A personal cleansing composition

Abstract

The present invention relates to delivering bioactives on to skin through a personal cleansing composition. It more particularly relates to the surprising finding that an active like ketostearic is deposited in much higher amounts as compared to other fatty acids acid of similar type. Unlike those fatty acids, the present invention ensures that there is no compromise on sensory benefit like acceptable viscosity. This is achieved by incorporating ketostearic acid in a cleansing composition comprising a synthetic anionic surfactant.

Description

[0001] A PERSONAL CLEANSING COMPOSITION

[0002] Field of the Invention

[0003] The present invention relates to a delivering bioactives on to skin through a personal cleansing composition. It more particularly relates to the surprising finding that an active like ketostearic is deposited in much higher amounts as compared to other fatty acids acid of similar type. Unlike those fatty acids, the present invention ensures that there is no compromise on sensory benefits like stable and acceptable viscosity.

[0004] Background of the Invention

[0005] Personal cleansing compositions are used to primarily clean topical surfaces of the human and animal body thereby maintaining hygiene. Such composition are delivered in many forms like bars, liquids, gels, and emulsions. Personal cleansing compositions also known as wash-off compositions are used to remove dirt and soil from the skin. It involves applying the composition generally diluted with water on to the skin to generate a foamy liquid. The foamy liquid along with dirt and oil are removed from the skin surface by rinsing with copious amount of water.

[0006] To deliver health benefits to skin, bioactives like vitamins, skin glow agents, sunscreens, immunity benefit agents etc are delivered through leave-on compositions like creams, lotions, gel and ointments. It has always been a challenge to deliver them on to skin through a cleansing composition in sufficient quantities such that they can deliver bioefficacy. This is because wash- off compositions have the primary aim of removal of dirt and oil from the surface. The competing mechanism of deposition of a desired active on the skin surface is therefore a challenge from wash-off compositions. An example is that of a fatty acid like hydroxystearic acid (HSA) which is useful to deposit on skin as it has many useful bioactive properties. The present inventors have found it difficult to deposit HSA in sufficient amounts on to skin through a wash-off composition. Further, HSA is found to thicken the composition undesirably so that it affects the pourability, e.g. it has been found that it is difficult to incorporate bioactively effective amount of 12-HSA (higher than about 0.5%) in a liquid composition without affecting the pourability.

[0007] US2283683 relates to a process for the isolation a purification of long chain aliphatic amino acyl compounds.

[0008] US5464554 relates to a solid detergent composition.

[0009] DE10 2015 213478A1 relates to a stabilizing mixture, i.e. a finely divided dispersion of hydrogenated castor oil in water with anionic, amphoteric and non-ionic surfactants, which is suitable for stabilizing the pearl luster of surfactant agents, in particular cosmetic agents. The present inventors found to their utter surprise that a compound chemically close to HSA viz ketostearic acid (KSA) which is usually present as an impurity (at up to 3 wt% of HSA) during manufacture of HSA does not behave in this way at all. KSA is found to deposit well. Also, they found that KSA can be incorporated in much higher amounts as compared to HSA without impacting the viscosity of the liquid composition i.e it does not thicken as much thereby ensuring good pourability. Other sensorial properties like foaming was also observed to be acceptable.

[0010] It is thus an object of the present invention to ensure high deposition of bioactives from a wash- off composition.

[0011] Summary of the Invention

[0012] The present invention relates to a personal cleansing composition comprising:

[0013] (i) 0.001 to 10.0 wt% ketostearic acid;

[0014] (ii) 3.0 to 80 wt% synthetic anionic surfactant; and

[0015] (iii) 5 to 95 wt% water;

[0016] With the proviso that when the ketostearic acid is in the range of 0.001 to 0.3 wt%, the composition is substantially free of hydroxystearic acid

[0017] Another aspect of the present invention relates to a method of ensuring enhanced deposition of ketostearic acid from a cleansing composition comprising the step of washing the skin with a composition of the present invention preferably diluted with water followed by the step of rinsing the skin with water.

[0018] Detailed Description of the Invention

[0019] Any feature of one aspect of the present invention may be utilized in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of’ or “composed of.” In other words, the listed steps or options need not be exhaustive. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description 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 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%”. The use of any and all examples or exemplary language e.g. “such as” provided herein is intended merely to better illuminate the invention and does not in any way limit the scope of the invention otherwise claimed.

