DE3689385T2 - Stable liquid detergent. - Google Patents

Abstract

Heavy-duty liquid detergents containing an essential block polyester soil release agent; anionic surfactant; ethoxylated non-ionic surfactant; optional quaternary ammonium, amine, amide, or amine oxide surfactant; preferably fatty acid and/or poly-carboxylate builders; a neutralization system preferably comprising sodium, potassium and/or low levels of alkanolamines; and a solvent system comprising ethanol, polyol and/or water. The compositions are isotropic liquids providing a high level of detergency performance.

Description

Technical area

The present invention relates to liquid heavy-duty detergent compositions containing a soil release agent; anionic surfactant (preferably comprising a sulfonate surfactant and an alcohol ethoxylate sulfate surfactant); ethoxylated nonionic surfactant; an optional quaternary ammonium, amine, amide or amine oxide surfactant; preferably saturated fatty acid and polycarboxylate builders; a neutralizing system preferably comprising sodium, potassium and/or minor amounts of alkanolamines; and a solvent system preferably comprising ethanol, polyol and water. The compositions are isotropic liquids which provide a high level of detergent performance.

There is a significant need for liquid detergents capable of providing superior cleaning under a wide variety of laundry conditions. Such compositions generally require a number of ingredients which tend to separate into discrete phases. Isotropic liquid detergents are desirable for both performance consistency and aesthetic reasons. The compositions should remain isotropic during shipping and storage where temperatures of 55ºF (12.8ºC) or below are often encountered. They are also preferably formulated to present an isotropic phase after freezing and thawing prior to consumer use.

Liquid detergents desirably contain a soil release agent to enhance performance. However, soil release agents are difficult to incorporate into liquid detergents. There is therefore a continuing need for the development of an isotropic liquid detergent with a soil release agent capable of providing better cleaning, better bleach compatibility and better product stability.

State of the art

US 4,125,370 describes random ethylene terephthalate polyethylene oxide terephthalate polymers which are effective as soil removers.

European Patent Application 0 095 205, Wertz et al., published November 30, 1983, discloses detergent compositions containing anionic surfactants, quaternary ammonium, amine or amine oxide surfactants and fatty acids, formulated to maintain a pH close to neutrality during washing. The compositions are preferably liquid detergents which additionally comprise ethoxylated nonionic surfactants and polycarboxylate builders.

U.S. Patent No. 4,285,841, Barrat et al., issued August 25, 1981, describes liquid detergents comprising anionic surfactants, nonionic 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 about 7.0.

U.S. Patent No. 4,287,082, Tolfo et al., issued September 1, 1981, discloses liquid detergents containing saturated fatty acids, enzymes, enzyme-available calcium, and salts of short-chain carboxylic acids, preferably formates.

EP-A-185 427, Eugene P. Gosselink, published June 25, 1986, discloses liquid detergent compositions of the type claimed herein, which comprise block polyesters as soil release agents, which are in the same class as the present soil release agents.

Summary of the invention

The present invention relates to liquid heavy-duty detergent compositions comprising, by weight:

(a) 10% to 35% of an anionic surfactant on an acid base, preferably

(i) 5% to 15% of a sulfonate surfactant with a C₁₀-C₁₆ alkyl or alkenyl group; and

(ii) from 5% to 18%, on an acid basis, of an alcohol ethoxylate sulfate surfactant of the formula RO(C₂H₄O)mSO₃M, wherein R represents a C₁₀-C₁₆ alkyl or hydroxyalkyl group, m is from 0.5 to 4 and M is an compatible cation;

(b) from 0% to 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)nOH, wherein R¹ represents a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkylphenyl group, n averages from 3 to 9, and said nonionic surfactant has an HLB value of from 10 to 13;

(c) 0% to 15% of a co-surfactant selected from the group consisting of:

(i) quaternary ammonium surfactants of the formula:

[R²(OR³)y][R₄(OR³)y]₂R⁵N⁺X⁻

wherein R² represents an alkyl or alkylbenzyl group having 6 to 16 carbon atoms in the alkyl chain; each R³ is selected from the group consisting of -CH₂CH₂-, -CH₂CH(CH₃)-, -CH₂CH(CH₂OH)-, -CH₂CH₂CH₂-, and mixtures thereof; each R⁴ is selected from the group consisting of C₁-C₄ alkyl, C₁-C₄ hydroxyalkyl, benzyl, and is hydrogen when y is not 0; R⁵ has the same significance as R⁵ or represents an alkyl chain, wherein the total number of carbon atoms of R² plus R⁵ is from 8 to 16; each y averages from 0 to 10 and the sum of the y values is from 0 to 15; and X is any compatible anion;

ii) amine surfactants of the formula:

[R²(OR³)y][R⁴(OR³)y]R⁵N,

wherein R², R³, R⁴, R⁵ and y are as defined above;

iii) amine oxide surfactants of the formula:

[R²(OR³)y][R&sup4;(OR³)y]R&sup5;N → 0,

wherein R², R³, R⁴, R⁵ and y are as defined above; (iv) an amide surfactant of the formula:

wherein R⁶ represents an alkyl, hydroxyalkyl or alkenyl radical having 8 to 20 carbon atoms and R⁷ and R⁶ are each selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, and wherein said radicals additionally contain up to 5 ethylene oxide units and preferably at least one radical R⁷ and R⁶ contains a hydroxyl group; and

