A photoprotective skin cleansing composition

Abstract

The present invention relates to a photoprotective skin cleansing composition, which delivers high protection against UV induced inflammatory and oxidative stress, thereby maintaining or reducing the amount of melanin content on the skin. This ensures the cosmetic benefit of smooth, even and unblemished skin. This is achieved by incorporating specific types of sunscreen compounds of the water-soluble type along with certain skin care actives in a surfactant containing composition.

Description

[0001] P0000831 EP CPL

[0002] 1

[0003] A PHOTOPROTECTIVE SKIN CLEANSING COMPOSITION

[0004] Field of the Invention

[0005] The present invention relates to a photoprotective skin cleansing composition, which delivers high

[0006] 5 protection against UV induced inflammatory and oxidative stress. The invention thus maintains or reduces the amount of melanin content on the skin thereby delivering cosmetic benefit of smooth, even and unblemished skin.

[0007] Background of the Invention

[0008] Solar radiation includes about 5% ultraviolet (UV) radiation, the wavelength of which is between 200 nm and 400 nm. It is further divided into three regions: from 320 to 400 nm (UV-A), 280 to 320 nm (UV-B) and from 200 to 280 nm (UV-C). A substantial portion of UV-C radiation is absorbed by ozone. Scientific studies have indicated that exposure to UV-A and UV-B radiation for short periods causes pigmentation, reddening of the skin and localized irritation; whereas

[0009] 15 continued or prolonged exposure can lead to sunburn, melanoma, formation of wrinkles and age spots. UV radiation is also thought to cause significant damage to hair. Therefore, it is desirable to protect the skin and other keratinous substrates of the human body from the harmful effects of both UV-A and UV-B radiation. This is delivered though cosmetic compositions which provide high SPF (Sun Protection Factor).

[0010] 20

[0011] Various cosmetic preparations are reported for preventing and / or protecting the skin from harmful effects of ultraviolet radiation. Numerous organic sunscreen agents capable of absorbing UV-A rays are reported in the field of cosmetics amongst which a particularly useful sunscreen is t- butylmethoxydibenzoylmethane (also known as Avobenzone and sold as Parsol® 1789). A

[0012] 25 variety of UV-B sunscreens are used in personal care compositions for protection from UV-B radiation. Many cosmetic manufacturers prefer to include UV-A as well as UV-B sunscreens in photoprotective compositions to provide protection over the entire range of UV radiation.

[0013] While high sun protection can be obtained by using leave-on products (e.g. the one described in EP2575748B1), it is a challenge to ensure this from wash-off products. By a leave-on product is meant a composition that one applies on the skin and leaves it thereon to deliver the desired efficacy till the person cleanses that part of the skin (e.g. through a facewash, shower or bath) which is usually several hours or a day later. In contrast, wash-off products are primarily meant for washing or cleaning the skin to make it clean of oils and soil. Wash-off products like soaps,

[0014] 35 face wash, body wash, shampoo etc usually contain high amount of surfactant (generally higher P0000831 EP CPL

[0015] 2 than 3 wt%). Wash-off products are usually used by applying the product diluted with some amount of water on to the skin to generate a lot of lather. The oils and other dirt get trapped in the micelles so formed and the lather along with all the dirt are fully washed away when the skin surface is rinsed with copious amounts of water.

[0016] 5

[0017] Thus, it is rather obvious that much higher amount of sun protection can be obtained from leave- on products than from wash-off products. The efficacy of sun protection from wash-off products will depend on the amount of sunscreen and other actives that remain deposited on the skin after the wash off product has been rinsed free from the skin surface. Thus, deposition of actives like sunscreen are very difficult when delivered through a wash-off product as the primary aim of such products is to maximize removal of material from the surface leaving it visibly clean.

[0018] The present inventors sought to find a solution to this really difficult problem of ensuring that reactive oxygen species formed as a consequence of UV light from sun rays are reduced through

[0019] 15 use of a wash-off product so that problems like irritation due to inflammation of the skin are alleviated. Further UV radiation can cause increase in melanin on the skin leading to unpleasant appearance like dark spots, hyperpigmentation, uneven tanning etc. The present inventors have found a solution to this problem by incorporating specific types of sunscreen compounds of the water-soluble type along with certain skin care actives in a surfactant containing composition.

