US3354091A - Homogeneous heavy-duty liquid detergent - Google Patents

Description

United States Patent 5 Claims. (Cl. 252-4137 This is a continuation of copending application Ser. No. 861,191 filed Dec. 22, 1959 and now abandoned, said copending application having been filed as a continuationin-part of application Serial No. 532,733, filed Sept. 6, 1955, now US. Patent No. 2,920,045, issued Jan. 5, 1960.

The present invention relates to a substantially homogeneous heavy-duty liquid detergent composition comprising a water-soluble organic detergent, a water-soluble alkaline inorganic polyphosphate salt, a water-soluble carboxyalkylcellulose salt and a water-insoluble wax, as hereinafter described and claimed.

Various types of liquid compositions in the form of lotions and liquid emulsions are known in the cosmetic art, including shampoo products. Such compositions comprise generally a suitable detergent and an opacifier, stabilizing agent or suitable waxy material in an aqueous solvent. Where soap is the detergent in a shampoo, it has been suggested to incorporate a very small amount of a water-softener such as various phosphate compounds in order to prevent formation of insoluble soaps during use of the product in hard water.

In the detergent art, however, it has been common practice to prepare detergent compositions in powdered form, as obtained by spray-drying a slurry of the detergent composition for example. In these powdered products, alkaline builder salts such as sodium tripolyphosphate and pyrophosphate have been incorporated in significant amounts to improve the detergency or Washing power for the laundering of soiled textile materials. Other salts such as sodium silicate, carbonate, carboxymethylcellulose and the like have been employed also in the preparation of powdered heavy-duty detergent compositions.

The incorporation of sodium carboxymethylcellulose or the like in a heavy-duty liquid detergent solution comprising substantial amounts of an organic detergent, such as an alkyl benzene sulfonate, and water-soluble inorganic polyphosphate salts results in a tendency towards phase separation, or formation of a plurality of distinct layers, one of which has the carboxymethylcellulose concentrated therein.

In accordance with the present invention, it has been found that the separation of the carboxymethylcellulose or the like in such liquids may be substantially prevented or inhibited by the simultaneous presence of a suitable water-insoluble wax such as hydrogenated caster oil in dispersion in the liquid.

More particularly, the present invention relates to a substantially homogeneous, pourable, heavy-duty aqueous liquid which consists essentially of alkali metal anionic sul-fonated detergent in an amount from about 5 to 30% by weight, a potassium polyphosphate salt in an amount from about -30% by weight and normally soluble in the amount of water present, and a lower alkyl aryl sulfonate salt selected from the group consisting of alkali metal toluene and xylene sulfonates in an amount of from about 4 to 12% by weight, the aqueous composition containing detergent, polyphosphate and lower alkyl aryl sulfonate forming a homogeneous solution having the detergent and polyphosphate fully solubilized therein, and

about 0.1 to 2% by weight of an alkali metal carboxymethylcellulose normally tending to separate from said solution of detergent andpolyphosphate, and hydrogenated caster oil in an amount from about 0.1 to 1% by weight and sufiicient to inhibit the separation of said carboxymethylcellulose salt and assist in maintaining the product substantially homogeneous. A preferred embodiment relates to the mixture of said cellulose salt and hydrogenated castor oil dispersed in an aqueous liquid containing an alkali metal anionic sulfonated detergent such as a higher alkyl benzene sulfonate, a potassium polyphosphate selected from the group consisting of pyrophosphates and tripolyphosphates in an amount normally. soluble in the amount of Water present, a water-soluble hydrotropic aryl sulfonate and a higher fatty acid alkylolamide in proportions to form a substantially homogeneous product.

Such product exhibits many desirable characteristics including, particularly, the improved stability against separation of the carboxyalkylcellulose. The product is maintained in substantially homogeneous condition upon aging. This improved stability is exhibited upon storage for long periods of time at normal room temperature and upon testing at elevated temperatures and upon cooling and permitting the product to return to room temperature as compared to similar products free from said Wax. The composition is pourable and free-flowing from the container without the necessity for shaking to increase fluidity or homogeneity. The product may be utilized conveniently by the consumer by the addition of small portions to a laundering bath or the like and by reason of the substantial homogeneity of the liquid each such small portion will have practically the same composition. It exhibits a washing power during laundering which is comparable to the commercial heavy-duty detergents in powdered form. The liquid may be employed in any suitable container or packaging material such as metal, glass or plastic in the form of bottles, cans, drums or bags.

