ACYLOXYALKANE SULFONATE AND AMPHOTERIC SURFACTANT BLEND COMPOSITIONS AND METHODS FOR PREPARING SAME

BACKGROUND OF THE PRESENT INVENTION

The present invention relates to an improved process for preparing combinations of acyloxyalkane sulfonates and amphoteπce and/or anionic surfacntants in high purity and low salt content Acyl isethionates. broadly classed as acyloxyalkane sulfonates, are know ingredients useful in synthetic detergetn bars (syndet bars), shampoos, body washes, bubble baths, creams and loations. The preferred isethionate is sodium cocoyl isethionate

(SCI).

The reaction of acid chlorides ot carboxylic acids with 2-amino- or 2- hydroxyalkanesulfonic acids and their alkali metal salts yeild anionic surfanctants) (for example, sodium N-acyltaurates and sodium acyhsethionates. respectively) is well known as the Schotten-Baumann synthesie

Acyl isethionates. broadly classed as acyloxyalkane sulfonates, are known ingredients useful in synthetic detergent bars (syndet bars), shampoos, body washes, bubble baths, creams and lotions. The preferred isethionate is sodium cocoyl isethionate (SCI).

The reaction of acid chlorides of carboxylic acids with 2-amιno- or 2- hydroxyalkanesulfonic acids and their alkali metal salts to yield anionic surfactants (for

example, sodium N-acyltaurates and sodium αcvlisethionates, respectively) is well known as the Schotten-Baumann svnthesis

The Schotten-Baumann chemistn is very laborious and costly, requiring the handling of hazardous raw materials such as phosphorus trichloride and intermediates like acid chlorides as well as wastes like phosphorus acid Large quantities of waste products are generated as a result of this chemistrv Also the finished products contain significant amounts of sodium chloride as an undesirable by-product The removal of the sodium chloride is possible, but expensive

Sodium acylisethionate svnthesis lias been greatly improved by the direct esterification of sodium isethionate with fatt\ acids This direct esterification route is cost-effective and these products are suitable for use in commercial toilet soap and personal care preparations

The preparation of such sulfonate esters bv direct esterification of a hydroxyalkyl sulfonate with a fatty acid has presented dilficulties because of the high temperature required to obtain suitable conversion At temperatures required for direct esterification, usually in the range of 220° to 250°C , the molten reaction product rapidly degrades in color and loses activity It has been found necessan to rapidly cool the reaction mass in order to obtain a high active final product On method ot quenching involves pouring the molten reaction mixture into a flaker er. this method requires that the product be molten at the decomposition temperature lor a long period of time before the mateπal is allowed to flow into the flaker Thus there is a tradeoff on flowablity verses decomposition In an alternative method I S patent 3.429.136 teaches injecting cold water directly into the molten crude reaction mixture to cool the mass by evaporative cooling below a temperature at which rapid discoloration would occur and this can be done without causing appreciable hydrolvsis of the ester

Since the crude reaction product ordinaπh contains unreacted fatty acid, sulfonate or both, various methods have been proposed tor purification Generally these methods comprise forming liquid svstems in which the impurities are soluble and the product is

insoluble. Following cooling, the soluble impurities can be separated with the liquid by filtration means.

U.S. Patent 4.515.721 teaches that excess fatty acid can be removed from an isethionate reaction mixture by quenching the hot crude fatty acid ester by immersion in a liquid in which the desired ester product is insoluble and the unreacted fatty acid soluble The phases are separated to affect purification In this patent the isethionate can be quenched in vanous products including lov\er chain length alcohols, fatty alcohols, fatty alcohol ethoxylates, polyethylene glycols. polyoxyalkylene derivatives of polyethylene glycol, fatty tπglyceπdes. fatty esters and fatty amides The preferable quenching liquid is isopropanol.

