GB2197340A - Liquid laundry detergent compositions - Google Patents

Abstract

Heavy-duty liquid detergent compositions contain sulfonate surfactant, ethoxylated nonionic surfactant, alkyl or alkenyl succinate and citrate builders, potassium and sodium ions, an absence or a low level of alkanolamine, and a solvent system comprising propylene glycol and water. The compositions are isotropic liquids providing a high level of detergency performance and chlorine bleach compatibility. The compositions may also contain an alkyl amine-anionic surfactant ion-pair complex as a fabric care agent, in the form of a stable homogeneous suspension.

Description

SPECIFICATION Stable liquid detergent compositions Technical Field The present invention relates to heavy-duty liquid detergent compositions containing sulfonate surfactant, ethoxylated nonionic surfactant, alkyl or alkenyl succinate and citrate builders, a.

neutralization system comprising potassium and sodium ions and, preferably, a low level of alkanolamine, and a solvent system comprising propylene glycol and water. The compositions are stable isotropic liquids providing a high level of detergency performance and good chlorine bleach compatibility. The compositions preferably also contain an alkyl amine-anionic surfactant ion-pair complex which imparts fabric care (i.e., softening and/or static control) benefits throughthe-wash without significantly impairing cleaning performance. Such compositions preferably are in the form of stable homogeneous suspensions.

Background of the Invention 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. Yet, isotropic liquid detergents are desired for both consistency of performance and aesthetic reasons. The compositions should be isotropic as made, e.g., at about 68"F (20"C), and preferably remain isotropic during shipping and storage, where temperatures ranging from 90"F (32.2"C) or higher to 55"F (12.8"C) or lower are often encountered.They should also be formulated to recover, after freezing and thawing, to an isotropic phase prior to consumer use.

Liquid detergents often contain high levels of alkanolamines to enhance performance and product stability. However, alkanolamines readily react with and destroy chlorine bleaches. Consumers who add chlorine bleaches to wash solutions containing alkanolamine-based detergents consequently do not obtain optimum bleaching performance.

Heavy-duty liquid detergent compositions that are isotropic liquids providing a high level of detergency performance and improved chlorine bleach compatibility are disclosed in U.S. Patent 4,507,219, Hughes, isssued March 26, 1985. The compositions contain sulfonate and alcohol ethoxylate sulfate anionic surfactants, ethoxylated nonionic surfactant, optional quaternary ammonium, amine or amine oxide surfactants, saturated fatty acid, polycarboxylate builder, a neutralization system comprising sodium, potassium and, preferably, low levels of alkanolamines, and a solvent system comprising ethanol, polyol and water.

Numerous attempts have also been made to formulate laundry detergent compositions which simultaneously provide good cleaning and fabric care performance. Attempts have been made to incorporate cationic fabric softeners in anionic surfactant-based detergent compositions employing various means of overcoming the natural antagonism between the anionic and cationic surfactants. For instance, U.S. Patent 3,936,537, Baskerville et al., issued February 3, 1976, discloses detergent compositions comprising organic surfactant, builders, and, in particulate form, a quaternary ammonium softener combined with a poorly water-soluble dispersion inhibitor which inhibits premature dispersion of the cationic in the wash liquor. Even in these compositions, some compromise between cleaning and softening effectiveness has to be accepted.

Other laundry detergent compositions have employed tertiary amines along with anionic surfactants to act as fabric softeners. British Patent 1,514,276, Kengon, published June 14, 1978, employs certain tertiary amines with two long chain alkyl or alkenyl groups and one short chain alkyl group. The amines are useful as fabric softeners in detergent compositions when their isoelectric point is such that they are present as a dispersion of negatively charged droplets in the normally alkaline wash liquor, and are present in a more cationic form at the lower pH of a rinse liquor, and so become substantive to fabrics. The use of such amines, among others, in detergent compositions has also been previously disclosed in British Patent 1,286,054, assigned to Colgate-Palmolive, published August 16, 1972, British Patent 1,514,276, assigned to Unilever, published June 14, 1978, and in U.S.Patent 4,375,416, Crisp et all, issued March 1, 1983.

Another approach to provide anionic detergent compositions with fabric softening ability has been the use of smectite-type clays, as described in U.S. Patent 4,062,647, Storm et all, issued December 13, 1977. These compositions, although they clean well, require large contents of clay for effective softening. The use of clay together with a water-insoluble cationic compound in an electrically conducting metal salt as a softening composition adapted for use with anionic, nonionic, zwitterionic and amphoteric surfactants has been described in British Patent 1,483,627, assigned to Procter & Gamble, published August 24, 1977.

