A personal care composition

Abstract

The present invention is in the fields of skin care compositions. There is a need for an improved personal care composition for improving skin health by topical application. The present invention provides a personal care composition comprising a combination of conjugated fatty acid and hydroxy stearic acid in select ratio in a personal care composition. The composition enhances ceramide synthases (CerS) and sphingomyelinase, which thereon improves skin barrier properties by enhanced ceramide synthesis. The present invention further provides a non-therapeutic method for improving barrier properties of skin and a use of a combination of conjugated fatty acid and hydroxy stearic acid for improving barrier properties of skin.

Description

[0001] P0001120EP CPL

[0002] 1

[0003] A PERSONAL CARE COMPOSITION

[0004] Field of the Invention

[0005] The present invention is in the fields of personal care compositions. Particularly it relates 5 to a personal care composition suitable for topical application on skin which improves barrier properties of skin, thereby improving skin health.

[0006] Background of the Invention

[0007] Consumers tend to take care of themselves to maintain a good health. This includes taking care of their body parts, particularly skin, axilla, oral cavity, hair and scalp. Most consumers perceive skin appearance especially face as one of the key indicators of their beauty and health. They desire to have an even skin tone, that includes bright, less or nil hyperpigmentation, free of blemishes. There are factors, like, age, hydration, hormonal changes, acne, and exposure to sunlight and pollution, which may affect the 15 skin tone. Consumers often look for personal care compositions that could reduce such effects and thereby improve skin tone. Further, skin being the outer most layer of human body, it is first line of defence against invading microorganism, such as, virus, fungi and bacteria and prevent infection. Therefore, to be in good health or free of disease, it is preferred to maintain a good skin health. The term ‘good skin health’ herein includes 20 features like, maintaining skin integrity, sufficient moisturisation, good barrier properties and microbiome balance.

[0008] Regarding skin health, ceramides are the building blocks for retaining moisture inside the skin and blocking invading microorganisms. Thus, one of the ways to improve skin 25 health by enhancing ceramide synthesis. It is desired to have a personal care composition, that when applied topically induces such synthesis, thereby boosting skin health.

[0009] In this regard, EP 2752 184 B1 discloses cosmetic compositions comprising a skin 30 lightening additive which is 12-hydroxystearic acid and / or a salt thereof.

[0010] US 2002 / 0068042 A1 discloses a topical composition comprising (a) conjugated linoleic acid, and / or derivatives thereof comprising conjugated linoleic acid moieties, in which at least 1% by weight of the conjugated linoleic acid and / or moieties is present as the transP0001120EP CPL

[0011] 2

[0012] 10, cis 12 isomer, and (b) a dermatologically acceptable carrier. The product is particularly suitable for lightening human skin.

[0013] WO 2018 / 113636 A1 discloses skin lightening additives and personal care compositions 5 containing amino acids and PPAR activating fatty acids compounds. The compositions are useful for attaining even skin colour and reducing pigmentation, age spots and discoloration.

[0014] WO 2016 / 059169 A 1 discloses cosmetic use of topical compositions comprising 10- hydroxystearic acid, a salt or ester thereof for application to human skin for improving condition and appearance of skin.

[0015] WO 2017 / 164681 A1 disclose a cosmetic composition for alleviating atopic dermatitis, containing, as active ingredients, a Lactobacillus rhamnosus culture solution, or a 15 Lactobacillus rhamnosus culture solution and conjugated linoleic acid.

[0016] In spite of the prior art documents, there is still a need for an improved personal care composition for improving skin health by topical application.

[0017] 20 The present inventors have been working in this area, surprising found that a combination of conjugated fatty acid and select hydroxy stearic acid in select amount in a personal care composition enhances ceramide synthases (CerS) and sphingomyelinase, which thereon improves skin barrier properties.

[0018] 25 Summary of the Invention

[0019] Accordingly, in a first aspect, the present invention provides a personal care composition comprising:

[0020] a) 0.001 to 10% by weight of a conjugated fatty acid;

[0021] b) 0.001 to 10% by weight of a hydroxy stearic acid; and

[0022] 30 wherein the ratio of the conjugated fatty acid to the hydroxy stearic acid is in the range 3:1 to 1:3 by weight,

[0023] wherein the hydroxy stearic acid is one or more of 10- hydroxy stearic acid, 12- hydroxystearic acid, or 9,10,13-trihydroxystearic acid.P0001120EP CPL

[0024] 3

[0025] In another aspect, the present invention provides a non-therapeutic method of improving barrier properties of skin comprising steps of:

[0026] a) applying topically a composition according to the first aspect to skin surface; and b) optionally, rinsing the surface.

[0027] 5

[0028] In another aspect, the present invention provides a use of a combination of a conjugated fatty acid and a hydroxy stearic acid in a personal care composition for improving barrier properties of skin.

[0029] 10 Detailed Description of the Invention

[0030] These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. For the avoidance of doubt, any feature of one aspect of the present invention may be utilized in any other aspect of the invention. The word “comprising” is 15 intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight / weight percentages unless otherwise indicated. Except in the operating and 20 comparative examples, or where otherwise explicitly indicated, all numbers in this description and claims indicating amounts of material or conditions of reaction, physical properties of materials and / or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format “from x to y” are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format “from 25 x to y”, it is understood that all ranges combining the different endpoints are also contemplated. Unless specified otherwise, amounts as used herein are expressed in percentage by weight based on total weight of the composition and may be abbreviated as “wt%”.