U S. Patent 4.612.132 describes a process for preparing an aqueous surfactant solution and gel of an acyloxyalkane sulfonate salt by combining the sulfonate salt with a water soluble polyol and water This mixture is heated above the boiling point of water under super atmospheric pressure to form a reversible solid colloidal solution from which the product can then be recovered See also. U S. Patent 4.696.767

When SCI is employed in conventional soap bar manufacture, SCI is added as a fine particulate solid to an agglomerator containing soap pellets or chips, known as the soap base. The SCI in this fine particulate phase, can induce sneezing, tearing and or coughing, and tends to be so readily transmitted in the atmosphere as to contaminate other products and compositions made in the same plant environment While SCI is available in larger particle sizes, they are not capable ot homogenization in the several processing stages employed in the manufacture of syndet bars

SCI has limited solubility in water While blends of SCI and aqueous solutions of surfactant can be made, they are of low SCI concentration if a liquid or in the form of a suspension or paste if of a higher SCI content U.S patent 5,415,810 discloses that blends of SCI and betaιnes(zwιtteπonιcs) can be made in an aqueous system where the zwitterionic surfactant assists in the dissolution of the isethionate

It has now been discovered that loxyalkane sulfonate salts may be prepared in liquid, paste or gel forms containing various other surfactants in such a way as to avoid the disadvantageous properties of the SCI itself while performing the required process of

quenching the molten material to form a stable product. Further, the problem of utilizing very fine particles is avoided along with the inherent environmental problems associated therewith.

SUMMARY OF THE PRESENT INVENTION

In accordance with the present invention, it has been discovered that improved aqueous detergent liquid, paste or gel compositions of acyloxyalkane sulfonates and amphoteπc and/or anionic surfactants can be prepared while overcoming the numerous problems of the pnor art with regard to the use of SCI mentioned in the preceding. The surfactant composition of the invention is prepared by quenching a molten reaction mixture of the acyloxyalkane sulfonate in an aqueous solution of an amphoteric and/or anionic surfactant thereby reducing the temperature of the molten acyloxyalkane sulfonate below decomposition temperature, overcoming the problem of decomposition by eliminating extensive holding al high temperatures, greatly enhancing the solubility of the acyloxyalkane sulfonate and forming mixtures of acyloxyalkane sulfonates and amphoteric and/or anionic surfactants and other optional ingredients.. Preferably, the surfactant which is in the quenching liquid is an amphoteric surfactant, preferably a betaine and the acyloxyalkane sulfonate is preterabh SCI By this process, blends of surfactants can be made of materials which are normally utilized together in the final end use area such as syndet bars, liquid detergent compositions, body washes, dish liquids, shampoos and the like The present process allows for the intimate mixture of the surfactants without the need to solidify or isolate the SCI such as by the use of flakers as presently known in the prior art and to avoid the use of finely divided SCI which must be used because of difficulties in homogenizing a blend of larger SCI flakes with other materials.

Further, high active SCI can be quenched in the surfactant-containing quench liquid at a faster rate than required for flaking thus avoiding the need for the addition of the excess fatty acid as a matrix to insure stability while still reducing decomposition.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The present invention relates to an aqueous surfactant solution or gel comprising an acyloxyalkane sulfonate salt of the general formula:

R,-C(0)-0(CH ₂ ) _n S0 ₃ Y wherein R] is a hydrocarbyl radical, desirably from about 6 to about 26 carbon atoms, n is integer of from 2 to 4, preferably 2 and Y is an alkali metal or alkaline earth metal, more particularly, sodium, potassium, lithium or magnesium and preferably sodium. The alkane portion of the sulfonates of Formula 1 for use herein includes ethylene and branched or unbranched propylene or butylene. The fatty alkyl moiety R, is a hydrocarbyl containing from about 6 to about 26 carbon atoms and preferably from about 6 to about 20 carbon atoms such as hexanoic. octanoic, decanoic, dodecanoic, lauric, behenic, palmitic, stearic. myristic. arachidic. oleic. linolenic. linoleic and the like including mixtures of the foregoing as in the particularly preferred cocoyl derivatives from coconut oil fatty acids. Fatty acids from natural sources are comprised of numerous fatty acids that all general ly fall within the state carbon range. A small proportion of mono - or di - unsaturated fatty acid derivatives may be desirable to provide adequate foaming and solubility in blends containing the neat soap. Normally, the degree of unsaturation will not be less than about 2 or more than 12. when measured by iodine number. It will be observed in this context that the term "hydrocarbyl" is intended to embrace linear and branched aliphatic radicals that include alkyl, alkenyl. alkynyl, and aikadienyl moieties. Too large a proponion of unsaturation. tends to render the sulfonate susceptible to oxidative degradation. The preferred compounds are acyl isethionates, preferably cocoisethionates.