(v) mixtures thereof;

(d) 5% to 30% of detergent builder, preferably:

(i) 0% to 20% of a saturated C₁₀-C₁₄ fatty acid, wherein the weight ratio of C₁₀-C₁₂ fatty acid to C₁₄ fatty acid is at least 1; and

(ii) 3% to 20% on an acid basis of a water soluble polycarboxylate builder material;

(e) a neutralisation system, preferably:

(i) 0 to 0.05 moles per 100 g of the composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine and triethanolamine; and

(ii) potassium and sodium ions in a molar ratio of potassium to sodium of 0.1 to 1.3;

(f) a solvent system which does not consist exclusively of water, preferably:

(i) 2% to 10% ethanol;

(ii) 2% to 15% of a polyol having 2 to 6 carbon atoms and 2 to 6 hydroxy groups;

(iii) 25% to 40% water; and

(g) 0.25% to 4% of a soil release component which is a compound of the formula:

wherein each R¹ is 1,4-phenylene, R² is ethylene or preferably 1,2-propylene; each n is on average 10 to 50; each x is H and/or an alkyl group having 1 to 4 carbon atoms and/or an acyl group having 2 to 4 carbon atoms; wherein in less than 10 mole percent of said soil release compound u is greater than 5, in at least 20 mole percent of said soil release compound u is in the range of 3 to 5 and wherein the average value of u is from 3 to 5 .

Said compositions preferably comprise from 20% to 40% of (a), (b), (c) and (d); which components are selected to provide an isotropic liquid at 55°F (12.8°C) having an initial pH of from 7.5 to 9, preferably from 8.4 to 8.8, at a concentration of 19% by weight in water at 68°F (20°C).

Detailed description of the invention

The liquid detergents of the present invention include anionic surfactant, preferably a mixture of sulfonate and alcohol ethoxylate-sulfate anionic surfactants; ethoxylated nonionic surfactant; optional quaternary ammonium, amine, amide and/or amine oxide surfactants; builders, preferably saturated fatty acid and/or polycarboxylate builders; a neutralizing system, preferably comprising sodium, potassium and preferably small amounts of alkanolamines; and a solvent system, which system does not consist exclusively of water, which system preferably comprises ethanol, polyol and water.

The compositions of the invention are formulated to provide a high level of detergent performance under a large to ensure durability under a variety of laundry conditions. Preferred compositions of the invention are liquids that are isotropic at 50°F (10°C). They preferably also assume an isotropic form after freezing and thawing at 55°F (12.8°C), more preferably at 50°F (10°C).

The present compositions preferably comprise a neutralization system containing potassium and sodium ions in admixture. Complete neutralization by sodium contributes to crystallization of the polycarboxylate builder and little incorporation of the soil release polymer, whereas neutralization by potassium alone results in an unacceptably high gel point. The total amount of organic and inorganic bases should also be selected to achieve a sufficiently high product pH to reduce the amount of poorly soluble free fatty acid without being so high as to compromise stain removal, enzyme stability, soil release polymer stability and removal of greasy/oily soils, which are pH sensitive.

The compositions preferably also comprise a solvent system comprising water and a mixture of ethanol and polyol. Polyols such as propylene glycol are particularly effective in solubilizing the soil release polymer. Without the polyol, crystallization occurs and without ethanol, unacceptably high gel points tend to occur. The amount of ethanol and polyol must also be sufficient to prevent separation of the organic phase (i.e., to keep the free fatty acids and poorly soluble surfactants in solution), yet not so high that phase separation in the wash liquor and/or crystallization would occur by limiting the amount of water available.

The dirt-removing component

The dirt dissolving component has the general formula

wherein X is selected from the group consisting of H, alkyl groups having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms, or acyl groups having 2 to 4 carbon atoms, preferably alkyl groups, n is selected for water solubility and ranges from values averaging from 10 to 50, preferably 10 to 25. The selection of u is critical for formulating a liquid detergent having a relatively high ionic strength. There should be very little material, i.e. less than 10 mole percent, preferably less than 5 mole percent, more preferably less than 1 mole percent, where u is greater than 5. In addition, there should be at least 20 mole percent, preferably at least 40 mole percent of material where u ranges from 3 to 5. The average value for u is 3 to 5.

The R¹ residues are 1,4-phenylene residues.

Groups suitable for the R² groups include ethylene or 1,2-propylene and mixtures thereof. Although the inclusion of a larger percentage of ethylene groups tends to improve the soil-release activity of the compounds, the percentage included is limited by water solubility. Surprisingly, the inclusion of a larger percentage of 1,2-propylene groups tends to improve the water solubility of the compounds and consequently the ability to formulate isotropic aqueous detergent compositions without significantly affecting soil-release activity.

In this invention, the use of 1,2-propylene residues is extremely important for maximizing the incorporation of a significant percent of the soil release component in the liquid heavy-duty detergent compositions. Preferably, 75% to 100%, more preferably 90% to 100% of the R² residues are 1,2-propylene residues.