British Patent Applications 1,077,103 and 1,077,104, assigned to Bayer, published July 26, 1967, disclose amine-anionic surfactant ion-pair complexes useful as antistatic agents. The complexes are applied directly to the fabric from an aqueous carrier. There is no suggestion in either of these references that such complexes could be added to detergent composition to impart fabric care benefits through-the-wash. In fact, such complexes could not be delivered through-the-wash.

Fatty acid-amine ion-pair complexes in granular detergents are disclosed in European Patent Application 0,133,804, Burckett-St.Laurent et al., published June 3, 1985. While these compositions deliver fabric conditioning, the alkyl amine-anionic surfactant complexes of the present invention deliver superior antistatic performance.

It is therefore an object of the present invention to provide a heavy-duty liquid detergent composition in a stable isotropic form which exhibits good cleaning performance and bleach compatibility.

It is another object of the present invention to provide a heavy-duty liquid detergent composition in the form of a stable homogeneous suspension comprising the above composition and an alkyl amine-surfactant ion-pair complex which delivers through-the-wash fabric care benefits without significantly impairing cleaning performance.

Summary of the Invention The present invention encompasses a heavy-duty liquid detergent composition comprising, by weight: (a) from about 10% to about 30%, on an acid basis, of a sulfonate surfactant containing a C,O-C16 alkyl or alkenyl group; (b) from about 1% to about 15% of an ethoxylated nonionic surfactant of the formula R'(OC2H4)nOH, wherein R1 is a C10-C16 alkyl group or a C8-C,2 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 7% to about 20%, on an acid basis, of a C12-C14 alkyl of alkenyl succinate builder material; (d) from about 1% to about 7%, on an acid basis, of a citrate builder material;; (e) from about 0 to about 0.04 moles per 100 grams of composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine and triethanolamine; (f) potassium and sodium ions in a molar ratio of potassium to sodium of from about 1.4 to about 5.0; (g) from about 5% to about 20% of propylene glycol; and (h) from about 15% to about 45% water; said composition containing from about 15% to about 40% of (a) and (b); from about 10% to about 25% of (c) and (d); from about 30% to about 55% of (a), (b), (c) and (d); and from about 30% to about 55% (g) and (h); the weight ratio of (a) to (b) being from about 1 to about 10; and all of said components being selected to provide an isotropic liquid at 200C having an initial pH of from about 6.0 to about 10.0 at a concentration of about 10% by weight in water at 20"C.

Preferred compositions further comprise an alkyl amine-anionic surfactant ion-pair complex that provides fabric care benefits, and optional detergent ingredients, and are in the form of a stable homogeneous suspension.

Detailed Description of the Invention The liquid detergents of the present invention contain sulfonate anionic surfactant, ethoxylated nonionic surfactant, alkyl or alkenyl succinate and citrate builders, a neutralization system comprising potassium and sodium ions and, preferably, a low level of alkanolamine, and a solvent system comprising propylene glycol and water.

The compositions herein are formulated to provide a high level of detergency performance under a wide variety of laundering conditions. They also provide good chlorine bleach compatibility due to the limited amount of alkanolamine. Since the compositions contain a relatively high level of active components and little or no alkanolamine to enhance product stability, the types, levels and ratios of the components must be carefully balanced to provide isotropic liquids as made and preferably at storage temperatures as high as 90"F (32.2 C) and as low as 55"F (12.82C). 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).

In order to meeet these stability constraints, the present compositions require a neutralization system comprising potassium and sodium ions in a specified molar ratio. Greater sodium neutralization than required results in gelling of the product during the addition of the succinate builder material, whereas greater potassium neutralization results in an unacceptably hazy product. The total level of organic and inorganic bases must also be selected to provide a sufficiently high product pH to obtain a wash pH desired for detergency performance, without the pH being so high that pH sensitive stain removal and enzyme stability are compromised.

The compositions also require a solvent system comprising propylene glycol and water, in an amount sufficient to prevent organic phase separation (i.e., keep poorly-soluble surfactants in solution).

