MXPA06002371A - Methods of reducing irritation in personal care compositions - Google Patents

Abstract

Provided are methods of reducing the irritation associated with a personal care composition comprising an anionic surfactant, the methods comprising combining a hydrophobically-modified material capable of binding a surfactant thereto with ananionic surfactant to produce a reduced irritation personal care composition, and methods ofusing such compositions to cleanse the hair or skin with reduced irritation.

Description

METHODS TO REDUCE IRRITATION IN COMPOSITIONS FOR PERSONAL CARE RECIPROCAL REFERENCES TO RELATED REQUESTS This request is a continuation-in-part of the requests for E.U.A. Nos. 10 / 650,226, 10 / 650,495, 10 / 650,573, and 10 / 650,398, each of which was submitted on August 28, 2003, and is currently pending.

Each of the aforementioned applications is incorporated herein by reference.

FIELD OF THE INVENTION The present invention relates to methods for reducing the irritation characteristics associated with a variety of personal care compositions, and methods for using said compositions.

DESCRIPTION OF THE RELATED TECHNIQUE Synthetic detergents, such as cationic, anionic, amphoteric, and nonionic surfactants, are widely used in a variety of detergents and cleaning compositions. For many such compositions, including, for example, shampoos, it is desirable to use a surfactant which imparts or provides the composition with a relatively high foam volume and foam stability when incorporated in the present invention. It is generally recognized that such properties of the foam directly relate to the observed efficiency with which a shampoo cleans the hair. That is, the greater the volume of foam produced and the greater the stability of the foam, the greater efficiency in the cleaning action observed by the shampoo. Anionic surfactants tend to exhibit superior cleaning and foaming properties, and are therefore incorporated into many personal cleansing compositions. However, these anionic surfactants also tend to be very irritating to the skin and eyes. In order to produce milder cleaning compositions, it is well known to replace some of the anionic surfactants in these with other surfactants, such as nonionic and / or amphoteric surfactants. See, for example, U.S. Patent No. 4,726,915. Another method for producing mild cleaning compositions is the association of the anionic surfactants with amphoteric or cationic compounds in order to produce complexes of surfactant. See, for example, U.S. Patent Nos. 4,443,362; 4,726,915; 4,186,113; and 4,110,263. Disadvantageously, the mild cleaning compositions produced by both methods tend to suffer from poor foam formation and cleaning performance.

In addition, recent literature, Moore, P .; Shiloach, A .; Puwada, S .; Biankschiein, D. Journal of Cosmetic Science, 54, 2003, 143-159 ("Moore et al.") Have described the addition of polyethylene oxide (PEO) to a solution of water and relatively low concentrations (significantly below the typical levels of personal care cleansing compositions) of sodium dodecyl sulfate (SDS), a cleansing surfactant, to reduce the penetration of SDS into the epidermis of the skin. Moore et al. postulate that by binding the free micelles of the surfactant to it, the PEO forms larger micelles with the SDS, in comparison with the SDS-free micelles, said larger micelles are not able to penetrate the stratum corneum as easily as the smaller free micelles. In this way, Moore et al. they evaluated that the penetration of the surfactant into the skin is mitigated, and that this reduced penetration of the surfactant can lead to reduced irritation of the skin. However, applicants have recognized that the PEO does not bind adequately to the surfactant, and does not provide a significant or adequate reduction in irritation, when added to the compositions comprising higher levels of surfactant than those described in Moore. et al. Because conventional personal care compositions tend to comprise higher levels of surfactant than those described in Moore et al., the applicants have recognized that the teachings of Moore et al. they do not significantly outweigh the disadvantages associated with other methods for mitigating irritation in personal care compositions. In light of the foregoing, applicants have recognized the need for methods for the production of personal care compositions that have reduced irritation to the skin and / or eye without adversely impacting foaming properties and / or other anesthetics associated with these.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides methods to reduce the irritation associated with a variety of personal care compositions such methods overcome the disadvantages of the prior art. In particular, in accordance with certain preferred embodiments of the present invention, applicants have advantageously discovered that hydrophobically modified materials capable of binding to the surfactant can be combined with surfactants to produce personal care compositions that exhibit relatively low irritation to skin and / or eyes, and / or relatively high foaming / foam stability properties. One aspect of the present invention provides methods for the reduction of irritation associated with a personal care composition comprising a surfactant, the method comprising combining a hydrophobically modified material capable of binding a surfactant with a surfactant to produce a composition for personal care with reduced irritation comprising from about 3.5 to less than 7.5 of anionic surfactant, by weight percent, based on the total weight of the composition with reduced irritation. In accordance with another aspect of the present invention, compositions produced in accordance with the present invention are provided. In accordance with yet another aspect of the present invention, methods are provided for cleaning the skin or hair with reduced irritation comprising the step of contacting the skin or hair of a mammal with a composition with reduced irritation comprising a surfactant and a hydrophobically modified material capable of binding to a surfactant.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graphic illustration of the idealized tensiometry data associated with the addition of the anionic surfactant to two solutions. Figure 2 is a graphical illustration of the tensiometry data and the calculated CMC measurement for a composition in accordance with one embodiment of the present invention.

Figure 3 is a graphic illustration of the tensiometry data and the measurement of the Delta CMC calculated for a composition in accordance with one embodiment of the present invention.

