US 3901832 A
Description (OCR text may contain errors)
United States Patent Dug an et al.
[ Aug. 26, 1975 DETERGENT CAKE CONTAINING MONOALKYLSULFOSUCCINATE AND PREPARATION Inventors: Bernard Baron Dugan, Bryanston;
Coenraad Jacobus Beukes Scholtz, Kempton Park, both of South Africa Assignee: Colgate-Palmolive Company, New
Filed: Oct. 10, 1972 Appl. No.: 296,414
Related US. Application Data Continuation of Ser. No. 14,765, Feb. 26, 1970,
.abandoned, which is a continuation-in-part of Scr.
No. 568,107, July 27, I966, abandoned.
Foreign Application Priority Data Aug. 24, 1965 South Africa 64/4601  References Cited UNITED STATES PATENTS 2,316,234 4/1943 Flett 260/481 2,373,863 4/1945 Vitalis... 252/538 2,567,159 9/1951 Vitalis... 252/161 2,678,921 5/1954 Turck 252/161 2,972,583 2 /1961 Hewitt 252/161 FOREIGN PATENTS OR APPLICATIONS 1,489,582 7/1967 France 252/557 1,636,462 5/1950 United Kingdom. 252/557 544,747 8/1957 Canada 252/557 OTHER PUBLICATIONS 55356j, Bar Detergents, Chemical Services.
Primary Examiner-Stephen J. Lechert, Jr. Attorney, Agent, or Firm-Kenneth A. Koch, Esq.; Murray M. Grill, Esq.; Herbert S. Sylvester, Esq.
[ 5 7 ABSTRACT A process for the production of detergent cakes containing a monoalkylsulfosuccinate and a plasticizer in which a monoaklyl ester of a betenedioic acid is reacted with a sul-fite in the presence of a plasticizer in the liquid state and the article formed thereby.
9 Claims, No Drawings DETERGENT CAKE CONTAINING MONOALKYLSULFOSUCCINATE AND PREPARATION This is a continuation of application Ser. No. 14,765, filed Feb. 26, 1970, now abandoned, which application was a continuation of application Ser. No. 568,107 filed July 27, 1966 and now abandoned.
This invention relates to cleansing bars containinga sulfosuccinate detergent, and, more particularly, the invention is concerned with a process for the'production of detergent cakes containing a monoalkyl sulfosuccinate and suitable for use as cleansing bars, and to the detergent cakes per se. 1 I
The process of this invention enables the production of superior cakes in a simple, economical, and facile manner whereby such detergent cakes may be formed in the equipment normally used and present in any soap making operation, even those operations where modern processing equipment is not available. Accordingly, the capital equipment cost for converting in accordance with this invention a soap bar'production facility to a detergent bar production facility is negligible or nonexistent. The raw materials required for=the production of detergent cakes by the process of this invention are readily available and inexpensive. The detergent cakes formed by the process of this invention are of an exceptionally high quality, and provide a quick and desirable amount of foam. The detergent cake both wet and dry has substantially the same tactile characteristics and density as a normalsoap bar, and the detergent cake, when used in a body of hard water,- results in a complete absence of any objectionable adherent scum or curd such as that which clings to the sides of a bathtub and forms a ring thereon, but the detergent confers a translucence to water of the type formed by soap thereby making it readily evident that the water has been used. In addition, the detergent cakes of this invention can be free or substantially free from inorganic salts and therefore do not feel gritty and are devoid of undesirable efflorescene. I
It is an object of this invention to provide a novel method for the manufacture of a cleansing cake containing a monoalkyl sulfosuccinate.
It is a further object of this invention to produce a novel cleansing bar containing a monoalkyl sulfosuccinate and a plasticizer.
In accordance with the invention, a solid detergen bar is formed by a process including the steps of reacting a monoalkyl ester of butenedioic acid with a sulphite at an elevated temperature and in the presence of a molten plasticizer of the type specificallyset forth hereinbelow, cooling the mass to thereby form a prod uct containing a substantially neutral water soluble salt of a sulfosuccinate monoester of the type described in detail hereinbelow in admixture with the plasticizer, and then processing the solid on conventional soap processing equipment thereby to form the product into cake or bar form.
