EP0199403A2

EP0199403A2 - Stable liquid detergent compositions

Info

Publication number: EP0199403A2
Application number: EP86200584A
Authority: EP
Inventors: Eugene Paul Gosselink; Larry James Hughes; Antoinette Louise Larrabee; Robert Mermelstein; Nodie Monroe Washington
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1985-04-15
Filing date: 1986-04-07
Publication date: 1986-10-29
Anticipated expiration: 2006-04-07
Also published as: AU5612086A; EP0199403A3; DE3689385T2; ATE98674T1; EP0199403B1; AU601679B2; DE3689385D1

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 Field

The present invention relates to heavy-duty liquid detergent compositions containing a soil release agent; anionic surfactant (preferably comprising a sulfonate surfactant and 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 neutralization system preferably comprising sodium, potassium and/or low levels of alkanolamines; and a solvent system preferably comprising ethanol, polyol and water. The compositions are isotropic liquids which provide a high level of detergency performance.
There has been considerable demand for liquid detergents capable of providing superior cleaning under a wide variety of laundering conditions. Such compositions generally require a number of ingredients which tend to separate into discrete phases. Isotropic liquid detergents are desired for both consistency of performance and aesthetic reasons. The compositions should remain isotropic during shipping and storage, where temperatures of 55°F (12.8°C) or lower are often encountered. They preferably are also formulated to recover, after freezing and thawing, to an isotropic phase prior to consumer use.
Liquid detergents desirably contain a soil release agent to enhance performance. However, soil release agents are difficult to incorporate in liquid detergents. Thus, there is a continuing need for the development of an isotropic liquid detergent with a soil release agent capable of providing superior cleaning, bleach compatibility and product stability.

Background Art

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, and formulated to provide a near-neutral wash pH. The compositions are preferably liquid detergents which additionally contain ethoxylated nonionic surfactants and polycarboxylate builders.
U.S. Patent 4,285,841, Barrat et al, issued August 25, 1981, discloses liquid detergents containing 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 7.5.
U.S. Patent 4.287,082, Tolfo et al, issued September 1, 1981, discloses liquid detergents containing saturated fatty acids, enzymes. enzyme- accessible calcium and short-chain carboxylic acid salts, preferably formates.
European Patent Application 85202053.6. Eugene P. Gosselink, filed December 12. 1985 discloses block polyester soil release agents. All of the above patents and applications are incorporated herein by reference.

Summary of the Invention

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

(a) from about 10% to about 35%, of an anionic surfactant on an acid basis, preferably:
- (i) from about 5% to about 15% of a sulfonate surfactant containing a C₁₀-C₁₆ alkyl or alkenyl group: and
- (ii) from about 5% to about 18%. on an acid basis, of an alcohol ethoxylate sulfate surfactant of the formula RO(C₂H₄O)-_mS03M, wherein R is a C₁₀-C₁₆ alkyl or hydroxyalkyl group, m is from about 0.5 to about 4, and M is a compatible cation;
(b) from 0% to about 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)_nOH, wherein R' is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkyl phenyl group, n averages from about 3 to about 9, and said nonionic surfactant has an HLB of from about 10 to about 13;
(c) from about 0% to about 15% of a cosurfactant selected from the group consisting of:
- (i) quaternary ammonium surfactants having the formula:
  wherein R² is an alkyl or alkyl benzyl group having from about 6 to about 16 carbon atoms in the alkyl chain; each R' 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-C₄ alkyl, C₁-C₄ hydroxyalkyl, benzyl, and hydrogen when y is not 0; R⁵ is the same as R' or is an alkyl chain wherein the total number of carbon atoms of R² plus R⁵ is from about 8 to about 16; each y averages from 0 to about 10 and the sum of the y values is from 0 to about 15; and X is any compatible anion;
- (ii) amine surfactants having the formula:
wherein R', R', R⁴, R⁵ and y are as defined above;
- (iii) amine oxide surfactants having the formula:
wherein R², R³, R⁴, R⁵ and y are as defined above; (iv) an amide surfactant of the formula
wherein R⁶ is an alkyl, hydroxyalkyl or alkenyl radical containing from about 8 to about 20 carbon atoms, and R and R⁸ 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 about 5 ethylene oxide units, and, preferably, at least one of R⁷ and R⁸ contains a hydroxyl group; and
- (v) mixtures thereof;
(d) from about 5% to about 30% of builder, preferably:
- (i) from 0% to about 20% of a C,o-C,₄ saturated fatty acid, the weight ratio of C₁₀-C,2 fatty acid to C,₄ fatty acid being at least 1; and
- (ii) from about 3% to about 20%, on an acid basis, of a water-soluble polycarboxylate builder material;
(e) a neutralization system, preferably:
- (i) from 0 to about 0.05 moles per 100 grams of composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine and triethanolamine; and
- (ii) potassium and sodium ions in a potassium to sodium molar ratio of from about 0.1 to about 1.3;
(f) a solvent system, preferably:
- (i) from about 2% to about 10% ethanol;
- (ii) from about 2% to about 15% of a polyol containing from 2 to 6 carbon atoms and from 2 to 6 hydroxy groups;
- (iii) from about 25% to about 40% water; and
(g) from about 0.25% to about 4% of a soil release component which comprises an effective amount of a soil release compound having the formula:

wherein each R' moiety is a phenylene moiety, preferably 1,4-phenylene; R² is an ethylene or, preferably, a 1,2-propylene moiety; each n averages about 10 to about 50; each X is H, and/or an alkyl and/or acyl radical containing from 1 to about 4 carbon atoms; and u is a range of values from about 3 to about 5; there being present only minimal amounts of similar compounds in which u is 6 or more and, preferably, there is a substantial amount of similar material present with u being 2 or less.

Said compositions preferably contain from about 20% to about 40% of (a), (b), (c) and (d); said components being selected to provide an isotropic liquid at 55°F (12.8°C) having an initial pH of from about 7.5 to about 9, preferably from about 8.4 to about 8.8, at a concentration of about 10% by weight in water at 68°F (20°C).

Detailed Description of the Invention

The liquid detergents of the present invention contain 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 neutralization system, preferably comprising sodium, potassium and preferably low levels of aI- kanolamines; and a solvent system, preferably comprising ethanol, polyol and/or water.
The compositions herein are formulated to provide a high level of detergency performance under a wide variety of laundering conditions. Preferred compositions herein are isotropic liquids at 50°F - (10°C). They preferably also recover, after freezing and thawing, to an isotropic form by 55°F (12.8°C), more preferably by 50°F (10°C).
The present compositions preferably comprise a neutralization system comprising mixed potassium and sodium ions. Complete sodium neutralization tends to cause crystallization of the polycarboxylate builder and poor incorporation of the soil release polymer, whereas all potassium neutralization results in an unacceptably high gel point. The total level of organic and inorganic bases should also be selected to provide a sufficiently high product pH to minimize the level of poorly-soluble free fatty acids, without being so high that pH sensitive stain removal, enzyme stability, soil release polymer stability, and greasyioily soil removal are compromised.
The compositions also preferably have a solvent system comprising water and a mixture of ethanol and polyol. Polyols such as propylene glycol are especially good at solubilizing the soil release polymer. Crystallization occurs without the polyol and unacceptably high gel points tend to occur without the ethanol. The amount of ethanol and polyol must also be sufficient to prevent organic phase separation (i.e., keep free fatty acids and poorly soluble surfactants in solution), and yet not be so high as to cause lye phase separation and/or crystallization by limiting the amount of water available.