Sulfonate Surfactant The detergent compositions herein contain from about 10% to about 30%, preferably from about 15% to about 25%, by weight (on an acid basis) of a water soluble anionic sulfonate surfactant containing a C,O-C,6 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 ss-alkyloxy alkane sulfonates containing from about 1 to 3 carbon atoms in the alkyl group.

Mixtures of the above-described sulfonates, particularly with the C1113 linear alkylbenzene sulfonates, can also be used.

Ethoxylated Nonionic Surfactant The compositions also contain from about 1% to about 15%, preferably from about 5% to about 12%, by weight of an ethoxylated nonionic surfactant of the formula R'(OC2H4)nOH, wherein R' is a C,O-C,6 alkyl group or a C8-C,2 alkyl phenyl group, n averages 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 C,2-C14 alcohols with from about 3 to about 7 moles of ethylene oxide per mole of alcohol, e.g., Cl2-Cl3 alcohol condensed with about 6.5 moles of ethylene oxide per mole of alcohol.

Succinate Builder The detergent compositions herein also contain from about 7% to about 20%, preferably from about 10% to about 15%, by weight on an acid basis, of a succinate builder of the general formula R-CH(COOH)CH,(COOH), wherein R is Cl2-Cl4 alkyl or alkenyl group.

These succinate builders are preferably used in the form of their water-soluble salts, including the sodium, potassium, ammonium and alkanolammonium salts (e.g., mono-, di-, or tri-ethano ammonium Specific examples of succinate builders include: lauryl succinate, myristyl succinate, 2-dodecenyl succinate (preferred) and 2-tetradecenyl succinate.

Citrate Builder The compositions further contain from about 1% to about 7%, preferably from about 2% to about 5.5%, by weight on an acid basis, of a citrate (preferably in the form of an alkali metal or alkanolammonium salt) builder material. This material is generally added to the compositions herein as citric acid, but can be added in the form of a fully neutralized salt.

Neutralization System The present compositions can contain grom 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 of the alkanolamines, particularly monoethanolamine, are preferred to enhance product stability and detergency performance. However, the amount of alkanolamine should be minimized for best chlorine bleach compatibility.

In addition, the compositions contain potassium and sodium ions, in a molar ratio of potassium to sodium of from about 1.4 to about 5.0, preferably from about 1.5 to about 2.5, and at a level sufficient to neutralize the anionic species and provide the desired product pH.

Solvent System The solvent system for the compositions is comprised of propylene glycol and water.

The propylene glycol (1,2-propane diol is particularly preferred) represents from about 5% to about 20%, preferably from about 8% to about 18%, by weight of the composition.

The compositions also contain from about 15% to about 45%, preferably from about 20% to about 40%, by weight of water.

In addition, the propylene glycol and water represent from about 30% to about 55%, preferably about 35% to about 50%, by weight of the composition.

The compositions of the present invention are further constrained by the following limits, in which all percentages and ratios are calculated on an acid basis where anionic materials are involved. The sulfonate and ethoxylated nonionic surfactants, together, represent from about 15% to about 40%, preferably from about 20% to about 35%, by weight of the composition.

The weight ratio of the sulfonate surfactant to the ethoxylated nonionic surfactant should also be from about 1 to about 10, preferably from about 1.5 to about 5.

The succinate and citrate builders together represent from about 10% to about 25%, preferably from about 13% to about 20%, by weight of the composition. In addition, the above builders and surfactants represent a total of from about 30% to about 55%, preferably from about 40% to about 50%, by weight of the composition.

Finally, all of the above components are selected to provide an isotropic liquid detergent at 68"F (20"C), and preferably at 90"F (32.2"C) and at 55"F (12.8"C). The components are also selected to provide an initial pH of from about 6.0 to about 10.0, preferably from about 7.0 to about 9.0, at a concentration of 10% by weight in water at 68"F (20"C).

Optional Components The liquid detergents herein can contain other surfactants and builders, and other components known for use in detergent compositions, including enzymes, enzyme stabilizing agents, polyacids, soil removal agents, antiredeposition agents, suds regulants, hydrotropes, opacifiers, antioxidants, bactericides, dyes, perfumes, and brighteners, such as those described in the U.S. Patent 4,285,841, Barrat et al, issued August 25, 1981, and in U.S. Patent 4,507,219, Hughes, issued March 26, 1985, both 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.

