MXPA06008178A - Novel acylalkylisethionate esters and applications in consumer products - Google Patents

Abstract

The present invention provides acylalkylisethionate esters useful in consumer products. The acylalkylisethionate esters are produced by reacting one or more carboxylic acids with one or more alkyl-substituted hydroxyalkyl sulfonates under esterification reaction conditions. The alkyl-substituted hydroxyalkyl sulfonates used as a raw material in producing the esters are prepared by reacting bisulfite with one or more alkylene oxides.

Description

NOVEDOUS ACILALKILISETIONATE ESTERS AND APPLICATIONS IN CONSUMER PRODUCTS FIELD OF THE INVENTION The present invention relates to the preparation of salts of acylalkyl-isethionate esters, intermediates in their production and their application in consumer products.

BACKGROUND OF THE INVENTION Acylalkyl isethionate esters are anionic surfactants that can be used in a variety of personal care cleaners such as soaps, cosmetic compositions and cleansing formulations. An acylalkyl isethionate ester, sodium cocoyl isethionate ("SCI") is an ester currently used strictly in combination soap bars (ie, synthetic detergent bars) due to its low water solubility and softness (ie, non-irritating) for the skin compared to fatty acid soap bars, rougher. However, due to its low water solubility, SCI is not suitable for use in liquid cleaners. One method to improve the limited water solubility of the SCI is to combine the SCI with other surfactants such as taurate, amphoacetates and betaines. However, this combination of surfactants still produces an opalescent solution that tends to separate when stored. Therefore, it would be desirable to produce acylalkyl-isethionate esters that are highly water-soluble, hydrolytically stable and non-irritating for use in aqueous as well as non-aqueous consumer products such as personal care cleaners.

BRIEF DESCRIPTION OF THE INVENTION The present invention includes alkyl substituted hydroxyalkyl sulfonates and method of preparing alkyl substituted hydroxyalkyl sulfonates. The alkyl-substituted hydroxyalkyl sulfonates can then be reacted with a carboxylic acid to produce acylalkyl-isethionate esters. The acylalkyl-isethionate esters can be used as a surfactant or as an active surface agent in consumer products such as personal care cleaners. The acylalkylisethionate esters of the present invention are at least as mild to the skin as SCI. In addition, unlike SCI, the acylalkyl-isethionate esters of the present invention are low foaming and highly water soluble and hydrolytically stable which makes the esters easier to handle, store and process. Due to their improved solubility properties, the alkyl-substituted acylalkyl-ethionate esters can be dissolved in water or flaked in a fast dispersion concentrate and hence their use in the formulation of aqueous and non-aqueous consumer products, highly desirable BRIEF DESCRIPTION OF THE FIGURES For a detailed understanding and a better appreciation of the present invention, reference should now be made to the following detailed description of the invention, taken together with the accompanying figures. Figure 1 is a graph showing the hydrolytic stability of sodium cocoyl isethionate (SCI), sodium cocoyl ethyl isethionate (SCMI) and sodium cocoylethyl isethionate (SCEI) for a period of 30 days; Figure 2A shows the characteristic foaming of SCMI; Figure 2B shows the characteristic foaming of sodium lauryl ether sulfate (SLES) and sodium lauryl sulfate (SLS); and Figure 3 shows the solubility of solutions containing one of SCI, SCMI and SCEI.

DETAILED DESCRIPTION OF THE INVENTION The present invention provides mild (ie non-irritating) acylalkylcyanate esters with high, compacted, hydropolytically stable, and highly soluble foams useful as a primary or secondary surfactant in aqueous and non-aqueous consumer products such as personal care cleaners . The acylalkyl isethionate ester herein refers to an alkyl substituted acylalkyl isethionate ester in which at least one hydrogen of the alkyl chain of the isethionate portion of the molecule is substituted with an alkyl group. That is, an alkyl group is substituted on at least one carbon atom of the alkane sulfonate portion of the acylalkylcyanation ester. For example, in one embodiment, the alkyl substituted acylalkyl isethionate ester is an alkyl substituted acylalkyl isethionate ester having the following general formula (I): R-COO HCHCH2 s? 3X in which R is any hydrocarbon group having between 4 and 25 carbon atoms; R1 and R2 are each independently selected from the group consisting of hydrogen and an alkyl group of 1 to 6 branched carbon atoms or linear aliphatic which is subject to the proviso that only one of R1 and R2 is an alkyl group of 1. to 6 straight or branched aliphatic carbon atoms while the rest of R 1 or R 2 is hydrogen; and X may be a cationic species present for charge neutrality such as hydrogen, an alkali metal such as sodium, potassium and lithium, calcium, magnesium, zinc, aluminum, ammonium and ammonium ions which are substituted with one or more organic groups. In another embodiment, the acylalkyl-isethionate ester substituted with alkyl is an alkyl substituted acylpropyl isethionate ester having the general formula (II): wherein R is a hydrocarbon group having between 4 and 25 carbon atoms; R1, R2 and R3 are each independently selected from the group consisting of hydrogen and an alkyl group of 1-6 straight or straight aliphatic carbon atoms subject to the proviso that one of R1, R2 and R3 is an alkyl group of 1. to 6 branched or linear aliphatic carbon atoms while the remainder of R 1 or R 2 or R 3 is hydrogen; and X can be any cationic species present for charge neutrality such as hydrogen, an alkali metal such as sodium, potassium and lithium, calcium, magnesium, zinc, aluminum, ammonium and ammonium ions which are substituted with one or more organic groups. The alkyl-substituted acylalkyl-ethionate esters of the present invention can be prepared by direct esterification of one or more alkyl-substituted hydroxyalkyl isethionates with one or more carboxylic acids. The esterification is produced by mixing alkyl-substituted hydroxyalkyl isethionate and carboxylic acid, and optionally an esterification catalyst under esterification conditions. The alkyl substituted hydroxyalkyl isethionate may be present as the salt of the hydroxyalkyl isethionate substituted with alkyl or in its acid form. In this way, the spherification for a modality can be produced according to the reaction: R- X + H2? wherein R is any hydrocarbon group having between about 4 and about 25 carbon atoms, including straight chain, branched, saturated and unsaturated hydrocarbon groups; R1 and R2 can each independently be hydrogen or an alkyl group selected from the group consisting of: alkyl of 1 to 6 carbon atoms, subject to the proviso that both of R1 and R2 are not simultaneously hydrogen and are not simultaneously both an alkyl group of 1 to 6 carbon atoms and wherein X is a cationic species present for charge neutrality, which may be a cationic species but is preferably selected from the group consisting of: hydrogen, alkali metals, alkaline earth metals, zinc, aluminum and ammonium ions which are substituted with one or more organic groups which can be any organic group. When X is hydrogen, alkyl substituted alkyl acid is present, which we have surprisingly found to be catalytic during the esterification. It can be caused that X is present as hydrogen by the addition of any strong acid; however, it is more preferable to add alkyl-substituted alkyl acid by itself in its pure form when added as an esterification catalyst. The alkyl substituted hydroxyalkyl isethionates can be prepared by reacting one or more alkylene oxides with an aqueous solution of bisulfite. The alkylene oxides used to prepare the hydroxyalkyl isethionates may include, for example, propylene oxide, butylene oxide and any higher alkylene oxide. The concentration of the aqueous bisulfite solution can vary from 10% to 70% by weight and can include an aqueous solution of alkali metal bisulfite such as sodium, potassium or ammonium. In one embodiment, the alkyl substituted hydroxyalkyl isethionate is an alkyl substituted hydroxyethane sulfonate produced by the following reaction: or R1R2 f p R CH CH2 + pHS03- - > - q HO-CHCH-S? 3 + rHO-CHCH-S? 3 wherein R is an alkyl group of 1 to 6 carbon atoms, R1 and R2 are each independently selected from the group of hydrogen and an alkyl group of 1 to 6 carbon atoms but only R1 and R2 is hydrogen while the other is an alkyl group of 1 to 6 carbon atoms; R3 and R4 are each independently selected from the group of hydrogen and an alkyl group of 1 to 6 carbon atoms, but only one of R3 and R4 is hydrogen while the other is an alkyl group of 1 to 6 carbon atoms; and q + r is equal to p. In this way, isomers can be produced during the reaction.

