Oil-based solid cosmetic composition

Abstract: An oil-based solid cosmetic composition comprising one or more polyoxyalkylene modified silicones and one or more conventional cosmetically acceptable oils, pigments, paints or a mixture thereof, is provided to give a cosmetic having excellent feel during use and prolonged beautiful make-up appearance.

Description: The present invention relates to an oil-based solid cosmetic composition which provides excellent feel upon use, and beautiful make-up appearance for a prolonged period of time. Conventional oil-based make-up cosmetic compositions, such as lipsticks, eye shadows, eye liners and oil-base foundations have disadvantages such as having a tendency to run or ooze, causing spots on clothing, and deterioration of the fresh make-up's appearance in a short period of time. Several approaches to solving these problems have been proposed. Incorporation of a volatile oil into the makeup has been suggested so that, after application of the cosmetic composition, the oil evaporates leaving the coloring agents and waxes on the skin surface, thus improving the stay of the cosmetic composition. Use of a film-forming agent such as a polymer agent in combination with a volatile oil has also been suggested to improve the stay of the cosmetic composition by forming a polymer film on the skin surface after the composition is applied to the skin and dried. However, incorporation of a volatile oil into a cosmetic composibon is accompanied by a loss in the gloss of the composition over time, which is especially a problem in the case of lipsticks. Additionally, since the volatile oil evaporates over time, the shape of the lipstick becomes thinner, and the stability over time is poor. EP 0 266 921 reports that polyoxyalkylene modified organopolysiloxanes are useful at alleviating skin irritation in compositions used on the human body. EP 374 332 discloses a water-in-oil emulsion type solid cosmetic, which contains 5 % by weight or more of water. JP 2-88513 discloses a cosmetic composition containing ≥ 5 wt.% of water, preferably ≥ 10 wt.%. JP 1-143,812 discloses a cosmetic composition, in which each of the exemplified compositions contains from more than 1 to 5 wt.% water. Accordingly, the object of the present invention is to provide an oil-based solid cosmetic composition which gives excellent feel during use, and prolonged beautiful appearance. This object is achieved by an oil-based solid cosmetic composition as defined in the accompanying claims. Moreover, the invention is directed to a method for applying a cosmetic pigment to lips comprising applying the above described oil-based solid cosmetic composition. The present invention relates to an oil-based solid cosmetic composition which comprises one or more polyoxyalkylene modified organopolysiloxanes and cosmetically acceptable pigments and one or more conventionally cosmetically acceptable oils. The polyoxyalkylene modified organopolysiloxane of the present invention (hereinafter referred to as polyether modified silicones) is a compound represented by one of the following formulas (1) to (4): wherein R 1 to R 26 are the same or different from each other, and independently represent C 1 to C 32 linear or branched alkyl, a hydrogen atom or a phenyl group; R 1' to R 8' are the same or different from each other, and independently represent a C 1 to C 32 linear or branched alkyl group or a hydrogen atom; p, p1, p2 and p3 independently denote a number from 1 to 18; and x, x1, x2, x3, y, y1, y2, y3, m, m1, m2, m3, n, n1 and t are average numbers which make the proportion of the polyoxyalkylene group contained in the molecule from 1 to 50% by weight, preferably from 5 to 40% by weight. Preferred polyether modified silicones (1) to (4) are those which satisfy the following conditions: R 1 to R 26 : C 1 to C 25 linear or branched alkyl, wherein a portion of them may be a hydrogen atom, R 1' to R 8' : a hydrogen atom or C 1 to C 18 linear or branched alkyl, p to p3: 1 to 20, x to x3: 1 to 50, y to y3: 0 to 50, m to m3: 1 to 500, n to n1: 1 to 100, t: 1 to 100. Most preferably the following conditions should be met: R 1 to R 26 : C 1 to C 22 linear or branched alkyl, wherein a portion of them may be