Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
  • C11D17/0008—Detergent materials or soaps characterised by their shape or physical properties aqueous liquid non soap compositions
  • C11D17/0013—Liquid compositions with insoluble particles in suspension
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/20—Organic compounds containing oxygen
  • C11D3/2093—Esters; Carbonates

Definitions

• the present invention relates to a wax-containing liquid detergent composition which comprises essentially a stable homogeneous suspension or dispersion of castor wax and a water-soluble higher alkyl aryl sulfonate detergent in an aqueous medium, and to processes for preparing liquid detergents, as hereinafter described and claimed.
• liquid compositions comprising various detergents and hydrogenated castor oil, as disclosed in US. Patents No. 2,871,193 and No. 2,290,045 for example.
• certain processing details are employed usually such as the operation of the melting of the wax and its addition as a liquid at high temperatures to the other detergent ingredients, the need for comparatively long heating times and certain cooling conditions for the entire composition in order to prepare a fine suspension and minimize a tendency to form a coarse, flaky product.
• stable, homogeneous, fine suspensions or dispersions may be prepared in concentrated form using procedures which are particularly conducive to commercial preparation of a liquid detergent. More particularly, stable concentrates are obtained with the castor wax in extremely fine and homogeneous dispersion or pre-crystallized form comprising essentially about 1 to 18% by weight of the wax and 1 to 25% by weight of a water-soluble higher alkyl mononuclear aryl sulfonate detergent proportioned in an aqueous medium.
• Such concentrates can be prepared by addition of a proportionate amount of castor wax in particulate form with Water in the presence of said sulfonate detergent at an elevated temperature sufiicient to melt the castor wax with agitation and forming a homogeneous liquid solution, and thereafter slowly cooling the mixture until a critical stage of emulsion or suspension formation has passed and to produce a particular phase separation wherein a homogeneous, liquid dispersion of the wax is obtained substantially free from lumps or crystals.
• the invention relates also to a process for forming a substantially homogeneous, pourable, heavy-duty aqueous liquid detergent which comprises essentially about 5 to 30% of water-soluble organic sulfonated detergent, a water-soluble alkaline inorganic polyphosphate salt in an amount from about 5 to 30%, and a minor amount from about 0.1 to 1% by weight of the castor wax by initial formation of a wax-detergent concentrate followed by admixture at a temperature below about 140 F. with said detergent, phosphates in aqueous solution and any other ingredients to form a substantially stable and homogeneous heavy-duty liquid detergent.
• the alkyl aryl sulfonate detergent has a higher alkyl group within the range of 8 to 18 carbons and preferably about 8 to 15 carbon atoms. It is preferred to use the higher alkyl benzene sulfonate, though other similar detergents having a mononuclear aryl nucleus, such as higher alkyl toluene and xylene sulfonates, may be used also.
• the alkyl substituent may be branched, such as nonyl, dodecyl and pentadecyl groups, including mixtures thereof which are derived from polymers of lower-olefins.
• the alkyl group may be straight-chained in structure such as the n-decyl, n-dodecyl and keryl groups. Preferred form of a stable dispersion.
• materials have an alkyl group of 12 to 15 carbons such as tridecyl benzene sulfonate which has a mixture of polymerized olefins in the alkyl group corresponding on the average to about a tridecyl group.
• Such sulfonate detergents are used preferably in the form of their alkali metal salts, such as sodium and potassium salts.
• 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, monoand tri-cthanolamine salts of the detergents.
• the castor wax (viz. hydrogenated castor oil) may be used in any suitable grade. It is preferred to use a material having a melting point of about 8487 C. and is employed in a finely-divided 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 saponification value of 17.518.5% KOH with a specific gravity at 20 C. of 0.98-1.00. Other grades of castor wax can be used also, such as grades having an iodine number up to 8.5 and an hydroxyl number of -165.
• a concentrate of the castor wax and the alkyl aryl sulfonate detergent is prepared. in water in the In general, the process comprises heating an aqueous solution of the detergent to a temperature above F. and sufiicient to melt solid castor wax without an adverse effect on any ingredient, e.g., about -200 F., slowly adding the castor wax in particulate form with rapid agitation until it is molten and there is formed a homogeneous solution. Any suitable particulate form of the wax may be used such as thin flakes, powder, etc.
• the heated mixture may be prepared in a fluid, homogeneous solution form without lumps in a comparatively short time, such as in less than about fifteen minutes, and preferably in not over five minutes.