[0031] 30 “Skin” as used herein is meant to include skin on any part of the body (e.g. face, neck, chest, back, arms, underarms, hands, legs, buttocks and scalp). Preferably, a use, a composition and a method of the present invention is for non-therapeutic use. Any preference described hereinbelow with regard to one aspect of the invention (e.g. a use according to the present invention) is also preferred for use in any one of the other 35 aspects of the invention.P0001120EP CPL

[0032] 4

[0033] It is reported in the arts that ceramide production depends on ceramide synthases (CerS), which typically consists of six members (CerS1-6). Such CerS catalyse the third step of ceramide biosynthesis by acylating sphinganine to dihydroceramide using co5 enzyme A (CoA)-activated fatty acids. Furthermore, CerS also acylate sphingosine formed in the salvage pathway of sphingolipid degradation, leading directly to ceramide production. In similar line, SMPD1 Acid sphingomyelinase is responsible for the conversion of a lipid called sphingomyelin into another type of lipid called ceramide. Sphingomyelin also binds (attaches) to a fat called cholesterol and helps to form other 10 lipids that play roles in various cell processes. The formations of these lipids are critical for the normal structure and function of cells and tissues. Further, ELOVL4 is a protein that also helps in improving skin barrier properties by catalysing the elongation of FAs, such as VLCFA and / or VLCPUFA. Without wishing to bound by theory, it is believed that CerS3, CerS4, SMPD1 and ELOVE4 help in maintaining and / or improving healthy 15 skin barrier and moisturization benefits, which are often relatable to skin barrier properties.

[0034] The composition according to the present invention comprise a conjugated fatty acid and a hydroxy stearic acid. It will be understood that suitable conjugated fatty acid and 20 hydroxy stearic acid include both the acid form and salts thereof.

[0035] Conjugated fatty acid

[0036] The composition comprises a conjugated fatty acid. Preferably the conjugated fatty acid is C8 to C20, more preferably C10 to C20 and most preferably C12 to C18 conjugated 25 fatty acid. Preferably, conjugated fatty acid is selected from CLA (conjugated linoleic acid), CLnA (conjugated linolenic acid), and mixtures thereof. More preferably, CLA is selected as the CFA. Conjugated linoleic acids are mixtures of positional and geometric isomers of polyunsaturated fatty acids with conjugated double bond. Isomers of conjugated linoleic acids include e.g. cis-9, trans-11 conjugated linoleic acid, trans-9, 30 trans-11 conjugated linoleic acid and trans-10, cis-12 conjugated linoleic acid. The most preferred conjugated linoleic acid is cis-9, trans-11 conjugated linoleic acid. Preferably, the conjugated linoleic acid that may be used in the present invention is selected from cis-9, trans-11 conjugated linoleic acid and trans-10, cis-12 conjugated linoleic acid, and mixtures thereof. Preferably, if these two conjugated linoleic acids are used together, 35 then, they may be used in 50:50 ratio.P0001120EP CPL

[0037] 5

[0038] The composition comprises 0.001 to 10% by weight of the conjugated fatty acid. Preferably the composition comprises 0.01 to 5%, more preferably 0.1 to 3%, furthermore preferably 0.25 to 2% by weight of the conjugated fatty acid.

[0039] 5

[0040] Hydroxy stearic acid

[0041] The composition of the invention comprises hydroxy stearic acid. The hydroxy stearic acid is selected from 10-hydroxystearic acid, 12-hydroxystearic acid or tri-hydroxy stearic acid (e.g. 9,10,13-trihydroxystearic acid). It also includes trihydroxy stearin or compounds that yield one or more molecules of hydroxy stearic acid or hydroxy stearate on their breakdown like mono, di or tri ester of glycerol with hydroxy stearic acid. Of these, 10-hydroxystearic acid, 12-hydroxystearic acid and 9,10,13-trihydroxystearic acid are more preferred, 12-hydroxystearic acid (12-HSA) being most preferred. 12-HSA has the structure as given below:

[0042] 15

[0043]

[0044] Hydroxy stearic acid is included in the composition in an amount 0.001 to 10% by weight of the composition. Hydroxy stearic acid is preferably included in 0.01 to 5%, more 20 preferably 0.1 to 3%, furthermore preferably 0.25 to 2% by weight of the composition.

[0045] The ratio of conjugated fatty acid to the hydroxy stearic acid is in the range 3:1 to 1:3 by weight. Preferably the said ratio is in the range 2:1 to 1 :2 by weight and most preferably 1:1 by weight.

[0046] 25

[0047] The composition of the present invention may further comprise a cosmetically acceptable vehicle, which may act as diluents, dispersants, and / or carriers for the actives used in the composition, so as to facilitate their distribution when the composition is applied to the skin. The cosmetically acceptable vehicle suitable for use in the present invention 30 may be aqueous, anhydrous or an emulsion; aqueous or an emulsion, especially water- in-oil or oil-in-water emulsions being most preferred. Water when present typically makes up the balance of the composition. Preferably water is present in a concentrationP0001120EP CPL

[0048] 6

[0049] of 5 to 99%, more preferably from 20 to 80%, still more preferably from 40 and 80% by weight of the composition.

[0050] Leave-on composition

[0051] 5 The composition according to the present invention preferably is delivered as a leave-on composition. The cosmetically acceptable vehicle for a leave-on composition is preferably in the form of an oil, liquid, stick, cream, lotion, spray or gel. The cosmetically acceptable vehicle in leave-on compositions preferably includes ingredients like a nonionic surfactant, a fatty acid, a soap, a polymer, an emollient, a polyhydric alcohol, a 10 solvent, a powder or combinations thereof. Details on the various possible ingredients for inclusion in the cosmetically acceptable vehicle are given below.

[0052] Preferably, the composition comprises a non-ionic surfactant. More preferably the nonionic surfactant is selected from those having HLB value in the range 9 to 20. HLB is 15 calculated using the Griffin method wherein HLB = 20 x Mh / M wherein Mh is the molecular mass of the hydrophilic portion of the molecule and M is the molecular mass of the whole molecule, giving a result on an arbitrary scale of 0 to 20. Preferably, the non-ionic surfactant having HLB value in the range 9 to 20 is selected from fatty alcohol ethoxylates, alkyl phenol ethoxylates, polyoxyethylene sorbitan alkyl esters, and 20 mixtures thereof. Another preferred non-ionic surfactant is cocamide monoethanolamide (CMEA). Preferably, the leave-on composition comprises 0.5 to 5% by weight, more preferably 1 to 4% by weight, even more preferably from 2 to 3% by weight non-ionic surfactant having HLB in the range 9 to 20.