[0020] The composition of the present invention is suitable for the purpose of cleansing a surface e.g. skin. Preferably, the composition is in liquid form. By liquid form is meant a composition that is easily pourable from a bottle with sufficiently high viscosity that sufficient amount e.g. 5 to 10 mL can be poured into a cupped palm. The viscosity is therefore preferably in the range of about 10 to about 20,000 mPa.s. Preferred viscosity is in the range of 1000 to 16000, more preferably in the range of 1000 to 10,000. Viscosity is measured at 25 °C. Viscosity is measured using a Cone / Plate Anton Paar viscometer. The cone used is CP5 which has a diameter of 50 mm and 0.5° angle. The liquid composition may then be applied on to the skin using suitable means, often using hands, and alternatively using a sponge, loofah or similar material along with copious amount of water to create lather; which is rinsed off with water to cleanse the surface, e.g. the skin. "Skin" as used herein is meant to include skin on the face and body e.g., neck, chest, back, arms, underarms, hands, legs and scalp.

[0021] The composition of the invention includes ketostearic acid. The preferred ketostearic acid for inclusion in the composition of the invention are 7-ketostearic acid, 9-ketostearic acid, 10- ketostearic acid, 12-ketostearic acid and mixtures thereof. The most preferred ketostearic acid is 12-ketostearic acid. Structure of 12-ketostearic acid is given below:

[0022] Ketostearic acid is preferably included in 0.001 to 10 wt% by weight of the composition. It is particularly preferred that ketostearic acid is included in at least 0.01 % more preferably at least 0.1%, more preferably at least 0.2% furthermore preferably at least 0.3%, even further more preferably at least 0.5 % and most preferably at least 0.8% by weight of the composition. It is furthermore particularly preferred that ketostearic acid is included in at most 8%, more preferably at most 6%, and even further more preferably at most 5% and most preferably at most 4% by weight of the composition. An especially preferred aspect relates to the composition comprising 0.2 to 4 wt% ketostearic acid.

[0023] When the composition comprises 0.001 to 0.3%, more preferably 0.001 to 0.5%, further more preferably 0.001 to 0.8% ketostearic acid, it is preferred that the composition is substantially free of hydroxystearic acid. It is preferred, that the personal cleansing composition is substantially free of hydroxystearic acid.

[0024] By substantially free of hydroxystearic acid is meant that the amount of hydroxy stearic acid is less than 0.1 wt%, preferably less than 0.01 wt% and ideally absent from the composition. It is especially preferred that if present, hydroxystearic acid is less than the amount of ketostearic acid present. Hydroxystearic acid may be 10-hydroxystearic acid, 12-hydroxystearic acid or trihydoxystearic acid (e.g. 9, 10,13-tri hydroxy stearic acid) or trihydroxy stearin or compounds that yield one or more molecules of hydroxy stearic acid or hydroxystearate on their breakdown like mono, di or tri ester of glycerol with hydroxystearic acid.

[0025] Throughout this specification, any reference to hydroxystearic acid and ketostearic acid, also includes salts or esters thereof. The acids may be partially neutralised and therefore the composition could include a mixture of the acid and its salt, where relevant.

[0026] The composition of the invention also includes a synthetic anionic surfactant in 3.0 to 80 wt%, preferably 4.0 to 40 wt%, more preferably 4.0 to 20 wt%. Preferred synthetic anionic surfactant for inclusion in the composition of the invention are isethionates, taurates, glycinates, alkyl sulfates, alkyl ether sulphates, succinates, sulphosuccinates, amphoacetates, sarconsinates, glutamates, a-olefin sulphonates, lactylates, methyl ester sulfonates and mixtures thereof. It is preferred that the anionic surfactant as per this invention is a synthetic anionic surfactant. Synthetic anionic surfactant as per this invention is an anionic surfactant other then soap.

[0027] Preferably, the synthetic anionic surfactant are selected from isethionates, taurates, glycinates, alkyl sulfates, alkyl ether sulfates (AES), alpha olefin sulfonates (AOS) and mixtures thereof. Even more preferably, alkyl ether sulfates are used as the anionic surfactant in the composition. Anionic surfactants are known to provide foam and cleansing action.