• the mixture should then be cooled under controlled conditions to crystallize the wax in
• Adjusted conditions to crystallize the wax in
• Adjusted conditions to crystallize the wax in
• Mol. density which is homogeneous and does not readily separate from the liquid upon aging and is free from palpable crystals or the like.
• the heated solution should be cooled slowly with agitation at a rate not substantially in excess of 5 F., and preferably up to 3 F. per minute through a transition temperature range below 160 F., and usually from l30150 F., until a critical stage of emulsion formation occurs wherein the product assumes a smooth, milky appearance which is more viscous and opaque.
• the wax is in such a finely dispersed, almost colloidal-like state that the particles are highly resistant to separation from the liquid.
• the wax droplets which are pre-crystallized in this smooth grain-free emulsion form are in stabilized condition so that they do not coalesce to large crystals upon further cooling or upon aging under reasonable conditions. If the cooling is conducted from the solution state too rapidly, there is formed in the liquid comparatively large crystals or palpable lumps which tend to precipitate from the liquid phase.
• the liquid batch may be cooled more rapidly to room temperature. It may be stored without adverse effects for later use in the manufacture of heavy-duty liquid detergents.
• This suspension should be prepared so as to be in a pourable condition at normal room temperature of about 72 F. in order to facilitate processing.
• Such liquids may vary in viscosity or consistency from a highly fluid to a mobile gel or semi-solid pasty condition so that the fluid mass may flow by gravity or pumped to a mixing vessel for admixture with other ingredients.
• the amount of castor wax and sulfonate detergent in this fine aqueous dispersion is variable and should be proportioned to form a liquid having the desired physical properties.
• the wax is in an amount selected from the range of 1 to 18%, preferably 4 to 14%, by weight and the sulfonate detergent is from 1 to 25%, preferably 2 to 20% by weight, with the balance being primarily water.
• the wax to detergent ratio can be varied as desired with resulting variation in the physical properties. In general, an increase in the wax concentrate tends to produce a more viscous, gel-like product with a given amount of detergent whereas an increase in the detergent tends to result in a more fluid product provided that the solids content is not excessive.
• the amount of water should be sufficient to solubilize the detergent and permit adequate dispersion of the wax under the controlled conditions described, and is preferably at least about 50% by weight of the total concentrate.
• This dispersion may be employed for many uses, including use as an intermediate in the preparation of other detergent (including cosmetic) compositions or use for detergent purposes directly.
• Various selected materials may be added during or after preparation of the dispersion as desired provided the amounts of compatible materials used do not substantially affect the desired properties since the preparation is dependent upon the mutual effect exerted by the specified wax and sulfonate detergent in suitable concentrations under the specified conditions.
• compatible detergents perfumes, coloring materials, corrosion or tarnish inhibitors, soil-suspending materials, optical bleaches or fluorescent dyes, viscosity modifiers or organic solvent materials, and the like.
• the admixture of the dispersion with additional water, particularly, in the presence of added surface-active agent in a suitable amount, does not destroy the stability of the wax in the aqueous medium but produces an aqueous solution in which the wax is in fine, stable suspension to give an attractive opaque to translucent appearance to the liquid product.
• the concentrate can be admixed at room temperature or at moderately elevated temperatures below the point at which the critical phase change of the concentrate occurred upon cooling with detergent to effect homogeneous products. It is preferred to prepare liquids having about 5 to 50% by weight of detergent and 0.1 to 1% of the castor wax in stable dispersion in water. If desired, small amounts of solvent type materials such as ethanol, urea and glycerine may form part of the solvent medium.
• alkyl aryl sulfonate e.g., sulfate or sulfonate
• sulfonated detergents may be added.
• a preferred detergent used in the mixture is the sulfated higher alkyl phenolethylene oxide condensates having an average of about 2 to 18 moles of ethylene oxide per phenol group and about 6 to 18, preferably 8 to 14, carbons in the alkyl group. It is preferred to employ the product having about 4 to 6 moles of ethylene oxide and 8 to 10 carbons in the alkyl group, e.g., nonyl phenol-ethylene oxide sulfate.
• the sulfated products of aliphatic alcohols of 8 to 18 carbons, preferably 10 to 14 carbons, condensed with about 2 to 18 moles ethylene oxide may be used also, the alcohols being fatty alcohols or branched-chain Oxo alcohols, e.g., lauryl ether sulfate with 4 to 6 moles of ethylene oxide.