[0053] 25 The composition may further comprise anionic surfactant. Examples of anionic surfactants suitable for the invention include alkyl ether sulphate and sulfonates, alkyl sulphate and sulphonate, alkylbenzene sulphonates, alkyl and di-alkyl sulphosuccinate, C8 to C20 acyl isethionate, 08-020 alkyl ether phosphate, alkyl ether carboxylate, and combinations thereof.

[0054] 30

[0055] The composition may contain a cationic surfactant. Examples of suitable cationic surfactants include palmitamidopropyltrimonium chloride, di-stearyl dimonium chloride, and mixtures thereof. Useful amphoteric surfactants which may be added in the composition include cocoamidopropyl betaine, C12-C20 trialkyl betaines, sodium 35 lauroamphoacetate, and sodium laurodiamphoacetate, or a mixture thereof.P0001120EP CPL

[0056] 7

[0057] Preferably, the composition according to the present invention is delivered in the form of a vanishing cream. A vanishing cream is one which when applied and rubbed on to the human skin, vanishes on the skin leaving behind no significant streaks of the 5 composition. Fatty acids when present in a composition along with a soap provides the so-called vanishing cream effect. Preferably, the leave-on composition comprises fatty acids having 10 to 30, more preferably 12 to 25, even more preferably 14 to 20, furthermore preferably 16 to 18 carbon atoms. Examples of fatty acids that may be used in the composition include pelargonic, lauric, myristic, palmitic, stearic, iso-stearic, oleic, linoleic, arachidic, behenic, erucic acid, and mixtures thereof. Preferably, the fatty acid that may be used is stearic acid or palmitic acid or a mixture thereof. The fatty acid in the present invention is preferably hysteric acid which is substantially (generally about 90 to 95% by weight) a mixture of stearic acid and palmitic acid in a ratio of between 55:45 to 45:55.

[0058] 15

[0059] Preferably, the vanishing cream composition comprises from 2.25 to 25 % by weight, more preferably from 4 to 22 % by weight, even more preferably from 6 to 20 % by weight, furthermore preferably from 8 to 19 % by weight and still more preferably from 10 to 18 % by weight and yet more preferably from 12 to 16 % by weight of the fatty acid.

[0060] 20

[0061] Preferably, the vanishing cream composition comprises soap. Soap, when present in combination with fatty acid in the composition, provides the vanishing effect described above. Preferably, soap in the composition is generally prepared by in situ neutralization of fatty acid that may be present in the composition. Thus, it is preferred that the soap 25 has a carbon chain length that corresponds to the chain length of fatty acid in the composition. The soap is formed from the fatty acid through use of alkali metal hydroxides, e.g. sodium hydroxide or potassium hydroxide. Potassium hydroxide is more preferred. Thus, the soap is preferably a potassium soap (potassium salt of fatty acid). Preferably, the vanishing cream composition comprises from 0.1 to 10% by 30 weight, more preferably from 0.25 to 8% by weight, even more preferably from 0.5 to 7% by weight, furthermore preferably from 0.5 to 5% by weight, even furthermore preferably 0.5 to 3% by weight of soap.P0001120EP CPL

[0062] 8

[0063] Preferably, the leave-on composition may comprise a polymer. The polymer acts as thickener in the composition and improves sensorial properties of the composition. The polymer is preferably selected from the following classes:

[0064] - acrylate I R-methacrylate copolymer e.g. acrylates / steareth-20 methacrylate 5 copolymer (commercially available as Aculyn™ 22) and acrylates / beheneth-25 methacrylate copolymer (commercially available as Aculyn™ 28),

[0065] - acrylate I R-methacrylate crosspolymer e.g. acrylates / steareth-20 methacrylate crosspolymer (commercially available as Aculyn™ 88),

[0066] - acrylates copolymer (commercially available as Aculyn™ 33),

[0067] - acrylate / R-alkyl acrylate crosspolymer e.g. acrylates / C10-C30 alkyl acrylate crosspolymer (commercially available as Pemulen™ TR-2),

[0068] - copolymer of ammonium acryloyldimethyltaurate with vinyl pyrrolidone (commercially available as Aristoflex® AVC),

[0069] - copolymer of sodium acryloyldimethyltaurate with vinyl pyrrolidone (commercially 15 available as Aristoflex® AVS); and

[0070] - crosspolymer of acryloyldimethyltaurate with R-alkyl acrylate and methyacrylate e.g. Ammonium acryloyldimethyltaurate / beheneth-25 methacrylate crosspolymer (commercially available as Aristoflex® HMB and Aristoflex® BLV).

[0071] 20 Preferably, the composition comprises 0.1 to 5% by weight, more preferably 0.25 to 4.5% by weight, even more preferably 0.5 to 4% by weight, furthermore preferably from 0.75 to 3.5% by weight, still more preferably from 0.75 to 2.75 % by weight of the polymer.

[0072] Preferably, the composition comprises emollients. Examples of emollients that may be 25 used in the leave-on composition include stearyl alcohol, glyceryl mono-ricinoleate, mink oil, isopropyl iso-stearate, isobutyl palmitate, iso-cetyl stearate, oleyl alcohol, isopropyl laurate, hexyl laurate, decyl oleate, octadecan-2-ol, iso-cetyl alcohol, eicosanyl alcohol, behenyl alcohol, cetyl palmitate, silicone oils such as dimethylpolysiloxane, din-butyl sebacate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate, polyethylene glycol, triethylene glycol, lanolin, cocoa butter, corn oil, cotton seed oil, olive oil, palm kernel oil, rape seed oil, safflower seed oil, evening primrose oil, soybean oil, sunflower seed oil, avocado oil, sesame seed oil, coconut oil, arachis oil, castor oil, acetylated lanolin alcohols, petroleum jelly, mineral oil, butyl myristate, isopropyl linoleate, lauryl lactate, myristyl lactate, decyl oleate, myristyl myristate, caprylyl 35 triglyceride, and mixtures thereof.P0001120EP CPL

[0073] 9

[0074] Preferably the composition may comprise a polyhydric alcohol. Polyhydric alcohols are selected from one or more of glycerol, propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol, sorbitol, hydroxypropyl sorbitol, hexylene 5 glycol, 1,3-butylene glycol, isoprene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol, or a combination thereof. Most preferred polyhydric alcohol is glycerol.

