USOO8008239B2 (12) United States Patent (10) Patent No.: US 8,008,239 B2 Anantaneni et al. (45) Date of Patent: Aug. 30, 2011 (54) ACYLALKYLISETHIONATE ESTERS AND (52) U.S. Cl. ........ 510/127:510/130,510/424:510/426; APPLICATIONS IN CONSUMER PRODUCTS 510/428; 554/92:554/149 (75) Inventors: Prakasa R. Anantaneni, Austin, TX (58) Field Elisatist Researchison None (US); John Gray, Round Rock, OH pp p ry. (US);X (US), Marty George J. Renner, A. Smith, Round Austin Rock, fix () References Cited (US);Donald David H. Champion, C. Lewis, Austin,Pflugerville, TX (US); TX U.S. PATENT DOCUMENTS (US); Christopher J. Whewell 1916,776 A 7, 1933 Steindorff et al. Georgetown,s TX (US) s 2,806,044.2,093,576 A 9/19579/1937 WeilSegessemann et al. (73) Assignee: Huntsman Petrochemical LLC. The 58. A E. Sto s al Woodlands, TX (US) 2.923,724. A 2, 1960 Anderson et al. 3,320,292 A 5, 1967 Cahn et al. (*) Notice: Subject to any disclaimer, the term of this 5,384,421 A 1/1995 Day et al. patent is extended or adjusted under 35 d ; A ck 3. 3: NE '' 554f149 U.S.C. 154(b) by 1298 days. 5,683,970- 4 - A 1 1/1997 Subramanyamelpy et al. et al. (21) Appl. No.: 10/S86027 6,069,262 A 5, 2000 Walele et al. y x- - - 9 FOREIGN PATENT DOCUMENTS (22) PCT Filed: Aug. 11, 2004 DE 1234 708 2, 1967 GB 848463 9, 1960 (86). PCT No.: PCT/US2OO4/O25968 WO WO94/09763 5, 1994 S371 (c)(1), * cited by examiner (2), (4) Date: Jul. 13, 2006 Primary Examiner — Necholus Ogden, Jr. (87) PCT Pub. No.: WO2005/075623 (74) Attorney, Agent, or Firm — Edward D. Korompai (65) Prior Publication Data The present invention provides acylalkylisethionate esters useful in consumer products. The acylalkylisethionate esters US 2008/O234159 A1 Sep. 25, 2008 are produced by reacting one or more carboxylic acids with O O one or more alkyl-substituted hydroxyalkyl sulfonates under Related U.S. Application Data esterification reaction conditions. The alkyl-substituted (60) Provisional application No. 60/537,511, filed on Jan. hydroxyalkyl Sulfonates used as a raw material in producing 20, 2004. the esters are prepared by reacting bisulfite with one or more alkylene oxides. (51) Int. Cl. A6 IK3I/00 (2006.01) 13 Claims, 3 Drawing Sheets U.S. Patent Aug. 30, 2011 Sheet 1 of 3 US 8,008,239 B2 U.S. Patent Aug. 30, 2011 Sheet 2 of 3 US 8,008,239 B2 ?ae % § :*:38. U.S. Patent Aug. 30, 2011 Sheet 3 of 3 US 8,008,239 B2 US 8,008,239 B2 1. 2 ACYLALKYLISETHONATEESTERS AND FIG. 2B depicts the foaming characteristics of sodium APPLICATIONS IN CONSUMER PRODUCTS lauryl ether sulfate (SLES) and sodium lauryl sulfate (SLS); and CROSS-REFERENCE TO RELATED FIG.3 depicts the solubility of solutions containing one of APPLICATION SCI, SCMI and SCEI. This application claims priority to U.S. provisional patent DETAILED DESCRIPTION OF THE INVENTION application Ser. No. 60/537,511, filed Jan. 20, 2004. The present invention provides highly soluble, hydrolyti FIELD OF THE INVENTION 10 cally stable, high-tight foaming, mild (i.e. non-irritating)acy lalkylisethionate esters useful as a primary or secondary Sur The present invention is directed to the preparation of salts factant in aqueous and non-aqueous consumer products such of acylalkylisethionate esters, intermediates in their produc as personal care cleansers. An acylalkylisethionate ester tion, and their application in consumer products. herein refers to an alkyl-substituted acylalkylisethionate ester 15 in which at least one hydrogen on the alkyl chain of the isethionate portion of the molecule is substituted with an alkyl BACKGROUND OF THE INVENTION group. That is, an alkyl group is Substituted onto at least one carbon atom of the alkane Sulfonate portion of the acylalky Acylalkylisethionate esters are anionic Surfactants that can lisethionate ester. For example, in one embodiment, the alkyl be used in a variety of personal care cleansers such as Soaps, substituted acylalkylisethionate ester is an alkyl-substituted cosmetic compositions, and cleaning formulations. One acy acylethylisethionate ester having the following general for lalkylisethionate ester, sodium cocoylisethionate (“SCI), is mula (I): an ester currently used extensively in soap-combi bars (i.e. syndet bars) due to its low solubility in water and mildness (i.e. non-irritating) to the skin as compared to harsher fatty 25 R R2 acid soap bars. However, because of its low water solubility, SCI is not suitable for use in liquid cleansers. One method for R-COO-CHCH-SOX improving SCI's limited water solubility is to combine SCI with other Surfactants such as taurate, amphoacetates and in which Ris any hydrocarbon group having between 4 and 25 betaines. However, this combination of surfactants still pro 30 carbon atoms; R and R are each independently selected duces a hazy solution that tends to separate during storage. from the group consisting of hydrogen and a branched or Therefore, it would be desirable to produce acylalkylisethion straight aliphatic C to Calkyl group subject to the proviso ate esters that are highly water soluble, hydrolytically-stable that only one of R and R is a branched or straight aliphatic and non-irritating for use in aqueous as well as non-aqueous C to C alkyl group while the remaining R or R is hydro consumer products such as personal care cleansers. 