[0020] 20

[0021] It is thus an object of the present invention to provide for a photoprotective composition which delivers good protection against UV induced inflammation and oxidative stress.

[0022] It is another object of the present invention to provide for photoprotective benefits, while also

[0023] 25 reducing the amount of unpleasant dark spots, hyperpigmentation and uneven skin tone.

[0024] Summary of the Invention

[0025] The first aspect of the present invention relates to a photoprotective skin cleansing composition comprising:

[0026] 30 a) 0.1 to 10 wt% of a water-soluble UVA sunscreen; b) 0.1 to 10 wt% of a water-soluble UVB sunscreen; c) 0.0001 to 5 wt% of a skin care active selected from one or more of vitamin C or its derivative, vitamin E or its derivative, hydroxystearic acid, ketostearic acid, rosmarinic acid and tetrahydroxypropyl ethylenediamine; P0000831 EP CPL

[0027] 3 d) a cosmetically acceptable vehicle comprising 3 to 80 % surfactant by weight of the composition; wherein the solubility in water of said UVA sunscreen and said UVB sunscreen is higher than 10 g / L at 25°C; and

[0028] 5 wherein the composition comprises a mixture of vitamin C, vitamin E and hydroxy stearic acid.

[0029] Another aspect of the present invention relates to a method of delivering photoprotection to skin comprising the steps of washing the skin with a composition of the first aspect, preferably diluted with water followed by rinsing the skin with water.

[0030] Detailed Description of the Invention

[0031] 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

[0032] 15 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. 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

[0033] 20 and 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 x to y", it is understood that

[0034] 25 all ranges combining the different endpoints are also contemplated.

[0035] The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy. Where a feature is disclosed

[0036] 30 with respect to a particular aspect of the invention (for example a method of the invention), such disclosure is also to be considered to apply to any other aspect of the invention (for example a kit of the invention) mutatis mutandis. Preferably, the method or the use is non-therapeutic or cosmetic in nature. P0000831 EP CPL

[0037] 4

[0038] By “a wash-off composition” as used herein, is meant to include a composition for cleaning topical surfaces of mammals, especially humans. This composition is particularly useful for use on the sun-exposed parts of the body. Such a composition is generally of the rinse off type which means that the composition is high in surfactants which are known to help in cleaning surfaces to make

[0039] 5 them free of oils and dirt. The wash-off composition is generally used by diluting with water as it is applied on to skin, scalp or hair, after which the consumer works up a lather to ensure that the dirt and oil on the surface are solubilized in the micelles of the surfactant solution and the body is then rinsed with copious amounts of water to ensure that the surface is substantially free of the composition. Wash off compositions generally comprise at least 3 wt% surfactants.

[0040] “Skin” as used herein is meant to include skin on the face and body (e.g., neck, chest, back, arms, underarms, hands, legs, buttocks and scalp) and especially the sun exposed parts thereof. The wash-off composition of the invention is also of relevance to application on any other keratinous substrates of the human body other than skin e.g. scalp and hair where products may be

[0041] 15 formulated with specific aim of providing photo-protection. It has been observed that with the use of the wash-off composition of the method of the present invention, the dirt and oil on the skin surface are substantially removed during the washing and rinsing process. Further, surprisingly, the specific combination of the sunscreens and the other skin care actives incorporated in the composition ensures that they deposit in much higher amounts than is generally expected from

[0042] 20 rinse off products, in such a way that the deposited ingredients interact synergistically to provide the desired benefit.

[0043] The composition of the invention comprises a water-soluble UVA sunscreen and a water-soluble UVB sunscreen. The preferred UVB sunscreen for use in the wash-off composition is phenyl

[0044] 25 benzimidazole sulphonic acid (PBSA), benzylidene camphor sulfonic acid, or benzophenone- 4, preferably PBSA.

[0045] PBSA has the chemical structure:

[0046] 30 2-Phenylbenzimidazole 5-sulfonic acid P0000831 EP CPL

[0047] 5

[0048] PBSA also known as Ensulizole is commercially available as Eusolex 232 (from Merck KGaA). PBSA is also available under the brand names Neo Heliopan Hydro (from Symrise), Parsol HS (from DSM) and Sunsafe ES (from Uniproma). It is generally used in the water solubilized form after neutralization to deliver desired benefit.