[0075] Preferably, the composition comprises non-aqueous solvents. Examples of solvents that 10 may be used in the composition include ethyl alcohol, isopropanol, acetone, ethylene glycol ono ethyl ether, diethylene glycol mono butyl ether, diethylene glycol mono ethyl ether, and mixtures thereof.

[0076] Preferably, the composition comprises powders. Examples of powders that may be used 15 in the composition include zinc oxide, titanium oxide, chalk, talc, fullers earth, kaolin, starch, gums, colloidal silica sodium polyacrylate, tetra alkyl and / or trialkyl aryl ammonium smectites, chemically modified magnesium aluminium silicate, organically modified montmorillonite clay, hydrated aluminium silicate, fumed silica, carboxy vinyl polymer, sodium carboxymethyl cellulose, ethylene glycol monostearate, and mixtures 20 thereof.

[0077] The leave-on composition may be in the form of an emulsion, e.g. a water-in-oil emulsion or an oil-in-water emulsion, preferably an oil-in-water emulsion. In such cases, the composition may include mineral oils, silicone oils, and synthetic oils. Amounts of these 25 materials may range from 0.1 to 50% by weight, and preferably, from 0.1 to 30% by weight, and most preferably, from 1 to 20% by weight, including all ranges subsumed therein. Silicone oils may be divided into the volatile and non-volatile varieties. The term “volatile” as used herein refers to those materials which have a measurable vapor pressure at ambient temperature. Volatile silicone oils are preferably chosen from cyclic 30 or linear polydimethylsiloxanes containing from 3 to 9, and preferably, from 4 to 5 silicon atoms. Linear volatile silicone materials generally have viscosities of less than 5 centistokes at 25°C while cyclic materials typically have viscosities of less than 10 centistokes when measured with a Brookfield Viscometer, RV No. 3 spindle at 20 PRM, standardized to mineral oil and at 25°C.

[0078] 35P0001120EP CPL

[0079] 10

[0080] Non-volatile silicone oils useful as carrier material include polyalkyl siloxanes, polyalkylaryl siloxanes and polyether siloxane copolymers. The essentially non-volatile polyalkyl siloxanes useful herein include, for example, polydimethylsiloxanes (like dimethicone, including cross polymers and elastomers) with viscosities of from 5 to 5 100,000 centistokes at 25°C. An often-preferred silicone source is a cyclopentasiloxane and dimethicone solution.

[0081] Water is present in different amounts depending on the type of leave-on composition. Liquid composition may comprise from 10 to 95 % by weight, more preferably 15 to 90% 10 and most preferably 15 to 85% by weight of water. Creams, lotions and gels may comprise lesser amount of water in the range of 5 to 95 % by weight, more preferably 10 to 90% by weight and most preferably 20 to 90% by weight of water. In some scenarios, the composition may comprise 20 to 90% by weight, more preferably 30 to 80% by weight and most preferably 40 to 70% by weight of water.

[0082] 15

[0083] The leave-on composition according to the present invention may be formulated as a sanitizer composition that is intended for providing antimicrobial effect against harmful or potentially harmful microorganisms that may be present on the skin. Sanitizers preferably comprise 40 to 98% by weight, preferably 45 to 95% by weight, preferably 50 20 to 90% by weight, preferably 55 to 85% by weight, preferably 60 to 80% by weight, preferably 65 to 75% by weight, e.g. 70% by weight of C2 to C4 monohydric alcohols wherein said monohydric alcohols are selected from ethanol, isopropyl alcohol, or mixtures thereof. Sanitizer may include certain polyols. Polyols in the composition according to the invention are preferably sorbitol, glycerol, polyethylene glycol, propylene 25 glycol, and combinations thereof. Sanitizers may preferably comprise from 0.01 to 1% by weight of a thickening agent. More preferably the composition comprises 0.05 to 0.8% by weight of a thickening agent, most preferably 0.08 to 0.2% by weight of a thickening agent. Water is generally present in a sanitizer composition from 5 to 40% by weight, preferably 10 to 40% by weight, preferably 12 to 35% by weight, preferably 25 to 30 30% by weight. Sanitizer may preferably comprise one or more fragrance compounds.

[0084] Preferably, the composition comprises a range of other optional ingredients that include antioxidants, binders, buffering agents, colorants, astringents, fragrance, opacifying agents, conditioners, exfoliating agents, pH adjusters, skin sensitizers, skin soothing 35 agents, sunscreens, and skin healing agents.P0001120EP CPL

[0085] 11

[0086] Wash-off compositions

[0087] The composition of the present invention may also be delivered through a wash-off composition. By ‘wash-off’, it is preferably meant that the composition applied on to a 5 surface, e.g. skin, is removed from the surface preferably with water. In other words, the surface is rinsed off with water and the composition so applied is removed. Typically, if the composition is formulated in the form of a wash-off composition, then the composition so applied is removed preferably within 5 minutes, more preferably within 3 minutes, even more preferably within 1 minute and furthermore preferably within 30 seconds, e.g.

[0088] 10 10 or 15 seconds of it being applied on a surface.

[0089] The wash-off compositions of the invention preferably include a surfactant which may be one or more of anionic surfactant, cationic surfactant, non-ionic surfactant or amphoteric surfactant.

[0090] 15

[0091] In the wash-off composition the amount of surfactant varies based on the product format. For example, in a shampoo or wash composition, it preferably comprises the surfactant in an amount from 3 to 80% by weight, preferably 5 to 80% by weight surfactant. Further, if the wash-off composition is formulated as a solid wash-off composition, e.g. a bar, then 20 the composition may comprise preferably from 25 to 70% by weight, preferably from 30 to 65% by weight, preferably from 35 to 60% by weight, preferably from 40 to 55% by weight of surfactant.

