DE69113259T2 - Polyhydroxy fatty acid amide surfactants and a softening system based on clay-containing detergent compositions. - Google Patents

Description

Field of the invention

The present invention relates to softening by means of a clay softening system containing laundry compositions.

Background of the invention

Clays, particularly smectic clays, are known fabric softeners and their use in fabric softening has been described in the prior art. Representative of the prior art is GB-B-1 400 898. However, it is equally well recognized that the deposition of these clays is far from complete; in fact, under typical European washing conditions, less than half of the available clay is deposited on the fabric, the remainder being washed away with the wash liquor during subsequent rinsing steps.

It was found that one reason for the incomplete deposition was the negative interaction between the clay and conventional non-ionic surfactants when used in significant proportions (i.e. above 4%).

Until now, it was therefore necessary to limit the proportion of non-ionic surfactants in clay-containing softening detergent compositions in order to achieve good softening performance of the clay or to add a clay flocculant as described in EP-A-299 575.

It has now been found that certain polyhydroxy fatty acid amides, which act as non-ionic surfactants, are more compatible with fabric softening clays.

This finding allows the formulation of softener detergent compositions which exhibit better cleaning performance due to the now acceptable higher levels of non-ionic surfactant and better softening performance due to the increased deposition of clay, without the absolute necessity of adding clay flocculants.

State of the art regarding polyhydroxy fatty acid amides

A variety of polyhydroxy fatty acid amides have been described in the prior art. US Patent 2,965,576 and GB Patent 809,060 relate to detergent compositions containing anionic surfactants and certain amide surfactants, which may include N-methylglucamide, as low temperature foam boosters.

US Patent 2,703,798 relates to aqueous detergent compositions containing the condensation reaction product of N-alkylglucamine and an aliphatic ester of a fatty acid. The product of this reaction is said to be usable in aqueous detergent compositions without further purification.

PCT International Application WO 83/04412 relates to amphiphilic compounds containing aliphatic polyhydroxyl groups which are said to be useful for a variety of purposes, including use as surfactants in cosmetics, medicines, shampoo, lotions and eye ointments.

US Patent 2,982,737 relates to detergent bars containing urea, anionic sodium lauryl sulfate surfactant and a nonionic N-alkylglucamide surfactant selected from N-methyl-N-sorbityl lauramide and N-methyl-N-sorbityl myristamide.

Other glucamide surfactants are described, for example, in DT 2 226 872, which relates to detergent compositions containing one or more surfactants and image salts selected from polymeric phosphates, sequestering agents and washing alkali.

GB Patent 745 036 relates to heterocyclic amides and carboxylic acid esters thereof, which are said to be usable as chemical intermediates, emulsifiers, wetting and dispersing agents, detergents, textile softeners, etc.

Summary of the connection

The present invention relates to detergent compositions comprising:

(a) at least 1% by weight of polyhydroxy fatty acid amide surfactant of the formula:

(I) R²- - -Z

wherein R¹ is H, C₁-C₄ hydrocarbon, 2-hydroxyethyl, 2-hydroxypropyl or a mixture thereof, R² is C₅-C₃₁ hydrocarbon and

Z is a polyhydroxyhydrocarbon having a linear hydrocarbon chain with at least three hydroxyl groups directly attached to the chain or alkoxylated derivatives thereof;

(b) a clay plasticizer system.

Detailed description of the invention Polyhydroxy fatty acid amide surfactant

The compositions described herein contain at least 1%, typically 3 to 50%, preferably 3 to 30% of the polyhydroxy fatty acid amide surfactant described below.

The polyhydroxy fatty acid amide surfactant component of the present invention comprises compounds of the structural formula:

(1) R²- - -Z

wherein R¹ is H, C₁-C₄ hydrocarbon, 2-hydroxyethyl, 2-hydroxypropyl or a mixture thereof, preferably C₁-C₄ alkyl, more preferably C₁ or C₂ alkyl, most preferably C₁ alkyl (ie methyl); and R² is a C₅-C₃₁ hydrocarbon, preferably a straight chain C₇-C₁₇ alkyl or alkenyl, more preferably a straight chain C₇-C₁₇ alkyl or alkenyl, most preferably a straight chain C₁₁-C₁₇ alkyl or alkenyl, or a mixture thereof; and Z is a polyhydroxy hydrocarbon having a linear hydrocarbon chain with at least 3 hydroxy groups directly linked to the chain, or an alkoxylated derivative thereof (which is preferably ethoxylated or propoxylated). Z is preferably derived from a reducing sugar in a reductive amination reaction; more preferably Z is glycityl. Suitable reducing sugars include glucose, fructose, maltose, lactose, galactose, mannose and xylose. High dextrose corn syrup, high fructose corn syrup and high maltose corn syrup as well as the individual sugars listed above can be used as raw materials. It is to be understood that these corn syrups can give a mixture of sugar components for Z. Z is preferably selected from the group consisting of -CH₂-(CHOH)n-CH₂OH, CH(CH₂OH)-(CHOH)n-1-CH₂OH, -CH₂-(CHOH)₂(CHOR')(CHOH)CH₂OH and alkoxylated derivatives thereof, wherein n is an integer from 3 to 5 (inclusive) and R' is H or a cyclic or aliphatic monosaccharide. Most preferred are glycityls in which n is 4, especially -CH₂-(CHOH)₄-CH₂OH

In formula (I), R¹ may be, for example, N-methyl, N-ethyl, N-propyl, N-isopropyl, N-butyl, N-2-hydroxyethyl or N-2-hydroxypropyl.

R²-CO-N< can be e.g. cocamide, stearamide, oleamide, lauramide, myristamide, capricamide, palmitamide, tallowamide etc.

Z can be 1-deoxyglucityl, 2-deoxyfructityl, 1-deoxymaltityl, 1-deoxylactityl, 1- deoxygalactityl, 1-deoxymannityl, 1-deoxymaltotriotityl, etc.

Processes for preparing polyhydroxy fatty acid amides are known to those skilled in the art. In general, they can be prepared by reacting an alkylamine with a reducing sugar in a reductive amination reaction to form the corresponding N-alkyl polyhydroxyamine and then reacting the N-alkyl polyhydroxyamine with an aliphatic fatty ester or triglyceride in a condensation/amidation step to form the N-alkyl N-polyhydroxy fatty acid amide product. Processes for preparing compositions containing polyhydroxy fatty acid amides are described, for example, in GB Patent Specification 809,060, US Patent 2,965,576, US Patent 2,703,798 and US Patent 1,985,424.