[0049] 5

[0050] Benzylidene camphor sulfonic acid has the chemical structure:

[0051] It is generally used in the water solubilized form pre / post neutralization to deliver the desired

[0052] 10 benefit.

[0053] Benzophenone-4 (Sulisobenzone) has the chemical structure:

[0054] 15 There are certain sunscreens which have both a UVA screening efficacy as well as a UVB screening efficacy. Such sunscreens provide both UVA and UVB protection e.g. benzophenone- 4. Such sunscreens may also be included in the wash-off composition of the invention. When included, it is to be understood that it is taken as having included one type of sunscreen i.e. either a UVA sunscreen or a UVB sunscreen and not both. Thus, when included as a UVA sunscreen, P0000831EP CPL it is essential to include another sunscreen as a UVB sunscreen. Similarly, when included as a UVB sunscreen, it is essential to include another sunscreen as a UVA sunscreen.

[0055] The preferred UVA sunscreen for use in the wash-off composition is one or more of disodium

[0056] 5 phenyl dibenzimidazole tetrasulfonate (Neoheliopan AP) or terephthalylidene dicamphor sulfonic acid (TDSA).

[0057] Di sodium phenyl dibenzimidazole tetra sulfonate also known as bisdisulizole disodium has the chemical structure as given below:

[0058] 10

[0059] This is commercially available as Neo heliopan AP (from Symrise Shanghai Ltd) or as Sunsafe DPDT (from Uniproma). It is generally used in the water solubilized form after neutralization to deliver desired benefit.

[0060] Terephthalylidene dicamphor sulfonic acid (TDSA) has the structure:

[0061] It is also known as Ecamsule. This is commercially available as Mexoryl SX (US4585597) by L’ Oreal or Sunsafe TDSA (from Uniproma). It can be used as parent acid or its salts in water

[0062] 20 solubilized form to deliver the desired benefit. P0000831 EP CPL

[0063] 7

[0064] The wash-off composition preferably comprises 0.1 to 10 wt%, more preferably 0.25 to 8 wt%, even more preferably 0.5 to 5% water-soluble UVA sunscreen. The composition preferably comprises 0.1 to 10 wt%, more preferably 0.25 to 8 wt%, even more preferably 0.5 to 5% water-

[0065] 5 soluble UVB sunscreen.

[0066] The water-soluble sunscreens for inclusion in the wash-off composition of the present invention are generally commercially available in the acid form. When included in the composition in the acid form (pre / partially neutralized forms) i.e. having sulphonic acid group (-SO3H) the wash-off

[0067] 10 composition additionally comprises a neutralising agent to convert the acid form into the salt form, in which form it is known to be active as a sunscreen with an exception to Mexoryl SX which can act as sunscreen with and without neutralization. When included, the neutralising agent is preferably in 0.05% to 4% by weight of the composition. The neutralising agent is preferably an inorganic or an organic alkali. Organic alkali is preferably an amine such as triethanol amine or

[0068] 15 diethanol amine. The present inventors have observed that the inorganic alkali is especially preferred. Preferred are alkali metal hydroxides. Most preferred metal hydroxide for inclusion as neutralising agent in the composition of the invention are sodium hydroxide or potassium hydroxide.

[0069] 20 The composition of the invention includes a skin care active selected from one or more of vitamin C, vitamin E, hydroxystearic acid, ketostearic acid, rosmarinic acid and tetrahydroxypropyl ethylenediamine.

[0070] A preferred skin care active is vitamin C or a derivative thereof. Vitamin C (ascorbic acid,

[0071] 25 ascorbate) is a simple low-molecular-weight carbohydrate that is essential for the body as a water-soluble vitamin. Vitamin C has both oxidized and reduced forms: L-dehydroascorbic and L-ascorbic acid.

[0072] Vitamin C is involved in the formation of the skin barrier and collagen in the dermis and plays a

[0073] 30 physiological role in the skin against antiaging of wrinkles, and in cell signal pathways of cell growth and differentiation, which are related to the occurrence and development of various skin diseases.

[0074] For use in the present invention, vitamin C or its derivative is selected from one or more of

[0075] 35 ascorbic acid, sodium ascorbyl phosphate, 3-0-ethyl ascorbic acid, ascorbyl methylsilanol P0000831EP CPL

[0076] 8 pectinate, magnesium ascorbyl phosphate, ascorbyl glucoside, and tetrahexyldecyl ascorbate; preferably ascorbic acid or sodium ascorbyl phosphate.