[0092] Alternatively, if the wash-off composition is formulated as a liquid wash-off composition, 25 e.g. hand-wash or body-wash composition, then the composition preferably comprises from 3 to 20% by weight, preferably from 5 to 20% by weight, more preferably from 5 to 18% by weight, even more preferably from 5 to 15% by weight, further more preferably from 5 to 14% by weight and still more preferably from 5 to 12% by weight surfactant.

[0093] 30 A suitable anionic surfactant may be selected from a soap and / or a non-soap synthetic anionic surfactant.

[0094] Examples of soap include soaps that may be used as anionic surfactants in a wash-off composition include those formed after saponification of saturated fatty acids having 35 carbon atoms in the range from C8 to C20 with an aqueous alkali e.g. sodium hydroxide,P0001120EP CPL

[0095] 12

[0096] potassium hydroxide and ammonium hydroxide. Typical examples of soap include caprylate (C8), caprates (C10), laurate (C12), myristate (C14), palmitate (C16, stearate (C18) and oleate (C18:1) formed with an aqueous alkali mentioned earlier. Thus, preferred soaps are selected from potassium caprylate, potassium caprate, potassium 5 laurate, potassium myristate, potassium palmitate, potassium stearate, potassium oleate, sodium caprylate, sodium caprate, sodium laurate, sodium myristate, sodium palmitate sodium stearate, sodium oleate, and mixtures thereof. Often, soaps may be present as a mixture of soaps formed from fatty acids of varying chain lengths. Preferably, a non-soap synthetic anionic surfactants is selected from alkyl sulphates, alkyl ether sulphates (AES), alpha olefin sulfonates (AOS), isethionates, taurates, and mixtures thereof.

[0097] When the wash-off composition is in liquid form, it is preferred that the anionic surfactant is a soap, an isethionate, taurate, glycinate, glutamate, alkyl sulphate, a-olefin 15 sulphonate, alkyl ether sulphate, succinate, sulphosuccinate, sarcosinate, amphoacetate, and mixtures thereof.

[0098] Preferably, the anionic surfactant is selected from soap, alkyl sulphates, alkyl ether sulphates, isethionate, taurate, and mixtures thereof. Even more preferably, alkyl ether 20 sulphates are used as the anionic surfactant in the composition. Anionic surfactants are known to provide foam and cleansing action.

[0099] Examples of alkyl sulphates that may be used as anionic surfactant in the composition include sodium lauryl sulphate (SLS), sodium myristyl sulphate, ammonium lauryl 25 sulphate (ALS), sodium pareth sulphate, and mixtures thereof.

[0100] Examples of AES that may be used as non-soap anionic surfactants include anionic surfactants of the general formula:

[0101] 30 R1-(OR’)n-O-SO3- M+,

[0102] wherein:

[0103] R1 is saturated or unsaturated C8-C16, preferably C12-C14 alkyl chain; preferably, R1 is a saturated C8-C16, more preferably a saturated C12-C14 alkyl chain;P0001120EP CPL

[0104] 13

[0105] R’ is ethylene; n is from 1 to 18; preferably from 1 to 15, more preferably from 1 to 10 and even more preferably from 1 to 5,

[0106] M+ is a suitable cation which provides charge neutrality, preferably sodium, calcium, potassium, or magnesium, ammonium, more preferably a sodium cation or ammonium.

[0107] 5

[0108] Examples of AES that may be used as non-soap anionic surfactants in the composition include sodium lauryl ether sulphate (SLES), sodium myristyl ether sulphate and sodium palmityl ether sulphate, ammonium lauryl ether sulphate (ALES), and mixtures thereof. Preferred AES is SLES having 1 to 3 ethylene oxide units per molecule. SLES having 1 10 to 2 ethylene oxide units per molecule is more preferred.

[0109] Another class of anionic surfactants which is particularly desirable are alkyl isethionate (e.g. fatty acid esters of isethionate acid such as sodium lauroyl or sodium cocoyl isethionate) and alkyl taurate (e.g. alkyl taurate amides such as N-methyl taurate).

[0110] 15 Especially suitable is to include them as a surfactant mixture as they have the advantage that they are sulphate-free. Further, they offer the ability to formulate isotropic systems at neutral and slightly acidic pH.

[0111] In a preferred aspect, the present invention relates to a composition comprising 5 to 20% 20 by weight, preferably 6 to 15% by weight of a surfactant system which comprises (a) alkali metal acyl isethionate, (b) alkali metal alkyl taurate. Preferred isethionate sulfonates include cocoyl isethionate and lauroyl isethionate, preferably having sodium or potassium as counterions. The other preferred anionic surfactant for inclusion in the composition of the invention are alkyl taurates, e.g., alkyl taurate amides. Preferably 25 alkyl taurate amides include sodium methyl cocoyl taurate and sodium methyl lauroyl taurate.

[0112] The composition may also be delivered with soap as the anionic surfactant or as a combination of one or more of the above mentioned synthetic anionic surfactants 30 together with soap. Such combination of soap and synthetic anionic surfactants may be included in a cleansing composition in both liquid as well as in solid (e.g. a bar) compositions. The soap for preparing the cleansing composition of the invention is preferably a C8-C24 soap, more preferably C10-C20 soap and most preferably C12-C18 soap. The cation of the soap can be alkali metal, alkaline earth metal or ammonium.

[0113] 35 Preferably, the cation of the soap is selected from sodium, potassium or ammonium.P0001120EP CPL

[0114] 14

[0115] More preferably the cation of the soap is sodium or potassium. Fatty acids derived from other suitable oils / fats such as groundnut, soybean, tallow, palm, palm kernel, etc. may also be used in other desired proportions. Such combination of soap with synthetic surfactants is often called a soap-syndet formulation.

[0116] 5

[0117] Preferably, the composition may further comprise an amphoteric surfactant. They provide foam boost and improve sensorial of the composition. Preferably, amphoteric surfactants are selected from the class of betaines, sultaine, ethanolamide. Preferred examples are cocamidopropyl betaine (CAPB), cocoamphoacetate and mixtures thereof. When included the composition preferably comprises from 0.1 to 40% by weight, more preferably 1 to 20% by weight, most preferably from 1 to 5 %by weight of the amphoteric surfactant.