DESCRIPTION OF THE PREFERRED MODALITIES All percentages described in the present invention are weight-for-weight percent based on the total weight of the composition, unless otherwise indicated. With respect to reduced irritation, applicants have discovered that the "TEP value" associated with a particular composition, which is conventionally measured via the Trans-Epithelial Permeability Test ("TEP Test") set forth in the Invittox protocol number 86 (May 1994) incorporated in the present invention as a reference and as described in more detail in the examples below, has a direct correlation with the skin and / or eye irritation associated with the composition . More specifically, a higher TEP value of a composition tends to indicate less irritation to the skin and eyes associated with it compared to a composition having a lower TEP value, said composition tending to cause higher levels of skin irritation and / or to the eyes. Applicants have recognized that the present methods are suitable for the production of personal care compositions having surprisingly high TEP values / minor irritation associated therewith. For example, in certain embodiments, the present methods produce compositions having a TEP value of at least about 1.5 or greater. In certain more preferred embodiments, the composition produced according to the present methods exhibits a TEP value of at least about 2 or greater, more preferably, at least about 2.5 or greater, even more preferably, at least about 3 or greater, and even more preferably, at least about 3.5 or greater. In certain particularly preferred embodiments, the compounds exhibit a TEP value of at least about 4.0 or greater, and even more preferably, about 4.5 or greater. In addition, to determine when, and to express the extent to which, a composition comprising an anionic surfactant and a hydrophobically modified material produced via the present methods exhibits reduced irritation as compared to a comparable free composition of the hydrophobically modified material, applicants in the present invention define the term "Delta PET" of a composition of the present invention as the value obtained by: (a) measuring the PET values of: (i) the composition of the present invention comprising an anionic surfactant and hydrophobically modified and (ii) the comparable composition for said composition; and (b) subtracting the TEP value of the comparable composition from the TEP value for the composition of anionic surfactant / hydrophobically modified material. As used in the present invention, the "comparable composition" of a particular composition comprising anionic surfactant and hydrophobically modified material means a composition consisting of the same components in the same relative weight percentages as the composition of anionic surfactant. hydrophobically modified material with the exception that the hydrophobically modified polymer of the anionic surfactant / hydrophobically modified material composition is replaced in the comparable composition with the same relative weight percentage of water. For example, the comparable composition for an anionic surfactant / hydrophobically modified material composition consisting of 7% anionic surfactant, 15% amphoteric surfactant, 5% hydrophobically modified polymer, 5% glycerin, and 68% Water (where all percentages are by weight based on the total weight of the composition) is a composition consisting of 7% anionic surfactant, 15% amphoteric surfactant, 5% glycerin, and 73% water. In addition, as described in the present invention below, the composition of Example 10 is a comparable composition for the anionic surfactant / hydrophobically modified polymer compositions formed in Examples 11-15. In light of the foregoing, as used in the present invention the term "reduced irritation composition" generally refers to a composition comprising an anionic surfactant and one or more hydrophobically modified materials capable of bin the surfactant, said composition has a positive Delta TEP value (eg the composition has a TEP value greater than its comparable composition), measured via the Invittox protocol incorporated in the present invention. Certain preferred compositions with reduced irritation of the present invention include those having a Delta PET of at least about +0.5. Certain more preferred compositions with reduced irritation include those having a Delta PET of at least about +0.75, and more preferably at least about +1. Certain particularly preferred compositions with reduced irritation include those having a Delta PET that is at least about +1.2, more preferably at least about +1.5, and more preferably at least about +1.8. As used in the present invention, the term "hydrophobically modified material" generally refers to any material having one or more hydrophobic portions attached to it or incorporated therein. Examples of certain types of preferred hydrophobically modified materials include hydrophobically modified polymers. Such polymers can be formed, for example, by polymerizing one or more hydrophobic monomers and, optionally, one or more co-monomers, to form a polymer having hydrophobic moieties incorporated therein, and / or also by reacting polymeric materials with compounds comprising hydrophobic portions for attaching said compounds to the polymers. Certain hydrophobically modified polymers and methods for making such polymers are described in the U.S. Patent. No. 6,433,061, issued to Marchant et al. and incorporated in the present invention as a reference. Any of a variety of hydrophobically modified materials capable of bin the surfactant are suitable for use in the present invention. Although the applicants do not wish to abide by these or any particular theory of operation, it is believed that the hydrophobically modified materials suitable for use in the present methods act to reduce the irritation associated with personal care compositions., at least in part, by binding to the surfactant (molecules free of surfactant (unbound) and / or, especially, micelles free of surfactants (unbound)) to reduce the concentration of free micelles that cause the irritation available in the composition to irritate the skin and / or eyes. That is, the applicants have discovered that the relative amounts of surfactant-free micelles contained in a particular composition affect the skin and / or eye-related irritation associated with that composition, where higher amounts of free micelles tend to cause Higher levels of irritation and lower levels of free micelles tend to cause less irritation. By binding surfactant and / or surfactant micelles, the hydrophobically modified materials reduce the concentration of non-bound surfactant micelles in a composition and allow a higher concentration of surfactant to be added to the composition before it is added. form the free micelles and / or before a particular level of irritation is reached. This desirable change in the concentration of the surfactant that is required before the formation of the free micelles is further illustrated in Figure 1. Figure 1 is a graph, marked with the reference numeral 10, which shows the idealized curves of the surface tension data associated with the addition of the anionic surfactant to two compositions, a composition comprising a hydrophobically modified material of the present invention and a comparable free composition of hydrophobically modified material. Curve 11 shows the change in surface tension, measured via conventional tensiometry techniques (the examples of which are described in the present invention below), of a free composition of hydrophobically modified material as increasing levels are added to it of the anionic surfactant. Curve 15 shows the change in surface tension of a composition comprising hydrophobically modified material as increasing levels of the anionic surfactant are added thereto. In curve 11, as surfactant is added to the solution, the surfactant tends to populate the liquid / air interface, thus reducing the surface tension of the solution, until essentially the entire surface area is filled. After this point, hereinafter the "critical micellar concentration (CMC)" of the surfactant, point 12, essentially all the surfactant added to the composition forms free micelles in solution, said formation has no appreciable effect on the surface tension of the surface. the solution, but tends to increase the irritation associated with the composition. In comparison, as shown in curve 15, as anionic surfactant is added to a solution comprising a hydrophobically modified material, the surfactant aligns itself at both the liquid / air interface and binds to the hydrophobically modified material until that the CMC, point 16, changes to a significantly higher concentration of surfactant compared to curve 11, at which point the added surfactant tends to form free micelles. In light of the foregoing, applicants have recognized that a measurement of the efficiency of a particular hydrophobically modified material in the binding of a surfactant can be expressed as the "Delta CMC" that is achieved by combining the hydrophobically modified material with a surfactant to form a composition with reduced irritation. A "Delta CMC" as used in the present invention is defined as the number obtained by: (a) determining the CMC for: (i) a particular composition of the present invention comprising an anionic surfactant and a hydrophobic material modified, and (ii) the comparable composition of the composition in (i), wherein said CMC values are determined using the Reverse test methods for Tensiometry titration defined in the examples below; and (b) subtracting the CMC value obtained for the composition (ii) from the value obtained for the composition (i). In certain embodiments, it is preferred to select a hydrophobically modified material for use in the present methods such that the Delta CMC associated with the resulting composition with reduced irritation is a positive value. In certain more preferred embodiments, the hydrophobically modified material is selected to achieve a reduced irritation composition having a Delta CMC of about +16 or greater, more preferably, about +80 or greater, and even more preferably about +300 or more. higher. Examples of hydrophobically modified materials capable of binding a surfactant and suitable for use in the present methods include hydrophobically modified polymers, for example, hydrophobically modified acrylic polymers, as well as hydrophobically modified cellulosics, hydrophobically modified starches, combinations of two or more of the same ones, and the similar ones. Hydrophobically modified acrylic polymers suitable for use in the present invention may be in the form of random, block, star, graft copolymers, and the like. In certain embodiments, the hydrophobically modified acrylic polymers are crosslinked anionic acrylic copolymers. Said copolymers can be synthesized from at least one acidic monomer and at least one hydrophobic ethylenically unsaturated monomer. Examples of suitable acidic monomers include those ethylenically unsaturated acid monomers that can be neutralized by a base. Examples of suitable hydrophobic ethylenically unsaturated monomers include those containing a hydrophobic chain having a carbon chain length of at least 3 carbon atoms. In another embodiment, the hydrophobically modified anionic acrylic copolymer includes those compositions derived from at least one unsaturated carboxylic acid monomer; at least one hydrophobic monomer; a hydrophobic chain transfer agent comprising alkyl mercaptans, thioesters, compounds or peptide fragments containing amino acid mercaptan, or combinations thereof; an agent for cross-linking; and, optionally, a steric stabilizer; wherein the amount of said unsaturated carboxylic acid monomer is from about 60% to about 98% by weight based on the total weight of said unsaturated monomers and said hydrophobic monomer, as set forth in U.S. Patent No. 6,433,061 , which is incorporated by reference in the present invention. In one embodiment, the polymer is an acrylate copolymer that is commercially available from Noveon, Inc. under the trade name, "Carbopol Aqua SF-1". Any of a variety of hydrophobically modified cellulosics or starches are suitable for use in the present invention.