In a preferred process for preparing N-alkyl or N-hydroxyalkyl-N- deoxyglycityl fatty acid amides wherein the glycityl moiety is derived from glucose and the N-alkyl or N-hydroxyalkyl functionality is N-methyl, N-ethyl, N-propyl, N-butyl, N-hydroxyethyl or N-hydroxypropyl, the product is prepared by reacting N-alkyl or N-hydroxyalkyl glucamine with a fatty acid ester selected from fatty methyl esters, fatty ethyl esters and fatty triglycerides in the presence of a catalyst selected from the group consisting of trilithium phosphate, trisodium phosphate, tripotassium phosphate, tetrasodium pyrophosphate, pentapostic tripolyphosphate, lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, disodium tartrate, dipotassium tartrate, sodium potassium tartrate, trisodium citrate, tripotassium citrate, basic sodium silicates, basic potassium silicates, basic sodium aluminosilicates and basic potassium aluminosilicates and mixtures thereof. The amount of catalyst is preferably between 0.5 mole % and 50 mole %, more preferably between 2.0 mole % and 10 mole %, on an N-alkyl or N-hydroxyalkyl glucamine mole basis. The reaction is preferably carried out at 138°C to 170°C for typically 20 to 90 minutes. When the triglycerides are used as a fatty ester source in the reaction mixture, the reaction is also preferably carried out using 1 to 10 weight % of a phase transfer agent, calculated on a weight basis of the total reaction mixture, selected from saturated fatty alcohol polyethoxylates, alkyl polyglycosides, linear glycamide surfactants and mixtures thereof.

Preferably, the method is carried out as follows:

(a) preheating the fatty ester to about 138ºC to about 170ºC;

(b) adding the N-alkyl or N-hydroxyalkyl glucamine to the heated fatty acid ester and mixing to the extent necessary to produce a two-phase liquid/liquid mixture;

(c) mixing the catalyst into the reaction mixture; and

(d) Stir for the indicated reaction time.

Also preferred is the addition of 2% to 20% of preformed linear N-alkyl/N-hydroxyalkyl-N-linear glucosyl fatty acid amide product to the reaction mixture, based on the weight of reactants, as the phase transfer agent when the fatty ester is a triglyceride. This fertilizes the reaction, thereby increasing the reaction rate.

The polyhydroxy "fatty acid" amide materials used herein also offer the detergent manufacturer the advantages of being made entirely or primarily from natural, renewable, non-petrochemical feedstocks and being degradable. They also exhibit low toxicity to aquatic life.

It should be noted that the process for preparing polyhydroxy fatty acid amides of formula (I) not only produces these, but also typically produces certain amounts of non-volatile by-products such as ester amides and cyclic polyhydroxy fatty acid amide. The amounts of these by-products will vary depending on the particular reactants and the process conditions. Preferably, the polyhydroxy fatty acid amide incorporated into the detergent compositions herein is presented in such a form that the polyhydroxy fatty acid amide-containing composition added to the detergent contains less than 10%, preferably less than 4%, cyclic polyhydroxy fatty acid amide. The preferred processes described above are advantageous in that they produce fairly low amounts of by-products, including such cyclic amide by-products.

The clay softening system

The clay softening system includes a fabric softening clay and, although not essential, may additionally include a clay flocculant and/or a humectant.

The fabric softener clay

The clay softener system described herein includes a fabric softening clay present in an amount of at least 0.5%, preferably 4% to 30%, by weight of the detergent composition. The preferred clays are of the smectic type.

The smectic type clays are widely used as fabric softening ingredients in detergent compositions. Most of these clays have a cation exchange capacity of at least 50 meq./100g.

Smectic clays can be described as expandable three-layer materials consisting of aluminosilicates or magnesium silicates.

There are two distinct classes of smectic type clays; the first has alumina present in the silicate crystal lattice, the second class of smectites has magnesium oxide present in the silicate crystal lattice.

The general formulas of these smectites are Al₂(Si₂O₅)₂(OH)₂ and Mg₃(Si₂O₅)(OH)₂ for the alumina type and for the magnesia type, respectively. The proportion of water of hydration can vary with the processing the clay has undergone. Furthermore, atomic substitution by iron and magnesium can occur within the crystal lattice of the smectites, whereas metal cations such as Na⁺, Ca²⁺ and H⁺ can co-exist in the water of hydration to ensure electrical neutrality.

It is common to distinguish between clays on the basis of the cation that is predominantly or exclusively absorbed. For example, a sodium clay is one in which the absorbed cation is predominantly sodium. Such absorbed cations can be involved in equilibrium exchange reactions with cations present in aqueous solutions. In such equilibrium reactions, one equivalent weight of solution cation replaces one equivalent of sodium, e.g. it is common to express the clay cation exchange capacity in terms of milliequivalents per 100g of clay (meq/100g).

The cation exchange capacity of clays can be determined by various means, including electrodialysis, by exchange with ammonium ions followed by titration, or by a methylene blue method, all of which are described in Grimshaw, The Chemistry and Physics of Clays, Interscience Publishers, Inc., pages 264-265 (1971). The cation exchange capacity of a clay mineral relates to such factors as the expandability of the clay, the charge of the clay, which in turn is determined at least in part by the lattice structure, and the like. The ion exchange capacity of clays varies widely, ranging from 2 meq/100g for kaolinites to 150 meq/100g, and beyond for certain clays of the montmorillonite type. Illite clays have an ion exchange capacity somewhere in the lower part of the range, about 26 meq/100g for an average illite clay.

It has been found that illite and kaolinite clays, with their relatively low ion exchange capacities, are not useful in the present compositions. In fact, such illite and kaolinite clays constitute a major component of clay impurities. However, smectites such as nontronite, with an ion exchange capacity of about 50 meq/100g, and saponite, which has an ion exchange capacity of more than 70 meq/100g, have been found to be useful fabric softeners.