In general, soil release components which are soluble in cold ethanol (15°C) are also useful in compositions of the invention.

The value of n is on average at least 10, but there is a distribution of n values. The value of each n is usually from 10 to 50. Preferably the value of each n is on average in the range from 10 to 25.

A preferred method of preparing the soil release component comprises the step of extracting a polymer having a typical distribution, in which a substantial proportion comprises a material in which u is greater than 5, with substantially anhydrous ethanol at low temperatures, e.g. from 10°C to 15°C, preferably less than 13°C. The ethanol soluble fraction is substantially free of the longer polymers and is much more easily incorporated into isotropic heavy-duty detergent liquids, particularly those with higher builder levels. Although the polymers in which u is less than 3 have substantially no value in providing soil release effects, they can be more easily incorporated than those with higher u values.

A more preferred method for producing the soil release component is direct synthesis.

A more complete description of the soil release starting component and the processes for its preparation can be found in European Patent Application EP-A-185 427, filed on December 12, 1985 and published on June 26, 1986.

The anionic surfactant

The anionic surfactant herein may comprise any of the synthetic anionic surfactants conventionally used in heavy duty detergents, including alkylbenzene sulfonates, alkyl sulfates, alkyl polyethoxylate sulfates, olefin sulfonates, paraffin sulfonates, and the like. Mixtures may also be used. Suitable synthetic anionic surfactants are detailed in U.S. Patent No. 3,929,678, Laughlin et al., issued on December 30, 1975.

Preferred synthetic anionic surfactants include the sulfonates, the alkyl sulfates and alkyl polyethoxylate ether sulfates, which are discussed in more detail below.

Sulfonate surfactant

The detergent compositions of the present invention preferably contain from 5% to 15%, more preferably from 6% to 12% by weight (on an acid basis) of an anionic sulfonate surfactant containing a C10-C16 alkyl or alkenyl group. Anionic sulfonate surfactants useful herein are described in U.S. Patent No. 4,285,841, Barrat et al., issued August 25, 1981, and U.S. Patent No. 3,919,678, Laughlin et al., issued December 30, 1975.

Preferred sulfonate surfactants are the water-soluble salts, especially the alkali metal and alkanolammonium salts (e.g., monoethanolammonium salts or triethanolammonium salts) of alkylbenzenesulfonates wherein the alkyl group contains from 10 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. Particularly valuable are straight-chain alkylbenzenesulfonates wherein the average number of carbon atoms in the alkyl group is from 11 to 13.

Also useful here are the water-soluble salts of paraffin sulfonates, olefin sulfonates, alkyl glyceryl ether sulfonates, of esters of alpha-sulfonated fatty acids with 1 to 10 carbon atoms in the ester group, of 2-acyloxy-alkane-1-sulfonates with 2 to 9 carbon atoms in the acyl group and β-alkyloxyalkane sulfonates with 1 to 3 carbon atoms in the alkyl group.

Mixtures of the sulfonates described above, especially with the linear C₁₁₋₁₃ alkylbenzenesulfonates, can also be used.

Alcohol ethoxylate sulfate surfactant

The present compositions preferably contain an alcohol polyethoxylate ether sulfate surfactant of the formula RO(C₂H₄O)mSO₃M, wherein R is a C₁₀-C₁₆ alkyl group (preferred) or a hydroxyalkyl group, m is from 0.5 to 4 and M is an acceptable cation. This surfactant preferably represents from 5% to 18%, more preferably from 9% to 14% (on an acid basis) of the composition.

Preferred alcohol ethoxylate-sulfate surfactants of the above formula are those wherein the R substituent is a C12-15 alkyl group and m is from 1.5 to 3. Examples of such materials are C12-15 alkyl polyethoxylate (2,25) sulfate (C12-15E2,25S); C14-15E2,25S; C12-15E1,5S; C14-15E3S; and mixtures thereof. The sodium, potassium, monoethanolammonium and triethanolammonium salts of the above compounds are preferred.

Ethoxylated Nonionic Surfactant The compositions preferably also include from 2% to 15%, more preferably from 4% to 12%, by weight of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)nOH, wherein R¹ is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkylphenyl group, n is from 3 to 9, and which nonionic surfactant has an HLB (hydrophilic lipophilic balance) of from 10 to 13. These surfactants are more fully described in U.S. Patent Nos. 4,285,841, Barrat et al., issued August 25, 1981, and 4,284,532, Leikhim et al., issued August 18, 1981. Particularly preferred are condensation products of C12-C14 alcohols with from 3 to 8 moles of ethylene oxide per mole of alcohol, e.g., C12-C13 alcohol condensed with about 6.5 moles of ethylene oxide per mole of alcohol.

The ethoxylated nonionic surfactants used herein have an HLB (hydrophilic-lipophilic balance) value of 5 to 17, preferably 6 to 13. The HLB value is defined in detail in Nonionic Surfactants, M.J. Schick, Marcel Dekker, Inc., 1966, pages 607-613. Ethoxylated nonionic surfactants suitable herein are the following:

(1) The polyethylene oxide condensates of alkylphenols. These compounds include the condensation products of alkylphenols containing an alkyl group of 6 to 12 carbon atoms in either a straight chain or a branched chain configuration with ethylene oxide, which ethylene oxide is present in an amount of 3 to 25 moles of ethylene oxide per mole of alkylphenol.