These compositions contain an organic detergent selected from the group consisting of the water-soluble anionic organic sulfonated detergents (including the sulfates and sulfonates), and non-ionic organic detergents. These materials are known and have sufiicient water solubility or dispersibility to form foaming and detersive aqueous solutions in the concentrations which are suitable for use, e.g., in washing dishes, laundry and the like. They may be used individually or in any desired combination.

Among suitable synthetic detergents are water-soluble higher alkyl aryl sul-fonates, particularly those having 8 to 15 carbon atoms in the alkyl group. It is preferred to use the higher alkyl benzene sulfonate detergent for optimum eifects, though other similar detergents having a mononuclear aryl nucleus, such as toluene, xylene, or phenol, may be used also. The higher alkyl substituent on the aromatic nucleus may be branched or straight-chained in structure, examples of such substituents being nonyl, dodecyl and pentadecyl groups derived from polymers of lower monoolefins which are branched chain, and decyl, keryl, and the like which are straight chain.

Another type of suitable detergent is the sulfated higher alkyl phenol-ethylene oxide condensates having an average of about 46 moles of ethylene oxide per phenol group and about 8 to 10 carbons in the alkyl group. Other similar materials are the alkyl phenolethylene oxide non-ionic detergents which are sulfated.

Examples of suitable aliphatic detergents are the normal and secondary higher alkyl sulfate detergents, particularly those having about 8 to 15 carbons in the fatty alcohol residue, such as lauryl (or coconut fatty alcohol) sulfate. Other suitable detergents are the sulfuric acid esters of polyhydric alcohols incompletely esterified with higher fatty acids, e.g., coconut oil monoglyceride monosultate;

the higher fatty acid esters of low molecular weight alkylol sulfonic acids, e.g., oleic acid ester of isethionic acid; the higher fatty acid (e.g., coconut) ethanolamide sulfate; the higher fatty acid amide of amino alkyl sulfonic acids, e.g., lauric acid amide of taurine; and the like.

These sulfate and sulfonate detergents are used preferably in the form of their alkali metal salts, such as sodium and potassium salts. Other water-soluble salts such as the nitrogen-containing salts, e.g., lower alkylolamine salts, may be used also, examples being the ammonium, isopropanolamine, mono and tri-ethanolamine salts of the detergents.

Examples of suitable non-ionic detergents are the watersoluble non-ionic polyalkylene oxide detergents. In general, these detergents are the products produced by the introduction of a controlled number of alkylene oxide groups into an organic hydrophobic compound or group, usually of an aliphatic or aromatic structure. The hydrophobic organic group contains usually at least about 8 carbons, and preferably up to 30 carbons, condensed with at least about 5 and usually up to about 50 alkylene oxide groups. It is preferred to use the polyalkylene oxide condensates derived from ethylene oxide, although other lower alkylene oxides such as propylene oxide, butylene oxide and the like having generally similar properties may be substituted therefor.

Among the non-ionic detergents, it is preferred to use the polyalkylene oxide condensates of alkyl phenol, such as the polyoxyethylene ethers of alkyl phenols having an alkyl group of at least about 6, and usually about 8 to 12 carbons, and an ethylene oxide ratio (number of moles per phenol) of about 7.5, 8.5, 11.5 and 20, though the number of ethylene oxide groups will be usually from about 8 to 18. The alkyl substituent on the aromatic nucleus may be di-isobutylene, diamyl, polymerized propylene, dimerized C -C olefin, and the like.

Further suitable detergents are the polyoxyalkylene esters of organic acids, such as the higher fatty acids, rosin acids, tall oil acids, or acids from the oxidation of petroleum, etc. These polyglycol esters will contain usually from about 12 to about 30 moles of ethylene oxide or its equivalent and about 8 to 22 carbons in the acyl group. Suitable products are refined tall oil condensed with 16 or 20 ethylene oxide groups, or similar polyglycol esters of lauric, stearic, oleic acids, etc.