The acyloxyalkane sulfonates are prepared by the direct esterification of a hydroxyalkane sulfonic acid with a fatty acid. The reaction can be conducted using well documented procedures. Temperatures of reaction are sufficient to effect reaction and maintain the product molten but not sufficiently high to cause substantial decomposition under normal product working conditions. Temperatures within the range of from about 180°C. to about 250° C. have been found to be effective. Since excess fatty acid is used as solvent, the molten reaction mixture contains the desired product along with excess fatty acid and sulfonate reaction material impurities. The reaction is conducted for a

period of time sufficient to achieve conversion but insufficient to allow substantial product degradation, for example from about 1 to about 8 hours.

In accordance with the invention, the molten reaction product is quenched in an aqueous solution of amphoteric and/or anionic surfactant at a rate sufficient to cool the reaction mass below degradation temperature

Λmphoteπc/ Zwitterionic Surfactants. Amphoteric surfactants useful in the invention can broadly be described as a surface active agent containing at least one anionic and one cationic group and can act as either acids or bases depending on pH Some of these compounds are aliphatic denvatives of heterocyclic secondary and tertiary amines in which the aliphatic radical may be straight or branched and wherein one of the aliphatic substituents contains from about 6 to about 20, preferably 8 to 18. carbon atoms and at least one contains an anionic water-solubilizing group, e g . carbox\ , phosphonate. phosphate, sulfonate, sulfate. Zwitterionic surfactants can be broad 1> descπbed as surface active agents having a positive and negative charge in the same molecuie which molecule is zwitterionic at all pHs. Zwittenonic surfactants can be best illustrated by betaines and sultaines. The zwitterionic compounds generally contain a quaternary ammonium, quaternary phosphonium or a tertian sulfonium moιet\ The cationic atom in the quaternary compound can be part ot a heterocyclic πng ln all of these compounds there is at least one aliphatic group, straight chain or branched, containing from about 6 to 20, preferably 8 to 18, carbon atoms and at least one aliphatic substituent containing an anionic water- solubilizmg group, e.g.. carboxy. sulfonate. sulfate. phosphate or phosphonate.

Examples of suitable amphoteric and zwitterionic surfactants include the alkali metal, alkaline earth metal, ammonium or substituted ammonium salts of alkyl amphocarboxyglycinates and alkyl amphocarboxypropionates. alkyl amphodipropionates, alkyl monoacetate, alkyl diacetates, alkλ 1 amphoglycinates, and alkyl amphopropionates wherein alkyl represents an alkyl group ha\ ing from 6 to about 20 carbon atoms Other suitable surfactants include alkyhminomonoacetates. alkyhminidiacetates, alkyliminopropionates, alkvhminidipropionates. and alkylamphopropylsulfonates having

between 12 and 18 carbon atoms, alkyl betaines and alkylamidoalkylene betaines and alkyl sultaines and alkylaπudoalkyleneh\ droxy sulfonates.