• Suitable sulfonated synthetic detergents are the normal and secondary higher alkyl sulfate detergents, particularly those having about 8 to carhens in the fatty alcohol residue such as lauryl (or coconut fatty alcohol) sulfate; the sulfuric acid esters of polyhydric alcohols incompletely esterified with higher fatty acids, e.g., coconut oil monoglyceride monosulfate; the higher fatty acid esters of low molecularweight alkylol the higher fatty acid amide of amino alkyl sulfonic 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; higher alkyl glyceryl ether sulfonate, e.g., dodecyl glyceryl ether sulfona'te; and the like.
• non-ionic detergents are the water-soluble non-ionic polyalkylene oxide detergents having an hydrophobic organic group having 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.
• the polyoxyethylene condensates are preferred, although other lower alkylene oxides such as propylene oxide and butylene oxide may be substituted therefor.
• the polyalkylene oxide condensates of alkyl phenol may be used, 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 (No. of moles per phenol) of about 7.5, 8.5, 11.5 and 20.
• the number of ethylene oxide groups will be usually from about 8 to 18.
• Examples of the alkyl substituent on the aromatic nucleus are di-isobutylene, diamyl, polymerized propylene, dimerized C -C olefin, and the like.
• non-ionic detergents are the polyoxyalkylene esters of organic acids such as higher fatty acids, rosin acids, tall oil acids, or acids from the oxidation of petroleum; the polyalkylene oxide condensates with higher fatty acid amides, such as the higher fatty acid primary amides, monoand di-ethanolamides condensed with ethylene oxide and the corresponding sulfonamides; the polyalkylene oxide ethers of higher aliphatic alcohols, such as lauryl, cetyl, oleyl alcohol or 0x0 alcohols which may be condensed with 6-30 moles of ethylene oxide; the higher alkyl mercaptans or thioalcohols condensed with ethylene oxide; and the water-soluble polyoxyethylene condensates with hydrophobic polyoxypropylene glycols.
• organic acids such as higher fatty acids, rosin acids, tall oil acids, or acids from the oxidation of petroleum
• the polyalkylene oxide condensates with higher fatty acid
• a heavy-duty liquid detergent composition containing a water-soluble non-cationic detergent content, preferably of 5-30% by weight of sulfated and/or sulfonated detergents, and a suitable content, e.g., 530% by weight, of water-soluble alkaline inorganic builder salts particularly polyphosphates with a minor proportion of castor wax.
• a water-soluble non-cationic detergent content preferably of 5-30% by weight of sulfated and/or sulfonated detergents
• a suitable content e.g., 530% by weight
• the dispersion is then admixed with the builder salts and other ingredients in added water at a temperature below 160 F., preferably below about F., so as not to adversely affect the dispersion of castor wax but to solubilize the builder salts as desired.
• Any suitable minimum mixing temperature may be em ployed including room temperature depending upon the other ingredients.
• the use of the lower temperature range in this subsequent operation is particularly desirable since the polyphosphates have an increased tendency to hydrolyze or decompose in water at higher temperatures of about F. and above.
• the polyphosphate salts may be in the form of the normal or completely neutralized salt, e.g., pentapotassium tnipolyphosphate, or partially neutralized salt, e.g., potassium acid tripolyphosphate. It is preferred to use the tetrapotassium pyrophosphate and pentapotassium tripolyphosphate or any desired combination of the same.
• the alkali metal salts of tetraphosphoric acid may be used also.
• Other suitable materials which may be employed are sodium tripolyphosphate and its hexahydrate, and tetrasodium pyrophosphate vin suitable proportions so as to form a substantially homogeneous product.
• alkaline builder salts may be employed also such as the soluble alkali metal silicates. These silicates may be employed as the sole builder salt if desired or in suitable combination with the polyphosphates. Suitable silicates are those having an alkali oxide to silica ratio within the range of about 1:1 to 1:4, and preferably from about 1:2 to 1:3. Examples are sodium silicates having an Na O to S ratio of 1:2.35, 1:2.5, 1:3.2, 1:2.0, 1: 1.6 and 1 :1. In general, it is preferred that the builder salts be primarily the poly phosphates so as to avoid the high alkalinity ordinarily produced by substantial amounts of silicates.
• the detergent and builder salt should be formulated so as to form a substantially homogeneous liquid.
• 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 depending upon the proportions.
• a suitable water-soluble hydrotropic substance is effective in promoting the compatibility of the ingredients so as to form a homogeneous liquid product.
• the water-soluble sulfonated hydrotropes particularly the alkali metal sulfonated salts having a lower alkyl group up to about 6 carbons, are effective in these products. It is preferred to employ an aryl sulfonate such as the sodium and potassium toluene and xylene sulfonate salts.
• Sulfonates made from xylene include orthoxylene sulfonate, metaxylene sulfonate, paraxylene sulfonate and ethylbenzene sulfonate.