[0077] Vitamin C or its derivatives which may be used in the present invention may be one or more of

[0078] 5 the following:

[0079] Sodium ascorbyl phosphate:

[0080] Sodium ascorbyl phosphate is an active stable vitamin C derivative ingredient for the cosmetics industry. It liberates vitamin C in the skin and protects the cells of the skin, promotes collagen formation, and controls the formation of senile keratosis.

[0081] 3-0-Ethyl ascorbic acid:

[0082] 3-0-ethyl ascorbic acid promotes the production of collagen, which significantly improves the structure of the skin cells and the overall condition of skin.

[0083] 15 Ascorbyl methylsilanol pectinate:

[0084] It is known to improve skin texture, as well as helping with reducing aging.

[0085] Magnesium ascorbyl phosphate (MAP):

[0086] Magnesium ascorbyl phosphate (MAP) has all the functions of vitamin C and is very stable. It has

[0087] 20 can effectively resist UV radiation and promotes collagen production. This product is recommended for anti-aging and anti-wrinkle products.

[0088] Ascorbic acid:

[0089] Vitamin C (L-ascorbic acid), USP is an active form of vitamin C as it occurs naturally. It can

[0090] 25 improve appearance of aged and fragile skin.

[0091] Ascorbie Add

[0092] Ascorbyl glucoside: P0000831 EP CPL

[0093] 9

[0094] Ascorbyl glucoside is a water-soluble Vitamin C derivative with superior stability. It resists degradation, and has the same sun protective and anti-aging properties as ascorbic acid.

[0095] Tetrahexyldecyl ascorbate:

[0096] 5 Tetrahexyldecyl ascorbate is a very stable, oil-soluble Vitamin C ester. It has excellent skin penetration and as a result offers increased cell protection against IIV-B radiation. It can improve appearance of aged and fragile skin.

[0097] Aminopropyl ascorbyl phosphate:

[0098] It is a stabilized vitamin C derivative. It is ideal for anti-wrinkle applications.

[0099] When included vitamin C or its derivative is preferably included in an amount of 0.0001 to 2%, more preferably 0.0001 to 1 % by weight of the composition.

[0100] 15 Vitamin E or its derivative is another preferred skin care active for possible inclusion in the composition of the present invention. It is selected from one or more of alpha tocopherol acetate, d-alpha-tocopherol acetate and d-alpha-tocopherol succinate; preferably alpha tocopherol acetate.

[0101] 20 Tocopheryl Acetate or Alpha Tocopheryl Acetate is commonly known as Vitamin E. It has the structure as given below:

[0102] Alpha-tocopheryl acetate, also known as tocopheryl acetate, is a synthetic form of vitamin E. a-

[0103] 25 tocopheryl acetate is a fat-soluble vitamin E and considered the most stable and active form of vitamin E.

[0104] Tocopheryl acetate can be found in many skincare products where it is used as a skinconditioning agent. It helps in preventing skin damages as well as anti-aging and anti-wrinkle products. P0000831 EP CPL

[0105] 10

[0106] D-Alpha tocopherol acetate has the structure as give below:

[0107] 5 d-alpha-Tocopherol acetate is a closely related chemical with alpha-Tocopherol acetate, d- alpha-tocopherol is a natural active ingredient of Vitamin E.

[0108] D alpha tocopherol succinate

[0109] 10 D a-Tocopherol succinate is a fat-soluble vitamin.

[0110] Vitamin E or its derivatives are available from BASF and Matrix Lifescience. BASF markets these materials under the names CopherolR1250 and Vitamin E acetate Care.

[0111] Vitamin E or its derivative when included is preferably present in an amount of 0.0001 to 0.2% by weight of the composition.

[0112] A preferred skin care active for inclusion in the composition of the invention is hydroxy stearic acid (HSA). It is also possible that the HSA is partially or fully neutralised,! i.e it may be present as a

[0113] 20 salt. It is preferred that the hydroxystearic acid is 10- hydroxy stearic acid, 12-hydroxystearic acid or trihydoxystearic acid (e.g. 9,10,13-trihydroxystearic acid) or trihydroxy stearin or compounds that yield one or more molecules of hydroxystearic acid or hydroxystearate on their breakdown like mono, di or tri ester of glycerol with hydroxystearic acid. Of these, hydroxysteric acid is P0000831 EP CPL

[0114] 11 preferably selected from one or more of 12-hydroxystearic acid, 10-hydroxysteric acid, trihydroxystearin, or trihydroxystearic acid; preferably 12-hydroxystearic acid. 12-HSA has the structure as given below:

[0115] 5

[0116] Hydroxystearic acid when used is preferably included in an amount of 0.0001 to 3%, more preferably 0.005 to 2 wt%, further more preferably 0.01 to 1 wt% of the composition.