Preferably, one or more cations such as sodium, potassium, lithium, magnesium, calcium and ammonium ions are present in the aqueous bisulfite solution to maintain charge neutrality and in fact any ion by which charge neutrality can be carried out. suitably included in the aqueous solution, which includes mono-positive ions, dipositive ions and tripositive ions. In another embodiment, propylene oxide is reacted with sodium bisulfite to produce sodium 2-methyl-2-hydroxyethanesulfonate or sodium 1-methyl-2-hydroxyethane sulfonate or a mixture thereof. In yet another embodiment, butylene oxide is reacted with sodium bisulfite to produce sodium 2-ethyl-2-hydroxyethane sulfonate or sodium 1-ethyl-2-hydroxyethanesulfonate or a mixture thereof. In a further embodiment, a mixture of propylene oxide and butylene oxide is reacted with sodium bisulfite to produce sodium 2-methyl-2-hydroxyethanesulfonate, sodium 2-ethyl-2-hydroxyethanesulfonate, 1-methyl-2- sodium hydroethanesulfonate or sodium 1-ethyl-2-hydroxyethanesulfonate, or mixtures thereof. The propylene oxide and the butylene oxide or the ethylene oxide can be combined in any proportion to obtain the desired amounts of each alkyl substituted hydroxyethane sulfonate. By producing the acylalkylcyanate ester by the reaction of a carboxylic acid with an alkyl isethionate, which is a hydroxyethane sulfonate substituted with alkyl, the carbon atom of the hydroxyethane sulfonate portion of the molecule connected to the oxygen atom of the ester linkage is termed as the "carbon atom of the ester bond". Surprisingly it has been found that when the alkyl isethionate contains a high degree of ester bonding carbon which are secondary carbon atoms, the hydrolytic stability of the final acylalkyl isethionate ester product is substantially increased. No similar increase in hydrolytic stability has been observed with respect to the increase in secondary carbon content of the other carbon atoms directly bonded to the sulfur atom in the alkyl isethionate. Therefore, it is highly desirable to produce an alkyl-substituted hydroxyalkyl isethionate which allows an acylalkyl-isethionate ester produced therefrom to possess a high degree of ester bond carbons which are secondary carbon atoms, as possible. During the production of the alkyl substituted hydroxyalkyl isethionates, the pH of the reaction solution comprising the alkylene oxide and the bisulfite may vary from about 4.0 to 10.0. However, to minimize side reactions and side products such as diols, the pH of the reaction solution can be maintained within a range of 5.5 to 8.5. In addition, the pH of the reaction solution can be maintained optimally at a pH of about 7.0 to maximize the production of alkyl substituted hydroxyalkyl isethionate having a high content of secondary ester bond carbons. To maintain the pH of the reaction solution in a desired pH range during the complete reaction, a weak acid or a buffer acid or more bisulfite can be added to the reaction solution as needed. In another modality, the alkyl substituted hydroxyalkyl isethionates are prepared by making the bisulfite in situ by reacting a hydroxide solution, such as sodium hydroxide with sulfur dioxide, under pressure. The alkoxide can be added concurrently or later to produce the corresponding hydroxyalkyl isethionates and the alkyl substituted hydroxyalkyl isethionates. In addition, the temperature and the reaction pressure during the production of the alkyl substituted hydroxyalkyl isethionates may vary from about 50 ° C to about 200 ° C and from about 69 kPa (10 psi) to about 689 kPa (100 psi), respectively. The temperature and pressure of the reaction solution can be maintained constant throughout the reaction or either or both can be increased or decreased at any time for any period of time to produce the alkyl substituted hydroxyalkyl isethionate desired. In addition, the alkyl substituted hydroxyalkyl isethionates can be prepared as a liquid or solid form. For example, the alkyl substituted hydroxyalkyl isethionates can first be prepared in liquid form and then spray dried to a powder form. Thus, in one embodiment, the alkyl substituted hydroxyalkyl isethionates are prepared in liquid form by reacting propylene oxide or butylene oxide with sodium bisulfite. The liquid salts of the alkyl substituted hydroxyalkyl isethionate are then spray dried to their corresponding powder form. Alkyl-substituted hydroxyalkyl isethionate powders have been found to be less hygroscopic and therefore easier to handle than isethionate powders not substituted by alkyl making their transport more efficient and less expensive. In addition, the use of the alkyl substituted hydroxyalkyl isethionate powder allows removal of the water removal step that is normally required when a hydroxyalkyl isethionate substituted with alkyl, liquid, is used during direct esterification. The alkyl-substituted hydroxyalkyl isethionates can then be used as a raw material together with the carboxylic acids in the production of alkyl-substituted acylalkyl-ethionate esters of the present invention. The carboxylic acids used in producing the esters of the present invention have the general formula (III): R-COOH, wherein R is any hydrocarbon group having between about 4 and about 25 carbon atoms. The hydrocarbon group R may be saturated or unsaturated and may be straight or branched chain. Generally, an excess of carboxylic acid is used to produce the esters of the present invention. In this way, the amount of carboxylic acid used can vary from a molar ratio of carboxylic acid to hydroxyalkyl isethionate from 1.3: 1 to 1.1: 1, However, a proportion range can also be used, if desired. molar of carboxylic acid relative to hydroxyalkyl isethionate as large as 2: 1 or as low as 0.9: 1. Examples of suitable carboxylic acids for use in the present invention include: acid coconut; butyric acid; hexanoic acid; caproic acid; caprylic acid; capric acid; lauric acid; myristic acid; palmitic acid; palmitoleic acid; stearic acid; oleic acid; linoleic acid; arachidic acid; gadoleic acid; arachidonic acid; EPA; behinic acid; eruic acid; DHA; lignoceric acid; naturally occurring fatty acids such as coconut oil, tallow, palm kernel oil, shortening fat, palm oil, olive oil, corn oil, flaxseed oil, peanut oil, fish oil and rapeseed oil; synthetic fatty acids made as single-length chains or selected distribution of chain lengths; and mixtures of any of the foregoing. Those skilled in the art will appreciate that fatty acids obtained from sources as found in nature are mixtures of acids having various carbon chains of various lengths. Therefore, it is within the scope of this invention to use one or more fatty acids as found naturally (including mixtures thereof), synthetic fatty acids (including mixtures thereof) and mixtures of both natural and fatty acids. synthetic In addition, "acid coconut" or "fatty acid coconut", as used herein, is a commercial mixture of fatty acids containing a range of carboxylic acids having chain lengths of between about 8 and 18 carbon atoms, and some saturation which can be eliminated by hydrogenation. In this way, the hydrogenated acid coconut is a mixture of carboxylic acids having chain lengths of 8 to 18 carbon atoms, mainly lauric and myristic, together with some capric and caprylic acids and contains very little unsaturation, if any. To assist in the preparation of the alkyl-substituted acylalkyl-ethionate esters, an esterification catalyst may be used and may be combined with the alkyl-substituted hydroxyalkyl isethionate and the carboxylic acid. An appropriate esterification catalyst suitable for use includes alkylisethionic acids, salts of hydroxyalkane sulfonates, methanesulfonic acid, p-toluenesulfonic acid, inorganic acids such as sulfuric acid, phosphoric acid, phosphorous acid, boric acid or its anhydrides, heavy metal salts such such as zinc sulfate, zirconium sulfate, zinc isethionate, zinc citrate, zinc borate, aluminum sulfate, titanium sulfate or tungsten phosphate, metal oxide such as zinc oxide, aluminum oxide, magnesium oxide, cerium oxide, zirconium oxide or lanthanum oxide and also mixtures of two or more of these catalysts and soaps formed of heavy metals and metal oxides. The esterification catalyst can be used in an amount of 0.05 to 2% by weight, preferably 0.05 to 1% by weight, based on the total weight of the reactants. In one embodiment, the alkyl substituted acylalkyl isethionate ester is prepared using the acid form of the alkyl substituted hydroxyethane sulfonate as the esterification catalyst. The alkyl substituted isethionic hydroxyethane can be added in its pure form or a strong acid can be added to the carboxylic acid-containing reaction mixture and the alkyl substituted hydroxyethane isethionate salt to convert the isethionate salt to the acid form. The double use of the hydroxyethane sulfonate substituted with alkyl as both a reactant and with a catalyst is preferred since there is no need to suspend or remove the catalyst, there is no catalyst residue so that there is a minimum change in the molecular weight distribution of the acylalkyl-isethionate ester, so that the manufacturing capital expenditures are reduced and processing time decreases. The acylalkyl-isethionate esters according to the present invention produced from alkyl-substituted hydroxyalkyl isethionates are much more stable hydrolytically than the acylalkyl-isethionate esters produced from unsubstituted alkyl-hydroxyalkyl isethionates such as SCI. Currently, SCI users use a test to determine the hydrolytic stability of SCI by submitting it in aqueous solution of the SCI at an elevated temperature of 55 ° C for a period of time up to 30 days, during which the degree of hydrolysis of the SCI is determined. SCI. As shown in Figure 1, the present invention solves the hydrolysis problem. Figure 1 shows the hydrolytic stability of 10% aqueous solutions of SCI and acylmethylisethionate esters prepared from coconut fatty acids and methyl substituted isethionate (made by reacting propylene oxide and sodium bisulfite) and the acylethalylethionate esters prepared from coconut fatty acids and isethionate substituted with ethyl during a period of 30 days at a temperature of 56 ° C. We refer to the ester produced from coconut fatty acids and methyl substituted isethionate as "sodium cocoylmethyl isethionate" or "SCMI" in its abbreviated form. We refer to the ester produced from coconut acids and ethyl-substituted isethionate as "sodium cocoyl ethyl isethionate" or "SCEI". As shown in Figure 1, the SCI ester undergoes hydrolysis while both of the SCMI and SCEI esters are hydrolytically stable over the 30 day period.