a hydrogen atom, R 1' to R 8' : a hydrogen atom, p to p3: 1 to 5, x to x3: 1 to 50, y to y3: 0 to 20, m to m3: 10 to 300, n to n1: 1 to 50, t: 1 to 50. The polyether modified silicones (1) to (4) are commercially available from Nippon Unicar K.K., Shin-estu Kagaku Kogyo K.K., Toray Dowcorning Silicone K.K. or Toshiba Silicone K.K. It is essential that the polyether modified silicone of the present invention contains from 1 to 50% by weight, preferably 5 to 40% by weight, of a polyoxyalkylene group in the molecule in order to achieve excellent feel and prolonged beautiful appearance of the make-up. If the polyoxyalkylene groups are present outside this range, the effects of the invention cannot be obtained. The polyether modified silicones are contained in the cosmetic composition in an amount from 5 to 30% by weight based on the total weight of the composition. It is preferred that the oil-based solid cosmetic compositions according to the present invention contain one or more of the above-described polyether modified silicones, oil ingredients and pigments but be substantially free from water. Thus, it is preferred that the composition of the present invention be a non-aqueous composition. Oil ingredients which may be used in the present invention include solid oils, semi-solid oils and liquid oils, and they may be used in a mixture of two or more. Examples of the solid or semi-solid oils include Japan wax, hydrogenated beef tallow, carnauba wax, candelilla wax, rice wax, beeswax, ceresine wax, microcrystalline wax, paraffin wax, polyethylene wax, hydrogenated jojoba oil, lanolin, and vaseline. The amount of the oil used may be varied depending on the end use of the cosmetic composition, and is in the range from 1 to 90% by weight, preferably from 5 to 70% by weight. Examples of liquid oils which may be used in the composition of the present invention include hydrocarbons such as liquid paraffin, liquid isoparaffin (liquid polyisobutylene) and squalene; animal or vegetable oils of natural origin such as olive oil and jojoba oil; silicone oils such as dimethylpolysiloxane; and synthetic esters such as isopropylmyristate. The amount of the liquid oil ingredient used depends also on the end use desired, and ranges from 1 to 90%, preferably from 5 to 70% by weight based on the total weight of the composition. The pigments used in the present invention are conventional cosmetic pigments. Examples of the pigments include body pigments such as talc, sericite, mica, kaolin, silica, nylon powder, polyethylene powder and cellulose powder; coloring agents such as carbon black, titanium oxide, iron oxide, zinc oxide, ultramarine, prussian blue, chromium oxide, dyestuffs of the organic tar series and lakes; complex pigments such as titanated oxide and iron oxide-coated mica. The particle surface of these pigments may be optionally treated with silicones, higher fatty acids, higher alcohols, aliphatic esters, metallic soaps, amino acids or alkylphosphates. It is preferred that one or more of these pigments be contained in the solid cosmetic compositions of the present invention in an amount from 0.1 to 95%, preferably from 5 to 70% by weight based on the total weight of the composition. The oil-based solid cosmetic composition according to the present invention may optionally contain ingredients other than those described above as long as they do not detrimentally affect the properties of the composition. These optional ingredients include other conventional cosmetically acceptable substances, such as surfactants, pharmaceutically acceptable ingredients, preservatives, antioxidants, moisturizers, UV absorbers and perfumes. The oil-based solid cosmetic composition of the present invention may be prePared by any conventional process, such as by heating, blending or stirring the above described ingredients to form make-up cosmetics such as lipsticks, foundations, eye shadows and eye liners. The polyether modified silicones used in the oil-based solid cosmetic composition of the present invention have a specific chemical structure, and are in a liquid state when water is not present. However, quite surprisingly, the viscosity of the polyether modified silicone rapidly increases when a small