• xylene sulfonates usually contain metaxylene sulfonate as the main ingredient.
• the hydrotrope is employed in a variable amount depending upon the other ingredients but will be used usually in a suitable amount from about 4%to about 12%, preferably about 4 to 10% by weight of the composition.
• the heavy-duty liquid advantageously contains a soilsuspending material which can be maintained in dispersion in the liquid medium. It has been found that the fine dispersion of castor wax produced by initial formation of the concentrate is effective in stabilizing the soilsuspending agent and minimizing its separation from the liquid, particularly in the case of suspended cellulosic material such as carboxymethylcellulose.
• the alkali metal salt of a carboxy lower alkyl cellulose having up to 3 carbons in the alkyl groups such as the sodium and potassium salt of carboxymethylcellulose.
• the commercial grade of sodium carboxymethylcellulose and the like may be employed.
• Other known water-soluble cellulosic materials are the lower alkyl and hydroxy alkyl ethers such as methylcellulose, ethylcellulose and hydroxyethylcellulose; and the various cellulose sulfate materials.
• soil-suspending agents may be employed such as the water-soluble vinyl polymers.
• water-soluble polyvinyl alcohol which may contain minor amounts of polyvinyl acetate as commercially made.
• Water-soluble polyvinyl polymeric amides such as polyvinylpyrrolidone of suitable molecular weight may be employed also.
• the amount of the soil-suspending agent is usually from about 0.1 to about 2% by weight in the liquid product. It has been found that amounts Within this range can be used in the preparation of substantially homogeneous products which exhibit a high level of soil suspension during washing.
• Various other materials or mixtures may be employed which assist in maintaining the soil-suspending 6 materials in suspension or dispersion in the liquid. Suitable mixtures of cellulosic compounds, or a mixture of a cellulosic compound with a vinyl polymer, or a mixture of a cellulosic compound with castor wax, or any combination thereof, may be employed.
• a higher fatty acid alkylolamide such as the monoethanolamides, diethanolamides and isopropanolamides having about 8 to 18, preferably 10 to .14 carbon atoms in the acyl radical.
• examples are the coconut or equivalent lauric, capric and myristic diethanol amides, 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 2 to 12%, by weight, depending on the composition.
• the 'alkylolamides function primarily to improve the detergency and modify the foaming power of the compositions.
• the liquid detergent product is. prepared in any suitable manner.
• the hydrotropic salts, the polyp hosphate, the soil-suspending agent, and the organic detergents may be mixed in any suitable order in the form of powders, aqueous solutions or slurries to the aqueous medium.
• the alkylolamide is preferably added in molten or liquid form with agitation to form a homogeneous product.
• the wax-detergent concentrate is added at any convenient stage in an amount depending upon the concentration of wax in the concentrate and the proportion desired in the final product.
• the solids content is variable and is usually up to about 50% by weight, with the balance being primarily water.
• the temperature of admixture should be sufficient to dissolve the ingredients and reasonably elevated temperature conditions such as up to the wax transition temperature may be employed.
• Example I Ingredients: Percent Castor wax 10.0 Sodium tridecyl benzene suliionate 2.8 Sodium sulfate 0.4 Water 86.8
• the above sulfonate detergent containing the sodium sulfate as an impurity and the water are mixed and heated to 200 F. in a jacketed vessel.
• the cast-or wax is added in fitake form within a period of 5 minutes with stirring, and the temperature falls to about 190 F. during its addition.
• the resulting mixture is maintained at this temperature with rapid agitation until the wax is melted and a homogeneous mixture formed which is accomplished in about 3 minutes.
• the batch is then cooled slowly at the rate of about 1 F. to 1 /2 F. per minute with continuing agitation until an opaque, creamy, non-grainy emulsion or dispersion is formed at about 140 F.
• the product may then be cooled to room temperature rapidly.
• the final produlot is a smooth, homogeneous, stable, grainfree suspension or emulsion of minute Wax droplets in the mixture and is essentially free from lumps and crystals.
• Example II-V The procedure of Example I is repeated using the ratios of the wax, detergent and Water as specified in the following formulations:
• the above products are homogeneous, stable, grainfree concentrated suspensions having varying viscosrttes depending upon the particular ratio of the wax to base and the amounts employed.
• the products of Examples II-IV are fiowable fluids with the Example II product being the most fluid and the product of Example V being in the form of a flowalble gel.
• Example VI The product of Example I is used to prepare a heavyduty liquid according to the following formulation:
• the product is prepared by mixing the xylene sul fonate in the form of a 30% aqueous solution, the sulfonate detergent in the fiorm of a 54% solid slurry and the sulfated ethoxamer in water While heating to 120-130 F.