The monoalkyl sulfosuccinates useful in the present invention are desirably formed by the reaction of a higher molecular weight alcohol with a .butenedioic acid or anhydride such as maleic anhydride or acid or fumaric acid. The high molecular weight alcohol is preferably lauryl alcohol or a mixture of alcohols in which lauryl alcohol predominates. Preferably, the law ryl alcohol is reacted with maleic anhydride to form the monolaurylester of maleic acid. The lauryl maleate is then reacted with a sulphite such as sodium sulphite to produce disodium lauryl sulfosuccinate. The reaction between the lauryl maleate and the sodium sulphite is preferably carried out with the lauryl maleate dissolved or dispersed in a molten plasticizer such as glyceryl monostearate, although the plasticizer may be added subsequent to the reaction. v I
The product of the reaction along with the plasticizer is capable of being used as such or with additives such as perfumes, opacifiers,and the like for forming detergent bars. It will be appreciated that these relatively inexpensive, easily obtainable materials can be reacted in readily available equipment asiunsophistic ated as a kettle, yet form :a highly desirable product. Thus, maleic anhydride is simply reacted with a suitablealcohol to provide the ester, the latter is then diluted with the plasticizer and then the 'maleic acid half-ester is reacted with thesulphite to produce the corresponding sulfosuccinate mono ester which'is substituted according to the sulphite used. Thus, for exampleQdisodiumalkyl sulfosuccinate is produced when sodium sulphite is used. In place of the sodium sulphite there may desirably be used other alkali metal or ammonium sulphites, or alkaline earth metal sulphites, and bisulphites.
While lauryl alcohol and mixtures of alcohols containing lauryl alcohol (as derived from petrochemicals, coconut oil or palm kernel oil, hydrogenated if desired) are preferred, it is possible to use reactants containing an acyclic radical having 12 carbon atoms and a suitable moiety which will link such acyclic radical to the butenedioic acid, such as for example lauric monoethanolamide or lauric diethanolamide. The'acyclic chain of the said reactant may be comprised solely of twelve carbon atoms, or the reactant used may comprise mixtures in which the size of the acyclic chain varies from 12 to l8 carbon atoms. In such mixtures, however, a predominant portion of the acyclic chains must have twelve carbon atoms. By predominant portion it is meant that at least 20 percent and preferably 50 percent of the acyclic chains contain 12 carbon atoms. The compound used must, however, have a reactive hydroxyl group.
The monoalkyl sulfosuccinate (as used herein the term monoalkyl refers to radicals formed from alcohols and hydroxyl bearing equivalents thereof as described" in the paragraph immediately above) should be present in an amount of about 40 to 95 percent by weight of the detergent mass; i.e. before the addition of nonessential'additives such as perfume, color, etc. Preferably, the half ester is present in van amount of between about 60 and percent by weight.
:The plasticizing agent, which advantageously will also be-used as a reaction medium for the reacting constituents, is desirably awaxy or wax-like material such as a glyceryl mono ester, and is preferably glyceryl monostearate.- (Commercial glyceryl -monostearate produced by acid-catalyzed glycerolysis of commercial stearic acid is eminently satisfactory. As compared to monoglycerides produced by alkali-catalyzed glycerolysis, such material is soap-free and, therefore, non-selfemulsifying.). Any organic compound which is a solid orsemi-solid at ordinary temperatures, which melts at the reaction temperature to provide an oily liquid defining the medium in which the reaction is carried out in place of water, and. which is of the high boiling, nonvolatile type having solubility or dispersibility in water may be used. The plasticizer should be sufficiently hydrophilic to produce an emulsion when the final detergent cake product is used in water. The plasticizing agents that can be used should also be resistant to crys tallization and segregation under the different temperature and aging conditions to which the detergent bar or cake may be subjected during storage and use. These plasticizing substances which are solid or semi-solid and which maintain a more or less definite form at ordinary temperatures are hereinafter referred to as normally solid substances.
Organic compounds which function satisfactorily as plasticizing agents and which broaden the plasticity range, as aforementioned, are the high molecular weight fatty acid esters of polyhydric alcohols. For example, long-chain polyhydric alcohol monoand distearates and particularly the ether-alcohol fatty acid esters, i.e. diethylene glycol monoand di-stearates, are especially useful. These compounds are emulsifying agents, and promote the formation of a synthetic detergent bar having a smooth, uniform texture throughout. Other organic plasticizing agents which may be used are those normally solid glycerol mono esters of coconut fatty acids; ethylene glycol di-stearate, and the diethylene glycol monoand di-esters of palmitic, myristic, oleic, lauric and coconut oil acids as well as the corresponding hydrogenated fatty acids; propylene glycol monoand di-esters of stearic, cleic, laurie, myristic, palmitic, coconut oil fatty acids as well as the corresponding hydrogenated fatty acids, etc., as well as suitable glyceryl and ethylene glycol mono esters of such fatty acids, and the like, which esters are normally solid, and which dissolve in water but at a slow rate. Also suitable is a paraffin wax containing a polar compound which under the conditions of use of the bar will be sufficiently dispersed or emulsified. Mixtures of the various organic compounds may, of course, be employed. Where, however, substances are used which are readily dissolved in water there is a tendency towards the production of a bar which is not as firm and dry to the touch as otherwise, and the finished bar or cake dissolves less slowly in water.