[0117] The composition of the invention may comprise a skin care active which is ketostearic acid. The

[0118] 10 preferred ketostearic acid for inclusion in the composition of the invention are 7-ketostearic acid, 9-ketostearic acid, 10-ketostearic acid, 12-ketostearic acid or mixtures thereof. The most preferred ketostearic acid is 12-ketostearic acid. Structure of 12-ketostearic acid is given below:

[0119] Ketostearic acid when used is preferably included in an amount of 0.01 to 5 wt%, more preferably 0.1 to 3%, further more preferably 0.1 to 2%, by weight of the composition.

[0120] Yet another skin care active that may be included in the composition of the invention is rosmarinic

[0121] 20 acid or derivative thereof.

[0122] Rosmarinic acid has the chemical formula: P0000831 EP CPL

[0123] 12

[0124] An ester of rosmarinic acid has the formula:

[0125] Where R is a linear or branched aliphatic hydrocarbon having 3 to 24 carbon atoms, preferably 8 to 12 carbon atoms.

[0126] When R is a hydrocarbon with 8 carbon atoms the ester is the ethyl hexyl ester of rosmarinc acid,

[0127] 10 which is a preferred active as per the invention, it has a structure:

[0128] Rosmarinic acid is a phenolic compound commonly occurring in the species of Lamiaceae and 15 Boraginaceae. Rosmarinic acid may be synthetically prepared or may be extracted from natural sources and purified for use in the present invention. Rosmarinic acid, for use in the present invention is preferably extracted from the following plants: Rosmarinus officinalis, Ocimum sanctum, Thymus vulgaris, Melissa officinalis, Salvia officinalis, Anchusa officinalis and Coleus P0000831 EP CPL blumei. The leaves, seeds or roots part of the plant is preferably used for extraction of rosmarinic acid, more preferably the leaf. Of the various plants, Rosmarinus officinalis and Ocimum sanctum are most preferred for extraction of Rosmarinic acid for use in the present invention. When extracted from these plants, Rosmarinic acid is preferably present in an amount of 0.5 to 15%,

[0129] 5 more preferably 0.5 to 5% by weight of the extract. Rosmarinic acid-when used is preferably present in an amount of 0.01 to 2%, preferably 0.05 to 2% by weight of the composition.

[0130] Yet another skin care active that may be included in the composition of the invention is tetrahydroxypropyl ethylenediamine (THPE). THPE has the formula:

[0131] When included, THPE is used in an amount of 0.1 to 4.0%, preferably 0.5 to 2%, by weight of the composition.

[0132] 15

[0133] As per a preferred aspect of the invention, the composition comprises two of said skin care actives. Yet another more preferred aspect relates to inclusion of a combination of three of the skin care actives. An especially preferred aspect relates to inclusion of vitamin C, vitamin E and hydroxystearic acid in the composition of the invention.

[0134] 20

[0135] The composition of the present invention is delivered through a wash off composition which is used for the purpose of cleansing a surface e.g. skin. The 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

[0136] 25 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.

[0137] The wash off compositions of the invention preferably includes a cleansing surfactant. The cleaning surfactant may be one or more of an anionic surfactant, non-ionic or amphoteric

[0138] 30 surfactant. Surfactant may preferably be included in an amount of 3 to 80%, more preferably 6 to 80%, further more preferably 6 to 40%, even further more preferably 6 to 20% by weight of the P0000831 EP CPL

[0139] 14 composition. Anionic surfactant is generally included in an amount of 3.0 to 80 wt%, preferably 4.0 to 40 wt%, more preferably 4.0 to 20 wt%.

[0140] When the wash off composition is in liquid form, it is preferred that the anionic surfactant is a

[0141] 5 soap, an isethionate, taurate, glycinate, glutamate, alkyl sulphate, a-olefin sulphonate, alkyl ether sulphate, succinate, sulphosuccinate, sarcosinate, amphoacetate, and mixtures thereof.