Examples of suitable hydrophobically modified cellulosics include hydrophobically modified hydroxyethylcellulose (commercially available, for example, from Hercules Inc. (Wilmington, DE) as "Natrosol Plus"), and the like. Examples of suitable hydrophobically modified starches include hydrophobically modified hydroxypropyl starch phosphate (commercially available, for example, from National Starch (Bridgewater, NJ) as "Structure XL"), and the like. In certain preferred embodiments of the present invention, the hydrophobically modified materials comprise hydrophobically modified acrylic polymers, more preferably hydrophobically modified crosslinked anionic acrylic copolymers. Any of a variety of anionic surfactants can be combined with a hydrophobically modified material to form a reduced irritation composition in accordance with the preferred embodiments of the present methods. According to certain embodiments, suitable anionic surfactants include those selected from the following classes of surfactants: alkyl sulfates, alkyl ether sulfates, alkyl monoglyceryl ether sulphates, alkyl sulfonates, alkylaryl sulphonates, alkyl sulfosuccinates , alkyl ether sulfosuccinates, alkyl sulfosuccinamates, alkyl amidosulfosuccinates, alkyl carboxylates, alkyl amidoetherscarboxylates, alkyl succinates, fatty acyl sarcosinates, fatty acyl amino acids, fatty acyl taurates, fatty alkyl sulphoacetates, alkyl phosphates, and mixtures of two or more thereof. Examples of certain preferred anionic surfactants include: alkyl sulphates of the formula Rt-CH1OS03X '; Alkyl ether sulphates of the formula RTCÓCH2CH2) ¥ OS03X '; Alkyl monoglyceryl ether sulphates of the formula R ^ CH2CHCH203G3,; OH Alkyl monoglyceride sulphates of the formula iC02CH2CHCH2? S03X '; OH Alkyl monoglyceride sulfonates of the formula Alkyl sulfonates of the formula Alkylaryl sulfonates of the formula * Alkyl sulfosuccinates of the formula: Alkyl ether sulfosuccinates of the formula: Alkyl sulfosuccinamates of the formula: Alkyl amidosulfosuccinates of the formula Alkyl carboxylates of the formula: R 1 - (OCH 2 CH 2) w * OCH 2 C 0 2 X 1: Alkyl amidoether carboxylates of the formula: Alkyl succinates of the formula: ; Fatty acyl sarcosinates of the formula: Acrylic fatty acid amino acids of the formula: Fatty acrylic taurates of the formula: Fatty alkyl sulfoacetates of the formula: Alkyl phosphates of the formula: wherein R1 is an alkyl group having from about 7 to about 22, and preferably from about 7 to about 16 carbon atoms, R'i is an alkyl group having from about 1 to about 18, and preferably from about 8 to about 14 carbon atoms, R'2 is a substituent of a natural or synthetic l-amino acid, X 'is selected from the group consisting of alkali metal ions, alkaline earth metal ions, ammonium ions, and ions of ammonium substituted with from about 1 to about 3 substituents, each of the substituents may be the same or may be different and are selected from the group consisting of alkyl groups having from 1 to 4 carbon atoms and hydroxyalkyl groups having from about 2 to about 4 carbon atoms and v is an integer from 1 to 6; w is an integer from 0 to 20; and mixtures thereof. According to certain embodiments, the anionic surfactant of the present invention preferably comprises one or more alkyl ether sulfates, or mixtures thereof. In certain more preferred embodiments, the anionic surfactant of the present invention comprises sodium trideceth sulfate. Sodium trideceth sulfate is the sodium salt of the sulfated tridecyl alcohol ethoxylate which generally forms the following formula, Ci3H27 (OCH2CH2) nOSO3Na, wherein n has a value between 1 and 4, and is commercially available from Stepan Company of Northfield, Illinois under the trade name, "Cedapal TD-403M". Applicants have discovered that sodium trideceth sulfate can be used for the particular advantage of obtaining compositions having significantly reduced irritation associated therewith according to the present invention. Any amounts of hydrophobically modified materials and suitable anionic surfactants to produce a composition with reduced irritation can be combined in accordance with the present methods. According to certain embodiments, the suitable hydrophobically modified material is used to produce a composition with reduced irritation comprising from greater than zero to about 8% by weight of the hydrophobically modified active material in the composition. Preferably, the suitable hydrophobically modified material is used to produce a composition with reduced irritation comprising from about 0.01 to about 5%, more preferably from about 0.01 to about 4%, even more preferably from about 0.1 to about 4%, and even more preferably from about 0.1 to about 3% hydrophobically modified active material in the composition. The amount of anionic surfactant used in the present invention is preferably a suitable amount to produce a composition with reduced irritation comprising from about 0.1 to about 12.5%, more preferably from about 0.5 to about 8.5%, even more preferably from about 1 to about 8% of the total active anionic surfactant in the composition. In certain preferred embodiments, the amount of active anionic surfactant is a suitable amount to produce a reduced irritation composition comprising from about 3.5 to about 7.3%, more preferably 3.5% or greater than 7.3% or less, more preferably 3.5 % to 7%, and even more preferably from 4% to 7% of the total active anionic surfactant in the composition. The hydrophobically modified material and the anionic surfactant can be combined in accordance with the present invention via any conventional methods for combining two or more fluids. For example, one or more compositions comprising, consisting essentially of, or consisting of at least one hydrophobically modified material and one or more compositions comprising, consisting essentially of, or consisting of at least one anionic surfactant may be combining by pouring, mixing, dropwise addition, pipetting, pumping, and the like, of one of the compositions comprising hydrophobically modified material or anionic surfactant into or with the other in any order using any conventional equipment such as a propellant mechanically agitated by pallet, and the like. According to certain embodiments, the combined step comprises combining a composition comprising anionic surfactant within or with a composition comprising hydrophobically modified material. According to certain embodiments, the combined step comprises combining a composition comprising hydrophobically modified material within or with a composition comprising anionic surfactant. Compositions with reduced irritation produced, as well as any of the compositions comprising hydrophobically modified material or anionic surfactant which are combined in the combined step according to the present methods may additionally comprise any of a variety of other components not exclusively including one or more nonionic surfactants, amphoteric, and / or cationic, agents that provide pearlescent appearance or opacifiers, thickening agents, secondary conditioners, humectants, chelating agents, and additives that improve the appearance, feel and fragrance of the compositions, such as dyes, fragrances, preservatives, agents for pH adjustment, and the like. Any of a variety of nonionic surfactants are suitable for use in the present invention. Examples of suitable nonionic surfactants include, but are not limited to, fatty acid alcohol or amide ethoxylates, monoglyceride ethoxylates, ethoxylated alkyl polyglycosides of sorbitan ester, mixtures thereof, and the like. Certain preferred nonionic surfactants include polyoxyethylene polyol ester derivatives, wherein the polyoxyethylene derivative of polyol ester (1) is derived from (a) a fatty acid containing from about 8 to about 22, and preferably from about 10 to about 14 carbon atoms, and (b) a polyol selected from sorbitol, sorbitan, glucose, α-methylglucoside, polyglucose having an average of about 1 to about 3 glucose residues per molecule, glycerin, pentaerythritol, and mixtures thereof. same, (2) contains an average of from about 10 to about 120, and preferably from about 20 to about 80 oxyethylene units; and (3) has an average of about 1 to about 3 fatty acid residues per mole of polyoxyethylene derivative of polyol ester. Examples of such preferred polyoxyethylene polyol ester derivatives include, but are not limited to, PEG-80 sorbitan laurate and Polysorbate 20. PEG-80 sorbitan laurate, which is a sorbitan monoester of ethoxylated lauric acid with an average of about 80 moles of Ethylene oxide is commercially available from ICI Surfactants of Wilmington, Delaware under the trade name, "Atlas G-4280". Polysorbate 20, which is the laurate monoester of a mixture of sorbitol and sorbitol anhydrides fused to approximately 20 moles of ethylene oxide, is commercially available from ICI Surfactants of Wilmington, Delaware under the trade name "Tween 20." Another class of suitable nonionic surfactants includes long chain alkyl glucoside or polyglucosides, which are the condensation products of (a) a long chain alcohol containing from about 6 to about 22, and preferably from about 8 to about 14 carbon atoms, with (b) glucose or a polymer that contains glucose. Preferred alkyl glycosides comprise from about 1 to about 6 glucose residues per alkyl glucoside molecule. A preferred glucoside is decyl glucoside, which is the condensation product of the decyl alcohol with a glucose polymer and is commercially available from Henkel Corporation of Hoboken, New Jersey under the trade name, "Plantaren 2000." As used in the present invention, the term "amphoteric" should mean: 1) molecules that contain both acidic and basic sites such as, for example, an amino acid that contains both amino (basic) and acid functional groups (e.g. carboxylic acid, acids); or 2) zwitterionic molecules which possess both positive and negative charges within the same molecule. The charges of the latter may be either dependent on or independent of the pH, of the composition. Examples of zwitterionic materials include, but are not limited to, alkyl betaines and amidoalkyl betaines. Amphoteric surfactants are described in the present invention without a counter ion. One skilled in the art would readily recognize that under the pH conditions of the compositions of the present invention, the amphoteric surfactants are either electrically neutral by virtue of having positive and negative charge balancing, or have counter ions such as against alkali metal, alkaline torrid, or ammonium ions.