A detergent bar, which contains a plasticity modifying agent as herein described, may gradually harden upon standing in the air at room temperatures without changing-its other physical properties or its chemical properties. It is preferred, however, to use a product such as glyceryl monostearate which is sufficiently hydrophilic to produce an emulsion when the final product is dissolved in water. Preferably a glyceryl monostearate derived from hydrogenated tallow oil is used, in which instance there is a substantial proportion of palmitic acid rather than one which is derived from hydrogenated ground nut oil which contains almost all stearic acid. In determining which plasticizer is to be used, a balance should be struck between hydrophilic and emollient properties. For example. it has been found that glyceryl monostearate is compatible with the production of an excellent foam and and the complete absence of adherent scum and leaves the hands with a dry and rather talc-like feel while tallow alcohol leaves the hands with a slightly more emollient feeling. The tallow alcohol may be treated to form the ethylene oxide adduct thereof. Another desirable plasticizer that may be used in compatible amounts is the ethylene oxide adduct of hydrogenated tallow fatty acids.
The required proportion of plasticizer varies depending upon the composition to be plodded and the plasticizing agent employed. The use of amounts of plasticizer of from about 5 to 60 percent by weight of the detergent mass may be utilized to advantage, and amounts of between 20 and 30 percent are highly desirable with an amount of about 25 percent being preferred. Moisture may be present in the final 'product in an amount up to about [0 percent, the upper limit being determined by the desired hardness of the detergent cake. The greater the quantity of moisture, the softer the bar.
In addition to the essential ingredients set forth above, other toilet cake additives may be incorporated into the mass before it sets too hard and before it is shaped into its final bar form. Thus, inorganic or organic coloring materials, e.g. pigments, dyes, etc., may be utilized to give the plodded detergent cake or bar a pleasing color or tint. Some coloring materials such as titanium dioxide function both as a coloring agent and as a hardener. The titanium dioxide may be used in amounts up to about 2% by weight. Glycerin may be incorporated to impart emollient characteristics to the finished bars or cakes and to enhance their gloss. Olive oil may also be used for this purpose and if desired, germicidal substances which are compatible and stable may be added. Other texture modifying ingredients such as lanolin or aromatic additives such as perfume may also be utilized.
In carrying out the formulation of detergent cakes in accordance with the procedure of this invention the onlyequipment required is that which may be found in any commercial soap making operation. The process of this invention includes the step of admixing a higher molecular weight alcohol of the type described hereinabove with a butenedioic acid or anhydride. This step involves the addition of the alcohol and anhydride or acid to a vat or kettle and the application of sufficient heat to melt the alcohol component and initiate the reaction which, being exothermic, continues of its own accord. During this reaction the temperature preferably is maintained below about 100C. to minimize possible side reactions such as, e.g. diesterification, Diels- Alder type reactions, and the like. The components of the reaction mixture will normally be used in quantities approximating their stoichiometric amounts. The butenedioic anhydride or acid is normally added to the vat after the alcohol component has been melted and the rate of addition thereof can be varied to maintain the reaction mixture at a predetermined temperature preferably between about 55 and C. In the case of maleic anhydride, the temperature is easily controlled in this manner since the latent heat of fusion of the anhydride roughly balances the heat of reaction of the aleohol with the anhydride. Following completion or substantial completion of this reaction, the mass is slowly heated to a temperature between about and C. and the mass is maintained at this temperature for be tween 20 and 90 minutes to ensure completeness of the reaction.
After the reaction mass has been so heated, the plasticizer will advantageously be added with agitation until a clear liquid is formed. The temperature at this point should be approximately 45 to 55C. For convenience sake the mass should be held just above its solidification tcmperature. A predetermined amount of water (at least that quantity necessary to get the sulphite to uid to a jelly-like paste andfinallyto-a stiffsoaplike paste. After a temperature of between-95 and 100C. is maintained for'about-20 to-30 minutes, it may be desirable to add about one percent'of hydrogenfperox ide/130 vols. solution to oxidize .any sulphur dioxide that may be present. When hydrogen; peroxide is added, the mass is stirred for approximately,anotherlO minutes. Any desired additives and adjuvants may be incorporated and the productcanthen be passed to ordinary soap bar production apparatus, where, for example, it may be allowed to cool, or be chilled, ona chill roll, milled with or without additives such as perfume, etc., plodded, cut and stamped. The product formed by the process of this invention is .of high quality, and the cake-formed steps are expedited becauSeLthe composition does not stick to the stamping ,dies or other processing equipment. i
ln order to illustrate certain embodiments of the invention, the following examples are set forth. In the examples, and throughout the specification and claims, all parts are stated as parts by weight of the final product unless otherwise indicated.