The smectic clays commonly used for the purpose described here are all commercially available. Such clays include, for example, montmorillonite, volchonskoite, nontronite, hectorite, saponite, sauconite and vermiculite. The clays described here are available under commercial names such as "Fooler Clay" (clays found in relatively thin veins above the main bentonite or montmorillonite vein in the Black Hills) and various trade names such as Thixogel #1 (also "Thixo-Jell") and Gelwhite GP from Georgia Kaolin Co. Elizabeth, New Jersey; Volclay BC and Volclay #325 from American Colloid Co. Skokie, Illinois; Black Hills Bentonite BH 450 from International Minerals and Chemicals; and as Veegum Pro and Veegum F from R. T. Vanderbilt. It is to be recognized that such smectite-type minerals obtained under the commercial and trade names mentioned may comprise mixtures of several different mineral types. Such mixtures of smectite minerals are suitable for the use described herein.

Preferred for the use described herein are montmorillonite clays with an ion exchange capacity of 50 to 100 meq/100g, which corresponds to a layer charge of approximately 0.2 to 0.6.

Hectorites of natural origin in the form of particles of the general formula are quite suitable

[(Mg3-xLix)Si4-yMeyO10(OH2-zFz)]-(x+y)/nMn+

where MeIII is Al, Fe or B; or y=o; Mn+ is a monovalent (n=1) or divalent (n=2) metal ion selected e.g. from Na, Mg, Ca, Sr.

In the formula above, the value (x+y) is the layer charge of the hectorite clay.

Such hectorite clays are preferably selected on the basis of their layer charge properties, i.e. at least 50% in the range of 0.23 to 0.31.

More suitable are hectorite clays of natural origin with a layer charge distribution such that at least 65% lies in the range of 0.23 to 0.31.

The Hectorite clays suitable for the present composition should preferably be soda clays for better plasticizing activity.

Sodium clays either occur naturally or are naturally occurring calcium clays which have been treated to convert them to sodium clays. When calcium clays are used in the present compositions, a sodium salt can be added to the compositions to convert the calcium clay to a sodium clay. Preferably, such a salt is sodium carbonate, which is typically added in an amount of up to 5% of the total amount of the clay.

Examples of hectorite clays suitable for the present compositions include Bentone EW and Macaloid from NL Chemicals, N.J. USA, and hectorite from Industrial Mineral Ventures.

Clay flocculants

The compositions described herein may contain from 0.05 to 20% by weight of the clay of flocculant when its molecular weight is from 150,000 to 800,000, and from 0.005 to 2% by weight of the clay when its molecular weight is from 800,000 to 5 million. Most of these materials are fairly long chain polymers and copolymers derived from such monomers as ethylene oxide, acrylamide, acrylic acid, dimethylaminoethyl methacrylate, vinyl alcohol, vinyl pyrrolidone, ethyleneimine. Gums such as guar gum are also suitable.

Preferred are polymers of ethylene oxide, acrylamide or acrylic acid. For suitable interaction with the clay particles, the polymers should be fairly long chain, i.e. they should have a weight average molecular weight of at least 100,000. For sufficient water solubility, the weight average molecular weight of the polymer should not exceed 10 million. Most preferred are polymers with a weight average molecular weight of 150,000 to 5 million.

The humectant

The organic humectant optionally employed in the clay agglomerates described herein may be any of the various water-soluble materials used for such a purpose. The organic humectant is preferably selected from the group consisting of a) aliphatic hydrocarbon polyols having 2 to 9 carbon atoms, b) ether alcohols derived from the polyols of a), c) ester alcohols derived from the polyols of a), d) mono- and oligosaccharides, and mixtures thereof.

Highly preferred humectants include glycerin, ethylene glycol, propylene glycol, and the dimers and trimers of glycerin, ethylene glycol, and propylene glycol.

The clay plasticizer system may contain 0.5% to 30%, preferably 2% to 15% of the humectant, based on the weight of the clay.

Detergent surfactant system

In addition to the polyhydroxy fatty acid amide described herein, the present compositions may contain one or more additional surfactants, which may be anionic, cationic or nonionic. Typically, the surfactant system will include one or more anionic and/or nonionic surfactants in addition to the polyhydroxy fatty acid amide. It is particularly preferred to include an anionic surfactant for effective overall cleaning under a wide variety of wash conditions. In particular, the benefits of this invention are particularly realized when the compositions described herein include hardness sensitive surfactants such as alkyl sulfate, alkyl ester sulfonates (e.g., methyl ester sulfonates), alkyl alkoxylated sulfonates (e.g., alkyl ethoxylated sulfonates), and alkylbenzene sulfonates (e.g., linear alkylbenzene sulfonate). The further incorporation of a conventional nonionic surfactant such as an alkyl ethoxylate or an alkyl polyglycoside as described below is desirable. However, the levels of such conventional nonionic surfactants in clay-containing detergent compositions must be limited in view of negative interaction with the clay. (Accordingly, conventional nonionic surfactants should not be present at a level exceeding 4% by weight of the detergent composition.) Typically, the amount of additional surfactant present is from 1 to 50% by weight of the detergent composition, preferably from 3 to 40%, more preferably from 5 to 30%.

Suitable anionic surfactants include alkyl ester sulfonate surfactants having the following structural formula:

in which R³ is a C₈-C₂₀ hydrocarbon radical, preferably an alkyl or a combination thereof, R⁴ is a C₁-C₆ hydrocarbon radical, preferably an alkyl or a combination thereof, and M is a cation which forms a water-soluble salt with the alkyl ester sulfonate. Suitable salts include metal salts such as sodium, potassium and lithium salts, and substituted or unsubstituted ammonium salts such as methyl, dimethyl, trimethyl and quaternary ammonium cations, e.g. tetramethylammonium and dimethylpiperidinium, and cations derived from alkanolamines, e.g. monoethanolamine, diethanolamine and triethanolamine. Preferably R³ is C₁₀-C₁₆alkyl and R⁴ is methyl, ethyl or isopropyl. Particularly preferred are the methyl ester sulfonates wherein R³ is C₁₄-C₁₆alkyl.