Particularly preferred compositions herein contain from about 0.1% to about 10%, preferably from about 0.5% to about 8%, more preferably from about 1% to about 6%, by weight of relatively water-insoluble particles comprising an alkyl amine-anionic surfactant ion-pair complex as a fabric care agent.

The complex can be represented by the following formula:

wherein Rl and R2 can independently be C,6 to C20 alkyl or alkenyl groups. Preferred amines used to form these complexes are water-insoluble and include hydrogenated or unhydrogenated ditallow amine. A represents an anionic surfactant selected from the group consisting of alkyl sulfonates, aryl sulfonates, alkylaryl sulfonates, and paraffin sulfonates. Preferred anionic surfactants are C, to C20 linear alkylbenzene sulfonates and C,2 to C,8 paraffin sulfonates. Mixtures of these ion pairs can also be used.

It has been found that in order for these ion-pair complex particles to impart their fabric care benefits they must have an average particle diameter of from about 10 to about 300 microns, preferably from about 10 to about 250 microns, more preferably from about 10 to about 200 microns, and most preferably from about 10 microns to about 150 microns. The term "average particle diameter" represents the mean particle size diameter of the actual particles of a given material. The mean is calculated on a weight percent basis. The mean is determined by conventional analytical techniques such as, for example, laser light diffraction or microscopic determination utilizing a scanning electron microscope. Preferably, greater than 50% by weight, more preferably greater than 60% by weight, and most preferably greater than 70% by weight, of the particles have actual dimaters which fall within the range of from about 10 to about 300 microns, preferably from about 10 to about 250 microns, more preferably from about 10 to about 200 microns, and most preferably from about 10 microns to about 150 microns.

Starting alkyl amines are of the formula:

wherein R, and R2 are C,6 to C20 alkyl or alkenyl groups, preferably C,6 to C,8 alkyl or alkenyl, and most preferably C,6 to C,8 alkyl. Suitable non-limiting examples of starting amines include hydrogenated ditallow amine, unhydrogenated ditallow amine, dipalmityl amine, distearyl amine, diarachidyl amine, palmityl stearyl amine, palmityl arachidyl amine and stearyl arachidyl amine.

Most preferred are the hydrogenated and unhydrogenated forms of ditallow amine.

The anionic surfactants (A) useful in the ion-pair complex of present invention are the C, to C20 alkyl sulfonates, aryl sulfonates, C, to C20 alkylaryl sulfonates and C,2 to C,8 paraffin sulfonates.

These classes of anionic surfactants have been fully described above.

Particularly preferred are the linear C, to C20 alkylaryl sulfonates and more particularly preferred are the linear C4-C,3 alkylbenzene sulfonates. Most preferred are the linear C6 to C,3 alkyl benzene sulfonates.

Non-limiting examples of ion-pair complexes suitable for use in the present invention include: ditallow amine (hydrogenated or unhydrogenated) complexed with a linear C1-C20 alkyl benzene sulfonate (LAS), dipalmityl amine complexed with a C,-C20 LAS, distearyl amine complexed with a C,-C20 LAS, diarachidyl amine complexed with a C,-C20 LAS, palmityl stearyl amine complexed with a C,-C20 LAS, parlmityl arachidyl amine complexed with a :::,-C20 LAS, stearyl arachidyl amine complexed with a C,-C20 LAS, ditallow amine (hydrogenated or unhydrogenated) complexed with a C1-C20 alkyl sulfonate (AS), dipalmityl amine complexed with a C,-C20 AS, distearyl amine complexed with a C,-C20 AS, diarachidyl amine complexed with a C,-C20 AS, palmityl stearyl amine complexed with a C,-C20 AS, parlmityl arachidyl amine complexed with a C,-C20 AS, stearyl arachidyl amine complexed with a Ct-C20 AS, ditallow amine (hydrogenated or unhydrogenated) complexed with a C12-C,8 paraffin sulfonate (PS), dipalmityl amine complexed with a C,2-C,8 paraffin sulfonate PS, distearyl amine complexed with a C,2-C,8 PS, diarachidyi amine complexed with a C,2-C,8 PS, palmityl stearyl amine complexed with a C12-C18 PS, palmityl arachidyl amine complexed with a C12-C,8 PS, stearyl arachidyl amine complexed with a C12-C18 PS, and mixtures of these ion-pair complexes.