Particularly useful amphoteric surfactants include both mono and dicarboxylates such as those of the formulae

O CH.CFLOH

" / ^{' '}

R—C— NHCILCH,N (I); and

(CHA COOM

O QLCHiOH (CH,) _x COOM R— C ιι— N ' CH _; CH ₃ N / (II);

(CH.χCOOM

( CHACOOM

R — N and (III);

(CILX COOM

wherein R is an alkyl group of 6-20 carbon atoms, x is 1 or 2 and M is hydrogen or sodium. Mixtures of the above structures are paniculariv preferred

Other amphoteric surfactants can be illustrated b\ the following formulae:

Alkyl betaines

CH ₃ R— ⁺ N— CH ₂ COO ^" (IV) CH ₃

Amidopropyl betaines

O CH, II I

R— C— NH— CH ₂ CH ₂ CH ₂ — ⁺ N— CH ₂ COO ^" (V)

CH ₃

Alkyl sultaines

CH ₃

R— N ⁺ — CH ₂ — CH- - C1LSO, ^" (VI); and

CH ₃ OH

Alkyl amidopropylhydroxy su Itaines

0 CI I,

II

II

R— C- -NH— CH,CH _: CI I ₂ — - ^~ N — ( :H ₂ — CH— CH ₂ S0 ₃ (Vii);

CH, OH wherein R is an alkyl group of 6-20 carbon atoms.

Of the above amphoteric surfactants, particularly preferred are compounds wherein the alkyl group is derived from natural sources such as coconut oil or is a lauryl group. In reciting a carbon chain length range, it is intended to include groups such as coco which are naturally derived materials which have various specific chain lengths or an average chain length within the range.

Commercially useful and preferred amphoteπc surfactants include (as sodium salts): cocoamphoacetate (sold under the trademarks MIRANOL ^® CM CONC. and MIRAPON ^®

FA, and MIRANOL ^® ULTRA C-32 (preferred). cocoamphodiacetate (sold under the trademarks MIRANOL ^® C2M CONC. and

MIRAPON^ FB), ccooccooaammpphhoopprrooppiioo:nate (sold under the trademarks MIRANOL ^® CM-SF CONC. and MIRAPON ^® FAS) ccooccooaammpphhooddiipprrooppiiionate (sold under the trademarks MIRANOL ^® C2M-SF and MIRANOL ^® FBS).

lauroamphoacetate (sold under the trademarks MIRANOL ^® HM CONC. and MIRAPON ^®

LA), lauroamphodiacetate (sold under the trademarks MIRANOL ^® H2M CONC. and

MIRAPON ^® LB), lauroamphodipropionate (sold under the trademarks MIRANOL ^® H2M-SF CONC AND

MIRAPON ^® LBS), lauroamphodiacetate obtained trom a mixture of lauπc and mynstic acids (sold under the trademark MIRANOL ^® BM CONC). and cocoamphopropyl sulfonate (sold under the trademark MIRANOL ^® CS CONC.) Somewhat less preferred are caproamphodiacetate (sold under the trademark MIRANOL ^® S2M CONC), caproamphoacetate (sold under the trademark MIRANOL^ SM CONC), caproamphodipropionate (sold under the trademark MIRANOL ^® S2M-SF CONC), and stearoamphoacetate (sold under the trademark MIRANOL* DM). As used herein the term 'ampho ^'" is intended to refer to a structure derived from imidazohne chemistry. Vaπous structures have been assigned to these products and the following are representative ( \ is as defined hereinbefore)

O

— CNHCH ₂ CH ₂ N _N

O

The quench liquid can also contain as the soie surfactant an anionic surfactant or the anionic surfactant can be coblended w ith an amphoteric surfactant during the quenching or after quenching

Anionic Surfactants

Anionic surfactant detergents which may be included in the quench liquid used in the invention are those surfactant compounds which contain a long chain hydrocarbon hydrophobic group in their molecular structure and a hydrophilic group, including 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.

