plus 2.7% by weight of Cjj alkyl trimethylammonium chloride; or Composition D, which was B plus 2.7% by weight of C12_lg alkyl dimethyl amine oxide.

The wash pH was about 7.3 for Composition A and about 7.4 for B, C and D. The wash water temperature was 95°F (35°C) and the water hardness was 86mg/l (5 grains/gallon) (3:1 Ca :Mg ). The swatches were then dried and each set was round robin comparison graded against its counterparts to determine relative soil removal provided by the detergent compositions. A grading scale of -4 to 4 was used, with -4 indicating much less soil removal, 0 indicating no difference and 4 indicating much more soil removal. The results for each composition were then averaged and Composition A was assigned a relative value of 0.

A similar comparision was made except that the wash pH for Compositions B, C and D was about 9.5.

The results were as follows. 12 Wash pH 7,4 Wash pH 9.5 Ccnpcsition Soil Fabric Ξ C D B C D —- "* — — — — — Bacon grease P/C 0.1 1.6 0.9 0.6 0.7 0.5 Synthetic dir- P/C 0.1 1.9 2.6 -0.7 1.0 0.6 ty motor oil Makeup (oil P/C -0.5 1.5 1.6 -2.0 -1.7 -2.6 base) Spaghetti P/C -1.3 -1.7 -1.8 -0.5 -0.7 -0.1 sauce Chocolate C 1.5 1.0 -0.2 -0.4 -2.0 -2.0 Grass P/C -1.6 1.8 2.3 3.5 3.6 4.2 Gravy C 0.9 0.5 1.6 4.0 3.6 3.7 Clay P/C 2.2 3.7 3.3 -1.0 0.9 -0.8 Clay C 3.2 2.9 3.5 4.1 3.6 3.2 Body Soil P/C 0.6 0.4 0.5 0.8 1.3 0.8 The above results demonstrate that Composition C of the present invention containing quaternary ammonium cosurfactant provides important advantages on greasy/oil soils and also on grass and clay (on PC) relative to Composition B at wash pH's of 7.4. However, these advantages are substantially eliminated at wash pH's of 9.5.

As demonstrated above, the present invention also encompasses a method for laundering fabrics comprising contacting said fabrics with an aqueous solution having a pH of from 6.0 to 8.5 at 20°C and containing at least 0.1% by weight of the compositions herein.

EXAMPLE II Liquid detergent compositions of the present invention are as follows.

Component Wt. % A B C^j linear alkylbenzene sulfonic acid 5.8 5.5 Coconutalkyl sulfuric acid 8.8 8.3 Cj2 alkyl trimethylammonium chloride 1.2 C.^ alkyl trimethylammonium bromide - 1.7 C12 13 alcohol polyethoxylate (6.5) 10.0 - C13_l5 alcohol polyethoxylate (7) - 9.4 Laurie acid 7.5 7.1 Myristic acid 2.5 2.3 Oleic acid 5.0 4.7 Citric acid monohydrate Diethylenetriamine pentamethylene- 7.5 5.7 phosphonic acid 0.3 0.3 Diethylenetriamine pentaacetic acid 0.3 0.3 Protease enzyme 1.0 1.0 Amylase enzyme 0.3 0.3 Monoethanolamine 12.0 - T riethanolamine 6.7 7.5 Sodium hydroxide - 3.2 Potassium hydroxide - 4.0 1,2-Propanediol 5.0 8.5 Ethanol 1.0 4.7 Sodium formate 1.0 1.0 Sodium toluene sulfonate 5.0 - Minors and water Balance to 100 k 45% branched Composition A was prepared by adding the components, with continuous mixing, in the following order: alcohol polyethoxylate; monoethanolamine; premix of coconutalkyl sulfuric acid paste (containing propanediol, triethanolamine, coconutalkyl sulfuric acid, water and minors) and monoethanolamine-neutralized alkylbenzene sulfonic acid; premix of toluene sulfonate and water; citric acid; alkyl trimethylammonium chloride; premix of fatty acids; phosphonic acid; acetic acid; premix of dye, brightener, formate, ethanol and water; adjust pH to about 8.1 with monoethanolamine or water; protease enzyme; amylase enzyme; and perfume. The product obtained was a clear liquid. It exhibited better detergency performance than a similar product obtained by adding the fatty acids prior to adding the alkyltrimethylammonium chloride. The product also exhibited better detergency 14 performance, phase stability and a less objectionable base odor than a similar product obtained by adding the monoethanolamine after the premix of the coconutalkyl sulfuric acid paste and the neutralized alkylbenzene sulfonic acid.