Alkyl sulfate surfactants of the formula ROSO₃M, wherein R is preferably a C₁₀₋₄-C₂₄-hydrocarbon, preferably an alkyl or hydroxyalkyl having a C₁₀₋₄-C₂₀-alkyl moiety, more preferably a C₁₂₋₄-C₁₈-alkyl or hydroxyalkyl and M is H or a cation, e.g. an alkyl metal cation (e.g. sodium, potassium, lithium), substituted or unsubstituted ammonium cations such as methyl, dimethyl and trimethylammonium cations and quaternary ammonium cations, e.g. tetramethylammonium and dimethylpiperidinium, and cations derived from alkanolamines such as ethanolamine, diethanolamine, triethanolamine, and mixtures thereof, and the like. Typically, alkyl chains having C₁₂-C₁₆ alkyl chains are preferred for lower wash temperatures (e.g. below 50°C) and C₁₆-C₁₈ alkyl chains for higher wash temperatures (e.g. above 50°C).

Alkyl-alkoxylated sulfate surfactants of the formula RO(A)mSO₃M, wherein R is an unsubstituted C₁₀₋₄-C₂₄-alkyl or -hydroxyalkyl group having a C₁₀₋₄-C₂₄-alkyl moiety, preferably a C₁₂₋₄-C₂₀-alkyl or -hydroxyalkyl, more preferably a C₁₂₋₄-C₁₈-alkyl or -hydroxyalkyl, A is an ethoxy or propoxy moiety, m is above zero, typically between 0.5 and 6, more preferably between 0.5 and 3, and M is H or a cation, which is e.g. a metal cation (e.g. sodium, potassium, lithium, calcium, magnesium, etc.),

Ammonium or an ammonium substituted cation. Alkyl ethoxylated sulfates as well as alkyl propoxylated sulfates are contemplated herein. Specific examples of substituted ammonium cations include methyl, dimethyl, trimethylammonium and quaternary ammonium cations such as tetramethylammonium, dimethylpiperidinium, and cations derived from alkanolamines, e.g. monoethanolamine, diethanolamine and triethanolamine, and mixtures thereof. Exemplary surfactants are C₁₂-C₁₈alkyl polyethoxylate (1,0) sulfate, C₁₂-C₁₈alkyl polyethoxylate (2,25) sulfate, C₁₂-C₁₈alkyl polyethoxylate (3,0) sulfate and C₁₂-C₁₈alkyl polyethoxylate (4,0) sulfate, wherein M is conveniently selected from sodium and potassium.

These salts (including, for example, sodium, potassium, ammonium and substituted ammonium salts such as mono-, di- and triethanolamine salts) of soap, linear C9-C20 alkylbenzenesulfonates, primary or secondary C8-C22 alkanesulfonates, C8-C24 olefinsulfonates, sulfonated polycarboxylic acids prepared by the sulfonation of the pyrolysis product of alkaline earth metal citrates, such as described in British Patent Specification No. 1 082 179, alkylglycerolsulfonates, fatty acid acylglycerolsulfonates, fatty acid oleylglycerol sulfates, alkylphenolethylene oxide ether sulfates, paraffinsulfonates, alkylphosphates, isethionates such as N-acylisethionates, Acyl taurates, fatty acid amides of methyl tau and alkyl succinamates and - sulfosuccinates, monoesters of sulfosuccinate, diesters of sulfosuccinate (especially saturated or unsaturated C6-C14 diesters), N-acyl sarcosinates, sulfates of alkyl polysaccharides such as the sulfates of alkyl polyglucoside (the non-ionic, non-sulfated compounds are described below), branched primary alkyl sulfates, alkyl polyethoxycarboxylates such as those of the formula RO(CH2CH2O)k-CH2COO-M+, where R is a C8-C22 alkyl, k is an integer from 0 to 10 and M is a soluble salt-forming cation, and fatty acids esterified with isethionic acid and neutralized with sodium hydroxide. Resin acids and hydrogenated resin acids are also suitable, such as rosin, hydrogenated rosin and resin acids and hydrogenated resin acids present in or derived from tall oil. Other examples are described in "Surface Active Agents and Detergents" (Volumes I and II by Schwartz, Perry and Berch). A variety of such surfactants are also generally described in U.S. Patent 3,929,678.

Suitable conventional nonionic detergent surfactants are generally described in U.S. Patent 3,939,678. Exemplary non-limiting classes of useful nonionic surfactants are:

Polyethylene oxide, polypropylene oxide and polybutylene oxide condensates of alkylphenols. In general, the polyethylene oxide condensates are preferred. Commercially available nonionic surfactants of this type include Igepal™CO-630, marketed by GAF Corporation, and Triton™X-45, X-114, X-100 and X-102, all marketed by Rohm & Haas Company. These surfactants are commonly referred to as alkylphenol alkoxylates, e.g., alkylphenol ethoxylates.

The condensation products of C12-C22 aliphatic alcohols with 1 to 25 moles of ethylene oxide. Examples of commercially available nonionic surfactants of this type include Tergitol™ 15-S-9 (the condensation product of C11-C15 secondary linear alcohol with 9 moles of ethylene oxide), Tergitol™ 24-L-6NMW (the condensation product of C12-C14 primary alcohol with 6 moles of ethylene oxide having a narrow molecular weight distribution), both marketed by Union Carbide Corporation; NEODOL™ 45-9 (the condensation product of linear C₁₄-C₁₅ alcohol with 9 moles of ethylene oxide), Neodol™ 23-6.5 (the condensation product of linear C₁₂-C₁₃ alcohol with 6.5 moles of ethylene oxide), Neodol™ 45-7 (the condensation product of linear C₁₄-C₁₅ alcohol with 7 moles of ethylene oxide), Neodol™ 45-4 (the condensation product of linear C₁₄-C₁₅ alcohol with 4 moles of ethylene oxide), marketed by Shell Chemical Company, and KYro™ EOB (the condensation product of C₁₃-C₁₅ alcohol with 9 moles of ethylene oxide), marketed by The Procter & Gamble Company. These are commonly referred to as alkyl ethoxylates.

The condensation products of ethylene oxide with a hydrophobic base formed by the condensation of propylene oxide with propylene glycol. Examples of compounds of this type include certain commercially available Pluronic™ surfactants, marketed by BASF.

The condensation products of ethylene oxide with the product resulting from the reaction of propylene oxide and ethylenediamine. Examples of this type of nonionic surfactant include certain commercially available Tetronic™ compounds marketed by BASF.