Examples of amphoteric surfactants suitable for use in the present invention include, but are not limited to, amphocarboxylates such as (mono or di) alkylamphoacetates; alkyl betaines; aminoalkyl betaines; amidoalkyl sultaines; amphophosphates; phosphorylated imidazolines such as phosphobetaines and pyrophosphobetaines; carboxyalkyl alkyl polyamines; alkyimino dipropionates; (mono or di) alkylalanoglycinates; (mono or di) alkylamphoprionates; N-alkyl-β-aminopropionic acids; alkylpolyamino carboxylates; and mixtures thereof. Examples of suitable amphocarboxylate compounds include those of the formula: wherein A is an alkyl or alkenyl group having from about 7 to about 21, for example from about 10 to about 16 carbon atoms; x is an integer from about 2 to about 6; R5 is hydrogen or a carboxyalkyl group containing from about 2 to about 3 carbon atoms; R6 is a hydroxyalkyl group containing from about 2 to about 3 carbon atoms or is a group of the formula: wherein Rs is an alkylene group having from about 2 to about 3 carbon atoms and n is 1 or 2; and R is a carboxyalkyl group containing from about 2 to about 3 carbon atoms; Examples of suitable alkyl betaines include those compounds of the formula: BN R (CH2) pC02- wherein B is an alkyl or alkenyl group having from about 8 to about 22, for example, from about 8 to about 16 carbon atoms. carbon; R- and R-io are each independently an alkyl or hydroxyalkyl group having from about 1 to about 4 carbon atoms; and p is 1 or 2. A preferred betaine for use in the present invention is lauryl betaine, commercially available from Albright & Wilson, Ltd. of West Midlands, United Kingdom as "Empigen BB / J." Examples of suitable amidoalkylbetaines include those compounds of the formula: wherein D is an alkyl or alkenyl group having from about 7 to about 21, for example from about 7 to about 15 carbon atoms; R ?? and R-12 are each independently an alkyl or hydroxyalkyl group having from about 1 to about 4 carbon atoms; q is an integer from about 2 to about 6; and m is 1 or 2. An amidoalkyl betaine is cocamidopropyl betaine, commercially available from Goldschmidt Chemical Corporation of Hopewell, Virginia under the trade name, "Tegobetaine L7." Examples of suitable amidoalkyl sultaines include those compounds of the formula B-? C- NH- * ÍCH¿) r * -Nt- "R.Í3-SO3? wherein E is an alkyl or alkenyl group having from about 7 to about 21, for example from about 7 to about 15 carbon atoms; R-14 and R15 are each independently an alkyl, or hydroxyalkyl group having from about 1 to about 4 carbon atoms; r is an integer from about 2 to about 6; and R-13 is an alkylene or hydroxy-alkylene group having from about 2 to about 3 carbon atoms; In one embodiment, the amidoalkyl sultaine is cocamidopropyl hydroxysultaine, commercially available from Rhone-Poulenc Inc. of Cranbury, New Jersey under the trade name, "Mirataine CBS." Examples of suitable amphophosphate compounds include those of the formula: wherein G is an alkyl or alkenyl group having from about 7 to about 21, for example from about 7 to about 15 carbon atoms; s is an integer from about 2 to about 6; R16 is hydrogen or a carboxyalkyl group containing from about 2 to about 3 carbon atoms; R-? is a hydroxyalkyl group that contains approximately 2 to about 3 carbon atoms or a group of the formula: wherein R19 is an alkylene or hydroxy-alkylene group having from about 2 to about 3 carbon atoms and t is 1 or 3; and R-18 is an alkylene or hydroxy-alkylene group having from about 2 to about 3 carbon atoms. In one embodiment, the amphophosphate compounds are sodium lauronide PG-acetate phosphate, commercially available from Mona Industries of Paterson, New Jersey under the trade name, "Monateric 1023," and those described in the U.S. Patent. 4,380,637, which is incorporated herein by reference. Examples of suitable phosphobetaines include those compounds of the formula: Where E, r, R-i, R2 and R3 are as defined above.

In one embodiment, the phosphobetaine compounds are those described in U.S. Pat. Nos. 4,215,064, 4,617,414, and 4,233,192, which are incorporated herein by reference in their entirety. Examples of suitable pyrophosphobetaines include those compounds of the formula: Where E, r, R-i, R2 and R3 are as defined above. In one embodiment, the pyrophosphobetaine compounds are those described in U.S. Pat. Nos. 4,382,036, 4,372,869, and 4,617,414, which are incorporated herein by reference in their entirety. Examples of carboxyalkyl alkyl polyamines include those of the formula: wherein I is an alkyl or alkenyl group containing from about 8 to about 22, for example from about 8 to about 16 carbon atoms; R22 is a carboxyalkyl group having from about 2 to about 3 carbon atoms; R21 is an alkylene group having from about 2 to about 3 carbon atoms and u is an integer from about 1 to about 4. The kinds of cationic surfactants that are suitable for use in this invention include (mono, di, or tri) quaternary alkyls, quaternary benzils, quaternary esters, quaternary ethoxylates, alkyl amines, and mixtures thereof, wherein the alkyl group has from about 6 carbon atoms to about 30 carbon atoms, with from about 8 to about 22 carbon atoms being preferred.