Amoruc surfactants mclude the alkali metal, ammonium and alkanol ammomum salts of organic sulfuric reaction products having in their molecular structure an alkyl, or alkaryl group containing trom 8 to 22 carbon atoms and a sulfonic or sulfuric acid ester group. Examples of such anionic surfactants include water soluble salts of alkyl benzene sulfonates having between 8 and 22 carbon atoms in the alkyl group, alkyl ether sulfates having between 8 and 22 carbon atoms in the 1 group and 2 to 9 moles ethylene oxide in the ether group. Other anionic surfactants that can be mentioned include aikyl sulfosuccinates, alkyl ether sulfosuccinates. oiefin sulfonates, alkyl sarcosinates. alkyl monoglyceride sulfates and ether sulfates. alk\ I ether carboxylates, paraffinic sulfonates, mono and di alkyl phosphate esters and lated deπtives, acyl methyl taurates, fatty acid soaps, collagen hydrosylate derivatives, sulfoacetates, acyl lactates, aryloxide disulfonates, sulfosucinainides. naphthalenc-tormaldehyde condensates and the like. Aryl groups generally include one and two rings, alkyl generally includes from 8 to 22 carbon atoms and the ether groups generalK range from 1 to 9 moles of EO and/or PO, preferably EO.

Specific anionic surfactants which ma> be selected include linear alkyl benzene sulfonates such as decylbenzene sulfonate. undecylbenzene sulfonate, dodecylbenzene sulfonate, tridecylbenzene sulfonate. nom lbenzene sulfate and the sodium, potassium, ammonium, tπethanol ammonium and ιsoprop\ 1 ammonium salts thereof. Particularly

preferred sulfonate salt is sodium dodecylbenzene sulfonate Such chemicals have been sold under the trade name Biosoft B 100 b> Stepan Chemicals of Northfield, Illinois. Other anionic surfactants include polyethoxylated alcohol sulfates, such as those sold under the trade name Neodol 25-3S by Shell Chemical Company. Examples of other anionic surfactants are provided in U.S Pat. Nos 3,976,586 and 5,415,810 To the extent necessary, these patents are expressly incorporated herein by reference.

In addition to the amphoteric and/oi anionic surfactants, the quench liquid used in the process of the invention can optionalh comprise one or more of a nonionic or cationic surfactants as well as other optional ingredients

Nonionic Surfactants The quench liquid of the invention can optionally also include one or more nonionic surfactants. The nonionic surfactant(s) is not critical and may be any of the known nonionic surfactants which are generalK selected on the basis of compatibility, effectiveness and econom\

Examples of useful nonionic sui tactants include condensates of ethylene oxide with a hydrophobic moιet\ which has an average hydrophilic hpolytic balance (HLB) between about 8 to about 16. and preterabh between about 10 and about 12.5. The surfactants include the ethoxylated pπmar\ or secondary aliphatic alcohols having from about 8 to about 24 carbon atoms, in either straight or branch chain configuration, with from about 2 to about 40. and preferably between about 2 and about 9 moles of ethylene oxide per mole of alcohol

Other suitable nonionic surfactants include the condensation products of from about 6 to about 12 carbon atoms alkyl phenols with about 3 to about 30, and preferably between about 5 to about 14 moles of ethylene oxide Examples of such surfactants are sold under the trade names Igepal CO 530. Igepal CO 630. Igepal CO 720 and Igepal CO 730 by Rhόne-Poulenc lnc Still other suitable nonionic surfactants are described in U.S. Pat. No. 3,976,586 which, to the extent necessary, is expressly incorporated herein by reference.

Cationic Surfactants 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. Such compounds are described in "Cationic Surfactants", Jungermann. 1970. incoφorated herein by reference.