In addition, the SCMI and SCEI ester is completely soluble when added to water and thus a clear 10% ester solution is formed. In comparison, the 10% SCI solution is cloudy and requires heating to solubilize the SCI in water. Thus, it has surprisingly been found that by replacing hydrogen with alkyl groups of 1 to 6 carbon atoms, one or both of the carbon atoms of the ethanesulfonate portion of an acylalkyl-isethionate ester, the hydrolytic stability and the water-solubility of the acylalkyl-isethionate ester they improve remarkably. That is, by providing a Cl to C6 on one or both carbon atoms of isethionic acid (or isethionate salt) in the raw material used to produce the acylethylethe thioate ester, the water solubility and hydrolytic stability of the modified ester are improved. This result is completely unexpected in view of the common knowledge in the art that increasing the hydrocarbon character in a material generally results in a reduction in its water solubility. As a result of this improved solubility and hydrolytic stability, the acylalkylisethionates of the present invention are suitable for use in liquid personal care cleaners and are not limited to bars of soap. In general detail, the esterification reaction can be carried out by charging the carboxylic acid, the alkyl substituted hydroxyalkyl isethionate optionally the esterification catalyst under atmospheric pressure or vacuum in a reaction vessel. The reaction vessel is perfectly purged with a dry inert gas, such as nitrogen. The direct esterification is carried out by heating the reaction mixture to the reaction temperature with stirring. Water can be introduced into the reaction mixture with the initial components and the water that is formed as a result of the esterification reaction is discharged from the reaction vessel. In addition, it may also be required to distill off some of the excess carboxylic acid during the development of the esterification reaction. The reaction time to complete the esterification will vary from 1 to 12 hours, depending on the reaction temperature and, if present, the amount of esterification catalyst. The final alkyl-substituted acylalkyl-isethionate ester product can then be supplied in liquid or solid form, such as a powder or a paste, for use as a raw material in the formulation for personal care cleaners. The esterification reaction can be carried out in a reaction vessel under atmospheric pressure. However, to assist in the removal of water, moderate vacuum (500-550 mm Hg) may be applied during the start of loading the reagents or at any time during the reaction. The application of moderate vacuum also allows the extraction of water without distilling the carboxylic acid. Preferably, the applied vacuum is not allowed to fall below 500 mm Hg so as to avoid the distillation of carboxylic acid when it is not desired. Generally, the reaction vessel is heated to a single reaction temperature range. However, the process can use more than one reaction temperature range. For example, the reaction vessel can be heated to a first reaction temperature range and can be maintained in said temperature range for a period of time to remove water, and then subsequently heated additionally to a second temperature range. greater than the first and is maintained for a period of time. The reaction temperature ranges used during the esterification reaction can vary from about 200 ° C to about 240 ° C. However, it has surprisingly been found that if alkyl-substituted hydroxyethylenic acid is used as the catalyst, the reaction temperature can be lowered to a temperature range of about 90 ° C to about 180 ° C., preferably from about 120 ° C to about 160 ° C. In one embodiment, the acylalkylcyanate ester is produced by combining one or more carboxylic acids and one or more sodium salts of the alkyl substituted hydroxyalkane isethionate with an alkyl substituted hydroxyethane isethionic acid catalyst in a reaction vessel. The reaction vessel is purged using nitrogen and the reaction mixture is heated to a first temperature range from about 120 ° C to about 130 ° C for 30 minutes to remove water from the reaction components. The reaction mixture is then subsequently heated to a range of about 140 ° C to about 150 ° C to initiate the esterification reaction. A moderate vacuum (500-550 mm Hg) is applied during the esterification reaction to aid in the separation of water and the reaction mixture is heated continuously until the separation by distillation of the water ceases. The vacuum can be adjusted during the reaction to prevent the carboxylic acid from being distilled off. After the esterification is complete, the substituted hydroxyethane isethionic acid with residual alkyl present as a catalyst can be neutralized with an alkaline substance to a caustic, amine, ammonia or substituted ammonium compound such as monoamines, diamines and triamines and alkanolamine such as ethanolamine. The excess fatty acid can be conveniently separated by vacuum distillation at temperatures and pressures ranging from 100 ° -250 ° C and 1-200 mm Hg to make a product substantially free of fatty acid. Once formed, the acylalkylcyanation esters can be used as a surfactant or as a surface active agent in a variety of personal care cleaners. Personal care cleaners include, but are not limited to: liquid soaps, shampoos, shower gels, bubble baths, combination bars of synthetic soap, acne rinses, anti-dandruff shampoos, make-up removers, body lotion rubbed facial, handkerchiefs for baby and handkerchiefs for children. In this manner, the compounds of the invention can be used in any cleansing composition for personal care as are known to those skilled in the art. The acylalkyl-isethionate esters of the present invention can be used in personal care cleaners as a primary surfactant at concentrations ranging from 1% to 60% by weight. In addition, the acylalkyl-isethionate esters of the present invention can be combined with other surfactants and materials which are used in personal care cleaners at concentrations of acylalkyl-isethionate ester ranging from up to about 60% by weight. To the extent that other surfactants are used in combination with the acylalkyl-isethionate esters of the present invention in the formation of binary active systems, triple active systems, etc., the acylalkyl-isethionate ester can comprise most of the surfactant system (if required more than one active substance) in which it is referred to as the primary surfactant, or it may comprise less than most of the active surface system in which it is referred to as a secondary surfactant. Other surfactants and materials which can be used in combination with the alkyl-substituted acylalkyl-ethionate esters for the formation of a personal care cleaner include amphoteric / zwitterionic surfactants; anionic surfactants; nonionic surfactants; cationic surfactants and optional ingredients. The amphoteric surfactants used in the present invention can be broadly described as u? surfactant which contains at least one anionic and one cationic group and which can act as either acids or bases, depending on the pH. Some of these compounds are aliphatic derivatives of heterocyclic secondary and tertiary amines in which the aliphatic radical can be linear or branched and wherein one of the aliphatic substituents contains from about 6 to about 20, preferably from 8 to 18, carbon atoms. and at least one contains an anionic solubilising group, for example carboxy, phosphonate, phosphate, sulfonate, sulfate. Zwitterionic surfactants can generally be described as surfactants having a positive and negative charge on the same molecule, which molecule is zwitterionic at all pH. Zwitterionic surfactants can be better illustrated by betaines and sultaines. Zwitterionic compounds generally contain a portion of quaternary ammonium, quaternary phosphonium or a tertiary sulfonium. The cationic atom in the quaternary compound can be part of a heterocyclic ring. In all of these compounds there is at least one aliphatic group, a straight or branched chain containing from about 6 to 20, preferably from 8 to 18 carbon atoms and at least one aliphatic substituent containing an anionic water-solubilizing group, example carboxy, sulfonate, sulfate, phosphate or phosphonate.