Additional non-ionic agents are the polyalkylene oxide condensates with higher fatty acid amides, such as the higher fatty acid primary amides, monoand di-ethanolamides. Suitable agents are coconut fatty acid amide condensed with about 10 to moles of ethylene oxide. The fatty acyl group will have similarly about 8 to 22 carbons, and usually about 10 to 18 carbon atoms, in such products. The corresponding sulfonamides may be used also if desired.

Other suitable polyether non-ionic detergents are the polyalkylene oxide ethers of higher aliphatic alcohols. Suitable fatty alcohols having a hydrophobic character, preferably 8 to 22 carbons, are lauryl, myristyl, cetyl, searyl and oleyl alcohols which may be condensed with an appropriate amount of ethylene oxide, such as at least about 6, and preferably about 10-30 moles. A typical product is oleyl alcohol condensed with about 12, 15 or 20 moles of ethylene oxide. The corresponding higher alkyl mercaptans or thioalcohols condensed wtih ethylene oxide are suitable in the present invention also. The water-soluble polyoxyethylene condensates with hydro phobic polyoxypropylene glycols may be employed also.

The proportion of organic detergent material in the final composition is variable to some extent but it has been found that amounts from about 5 to about 30%, preferably about 10 to 25% by weight, are highly satisfactory with respect to both the physical appearance and performance of the product.

The water-soluble alkaline inorganic polyphosphate salts which have the property of inhibiting precipitation of calcium and magnesium material in aqueous solution and of contributing to the heavy-duty performance of the liquid detergent product, may be considered as derived from orthophosphoric acid or the like by the removal of molecularly-bound water, though any suitable means of manufacture may be employed if desired. Such complex or molecularly dehydrated polyphosphate salts may be used in the form of the normal or completely neutralized salt, e.g., pentapotassium tripolyphosphate, or partially neutralized salt, e.g., potassium acid tripolyphosphate. It is preferred to use the pentapotassiu-m tripolyphosphate and tetrapotassium. pyrophosphate salts including any desired combination of the same.

These polyphosphate salts should be employed in substantial amount such that the addition of a small portion of the liquid product to a washing bath will result in effective detergency and washing power. In the present invention, these polyphosphate salts are present in amounts which are fully soluble in the amount of water present in the product so that the phosphates may be considered to be in solution in the water. The amount of the polyphosphates will be with the range of about 10 to 30% by weight and preferably about 15 to 20%.

The detergent and polyphosphate should be dissolved or solubilized in the water so as to form a solution which is therefore a clear liquid in the absence of the carboxymethylcellulose and castor wax. In the formulation of the product, these ingredients should be suitably selected and proportioned so that they are compatible in the composition using, if desired or necessary, a suitable solubilizing or coupling agent.

The inclusion of a suitable water-soluble dispersing agent or hydrotropic substance is effective in promoting the compatibility of the ingredients so as to form a homogeneous liquid product. The water-soluble hydrotropic 'aryl sulfonates, particularly the alkali metal lower alkyl aryl sulfonate salts are effective in these products. It is preferred to employ the sodium and potassium toluene and xylene sulfonate salts. Sulfonates made from xylene include orthoxylene sulfonate, metaxylene sulfonate, paraxylene sulfonate and ethylbenzene sulfonate. The hydrotrope is employed in a variable amount depending upon the other ingredients but will be used usually in an amount from about 4% to about 12%, preferably about 4 to 8% by weight of the composition.

It is desirable to incorporate a higher fatty acid alkylolamide, such as the monoethanolamides, diethanolamides and isopropanolamides having about 10 to 14 carbon atoms in the acyl radical. Examples are the coconut or equivalent lauric, capric and myristic diethanolamides, monoethanolamides and isopropanolamides. These materials will be used so as to be compatible in the system with suitable amounts being within the range from about 1 to 15%, preferably about 5 to 12%, by weight of the composition. The alkylolamides function primarily to improve the detergency and modify the foaming power of the compositions.