[0028] Examples of alkyl sulfates that may be used as anionic surfactant in the composition include sodium lauryl sulfate (SLS), sodium myristyl sulfate and mixtures thereof. Examples of AES that may be used as a synthetic anionic surfactant include anionic surfactants of the general formula: Ri-(OR’)n-O-SO3' M+, wherein:

[0029] Ri is saturated or unsaturated Cs-Ci6, preferably C12-C14 alkyl chain; preferably, R1 is a saturated Cs-Ci6, more preferably a saturated C12-C14 alkyl chain;

[0030] 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, M+is a suitable cation which provides charge neutrality, preferably ammonium, sodium, calcium, potassium, or magnesium, more preferably a sodium cation.

[0031] Examples of AES that may be used as the synthetic anionic surfactant in the composition include sodium lauryl ether sulfate (SLES), sodium myristyl ether sulfate and sodium palmityl ether sulfate and mixtures thereof. Preferred AES is SLES having 1 to 3 ethylene oxide units per molecule. SLES having 1 to 2 ethylene oxide units per molecule is more preferred.

[0032] Another class of synthetic 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). Especially suitable is to include them as a surfactant mixture as they have the advantage that they are sulfate-free. Further, they offer the ability to formulate systems at neutral and slightly acidic pH.

[0033] As especially preferred aspect relates to compositions comprising 5 to 20%, preferably 6 to 15% by weight of a surfactant system which comprises (a) alkali metal acyl isethionate, (b) alkali metal alkyl taurate.

[0034] Acyl isethionate surfactant is commonly produced by the direct esterification of a fatty acid (e.g., C to Ci6 fatty acid such as lauric acid) and isethionate (e.g., HOCH2CH2SO4M+’ where M+may be, for example, a sodium or potassium counterion) in a process commonly known as the “DEFI” process, where DEFI refers to directly esterified fatty acid isethionate. Preferred isethionate sulfonates include cocoyl isethionate and lauroyl isethionate, preferably having sodium or potassium as counterions.

[0035] The other preferred synthetic anionic surfactant for inclusion in the composition of the invention are alkyl taurates, e.g., alkyl taurate amides. Such alkyl taurate amides may be made by reaction of a taurine; methyl taurine; or a corresponding taurate salt (e.g., NH2CH2CH2SO3 M+, where M+may be sodium or potassium counterion) with the appropriate fatty acid. Preferably alkyl taurate amides include sodium methyl cocoyl taurate and sodium methyl lauroyl taurate.

[0036] The composition may also be delivered with a combination of one or more of the above mentioned synthetic anionic surfactant together with a soap other than salt of HSA or KSA. 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. Preferably, the cation of the soap is selected from sodium, potassium or ammonium. 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. In a soap syndet formulation soap may be included in 0.1 to 30%, preferably from 1 to 25%, further more preferably from 5 to 20 % by weight of the composition.

[0037] Preferably, the composition may further comprise an 0.1 to 40 wt% an amphoteric surfactant, a non-ionic surfactant or mixtures thereof. They provide foam boost and improve sensorial of the composition. Preferably, amphoteric surfactants are selected from the class of betaines, sultaines and amine oxides. Preferred examples are cocamidopropyl betaine (CAPB), cocamide monoethanolamide (CMEA), cocoamphoacetate and mixtures thereof. When included the composition preferably comprises 0.1 to 20 wt%, more preferably from 1 to 10 wt% amphoteric surfactant.

[0038] Suitable nonionic surfactants include addition products of ethylene oxide and / or propylene oxide with fatty alcohols, fatty acids and fatty amines. Any of the alkoxylated materials of the particular type described hereinafter can be used as the nonionic surfactant. Preferably the nonionic surfactant has an HLB of from about 7 to about 20. Non-ionic surfactant of the polyglucoside type may also be used. When included the composition preferably comprises 0.1 to 20 wt%, more preferably from 1 to 10 wt% non-ionic surfactant.

[0039] The pH of the composition is preferably in the range of 4.0 to 10.5, more preferably 4.0 to 7.0. 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).

[0040] The composition of the invention is preferably in the liquid form in which case water is preferably present in 40 to 90 wt%.

[0041] Preferably, the composition further comprises water soluble / dispersible polymers. These polymers can be cationic, anionic, amphoteric or nonionic types with molecular weights higher than 100,000 Dalton. They are known to increase the viscosity and stability of liquid cleansing compositions, to enhance in-use and after-use skin sensory feels, and to enhance lather creaminess and lather stability. Such polymers may preferably be used in amounts from 0.1 to 10 wt%, more preferably from 0.1 to 5 wt%, even more preferably from 0.25 to 3 wt% and further more preferably from 0.5 to 2 wt%

[0042] 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; modified and nonmodified starch granules and pregelatinized cold water soluble starch and phosphate starches; 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 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® and Polyquaternium-67 from Dow. Also suitable are high molecular weight polyethylene glycols such as Polyox® WSR-205 (PEG 14M), Polyox® WSR-N- 60K (PEG 45), and Polyox® WSR-301 (PEG 90M). Polymers that are biodegradable are particularly preferred.