Specific cationic surfactants which can be used as surfactants in the invention are described in U.S. Pat. No 4.497,718. incorporated herein by reference

As with the nonionic and anionic surfactants, the compositions the invention may use cationic surfactants alone but preferably in combination with other surfactants as is known in the art The composition of the invention can contain any useful amount but preferably up to about 20° o weight oi surfactant actives based on the total surfactant actives weight in the quench liquid Of course, the composition may contain no cationic surfactants at all.

pH Adjusting Chemicals pH adjusting chemicals such as acids, bases and buffers can be added to the quench liquid. Prefeπed pH adjusting chemicals include lower alkanolamines such as monoethanolamine (MEA ) and triethanolamine (TEA) Sodium hydroxide solutions may be utilized as an alkaline pH adjusting agent T hese solutions further function to neutralize acidic materials that may be present Mixtures of more than one pH adjusting chemical can also be utilized

Optional Ingredients In addition to essential ingredients described hereinbefore, the quenching liquid of the present invention can also contain a series of optional ingredients which are used for known functionality at conventional levels

The quenching liquid of the invention can contain phase regulants (well known liquid detergent technology). These can be represented by lower aliphatic alcohols having from 2 to 6 carbon atoms and from 1 to 3 hydroxyl groups, ethers of diethylene glycol and lower aliphatic monoalcohols having from 1 to 4 carbon atoms and the like.

Detergent hydrotropes could also be included. Examples of these hydrotropes include salts of alkylarylsulfonates having up to 3 carbon atoms in the alkyl group e.g., sodium, potassium, ammonium, and ethanolamine salts of xylene, toluene, ethylbenzene, cumene, and isopropylbenzene sulfonic acids Other supplemental additives include defoamers such as high molecular weight aliphatic acids, especialK saturated fatt\ acids and soaps derived from them, dyes and perfumes; fluorescent agents or optical brighteners; anti-redeposition agents such as carboxymetJryl cellulose and hydroxypropylmethyl cellulose, suspension stabilizing agents and soil release promoters such as copolymers of polyethylene terephthalate and polyoxyethylene terephthalate. antioxidants. softening agents and anti-static agents; photo activators and prescn atives. poh acids, suds regulators, opacifiers, bactenacide, and the like. Suds regulants can illustrated b> alkylated polysiloxanes and opacifiers can be illustrated by polystyrene, bacteπcide can be illustrated by butylated hydroxytoluene.

Although not required, an inorganic or organic builder may optionally be added in small amounts to the final composition Examples of inorganic builders include water- soluble alkali metal carbonates, bicarbonates. silicates and crystalline and amorphous alumino silicates. Examples of organic builders include the alkali metal, alkaline metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates, polyacetyl, carboxylates and polyhydroxx sulfonates One example of a commonly used builder is sodium citrate.

The optional ingredients, pH adjusting chemicals and optional surfactants can be added to the quenching liquid before, during or after quenching as desired or as practical. Blends can be made directly for sale or tor compounding to meet the needs of the user.

The molten reaction mixture is added to the quench liquid at a rate sufficient to effectively cool the reaction mixture beneath the degradation temperature without over heating the quench liquid. Rate of addition, quantity, heat transfer capabilities as well as the total solids desired in the final product will control and these can be readily determined by one of ordinary skill in the art

Quenching is conducted using good chemical manufactuπng techniques. The molten reaction product is preferably transferred directly to a quench vessel containing

the quench liquid but can be conducted through heated piping to maintain the reaction product in molten condition. The quench vessel is preferably equipped with an agitator and a cooling jacket. While a pressurized \ essel could be use. this would require a pump to overcome the difference in pressure between the reaction vessel and the quench vessel while maintaining molten flow. The quench vessel is preferably equipped with a condensation means for condensing the water evaporated from the quench liquid during quenching. The condensate is preferably leintroduced into the quench liquid.

The molten material being quenched generalh can contain from about 80% to about 95%, generally around 90%. actn es. the remainder of the solids being impurities and reactants. The amount of actives depends on the efficiency of fatty acid removal from the reaction mixture. The molten mateπal is added to sufficient quenching liquid to reduce the temperature of the reaction mixture below the decomposition temperature of the reaction product. Larger amounts of quench liquid can be desirable to absorb more heat. The amount of reaction product quenched is not a function of the degree of solubility of the reaction product in the quenching liquid The amount of reaction product quenched could be above or below the solιιbilit\ limn of the reaction product in the quenching liquid.