The water-soluble carboxyalkylcellulose material is usually an alkali metal salt of a carboxy lower alkyl cellulose, the alkyl group having up to 3 carbons generally. In general, these materials act as soil anti-redeposition agents during Washing of soiled articles. It is preferred to use the water-soluble salts of carboxymethylcellulose, such as the sodium and potassium salts. Sodium carboxymethylcellulose and the like are available usually in the form of powders in various grades of purity and viscosity in solution. The commercial grades of sodium carboxymethylcellulose having a purity from about 60 to on a dry basis and which are of low, medium or high viscosity may be employed. The degree of substitution of the carboxymethyl group per anhydroglucose unit in the cellulose molecule is variable, but is usually from about 0.5-0.9, and preferably about 0.5-0.7 substitution for highly effective soil suspending properties. This material is used in a.

minor amount such "as from 0.1 to about 2%, and preferably from about 0.25 to 1.5% by weight of the composition.

The hydrogenated castor oil (viz, castor wax) is employed in a minor amount such as about 0.1 to 1% by weight, and sufficient to inhibit separation of the cellulose compound from the bulk of the liquid. It has a melting point of about 8487 C. and is available in a finelydivided form having an iodine number of about 6% maximum. Other characteristics of the preferred grade are an acid value of 0.2% maximum and a sa'ponification value of 17.5l8.5% KO-H with a specific gravity at 20 C. of 0.98-1.00.

The solids content of the liquid product is variable but is usually Within the range of about 20 to 60%, and preferably about 35 to 50% by Weight. The water is in an amount from 40 to 80% and sufficient to normally dissolve the polyphosphate and form a homogeneous product with maintenance of the cellulose and castor wax in homogeneous dispersion.

The liquid detergent product is prepared in any suitable manner. In general, it is preferred to prepare initially an aqueous solution or slurry of the detergent and hydrotrope. The hydrotrope may be added to the detergent as a powder or aqueous mixture. The cellulose material may be added similarly in the form of an aqueous solution or powder with sufficient stirring to insure that a uniform mixture is obtained with finely-dispersed cellulose material, such as in colloidal or molecular dispersion. The temperature of the admixture is not critical and room temperatures or reasonably elevated temperature conditions may be employed as desired. The polyphosphate is added as a powder or it may be predissolved in water, followed by addition of the alkylolamide and castor wax. The latter and solid alkylolamide are preferably added as a mixture in molten form with agitation to form the homogeneous product.

Various other ingredients may be added as desired including compatible perfumes, coloring materials, corrosion or tarnish inhibitors, germicides, bleaching agents, optical bleaches or fluorescent dyes, viscosity modifiers and the like. Other phosphate materials or builder salts may be included in the product provided they do not substantially adversely affect the desired results.

The following examples are additionally illustrative of the nature of the invention and it will be understood that the invention is not limited thereto. All parts are in approximate percent by weight unless otherwise specified.

EXAMPLE I Ingredients: Percent Sodium dodecyl benzene sulfonate 10.0 Tetrapotassium pyrophosphate 20.0 Lauric isopropanolamide 5.0 Sodium toluene sulfonate 6.5 Sodium carboxymethylcellulose 0.5 Castor Wax 0.3 Sodium silicate 3.0 Water Balance This product is prepared by admixing an aqueous solution of the dodecyl benzene sulfonate detergent (the dodecyl group being derived from a propylene tetramer) of about 88% purity, the balance being primarily sodium sulfate impurity, with aqueous solutions of the toluene sulfonate and the sodium silicate (Na O:SiO ratio of 1:2.35) to form a homogeneous mixture. The carboxymethylcellulose of about 65% purity and about 0.7 carboxy groups per glucose unit is dissolved in Water to form a 2.5% solution which is added to the batch at room temperature with stirring. The mixture is heated to 160 F. with stirring and the pyro'phosphate is added in powdered form and mixed until it is dissolved in the aqueous medium. The lauric isopropanolamide and the castor wax are premelted and added as a blend to the above solution at 160 F. with stirring to form a uniform mixture. The

product is finally cooled to room temperature and color and perfume are added as desired.

This product exhibits satisfactory stability upon aging. It shows no separation after storage for long periods of time at room temperature and remains substantially homogeneous after being subjected to elevated and depressed temperature conditions.

EXAMPLES II-III Similar heavy-duty liquids are prepared according to the following formulations:

Ingredients II III (percent) (percent) Sodium dodecyl benzene sulfonate... 10.0 10.0 Tetrapotassium pyrophosphate 20. 0 20. 0 Sodium xylene sulfonate.. 8.0 Sodium toluene sulfonate 8. 0 Sodium carboxymethylcellulose 0. 5 0. 3 Sodium silicate a a 2. 9 Laurie isopropanolamide 5. 0 5. 0 Castor wax 0.3 O. 5 Water Bal. Bail.