[0043] Preferably, the composition further comprises one or more skin brightening agents. Preferably, the skin brightening agent may be selected from ammonium lactate, arbutin, azelaic acid, kojic acid, butyl hydroxy anisole, butyl hydroxy toluene, citrate esters, 3 diphenyl propane derivatives, ellagic acid, gluco pyranosyl-1 -ascorbate, gluconic acid, hydroquinone, 4 hydroxyanisole, and linoleic acid. The amount of skin brightening agents that may be included in the composition of the invention depends on its efficacy but generally they are included in 0.01 to 5 wt% of the composition.

[0044] Preferably, the composition further comprises preservatives to protect the composition against the growth of potentially harmful microorganisms. Particularly preferred preservatives include hydantoin derivatives, propionate salts, a variety of quaternary ammonium compounds, phenoxyethanol, imidazolidinyl urea, caprylyl glycol, undecyl alanine, capryloyl glycine, sodium dehydroacetate, sodium benzoate and benzyl alcohol. Preservatives are preferably used in amounts ranging from 0.01 wt% to 2 wt% and more preferably from 0.1 to 1 wt%.

[0045] The composition may further comprise emollients, such as stearyl alcohol, glyceryl monoricinoleate, mink oil, cetyl alcohol, isopropyl isostearate, stearic acid, isobutyl palmitate, isocetyl stearate, oleyl alcohol, isopropyl laurate, hexyl laurate, decyl oleate, octadecan-2-ol, isocetyl alcohol, eicosanyl alcohol, behenyl alcohol, cetyl palmitate, silicone oils such as dimethylpolysiloxane, di-n-butyl sebacate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate, polyethylene glycol, triethylene glycol, lanolin, cocoa butter, shea 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, isostearic acid, palmitic acid, isopropyl linoleate, lauryl lactate, myristyl lactate, decyl oleate, myristyl myristate. Emollients may be included in 0.1 to 15 wt% preferably 0.1 to 10 wt% of the composition.

[0046] 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.

[0047] 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 wt%, preferably from 10 to 75%, more preferably 25 to 75% by weight of the cleansing composition. It may comprise small amount (0.1 to 10 wt%) 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 preferred carrier. When water is present, it is preferably present in at least 1 %, more preferably at least 2%, further more preferably at least 5% by weight of the composition. When water is the carrier, soap bar may comprises 10 to 50%, more preferably 12 to 40%, further more preferably from 12 to 35% by weight water.

[0048] 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 (e.g., cocoyl isethionates) surfactant "products" are defined as mixtures of anionic acyl isethionate surfactants and fatty acids / fatty acid 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 wt.% acid isethionate, and 5 to 50 wt.%, typically 10 to 40 wt.% free fatty acid, in addition to isethionate salts, typically at less than 5%, and trace (less than 2 wt.%) of other additives. Fatty acid soap may be included in the range of 5 to 15 wt%. Other surfactants like betaines may be included in 1 to 5 wt%. Water is generally included in 2 to 8 wt% of the composition.

[0049] The composition of the invention may also be delivered through a self-foaming composition. A preferred self-foaming composition comprises 2.5 to 10 wt% surfactant which is usually a mixture of a synthetic anionic surfactant and amphoteric surfactant. Synthetic anionic surfactants preferred are of the amino acid class viz. sodium lauroyl glycinate, 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, dipropylene glycol, polypropylene glycol, polyethylene glycol, sorbitol, hydroxypropyl 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.

[0050] As per another aspect of the present invention there is provided a method of ensuring enhanced deposition of ketostearic acid from a cleansing composition comprising the step of washing the skin with a composition of the invention preferably diluted with water followed by the step of rinsing the skin. The composition may be diluted with water in a weight ratio in the range of 1 :5 to 1 :500 preferably 1 :10 to 1 :100. After the washing step the skin may be rinsed with copious amounts of water to remove substantially all of the composition from the skin surface.