The Soil Release Component

The soil release component has the generic formula

in which X can be any suitable capping group, with each X being selected from the group consisting of H, and alkyl or acyl groups containing from 1 to about 4 carbon atoms, preferably 1 to 2 carbon atoms, most preferably alkyl. n is selected for water solubility and is a range of values which generally averages from about 10 to about 50, preferably from about 10 to about 25. The selection of u is critical to formulation in a liquid detergent having a relatively high ionic strength. There should be very little material, preferably less than about 10 mol %, more preferably less than 5 mol %, most preferably less than 1 mol %, in which u is greater than 5. Furthermore there should be at least 20 mol %, preferably at least 40 mol %, of material in which u ranges from 3 to 5.
The R' moieties are essentially 1,4-phenylene moieties. As used herein, the term "the R' moieties are essentially 1,4-phenylene moieties" refers to compounds where the R' moieties consist entirely of 1,4-phenylene moieties, or are partially substituted with other arylene or alkarylene moieties, alkylene moieties, alkenylene moieties, or mixtures thereof. Arylene and alkarylene moieties which can be partially substituted for 1,4-phenylene include 1,3-phenylene, 1,2-phenylene, 1,8-naphthylene, 1,4-naphthylene, 2,2-biphenylene, 4,4'-biphenylene and mixtures thereof. Alkylene and alkenylene moieties which can be partially substituted include ethylene, 1,2-propylene, 1,4-butylene, 1,5-pentylene, 1,6-hexamethylene, 1,7-heptamethylene, 1,8-octamethylene, 1,4-cyclohexylene, and mixtures thereof.
For the R' moieties, the degree of partial substitution with moieties other than 1,4-phenylene should be such that the soil release properties of the compound are not adversely affected to any great extent. Generally, the degree of partial substitution which can be tolerated will depend upon the backbone length of the compound, i.e., longer backbones can have greater partial substitution for 1,4-phenylene moieties. Usually, compounds where the R' comprise from about 50% to 100% 1,4-phenylene moieties (from 0 to about 50% moieties other than 1,4-phenylene) have adequate soil release activity. For example, polyesters made according to the present invention with a 40:60 mole ratio of isophthalic (1,3-phenylene) to terephthalic - (1,4-phenylene) acid have adequate soil release activity. However, because most polyesters used in fiber making comprise ethylene terephthalate units, it is usually desirable to minimize the degree of partial substitution with moieties other than 1,4-phenylene for best soil release activity. Preferably, the R' moieties consist entirely of (i.e., comprise 100%) 1,4-phenylene moieties, i.e. each R' moiety is 1,4-phenylene.
For the R² moieties, suitable ethylene or substituted ethylene moieties include ethylene, 1,2-propylene, 1,2-butylene, 1,2-hexylene, 3-methoxy-1,2-propylene and mixtures thereof. Preferably, the R² moieties are essentially ethylene moieties, or, preferably, 1,2-propylene moieties or mixtures thereof. Although inclusion of a greater percentage of ethylene moieties tends to improve the soil release activity of the compounds, the percentage included is limited by water solubility. Surprisingly, inclusion of a greater percentage of 1,2-propylene moieties tends to improve the water solubility of the compounds and consequently the ability to formulate isotropic aqueous detergent compositions without significantly harming soil release activity.
For this invention, the use of 1,2-propylene moieties or a similar branched equivalent is extremely important for maximizing incorporation of a substantial percentage of the soil release component in the heavy duty liquid detergent compositions. Preferably, from about 75% to about 100%, more preferably from about 90% to about 100% of the R² moieties are 1,2-propylene moieties.
In general, soil release components which are soluble in cool (15°C) ethanol are also useful in compositions of the invention.
The value for n averages at least about 10, but a distribution of n values is present. The value for each n usually ranges from about 10 to about 50. Preferably, the value for each n averages in the range of from about 10 to about 25.
A preferred process for making the soil release component comprises the step of extracting a polymer having a typical distribution in which a substantial portion comprises a material in which u is equal to or greater than 6 with essentially anhydrous ethanol at low temperatures, e.g. from about 10°C to about 15°C, preferably less than about 13°C. The ethanol soluble fraction is substantially free of the longer polymers and is much easier to incorporate into isotropic heavy duty liquids. especially those with higher builder levels. Although the polymers wherein u is less than about 3 are essentially of no value in providing soil release effects, they can be more easily incorporated than higher u values.
A more preferred process for making the soil release component is by direct synthesis.
A more comprehensive disclosure of the soil release component and methods for making it can be found in European Patent Application 85202053.6, filed December 12, 1985, by Eugene P. Gosselink, incorporated herein by reference.

The Anionic Surfactant

The anionic surfactant herein can comprise any of the synthetic anionic surfactants conventionally used in heavy duty laundry detergents including alkyl benzene sulfonates, alkyl sulfates, alkyl polyethoxylate sulfates, olefin sulfonates, paraffin sulfonates, etc. Mixtures can also be used. Suitable synthetic anionic surfactants are disclosed in detail in U.S. Patent 3,929,678, Laughlin et al, issued December 30, 1975 and incorporated herein by reference.
Preferred synthetic anionic surfactants include .the sulfonates, the alkyl sulfates, and alkyl- polyethoxylate ether sulfates discussed more specifically below.

Sulfonate Surfactant

The detergent compositions herein preferably contain from about 5% to about 15%, more preferably from about 6% to about 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 disclosed in U.S. Patent 4,285,841, Barrat et al, issued August 25, 1981, and in U.S. Patent 3,919,678, Laughlin et al, issued December 30, 1975, both incorporated herein by reference.
Preferred sulfonate surfactants are the water-soluble salts, particularly the alkali metal, and alkanolammonium (e.g., monoethanolammonium or triethanolammonium) salts of alkylbenzene sulfonates in which the alkyl group contains from about 10 to about 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, incorporated herein by reference. Especially valuable are linear straight chain alkylbenzene sulfonates in which the average number of carbon atoms in the alkyl group is from about 11 to about 13.
Also useful herein are the water-soluble salts of paraffin sulfonates. olefin sulfonates, alkyl glyceryl ether sulfonates, esters of a-sulfonated fatty acids containing from about 1 to 10 carbon atoms in the ester group. 2-acyloxy-alkane-1-sulfonates containing from about 2 to 9 carbon atoms in the acyl group, and B-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group.
Mixtures of the above-described sulfonates, particularly with the C₁₁-₁₃ linear alkylbenzene sulfonates, can also be used.