[0118] Non-ionic surfactants may also be included in the wash-off compositions. Suitable non15 ionic surfactants are the same as those described under the leave-on composition section above. The composition may further comprise an amphoteric surfactant selected from betaines, e.g. cocamidopropyl betaine (CAPB), sulphobetaine, cocoamphoacetate, and mixtures thereof. Most preferred amphoteric surfactant is CAPB. Amphoteric surfactants provide foam boost and improve sensorial properties of the composition. 20

[0119] The pH of the composition is preferably in the range of 4.0 to 10.5, more preferably 4.0 to 9.0. pH as reported in the present invention is measured as follows. The composition is diluted 1:1 with deionized water and pH is directly measured by a standard pH meter at room temperature (25°C).

[0120] 25

[0121] The composition when in the liquid form preferably comprises 5 to 95% by weight, more preferably in 40 to 90% by weight of water. In a liquid wash-off format the composition may comprises water in an amount from 50 to 95% by weight, more preferably from 60 to 90% by weight, even more preferably from 70 to 85% by weight, furthermore preferably from 75 to 80% by weight and still more preferably from 80 to 85% by weight of water.

[0122] Preferably, the composition further comprises water soluble / dispersible polymers. They are known to increase the viscosity and stability of liquid cleansing compositions, to 35 enhance in-use and after-use skin sensory feels, and to enhance lather creaminess andP0001120EP CPL

[0123] 15

[0124] lather stability. Such polymers may preferably be used in amounts from 0.1 to 10% by weight, more preferably from 0.1 to 5% by weight and most preferably 0.1 to 3% by weight of the composition.

[0125] 5 Examples of water soluble / or dispersible polymers include the carbohydrate gums such as cellulose gum, microcrystalline cellulose, cellulose gel, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, sodium carboxymethylcellulose, methyl cellulose, ethyl cellulose, guar gum, gum karaya, gum tragacanth, gum arabic, gum acacia, gum agar, xanthan gum, and mixtures thereof; 10 modified and nonmodified starch granules and pregelatinized cold water soluble starch;

[0126] emulsion polymers such as Aculyn® 28, Aculyn® 22 or Carbopol® Aqua SF1; cationic polymer such as modified polysaccharides including cationic guar available from Rhone Poulenc under the trade name Jaguar® C13S, Jaguar® C14S, Jaguar® C17, or Jaguar® C16; cationic modified cellulose such as LICARE® Polymer JR 30 or JR 40 from 15 Amerchol; N-Hance® 3000, N-Hance® 3196, N-Hance® GPX 215 or N-Hance® GPX 196 from Hercules; synthetic cationic polymer such as Merquat® 100, Merquat® 280, Merquat® 281 and Merquat® 550 sold by Nalco; cationic starches such as StaLok® 100, 200, 300 and 400 sold by Staley Inc.; cationic galactomannans such as Galactasol® 800 series by Henkel, Inc.; Quadrosoft® LM-200; and Polyquaternium-24®. Also suitable are 20 high molecular weight polyethylene glycols such as Polyox® WSR-205 (PEG 14M), Polyox® WSR-N-60K (PEG 45), and Polyox® WSR-301 (PEG 90M).

[0127] The composition may further comprise emollients. Emollients listed above for use in leave-on compositions may be in wash-off compositions also.

[0128] 25

[0129] The compositions may further comprise a wide range of other optional components, e.g. antioxidants, biological additives, buffering agents, colorants, astringents, fragrance, humectants, opacifying agents, conditioners, pH adjusters, skin soothing agents, and skin healing agents.

[0130] 30

[0131] The composition may also be delivered in solid form in which case it is preferably in the form of a bar. In such cases soap bars are preferred. Soap bars generally have the following constitution. Soap i.e., salt of fatty acid is preferably present in an amount of 5 to 80 % by weight, preferably from 10 to 75% by weight, more preferably 25 to 75% by 35 weight of the cleansing composition. It may comprise small amount, about 0.1 to 10%P0001120EP CPL

[0132] 16

[0133] by weight, of synthetic anionic surfactants which could be one or more of the ones listed herein above. The soap bars may include other known ingredients such as perfumes, pigments, preservatives, emollients, gelling agents and thickening agents. Choice of these ingredients will largely depend on the format of the composition. Water is a 5 preferred carrier. When water is present, it is preferably present in at least 1 % by weight, more preferably at least 2% by weight, furthermore preferably at least 5% by weight of the composition. When water is the carrier, soap bar may comprise 10 to 50% by weight, more preferably 12 to 40% by weight, furthermore preferably from 12 to 35% by weight of water.

[0134] 10

[0135] The cleansing composition of the invention may also be delivered through a moisturizing bar composition. Moisturizing bar compositions comprising fatty acyl isethionates, e.g. cocyl isethionate, are especially preferred. Fatty acyl isethionates surfactant “products” are defined as mixtures of anionic acyl isethionate surfactants and fatty acids / fatty acid 15 soaps. They are highly desirable in personal skin or hair cleansing products because they lather well, are mild to the skin and have good emollient properties. Typically, fatty acid isethionate surfactant products are produced by esterification of fatty acids or by reaction of fatty acid chloride having carbon chain length of C8 to C20 with isethionate. A typical surfactant product containing fatty acyl isethionate contains about 40 to 95% 20 by weight acid isethionate, and 5 to 50% by weight, typically 10 to 40% by weight of free fatty acid, may further contain less than 5% by weight, more preferably less than 2% by weight or trace level of other additives. Fatty acid soap may be included in the range of 5 to 15% by weight. Other surfactants like betaines may be included in 1 to 5% by weight. Water is generally included in 2 to 8% by weight of the composition.