EXAMPLE 1 Into a stainless steel reaction vessel fitted with a steam jacket, a gate type stirrer, and simple fume exhaust, there is charged 268 parts by weight of commercial lauryl alcohol and this is heated to between 50C. and 60C. at which temperature it is a free flowing oil. While stirring there is then added 134 parts of maleic anhydride granular solids at such a rate that the temperature remains between 50C. and 60C. The temperature is easily controlled by the rate of addition of the maleic anhydride, the latent heat of fusing of the solid roughly balancing the heat of reaction of the alcohol and the anhydride. ('ommcrcial lauryl alcohol is the alcohol obtained by the catalytic hydrogenation of coconut oil or a fraction thereof from .-which the higher and lower homologues havebeen removed. Such a fraction may consist of 75% C,. CH, and 57: ofa mixture of predominantly C and C or it may be the corresponding similar product obtained by the Ziegler condensation ofethylene. or a very suitable product is a CPI-C", fraction formed as a petroleum hy-product.
During this operation, fumes are exhausted to the atmosphere because a small amount of the anhydride evaporates.
After the addition of the maleic anhydride is completed, the mass is slowly heated, with stirring, until at 85C. it clears to a uniform, pale straw-colored liquid. It is then heated to 95C. which temperature is maintained for 30 minutes, and then 380 parts of neutral, commercial, glyceryl monostearate is added and the whole mass stirred to a clear liquid having a temperature between 60C. and 70C.
(**) By commercial glyceryl monostearate is meant a glyceryl monostearate formed from commercial stearic acid.
Subsequently, 50 parts water, and then 168 parts of powdered anhydrous sodium sulphite are introduced into the vessel. The mass is stirred and the temperature gradually raised to 95-l00C. The mass changes from a mobile liquid to a jelly-like paste and finally to a stiff soap-like paste. After being heated to this temperature for 30 minutes, l0 parts of hydrogen peroxide/130 vols. solution is stirred in to oxidize any remaining sulphur dioxide. After stirring for ten minutes the mass is discharged. It sets to a hard, white soap-like mass constituting an excellent base for a toliet' cake.
' An excellent product is obtained to which is added one" percent each of a dye, and a perfume. The additives are incorporated before the mass sets, the mass is milled and the cakes are then formed in a suitable shape and size by extruding, cutting and stamping. Control of the process is no more difficult that that of any soap manufacturing operation and the constituents used are relatively inexpensive and commercially available. The product is benign to the skin, rapidly forms a highly desirable quantity of foam, has a high detergent activity, and is completely free of adherent scum or curd.
I EXAMPLE 11 ple fume exhaust, there is added 214 parts by weight of a commercial lauryl alcohol and this is heated to 68C. 1
Subsequently, 1 07 parts of maleic anhydride is added and the temperature allowed to rise to 96C., which temperature is maintained for about onehalf hour. During this time any fumes that are formed are exhausted to the atmosphere. There is then added 304 parts of commercial glyceryl monostearate and during such addition, the temperature drops to 60C. Water is then added in an amount of 24 parts by weight and, subsequently, 134 parts of sodium sulphite are added. The exothermic reaction which ensues causes the temperahire to rise to 97C. and the mass puffs up to approximately twice its volume (due to release of sulphur dioxide and steam). The temperature is then maintained between 99 and C. for about /2 hour, by which time the reaction is completed. Approximately 2 parts of 3% hydrogen peroxide solution is then added to scavenge any sulphur dioxide and the mixture is stirred for 10 minutes, following which it is removed from the mixer and passed over a three roll mill (chilled internally by cold water) on which it solidifies. The solidified material is removed in the form of ribbons which are crumbled into chips.
EXAMPLES III VI I The chips formed in Example II above are separated into 4 portions, and each portion is mixed with additives as set forth in Table 1 below. i
*AmounLs of all additives are given in percent by of of the final product.