Amine oxides with the following formula:

wherein R³ is an alkyl, hydroxyalkyl or alkylphenyl group or a mixture thereof having 8 to 22 carbon atoms; R⁴ is an alkylene or hydroxyalkylene group having 2 to 3 carbon atoms or a mixture thereof; x is 0 to 3; and each R⁵ is an alkyl or hydroxyalkyl group having 1 to 3 carbon atoms or a polyethylene oxide group having 1 to 3 ethylene oxide groups. The R⁵ groups may be linked to one another, e.g. through an oxygen or nitrogen atom, thereby forming a ring structure.

Preferred are C₁₀-C₁₈-alkyldimethylamine oxides and C₈-C₁ 2-alkoxyethyldihydroxyethylamine oxides.

Alkyl polysaccharides described in U.S. Patent 4,656,647, Llenado, issued January 21, 1986.

The preferred alkyl polyglycosides have the formula

R²O(CnH2nO)t(glycosyl)x

wherein R² is selected from the group consisting of alkyl, alkylphenyl, hydroxyalkyl, hydroxyalkylphenyl and mixtures thereof, in which the alkyl groups contain from 10 to 18, preferably 12 to 14, carbon atoms; n is 2 or 3, preferably 2; t is 0 to 10, preferably 0; and x is from 1.3 to 10, preferably from 1.3 to 3, most preferably from 1.3 to 2.7. The glycosyl is preferably derived from glucose. To prepare these compounds, the alcohol or alkylpolyethoxy alcohol is first formed and then reacted with glucose or a glucose source to form the glucoside (linker at the 1-position). The additional glycosyl units can then be linked between their 1-position and the 2-, 3-, 4- and/or 6-position of the previous glycosyl units, preferably at the 2-position.

Cationic detergent surfactants may also be included in the detergent compositions of the present invention. Cationic surfactants include ammonium surfactants such as alkyldimethylammonium halides and those surfactants of the formula:

[R₂(OR³)y][R⁴(OR³)y]₂R⁵N⁺X⁻

wherein R2 is an alkyl or alkylbenzyl group having from about 8 to about 18 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, ring structures formed by joining the two R4 groups, -CH2CHOH-CHOHCOR6CHOHCH2OH, wherein R6 is is any hexose or any hexose polymer having a molecular weight of less than 1000, and hydrogen when y is not 0; R⁵ is the same as R⁴ or an alkyl chain wherein the total number of carbon atoms of R² plus R⁵ is not more than about 8; each y is 0 to 10, and the sum of the y values is between 0 and 15; and x is any compatible anion.

Other cationic surfactants useful herein are also described in U.S. Patent 4,228,044, Cambre.

Other surfactants

Ampholytic surfactants can be incorporated into the detergent compositions herein. These surfactants can be broadly described as aliphatic derivatives of secondary or tertiary amines or as aliphatic derivatives of heterocyclic, secondary and tertiary amines in which the aliphatic moiety can be straight or branched chain. One of the aliphatic substituents contains at least 8 carbon atoms, typically 8 to 18 carbon atoms, and at least one contains an anionic, water-solubilizing group, e.g., carboxy, sulfonate, sulfate. See U.S. Patent No. 3,929,678 for examples of ampholytic surfactants.

Zwitterionic surfactants can also be incorporated into the detergent compositions herein. These surfactants can be broadly described as derivatives of secondary and tertiary amines, derivatives of heterocyclic, secondary and tertiary amines, or derivatives of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. See U.S. Patent No. 3,929,678 for examples of zwitterionic surfactants.

Ampholytic and zwitterionic surfactants are generally used in combination with one or more anionic and/or non-ionic surfactants.

Form of composition and conditions of application

The compositions of the present invention may be in either particulate form or in the form of an aqueous dispersion of the clay particles, depending on the required conditions of use. Regardless of the form, the composition of the invention may be added during the main wash cycle or during the rinse phase of the washing process.

The particular shape includes both "regular" and high-density, "compact" versions.

Detergent builder

Detergent compositions of the present invention may include inorganic as well as organic detergency builders to help control mineral hardness.

The amount of builder can vary widely depending on the final application of the composition and its desired physical form. Liquid formulations contain at least 1%, more typically 5 to 50%, preferably 5 to 30% by weight, of detergent builder.

Granular formulations typically contain at least 1% by weight, more typically 10 to 80% by weight, preferably 15 to 50% by weight, of the wax builder. However, lower or higher builder levels should not be excluded.

Inorganic detergent builders include, but are not limited to, alkali metal, ammonium and alkanolammonium salts of phosphonates, silicates, carbonates (including bicarbonates and sesquicarbonates), sulfates and aluminosilicates.

Examples of silicate builders are the alkali metal silicates, particularly those having a SiO₂:Na₂O ratio in the range of 1.6:1 to 3.2:1, and layered silicates such as the sodium layered silicates described in U.S. Patent 4,664,839. However, other silicates may also be useful, such as magnesium silicate, which can serve as a lump-forming agent in granular formulations, as a stabilizer for oxygen bleaches, and as a component for foam control systems.

Examples of carbonate builders are the alkali and alkaline earth carbonates, including sodium carbonate and sesquicarbonate and mixtures thereof with ultrafine calcium carbonate, as described in German Patent Application No. 2 321 001.

Preferred aluminosilicates are zeolite builders with the formula:

NaZ[(AlO₂)Z (SiO₂)y] xH₂O

wherein z and y are integers of at least 6, the molar ratio of z to y is in the range from 1.0 to about 0.5, and z is an integer from about 15 to about 264.

Useful aluminosilicate ion exchange materials are commercially available. These aluminosilicates may be crystalline or armorphous in structure and may be naturally occurring aluminosilicates or synthetically derived. A process for preparing aluminosilicate exchange materials is described in U.S. Patent 3,985,669. In a particularly preferred embodiment, the crystalline aluminosilicate ion exchange material has the formula:

Na₁₂[(AlO₂)₁₂(SiO₂)₁₂] xH₂O

where x is 20 to 30, especially about 27. This material is known as zeolite A. Preferably, the aluminosilicate has a particle size of about 0.1 to 10 µm in diameter.