Any of a variety of commercially available pearlescent-looking or opacifying agents which are capable of suspending water-insoluble additives such as silicones and / or which tend to indicate to consumers that the resulting product is a conditioning shampoo are suitable for use in this invention. The agent that provides pearlescent or opacifying appearance may be present in an amount, based on the total weight of the composition, of from about 1 percent to about 10 percent, for example from about 1.5 percent to about 7 percent or from about 2 percent to about 5 percent. Examples of suitable pearlescent-providing agents or opacifiers include, but are not limited to mono or diesters of (a) fatty acids having from about 16 to about 22 carbon atoms and (b) any ethylene or propylene glycol; mono or diesters of (a) fatty acids having from about 16 to about 22 carbon atoms (b) a polyalkylene glycol of the formula: HO- (JO) aH, wherein J is an alkylene group having from about 2 to about 3, carbon atoms; and a is 2 or 3; fatty alcohols containing from about 16 to about 22 carbon atoms; fatty esters of the formula: KCOOCH2L, wherein K and L independently contain from about 15 to about 21 carbon atoms; inorganic solids insoluble in the shampoo composition, and mixtures thereof The agent which provides pearlescent or opacifying appearance may be introduced to the composition for mild cleansing as a pre-formed, stabilized aqueous dispersion, such as that commercially available from Henkel Corporation of Hoboken, New Jersey under the registered name, "Euperlan PK-3000". This material is a combination of glycol distearate (the diester of ethylene glycol and spherical acid), Laureth-4 (CH3 (CH2)? Or CH2 (OCH2CH2) 4OH) and cocamidopropyl betaine and may be in a weight ratio of about 25%. about 30: from about 3 to about 15: from about 20 to about 25, respectively. Any of a variety of commercially available thickeners, which are capable of imparting the proper viscosity to personal cleansing compositions are suitable for use in this invention. If they are used, the thickeners should be present in the shampoo compositions in a suitable amount to raise the Brookfield viscosity of the composition to a value between about 500 to about 10,000 centipoise. Examples of suitable thickening agents do not exclusively include: mono or diesters of 1) polyethylene glycol of formula: HO- (CH2CH2O) zH, wherein z is an integer from about 3 to about 200; and 2) fatty acids containing from about 16 to about 22 carbon atoms; fatty acid esters of ethoxylated polyols; ethoxylates derived from mono and diesters of fatty acids and glycerin; hydroxyalkyl cellulose; alkyl cellulose; hydroxyalkyl alkyl cellulose; and mixtures thereof. Preferred thickeners include polyethylene glycol ester, and more preferably PEG-150 distearate which is available from 'the Stepan Company of Northfield, Illinois or from Comiel, S. p. A. from Bologna, Italy under the trade name, "PEG 6000 DS". Any of a variety of commercially available secondary conditioners, such as volatile silicones, which impart additional attributes, such as, gloss to the hair are suitable for use in this invention. In one embodiment, the volatile silicone conditioning agent has a boiling point at atmospheric pressure less than about 220 ° C. The volatile silicone conditioner may be present in an amount from about 0 percent to about 3 percent, for example from about 0.25 percent to about 2.5 percent or from about 0.5 percent to about 1.0 percent, based on the overall weight of the composition. Examples of suitable volatile silicones do not exclusively include polydimethylsiloxane, polydimethylcyclosiloxane, hexamethyldisiloxane, cyclomethicone fluids such as polydimethylcyclosiloxane commercially available from Dow Corning Corporation of Midland, Michigan under the trade name, "DC-345" and mixtures thereof, and preferably they include cyclomethicone fluids. Any of a variety of commercially available wetting agents, which are capable of providing wetting and conditioning properties to the personal cleansing composition, are suitable for use in the present invention. The humectant may be present in an amount of from about 0 percent to about 10 percent, for example from about 0.5 percent to about 5 percent or from about 0.5 percent to about 3 percent, based on the overall weight of the composition. Examples of suitable humectants do not exclusively include: 1) water-soluble liquid polyols selected from the group comprising glycerin, propylene glycol, hexylene glycol, butylene glycol, dipropylene glycol, and mixtures thereof; 2) polyalkylene glycol of the formula: HO- (R "O) b-H, wherein R" is an alkylene group having from about 2 to about 3 carbon atoms and b is an integer from about 2 to about 10; 3) polyethylene glycol methyl glucose ether of the formula CH 3 -C 6 H 10 O 5 - (OCH 2 CH 2) C-OH, wherein c is an integer from about 5 to about 25; 4) urea; and 5) mixtures thereof, with glycerin being the preferred humectant. Examples of suitable chelating agents include those which are capable of protecting and preserving the compositions of this invention. Preferably, the chelating agent is ethylenediamine tetraacetic acid ("EDTA"), and more preferably is tetrasodium EDTA, commercially available from the Dow Chemical Company of Midland, Michigan under the trade name, "Versen 100XL" and is present in an amount, based on the total weight of the composition, from about 0 to about 0.5 percent or from about 0.05 percent to about 0.25 percent. Suitable preservatives include Quaternium-15, commercially available as "Dowicil 200" from the Dow Chemical Corporation of Midland, Michigan, and are present in the composition in an amount, based on the total weight of the composition, of about 0 to about 0.2 percent or about 0.05 percent to about 0.10 percent. The methods of the present invention may additionally comprise any of a variety of steps for mixing or introducing one or more of the optional components described above in the present invention with or into a composition comprising a hydrophobically modified material and / or a surfactant agent either before, after, or simultaneously with, the combined step described above. Although in certain embodiments, the order of mixing is not critical, it is preferred, in other embodiments, to pre-mix certain components, such as the fragrance and the nonionic surfactant prior to the addition of said components within a composition comprising a hydrophobically modified material and / or a surfactant. The compositions with reduced irritation produced via the present invention are preferably used as or in personal care products such as shampoos, suds, bath solution, gels, lotions, creams, and the like. As discussed above, applicants have unexpectedly discovered that the present methods allow the formulation of such personal care products having reduced irritation to the skin and / or eyes and desirable foaming characteristics. In accordance with other preferred embodiments, the present invention provides methods for cleansing the skin or hair with reduced irritation comprising the step of contacting the skin or hair of a mammal with a composition with reduced irritation comprising an anionic surfactant. and a hydrophobically modified material capable of binding to the anionic surfactant. Any conventional methods for contacting the skin and / or hair of the mammal can be used in accordance with the present invention. In certain preferred embodiments, the step of contacting comprises applying a composition with reduced irritation of the present invention to human skin and / or human hair. The cleaning methods of the present invention may additionally comprise any of a variety of additional, optional steps conventionally associated with cleansing the hair and skin including, for example, foam, rinsing steps, and the like.

EXAMPLES The following Trans-Epithelial Permeability ("TEP") and Tensiometry tests are used in the present methods and in the following examples. In particular, as described above, the PET test is used to determine when a composition is a reduced irritation composition in accordance with the present invention, and the tensiometry test can be used to determine the suitability of a particular hydrophobically modified material for the binding to the surfactant.