Examples of suitable amphoteric and zwitterionic surfactants include the alkali metal, alkaline earth metal, ammonium and substituted ammonium salts of alkyl amfocarboxiglycinates and alkyl amfocarboxipropionates, alkyl amodipropionates, alkyl monoacetate, alkyl diacetates, alkyl ammoglycinates and alkyl amopropropionates, wherein alkyl represents an alkyl group having from 6 to about 20 carbon atoms, other suitable surfactants include alkyliminomonoacetates, alkylmindialdetates, alkyliminopropionates, alkyliminidipropionates and alkylamphopropyl sulfonates having between 12 and 18 carbon atoms, alkylbetaines and alkylamidoalkylenebetaines and alkylsultaines and alkylamidoalkylenehydroxysulfonates. The anionic surfactants which may be used in the present invention are those surfactant compounds which contain a long chain hydrocarbon hydrophobic group in their molecular structure and a hydrophilic group, which includes salts such as carboxylate, sulfonate, sulfate or phosphate groups. The salts may be sodium, potassium, calcium, magnesium, barium, iron, ammonium and amine salts of such surfactants. The anionic surfactants include alkali metal, ammonium and alkanolammonium salts of organic sulfuric reaction products having in their molecular structure an alkyl or alkaryl group containing from 8 to 22 carbon atoms and a sulfonic acid or acid group. sulfuric. Examples of such anionic surfactants include water-soluble salts of alkylbenzene sulphonates having 8 to 22 carbon atoms in the alkyl group, alkyl ether sulfate having 8 to 22 carbon atoms in the alkyl group and 2 to 9 moles of oxide of ethylene in the ether group. Other anionic surfactants that may be mentioned include alkyl sulfosuccinates, alkyl sulfosuccinate ethers, olefin sulfonates, alkyl sarcosinates, alkyl monoglycerides sulfates and ether sulfates, alkyl carboxylate ether, paraffin sulfonates, mono and dialkyl phosphate esters and ethoxylated derivatives , acyl methyl taurates, fatty acid soaps, hydrosylated collagen derivatives, sulfoacetates, acyl lactates, aryloxide disulfonates, sulfosuccinamides, naphthalene formaldehyde condensates and the like. Aryl groups generally include one or two rings, alkyl generally includes from 8 to 22 carbon atoms and the ether group generally ranges from 1 to 9 moles of ethylene oxide (EO) or PO, preferably EO. Specific anionic surfactants which may be selected include linear alkylbenzene sulfonates such as decylbenzene sulfonate, undecylbenzene sulfonate, dodecylbenzene sulfonate, tridecylbenzene sulfonate, nonylbenzene sulfate and the sodium, potassium, ammonium, triethanolammonium and isopropylammonium salts of the same. Nonionic surfactants can also be used in combination with the alkyl-substituted acylalkyl-ethionate esters of the present invention. One or more of the nonionic surfactants is not critical and can be any of the known nonionic surfactants which are generally selected on the basis of compatibility, efficiency and economy. Examples of useful nonionic surfactants include condensates of ethylene oxide with a hydrophobic portion which has a hydrophilic-lipolytic balance (HLB) between about 8 and about 16, and preferably between about 10 and about 12.5. The surfactants include ethoxylated primary or secondary aliphatic alcohols having from about 8 to about 24 carbon atoms, either in the straight or branched chain configuration, with from about 2 to about 40, and preferably from about 2 to about 9. moles of ethylene oxide per mole of alcohol. Other suitable nonionic surfactants include the condensation products of alkylphenols with from about 6 to about 12 carbon atoms with from about 3 to about 30., and preferably between about 5 to about 14 moles of ethylene oxide. Many cationic surfactants are known in the art and almost any cationic surfactant having at least one long chain alkyl group of about 10 to 24 carbon atoms is suitable for optional use in the present invention. Other optional ingredients or additives which can be used in combination with the alkyl substituted acylalkyl-ethionate esters in the personal care cleanser formulation include pH-adjusting chemicals, for example, lower alkanolamines such as monoethanolamines (MEA) and triethanolamines. (TEA) Sodium hydroxide solutions can also be used as an agent to adjust the alkaline pH. Chemicals that adjust the pH work to neutralize acidic materials that may be present. Mixtures of more than one chemical that adjusts the pH can also be used.

Phase regulators (well known in liquid detergent technology) can also be optionally used in the present invention. These can be prepared by lower aliphatic alcohols having from 2 to 6 carbon atoms and from 1 to 3 hydroxyl groups, diethylene glycol ethers and lower aliphatic monoalcohols having from 1 to 4 carbon atoms and the like. Detergent hydrotropes can also be included. Examples of detergent hydrotropes include alkylaryl sulfonate salts having up to 3 carbon atoms in the alkyl group, for example sodium, potassium, ammonium and ethanolamine salts of xylene, toluene, ethylbenzene, eumeno and isopropylbenzenesulfonic acids. Other optional supplemental additives include defoamers such as high molecular weight aliphatic acids, especially saturated fatty acids and soaps derived therefrom, dyes and perfumes; fluorescent agents or optical brighteners; agents that prevent redeposition such as carboxymethylcellulose and hydroxypropylmethylcellulose; suspension stabilizing agents and soil release promoters such as copolymers of polyethylene terephthalate and polyoxyethylene terephthalate; antioxidants; softening agents and antistatic agents; photoactivators and conservatives; polyacids, sludge regulators, opacifiers, bactericides and the like. The slurry regulators can be illustrated by alkylated polysiloxanes and the opacifiers can be illustrated by polystyrene; the bactericide can be illustrated by butylated hydroxytoluene. Although not required, an inorganic or organic diluent may optionally be added in small amounts to the final composition. Examples of inorganic diluents include water-soluble alkali metal carbonates, bicarbonates, silicates and amorphous crystalline aluminosilicates. Examples of organic diluents include polyacetates, carboxylates, polycarboxylates, polyacetyl, carboxylates and polyhydroxysulfonates of alkali metal, metalalkaline, ammonium and substituted ammonium. An example of a commonly used diluent is sodium citrate. Optional ingredients and optional surfactants can be added to the alkyl substituted acylalkylcyanate ester prior to, during or after formulation of the personal care cleanser. In addition, combinations of the alkyl substituted acylalkylcyanate ester in combination with these ingredients and optional surfactants can be made directly for sale or for compounding to meet the needs of the user.

In this manner, the acylalkylcyanate esters of the present invention are useful in formulations which contain materials that are typically used and known to those skilled in the art and which are useful in formulating soap products, detergent products and other material-like products. cleaners, particularly, but not limited to cleaners for personal care. For purposes of this invention, the words "material known to those skilled in the art as useful in the formulation of soaps, detergents and the like" means one or more materials that are selected from the group consisting of: fatty acids, alkyl sulfates, ethanolamines , amine oxides, alkali carbonates, water, ethanol, isopropanol, pine oil, sodium chloride, sodium silicate, polymers, alcohol alkoxylates, zeolites, perborate salts, alkali sulfates, enzymes, hydrotropes, dyes, fragrances, preservatives, brighteners, thinners, polyacrylates, essential oils, alkali hydroxides, ether sulfates, alkylphenol ethoxylates, fatty acid amides, alpha-olefin sulphonates, paraffin sulfonates, betaines, chelating agents, tallowamine ethoxylates, polyetheramine ethoxylates, copolymers of ethylene oxide / propylene oxide block, low ethylene oxide / propylene oxide alcohol surfactant, methyl ester sulfonates, alkyl polysaccharides, N-methylglucamides, sulphonated and alkylated diphenyl oxide and alkylbenzene sulfonates or water-soluble alkyl toluene sulphonates, as well as the use thereof in the formulation of soaps, detergents and cleaners-like products as are known in the technique. In one embodiment, the acylalkyl-isethionate esters of the present invention may be present in facial and body cleansing compositions. These cleansing compositions may also comprise a fatty acid soap together with other surfactants that are not soaps such as mild synthetic surfactants. The body and facial cleansing compositions also generally include a humectant or emollient and auxiliaries for skin feel and polymeric smoothness. The compositions may optionally include thickeners (for example magnesium aluminum silicate, carbopol), conditioners, water-soluble polymers (for example carboxymethylcellulose), dyes, hydrotropes, brighteners, perfumes and germicides. In another embodiment, the acylalkyl-isethionate esters of the present invention may be present in a shampoo. The shampoo composition also comprises one or more additional surfactants, a compound considered useful for treating dandruff, such as selenium sulfide, an agent that improves the suspension, an amide, a non-ionic polymer material to aid in the dispersion of particles , a non-volatile silicone fluid and a variety of other non-essential components suitable for reverting to the more formulable composition, such as preservatives, viscosity modifiers, pH adjusting chemicals, perfumes and colorants. In a further embodiment, the acylalkylcyanation esters of the present invention may be present in a light duty liquid detergent composition. The lightweight liquid detergent composition may further include one or more additional surfactants, opacifiers (eg, ethylene glycol distearate), thickeners (eg, guar gum), antimicrobial agents, anti-tarnish agents, heavy metal chelators (e.g. EDTA). ), perfumes and dyes. In a further embodiment, the acylalkyl-isethionate ester of the present invention may be present in a heavy-duty liquid detergent composition. The heavy duty liquid detergent composition may also include one or more additional surfactants, an electrolyte (ie, a water-soluble salt), enzymes with or without stabilizers such as calcium ion, boric acid, propylene glycol and / or chain carboxylic acids. short and conventional alkaline detergency builders. In still another embodiment, the alkyl substituted acylalkyl-isethionate ester may be present in a conditioning composition comprising alkylamine compounds. In a different embodiment, the acylalkyl-isethionate esters of the present invention may be present in a cosmetic composition. The cosmetic composition may further include at least one polymeric thickening agent, one or more chemical preservatives or substances that depress water activity to prevent contamination by microbes, a sunscreen agent such as p-aminobenzoic acid, and a carrier. The carrier may include a diluent, dispersant or carrier useful to ensure a uniform distribution of the composition when applied to the skin and may include water, an emollient such as an alcohol or oil, a propellant, for example trichloromethane, carbon dioxide or nitrous oxide, a humectant and a powder such as chalk, talc and starch. The advantages of the alkyl-substituted acylalkyl-ethionate esters of the present invention with respect to traditional surfactants include: (1) a high water-solubility of the alkyl-substituted acylalkyl-ethionate esters which allows the esters to be used alone in aqueous cleaners for the personal care or other detergent solutions so that they do not require the addition of other expensive cosurfactants that are used for solubilization of other acylalkyl-isethionate esters such as SCI; (2) the alkyl-substituted acylalkyl-ethionate esters are hydrolytically stable in aqueous solutions due to the secondary alcohol ester structure; (3) Due to their non-irritant properties, alkyl-substituted acylalkyl-ethionate esters can be used as a primary surfactant instead of traditional anionic surfactants such as [sodium lauryl sulfate and sodium lauryl ether sulfate] in care cleaners personal; (4) dioxane 1: 4 is not produced nor is it present during the preparation of the alkyl-substituted acylalkyl-ethionate esters; and (5) "sulfate-free" personal care cleaners can be made using the alkyl-substituted acylalkyl-ethionate esters without the addition of taurates and sarcosinates necessary to remove sulfates in current personal care cleaners.