Examples of compounds of this type include nonylphenol, which is condensed with about 9.5 moles of ethylene oxide per mole of nonylphenol; dodecylphenol, which is condensed with about 12 moles of ethylene oxide per mole of phenol; dinonylphenol, which is condensed with about 15 moles of ethylene oxide per mole of phenol; and diisooctylphenol, which is condensed with about 15 moles of ethylene oxide per mole of phenol. Commercially available nonionic surfactants of this type include Igepal® CO-630, which is sold by GAF Corporation, and Triton® X-45, X-114, X-100 and X-102, which are sold by Rohm & Haas Company.

(2) The condensation products of aliphatic alcohols with 1 to 25 moles of ethylene oxide. The alkyl chain of the primary or secondary aliphatic alcohol can be either straight or branched and generally contains 8 to 22 carbon atoms. Examples of such ethoxylated alcohols include the condensation product of myristyl alcohol condensed with about 10 moles of ethylene oxide per mole of alcohol; and the condensation product of about 9 moles of ethylene oxide and coconut alcohol (a mixture of fatty alcohols with alkyl chains varying in length from 10 to 14 carbon atoms). Examples of commercially available nonionic surfactants of this type include Tergitol® 15-S-9, which is sold by Union Carbide Corporation, Neodol® 45-9, Neodol® 23-6.5, Neodol® 45-7 and Neodol® 45-4, which are sold by Shell Chemical Company, and Kyro® EOB, which is sold by The Procter & Gamble Company.

(3) Mixtures of the above.

Preferred ethoxylated nonionic surfactants have the formula R¹(OC₂H₄)nOH, where R¹ is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkylphenyl group, n is from 3 to 9, and wherein said nonionic surfactant has an HLB (hydrophilic-lipophilic balance) value of from 9 to 13, preferably from 10 to 13.

Co-surfactant

The compositions of the invention may also contain from 0% to 15%, preferably from 0.5% to 3%, by weight of a co-surfactant selected from certain quaternary ammonium, amine, amide and/or amine oxide surfactants. The quaternary ammonium and amide surfactants are particularly preferred.

The quaternary ammonium surfactants useful herein have the formula:

[R²(OR³)y][R⁴(OR³)y]⁴R⁵N⁺X⁻,

wherein R² is an alkyl or alkylbenzyl group having 6 to 16 carbon atoms in the alkyl chain; each R³ is selected from the group consisting of -CH₂CH₂-, -CH₂CH(CH₃)-, -CH₂CH(CH₂OH)-, -CH₂CH₂CH₂- and mixtures thereof; each R⁴ is selected from the group consisting of C₁-C₄ alkyl, C₁-C₄ hydroxyalkyl, benzyl, and hydrogen when y is not 0; R⁵ has the same meaning as R⁵ or is an alkyl chain, the total number of carbon atoms of R² plus R⁵ being from 8 to 16; each y is from 0 to 10 and the sum of the y values is from 0 to 15; and X represents any compatible anion.

Preferred of the above are the alkyl quaternary ammonium surfactants, particularly the long chain monoalkyl surfactants described in the above formula when R5 is selected from the same groups as R4. The most preferred quaternary ammonium surfactants are the C8-16 alkyltrimethylammonium, C8-16 alkyldi(hydroxyethyl)methylammonium, C8-16 alkylhydroxyethyldimethylammonium, C8-16 alkyloxypropyltrimethylammonium and C8-16 alkyloxypropyldihydroxyethylmethylammonium salts. based on chloride, bromide and methyl sulfate. Of the above, the C₁₀-C₁₄ alkyltrimethylammonium salts are preferred, e.g., decyltrimethylammonium methylsulfate, lauryltrimethylammonium chloride, myristyltrimethylammonium bromide and coconut trimethylammonium chloride and methylsulfate.

Under cold water wash conditions, i.e., less than 65°F (18.3°C), the C8-10 alkyltrimethylammonium surfactants are particularly preferred because they have lower Krafft limits and crystallization temperatures than the longer chain quaternary ammonium surfactants.

Amine surfactants useful here have the formula:

[R²(OR³)y][R⁴(OR³)y]R⁵N,

wherein the R², R³, R⁴, R⁵ substituents and y are as defined above for the quaternary ammonium surfactants. Particularly preferred are the C₁₂₋₁₆ alkyldimethylamines.

Amine oxide surfactants useful herein have the formula:

[R²(OR³)y][R&sup4;(OR³)y]R&sup5;N → 0,

wherein the R2, R3, R4, R5 substituents and y are as defined above for the quaternary ammonium surfactants. Particularly preferred are the C12-16 alkyldimethylamine oxides.

Amine and amine oxide surfactants are preferably used in higher amounts than the quaternary ammonium surfactants since they are only partially protonated in the present systems. For example, preferred compositions of the invention may contain 0.5% to 1.5% of the quaternary ammonium surfactant or 1% to 3% of the amine or amine oxide surfactant.