Trans-Epithelial Permeability Test ("TEP Test"): The irritation to eyes and / or skin expected for a given formulation is measured according to the Invittox Protocol number 86, the "Trans-Epithelial Permeability Test (TEP). ) "as set forth in the Invittox Protocol Number 86 (May 1994), incorporated herein by reference. In general, the potential eye and / or skin irritation of a product can be assessed by determining its effect on the permeability of a cell layer, as assessed by fluorescein filtration through the layer. Madin-Darby canine kidney cell monolayers (MDCK) were grown to confluence in microporous inserts in a 24-well plate containing medium or pH buffer for assay in the lower wells. The irritation potential of a product is assessed by measuring the damage to the permeability of the barrier in the cell monolayer after a 15-minute exposure to product dilutions. Damage to the barrier was assessed by the amount of sodium fluorescein that has filtered through to the lower well after 30 minutes, as determined spectrophotometrically. The fluorescein filtration is plotted against the concentration of the test material to determine the EC50 (the maximum concentration of the test material that causes 50% filtration of the dye, for example, 50% damage to the permeability of the barrier) . Higher evaluations are indicative of milder formulas. The exposure of a layer of MDCK cells grown on a microporous membrane to a test sample is a model for the first event that occurs when an irritant comes in contact with the eye. In vivo, the outermost layers of the corneal epithelium form a selectively permeable barrier due to the presence of tight junctions between the cells. After exposure to an irritant, the tight junctions separate, thus removing the permeability barrier. The fluid is imbibed into the underlying layers of the epithelium and into the stroma, causing the collagen flakes to separate, resulting in opacity. The TEP assay measures the effect of an irritant on the breaking of tight junctions between cells in a layer of MDCK cells grown in a microporous insert. The damage is evaluated spectrophotometrically, by measuring the amount of marker dye (fluorescein sodium) that is filtered through the cell layer and from the microporous membrane to the lower well.

Test for Tensiometry Titration: A well-known method for measuring the surface tension of surfactant solutions is the plate method of Wilhelmy (Holmberg, K .; Jonsson, B .; Kronberg, B .; Lindman, B. Surfactants and Polymers in Aqueous-Solution, Wiley &Sons, p.347). In the method, a plate was immersed into a liquid and the downward force exerted by the liquid on the plate was measured. The surface tension of the liquid can then be determined based on the force on the plate and the dimensions of the plate. It is also well known that by measuring the surface tension over a range of concentrations the critical micelle concentration (CMC) can then be determined. There are commercially available appliances for the Wilhelmy plate method. In the following examples, a Kruss K12 tensiometer (Kruss USA) was used, Mathews, NC) with a Wilhelmy platinum plate used to determine the surface tension of each sample in a range of concentrations. The test can be carried out either forward or reversed. In any case, a container for the sample contains a certain initial solution in which the Wilhelmy plate measures the surface tension. A second solution is then dosed into the sample container, agitated, and then tested again with the Wilhelmy plate. The solution initially in the container for the sample before starting the titration, within which the second solution is dosed, will be referred to below as the initial solution, and the solution that is dosed into the container for the sample during the titration will be hereinafter referred to as the dosing solution, in accordance with the convention used by Kruss USA. In the forward titration, the concentration of the initial solution is less than the concentration of the dosing solution. In this example during the tests for forward titration, the initial solution was water grade CLAR (Fischer Scientific, NJ), without trideceth sulfate sodium. The dosing solution was a solution of trideceth sulfate sodium and water grade CLAR (Fischer Scientific, NJ) with a concentration of 5750 mg / L of sodium trideceth sulfate. A large storage solution, 4L, of the surfactant dosing solution was previously prepared; Sodium trideceth sulfate (Stepan Company, Northfield, IL) was added to the CLAR grade water (Fischer Scientific, NJ) at a concentration of 5750 mg / L. At the start of the forward titration, 50 ml of the initial solution was added to the sample container. The surface tension of this initial solution was measured, and then a volume of the dosing solution was added to the sample container. The solution was stirred for at least 5 minutes, before the following surface tension measurements were taken. All titrations were carried out from 0 mg / L to at least 3500 mg / L of sodium trideceth sulfate, which are beyond the CMC of all the samples. A test that was performed in accordance with this method is referred to in the present invention subsequently as a test for forward titration by tensiometry. Alternatively in the reverse titration, the concentration of the initial solution is greater than the concentration of the dosing solution. During tests for reverse titration of the following examples, the dosing solution was water grade CLAR (Fischer Scientific, NJ), which had no surfactant, 0 mg / L. The total concentration formulations (e.g., those in Table 1) were diluted with water grade CLAR (Fischer Scientific, NJ) at a dilution of about 5% by weight. This 5% diluted solution was then added to the sample container and was the initial solution. The surface tension of this initial solution was measured, and then a volume of the dosing solution was added to the sample container. The solution was stirred for at least 5 minutes, before the following surface tension measurements were taken. This dosage, stirring, and then measurement was repeated until the dilution reached at least 0.0008%. A test that was carried out in accordance with this method is referred to in the present invention subsequently as a Test for reverse titration by tensiometry. From the raw data of tensiometry, the CMC was determined for each sample in the following manner. First, the equation for a horizontal line was adjusted to the portion of the data at high concentrations, for example, concentrations above the nadir of the graph and within the region where the surface tension is essentially constant, as shown, for example. , in figure 2 as line 21. Subsequently, the equation for a straight line is adjusted to the data at lower concentrations that have a surface tension above the previously derived horizontal line, as shown, for example, in the figure 2 as line 22. The intersection of these two lines / equations 23 was then defined as the CMC for that sample. Figure 3 is an exemplary graph showing two curves of tensiometry data 31 and 32 for a composition comprising a surfactant and hydrophobically modified material (curve 31) and its comparative composition comprising anionic surfactant (curve 32). The CMC for curve 31 is shown at point 33 and the CMC for curve 32 is shown at point 34. The CMC Delta 35 is CMC 33 minus CMC 34.

EXAMPLES 1-4 Preparation of compositions for cleaning The cleaning compositions of Examples 1 to 4 were prepared in accordance with the materials and amounts listed in Table 1: TABLE 1 * "expressed in% p / p The compositions of Table 1 were prepared as follows: Water (50.0 parts) was added to a beaker. The polymer, (PEG 8000 in Example # 1, Poliox WSR 205 in Example # 2, Carbopol ETD 2020 in Example # 3 and Carbopol Aqua SF1 in Example # 4) was added to the water with mixing. The following ingredients were added independently with mixing until each respective resulting mixture was homogeneous: Tegobetaine L7V, Monateric 949 J, Cedepal TD403LD, Glycerin 917, Polymer JR400, Dowicil 200, and Versen 100XL. Then the pH of the resulting solution was adjusted with either a 20% solution of citric acid (example 2) or a 20% solution of sodium hydroxide (examples 1, 3, 4) until a final pH of approximately 6.3 to 6.6. Then the remnant of the water was added.

Comparison of the softness of cleaning compositions: The compositions prepared according to examples 1-4 were evaluated for softness in accordance with the aforementioned TEP test. The results of these tests are listed below in Table 2: TABLE 2 Comparison of softness = Statistically Significantly Different (95% of Cl) This example demonstrates that not all materials are capable of mitigating the skin and eye irritation of a surfactant cleansing composition as well.