The examples that follow now should be considered as exemplary of the present invention and not as limiting thereof, in any way.

EXAMPLE 1 Preparation of sodium methyl isethionate A stainless steel autoclave reactor-316 of 11.4 1 (3 gallons) is charged with 4.3 kg (9.40 pounds) of a 35% aqueous solution of sodium bisulfite having a pH of 6.5 -7.0 and then purged with nitrogen to expel the air. The reactor is then heated to approximately 70 ° C and 0.45 kg is added (1.0 lb.) of propylene oxide to the reactor, at a pressure of 414 kPa (60 p.s.i.). The reagents are allowed to react for about 30 minutes at a temperature of about 80 ° C, after which time the pressure in the reactor decreases to about 6.9 kPa (1 p.s.i.). The reaction is allowed to continue for 60 minutes at 80 ° C, then cooled to 50 ° C and the product solution is separated from the reactor and analyzed. The analysis shows that the product solution has a pH of 13.50, < 0.50% by weight of propylene glycol and both isomers are present, both the 2-methyl 2-hydroxyethane-1-sulfonate and the 2-hydroxyethane-1-sulfonate 1-methyl.

A second stainless steel autoclave reactor -316 of 11.4 1 (3 gallons) is loaded with 4.4 kg (9.69 pounds) of a 35% aqueous solution of sodium bisulfite having a pH of 6.5-7.0 and then purged with nitrogen to exclude air. The reactor is heated to about 70 ° C and 0.68 kg (1.5 pounds) of propylene oxide is added to the reaction at a pressure of 414 kPa (60 p.s.i.). The reagents are allowed to react at 80 ° C for 30 minutes, after which time the pressure decreases to about 6.9 kPa (1 p.s.i.). The reaction is allowed to continue for 60 minutes at a temperature of 95 ° C, then cooled to 50 ° C and the product solution is separated from the reactor and analyzed. The analysis shows that the product solution has a pH of 14.00, approximately 3.0% by weight of propylene glycol and both isomers, 2-methyl 2-hydroxyethane-1-sulfonate and 2-hydroxyethane-1-sulfonate are present. -methyl. In a stainless steel reactor -316 of 644 1 (170 gallons) equipped with a stirrer, a nitrogen line, an oxide line, a temperature probe and a pH probe is loaded with 136 kg (300 pounds) of water DI and 54.4 kg (120 pounds) of a 50% caustic solution.

The reactor is pressurized with nitrogen three times (276-0 kPa (40-0 psi) .S02 is then passed through the reactor and the solution with stirring at a pH of 7.0-7.50, then the reactor is heated to about 70 ° -75 ° C and added to the propylene oxide reactor at a rate of 0.23 kg / min (0.50 pounds / minute) The pH is controlled during the reaction by the addition of small injections of S02 In addition, the addition of PO towards the end of the reaction is decreased to maintain good pH control Reagents are allowed to digest at 95 ° C for 4 hours A total of 42.2 kg (93 pounds) of S02 and 40.8 kg (90 pounds) of propylene oxide are used throughout the reaction. Then the reactor is opened to let out the fumes in an extraction hood and any unprocessed propylene oxide is cleaned off with a nitrogen purge for one hour.The reaction mixture is cooled to room temperature and discharge into drums, the clear and colorless product analyzed and the results show: 0.50% by weight of propylene glycol and 50.20% by weight of sodium methylisethionate (both isomers are present, 2-methyl 2-hydroxyethane-1-sulfonate and 1-methyl 2-hydroxyethane-1-sulfonate ).

EXAMPLE 2 Preparation of sodium ethyl isethionate A stainless steel autoclave reactor -316 of 11.4 1 (3 gallons) is charged with 4.4 kg (9.69 pounds) of a 35% aqueous solution of sodium bisulfite having a pH of 6.5-7.0 , and then purged with nitrogen to expel the air. The reactor is then heated to about 70 ° C and 1.2 kg (2.6 pounds) of butylene oxide are added to the reactor at a pressure of 414 kPa (60 p.s.i.). The reagents are allowed to react for about 30 minutes at a temperature of about 80 ° C, time after which the pressure in the reactor decreases to approximately 6.9 kPa (1 p.s.i.). The reaction is allowed to continue for 60 minutes at 95 ° C and then cooled to 50 ° C and the product solution is separated from the reactor. By allowing to cool, bright crystalline plates are separated from the product solution which requires water to be added to dissolve the solids in solution again. The product solution is then analyzed and analysis shows that the product solution has a pH of 14.00, about 3.0% by weight of butylene glycol and both 2-hydroxyethane-1-sulfonate isomers of 2-ethyl and 2-hydroxyethane are present. 1-ethyl 1-sulfonate. A second stainless steel autoclave reactor -316 of 11.4 1 (3 gallons) is charged with 4.4 kg (9.69 pounds) of a 35% aqueous solution of sodium bisulfite having a pH of 5.0-5.5 and then purged with nitrogen to expel the air. The reactor is heated to about 70 ° C and 1.2 kg (2.6 pounds) of butylene oxide is added to the reaction at a pressure of 414 kPa (60 p.s.i.). The reagents are allowed to react at 80 ° C for 30 minutes, after which time the pressure decreases to about 6.9 kPa (1 p.s.i.). The reaction is allowed to continue for 60 minutes at a temperature of 95 ° C, then cooled to 50 ° C and the product solution is separated from the reactor. After allowing to cool, bright crystalline plates are separated from the product solution, which requires water to be added to dissolve the solids in the solution again. The product solution is then analyzed and the analysis shows that the product solution has a pH of 14.00, approximately 13.0% by weight of butylene glycol and both isomers are present, 2-ethyl 2-hydroxyethane-1-sulfonate and 2- 1-ethyl hydroxyethane-1-sulfonate.