Amide surfactants herein have the formula

wherein R6 represents an alkyl, hydroxyalkyl or alkenyl radical having 8 to 20 carbon atoms and R7 and R8 are selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, and which radicals additionally contain up to 5 ethylene oxide units, with the proviso that at least one of R7 and R8 has a hydroxyl group.

Preferred amides are the C8-C20 fatty acid alkylolamides, wherein each alkylol group contains 1 to 3 carbon atoms, and can additionally have up to 2 ethylene oxide units. The C12-C14 fatty acid monoethanol and diethanolamides are particularly preferred.

fatty acid

The compositions of the present invention preferably include from 0% to 20%, more preferably from 8% to 18%, most preferably from 10% to 16%, by weight of a saturated fatty acid containing from 10 to 14 carbon atoms. In addition, the weight ratio of C₁₀-C₁₂ fatty acid to C₁₄ fatty acid is preferably at least 1, more preferably at least 1.5.

Suitable saturated fatty acids can be obtained from natural sources such as plant or animal esters (e.g. palm kernel oil, palm oil and coconut oil) or they can be produced synthetically (e.g. by oxidation of petroleum or by hydrogenation of carbon monoxide using the Fischer-Tropsch process). Examples of suitable saturated fatty acids for use in the compositions of this invention include capric acid, lauric acid, myristic acid, coconut and palm kernel fatty acids. Preferred are saturated coconut fatty acids, mixtures of lauric and myristic acids in a weight ratio of 5:1 to 1:1 (preferably about 3:1), mixtures of the foregoing with minor amounts (e.g. 10%-50% of the total fatty acid) of oleic acid; and palm kernel fatty acid.

Polycarboxylate builder

The compositions according to the invention preferably also contain 3 wt.% to 20 wt.%, more preferably 3 wt.% to 6%, more preferably 3.5% to 5% by weight on an acid basis, of a water-soluble polycarboxylate detergent builder material. Polycarboxylate builders are described in U.S. Patent No. 4,284,532, Leikhim et al., issued August 18, 1981.

The various aminopolycarboxylates, cycloalkanepolycarboxylates, etherpolycarboxylates, alkylpolycarboxylates, epoxypolycarboxylates, tetrahydrofuranpolycarboxylates, benzenepolycarboxylates and polyacetalpolycarboxylates are suitable for use according to the invention.

Examples of such polycarboxylate builders are sodium and potassium ethylenediaminetetraacetate; sodium and potassium nitrilotriacetate; the water-soluble salts of phytic acid, e.g., sodium and potassium phytates, described in U.S. Patent 1,739,942, Eckey, issued March 27, 1956; the polycarboxylate materials described in U.S. Patent 3,364,103, and the water-soluble salts of polycarboxylate polymers and copolymers described in U.S. Patent 3,308,067, Diehl, issued March 7, 1967.

Useful detergent builders also include the water-soluble salts of polymeric aliphatic polycarboxylic acids having the following structural and physical properties: (a) a minimum molecular weight of 350, calculated for the acid form; (b) an equivalent weight of from 50 to 80, calculated for the acid form; (c) at least 45 mole percent of the monomeric species have at least two carboxyl residues separated from each other by not more than two carbon atoms; (d) the bonding site between the polymeric chain and any carboxyl-containing residue is separated by not more than three carbon atoms along the polymer chain from the bonding site of the next carboxyl-containing residue. Specific examples of such builders are the polymers and copolymers of itaconic acid, aconitic acid, maleic acid, mesaconic acid, fumaric acid, methylenemalonic acid and citraconic acid.

Other suitable polycarboxylate builders include the water-soluble salts, in particular the sodium and potassium salts of mellitic acid, citric acid, pyromellitic acid, benzene pentacarboxylic acid, oxydiacetic acid, carboxymethyloxysuccinic acid, Carboxymethyloxymalonic acid, cis-cyclohexanehexacarboxylic acid, cis-cyclopentanetetracarboxylic acid and oxydisuccinic acid.

Other polycarboxylates for use herein are the polyacetal carboxylates described in U.S. Patent No. 4,144,226, issued March 13, 1979, Crutchfield et al., and U.S. Patent No. 4,146,495, issued March 27, 1979, Crutchfield et al.

Citric acid is a highly preferred polycarboxylate builder.

Neutralization system

The present compositions may contain from 0 to 0.04 moles, preferably from 0.01 to 0.035 moles, more preferably from 0.015 to 0.03 moles, per 100 grams of composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, and mixtures thereof. Small amounts of alkanolamines or none, particularly monoethanolamine, are preferred to improve product stability, detergent performance, and odor. The amount of alkanolamine should be minimized to achieve the best chlorine bleach compatibility and stability of the soil release component. Although the present compositions may contain mixtures of the alkanolamines, the best color fastness is achieved using individual alkanolamines.

Solvent system

The solvent system for the compositions preferably consists of ethanol, a polyol, e.g. propanediol, and water. Ethanol is preferably present in an amount of from 2% to 10%, more preferably from 5% to 9%, by weight of the composition.