[0142] Preferably, the anionic surfactant is selected from soap, alkyl sulfates, alkyl ether sulfates, isethionate, taurate 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.

[0143] 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.

[0144] 15

[0145] Examples of AES that may be used as 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.

[0146] 20

[0147] 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). Especially suitable is to include them as a surfactant mixture as they have the advantage that they are sulfate-free. Further, they

[0148] 25 offer the ability to formulate isotropic systems at neutral and slightly acidic pH.

[0149] 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. Preferred isethionate sulfonates include cocoyl isethionate and lauroyl isethionate,

[0150] 30 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 alkyl taurate amides include sodium methyl cocoyl taurate and sodium methyl lauroyl taurate. P0000831 EP CPL

[0151] 15

[0152] 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 surfactant 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

[0153] 5 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

[0154] 10 in other desired proportions. Such combination of soap with synthetic surfactants is often called a soap-syndet formulation.

[0155] Preferably, the composition may further comprise an amphoteric surfactant. They provide foam boost and improve sensorial of the composition. Preferably, amphoteric surfactants are selected

[0156] 15 from the class of betaines, sultaines, ethanolamides. Preferred examples are cocamidopropyl betaine (CAPB), cocoamphoacetate and mixtures thereof. When included, the composition preferably comprises from 0.1 to 40 wt%, more preferably 1 to 20 wt%, most preferably from 1 to 5 wt% amphoteric surfactant.

[0157] 20 Non-ionic surfactants may also be included in the wash-off compositions as per the invention. More preferably the nonionic surfactant is selected from those having HLB value in the range 9 to 20. HLB is 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 nonionic surfactant

[0158] 25 having HLB value in the range 9 to 20 is selected from fatty alcohol ethoxylates, alkyl phenol ethoxylates, polyoxyethylene sorbitan alkyl esters and mixtures thereof. Preferably, the composition comprises 0.5 to 5 wt%, more preferably 1 to 4 wt%, even more preferably from 2 to 3 wt% nonionic surfactant having HLB in the range 9 to 20. Another preferred non-ionic surfactant is cocamide monoethanolamide (CMEA).

[0159] 30

[0160] 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). The composition of the invention when in the liquid form preferably comprises 5 to 95 wt%, more

[0161] 35 preferably in 40 to 90 wt% water. P0000831 EP CPL

[0162] 16

[0163] Preferably, the composition further comprises water soluble / dispersible polymers. 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

[0164] 5 5 wt%.

[0165] 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

[0166] 10 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; 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;

[0167] 15 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

[0168] 20 Polyquaternium-24®. 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).

[0169] The composition may further comprise emollients. Examples of emollients that may be used in

[0170] 25 the leave-on composition include stearyl alcohol, glyceryl monoricinoleate, mink oil, isopropyl isostearate, 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, din-butyl sebacate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate, polyethylene glycol, triethylene glycol, lanolin, cocoa

[0171] 30 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 triglyceride, and mixtures thereof.

[0172] 35 P0000831 EP CPL

[0173] 17

[0174] 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.

[0175] 5 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, the soap

[0176] 15 bar may comprises 10 to 50%, more preferably 12 to 40%, further more preferably from 12 to 35% by weight water.

[0177] 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

[0178] 20 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

[0179] 25 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.

[0180] 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 anionic surfactant and amphoteric surfactant. Anionic surfactants preferred are of the amino

[0181] 35 acid class viz. sodium lauroyl glycinate, sodium cocoyl glycinate, sodium lauroyl glutamate, P0000831 EP CPL

[0182] 18 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 compositions additionally usually comprises a humectant selected from glycerol, propylene glycol, dipropylene

[0183] 5 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. Non-ionic surfactants may also be used in self-foaming compositions. A preferred non-ionic surfactant for use in self-foaming composition of the invention is an alkyl glucosides.

[0184] The present invention also relates to a method of delivering photoprotection to skin comprising the steps of washing the skin with a composition of the invention preferably diluted with water

[0185] 15 followed by rinsing the skin with water. The present invention also relates to a method of delivering anti-tanning benefits to skin 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 with water.

[0186] An especially preferred aspect of the invention relates to a method of washing the skin with the

[0187] 20 composition of the invention followed by rinsing the skin with water followed by the step of applying a leave-on sunscreen composition to the skin after said step of rinsing.