[0136] 25

[0137] The composition of the invention may also be delivered through a self-foaming composition. A preferred self-foaming composition comprises 2.5 to 10% by weight surfactant which is usually a mixture of anionic surfactant and amphoteric surfactant. Anionic surfactants preferred are of the amino acid class viz. sodium lauroyl glycinate, 30 sodium cocoyl glycinate, sodium lauroyl glutamate, sodium cocoyl glutamate and may also be selected from one or more of sodium lauroyl isethionate, sodium cocoyl isethionate, alpha olefin sulfonate (AOS), or a combination thereof. The amphoteric surfactant may be one or more as listed herein above. Self-foaming composition additionally usually comprises a humectant selected from glycerol, propylene glycol, 35 dipropylene glycol, polypropylene glycol, polyethylene glycol, sorbitol, hydroxypropylP0001120EP CPL

[0138] 17

[0139] sorbitol, hexylene glycol, 1,3-butylene glycol, isoprene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol, or a combination thereof. It may also comprise an emollient which may be selected from one or more of the compounds listed herein above. Such types of self-foaming compositions are usually free of sulphate. 5

[0140] The composition preferably further comprises preservatives to protect against the growth of potentially harmful microorganisms. Examples of ingredients that may be used as preservatives in the composition include alkyl esters of para hydroxybenzoic acid, hydantoin derivatives, propionate salts, and a variety of quaternary ammonium 10 compounds. More preferably, ingredients that may be used as preservative in the composition are sodium benzoate, iodopropynyl butyl carbamate, methylisothiazolinone, iodopropynylbutylcarbamate, phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate, ethylhexylglycerin, benzyl alcohol, alkane diols, and mixtures thereof. The alkane diols that are suitable for use as preservative 15 are C6-C12 alkanes that are vicinally substituted with hydroxy groups. Illustrative examples include 1,2-octane diol (caprylyl glycol), 2,3-octane diol, 1,2-nonane diol, 1,2- decane diol, 1,2-hexane diol, 3,4-octane diol, mixtures thereof or the like where caprylyl glycol is typically the most preferred. When present in the composition, preservatives are added preferably in an amount 0.001 to 5% by weight, more preferably 0.01 to 3% 20 by weight and most preferably 0.02 to 2% by weight.

[0141] The composition as per the invention may also be delivered through a make-up remover composition. Make-up remover compositions in various forms are known and available like micellar water, lotions, foams, gels, and creams. A preferred make up remover is 25 one which has high amount of oils preferably in the range of 80 to 90% by weight, surfactant, preferably non-ionic, in the range of 5 to 15% by weight, optionally emollients up to 10% by weight and the rest may be water.

[0142] Preferably, the composition further comprises one or more skin brightening agents. Such 30 one or more skin brightening agents may be selected from vitamin B6, vitamin C and its derivatives, vitamin E, glutathione precursors, resorcinol, phenyl ethyl resorcinol, 4-alkyl resorcinol, e.g. 4-ethyl resorcinol, 4-butyl resorcinol, 4-hexyl resorcinol, and mixtures thereof. Alternatively, the one or more skin brightening agents may also be selected from galardin, adapalene, ammonium lactate, arbutin, butyl hydroxy anisole, butyl 35 hydroxy toluene, citrate esters, deoxyarbutin, 1,3-diphenyl propane derivatives, 2,5-P0001120EP CPL

[0143] 18

[0144] dihydroxybenzoic acid and its derivatives, 2-(4-acetoxyphenyl)-1,3-dithiane, 2-(4- hydroxyphenyl)-1,3-dithiane, ellagic acid, glucopyranosyl-1 -ascorbate, gluconic acid, glycolic acid, , 4-Hydroxy-5-methyl-3[2H]-furanone, 4-hydroxyanisole and its derivatives, 4-hydroxybenzoic acid derivatives, hydroxycaprylic acid, inositol ascorbate, linoleic acid, 5 magnesium ascorbyl phosphate, 5-octanoyl salicylic acid, salicylic acid, 3,4,5- trihydroxybenzyl derivatives, acetylglucosamine, pitera extract, symwhite, calcium pantothenate (Melano-block), seppiwhite, and mixtures thereof. Such one or more skin brightening agents may preferably be present in an amount from 0.1 to 10% by weight, more preferably from 1 to 7% by weight and even more preferably from 3 to 5% by 10 weight.

[0145] The composition may comprise an organic sunscreen selected from one or both of a UVA sunscreen and a UVB sunscreen. Sunscreens include those materials commonly employed to block ultraviolet light. Illustrative compounds are the derivatives of PABA, 15 cinnamate and salicylate. For example, avobenzophenone (Parsol 1789®) octyl methoxycinnamate and 2-hydroxy-4-methoxy benzophenone (also known as oxybenzone) can be used. Octyl methoxycinnamate and 2-hydroxy-4-methoxy benzophenone are commercially available under the trademarks, Parsol MCX and Benzophenone-3, respectively. The exact amount of sunscreen employed in the 20 compositions can vary depending upon the degree of protection desired from the sun’s UV radiation. Additives that reflect or scatter the sun rays may also be employed. These additives include oxides like zinc oxide and titanium dioxide.

[0146] There is provided a method of improving barrier properties of skin comprising steps of 25 (a) applying topically the composition according to the present invention on to the skin, and (b) optionally, rinsing the surface. The method is non-therapeutic or cosmetic in nature.

[0147] Step (a) may be carried out simply by taking a suitable amount, for example 5 mL or 2 30 grams, depending on whether the composition is in liquid or solid form, of the composition on hands and gently spreading it over an external surface, e.g. skin. The composition, if required, may also be applied using an applicator in which case, a user is expected to use the applicator to carry out the step of applying the composition; and spread the composition using the applicator on the surface.

[0148] 35P0001120EP CPL

[0149] 19

[0150] If step (b) is carried out, it is preferably be carried out within 5 minutes, more preferably within 4 minutes, even more preferably within 3 minutes, furthermore preferably within 2 minutes and yet more preferably within 1 minute e.g., 30 seconds, or 15 seconds, from carrying outstep (a). Such optional step (b) is particularly required to be carried out within 5 5 minutes, if the composition is formulated into a wash-off type of composition, e.g. a face wash composition. The method is non-therapeutic / cosmetic in nature.