More preferred are complexes formed from the combination of ditallow amine (hydrogenated or unhydrogenated) complexed with C,-C20 LAS, C,-C20 AS, or C,2-C,8 PS. Even more preferred are those complexes formed from ditallow amine (hydrogenated or unhydrogenated) complexed with a C,-C20 LAS. Most preferred are complexes formed from ditallow amine (hydrogenated or unhydrogenated) complexed with C6-C,3 LAS.

The amine-surfactant complexes herein are prepared separately from the balance of the composition, and are preferably then added to the detergent ingredients in such a way as to insure that the complexes are homogeneously dispersed therein. The amine and surfactant components are combined in a molar ratio of alkyl amine to surfactant ranging from about 1:10 to about 10:1, preferably from about 1:1 to about 9:1. This can be accomplished by any of a variety of means, including but not limited to, preparing a melt of the anuionic surfactant and the amine and then dispersing the molten complex into the balance of the detersive ingredients, with constant agitation.

Alternatively, the above molten complex can be allowed to cool, preferably while stirring the molten mixture.

Other methods of forming the ion-pair complex include dissolving the components in an organic solvent, or by heating the amine to a liquid state and then adding this molten amine component to a heated acidified aqueous solution of the anionic surfactant, and then extracting the ion-pair complex by using a solvent, such as chloroform.

The complexing of the amine and the anionic surfactant results in an entity (ion-pair) which is chemically distinct from either of the two starting materials.

The desired particle sizes can be achieved by, for example, mechanically grinding the resulting ion-pair complex in blenders (e.g., an OsterR blender) or in large scale mills (e.g., a Wiley R Mill) to the desired particle size range.

Such factors as the type of amine employed and the ratio of the amine-surfactant components can affect the physical properties of the resulting complex. Complexes which are gelatinous at room temperature can be mechanically ground to achieve the desired particle size after flash freezing by using, for example, liquid nitrogen.

The complexes are further characterized by their melting points, which generally iie in the range of from about 10 C to about 75"C. A particularly preferred complex, which comprises a hydrogenated ditallow amine complexed with a linear C6 to C13 alkyl benzene sulfonate surfactant in a 1:1 molar ratio has a melting point of about 20"C.

It has been found that these fabric care agents, unlike those of the prior art, can be incorporated into the detergent compositions of the present invention with little, if any, detrimental effect on cleaning, These detergent compositions provide fabric care benefits across a variety of laundering conditions, that is, machine or hand washing and machine drying, and also machine or hand washing and line drying. Additionally, these same fabric care agents can be used with a variety of surfactant systems.

Preferably, the compositions of the present invention contain a stabilizing agent to maintain the fabric care agent uniformly dispersed in the liquid detergent. Otherwise, density differences between the insoluble particles and the liquid base detergent can cause eventual particle settling or creaming.

The choice of the stabilizing agent for the present compositions depends upon factors such as the type and level of solvent ingredients in the composition.

Suitable suspending agents include various clay materials, such as montmorillonite clay, quaternized monomorillonite clays (e.g. Bentone 14, available from NL Industries), polysaccharide gums (e.g. xanthan gum available from Kelco Division of Merck & Co., Inc.), any of several long-chain acyl derivative materials or mixtures of such materials, diethanolamide of a long-chain fatty acid (e.g., PEG 3 lauramide), block polymers of ethylene oxide and propylene oxide (such as Pluronic F88 offered by BASF Wyandotte), sodium chloride, ammonium xylene sulfonate, sodium sulfate, and polyvinyl alcohol. Other suspending agents found useful are alkanol amides of fatty acids, having from about 16 to about 22 carbon atoms, preferably from about 16 to about 18 carbon atoms.Preferred alkanol amides are stearic monoethanolamide, stearic diethanolamide, stearic monoisopropanolamide and stearic monoethanolamide stearate. Other long-chain acyl derivatives include long-chain esters of long-chain alkanol amides (e.g., stearamide DEA distearate, stearamide MEA stearate).

The most preferred suspending agent for use in the present invention is the quaternized montmorillonite clay.

This suspending agent is preferably present at a level of from about 0.1% to about 10.0%, preferably from about 0.5% to about 1.5%, by weight of the detergent composition.

The compositions herein can also contain polymeric soil release agents, including cellulosic derivatives such as hydroxyether cellulosic polymers, copolymeric blocks of ethylene terephthalate, and cationic guar gums, and the like.