[0188] The invention will now be demonstrated with the help of the following non-limiting examples

[0189] 25 Examples

[0190] Examples A-G, 1-4: Effect of combination of sunscreens and a skin care active on UV induced ROS

[0191] Individual actives and various combinations were taken as shown in Table -1 below and the UV induced reactive oxygen species (ROS) generated was measured using the procedure given below:

[0192] Cells (HaCaT) were seeded in 24 well plates and incubated at 37°C in the CO2 incubator for 24 hours and post incubation, cells were exposed to UVAB radiation (100 mJ / cm2) with a minimal level of PBS buffer covering cells and VITRO skin was kept on top of each well of the cell culture

[0193] 35 plate. The VITRO skin washed with placebo cleanser without sunscreens was used for exposure P0000831 EP CPL to UV control cells and skin care active (12HSA, TH PE, Vitamin C and Vitamin E) wells. The VITRO skin washed with sunscreen product was used for exposure to sunscreen group and sunscreen+ skin care active group of wells. One group of cells were not exposed to UV which is control cells / well. After exposure to UV, control cells, UV + Sunscreen cells were replaced with

[0194] 5 fresh media and the remaining wells were treated with respective skin care active for 6 hours. Post incubation of the cell culture plate at 37°C in the CO2 incubator for 6 hours, the cells were washed with PBS buffer and DCFDA reagent containing media was added for 30 minutes. Postincubation media was removed and washed twice with PBS, post washing fresh PBS was added and fluorescence reading was taken at 485 nm (excitation) and 527 nm (emission). The data

[0195] 10 was normalized with total protein and converted into percentages.

[0196] Table - 1

[0197] *The p-value of UV + placebo is compared to the Control sample, while the rest of the p-values are with respect to the UV + placebo sample.

[0198] Sunscreen product in the above table refers to a combination of 3 wt% of phenyl benzimidazole sulfonic acid and 1.2 wt% of disodium phenyl dibenzimidazole tetrasulfonate.

[0199] 20 The data in Table -1 above indicates that a combination of a skin care active with sunscreens (Examples 1 to 4) ensures significant reduction in ROS as compared to ROS generated as a consequence of UV radiation with a single active (Examples C to G). P0000831 EP CPL

[0200] It is to be understood that the experiments described above were conducted under conditions which mimic actual washing scenario, where the concentration of the actives could be an order or two magnitude lower than the concentration claimed in the composition of the present

[0201] 5 invention. This is due to the actual washing condition where the composition is diluted with large amounts of water.

[0202] Examples H, I, 5: Effect of inclusion of skin care actives in a sunscreen containing skin cleansing composition on melanin content:

[0203] 10 A skin cleansing composition as shown in Table -2 was taken and the efficacy in reducing UV- induced melanin synthesis in a 3D tissue model was measured using the procedure as given below:

[0204] Tissues were exposed to LIVAB radiation (750mJ / cm2) using a Solar simulator comprising a Xenon arc lamp, as reguired. Tissues that were not exposed to UV light, were used as control. Before exposure to UV radiation, tissues were washed with respective cleanser products. One set of tissues was washed with cleanser without sunscreens and skin care active and another was washed with sunscreen and skin care active containing cleanser product. After exposure, plates were incubated in 5% CO2 / 37°C incubator. The washing steps and UV exposure were repeated on day 3 and day 5. On day 7 tissues were dissolved in solvable and the melanin

[0205] 20 content was measured at 490nm by TECAN instrument.

[0206] Table -2 P0000831EP CPL

[0207] 21

[0208] The melanin content as measured is summarised in Table -3 below

[0209] Table -3:

[0210] 5 The data in the Table -3 above indicates that a combination of sunscreen and skin care actives in a skin cleansing composition delivers reduction in melanin content on skin.

[0211] Examples 6 -8: SPF delivered by skin cleansing compositions as per the invention Compositions as shown in Table - 4 below were prepared.