Alcohol Ethoxylate Sulfate Surfactant

The present compositions also preferably contain an alcohol polyethoxylate ether sulfate surfactant of the formula RO(C₂H₄O)_mSO₃M, wherein R is a C₁₀-C₁₆ alkyl (preferred) or hydroxyalkyl group, m is from about 0.5 to about 4, and M is a compatible cation. This surfactant preferably represents from about 5% to about 18%. more preferably from about 9% to about 14%, by weight (on an acid basis) of the composition.
Preferred alcohol ethoxylate sulfate surfactants of the above formula are those wherein the R substituent is a C_12-15alkyl group and m is from about 1.5 to about 3. Examples of such materials are C₁₂-₁₅ alkyl polyethoxylate (225) sulfate (C₁₂. 15E225S); C_14-15E_2.25S; C_12-13Et_1.5S; C_14-15E₃S; and mixtures thereof. The sodium, potassium, monoethanolammonium, and triethanolammonium salts of the above are preferred.

Ethoxylated Nonionic Surfactant

The compositions also preferably contain from about 2% to about 15%, more preferably from about 4% to about 12%, by weight of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)-_nOH, wherein R' is a C₁₀-C₁₆ alkyl group or a C_t-C,2 alkyl phenyl group, n is from about 3 to about 9, and said nonionic surfactant has an HLB - (hydrophile-lipophile balance) of from about 10 to about 13. These surfactants are more fully described in U.S. Patents 4,285,841, Barrat et al, issued August 25, 1981, and 4,284,532, Leikhim et al, issued August 18, 1981, both incorporated herein by reference. Particularly preferred are condensation products of C₁₂-C₁₄ alcohols with from about 3 to about 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 herein have an HLB (hydrophilic-lipophilic balance) of from about 5 to about 17, preferably from about 6 to about 13. HLB is defined in detail in Nonionic Surfactants, by M.J. Schick, Marcel Dekker, Inc., 1966, pages 607-613, incorporated herein by reference. Suitable ethoxylated nonionic surfactants herein are as follows:

(1) The polyethylene oxide condensates of alkyl phenols. These compounds include the condensation products of alkyl phenols having an alkyl group containing from about 6 to 12 carbon atoms in either a straight chain or branched chain configuration with ethylene oxide, said ethylene oxide being present in an amount equal to 3 to 25 moles of ethylene oxide per mole of alkyl phenol.

(2) The condensation products of aliphatic alcohols with from about 1 to about 25 moles of ethylene oxide. The alkyl chain of the aliphatic alcohol can either be straight or branched, primary or secondary, and generally contains from about 8 to about 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 with 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 in this type include Tergitol 15-S-9, marketed by union Carbide Corporation, Neodol 45-9, Neodol 23-6.5, Neodol 45-7, and Neodol 45-4, marketed by Shell Chemical Company, and Kyro EOB, marketed by The Proc- ter & Gamble Company.
(3) Mixtures of the above.

Preferred ethoxylated nonionic surfactants are of the formula R¹(OC₂H₄)_nOH, wherein R' is a C,_o-C,6 alkyl group or a C.-C,₂ alkylphenyl group, n is from about 3 to about 9, and said nonionic surfactants has an HLB (hydrophile-lipophile balance) of from about 9 to about 13, preferably from about 10 to about 13.