Examples of phosphonate builder salts are the water-soluble salts of ethane-1-hydroxy-1,1-diphosphonate, especially the sodium and potassium salts, the water-soluble salts of methylenediphosphonic acid, e.g. the trisodium and tripotassium salts, and the water-soluble salts of substituted methylenediphosphonic acids, such as trisodium and tripotassium methylidene, isopropylidene, benzylmethylidene and halomethylidene phosphonates. Phosphonate builder salts of the types mentioned above are described in U.S. Patent Nos. 3,159,581 and 3,213,030, U.S. Patent No. 3,422,021, and U.S. Patent Nos. 3,400,148 and 3,422,137.

Organic detergency builders suitable for the purposes of the present invention include, but are not limited to, a variety of polycarboxylate compounds. As used herein, "polycarboxylate" refers to compounds having a plurality of carboxylate groups, preferably at least 3 carboxylates.

Polycarboxylate builders can generally be added to the composition in acid form, but they can also be added in the form of a neutralized salt. When used in salt form, alkali metal such as sodium, potassium and lithium salts, especially sodium salts, or ammonium and substituted ammonium (e.g. alkanolammonium) salts are preferred.

A variety of categories of useful materials are included in the polycarboxylate builders. An important category of polycarboxylate builders includes the ether polycarboxylates. A variety of ether polycarboxylates have been described for use as detergent builders. Examples of useful ether polycarboxylates include oxydisuccinate as described in U.S. Patent 3,128,287, Berg, and U.S. Patent 3,635,830.

A specific type of polycarboxylates useful as builders in the present invention also includes those having the following general formula:

CH(A)(COOX)-CH(COOX)-O-CH(COOX)-CH(COOX)(B)

wherein A is H or OH; B is H or -O-CH(COOX)-CH2(COOX); and X is H or a salt-forming cation. For example, in the general formula above, if A and B are both H, then the compound is oxydisuccinic acid and its water-soluble salts. If A is OH and B is H, then the compound is tartrate monosuccinic acid (TMS) and its water-soluble salts. If A is H and B is -O-CH(COOX)-CH2(COOX), then the compound is tartrate disuccinic acid (TDS) and its water-soluble salts. Mixtures of these builders are particularly preferred for the use described. Particularly preferred are mixtures of TMS and TDS in a weight ratio of TMS to TDS between 97:3 to 20:80. These builders are described in US Patent 4,663,071.

Suitable ether polycarboxylates also include cyclic compounds, particularly alicyclic compounds, such as those described in U.S. Patents 3,923,679, 3,835,163, 4,158,635, 4,120,874 and 4,102,903.

Other useful detergent builders include the ether hydroxypolycarboxylates of the following structure:

HO-[C(R)(COOM)-C(R)(COOM)-O]n-H

wherein M is hydrogen or a cation in which the resulting salt is water soluble, preferably an alkali metal, ammonium or substituted ammonium cation, n is 2 to 15 (preferably n is 2 to 10, more preferably n is on average 2 to 4) and each R is the same or different and is selected from hydrogen, C1-4 alkyl or substituted C1-4 alkyl (preferably R is hydrogen).

Other ether polycarboxylates include copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1,3,5-trihydroxybenzene-2,4,6-trisulfonic acid, and carboxymethyl oxysuccinic acid.

Organic polycarboxylate builders also include the various alkali metal, ammonium and substituted ammonium salts of polyacetic acids. Examples include the sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid and nitrilotriacetic acid.

Also included are polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene-1,3,5-tricarboxylic acid and carboxymethyloxysuccinic acid and soluble salts thereof.

Citrate builders, e.g. citric acid and soluble salts thereof, are polycarboxylate builders of particular importance for liquid heavy-duty detergent formulations, but they can also be used in granular compositions. Suitable salts include the metal salts such as sodium, lithium and potassium salts, as well as ammonium and substituted ammonium salts.

Other carboxylate builders include the carboxylated carbohydrates described in U.S. Patent 3,723,322.

Also useful in the detergent compositions of the present invention are the 3,3-dicarboxy-4-oxa-1,6-hexanedioates and related compounds described in US Patent 4,566,984. Useful succinic acid builders include the C5-C20 alkyl succinic acids and salts thereof. A particularly preferred compound of this type is dodecenyl succinic acid. Alkyl succinic acids typically have the general formula R-CH(COOH)CH2(COOH); i.e., derivatives of succinic acid wherein R is hydrocarbon, e.g. C10-C20 alkyl or alkenyl, preferably C12-C16, or wherein R may be substituted with hydroxyl, sulfo, sulfoxy or sulfone substituents, all of which are described in the above-mentioned patents.

The succinate builders are preferably used in the form of their water-soluble salts, including sodium, potassium, ammonium and alkanolammonium salts.

Specific examples of succinate builders include lauryl succinate, myristyl succinate, palmityl succinate, 2-dodecenyl succinate (preferred), 2-pentadecenyl succinate, and the like. Lauryl succinates are the preferred builders of this group and are described in European patent application EP-A-0 200 263.

Examples of useful builders also include sodium and potassium carboxymethyloxymalonate, carboxymethyloxysuccinate, cis-cyclohexane hexacarboxylate, water-soluble polyacrylates (these polyacrylates having molecular weights up to over about 2000 can also be used effectively as dispersants), and the copolymers of maleic anhydride with vinyl methyl ether or ethylene.

Other suitable polycarboxylates are the polyacetal carboxylates described in U.S. Patent 4,144,226. These polyacetal carboxylates can be prepared by bringing together an ester of glyoxylic acid and a polymerization initiator under polymerization conditions. The resulting polyacetal carboxylate ester is then attached to chemically stable end groups to stabilize the polyacetal carboxylate against rapid depolymerization in alkaline solution, converted to the corresponding salt, and added to a surfactant.

Polycarboxylate builders are also described in U.S. Patent 3,308,067. Such materials include water-soluble salts of homo- and copolymers of aliphatic carboxylic acids such as maleic acid, itaconic acid, mesaconic acid, fumaric acid, aconitic acid, citraconic acid and methylenemalonic acid.

Other organic builders known in the art may also be used. For example, noncarboxylic acids and soluble salts thereof may be employed with long chain hydrocarbon residues. These would include materials generally referred to as "soaps." Chain lengths of C10-C20 are typically used. The hydrocarbon residues may be saturated or unsaturated.