[0051] Yet another aspect of the present invention relates to a composition of the invention for use in depositing ketostearic acid on to skin when the skin is washed with the composition preferably diluted with water followed by rinsing with water. The invention will now be illustrated with the help of the following non-limiting examples.

[0052] Examples

[0053] Examples 1-4: Deposition of 12-KSA as compared to 12-HSA on vitro skin;

[0054] Liquid skin cleansing compositions as shown in Table -1 were prepared.

[0055] Table - 1

[0056] Table - 2:

[0057] The deposition of the actives (12HSA / 12KSA) was measured on vitro skin using the procedure as given below: Vitro skin was taken and cut into 5x5 cm pieces. It was then pre-wet with 500 iL of water and rubbed for 30 seconds. The excess water was then drained. 0.08 ml of the neat product was then applied and lather was generated for 20 seconds. The lather was retained on the vitro skin for 30 seconds. The vitro skin was then rinsed off with 100-120 ml water for 30 seconds. The vitro skin was then extracted with 10 ml methanol by sonicating for 25 minutes. The concentration of the actives in the extract was then measured using LC-MS analysis. The data is summarized in table - 3 below.

[0058] Table - 3

[0059] *The composition was too viscous to be processed easily and so the deposition could not be measured.

[0060] The data in Table - 3 above indicates that 12KSA deposits much better than 12HSA from a composition used to wash the substrate.

[0061] Example 5-7: Rheology of various compositions

[0062] Examples 5-6 as described above was taken. Additionally Example - 7 was prepared with higher amounts of 12KSA. These samples were then taken and the rheology measured at two shear rates (0 s-1and 1 s-1). The procedure used to measure the viscosity at these shear rates is as given below:

[0063] The viscosities of the samples were measured using a Cone / Plate Anton Paar viscometer. The cone used was CP5 which has a diameter of 50 mm and 0.5° angle. The viscosity was measured with a shear ramp in which the samples were subjected to increasing shear rate, and sample viscosity was observed as a function of shear rate. All experiments were conducted at 25°C.

[0064] The data is summarized in table - 4. Table - 4:

[0065] The data in Table -4 above indicates that compositions as per the invention do not thicken undesirably and are within the acceptable viscosity range when increasing amounts of 12KSA are included.

Claims

Claims1. A personal cleansing composition comprising:(i) 0.001 to 10.0 wt% ketostearic acid;(ii) 3.0 to 80 wt% synthetic anionic surfactant; and(iii) 5 to 95 wt% water; with the proviso that when the ketostearic acid is in the range of 0.001 to 0.3 wt%, the composition is substantially free of hydroxystearic acid.

2. A composition as claimed in any one of the preceding claims wherein the composition comprises from 0.2 to 4 wt% ketostearic acid.

3. A composition as claimed in any one of the preceding claims wherein the ketostearic acid is selected from 7-ketostearic acid, 9-ketostearic acid, 10-ketostearic acid, 12-ketostearic acid and mixtures thereof.

4. A composition as claimed in any one of the preceding claims wherein the synthetic anionic surfactant is selected from isethionates, taurates, glycinates, alkyl sulfates, alkyl ether sulphates, succinates, sulphosuccinates, amphoacetates, sarconsinates, glutamates, a- olefin sulphonates, lactylates, methyl ester sulfonates and mixtures thereof.

5. A composition as claimed in any one of the preceding claims further comprising 0.1 to 40 wt% an amphoteric surfactant, non-ionic surfactant or combinations thereof.

6. A composition as claimed in any one of the preceding claims wherein the pH of the composition is in the range 4.0 to 10.5.

7. A composition as claimed in any one of the preceding claims in liquid form.

8. A composition as claimed in claim 7 comprising 40 to 90 wt% water.

9. A composition as claimed in any one of the preceding claims 1 to 6 in solid form preferably in the form of a bar.

10. A composition as claimed in claim 9 comprising 10 to 50 wt% water.

11. A composition as claimed in any one of the preceding claims, wherein the composition is substantially free of hydroxystearic acid.

12. A method of ensuring enhanced deposition of ketostearic acid from a cleansing composition comprising the step of washing the skin with a composition as claimed in any one of the preceding claims preferably diluted with water followed by the step of rinsing the skin with water.

13. Use of a composition as claimed in any one of the preceding claims 1 to 10 for depositing ketostearic acid on to skin when the skin is washed with the composition preferably diluted with water followed by rinsing with water.

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