Cosurfactant

The compositions herein can also contain from 0% to about 15%, preferably from about 0.5% to about 3%, by weight of a cosurfactant 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 are of the formula:
wherein R² is an alkyl or alkyl benzyl group having from about 6 to about 16 carbon atoms in the alkyl chain; each R 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-C₄ alkyl, C,-C4 hydroxyalkyl, benzyl, and hydrogen when y is not 0; R^S is the same as R' or is an alkyl chain wherein the total number of carbon atoms of R² plus R⁵ is from about 8 to about 16; each y is from 0 to about 10 and the sum of the y values is from 0 to about 15; and X is any compatible anion.
Preferred of the above are the alkyl quaternary ammonium surfactants, especially the mono-long chain alkyl surfactants described in the above formula when R^S is selected from the same groups as R'. The most preferred quaternary ammonium surfactants are the chloride, bromide and methylsulfate C_8-16alkyl trimethylammonium salts, C_8-16 alkyl di(hydroxyethyl)methylammonium salts, the C_8-16 alkyl hydroxyethyldimethylammonium salts, C_8- ₁₆alkyloxypropyl trimethylammonium salts, and the C_8-16alkyloxypropyl dihdroxyethylmethylammonium salts. Of the above, the C₁₀-C₁₄ alkyl trimethylammonium salts are preferred, e.g., decyl trimethylammonium methylsulfate, lauryl trimethylammonium chloride, myristyl trimethylammonium bromide and coconut trimethylammonium chloride and methylsulfate.
Under cold water washing conditions, i.e., less than about 65°F (18.3°C), the C_8-10 alkyl trimethylammonium surfactants are particularly preferred since they have lower Kraft boundaries and crystallization temperatures than the longer chain quaternary ammonium surfactants.
Amine surfactants useful herein are of the formula:
wherein the R², R³, R⁴, R⁵ and y substituents are as defined above for the quaternary ammonium surfactants- Particularly preferred are the C₁₂-₁₆ alkyl dimethyl amines.
Amine oxide surfactants useful herein are of the formula:
wherein the R², R³, R⁴, R⁵ and y substituents are also as defined above for the quaternary ammonium surfactants. Particularly preferred are the C₁₂- ₁₆ alkyl dimethyl amine oxides.
Amine and amine oxide surfactants are preferably used at higher levels than the quaternary ammonium surfactants since they are only partially protonated in the present systems. For example, preferred compositions herein can contain from about 0.5% to about 1.5% of the quaternary ammonium surfactant. or from about 1% to about 3% of the amine or amine oxide surfactants.
Amide surfactants herein are of the formula
wherein R" is an alkyl, hydroxyalkyl or alkenyl radical containing from about 8 to about 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 said radicals additionally containing up to about 5 ethylene oxide units, provided at least one of R⁷ and R⁸ contains a hydroxyl group.
Preferred amides are the C₈-C₂₀ fatty acid aI- kylol amides in which each alkylol group contains from 1 to 3 carbon atoms, and additionally can contain up to about 2 ethylene oxide units.
Particularly preferred are the C₁₂-C₁₆ fatty acid monoethanol and diethanol amides.

Fatty Acid

The compositions of the present invention preferably contain from 0% to about 20%, more preferably from about 8% to about 18%, most preferably from about 10% to about 16%, by weight of a saturated fatty acid containing from about 10 to about 14 carbon atoms. In addition, the weight ratio of C₁₀-C₁₂ fatty acid to C,, 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 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 capric, lauric, myristic, coconut and palm kernel fatty acid. Preferred are saturated coconut fatty acids, from about 5:1 to 1:1 (preferably about 3:1) weight ratio mixtures of lauric and myristic acid, mixtures of the above with minor amounts (e.g., 10%-50% of total fatty acid) of oleic acid; and palm kernel fatty acid.

Polycarboxylate Builder

The compositions herein also preferably contain from about 3% to about 20%, more preferably from about 3% to about 6%, more preferably from about 3.5% to about 5% by weight on an acid basis, of a water-soluble polycarboxylate detergent builder material. Polycarboxylate builders are described in U.S. Patent 4,284,532, Leikhim et al, issued August 18, 1981, incorporated herein by reference.
The various aminopolycarboxylates, cycloalkane polycarboxylates, ether polycarboxylates, alkyl polycarboxylates, epoxy polycarboxylates, tetrahydrofuran polycarboxylates, benzene polycarboxylates, and polyacetal polycarboxylates are suitable for use herein.
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, disclosed in U.S. Patent 1,739.942, Eckey, issued March 27, 1956, incorporated herein by reference; the polycarboxylate materials described in U.S. Patent 3,364,103, incorporated herein by reference; and the water-soluble salts of polycarboxylate polymers and copolymers described in U.S. Patent 3,308,067, Diehl, issued March 7, 1967, incorporated herein by reference.
Useful detergent builders also include the water-soluble salts of polymeric aliphatic polycarboxylic acids having the following structural and physical characteristics: (a) a minimum molecular weight of about 350 calculated as to the acid form; (b) an equivalent weight of about 50 to about 80 calculated as to acid form; (3) at least 45 mole percent of the monomeric species having at least two carboxyl radicals separated from each other by not more than two carbon atoms; (d) the site of attachment of the polymer chain of any carboxyl- containing radical being separated by not more than three carbon atoms along the polymer chain from the site of attachment of the next carboxyl- containing radical. Specific examples of such builders are the polymers and copolymers of itaconic acid, aconitic acid, maleic acid, mesaconic acid, fumaric acid, methylene malonic acid, and citraconic acid.
Other suitable polycarboxylate builders include the water-soluble salts, especially the sodium and potassium salts, of mellitic acid, citric acid, pyromellitic acid, benzene pentacarboxylic acid, oxydiacetic acid, carboxymethyloxysuccinic acid, carboxymethyloxymalonic acid, cis-cyclohex- anehexacarboxylic acid, cis-cyclopentanetetracarboxylic acid and oxydisuccinic acid.
Other polycarboxylates for use herein are the polyacetal carboxylates described in U.S. Patent 4,144,226, issued March 13, 1979 to Crutchfield et al, and U.S. Patent 4,146,495, issued March 27, 1979 to Crutchfield et al, both incorporated herein by reference.
Citric acid is a highly preferred polycarboxylate builder.