Any polyol containing 2 to 6 carbon atoms and 2 to 6 hydroxy groups can be used in the present compositions. Examples of such polyols are ethylene glycol, propanediol, propylene glycol and glycerin. Propylene glycol is particularly preferred. The polyol preferably represents 2 wt.% to 15 wt.%, more preferably 3 wt.% to 10 % by weight of the composition.

The compositions preferably contain 25% to 40% by weight, more preferably 28% to 37% by weight of water.

In addition to the above, the ethanol and polyol together preferably constitute from 8% to 20%, more preferably from 11% to 16%, of the composition. The total ethanol, polyol and water preferably constitute from 35% to 55%, more preferably from 40% to 50%, of the composition.

The compositions of the present invention preferably have the following limits, with all percentages and ratios calculated on an acid basis when anionic materials are involved. The sulfonate, alcohol ethoxylate, sulfate, ethoxylated nonionic and quaternary ammonium, amine, amide and/or amine oxide surfactants in total preferably constitute from 20% to 40%, more preferably from 23% to 30% by weight of the composition.

The fatty acid and the polycarboxylate builder together preferably constitute from 5% to 30%, more preferably from 10% to 25%, by weight of the composition. In addition, the fatty acid, the polycarboxylate builder and the above surfactants preferably constitute a total of from 33% to 50%, more preferably from 36% to 48%, by weight of the composition.

Finally, all of the above components are selected to provide a liquid detergent that is isotropic at 55°F (12.8°C), preferably at 50°F (10°C). The components are also selected to provide an initial pH of 7.5 to 9.0, preferably 7.8 to 8.8, at a concentration of 10% by weight in water at 68°F (20°C).

Optional components

Optional components for use in the liquid detergents of the invention include enzymes, enzyme stabilizing agents, polyacids, soil removing agents, antiredeposition agents, foam regulators, hydrotropes, opacifiers, antioxidants, bactericides, dyes, perfumes and brighteners described in U.S. Patent No. 4,285,841, Barrat et al., issued August 25, 1981. Such optional components generally constitute less than 15%, preferably 2% to 10%, by weight of the composition.

Enzymes are highly preferred optional ingredients and are incorporated in an amount of from 0.025% to 2%, preferably from 0.05% to 1.5%. Preferred proteolytic enzymes should provide a proteolytic activity of at least 5 Anson units (about 1,000,000 Delft units) per liter, preferably from 15 to 70 Anson units per liter, most preferably from 20 to 40 Anson units per liter. A proteolytic activity of from 0.01 to 0.05 Anson units per gram of product is desirable. Other enzymes, including amylolytic enzymes, are also desirably included in the present compositions.

Suitable proteolytic enzymes include the many species known to be suitable for use in detergent compositions. Commercial enzyme preparations such as "Alcalase"®, sold by Novo Industries, and "Maxatase"®, sold by Gist-Brocades, Delft, The Netherlands, are suitable. Other preferred enzyme compositions include those commercially available under the trade names SP-72 ("Esperase"®), manufactured and sold by Novo Industries, A/5, Copenhagen, Denmark, and "AZ-Protease"®, manufactured and sold by Gist-Brocades, Delft, The Netherlands.

Suitable amylases include "Rapidase"®, sold by Gist-Brocades, and "Termamyl"®, sold by Novo Industries.

A more complete list of suitable enzymes can be found in U.S. Patent No. 4,101,457, Place et al., issued July 18, 1978.

When enzymes are incorporated in the detergent compositions of this invention, they are preferably stabilized using a mixture of a salt of a short chain carboxylic acid and calcium ions as described in U.S. Patent No. 4,318,818, Letton et al., issued March 9, 1982.

The short chain carboxylic acid salt is preferably water soluble and most preferably is a formate, e.g. sodium formate. The short chain carboxylic acid salt is used in an amount of from about 0.25% to about 10%, preferably from 0.3% to 3%, more preferably from 0.5% to 1.5%. Any water soluble calcium salt can be used as the source of calcium ions, including calcium acetate, calcium formate and calcium propionate. The composition should contain from 0.1 to 30 millimoles of calcium ions per liter, preferably from 0.5 to 15 millimoles of calcium ions per liter. If materials are present which complex calcium ions, it is necessary to use higher amounts of calcium ions so that there is always some minimum amount available to the enzyme.

Enzymes are stabilized in the present compositions by the addition of from 0.25% to 10%, preferably from 0.5% to 5%, more preferably from 0.75% to 3% by weight of boric acid or a compound capable of forming boric acid in the composition (calculated on the basis of boric acid). Boric acid is preferred, although other compounds such as boron trioxide, borax and other alkali metal borates (e.g., sodium ortho-, meta- and pyroborate and sodium pentaborate) are suitable. Substituted boric acids (e.g., phenylboronic acid, butaneboronic acid and p-bromophenylboronic acid) may also be used in place of boric acid.

The combination of boric acid and formate provides improved protease stability, although amylase stability appears to be slightly lower than that achieved by using boric acid alone.

Preferred compositions also include 0.01% to 1% of a polyacid or salt thereof to enhance pretreatment performance. Preferred polyacids for use in the present invention are ethylenediaminetetramethylenephosphonic acid, diethylenetriaminepentamethylenephosphonic acid and diethylenetriaminepentaacetic acid or the salts thereof. These polyacids/salts are preferably used in an amount of 0.1% to 0.8%.