35 gen; and X may be any cationic species present for charge neutrality Such as hydrogen, an alkali metal Such as Sodium, SUMMARY OF THE INVENTION potassium and lithium, calcium, magnesium, zinc, alumi num, ammonium and ammonium ions which are substituted The present invention includes alkyl-substituted hydroxy with one or more organic groups. alkyl Sulfonates and methods of preparing alkyl-substituted 40 In another embodiment, the alkyl-substituted acylalkyl hydroxyalkylsulfonates. The alkyl-substituted hydroxyalkyl isethionate ester is an alkyl-substituted acylpropylisethionate sulfonates may then be reacted with a carboxylic acid to ester having the general formula (II): produce acylalkylisethionate esters. The acylalkylisethionate esters may be used as a surfactant or Surface active agent in consumer products such as personal care cleansers. The acy 45 lalkylisethionate esters of the present invention are at least as R-COO-CH-CH-CH-SOX mild to skin as SCI. In addition, unlike SCI, the acylalkyl isethionate esters of the present invention are low foaming, highly soluble in water, and hydrolytically stable making the in which Ris any hydrocarbon group having between 4 and 25 esters easier to handle, store, and compound. Because of their 50 carbon atoms; R and R2 and R are each independently enhanced solubility properties, the alkyl-substituted acyla selected from the group consisting of hydrogen and a lkylisethionate esters can be dissolved in water or flaked into branched or straight aliphatic C to C alkyl group Subject to a fast-dispersing concentrate thus making their use in the the proviso that one of R and R2 and R is a branched or formulation of aqueous and non-aqueous consumer products straight aliphatic C to Calkyl group while the remaining R highly desirable. 55 or R or R is hydrogen; and X may be any cationic species present for charge neutrality Such as hydrogen, analkali metal BRIEF DESCRIPTION OF FIGURES Such as Sodium, potassium and lithium, calcium, magnesium, Zinc, aluminum, ammonium and ammonium ions which are For a detailed understanding and better appreciation of the Substituted with one or more organic groups. present invention, reference should be made to the following 60 The alkyl-substituted acylalkylisethionate esters of the detailed description of the invention, taken in conjunction present invention may be prepared by direct esterification of with the accompanying figures. one or more alkyl-substituted hydroxyalkylisethionates with FIG. 1 is a graph depicting the hydrolytic stability of one or more carboxylic acids. Esterification occurs by mixing Sodium cocoyl isethionate (SCI), Sodium cocoyl methyl alkyl-substituted hydroxyalkyl isethionate with carboxylic isethionate (SCMI) and sodium cocoyl ethyl isethionate 65 acid and optionally an esterification catalyst under esterifica (SCEI) over a time period of 30 days; tion conditions. The alkyl-substituted hydroxyalkylisethion FIG. 2A depicts the foaming characteristics of SCMI; ate can be present as the salt of the alkyl-substituted hydroxy US 8,008,239 B2 3 4 alkyl isethionate or in its acidic form. Thus, esterification for In another embodiment, propylene oxide is reacted with one embodiment may occur according to the reaction: sodium bisulfite to produce sodium 2-methyl 2-hydroxy ethane sulfonate and/or sodium 1-methyl 2-hydroxyethane sulfonate or a mixture thereof. In yet another embodiment, R butylene oxide is reacted with sodium bisulfite to produce Sodium 2-ethyl 2-hydroxyethane Sulfonate and/or sodium R-COH + Hocietix e 1-ethyl 2-hydroxyethane sulfonate or a mixture thereof. In O still another embodiment, a mixture of propylene oxide and O RI RO butylene oxide is reacted with sodium bisulfite to produce 10 Sodium 2-methyl 2-hydroxyethane Sulfonate, Sodium 2-ethyl R-CO-CHCHSOX -- 2-hydroxyethane Sulfonate, sodium 1-methyl 2-hydroxy O ethane Sulfonate, and/or sodium 1-ethyl-2-hydroxyethane sulfonate, or mixtures thereof. The propylene oxide and buty lene oxide or ethylene oxide can be combined in any propor in which R is any hydrocarbon group having between about 4 15 tion to obtain the desired amounts of each alkyl-substituted and about 25 carbon atoms, including straight-chain, hydroxyethane Sulfonate. branched, saturated, and unsaturated hydrocarbon groups; R. In producing an acylalkylisethionate ester by the reaction and R may each independently be hydrogen oran alkyl group of a carboxylic acid with an alkylisethionate.