Neutralization System

The present compositions can contain from about 0 to about 0.04 moles, preferably from about 0.01 to about 0.035 moles, more preferably from about 0.015 to about 0.03 moles, per 100 grams of composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine, and mixtures thereof. Low levels or none of the alkanolamines, particularly monoethanolamine, are preferred to enhance product stability, detergency performance, and odor. The amount of alkanolamine should be minimized for best chlorine bleach compatibility and stability of the soil release component. While the present compositions can contain mixtures of the alkanolamines, best color stability is obtained using single alkanolamines.

Solvent System

The solvent system for the compositions is preferably comprised of ethanol, a polyol, e.g., propanediol, and water. Ethanol is preferably present at a level of from about 2% to about 10%, more preferably from about 5% to about 9%, by weight of the composition.
Any polyol containing from 2 to 6 carbon atoms and from 2 to 6 hydroxy groups can be used in the present compositions. Examples of such polyols are ethylene glycol, propanediol, propylene glycol and glycerine. Propylene glycol is particularly preferred. The polyol preferably represents from about 2% to about 15%, more preferably from about 3% to about 10%, by weight of the composition.
The compositions also preferably contain from about 25% to about 40%, more preferably from about 28% to about 37%, by weight of water.
In addition to the above, the ethanol and polyol together preferably represent from about 8% to about 20%, more preferably about 11 % to about 16%, by weight of the composition. The ethanol, polyol and water preferably total from about 35% to about 55%, more preferably about 40% to about 50%, by weight of the composition.
The compositions of the present invention preferably have the following limits, in which all percentages and ratios are calculated on an acid basis where anionic materials are involved. The sulfonate, alcohol ethoxylate sulfate, ethoxylated non- ionic and quaternary ammonium, amine, amide and/or amine oxide surfactants, together, preferably represent from about 20% to about 40%, more preferably from about 23% to about 30%, by weight of the composition.
The fatty acid and polycarboxylate builder together preferably represent from about 5% to about 30%, more preferably from about 10% to about 25%, by weight of the composition. In addition, the fatty acid, polycarboxylate builder and above surfactants preferably represent. a total of from about 33% to about 50%, more preferably from about 36% to about 48%, by weight of the composition.
Finally, all of the above components are selected to provide an isotropic liquid detergent at 55°F (12.8°C), preferably at 50°F (10°C). The components are also selected to provide an initial pH of from about 7.5 to about 9.0, preferably from about 7.8 to about 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 herein include enzymes, enzyme stabilizing agents. polyacids, soil removal agents, anti-redeposition agents suds regulants, hydrotropes, opacifiers, antioxidants, bactericides, dyes, perfumes, and brighteners described in the U.S. Patent 4,285,841, Barrat et al, issued August 25, 1981, incorporated herein by reference. Such optional components generally represent less than about 15%, preferably from about 2% to about 10%, by weight of the composition.
Enzymes are highly preferred optional ingredients and are incorporated in an amount of from about 0.025% to about 2%, preferably from about 0.05% to about 1.5%. Preferred proteolytic enzymes should provide a proteolytic activity of at least about 5 Anson units (about 1,000,000 Delft units) per liter, preferably from about 15 to about 70 Anson units per liter, most preferably from about 20 to about 40 Anson units per liter. A proteolytic activity of from about 0.01 to about 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 adapted 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 tradenames SP-72 ("Esperase") manufactured and sold by Novo Industries, A/S, 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 disclosure of suitable enzymes can be found in U.S. Patent 4,101.457, Place et al, issued July 18, 1978, incorporated herein by reference.
When enzymes are incorporated in the detergent compositions of this invention, they are desirably stabilized by using a mixture of a short chain carboxylic acid salt and calcium ion, such as disclosed in U.S. Patent 4.318.818, Letton et al, issued March 9, 1982. incorporated herein by reference.
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 at a level from about 0.25% to about 10%, preferably from about 0.3% to about 3%, more preferably from about 0.5% to about 1.5%. Any water-soluble calcium salt can be used as a source of calcium ion, including calcium acetate, calcium formate and calcium propionate. The composition should contain from about 0.1 to about 30 millimoles of calcium ion per liter, preferably from about 0.5 to about 15 millimoles of calcium ion per liter. When materials are present which complex calcium ion, it is necessary to use high levels of calcium ion so that there is always some minimum level available for the enzyme.
Enzymes are preferably stabilized in the present compositions by the addition of from about 025% to about 10%, preferably from about 0.5% to about 5%, more preferably from about 0.75% to about 3%, by weight of boric acid or a compound capable of forming boric acid in the composition - (calculated on the basis of the boric acid). Boric acid is preferred, although other compounds such as boric oxide, 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, butane boronic acid, and p-bromo phenylboronic acid) can 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 less than that obtained using boric acid alone.
Preferred compositions also contain from about 0.01% to about 1% of a polyacid or salt thereof, to enhance pretreatment performance. Preferred polyacids for use herein are ethylenediamine tetramethylenephosphonic acid, diethylene triamine pentamethylenephosphonic acid, and diethylenetriamine pentaacetic acid, or the salts thereof. These polyacids/salts are preferably used in an amount from about 0.1% to about 0.8%.
Preferred compositions herein further contain from about 0.5% to about 3%, preferably from about 1% to about 2%, by weight of a highly ethoxylated polyethyleneamine or polyethyleneimine soil removal and antiredeposition agent. A particularly preferred species of the like soil removal and anti-redeposition 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 1