In each instance after the additives are mixed with the chips, the mixture is passed through a roll mill and crimped. The crimped chips are fed to a conventional single barrel plodder having a worm diameter of 10.2 centimeters. The barrel of the plodder is cooled slightly, and its nozzle is slightly heated. Upon emergence from the nozzle, the product is cut and pressed in the normal manner on conventional soap processing machinery. The composition processes in a manner similar to soap and does not adhere to the die or other equip ment during the processing. All of the bars formed are of high quality. The pH of the bars is 6.2 in the case of Examples 111, IV and V, and 6.1 for the bars of Example VI. All of the bars are characterized by exceptional resistance to slough and erosion, give satisfactory lather, and form no adherent scum or curd when used in a bath.
EXAMPLE Vll Into a reaction vessel equipped with steam jacket and stirrer, 260 parts of cocomonoethanolamide is charged. The temperature is raised to about 55C. and 100 parts of maleic anhydride is added. A temperature of between 50 and 60C. is maintained until the reaction is completed. The end of the reaction is checked by adding a few drops of the reaction product to a dilute solution of Na SO is a test tube, heating the test tube, and shaking. When the half ester reaction between the maleic anhydride and the cocomonoethanolamide is sufficiently complete, it disperses in the solution to give a characteristic, viscous streaming effect and subsequently a clear foaming solution. The half ester of maleic acid is a viscous syrup at room temperature. When the above described test shows the half ester reaction to be complete, 100 parts of tallow alcohol, 45 parts of water, and then 126 parts of finely divided Na S0,, are added. The mass is then heated with agitation to 95-100C. for 30 minutes during which period some S gas was evolved.
The final product set to a firm soap-like mass, with good foaming and emollient characteristics which was formed into a cake by a conventional casting operation.
It will be understood that various changes may be made by those skilled in the art without deviating from the principle and scope of the invention as expressed in the appended claims. The embodiments of the invention in which an exclusive property or privilege 'is claimed are defined as follows:
1. A cleansing bar comprising from about 40 to 95% by weight of substantially neutral water soluble alkali metal, alkaline earth metal or ammonium di-salts of sulfosuccinate mono esters and from about 5 to 60% by weight of a normally solid non-volatile organic plasticizer, said plasticizer having a melting point such that it is molten at about 95C and is chosen from the group consisting of fatty acid esters of polyhydric alcohols,
said esters being the reaction product of a reactant having therein (1) a reactive hydroxyl group and, (2) an acyclic chain having from 12 to 18 carbon atoms wherein between 20 and 100% of said chains are alkyl chains having a chain length of 12 carbon atoms, with an alkali metal, alkaline earth metal or ammonium sulfite, said reaction product being produced in a reaction medium including said plasticizer. I I
2. The cleansing bar of claim 1 wherein said salt is selected from the group consisting of alkali metal and ammonium salts of a monoalkylsulfosuccinate.
3. The cleansing bar of claim 1 wherein said salt is a disodium monoalkylsulfosuccinate.
4. The cleansing bar of claim 1 wherein titanium dioxide is present in an amount up to about 2 percent by weight.
5. A process for the production of cleansing cakes comprising; reacting an alcohol having an acyclic chain of from 12 to 18 carbon atoms wherein between 20 and 100% of said chains are alkyl chains having a chain length of 12 carbon atoms with a reactant chosen from the group consisting of maleic acid, butenedioic acid and fumaric acid to form a monoalkyl ester, reacting said monoalkyl ester with an alkali metal, alkaline earth metal or ammonium sulphite in the presence of about 5 to 10 percent water and a molten plasticizer chosen from the group consisting of fatty acid esters of polyhydric alcohols to form a water soluble di-salt of monoalkylsulfosuccinate; cooling the resulting prodnet, and forming the cooled product into cakes containing between about 40 and by weight of said monoalkylsulfosuccinate and from about 5 to 60% by weight of said plasticizer which plasticizes said monoalkylsulfosuccinate salt.
6. The process of claim 5 wherein said monoalkyl ester is formed by reacting a compound selected from the group consisting of maleic anhydride, fumaric anhydride, maleic acid and fumaric acid with a reactant having therein a reactive hydroxyl group and an acyclic chain having from 12 to 18 carbon atoms wherein at least 20% of said chains are alkyl chains having a chain length of 12 carbon atoms.
7. The process of claim 5 wherein the cooled product is milled, plodded, cut and pressed to form cakes.
8. The process of claim 5 wherein the monoalkyl ester is disodium laurylsulfosuccinate.
9. The process of claim 5 wherein said plasticizer is glyceryl monostearate.