• the cellulose compound in powder form is added with agitation followed by the phosphate in the form of a powder or aqueous solution to obtain a homogeneous mixture.
• the amide compounds are added in molten form to the batch followed by the addition of the fluid castor wax-detergent suspension slowly with sufiicient agitation to insure good dispersion and formation of a homogeneous product.
• the batch is permitted to cool to 100 F. and the polyvinyl alcohol solution is added with color and perfume. 'I he fluorescent dye may be added at any desired stage.
• the final product is a stable and homogeneous liquid exhibiting satisfactory aging and cleansing properties.
• the substitution of the wax-detergent concentrates of Examples II-V results in heavy-duty liquids having satisfactory physical properties and washing power also.
• a process which comprises admixing castor wax in particulate form with an aqueous solution of a watersoluble higher alkyl mononuclear aryl sulfonate detergent salt having 8 to 18 carbons in the alkyl group with agitation at a temperature above 160 F. and sufiicient to melt said castor wax and form a homogeneous liquid mixture thereof having about 1 to 18% by weight of said wax and 1 to 25% by weight of said detergent salt, slowly cooling said mixture with agitation at a rate not substantially in excess of 5 F. per minute through a transition temperature below 160 F. until a critical stage of emulsion formation has passed and said mixture forms a stable, homogeneous dispersion substantially free from palpable lumps or crystals.
• a prowss which comprises admixing castor wax in particulate form with an .aqueous solution of an alkali metal higher alkyl benzene sulfonate detergent salt having 8 to 18 carbons in the alkyl group with agitation at a temperature of about 180200 F. and sufiicient to melt said castor wax and form a homogeneous liquid thereof having about 1 to 18% by weight of said wax and 1 to 25% by weight of said detergent salt, cooling said mixture with agitation at a rate not substantially in excess of 5 F. per minute through a transition temperature from about l30l50 F. until a critical stage of emulsion formation has passed and forming thereby a stable, homogeneous dispersion of the wax substantially free from palpable lumps or crystals.
• a process for preparation of a liquid detergent composition which comprises preparing an aqueous concentrate of a stable, fine dispersion of about 1 to 18% by weight of oastor wax and 1 to 25% by weight of a Watersoluble alkyl mononuclear aryl sulfonate detergent salt having 8 to 18 carbons in the alkyl group in water by admixing said castor wax in particulate form with water in the presence of said detergent with agitation at a temperature above F. and sufficient to melt said castor Wax and form a homogeneous liquid mixture and slowly cooling said mixture with agitation at a rate not substantilally in excess of 5 F. per minute through a transition temperature below 160 F.
• a process for preparation of a heavy-duty liquid detergent composition which comprises preparing a stable dispersion concentrate of about 1 to 18% by weight of castor wax and 1 to 25% by weight of a water-soluble alkyl mononuclelar aryl sulfonate detergent salt having 8 to 18 carbon atoms in the alkyl group in water by admixing said castor wax in particulate form with water in the presence of said detergent with agitation at a temperature above 160 F. and sufiicient to melt said castor wax and form a homogeneous liquid mixture and slowly cooling said mixture with agitation at a rate not substantially in excess of 5 F. per minute through a transition temperature below 160 F.
• a process for preparing a detergent composition in the form of a substantially stable, homogeneous, pourable liquid which comprises forming a stable liquid dispersion of about 1 to 18% castor wax and 1 to 25% alkali metal higher alkyl benzene sulfonate detergent salt having 8 to 18 carbons in the alkyl group in water by admixing said oastor wax in particulate form with water in the presence of said detergent with agitation at a temperature above 160 F. and sufiicient to melt the said castor wax and form a homogenous liquid mixture and slowly cooling said mixture with agitation at a rate not substantially in excess of 5 F. per minute through a transition temperature below 160 F.

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Citations (4)

• 0
  • BE BE633047D patent/BE633047A/xx unknown
  • NL NL293394D patent/NL293394A/xx unknown
• 1962
  • 1962-06-01 US US199277A patent/US3242092A/en not_active Expired - Lifetime
• 1963
  • 1963-04-19 AU AU29687/63A patent/AU272305B2/en not_active Expired
  • 1963-05-02 ES ES287598A patent/ES287598A1/es not_active Expired
  • 1963-05-10 GB GB18695/63A patent/GB1034202A/en not_active Expired
  • 1963-05-28 FR FR936230A patent/FR1363507A/fr not_active Expired

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