The cellulosic derivatives that are functional as soil release agents are commercially available and include hydroxyethers of cellulose such as MethocelR (Dow) and cationic cellulose ether derivatives such as Polymer JR-124R, JR-400R, and JR-30MR (Union Carbide). See also U.S.

Patent 3,928,213 to Temple et al., issued December 23, 1975, which is incorporated by reference.

Other effective soil release agents are cationic guar gum such as Jaguar PlauR (Stein Hall) and Gendrive 458R (General Mills).

Preferred cellulosic soil release agents for use herein are selected from the group consisting of methyl cellulose; hydroxypropyl methylcellulose; hydroxybutyl methylcellulose; or a mixture thereof, said cellulosic polymer having a viscosity in aqueous solution at 20"C of 15 to 75,000 centipoise.

A more preferred soil release agent is a copolymer having random blocks of ethylene terephthalate and polyethylene oxide (PEO) terephthalate. More specifically, these polymers are comprised of repeating units of ethylene terephthalate and PEO terephthalate in a mole ration of ethylene terephthalate units to PEO terephthalate units of from about 25:75 to about 35:65, said PEO terephthalate units containing polyethylene oxide having molecular weights of from about 300 to about 2000. The molecular weight of this polymeric soil release agent is in the range of from about 25,000 to about 55,000. See U.S. Patent 3,959,230 to Hays, issued May 25, 1976, which is incorporated by reference, See also U.S. Patent 3,893,929 to Basadur issued July 8, 1975 (incorporated by reference) which discloses similar copolymers.Surprisingly, it has been found that these polymeric soil release agents balance the distribution of the fabric care agent of the present invention against a broad range of synthetic fabrics such as polyesters, nylons, polycottons and acrylics. This more uniform distribution of the fabric care agent can result in improved fabric care qualities.

Another preferred polymeric soil release agent is a crystalizable polyester with repeat units of ethylene terephthalate units containing 10-15% by weight of ethylene terephthalate units together with 90-80% by weight of polyoxyethylene terephthalate units, derived from a polypoxyethylene glycol of average molecular weight 300-5,000, and the mole ratio of ethylene terephthalate units to polyoxyethylene terephthalate units in the crystallizable polymeric compound is between 2:1 and 6:1. Examples of this polymer include and commercially available material ZelconR 5126 (from Dupont) and MileaseR (from ICI).

Particularly preferred polymers herein and methods of their preparation are more fully described in European Patent Application 185,417, Gosselink, published June 25, 1986, which is incorporated herein by reference, If utilized, these soil release agents will generally comprise from about 0.05% to about 5.0% by weight of the detergent compositions herein, more preferably from about 0.2% to about 3.0% by weight of such compositions.

While the above compositions containing the ion-pair complex can contain other detergent surfactants, they preferably contain less than about 5%, preferably less than about 3%, most preferably less than about 1%, by weight of anionic sulfate and ethoxy sulfate surfactants, for example, those of the formula RO(C2H40)rnSO3M, where R is a C10-C,6 alkyl or hydroxyalkyl group, m is O or averages up to about 4, and M is a compatible cation. Most preferably, the compositions are substantially free of such sulfate surfactants, which inhibit deposition of the above fabric care active.

The compositions herein can contain up to about 2% by weight of ethanol as an additional solubilizing agent. However, the compositions do not require ethanol for phase stability, and preferably contain little or no ethanol (e.g., less than about 1 % by weight) for compatibility with the above fabric care active, which can be solubilized by ethanol. They preferably are substantially free of ethanol.

The following examples iilustrate the compositions of the present invention.

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

EXAMPLE I The following composition is prepared by adding the components to a mixing tank in the order listed with continuous mixing.