EXAMPLES 5-8 Preparation of compositions for titration by tensiometry The compositions of Examples 5 to 9 were prepared in accordance with the materials and amounts listed in Table 3: TABLE 3 * * expressed in% w / w The compositions of Table 3 were prepared as follows: water grade CLAR (50.0 parts) was added to a beaker. The polymer, (PEG 8000 in example # 1, Poiyox WSR 205 in example # 2, Carbopol ETD 2020 in example # 3 and Carbopol Aqua SF1 in example # 4) was added to the water with mixing. Then the pH of the resulting solution was adjusted with a 20% solution of sodium hydroxide (as necessary) until a final pH of about 7.0 was obtained. Then the remnant of the water was added.

Critical micelle concentration values: The compositions prepared according to examples 5-9 were evaluated for critical micelle concentration (CMC) values using the experiment for forward titration by tensiometry. The initial solution was 50 ml of one of examples 5 to 9. The dosing solution was 5750 mg / L of trideceth sulfate sodium in water grade CLAR. 42 doses were previously carried out, which increased the trideceth sodium concentration from 0 mg / L in the initial solution to 3771 mg / L in the final measurement. The results of this test are listed below in Table 4: TABLE 4 Comparison of critical micelle concentration The CMC is the concentration of the surfactant (in this example sodium trideceth sulfate) in which the micelles begin to form. In the concentration of the surfactant below the CMC, there is no surface active agent as free micelles, while at the concentrations above the CMC the free micelles are present in solution. In Example 5, the CMC was measured without any polymer and found to be 125 mg / L. Also shown in Table 4 is the Delta CMC associated with the composition of Example 5 (without additional material). In Example 6, with PEG 8000, the measured CMC was 83, which is below the CMC compared to that in Example 5, only surfactant without polymer. In example 7, the addition of Poliox WSR 205 to the solution resulted in a negligible change in the CMC compared to the solution without additional material, example 5. However the addition of Carbopol ETD 2020 has a significant effect on the CMC, increasing the CMC from 124 mg / L without additional material up to 169 mg / L; this represents the second largest Delta CMC. Example 8, Carbopol SF-1, has the highest CMC, and the highest CMC Delta. This example shows that the addition of certain materials to the solution can change the CMC of the surfactant in solution. An increase in the CMC of the solutions suggests that the start of the formation of free micelles occurs at higher concentrations. In Example 5, free micelles were started to form at 124 mg / L of trideceth sulfate, while in Example 9 the free micelles do not begin to form until they reach 400 mg / L of trideceth sulfate. The inventors believe that the change in the CMC towards a higher concentration with the addition of certain materials (for example, examples 8 and 9) occurs because the surfactant is associated with said material, thus reducing the concentration of the free monomer. The concentration of the free monomer is reduced proportionally to the amount of surfactant associated with the material. The magnitude of the Delta CMC suggests that the amount of surfactant that the material is capable of associating with, or the efficiency of the material in association with the surfactant. The addition of PEG 8000 (example 1 and 6) resulted in the lowest, most irritating PET, and the lowest CMC. The addition of Poliox WSR 205 (example 2 and 7) resulted in the second lowest TEP evaluation, and the second lowest CMC. The addition of Carbopol ETD 2020 (example 3 and 8) resulted in the second highest TEP assessment, and the second largest change in CMC. The addition of Carbopol Aqua SF-1 (example 4 and 9) resulted in the highest TEP evaluation, and the highest change in CMC. Surprisingly, the inventors discovered a relationship / correlation between the magnitude of the CMC change caused by the addition of a material and the softness of the composition. The addition of a material or materials that results in a larger change of the CMC results in an improved softness of the composition. The addition of a material that causes an adequate increase in CMC results in a composition with reduced irritation. In Example 9, the concentration of Carbopol Aqua SF-1 was 500 mg / L, and the CMC was 400 mg / L of sodium trideceth sulfate, while the CMC of trideceth sulfate sodium without SF-1 was 125 mg / L. Therefore, the material of Example 9 associated with 275 mg of sodium trideceth sulfate per 500 mg of material, or 0.183 g of sodium trideceth sulfate per 1.0 g of Aqua SF-1. The efficiency of a material to associate with a surfactant is Delta CMC per mass of the material. A material with greater efficiency will associate more surfactant and will produce a higher Delta CMC.

EXAMPLES 10-15 Preparation of compositions for cleaning The cleaning compositions of Examples 10 to 15 were prepared in accordance with the materials and amounts listed in Table 5.

TABLE 5 * * expressed in% w / w Each of the compositions of Table 5 was prepared independently as follows: Water (50.0 parts) was added to a beaker. For examples 11 to 15, Carbopol Aqua SF-1 was added to the water with mixing. (For example 10, this step was omitted). Then the Atlas G-4280 was added with mixing. For Examples 10-15, the following ingredients were subsequently added independently with mixing until each respective resulting mixture was homogeneous: Tegobetaine L7V, Cedepal TD403LD, Glycerin 917, Polymer JR400, Dowicil 200, and Versen 100XL. The pH of the resulting solution was then adjusted with either a 20% solution of sodium hydroxide or a 20% citric acid solution until a final pH of about 6.3 to 6.6 was obtained. Then the remnant of the water was added. Comparison of the softness of cleaning compositions: The compositions prepared according to examples 10-15 were then evaluated for softness in accordance with the aforementioned TEP test. Table 6 lists the TEP value of the composition of each example: TABLE 6 Comparison of softness As shown in Example 10, the composition containing a relatively high amount of the anionic surfactant (6.0% active) without the Carbopol Aqua SF1 recorded a relatively low TEP value and was therefore considered to be irritating. However, after the addition of the Carbopoi Aqua SF1 as shown in example 11, the PET evaluation was improved. Examples 12 to 15 further showed that as the amount of Carbopol Aqua SF-1 added to the composition was increased, the TEP values for those respective compositions were generally improved concomitantly. Also shown in Table 6 is the TEP Delta evaluation relative to the comparable composition, example 10 (without any Carbopol Aqua SF-1). These examples indicated that the presence of Carbopol Aqua SF1 significantly improved the softness to the skin and eyes of the compositions via the surfactant binding, and that said softness was generally improved as the amount of the copolymer was increased. Most of the increase in the TEP assessment (68%) is presented with the addition of only 0.9% of Carbopol Aqua SF-1, Example 10.

Comparison of the critical micelle concentration of the cleaning compositions: The compositions prepared according to examples 10-15 were then evaluated for the critical micelle concentration in accordance with the aforementioned test for reverse titration by tensiometry. Table 7 lists the CMC values of the composition of each example: TABLE 7 Comparison of critical micelle concentration This series of examples, 10-15 shows that as the amount of Carbopol Aqua SF-1 increases from 0 to 6% (0 to 1.8% active), the Delta CMC increased to the highest values. While not wishing to be bound by any particular theory, the inventors attribute this increase in the Delta CMC that results from increasing the concentration of the Carbopol Aqua SF-1 to the ability of the Carbopol Aqua SF-1 to bind the surfactant. As more Carbopol Aqua SF-1 is added to the composition (from example 10 to 15) more surfactant is bound thereto. Since the surfactant that binds to the Carbopol Aqua SF-1 does not contribute to the concentration of the free monomer, the CMC is changed to higher values. Similarly, as shown in table 6, the softness (TEP values) of the composition generally increases with increasing concentrations of Carbopol Aqua SF-1. Again with Examples 10-15, the inventors found a correlation between the increase in CMC and Delta CMC and the improved smoothness (PET / Delta TEP evaluations) of the composition.