The same procedure of manufacture is followed as in Example I with the following modifications: The carboxymethylcellulose solution is added to the sulfonate mixture with stirring at F. and the mixture is heated to F. to form a homogeneous solution, followed by addition of the phosphate and blend of amide and castor wax. The batch is cooled to 90 F. and the sodium silicate (Na O:SiO ratio of 1:2.5 8) is then added in Formula III as a 44% aqueous solution resulting in 2.1% Si0 in the finished product. Perfume and color are then added similarly in very small amounts as desired.

The product of Example II has a pH of 10.3 and the product of Example III has a pH of 11. 6. They exhibit satisfactory stability upon aging at normal temperatures and under adverse temperature conditions. They exert effective washing power for cleansing of soiled articles upon addition of small quantities of each liquid to washing baths.

EXAMPLES IV-VI Other satisfactory liquid detengents are prepared simi: larly according to the following formulations:

Ingredients IV V VI (percent) (percent) (percent) Sodium higher alkyl benzene sulfonate 10. 0 13. 0 9. 0 Sodium nonyl phenol ethylene oxide sulfate 6. 0 Sodium xylene sulfonate 8. 5 6. 75 6. 75 Potassium toluene sulfonate 2. 25 2. 2 Tetrapotassium pyrophosphate.-. 20. 0 15.0 15.0 Higher fatty acid diethanolamide. 2. 5 2. 5 3.0 Higher fatty acid isopropanolamide 2. 5 2. 5 3. 0 Sodium carboxymethylcellulose 0. 5 0.5 0. 5 Castor wax 0. 3 0.3 0.3 Water Ba]. Bal. Bal.

In the above formulations, the higher alkyl group of the alkyl benzene sulfonate is derived from propylene polymer containing mixtures of propylene tetramer and propylene pentamer corresponding on the average to a tridecyl group. The nonyl phenolethylene oxide sulfate has an average number of 5 ethylene oxide groups per nonyl phenol. The higher fatty acid diethanolamide and isopropanolamide each contain about 1:1 mixtures of lauric and myristic acyl groups. The car-boxymethylcellulose has about 0.7 carboxy groups as described. It is understood that these products may contain compatible amounts of perfume, color and fluorescent dye as desired.

Although the present invention has been described and illustrated with a reference to specific examples, it is understood that modifications and variations of composition and procedure are contemplated Within the scope of the appended claims.

What we claim is:

1. A substantially homogeneous, pourable, heavy-duty aqueous liquid detergent composition which consists essentially of alkali metal anionic organic sulfonated detergent containing a long chain of at least 8 carbon atoms in an amount from about to 30% by weight, a potassium polyphosphate salt in an amount from about 10-30% by weight and normally soluble in the amount of Water present, and as a hydrotrope a lower alkyl aryl sulfonate salt selected from the group consisting of alkali metal toluene and Xylene sulfonates in an amount of from about 4 to 12% by weight, the aqueous composition containing detergent, polyphosphate and lower alkyl aryl sulfonate forming a homogeneous solution having the detergent and polyphosphate fully solubilized therein, and about 0.1 to 2% by weight of an alkali metal carboxymethylcellulose normally tending to separate from said solution of detergent and polyphosphate, and hydrogenated castor oil in an amount from about 0.1 to 1% by weight and sufiicient to inhibit the separation of said carboxymethylcellulose salt.

2. A substantially homogeneous, pourable, heavy-duty aqueous liquid detergent in accordance With claim 1 which contains about 1-15% of a higher fatty acid alkylolamide having 10 to 14 carbon atoms in the acyl radical and up to 3 carbons in the alkylol group.