Wt.% in Actual Wt. Wt.% Finished Components Assays Added (lb) Added Product 2 Water 100.00 115.83 5.26 24.11 1,2=Propanediol 100.00 318,78 14.49 14.49 Sodium hydroxide 50.00 106,48 4,84 2.42 Potassium hydroxide 45.00 262,46 11.93 5.802 C12-13 alcohol poly ethoxylate (6.5)a 100.00 147.40 6.70 8.70 Sodium diethylene- triamine penta acetate 41.00 15,56 0.71 0,29 C12 alkenyl succinic anhydride 100.00 246.62 11.21 11.21 Calcium formate 10.00 22.00 1.00 0.10 Sodium formate 30.00 36.67 1.67 0.50 C11.4 linear alkyl benzene sulfonic acid 96.00 394.17 17.92 17,20 Citric acid 50.00 153.12 6,96 3.48 Monoethanolamine 100.00 20.46 0.93 1,93 Brightener 3,90 114.47 5.20 0.20 TEPA-E15-18** 80.00 39.88 1.81 1,45 (Base product total) (1993.88) (90.63) Potassium hydroxide 45.00 21.10 0.96 - (Total molar K+:Na+) (1.7) Soil release polymer*** 100.00 21.34 0.97 0.97 Protease enzyme = 12.76 0.58 (2.5 AU/g) Amylase enzyme - 6.60 0.30 (155 AMU/mg) Bentone 14 clay 100.00 15.84 0.72 0.72 DTA/LAS complex 100.00 116.82 5.31 5.31 Dye 1.00 6.60 0.30 0.01 Perfume 100.00 5.06 0.23 0.23 (Finished product total) (2200.00) (100.00) Balance to 1008 is water unless otherwise noted.

From more than one source.

3Balance also includes 19.23% monoethanolamine and 38.46% C12-13 alcohol polyethoxylate (6.5)*.

tAlcohol and monoethoxylated alcohol removed.

**Tetraethylene pentaimine ethoxylated with 15-18 moles (avg.) of ethylene oxide at each hydrogen site on each nitrogen.

***Poly (terephthalate propyleneglycol ester) ethoxylated with about 30 moles of ethylene oxide.

The composition has a pH of about 14 and a temperature of about 37.8"C when the C12 alkenyl succinic anhydride is added. (The anhydride is used because it is easier to handle and provides lighter colored product than the corresponding acid.) The temperature is allowed to rise up to about 71.1"C with moderate agitation. The high temperature, high pH and substantial water availability are designed to drive the hydrolysis and neutralization of the anhydride to completion. This is accomplished prior to the addition of the monoethanolamine to avoid reaction between the monoethanolamine and the anhydride and the formation of the corresponding amide, which is not effective as a builder. The composition is then cooled to about 26.7"C by the time the Bentone 14 clay is added.

The DTA/LAS ion-pair complex is made by mixing hydrogenated ditallow amine (available from Sherex Chemical Corp., Dublin, OH as Adogen R240, which has been topped to reduce the monotallow amine content from about 5% to less than about 1% by weight, e.g., 0.9%, to improve particle integrity and physical stability) with C114 linear alkylbenzene sulfonic acid, in a weight ratio of 90:10DTA:LAS, at 71.1-76.7"C to form a smooth syrupy liquid. The complex, at a temperature of 65.6-76.7"C, is slowly added to the 26.7"C composition under high shear mixing conditions.This causes the complex to disperse into fine droplets that freeze as particles having an average size of about 40-50 microns, and a median size of about 20 microns, as measured using a Malvern R2600 particle size analyzer. Moreover, about 69% of the particles have a size between 9 and 160 microns.

The base product is a stable isotropic liquid at 20"C and has an initial pH of about 8.2 at a concentration of 10% by weight in water at 20"C. The finished product is a stable homogeneous dispersion at 20"C and has an initial pH of about 8.6 at a concentration of 10% by weight in water at 20"C.

Other compositions of the present invention are obtained when the above molar ratio of potassium to sodium is adjusted to about 2.85; when the levels of C12 alkenyl succinic anhydride and citric acid are adjusted to 14% and 2%, respectively; and when the levels of C12 ,3 alchol polyethoxylate and 1,2-propanediol are adjusted to 5% and 18.5%, respectively.

Other compositions of the present invention are obtained when the above DTA/LAS ion-pair complex is replaced, in whole or in part, with an equivalent amount of ditallow amine (hydrogenated or unhydrogenated) complexed with C6, C8, C,O or C13 linear alkylbenzene sulfonic acid.