Claims (38)

NOVELTY OF THE INVENTION CLAIMS

1. A method for reducing irritation associated with a personal care composition comprising at least one anionic surfactant, the method comprising combining a hydrophobically modified material capable of binding a surfactant with at least one anionic surfactant to produce a composition for care personal with reduced irritation comprising from about 3.5 to less than 7.5 percent by weight of anionic surfactant, based on the total weight of the composition with reduced irritation.

2. The method according to claim 1, further characterized in that said composition with reduced irritation has a Delta PET of at least about 0.75.

3. The method according to claim 2, further characterized in that said composition with reduced irritation has a Delta PET of at least about 1.

4. The method according to claim 3, further characterized in that said composition with reduced irritation has a Delta PET of at least approximately 1.2.

5. - The method according to claim 4, further characterized in that said composition with reduced irritation has a Delta PET of at least about 1.8.

6. The method according to claim 1, further characterized in that said composition with reduced irritation has a Delta CMC of at least about 16.

7. The method according to claim 1, further characterized in that said composition with reduced irritation has a Delta CMC of at least about 80.

8. The method according to claim 1, further characterized in that said composition with reduced irritation has a Delta CMC of at least about 300.

9. The method according to claim 1, further characterized in that said hydrophobically modified material is selected from the group consisting of hydrophobically modified acrylic polymers, hydrophobically modified cellulosics, hydrophobically modified starches, and combinations of two or more thereof.

10. The method according to claim 9, further characterized in that said hydrophobically modified material comprises a hydrophobically modified acrylic polymer.

11. The method according to claim 10, further characterized in that said hydrophobically modified acrylic polymer is derived from at least one unsaturated carboxylic acid monomer; at least one hydrophobic monomer; a hydrophobic chain transfer agent comprising one or more alkyl mercaptans, thioesters, amino-mercaptan-containing compounds, peptide fragments, or combinations thereof; an agent for cross-linking; and, optionally, a steric stabilizer; wherein the amount of said unsaturated carboxylic acid monomer is from about 60% to about 98% by weight based on the total weight of said unsaturated monomers and said hydrophobic monomer.

12. The method according to claim 1, further characterized in that said at least one anionic surfactant is selected from the group consisting of alkyl sulfates, alkyl ether sulfates, alkyl monoglyceryl ether sulphates, alkyl sulfonates, alkylaryl sulfonates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkyl sulfosuccinamates, alkyl amidosulfosuccinates, alkyl carboxylates, alkyl amidoetherscarboxylates, alkyl succinates, fatty acyl sarcosinates, fatty acyl amino acids, fatty acyl taurates, sulfoacetates fatty alkyl, alkyl phosphates, and mixtures of two or more thereof.

13. The method according to claim 1, further characterized in that said anionic surfactant comprises one or more alkyl ether sulfates.

14. - The method according to claim 13, further characterized in that said one or more alkyl ether sulfates comprises sodium trideceth sulfate.

15. The method according to claim 1, further characterized in that said composition with reduced irritation comprises from about 3.5 to about 7.3% anionic surfactant.

16. The method according to claim 15, further characterized in that said composition with reduced irritation comprises from about 3.5 to about 7% anionic surfactant.

17. The method according to claim 16, further characterized in that said composition with reduced irritation comprises from about 4 to about 7% anionic surfactant.

18. The method according to claim 1, further characterized in that said composition with reduced irritation further comprises one or more materials selected from the group consisting of nonionic, amphoteric, and cationic surfactants, agents that provide pearly appearance, opacifying agents, thickening agents, secondary conditioners, humectants, chelating agents, colorants, fragrances, preservatives, and agents for pH adjustment.

19. A method for reducing the irritation associated with a personal care composition comprising at least one anionic surfactant, the method comprising combining a hydrophobically modified acrylic polymer capable of binding a surfactant with at least one anionic surfactant to produce a composition for personal care with reduced irritation having a Delta PET of at least about 1.2 and a Delta CMC of at least about 80, said composition with reduced irritation comprising more than about 3.5 to about 7 percent by weight of anionic surfactant, based on the total weight of the composition with reduced irritation, and at least one material selected from the group consisting of nonionic, amphoteric, and cationic surfactants, agents that provide pearlescent appearance, opacifying agents, thickening agents, secondary conditioners, humectants, chelating agents, colorants, fragrances, preservatives, pH adjusting agents, and combinations of two or more thereof.

20. A method for producing a composition having relatively low irritation associated therewith comprising the step of combining a hydrophobically modified material with at least one anionic surfactant to produce a composition comprising from about 3.5 to less than 7.5% by weight of total anionic surfactant and having a TEP value of at least about 1.5.

21- The method according to claim 20, further characterized in that said composition comprises more than about 3.5 to about 5% by weight of anionic surfactant.

22. The method according to claim 21, further characterized in that said composition has a TEP value of at least about 3.5.

23. The method according to claim 22, further characterized in that said composition has a TEP value of at least about 4.

The method according to claim 23, further characterized in that said composition has a TEP value of less about 4. 5.

25.- The method according to claim 20, further characterized in that said composition comprises more than about 5 to less than 7.5% by weight of anionic surfactant.

26. The method according to claim 25, further characterized in that said composition has a TEP value of at least about 2.

27.- The method according to claim 26, further characterized in that said composition has a TEP value of less approximately 2.5.

28. - The method according to claim 27, further characterized in that said composition has a TEP value of at least about 3.

The method according to claim 22, further characterized in that said hydrophobically modified material comprises a hydrophobically modified acrylic polymer. .

The method according to claim 26, further characterized in that said hydrophobically modified material is selected from the group consisting of hydrophobically modified acrylic polymers, hydrophobically modified cellulosics, hydrophobically modified starches, and combinations of two or more thereof. .

31. The method according to claim 30, further characterized in that said hydrophobically modified material comprises a hydrophobically modified acrylic polymer.

32.- The method according to claim 20, further characterized in that said composition has a Delta PET of at least about 1.

33.- The method according to claim 32, further characterized in that said composition has a Delta PET of less approximately1.8.

34. - The method according to claim 32, further characterized in that said composition has a Delta CMC of at least about 16. The method according to claim 34, further characterized in that said composition has a Delta CMC of at least about 300. 36.- A method for cleaning the skin or hair with reduced irritation comprising the step of contacting the skin or hair of a mammal with a composition with reduced irritation produced in accordance with claim 1. 37.- A method for cleaning the skin or hair with reduced irritation comprising the step of contacting the skin or hair of a mammal with a composition with reduced irritation produced in accordance with claim 19. 38.- A method for cleaning skin or hair with reduced irritation comprising the step of contacting the skin or hair of a mammal with a composition ion with reduced irritation produced in accordance with claim 20.