Preferred compositions of the invention further include from 0.5% to 3%, preferably from 1% to 2%, by weight of a highly ethoxylated polyethyleneamine or polyethyleneimine soil removal and antiredeposition agent. A particularly preferred species of such soil removal and antiredeposition agent is tetraethylenepentamine ethoxylated with about 15-18 moles of ethylene oxide at each hydrogen site.

The following examples illustrate the compositions of the present invention.

All parts, percentages and ratios used herein are by weight unless otherwise specified.

EXAMPLE I

A liquid detergent composition of the present invention is as follows:

A compound which comprises a number of copolymers of the formula:

wherein about 20% by weight of the material has a value of u greater than 5, is dissolved in an amount of about 15% in anhydrous ethanol; it is cooled to about 10°C; the insoluble portion (about 20%) is filtered off; sufficient ethanol is distilled off to reduce the amount of ethanol to the amount in the following formulation, and the compound is added to the formulation.

Components % C₁₄₋₁₅-alkyl polyethoxylate (2,25)- sulfuric acid half ester 12.0

C₁₃-Alkylbenzenesulfonic acid 8.0

C₁₂₋₁₃-alkyl polyethoxylate (6.5) 5.0

C₁₂-alkyltrimethylammonium chloride 0.6

Medium cut coconut fatty acid 7.7

Palm kernel oil fatty acids 3.3

Diethylenetriaminepentaacetic acid 0.3

Citric acid 4.0

ethanol 6.0

1,2-Propanediol 8.0

Monoethanolamine 1.0

Sodium hydroxide 2.5

Potassium hydroxide 4.7

Tetraethylenepentamine, ethoxylated with approximately 16 moles of ethylene oxide on each hydrogen atom 2.0

the above mentioned dirt dissolving component 2.5

Water, enzymes, brighteners, etc.

Product pH approximately 8.3

EXAMPLE II

A liquid detergent composition of the present invention is as follows:

A compound which comprises a number of copolymers of the formula:

wherein about 20% by weight of the material has a value of u which is greater than 5, is dissolved in an amount of about 15% in anhydrous ethanol; it is heated to about 10ºC cooled; the insoluble portion (approximately 20%) is filtered off; sufficient ethanol is distilled off to reduce the amount of ethanol to the amount in the following formulation and the compound is added to the formulation. Components % C₁₁₋₁₈ alkylbenzenesulfonic acid 10.3

C₁₂₋₁₄-alkyl sulfate (acid) 2.6

Triethanolamine 6.5

Sodium hydroxide 3.4

C₁₃₋₁₅-alkyl polyethoxylate (7.0) 11.6

Ethanol 5.7

1,2-Propanediol 1,6

Sodium formate (40% solution) 1.0

Calcium chloride 0.02

Diethylenetriaminepenta(methylenephosphonic acid) 0.9

Citric acid monohydrate 0.9

topped full-cut fatty acid 10.7

Oleic acid 3.9

the above mentioned dirt release compound 0.5

Water, enzymes, brighteners and other residue

Claims (18)