Enzymes

Enzymes can be included in detergent formulations for a variety of purposes, including the removal of, for example, protein-based, carbohydrate-based or triglyceride-based stains and to prevent dye relugee transfer. The enzymes to be incorporated include proteases, amylases, lipases, cellulases and peroxidases, and mixtures thereof. They can be of any suitable origin, such as plant, animal, bacterial, fungal or yeast. Commercially available proteolytic enzymes suitable for the removal of protein-based stains include those sold under the trade names ALCALASE and SAVINASE by Novo Industries A/S (Denmark) and MAXATASE by International Synthetics, Inc. (The Netherlands).

Amylolytic proteins include, for example, RAPDASE, International Bio-Synthetics, Inc. and TERMAMYL, Novo Industries.

Cellulases applicable to the present invention include both bacterial and fungal cellulases.

Suitable lipase enzymes for detergent application include those sold under the trade name Lipolase by Novo Industries.

Commercial detergent enzymes are typically used in the present inventions at levels of 0.001% to 2% and more.

Bleaching compounds - bleaching agents and bleach activators

The detergent compositions described herein may contain bleaching agents or bleaching compositions containing bleaching agents and one or more bleach activators.

One category of bleaching agents that can be applied includes peroxyacid per se and systems capable of generating peroxyacids in situ.

Peroxyacids "per se" herein are intended to include the alkali and alkaline earth metal salts thereof. Peroxyacids and diperoxyacids are commonly used; examples are diperoxydodecanoic acid (DPDA) or peroxyphthalic acid.

Systems that are capable of releasing peracids in situ, consist of a peroxide bleach and an activator thereof.

Peroxide bleaches are those capable of forming hydrogen peroxide in aqueous solution; these compounds are well known in the art and include hydrogen peroxide, alkali metal peroxides, organic peroxide bleaches such as urea peroxide, inorganic persalt bleaches such as the alkali metal perborates, percarbonates, perphosphates, persilicates and the like.

Preferred are sodium perborate, commercially available in the form of mono- and tetrahydrates, sodium carbonate peroxyhydrate, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate.

The released hydrogen peroxide reacts with the bleach activator to form the peroxyacid bleach. Classes of bleach activators include esters, imides, imidazoles, oximes and carbonates. In both classes, preferred materials include methyl o- acetoxybenzoates; sodium p-acetoxybenzenesulfonates such as sodium 4-nonanoxyloxybenzenesulfonate; sodium 4-octanoyloxybenzenesulfonate and sodium 4-decanoyloxybenzenesulfonate, bisphenol A diacetate; tetraacetylethylenediamine, tetraacetylhexamethylenediamine; tetraacetyl methylenediamine.

Other highly preferred peroxide bleach activators described in U.S. Patents 4,483,778 and 4,539,130 are alpha-substituted alkyl or alkenyl esters such as sodium 4-(2-chlorooctanoyloxy)benzenesulfonate, sodium 4-(3,5,5-trimethylhexanoyloxy)benzenesulfonate. Suitable peroxyacids are also peroxide bleach activators as described in published European Patent Application No. 0 166 571, i.e. compounds of the general type RXAOOH and RXAL, wherein R is a hydroxy hydrocarbon group, X is a heteroatom, A is a carbonyl bridging group and L is a leaving group, especially oxybenzenesulfonate.

Detergent additives

The compositions described herein may contain other ingredients that assist in cleaning performance, including polymeric soil release agents, chelating agents, clay or earth soil removers/anti-redeposition agents.

Polymeric dispersants

Polymeric dispersants, such as acrylic/maleic acid based copolymers, can also be used as a preferred component of the dispersant/anti-redeposition agent. Such materials include the water-soluble salts of copolymers of acrylic acid and maleic acid. The average molecular weight of such copolymers in acid form is preferably in the range of 2,000 to 100,000, preferably 5,000 to 75,000, most preferably 7,000 to 65,000. The ratio of acrylate to maleate segments in such copolymers is generally in the range of 30:1 to 1:1, more preferably 10:1 to 2:1. Water-soluble salts of such acrylic/maleic acid copolymers include, for example, the alkali metal, ammonium and substituted ammonium salts. Soluble acrylate/maleate copolymers of this type are known materials which are described in European Patent Application EP-1-66915.

Another polymeric material that may be incorporated is polyethylene glycol (PEG). PEG can act as a dispersant as well as a clay soil remover/anti-redeposition agent. Typical molecular weights for these purposes are in the range of 500 to 100,000, preferably 1,000 to 50,000, more preferably 1,500 to 10,000.

Any optical brighteners or foam suppressors may be incorporated into the compositions described herein.

Liquid detergent compositions may further contain water and other solvents as carriers. Low molecular weight primary or secondary alcohols, exemplified by methanol, ethanol, propanol and isopropanol, are suitable. Monohydric alcohols are preferred for solubilizing surfactants, but polyols such as those containing 2 to 6 carbon atoms and 2 to 6 hydroxy groups (e.g., propylene glycol, ethylene glycol, glycerin and 1,2-propanediol) may also be used.

The detergent compositions described herein are preferably formulated so that during use in aqueous cleaning operations they will have a pH in the wash water of between 6.5 and 11, preferably between 7.5 and 10.5. Liquid product formulations preferably have a pH of between 7.5 and 9.5, more preferably between 7.5 and 9.0. Techniques for regulating the pH to the recommended operating level include the use of buffers, alkalis, acids, etc. and are well known to those of ordinary skill in the art.

Experimental

This procedure exemplifies a method for preparing an N-methyl-1-deoxyglucityllauramide surfactant for use as described herein. Although an experienced chemist may alter the configuration of the equipment, equipment that can be conveniently used here is a 3 liter four-necked flask equipped with a motor-driven paddle stirrer and a thermometer of sufficient length to contact the reaction medium. In the other 2 necks of the flask are introduced a nitrogen purge and a wide side arm (Caution: a wide side arm is important in case of very rapid methanol evolution) which is connected to an efficient receiver condenser and a vacuum outlet. The latter is connected to a nitrogen purge and a vacuum gauge and then to a water aspirator and a cooling trap. A 500-watt heating mantle with a variable temperature transformer (“Variac”) used to heat the reaction is placed on a “lab boy” so that it can be easily raised or lowered to further regulate the temperature of the reaction.