[0151] In another aspect there is provided a use of a combination of a conjugated fatty acid and a hydroxy stearic acid in a personal care composition for improving barrier properties of 10 skin. The use is preferably non-therapeutic or cosmetic in nature. Conjugated fatty acids and hydroxy stearic acids described above are suitable for the use. Most preferred conjugated fatty acid is conjugated linoleic acid.

[0152] Said benefit may be obtained non-therapeutically and by cosmetically applying the 15 composition. It is submitted that improving barrier properties or moisture retention is not necessarily prophylactic. It is submitted that somewhat reduced barrier properties clearly is an inconvenience but does not represent a pathological state. Therefore, this evidently represents a non-prophylactic realisation of the claimed use / method.

[0153] 20 The composition can be in the form of a liquid, lotion, cream, foam, scrub, gel, soap bar or toner, or applied with an implement or via a face mask, pad or patch. Non-limiting examples of such compositions include leave-on skin lotions and creams, shampoos, conditioners, shower gels, toilet bars, antiperspirants, deodorants, depilatories, lipsticks, foundations, mascara, sunless tanners and sunscreen lotions.

[0154] 25

[0155] The invention will now be illustrated with the help of the following non-limiting examples:

[0156] Examples

[0157] HaCaT cells were grown and maintained in high glucose DMEM supplemented with 30 0.03 mM calcium chloride, 1mM sodium pyruvate and 10% FBS (Fetal Bovine Serum) at 37°C with 5% CO2. Later 80% confluent cells were trypsinized and plated in 24 well plates. Post confluency the cells were differentiated for 72 hours by adding differentiation medium containing 2.0 mM calcium chloride. Post differentiation the cells were treated with different concentration and ratios of 12HSA (12 hydroxy stearic acid) and CLA 35 (conjugated linoleic acid). The cells were incubated further for another 24 hrs. At theP0001120EP CPL

[0158] 20

[0159] end of 24 hrs, the entire cells were harvested in tissue lysis buffer and processed further for gene expression studies using KiCqStart® SYBR® Green qPCR ReadyMix™ kit (Sigma). In the process RNA was isolated from the lysates as per the instructions given in the kit. The quality and the quantity of the total RNA isolated and was analysed using 5 2100 Agilent Bioanalyzer (Agilent System). Reverse transcriptions were performed using iScript cDNA synthesis kit (BIO-RAD). Quantitative real time PCR was performed on 7500 fast real time PCR system (Applied Biosystems). Amplification was started at 95°C for 30 seconds as the first step, followed by 40 cycles of qRT-PCR at 95°C for 5 sec, and at 60°C for 20 seconds. mRNA expression was measured in triplicate and was 10 normalized to p-actin expression levels.

[0160] Table 1

[0161]

[0162] From the above table, it is evident that the combination of 12 hydroxy stearic acid and conjugated linoleic acid synergistically improves CERS1, CERS4, EVOLV4 and SMPD1.

[0163] Further, Example 4 in the form of a bodywash composition was prepared following the recipe provided in Table 2.P0001120EP CPL

[0164] 21

[0165] Table 2

[0166]

[0167] It is understood that the experiments described above were conducted in an in vitro assay to evaluate the synergistic antimicrobial behaviour. It is expected that the 5 concentrations to be actually used to prepare a composition for topical use would be vastly different. The concentrations could be orders of magnitude higher due to the following reasons that affect the difference in concentration in the bulk as compared to that at the cellular level. The composition may be formulated as an emulsion or a gel with additional ingredients. The concentration of the desired actives in the oil phase and 10 in the water phase, is expected to be different. They may also have very different physical and hydrodynamic properties like partition coefficients, diffusional rates, convective transport rates and rheological properties. Therefore, it is expected that the concentrations to be used when formulated as a composition would be different from that at the cellular level.

Claims

P0001120EP CPL22Claims:

1. A personal care composition comprising:a) 0.001 to 10% by weight of a conjugated fatty acid;b) 0.001 to 10% by weight of a hydroxy stearic acid; andwherein the ratio of the conjugated fatty acid to the hydroxy stearic acid is in the range 3:1 to 1:3 by weight,wherein the hydroxy stearic acid is one or more of 10- hydroxy stearic acid, 12- hydroxystearic acid, or 9,10,13-trihydroxystearic acid.

2. A composition as claimed in claim 1 wherein the composition comprises 0.01 to 5% by weight of the conjugated fatty acid.

3. A composition as claimed in claim 1 or 2 wherein the conjugated fatty acid is selected from conjugated linoleic acid, conjugated linolenic acid and combinations thereof.

4. A composition as claimed in claim 3 wherein the conjugated fatty acid is conjugated linoleic acid.

5. A composition as claimed in claim 4 wherein the conjugated linoleic acid is conjugated Cis-9, trans-11 conjugated linoleic acid.

6. A composition as claimed in any one of claims 1 to 5 wherein the composition comprises 0.01 to 5% by weight of the hydroxy stearic acid.

7. A composition as claimed in any of claims 1 to 6 wherein the hydroxy stearic acid is 12-hydroxystearic acid.

8. A composition as claimed in any one of claims 1 to 7 wherein the ratio of the conjugated fatty acid to the hydroxy stearic acid is in the range 2:1 to 1 :2 by weight.

9. A composition as claimed in any one of claims 1 to 8 wherein the composition is a leave-on composition which is preferably selected from the group consisting of a lotion, a cream, a spray, a deodorant and a sanitizer.P0001120EP CPL2310. A composition as claimed in any one of claims 1 to 8 wherein the composition is a wash-off composition which is preferably selected from the group consisting of a soap bar, a handwash, a bodywash and a shampoo.

11. A non-therapeutic method of improving barrier properties of skin comprising steps of:a) applying topically a composition as claimed in any one of claims 1 to 10 on to the skin; andb) optionally, rinsing the surface.

12. A use of a combination of a conjugated fatty acid and a hydroxy stearic acid in a personal care composition for enhancing ceramide synthesis in human skin.

13. Use as claimed in claim 12 wherein the conjugated fatty acid is conjugated linoleic acid.

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