Composition B was obtained by mixing the components.

Other compositions of the present invention are obtained when the alkyl trimethylammonium halides in the above compositions are replaced with coconutalkyl trimethylammonium chloride, decyi trimethylammonium methyisulfate, lauryl 10 difhydroxyethyl) methylammonium chloride, decyloxypropyl trimethylammonium chloride, lauryl pentamethylethylenediammonium chloride, lauryl diethanolamine cr coconutalkyl trimethylethylene diamine..

Other compositions herein are obtained when, in the above 15 compositions, the linear alkylbenzene sulfonic acid is replaced with coconutalkyl sulfuric acid or alkyl sulfuric acid, and when the coconutalkyl sulfuric acid is replaced with C14l5 alkyl ethoxy (1 avg.) sulfuric acid.

Compositions of the present invention are also obtained when 20 the lauric/myristic/oleic fatty acid mixture in the above compositions is replaced with coconut fatty acid or a 3:1 weight ratio mixture of lauric and myristic acid.

Granular detergents of the present invention can be obtained by spray-drying the above compositions and admixing heat-sensitive materials such as the enzymes.

Claims

1. 2. The composition of Claim 1 wherein the anionic surfactant comprises an alkyl sulfate of the formula ROiC^O^SOgM* wherein R is an alkyl chain having from 8 to 18 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, and x is from 0 to 4.

2. 3. The composition of Claim 2 wherein in the alkyl sulfate surfactant, R is an alkyl group containing from 12 to 15 carbon atoms, x is 0 and M is an alkali metal, ammonium or substituted ammonium cation.

3. 4. The composition of Claim 3 wherein the anionic surfactant additionally comprises a water-soluble salt of an alkylbenzene sulfonate, paraffin sulfonate, alkyl glyceryl ether sulfonate or an ester of an α-sulfonated fatty acid.

4. 5. The composition of Claim 3 wherein the anionic surfactant additionally comprises an alkali metal, ammonium or substituted ammonium salt of a linear alkylbenzene sulfonate containing from 11 to 13 carbon atoms in the alkyl chain. 17

5. 6. The composition of Claim 1 wherein the cosurfactant is selected from the chloride, bromide and methylsulfate g alkyl trimethylammonium salts, Cg_1g alkyl di(hydroxyethyl) methylamrnonium salts, ^8-16 alkyl 5 hydroxyethyldimethylammonium salts, and Cg_lg alkyloxypropyl trimethylammonium salts.

6. 7. The compositions of Claim 6 wherein the cosurfactant is decyl trimethylammonium methylsulfate, lauryl trimethylammonium chloride, myristyl trimethylammonium bromide and coconut alkyl 10 trimethylammonium chloride and methylsulfate.

7. 8. The compositions of Claim 1 wherein the fatty acid comprises a material containing from 10 to 14 carbon atoms, or mixtures thereof.

8. 9. The compositions of Claim 3 wherein the cosurfactant is 15 selected from the chloride, bromide and methylsulfate Cg_1g alkyl trimethylammonium salts, Cg_lg alkyl di( hydroxy ethyl) methylamrnonium salts, Cg _lg alkyl hydroxyethyldimethylammonium salts, and Cg_1g alkyloxypropyl trimethylammonium salts, and the fatty 20 acid comprises a material containing from 10 to 14 carbon atoms, or mixtures thereof.

9. 10. A liquid detergent composition according to Claim 9 comprising from 10% to 20% by weight of the anionic synthetic surfactant, from 1% to 4% by weight of the 25 cosurfactant, and from 10% to 20% by weight of the fatty acid.

10. 11. The composition of Claim 10 additionally comprising from 0.1 to 2% by weight of an enzyme suitable for use in detergent compositions selected from amylases, proteases, and mixtures thereof. 30 18

11. 12. The composition of Claim 11 additionally comprising from 3% to 10% by weight of citric acid.

12. 13. A method for laundering fabrics comprising contacting said fabrics with an aqueous solution having a pH of 6.0 to 8.5 at 20°C and containing at least 0.1% by weight of the composition of Claim 1. 14. a detergent composition according to Claim 1, substantially as hereinbefore described with particular reference to the accompanying Examples.

13. 15. A method according to Claim 13 for laundering fabrics, substantially as hereinbefore described with particular reference to Example I of the accompanying Examples. F.R. KELLY & CO., AGENTS FOR THE APPLICANTS.