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

A compound having a range of copolymers of the formula

in which about 20% by weight of the material has a value of u higher than 5 is dissolved at about 15% level in anhydrous ethanol; cooled to about 10°C; the insoluble portion (~ 20%) is filtered; enough ethanol is distilled to reduce the ethanol level to within the level in the following formula; and the compound is added to the formula.

EXAMPLE II

A liquid detergent composition of the present invention is as follows:
A compound having a range of copolymers of the formula:

in which about 20% by weight of the material has a value of u higher than 5 is dissolved at about 15% level in anhydrous ethanol; cooled to about 10°C; the insoluble portion (~20%) is filtered; enough ethanol is distilled to reduce the ethanol level to within the level in the following formula; and the compound is added to the formula.

Claims

1. A heavy-duty liquid detergent composition comprising, by weight:

(a) from about 10% to about 35%, of an anionic surfactant on an acid basis;

(b) from 0% to about 15% of an ethoxylated nonionic surfactant of the formula R¹(OC₂H₄)_nOH, wherein R' is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkyl phenyl group, n averages from about 3 to about 9, and said nonionic surfactant has an HLB of from about 10 to about 13;

(c) from about 0% to about 15% of a cosurfactant selected from the group consisting of:

(i) quaternary ammonium surfactants having the formula:

wherein R² is an alkyl or alkyl benzyl group having from about 6 to about 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-C₄ alkyl. C₁-C₄ hydroxyalkyl, benzyl, and hydrogen when y is not 0: R⁵ is the same as R⁴ or is an alkyl chain wherein the total number of carbon atoms of R² plus R^S is from about 8 to about 16: each y averages from 0 to about 10 and the sum of the y values is from 0 to about 15; and X is any compatible anion;

(ii) amine surfactants having the formula:

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

(iii) amine oxide surfactants having the formula:

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

(iv) an amide surfactant of the formula:

wherein R⁶ is an alkyl, hydroxyalkyl or alkenyl radical containing from about 8 to about 20 carbon atoms, and R⁷ and R⁸ 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 about 5 ethylene oxide units; and

(v) mixtures thereof;

(d) from about 5% to about 30% of detergent builder;

(e) a neutralization system;

(f) an aqueous solvent system;

(g) from about 0.25% to about 4% of a soil release component which comprises an effective amount of a soil release compound having the formula:

wherein each R' moiety is a phenylene moiety, each R² is an ethylene or a 1,2-propylene moiety; each n averages from about 10 to about 50, each X is H, or an alkyl or an acyl radical containing from 1 to about 4 carbon atoms, and u is a range of values from about 3 to about 5, with only minimal amounts of compounds being present in which u is 6 or more.