EXAMPLE 3 Preparation of sodium cocoyl ester (from 8 to 18 carbon atoms) methyl stionateate A laboratory reactor (500 ml round bottom flask equipped with mechanical stirrer, addition funnel, condenser, thermocouple and gas purge supply) it is initially charged with 212 grams (0.98 moles) of carboxylic acid (coconut hydrogenated acid C-110, P &G Chemicals, Cincinnati, Ohio). A total of 165 grams (1.0 moles) of sodium methyl isethionate containing a mixture of the 2-methyl-2-hydroxyethane-2-methyl-2-hydroxyethane-2-hydroxyethane-1-sulfonate sodium salts is also added to the reactor. methyl. 5.00 grams of the corresponding zinc methyl isethionate is added as a catalyst, in the same proportions of isomer as in the above. The purge reactor perfectly with dry nitrogen and is heated at 120 ° -130 ° C for 30 minutes to remove the water of the sodium methyl isethionate substituted with alkyl. The temperature of the reactor contents is then increased to 200 ° C for 6 hours, after which the excess of fatty acid is removed by low distillation at 10 mm Hg to acceptable concentrations of fatty acid (<10%) and the mixture of product contains 80% by weight of the corresponding esters suitable for combination in a personal care cleansing composition. In a secondary laboratory reactor (500 ml round bottom flask equipped with a mechanical stirrer, addition funnel, condenser, thermocouple and gas purge supply) 131.5 grams are added (0.625 moles) of a carboxylic acid (coconut fatty acid) C-110, P &G Chemicals, Cincinnati, Ohio), a total of 82.5 grams (0.5 moles solids) of sodium methyl isethionate containing a mixture of sodium salts of 2-methyl-2-hydroxyethane-2-sulfonate and 1-methyl 2-hydroxyethane-1-sulfonate and 2.2 grams of zinc citrate as a catalyst. The purge reactor perfectly with dry nitrogen and the solution is heated at 220 ° C for 6 hours, time after which the excess of fatty acid is removed by distillation under vacuum at 10 mm Hg to acceptable concentrations of fatty acid (< %) and the product solution is cooled to 160 ° C-170 ° C. The product solution is separated from the reactor and analyzed and the results show a product containing 81.5% by weight of the corresponding esters suitable for combination in a personal care cleansing composition, 12.0% by weight of carboxylic acid and 3.9% by weight of sodium methylisethionate that was not reacted.

EXAMPLE 4 Preparation of capriloyl sodium / methyl isethionate caproyl ester (8 to 10 carbon atoms) In a laboratory reactor (500 ml round bottom flask equipped with mechanical stirrer, addition funnel, condenser, thermocouple and purge supply) with gas) are charged 118 grams (0.75 moles) of carboxylic acid (C-810 fatty acid, P &G Chemicals, Cincinnati, Ohio) and a total of 82 grams (0.5 moles solids) of sodium methyl isethionate is added to the reactor containing a mixture of sodium salts of 2-hydroxyethane-1. 2-methyl sulfonate and 1-methyl 2-hydroxyethane-1-sulfonate. 2.2 grams of zinc citrate are added to the mixture as a catalyst. The purge reactor perfectly with dry nitrogen and the reagents are heated to 220 ° C for 6 hours, after which the product is cooled to 160 ° C - 170 ° C. The product solution is separated from the reactor and analyzed and the results show a solid bank having a saponification value of 186, active by titration in two phases of 2.54 meq / g and containing 86.7% by weight of the corresponding corresponding esters for combination in a personal care cleansing composition, 6.7% by weight of unreacted carboxylic acid and 6.5% by weight of unreacted sodium methylisethionate.

EXAMPLE 5 Preparation of Caproyl (of 10 carbon atoms) Methyl isethionate sodium ester In a laboratory reactor (500 ml round bottom flask equipped with mechanical stirrer, addition funnel, condenser, thermocouple and gas purge supply) are charged 108 grams (0.625 moles) of carboxylic acid (fatty acid C-1095, P & amp;G Chemicals, Cincinnati, Ohio) and a total of 82.5 grams (0.5 moles of solids) of sodium methyl isethionate is added to the reactor containing a mixture of 2-methyl 2-hydroxyethane-1-sulfonate sodium salts and 1-methyl 2-hydroxyethane-1-sulfonate. 1.9 grams of zinc citrate are added to the mixture, as a catalyst. The purge reactor perfectly with dry nitrogen and the reactants are heated to 220 ° C for 6 hours, after which the product is cooled to 160 ° C -170 ° C. The product solution is separated from the reactor and analyzed and the resulting white solid contains 82.5% by weight of the corresponding ester suitable for combination in a personal care cleansing composition, 7.7% by weight of unreacted carboxylic acid and 7.4% by weight. Weight of sodium methylisethionate that has not reacted.

EXAMPLE 6 Preparation of Lauroyl (of 12 carbon atoms) Methyl isethionate sodium ester In a laboratory reactor (500 ml round bottom flask equipped with mechanical stirrer, addition funnel, condenser, thermocouple and gas purge supply) are charged 125 grams (0.625 moles) of carboxylic acid (C1299 fatty acid, P &G Chemicals, Cincinnati, Ohio) and a total of 83 grams (0.5 moles of solids) of sodium methylisethionate containing a mixture of salts are added to the reactor. Sodium 2-methyl-2-hydroxyethane-1-sulfonate and 1-methyl 2-hydroxyethane-1-sulfonate. 2.2 grams of zinc citrate are added to the mixture as a catalyst. The purge reactor carefully with dry nitrogen and the reagents are heated to 220 ° C for 6 hours, after which the product solution is cooled to 160 ° C -170 ° C. The resulting white solid is separated from the reactor and analyzed and the results show a product containing 82.0% by weight of the corresponding ester suitable for combining in a personal care cleansing composition, 15.6% by weight of unreacted carboxylic acid and 3.9% by weight. % by weight of sodium methylisethionate which has not reacted.

EXAMPLE 7 Preparation of cocoyl (12 to 18 carbon atoms) sodium methyl sethionate ester In a laboratory reactor (500 ml round bottom flask equipped with mechanical stirrer, addition funnel, condenser, thermocouple and gas purge supply) 137.5 grams (0.625 moles) of carboxylic acid are charged (Emery 627 fatty acid, Henkel Corp. Emery Group, Cincinnati, Ohio) and a total of 85 grams (0.5 moles of solids) of sodium methylisethionate are added to the reactor (95 % by weight) containing a mixture of sodium salts of 2-methyl-2-hydroxyethane-1-sulfonate and 2-hydroxyethane-1-sulfonate of 1-methyl. 1.2 grams of zinc citrate are added to the mixture, as a catalyst. The purge reactor perfectly with dry nitrogen and the reactants are heated at 220 ° C for 6 hours, after which time the product solution is cooled to 160 ° C -170 ° C. The white solid is separated from the reactor and analyzed and the results show a product containing 82.2% by weight of the corresponding esters suitable for combination in a personal care cleansing composition, and 7.9% by weight of unreacted carboxylic acid.

EXAMPLE 8 Foaming Tests The foaming tests are carried out using a one-liter rotating measuring cylinder with lid of a foaming machine at a speed of 30 revolutions per minute and room temperature, ranging from approximately 20 ° C to approximately 22 ° C and at a concentration of 0.5% of the total surfactants. The foam heights are measured in the graduated cylinder at the beginning and after 10 minutes of rotation. The results are shown below in table I: TABLE I * Cocoamidopropyl betaine (EMPIGEN® BS / FA) ** EMPICOL®ESA *** SCMI produced from coconut fatty acid with 8 to 18 carbon atoms Sample 1 is an example of a commercial product that has one of the levels of the highest foam start in the personal care industry and is used as an internal standard through these tests. The results of this foam test show that SCMI foaming of 8 to 18 carbon atoms alone is not as good as that of SLES alone, but still shows synergy with CAPB betaine. This synergy is similar to other anionic surfactants, as shown by the results for sample 5 when 20% by weight of SCMI is replaced with CAPB. In this way, SCMI can be used with other surfactants and still maintain excellent foaming properties. The SCMI also shows a consistently tighter and creamier foam since it has a smaller bubble size compared to SLES in this type of formulations. A second foaming test is performed using the same parameters as above but with a purified coconut fatty acid SCMI chain that is tested instead of the SCMI full fatty acid chain. The results of this test are shown in Table II: TABLE II * Cocoamidopropyl betaine (EMPIGEN® BS / FA) ** SCMI produced from coconut fatty acid depurated from 12 to 18 carbon atoms Again, the results of this foam test show that foaming can be significantly increased when feeds purified SCMI coconut fatty acid instead of complete coconut. The height of SCMI scrubbing foam of 12 to 18 carbon atoms as well as the stability at 10 minutes are better than SLES alone and are similar to SLES / betaine performance. Besides, the SCMI from 12 to 18 carbon atoms again synergistic with CAPB, as shown by the results for samples 4 and 5 when 25% and 18% by weight of SCMI are replaced with CAPB. Therefore, SCMI can be used with other surfactants and still maintain or improve the excellent foaming properties. Finally, as shown in Figures 2A and 2B, the appearance of the SCMI foam is tighter and creamier than cleaners based on SLES or SLS which makes the use of SCMI highly desirable personal care cleaners. All samples shown in Figures 2A and 2B are 0.5% active surfactant.