Claims (20)

1. A heavy-duty liquid detergent composition comprising, by weight: (a) from about 10% to about 30%, on an acid basis, of a sulfonate surfactant containing a C,O-C,6 alkyl or alkenyl group; (b) from about 1% to about 15% of an ethoxylated nonionic surfactant of the formula R'(OC2H4)nOH, wherein R' is a C,O-C,6 alkyl group of a C8-C,2 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 7% to about 20%, on an acid basis, of a C,2-C14 alkyl or alkenyl succinate builder material, (d) from about 1% to about 7%, on an acid basis, of a citrate builder material;; (e) from about 0 to about 0.04 moles per 100 grams of composition of an alkanolamine selected from the group consisting of monoethanolamine, diethanolamine and triethanolamine; (f) potassium and sodium ions in a molar ratio of potassium to sodium of from about 1.4 to about 5.0; (g) from about 5% to about 20% of propylene glycol; and (h) from about 15% to about 45% water; said composition containing from about 15% to about 40% of (a) and (b); from about 10% to about 25% of (c) and (d); from about 30% to about 55% of (a), (b), (c) and (d); and from about 30% to about 55% of (9) and (h); the weight ratio of (a) to (b) being from about 1 to about 10%; and all of said components being selected to provide an isotropic liquid at (20"C) having an initial pH of from about 6.0 to about 10.0 at a concentration of 10% by weight in water at 20"C.

2. The composition of Claim 1 wherein the sulfonate surfactant is a C11-C13 linear alkylbenzene sulfonate, and in the ethoxylated nonionic surfactant, R is a C12-C,4 alkyl group and n averages from about 3 to about 7.

3. The composition of Claim 2 comprising from about 15% to about 25%, on an acid basis, of the sulfonate surfactant, and from about 5% to about 12% of the ethoxylated nonionic surfactant.

4. The composition of Claim 3 comprising from about 10% to about 15%, on an acid basis, of the succinate builder, and from about 2% to about 5.5%, on an acid basis, of the citrate builder.

5. The composition of Claim 4 wherein the molar ratio of potassium to sodium is from about 1.5 to about 2.5.

6. The composition of Claim 5 comprising from about 8% to about 18% of 1,2-propanediol.

7. The composition of Claim 6 having a pH of from about 7 to about 9.0 at a concentration of 10% by weight in water at 20"C.

8. The composition of Claim 1 wherein the succinate builder material is added to the composition in its anhydride form.

9. The composition of Claim 8 wherein the anhydride is substantially hydrolyzed and neutralized prior to the addition of the alkanolamine.

10. The composition of Claim 1 further comprising from about 0.1% to about 10% of waterinsoluble particles having an average diameter of from about 10 to about 300 microns, said particles comprising an alkyl amine-anionic surfactant ion-pair complex having the formula:

wherein R1 and R2 can independently be C,6 to C20 alkyl or alkenyl groups, and A is an anionic surfactant selected from the group consisting of alkyl sulfonates, aryl sulfonates, alkylaryl sulfonates and paraffin sulfonates, and mixtures of such ion-pair complexes.

11. The composition of Claim 10 wherein the particles have an average diameter of from about 10 to about 1 50 microns.

12. The composition of Claim 10 wherein the particles comprise an ion-pair complex of hydrogenated ditallow amine and C6-C,3 linear alkylbenzene sulfonate,

13. The composition of Claim 10 further comprising from about 0.5% to about 1.5% of a quaternized montmorillonite clay.

14. The composition of Claim 10 being substantially free of alkyl sulfate and alkyl ethoxy sulfate surfactants pf the formula RO(C2H40),,SO3M, where R is a ClO-Cl6 alkyl or hydroxyalkyl group, m is O or averages up to about 4, and M is a compatible cation.

15. The composition of Claim 10 being substantially free of ethanol.

16. The composition of Claim 9 further comprising from about 0.5% to about 8% of waterinsoluble particles having an average diameter of from about 10 to about 300 microns, said particles comprising an alkyl amine-anionic surfactant ion-pair complex having the formula:

wherein R1 and R2 can independently be C,6 to C20 alkyl or alkenyl groups, and A is an anionic surfactant selected from the group consisting of alkyl sulfonates, aryl sulfonates, alkylaryl sulfonates and paraffin sulfonates, and mixtures of such ion-pair complexes.

17. The composition of Claim 16 wherein the particles have an average diameter of from about 10 to about 150 microns and comprise an ion-pair complex of hydrogenated ditallow amine and C6-C,3 linear alkylbenzene sulfonate.

18. The composition of Claim 17 comprising an ion-pair complex of hydrogenated ditallow amine and Car,4 linear alkylbenzene sulfonate.

19. The composition of Claim 17 further comprising from about 0.5% to about 1.5% of a quarternized montmorillonite clay.

20. The composition of Claim 17 wherein the ditallow amine contains less than about 1% -monotallow amine.

DEH:fp(1 12-C39)