2. The composition of Claim 1 wherein in component (g), n ranges from about 10 to about 25 and from about 90% to 100% of the R² moieties are 1,2-propylene moieties.

3. The composition of Claim 2 wherein X is an alkyl radical containing from about 1 to 2 carbon atoms.

4. The composition of Claim 2 wherein component

(g) is a fraction of polymers soluble in absolute ethanol at a temperature of from about 10°C to about 15°C.

5. The composition of Claim 1 wherein component (g) is a fraction of polymers soluble in absolute ethanol at a temperature of from about 10°C to about 15°C.

6. The composition of Claim 5 wherein the anionic surfactant comprises:

(a) from about 5% to about 15%, on an acid basis, of a sulfonate surfactant containing a C,_o-C₁₆ alkyl or alkenyl group; and

(b) from about 8% to about 18%, an 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 about 0.5 to about 4, and M is a compatible cation; and

(c) from about 2% to about 15% of an ethoxylated nonionic surfactant of the formula R'-(OC₂H₄)_nOH, wherein R' is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkyl phenyl group, n is from about 3 to about 9, and said nonionic surfactant has an HLB of from about 10 to about 13.

7. The composition of Claim 5 wherein the anionic surfactant comprises:

(a) from about 5% to about 15%, on an acid basis, of a sulfonate surfactant containing a C,_o-C,₆ alkyl or alkenyl group; and

(b) from about 1% to about about 4%, on an acid basis, of a C₁₀-C₁₆ alkyl sulfate; and

(c) from about 2% to about 15% of an ethoxylated nonionic surfactant of the formula R'-(OC₂H₄)_nOH, wherein R' is a C₁₀-C₁₆ alkyl group or a C₈-C₁₂ alkyl phenyl group, n is from about 3 to about 9, -and said nonionic surfactant has an HLB of from about 10 to about 13.

8. The composition of Claim 5 wherein the sulfonate surfactant is a C₁₁-C₁₃ linear alkylbenzene sulfonate; in the alcohol ethoxylate sulfate surfactant, R is a C₁₂-C₁₅ alkyl group and m is from about 1.5 to about 3; and in the ethoxylated nonionic surfactant, R is a C₁₂-C₁₄ alkyl group and n is from about 3 to about 7.

9. The composition of Claim 8 comprising from about 0.5% to about 3% of the cosurfactant, which is a C₁₀-C₁₄ alkyl trimethylammonium chloride, bromide or methylsulfate.

10. The composition of Claim 8 wherein the builder comprises a polycarboxylate builder.

11. The composition of Claim 8 comprising from about 6% to about 10% of the sulfonate surfactant, from about ;9% to about 14% of the alcohol ethoxylate sulfate surfactant, from about 4% to about 10% of the ethoxylated nonionic surfactant, and from about 0.5% to about 1.5% of the cosurfactant, which is a C₁₀-C₁₄ alkyl trimethylammonium chloride, bromide or methylsulfate.

12. The composition of Claim 11 in which the builder comprises from about 10% to about 16% of saturated fatty acid and from about 3% to about 6% of citric acid.

13. The composition of Claim 12 comprising from 0 to about 0.035 moles per 100 grams of composition of the alkanolamine, which is monoethanolamine.

14. The composition of Claim 13 comprising from about 5% to about 9% of ethanol, from about 3% to about 10% of the polyol, which is propylene glycol, and from about 28% to about 37% of water.

15. The composition of Claim 14 having an initial pH of from about 7.8 to about 9.0 at a concentration of 10% by weight in water at 68°F (20°C).

16. The process of preparing a soil release component having the formula:

in which each X is selected from the group consisting of hydrogen, alkyl groups containing from one to about four carbon atoms, acyl groups containing from 2 to about four carbon atoms, n averages from about 10 to about 50, and there is substantially no material in which u is greater than five, comprising the step of dissolving a soil release component comprising the desired material and a substantial amount of material in which u is greater than five in absolute ethanol at a temperature of from about 10°C to about 15°C and separating the precipitating material.

17. The ethanol soluble soil release component obtained by the process of Claim 16.

18. The component of Claim 17 wherein n ranges from about 10 to about 25 and from about 90% to 100% of the R² moieties are 1,2-propylene moieties.

19. The component of Claim 17 wherein each X is an alkyl group containing from about 1 to about 2 carbon atoms.

20. The component of Claim 17 comprising essentially material wherein u is 3 to 5.