N-methylglucamine (195 g, 1.0 mol, Aldrich, M4700-0) and methyl laurate (Procter & Gamble CE 1270, 220.9 g, 1.0 mol) are added to a flask. The solid/liquid mixture is heated with stirring and a nitrogen purge to obtain a melt (about 25 minutes). After the melt reached a temperature of 145ºC, a catalyst (anhydrous powdered sodium carbonate, 10.5 g, 0.1 mol, J.T. Baker) was added. The nitrogen purge was turned off and the aspirator and nitrogen vent were adjusted to create a vacuum of (5 inches (5/31 atm) Hg) 16343 Pa. From now on, the reaction temperature was maintained at 150ºC by adjusting the variac and/or raising or lowering the jacket.

Within 7 minutes, methanol bubbles began to appear at the meniscus of the reaction mixture. A vigorous reaction followed soon after. Methanol was distilled off until its rate was The vacuum was increased approximately as follows (in inches Hg at minutes): 32,686 at 9806 Pa (10 at 3), 65,372 at 22,880 Pa (20 at 7), 81,715 at 32,686 Pa (25 at 10). 11 minutes after methanol evolution began, heating and stirring were discontinued, coincidental with a slight foaming. The product was cooled and solidified.

The following examples are to be considered as exemplary compositions of the present invention and are not necessarily intended to limit or otherwise restrict the scope of the invention, the scope being determined by the following claims.

Example I

Test procedure: A 3.5 kg load of clean fabrics was washed in a Miele 423 automatic drum washing machine at 60ºC. The water hardness was 2.5 mM calcium and the concentration of the composition was 0.7% in the wash liquor. Terry cloth softness swatches were line dried prior to assessment. Comparative softness assessments were made by experts using a scale of 0 to 4 Panel Scale Units (PSU). On this scale, 0 represented no difference and 4 represented the maximum difference. Softness was assessed after one and after four wash cycles. The following compositions were prepared: % by weight Component Reference I Example I Surfactant Linear alkylbenzenesulfonate Tallow alkyl sulfate Alkyltrimethylammonium chloride Fatty acid alcohol (C₁₂-C₁₅)-ethoxylate N-methyl-N-1-deoxyglucityl-C₁₂-alkylamide Images/chelating agent Zeolite A Copolymer of maleic and acrylic acid, sodium salt Bleaching agent Sodium perborate N,N,N,T-tetraacetyl-ethylenediamine Perfume Enzymes Savinase Softening system Smectite/montmorillonite clays Glycerin Polyethylene oxide Buffer Carbonate Silicate(2.0) Addition and spraying (foam suppression, miscellaneous...)

The plasticizer performance of Example 1 (containing 5% C₁₂ alkylamide base) was compared to Reference I (containing 5% ethoxylated nonionic surfactant).

A statistically significant improvement in plasticizer performance was observed for the product containing the alkyl amide base (Example 1).

Example II

Compositions containing clay flocculants were also prepared. The softening performance of the product containing 5% alkylamide (Example II) is compared with the same product containing 5% ethoxylated non-ionic surfactant (Reference II). The test conditions are identical to those of Example 1.

The softener performance was examined after one and after four wash cycles:

Once again, a statistically significantly better softening performance was found for the product containing alkylamide compared to the product with ethoxylated nonionic surfactant. Formulation examples Ingredients Composition (wt.%) Regular products Reference product Liquid product C11-12-alkyl sulfonate Tallow alcohol sulfate (Na) C14-15-alkyl sulfate (Na) α-olefin (C12-15) sulfonate (Na) Tallow alcohol ethoxylate (EO₁₁) Fatty acid alcohol (C12-15) ethoxalate (EO7) Hydrogenated tallow fatty acid C12-44-dimethyl(hydroethyl)ammonium chloride N-methyl-N-1-deoxyglycityl-C16-18-alkylamide N-Methyl-N-1-deoxyglycityl-C12-14-alkylamide Sodium tripolyphosphate Zeolite A Sodium citrate Oleic fatty acid Citric acid C14-16-alkyl succinate 1,2-propanediol Ethanol Na metaborate octahydrate Polyethylene oxide, MG: 5 MM Polyethylene oxide, MG: 0.3 MM Sodium sulfate Sodium carbonate Sodium silicate Sodium perborate N,N,N,N-Tetraacatylethylenediamine CMC Polyacrylate (MG 1000-20,000) Polyacrylate (MG 4000-5000) Maleic acid-acrylic acid copolymer Enzymes Montrnorillonite clay Hectorite clay Addition and spraying (perfumes, enzymes, savinase, buffers, foam suppressors, miscellaneous, moisture and minor components) Rest to 100

Claims (9)

1. A detergent composition comprising a polyhydroxy fatty acid amide surfactant of the formula: wherein R¹ is H, C₁-C₄ hydrocarbon, 2-hydroxyethyl, 2-hydroxypropyl or a mixture thereof, R² is C₅-C₃₁ hydrocarbon and Z is a polyhydroxy hydrocarbon having a linear hydrocarbon chain with at least 3 hydroxyl groups directly attached to the chain or alkoxylated derivatives thereof, and a clay softening system. 2. Detergent composition according to claim 1, comprising at least 1% by weight of the polyhydroxy fatty acid amide. 3. A detergent composition according to claim 1, wherein the polyhydroxy fatty acid amide surfactant has the formula (1) wherein R¹ is methyl, R² is C₁₁-C₁₇ alkyl or alkenyl and Z is a reducing sugar-derived glycityl or an alkoxylated derivative thereof. 4. A detergent composition according to claim 1, wherein the clay-softener system comprises a clay in an amount of at least 0.5% by weight of the detergent composition. 5. A detergent composition according to claim 4, wherein the clay is a smectite-type clay. 6. A detergent composition according to claim 1, wherein the clay softener system comprises a clay flocculant. 7 A detergent composition according to claim 1, wherein the clay softener system comprises a humectant. 8. Detergent composition according to claim 1, further comprising one or more auxiliary surfactants selected from the group consisting of anionic, cationic and nonionic detergent surfactants and mixtures thereof. 9. A detergent composition according to claim 8, wherein the nonionic surfactants are present in amounts of less than 4% by weight of the detergent composition.