It is preferred that the total solids in the quenching liquid after quenching (not including solids added after quenching is complete ) not exceed about 60%, preferably about 50% and more preferably about 45% Included in the solids are the reaction product, the amphoteric or anionic surfactant, the optional surfactants, and the remaining optional ingredients including the pH adiustmg chemicals. The ratio of reaction product to amphoteric and/or anionic surfactant can be expressed as ranging from about 85% - !5% reaction product to about 15% to about 85% amphoteric and/or anionic surfactant based on solids. It is preferable to use trom about 40% to about 60% and from about 60%o to about 40% and more preferabK about 50% to about 50% reaction product to amphoteric and/or anionic surfactant

When using a blend of amphoteric and anionic surfactants in the quench liquid, one can use from a negible amount of amphoteric surfactant to slightly less than 100% with the complementary ranges for the anionic surfactant. It is preferable to use from

about 30% to about 70% amphoteric surfactant to about 70% to about 30% anionic surfactant on a solids basis and more preferably from about 45% to about 55% amphoteric surfactant to about 55% to about 45% anionic surfactant on a solids basis.

The nonionic surfactant based on total solids in the quenching liquid should not exceed about 20%; the cationic surfactant not more than about 10% of the solids and the optional ingredients not more than 10% ot the total solids

After quenching, the quenched material can be cooled and used as is or further purified such as by redissolving in a lower aliphatic alcohol, e.g., isopropanol. The product can be a pumpable liquid or a paste depending on the concentration of the ingredients. Higher levels of acyloxyalkane sulfonate lead to gels so that it may be desirable to use lower levels to prepare pumpable products

The blends of the invention can be used directK in various personal care and household cleaning products or blended w ith further ingredients as desired. By this invention, blends of ingredients can be made using the product of the invention as a base. The present invention will be moi e fully illustrated in the following non-limiting examples.

EXAMPLES 1 -5 Reaction Equipment:

The reaction kettle is an oil ιackeιcd 4 necked 2 liter resin pot with a drip tip drain equipped with a mechanical stirrer. thermometer, nitrogen sparge, and Dean Starke trap leading to a reflux condenser. The kettle dram is connected to a 5 liter three neck round bottom flask equipped with a stirrer and reflux condenser Procedure

To the reaction kettle described above was added 339.4 grams ( 1.63 M) coconut tatty acid

1.2 grams zinc oxide catalyst This reaction mixture was heated to 180°-200°C w ith stiπing under nitrogen purge. Over 1 hour 290.4 grams (55% solids. 1 .08 M) aqueous sodium isethionate solution was then charged.

After addition was complete, the reaction mixture was heated to 230°C and held for 2 hours until water evolution ceased. 150 grams water was removed. Excess coconut fatty acid was removed by vacuum distillation. Removal of 100 grams of fatty acid resulted in a product 88% active by methv lene blue analysis containing 7% coconut fatty acid. The product at approximately 180°C-200°C was drained into the 5 liter flask containing an aqueous solution of cocoamidopropylbetaine (1325 grams cocoamidopropylbetaine - MIRATAINE® CABA at 35% solids and 950 grams water). The product was a viscous liquid.

Various compositions were prepared in like manner and are tabulated as follows:

TABLE I

EXAMPLE 1 2 4 5

Ingredient Wt.% Wt.% Wt.% Wt.% Wt.%

Na Cocoyl isethionate 15 20 30 20 30

Water 35 30 20 30 20

Cocoamido propylbetaine* 50 50 50 - - (35% Solids)

Na Cocoamphoacetate** -- — — 50 50 ( % solids)

Observations

Physical Appearance Viscous Paste Paste Viscous Paste Liquid Gel

Viscosity 9400 92000 cPs cPs

* MIRATAINE CABA ** MIRANOL ULTRA C-32

MIRATAINE & MIRANOL are trademarks of Rhόne-Poulenc Inc.