1. A liquid heavy-duty detergent composition comprising, by weight: (a) 10% to 35% of an anionic surfactant on an acid base; (b) from 0% to 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)nOH, wherein R¹ represents a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkylphenyl group, n averages from 3 to 9, and said nonionic surfactant has an HLB value of from 10 to 13; (c) 0% to 15% of a co-surfactant selected from the group consisting of: (i) quaternary ammonium surfactants of the formula: [R²(OR³)y][R⁴(OR³)y]₂R⁵N⁺X⁻; wherein R² represents an alkyl or alkylbenzyl group having 6 to 16 carbon atoms in the alkyl chain; each R³ is selected from the group consisting of -CH₂CH₂-, -CH₂CH(CH₃)-, -CH₂CH(CH₂OH)-, -CH₂CH₂CH₂- and mixtures thereof; each R is selected from the group consisting of C₁-C₄alkyl, C₁-C₄hydroxyalkyl, benzyl and is hydrogen when y is not 0; R⁵ has the same significance as R⁵ or represents an alkyl chain, the total number of carbon atoms of R² plus R⁵ being from 8 to 16; each y is on average from 0 to 10 and the sum of the y values is from 0 to 15; and X is any compatible anion; ii) amine surfactants of the formula: [R²(OR³)y][R⁴(OR³)y]R⁵N, wherein R², R³, R⁴, R⁵ and y are as defined above; iii) amine oxide surfactants of the formula: [R²(OR³)y][R&sup4;(OR³)y]R&sup5;N → 0, wherein R², R³, R⁴, R⁵ and y are as defined above; (iv) an amide surfactant of the formula: wherein R⁶ represents an alkyl, hydroxyalkyl or alkenyl radical having 8 to 20 carbon atoms and R⁷ and R⁶ are each selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl and wherein said radicals additionally contain up to 5 ethylene oxide units; and (v) mixtures thereof; (d) 5% to 30% detergent builder; (e) a neutralisation system; (f) an aqueous solvent system, said system not consisting exclusively of water; (g) 0.25% to 4% of a soil release component which is a compound of the formula: wherein each R¹ is 1,4-phenylene, each R² is ethylene or 1,2-propylene; each n is on average 10 to 50; each X is H, an alkyl radical having 1 to 4 carbon atoms or an acyl radical having 2 to 4 carbon atoms; wherein in less than 10 mol% of said soil release compound u is more than 5, in at least 20 mol% of said soil release compound u is in the range of 3 to 5 and wherein the average value of u is from 3 to 5. 2. Composition according to claim 1, wherein in component (g) n is from 10 to 25 and 90% to 100% of the radicals R² are 1,2-propylene radicals. 3. Composition according to claim 2, wherein X represents an alkyl radical having 1 to 2 carbon atoms. 4. Composition according to claim 2, wherein component (g) is a polymer fraction soluble in absolute ethanol at a temperature of 10°C to 15°C. 5. A composition according to claim 1, wherein component (g) is a polymer fraction soluble in absolute ethanol at a temperature of 10°C to 15°C. 6. A composition according to claim 5, wherein the detergent composition comprises, by weight: (a) from 5% to 15%, on an acid basis, of a sulfonate surfactant having a C₁₀-C₁₆ alkyl or alkenyl group; (b) from 8% to 18%, on an acid basis, of an alcohol ethoxylate-sulfate surfactant of the formula RO(C₂H₄O)mSO₃M, wherein R is a C₁₀-C₁₆ alkyl or hydroxyalkyl group, m is from 0.5 to 4 and M is an acceptable cation; and (c) from 2% to 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)nOH, wherein R¹ is a C₁₀-C₁₆ alkyl group or a C₈-C¹² alkylphenyl group, n is from 3 to 9 and said nonionic surfactant has an HLB value of from 10 to 13. 7. A composition according to claim 5, wherein the detergent composition, by weight, (a) from 5% to 15%, on an acid basis, of a sulfonate surfactant having a C₁₀-C₁₆ alkyl or alkenyl group; (b) 1% to 4%, on an acid basis, of a C₁₀-C₁₆ alkyl sulfate; and (c) from 2% to 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)nOH, wherein R¹ represents a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkylphenyl group, n is from 3 to 9 and said nonionic surfactant has an HLB value of from 10 to 13. 8. The composition of claim 6 wherein the sulfonate surfactant is a C11-C13 linear alkylbenzenesulfonate; wherein in the alcohol ethoxylate sulfate surfactant, R is a C12-C15 alkyl group and m is from 1.5 to 3, and wherein in the ethoxylated nonionic surfactant, R is a C12-C14 alkyl group and n is from 3 to 7. 9. A composition according to claim 8 comprising 0.5% to 3% by weight of the co-surfactant which is a C₁₀-C₁₄ alkyl trimethyl ammonium chloride, bromide or methyl sulfate. 10. A composition according to claim 8, wherein the builder comprises a polycarboxylate builder. 11. The composition of claim 8 comprising, by weight, 6% to 10% of the sulfonate surfactant, 9% to 14% of the alcohol ethoxylate sulfate surfactant, 4% to 10% of the ethoxylated nonionic surfactant, and 0.5% to 1.5% of the co-surfactant which is a C10-C14 alkyl trimethyl ammonium chloride, bromide or methyl sulfate. 12. A composition according to claim 11, wherein the builder comprises, based on the weight of the composition, 10% to 16% of saturated fatty acid and 3% to 6% citric acid. 13. A composition according to claim 12 comprising 0 to 0.035 moles per 100 g of composition of an alkanolamine which is monoethanolamine. 14. The composition of claim 13 comprising, by weight, 5% to 9% ethanol, 3% to 10% of a polyol which is propylene glycol, and 28% to 37% water. 15. The composition of claim 14 having an initial pH of 7.8 to 9.0 at a concentration of 10% by weight in water at 68°F (20°C). 16. Process for preparing a soil release component of the formula: wherein each R¹ represents a 1,4-phenylene radical, each R² represents an ethylene or a 1,2-propylene radical; each X is selected from the group consisting of hydrogen, alkyl groups having 1 to 4 carbon atoms, and acyl groups having 2 to 4 carbon atoms; n is on average from 10 to 50; wherein in less than 10 mole percent of said soil release component u is more than 5, in at least 20 mole percent of said soil release component u is in the range of 3 to 5, and wherein the average value of u is from 3 to 5; comprising the step of dissolving a soil release component comprising the desired material and a substantial amount of material wherein u is greater than 5 in absolute alcohol at a temperature of 10ºC to 15ºC and separating the precipitated material. 17. Ethanol-soluble dirt-removing component of the formula wherein each R¹ is 1,4-phenylene, each R² is ethylene or 1,2-propylene; each n is from 10 to 50 on average; each X is H, an alkyl group having 1 to 4 carbon atoms or an acyl group having 2 to 4 carbon atoms, wherein 90% to 100% of the R² groups are 1,2-propylene, and wherein in less than 10 mol% of said soil release compound u is greater than 5, in at least 20 mol% of said soil release compound u is in the range of 3 to 5, and wherein the average value of u is from 3 to 5; obtainable by the process of claim 16. 18. The component of claim 17, wherein each X is an alkyl group having 1 to 2 carbon atoms.