EXAMPLE 9 Scoring of Zein irritation To assess the softness of the products of the present invention, the Zein ratings for a variety of sulfate and isethionate surfactants are determined and their ratings are reported in Table III: TABLE III From these in vitro results, the methyl and ethyl isethionates of the present invention are expected to be less irritating and therefore milder in comparison with sodium cocoyl isethionate which has been reported in the literature to be a non-irritating The skin and irritant of the eyes at concentrations of 10% by weight.

EXAMPLE 10 'Use of Sodium Cocoylmethylisethionate as a primary surfactant in high foaming personal cleaners An SCMI concentrate can be produced by directly adding molten SCMI produced, as in Example 3, into a solution of water and betaines (for example EMPIGEN ^ BS / FA, Huntsman Corporation, Austin, Texas). If the SCMI is in the form of powder or flake, the SCMI concentrate can be formed by dissolving SCMI powder or flakes in a solution containing cold water and betaines. The SCMI concentrate that is formed is a white pearled solution that has a viscosity that varies between 3000-5000 cps. The SCMI concentrate is easy to handle and its physical properties are similar to sodium laureth sulfate (eg EMPICOLMR, Huntsman Corporation, Austin, Texas) allowing its use in existing manufacturing facilities without the need for equipment improvement. As shown in Table IV, the SCMI concentrate can be formulated as follows: TABLE IV - SCMI concentrate formulation * EMPIGENMR BS / FA The SCMI concentrate can be used in the formulation of a variety of personal care cleaners, as shown in tables V to XI.

TABLE V - Formulation of a simple economic shampoo * EMPIGENMR BS / FA ** EMPIC0L M "R? ESB TABLE VI - Formulation of shampoo with little irritation * EMPIGEN M'iRK CDL60P TABLE VII - Shampoo formula for babies * EMPIREN TMRK CDL60P TABLE VIII - Luxurious formulation of liquid soap * EMPIGENMR CDL60P ** EMPIGENMR BS / FA TABLE IX - Economical formulation of liquid soap * EMPIGEN TM'1RK NHSSA ** EMPIGENR BS / FA TABLE X - Formulation of shower gel * EMPICOL • M1, R? ESB70 ** EMPIGENMR BS / FA TABLE XI - Concentrated shower gel formulation * EMPICOLMR ESB70 ** EMPIGENMR BS / FA All the formulations elaborated in the above using SCMI as the primary surfactant form a clear solution that is hydrolytically stable when stored. In comparison, when SCMI is substituted with SCI as the primary surfactant, the formulations are cloudy and separate when stored. Therefore, the use of SCMI as a primary surfactant in personal care cleaners is desirable since it is highly soluble, hydrolytically stable and mild to the skin. EXAMPLE 11 Solubility in Taurate To determine the solubility of SCI, SCMI and SCEI in taurate, three solutions are prepared at room temperature. The solutions are each formulated with one of SCI, SCMI and SCEI, and each contains the following ingredients, as shown in Table XII: TABLE XII - Solubility in Taurate * EMPIGEN • M11RK CDL60P As shown in figure 3, before the formulation, the solution of SCMI (solution 2) and the solution of SCEI (solution 3) produce a clear crystalline solution and therefore are completely soluble. In addition, the SCMI and SCEI solutions do not separate when they are stored. In comparison, the SCI solution (solution 1) forms a cloudy and milky solution that is subsequently separated during storage. Consideration should be given to the fact that although the invention has been described and presented in relation to some preferred embodiments, equivalents and modifications as well as obvious alterations thereof to the reading and compression of this specification will be evident to a person usually skilled in this technique. and the appended claims thereto. The present disclosure includes subject matter defined by any combination of any of the various claims appended thereto to any one or more of the remaining claims, which include incorporation of the features and / or limitations of any dependent claim, alone or in combination with features and / or limitations of any one or more other dependent claims having characteristics or limitations of any one or more of the independent claims with the dependent claims remaining in their text originate that they must be read and applied to any modified independent claim in this way. This also includes the combination of the characteristics or limitations of one or more independent claims with the characteristics or limitations of another independent claim to arrive at a modified independent claim where the dependent claims remaining in their original text must be read and applied to any claim independent modified in this way. Accordingly, the presently described invention is intended to cover all such modifications and alterations and is limited only by the scope of the claims that follow, in view of the foregoing and other contents of this specification. Through this specification, various percentages have been established and these percentages always refer to percent by weight, unless it is established in another sense.

Claims (23)

1. A method useful for forming a composition of aqueous material comprising a mixture of alkyl substituted hydroxyethansulfonates, comprising the steps of: a) providing at least one alkylene oxide having between 3 and 8 carbon atoms per molecule; b) providing an aqueous solution comprising bisulfite anions; c) contacting the aqueous solution with the alkylene oxide and at the same time maintaining the pH in a range between about 6.0 and about 10.0, wherein the mixture of alkyl substituted hydroxyethane sulfonates comprises: (i) a first anion that has the structure: wherein one of Ri and R2 is an alkyl group of 1 to 6 carbon atoms straight or branched chain and the remainder of Ri and R2 is hydrogen; and (ii) a second anion having the structure: 3R4 HO-CHCH S03 ~ wherein one of R3 and R4 is an alkyl group of 1 to 6 carbon atoms straight or branched chain and the remaining R3 and R4 is hydrogen.

2. Process as described in claim 1, wherein the aqueous solution of bisulfite ions further includes at least one ion selected from the group consisting of: sodium, potassium, lithium, magnesium, calcium and ammonium ions.

3. Process as described in claim 1, wherein the contacting is carried out at a temperature range of between about 20 ° C and about 200 ° C.

4. Process as described in claim 1, wherein the contacting is carried out in a pressure range of between about 0.5 atmospheres and about 7 atmospheres.

5. A process useful for forming an aqueous material composition, comprising a mixture of alkyl substituted hydroxyethyl sulfonates, comprising the steps of: a) providing at least one alkylene oxide having between 3 and 8 carbon atoms per molecule; b) providing an aqueous solution comprising bisulfite anions wherein the bisulfite anions are produced by reacting sulfur dioxide with a hydroxide solution; c) contacting the aqueous solution with the alkylene oxide and at the same time maintaining the pH in a range between about 7.0 and about 8.0, wherein the mixture of alkyl substituted hydroxyethyl sulfonates comprises: (i) a first anion having the structure: wherein one of Rx and R2 is an alkyl group of 1 to 6 carbon atoms straight or branched chain and the rest of Rx and R2 is hydrogen; and (ii) a second anion that 0 has the structure: HO-C IHCIH S03 wherein one of R3 and R is an alkyl group of 1 to 6 carbon atoms straight or branched chain and the remainder of R3 and R4 is hydrogen.

6. Process as described in claim 5, wherein the hydroxide solution is a 50% by weight sodium hydroxide solution.

7. A process for forming a composition of aqueous material comprising a mixture of alkyl substituted hydroxyethansulfonates, comprising the steps of: a) providing an alkylene oxide selected from the group consisting of: propylene oxide and sodium oxide; butylene and mixtures of the same; b) provide an aqueous solution of bisulfite anions; c) contacting the aqueous solution with the alkylene oxide while maintaining the pH in a range between about 6.0 and 10.0, wherein the mixture of alkyl substituted hydroxyethyl sulfonates comprises: (i) a first anion having the structure: and (ii) a second anion having the structure: R3R4 HO-C IHCIH S03 wherein Rr is independently selected from the group consisting of: methyl and ethyl; R2 is hydrogen; R3 is hydrogen and R4 is independently selected from the group consisting of: methyl and ethyl.