3. A substantially homogeneous, pourable, heavyduty aqueous liquid detergent composition which consists essentially of an alkali metal higher alkyl benzene sulfonate detergent having about 8 to 15 carbon atoms in the alkyl group in an amount from about 5 to 30% by Weight, a potassium polyphosphate salt in an amount from about 10-30% by weight and normally soluble in the amount of water present, and as a hydrotrope a lower alkyl aryl sultonate salt selected from the group consisting of alkali metal toluene and xylene sulfonates in an amount of from about 4 to 12% by weight, the aqueous composition containing detergent, polyphosphate, and lower alkyl aryl sulfonate forming a homogeneous solution having the detergent and polyphosphate fully solubilized therein, and about 0.1 to 2% by weight of an alkali metal carboxy methylcellulose normally tending to separate from said solution of detergent and polyphosphate, and hydrogen ated castor oil in an amount from about 0.1 to 1% by Weight and sulficient to inhibit the separation of said carboxymethylcellulose salt.

4. A substantially homogeneous, poura'ble, heavy-duty aqueous liquid deter-gent in accordance with claim 1 wherein said polyphosphate salt is tetrapotassium pyrophosphate.

5. A substantially homogeneous, pourable, heavy-duty aqueous liquid detergent composition which consists essentially of a water-soluble anionic organic sulfonated detergent in an amount from about 5 to 30% by weight, said detergent comprising an alkali metal higher alkyl benzene sulfonate having about 8 to 15 carbons in the alkyl group, potassium pyrophosphate in an amount from about 10 to 30% by weight and normally soluble in the amount of water present, as a hydrotrope an alkali metal lower alkyl aryl sulfonate salt selected from the group consisting of sodium and potassium toluene and Xylene sulfomates in an amount from about 4 to 12% by weight, a higher fatty acid alkylolamide having 10 to 14 carbon atoms in the acyl group and selected from the group conisting of diethanolamides, monoethanola-mides and isopropanolamides in an amount from about 1 to 15% by weight, the aqueous composition containing detergent, polyphosphate, lower alkyl aryl sulfonate and fatty acid alkylolamide forming a homogeneous solution having the detergent and polyphosphate fully solubilized therein, and about 0.1 to 2% by Weight of sodium carboxymethylcellulose normally tending to separate from said solution of detergent and polyphosphate and about 0.1 to 1% by weight of hydrogenated castor oil.

References Cited UNITED STATES PATENTS 2,674,580 4/ 1954 Henkin 252-117 2,770,599 11/1956 Henkin 252-1 17 2,994,665 8/1961 Reich et al. 252l37 3,101,324 8/1963 Wixon 252138 FOREIGN PATENTS 800,705 9/ 1958 Great Britain.

LEON D. ROSDOL, Primary Examiner.

ALBERT T. MEYERS, SAMUEL H. BLECH,

I. GLUCK, Assistant Examiners.

Claims (1)

1. A SUBSTANTIALLY HOMOGENEOUS, POURABLE, HEAVY-DUTY AQUEOUS LIQUID DETERGENT COMPOSITION WHICH CONSISTS ESSENTIALLY OF ALKALI METAL ANIONIC ORGANIC SULFONATED DETERGENT CONTAINING A LONG CHAIN OF AT LEAST 8 CARBON ATOMS IN AN AMOUNT FROM ABOUT 5 TO 30% BY WEIGHT, A POTASSIUM POLYPHOSPHATE SLAT IN AN AMOUNT FROM ABOUT 10-30% BY WEIGHT AND NORMALLY SOLUBLE IN THE AMOUNT OF WATER PRESENT AND AS A HYDROTROPE A LOWER ALKYL ARYL SULFONATE SALT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL TOLUENE AND XYLENE SULFONATES IN AN AMOUNT OF FROM ABOUT 4 TO 12% BY WATER, THE AQUEOUS COMPOSITION CONTAINING DETERGENT, POLYPHOSPHATE AND LOWER ALKYL ARYL SULFONATE FORMING A HOMOGENEOUS SOLUTION HAVING THE DETERGENT AND POLYPHOSPHATE FULLY SOLUBILIZED THEREIN, AND ABOUT 0.1 TO 2% BY WEIGHT OF AN ALKALI METAL CARBOXYMETHYLCELLULOSE NORMALLY TENDING TO SEPARATE FROM SAID SOLUTION OF DETERGENT AND POLYPHOSPHATE, AND HYDROGENATED CASTOR OIL IN AN AMOUNT FROM ABOUT 0.1 TO 1% BY WEIGHT AND SUFFICIENT TO INHIBIT THE SEPARATION OF SAID CARBOXYMETHYLCELLULOSE SALT.