[0212] 10

[0213] Table -4 P0000831 EP CPL

[0214] The in vitro SPF values delivered by the above compositions after washing was measured using the procedure as given below:

[0215] A pre-wet vitro skin was applied with diluted wash-off products of Table -4. The vitro skin was

[0216] 5 rinsed off immediately post product application and kept for drying in dark. After the drying, vitro skin was exposed to UV light and transmittance scan was recorded. This scan gives the transmittance as a function of wavelength (290 - 400 nm) for a given sample. For a single vitro skin sample four different spots were scanned. The same was repeated for 3 vitro skin samples. The data reported is thus an average over 12 readings. The reference transmittance scan was obtained using blank vitro skin, with glycerine spread on it as control. The transmittance values were used to arrive at the SPF values using the software provided with the instrument.

[0217] The average in -vitro SPF values delivered by the various samples are summarized in Table -5 below:

[0218] 15

[0219] Table -5

[0220] The data in the table above indicates that very high SPF values are obtained on skin from use of a wash-off compositions of the invention.

[0221] 20

[0222] Examples J-L, 9: Effect of inclusion of three skin care actives as per the invention as compared to including only one active.

[0223] Individual actives and combinations were taken as shown in Table -6 below and the UV induced

[0224] 25 reactive oxygen species (ROS) generated was measured using the procedure given below:

[0225] HaCaT cells were seeded in a 24-well plate and incubated for 24 hours in a CO2 incubator at 37°C. After this initial incubation period, the cells were exposed to UV light at 150 mJ / cm2with PBS buffer. Following the UV exposure, the cells were treated with the actives, both individually

[0226] 30 and in combinations as indicated in the table. After 4 hours of incubation with actives, the cells were washed, and DCFDA reagent in PBS was added. The cells were incubated with the DCFDA P0000831EP CPL

[0227] 23 reagent for 30 minutes. After this incubation, the cells were washed again with PBS, and the ROS levels in the cells were measured at 485 nm for excitation and 535 nm for emission. The readings were then converted into percentages by normalizing them to the untreated cells.

[0228] 5 The data is summarized in Table -6 below:

[0229] Table -6:

[0230] Like the data in Table -2, it is to be understood that the experiments described above were 10 conducted under conditions which mimic actual washing scenario, where the concentration of the actives could be an order or two magnitude lower than the concentration claimed in the composition of the present invention. This is due to the actual washing condition where the composition is diluted with large amounts of water.

[0231] 15 The data is Table -6 above indicates that use of three skin care actives (Example 9) provides for vastly improved reduction in reactive oxygen species as compared to using one active alone (Example L).

Claims

P0000831EP CPL24Claims1 . A photoprotective skin cleansing composition comprising: a) 0.1 to 10 wt% of a water soluble UVA sunscreen; b) 0.1 to 10 wt% of a water soluble UVB sunscreen; c) 0.0001 to 5 wt% of a skin care active selected from one or more of vitamin C or its derivatives, vitamin E or its derivative, hydroxy stearic acid, ketostearic acid, rosmarinic acid and tetrahydroxypropyl ethylenediamine; d) a cosmetically acceptable vehicle comprising 3 to 80% surfactant by weight of the composition; wherein the solubility in water of said UVA sunscreen and said UVB sunscreen is higher than 10 g / L at 25°C; and wherein the composition comprises a mixture of vitamin C, vitamin E and hydroxystearic acid.

2. A composition as claimed in claim 1 wherein the water soluble UVA sunscreen is chosen from di sodium phenyl dibenzimidazole tetra sulfonate, terephthalylidene dicamphor sulfonic acid or mixtures thereof.

3. A composition as claimed in claim 1 or 2 wherein the water soluble UVB sunscreen is selected from phenyl benzimidazole sulphonic acid, benzylidene camphor sulfonic acid, benzophenone-4 and mixtures thereof.

4. A composition as claimed in any one of the preceding claims comprising 0.05 to 4 wt% neutralising agent.

5. A composition as claimed in claim 4 wherein the neutralising agent is an inorganic or organic alkali.

6. A composition as claimed in any one of the preceding claims wherein the hydroxy stearic acid is 12-hydroxystearic acid.

7. A method of delivering photoprotection to skin comprising the steps of washing the skin with a composition as claimed in any one of the preceding claims preferably diluted with water followed by rinsing the skin with water.P0000831EP CPL258. A method as claimed in claim 7 comprising the step of applying a leave-on sunscreen composition to the skin after said step of rinsing.

9. A method of delivering anti-tanning benefits to skin comprising the step of washing the skin with a composition as claimed in any one of the preceding claims 1 to 6 preferably diluted with water followed by the step of rinsing the skin with water.

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