8. Process for forming a powder comprising a mixture of sodium alkyl substituted hydroethanesulfonates, comprising the steps of: a) providing an alkylene oxide selected from the group consisting of: propylene oxide and butylene oxide and mixtures thereof; b) provide an aqueous solution of sodium bisulfite; c) contacting the aqueous solution of sodium bisulfite with the alkylene oxide while maintaining the pH in a range of between about 6.0 and 10.0 for about 1 to about 6 hours to form a product mixture; and d) drying the product mixture to a powder, wherein the mixture of alkyl substituted hydroxyethyl sulfonates, comprises: (i) a first hydroxyethanesulfonate substituted with sodium alkyl, having the structure: and (ii) a second hydroxyethanesulfonate substituted with sodium alkyl having the structure: wherein Ri is independently selected from the group consisting of: methyl and ethyl; R2 is hydrogen; R3 is hydrogen and R4 is independently selected from the group consisting of: methyl and ethyl.

9. Aqueous material composition comprising a first anion having the structure: R1R2 HO-CHCH S03 wherein one of Rj and R2 is an alkyl group of 1 to 6 carbon atoms straight or branched chain and the Rx and R2 is hydrogen; and a different second anion that has the structure: R3 R HO-CHCH S03" wherein one of R3 and R4 is an alkyl group of 1 to 6 straight or branched chain carbon atoms and the remaining R3 and R4 is hydrogen.

10. Composition as described in claim 9, wherein the alkyl group of 1 to 6 carbon atoms in the first anion is the same as the alkyl group of 1 to 6 carbon atoms in the second anion.

11. Composition as described in claim 9, wherein the water is present in an amount between about 20% and about 90% by weight, based on the total weight of the composition.

12. Aqueous matter composition, comprising: (i) a first anion having the structure: and (ii) a second anion having the structure: R3 R HO-C IHCIH S03 wherein Ri is independently selected from the group consisting of: methyl and ethyl; R2 is hydrogen; R3 is hydrogen and R4 is independently selected from the group consisting of: methyl and ethyl.

13. Process for producing a surfactant material useful as a component for a personal care cleansing composition, which comprises: a) providing a mixture of isethionate anions which comprises a first anion having the structure: wherein R x is an alkyl group of 1 to 6 carbon atoms straight or branched chain, and R 2 is hydrogen; and (ii) a second anion having the structure: R3 R HO-C IHCIH S03 wherein R3 is hydrogen and R is an alkyl group of 1 to 6 carbon atoms straight or branched chain; b) contacting the isethionate anion mixture with one or more carboxylic acids of the formula: wherein R is any hydrocarbon group having between about 4 and about 25 carbon atoms, including straight chain, branched, saturated and unsaturated hydrocarbon groups so as to form a reactive mixture; and c) heating the reaction mixture at any temperature in the range of between 90 ° C and 240 ° C to produce a mixture of acyl alkyl isethionate containing at least two different anions which are esters of isethionate of a carboxylic acid.

The process as described in claim 13, further comprising the step of applying vacuum from about 1 mm to about 200 mm Hg at a temperature from about 100 ° C to about 200 ° C to reduce the amount of carboxylic acid in the surfactant material less than 10% by weight.

15. An ester anion mixture having surfactant properties useful in the formulation of personal care cleansing products, comprising: a) a first ester anion having the structure: R-? R-2 R-COO-CHCH S03- and b) a second ester anion having the structure: R3 4 R-COO-C IHCIH SO3- in which R, each time it occurs, is a hydrocarbon group having between about 4 and about 25 carbon atoms, which includes straight chain, branched, saturated and unsaturated hydrocarbon groups; one of R and R2 is an alkyl group selected from the group consisting of alkyl of 1 to 6 carbon atoms, and the rest of the groups Rx or R2, which are not alkyl of 1 to 6 carbon atoms, are hydrogen; one of R3 and R is an alkyl group selected from the group consisting of: alkyl of 1 to 6 carbon atoms and the remaining group R3 or R4, which are not alkyl of 1 to 6 carbon atoms, are hydrogen.

16. An ester anion mixture having surfactant properties useful in the formulation of cleaning products, which comprises: a) a first ester anion having the structure: R-? R-2 R-COO-CHCH S03- and b) a second different ester anion having the structure: R-3 R R-COO-CHCH SOf wherein R is any hydrocarbon group having between about 4 and about 25 carbon atoms, including straight chain, branched, saturated and unsaturated hydrocarbon groups; Rx is independently selected from the group consisting of: methyl and ethyl; R2 is hydrogen; R3 is hydrogen and R4 is independently selected from the group consisting of: methyl and ethyl.

17. Composition of useful material as a concentrate from which cleaning products can be prepared, comprising: a) one or more ester anions of an alkyliseethic acid, according to the formula: R *? Ro R -COO-C IHCIH S03- wherein R is a hydrocarbon group having between about 4 and about 25 carbon atoms, including straight chain, branched, saturated and unsaturated hydrocarbon groups; Ri and R2 can each be independently hydrogen or an alkyl group selected from the group consisting of alkyl of 1 to 6 carbon atoms subject to the proviso that both of x and R2 are not simultaneously hydrogen; and b) at least one member is selected from the group consisting of: water, a surfactant and an optional gradient used in preparing the cleaning product.

18. Composition of material from which cleaning products for personal care can be prepared, which comprises: a) any amount between 99.50% and 0.25% of a first component which comprises one or more ester anions of an alkyliseethic acid, according to the formula: Ri R2 R-COO-CIHCIH S03- in which R is any hydrocarbon group having between about 4 and about 25 carbon atoms, including straight chain, branched, saturated and unsaturated hydrocarbon groups; Rx and R2 each independently may be hydrogen or an alkyl group selected from the group consisting of: alkyl of 1 to 6 carbon atoms subject to the proviso that both Ri and R2 are not simultaneously hydrogen; and b) any amount between 99.75 and 0.50% of a second component comprising one or more members that are selected from the group consisting of: fatty acids, alkyl sulfates, an ethanolamine, an amine oxide, alkali carbonates, water, ethanol, isopropanol, pine oil, sodium chloride, sodium silicate, polymers, alcohol alkoxylates, zeolites, perborate salts, alkali sulfates, enzymes, hydrotropes, dyes, fragrances, preservatives, brighteners, builders, polyacrylates, essential oils, alkaline hydroxides, water-soluble branched alkylbenzene sulphonates, ether sulfates, alkylphenol alkoxylates, fatty acid amides, alphadefine sulfonates, paraffin sulfonates, betaines, chelating agents, tallowamine ethoxylates, polyetheramine ethoxylates, block copolymers of ethylene oxide / propylene oxide, low alcohol ethylene oxide / propylene oxide alcohol surfactant, methyl sulfonates ster, alkyl polysaccharides, N-methyl glucamides, sulfonated diphenyl oxide and alkylated and polyethylene glycol.

19. A personal care cleanser comprising an acylalkyl isethionate ester having the formula: wherein R is any hydrocarbon group having between 4 and 25 carbon atoms; Rx and R2 are each independently selected from the group consisting of hydrogen and an alkyl group of 1 to 6 branched carbon atoms or linear aliphatic which is subject to the proviso that only one of Rx and R2 is an alkyl group of 1. to 6 straight or branched aliphatic carbon atoms while the rest of Rx or R2 is hydrogen; and X is selected from the group consisting of hydrogen, an alkali metal, an alkaline earth metal, zinc, aluminum, ammonium and ammonium ions substituted with one or more organic groups.

20. A personal care cleanser, as described in claim 19, further comprising at least one member selected from the group consisting of: amphoteric surfactant; zwitterionic surfactant; anionic surfactant; nonionic surfactant; cationic surfactant; water and optional ingredients.

21. Composition of matter, comprising: (i) an acylalkyl-isethionate ester having the formula: wherein R is a hydrocarbon group having between 4 and 25 carbon atoms; Rx and R2 are each independently selected from the group consisting of hydrogen and an alkyl group of 1 to 6 branched carbon atoms or linear aliphatic subject to the proviso that one of Rx and R2 is the alkyl group of 1 to 6 atoms of linear or branched aliphatic carbon while the rest of R or R2 is hydrogen; and X is selected from the group consisting of hydrogen, an alkali metal, an alkaline earth metal, zinc, aluminum, ammonium and ammonium ions substituted with one or more organic groups and (ii) at least one member is selected from the group consisting of : Amphoteric surfactant; zwitterionic surfactant; anionic surfactant; nonionic surfactant; cationic surfactant; water and optional ingredients.

22. Composition of matter as described in claim 21, wherein the acylalkyl isethionate ester is present in an amount ranging from about 1% by weight to about 60% by weight.

23. Composition of matter as described in claim 21, wherein the composition of matter is a shampoo, baby shampoo, a baby towel, a children's towel, a makeup remover tissue, a shower gel, a bath of foam, a liquid soap, a bar of soap, a bar of synthetic detergent or an acne rinse.