amount of water (1 to 20% by weight) is added, and further addition of water eventually causes the polyether modified silicone to acquire a gel state. At this point, no more water can be absorbed. While not wanting to be bound by the mechanism of action of the present invention, the inventors believe that these phenomena help explain the effects of the invention as follows: when the composition is applied to the skin, it can be smoothly extended on the surface of the skin because the viscosity of the composition as manufactured is low. Pigments contained in the composition can therefore be distributed thinly and uniformly over the skin. This provides excellent feel during use and beautiful make-up appearance. After the composition is applied, the polyether modified silicone in the film formed on the skin surface becomes viscous, due to the supply of moisture from the skin or breath of the wearer. This increase in viscosity helps to hold the pigments more securely, thus providing prolonged beautiful appearance. Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified. EXAMPLES Example 1: Lipstick The ingredients, as shown in Table 1, were heated at 80°C, uniformly blended, cast in a mould, and cooled down to prepare lipsticks. A panel consisting of 10 members used the lipsticks and evaluated them according to the following criteria: Criteria : A: Eight members or more out of ten evaluated as good. B: Six to seven members out of ten evaluated as good. C: Four to five members out of ten evaluated as good. D: Three or less members out of ten evaluated as good. Formulation (Parts by weight) Invention Composition Comparative Compositions L-1 L-2 L-3 L-4 Ceresine 10 10 10 10 Paraffin wax 8 8 8 8 Candelilla wax 2 2 2 2 Squalane 25 25 25 25 Castor oil 37 37 37 37 Liquid paraffin 0 10 0 5 Polyisobutylene 0 0 10 5 Polyether modified silicone (Formula (1) where R 1 to R 9 =CH 3 R 1' =H, m=50 10 0 0 0 to 100, n=1 to 5, x=7 to 15, y=0, p=3; polyoxyethylene: 17%, MW = 8000) Titanium oxide 2 2 2 2 Pigment (D&C Red No.6, Cl 15850) 2 2 2 2 Pigment (D&C Red No.7 Ca Lake, Cl 15850) 1 1 1 1 Pigment (FD&C Yellow No.5 Al Lake, Cl 19140) 3 3 3 3 Antioxidant Suitable amount Perfume Suitable amount Items Invention Product Comparative Products L-1 L-2 L-3 L-4 Appearance after application A B B B Leave mark on cups B D D D Color staying power on lips A D C D Difficult in oozing A C B B As Table 2 shows, the lipstick according to the present invention provides excellent make-up appearance, and excellent ratings in the other evaluation areas. Example 2 The general procedure of Example 1 was followed to prepare a lipstick except that a polyether modified silicone of Formula (2) where R 10 to R 14 =CH 3 , R 2' to R 4' = H, m1 = 50 to 100, n1 = 1 to 5, x1=7 to 15, y1 = 1, p1 = 3, with the content of polyoxyethylene being 34% (based on the weight of the polyether modified silicone) and having an average molecular weight of 10,000, was used instead of the polyether modified silicone employed in the invention product L-1. Example 3 The general procedure of Example 1 was followed to prepare a lipstick except that a polyether modified silicone of Formula (1) where R 1 to R 9 = CH 3 , R 1' = H, m = 60 to 90, n = 3 to 8, x = 5 to 10, y = 0, p = 3, with the content of polyoxyethylene being 11% (based on the weight of the polyether modified silicone) and having an average molecular weight of 8,000, was used instead of the polyether modified silicone employed in the invention product L-1. Example 4 The general procedure of Example 1 was followed to prepare a lipstick except that a polyether modified silicone of Formula (1) where R 1 to R 9 = CH 3 , R 1' = H, m = 20 to 70, n = 1 to 5, x = 7 to 15, y = 0, p = 3, with the content of polyoxyethylene being 26% (based on the weight of the polyether modified silicone) and having an average molecular weight of 6,300, was used instead of the polyether modified silicone employed in the invention product L-1. Example 5 The general procedure of Example 1 was followed to prepare a lipstick, except that a polyether modified silicone of Formula (1) where R 1 to R 9 = CH 3 , R 1' = = H, m = 100 to 150, n = 1 to 5, x = 7 to 15, y = 0, p = 3, with the content of polyoxyethylene being 13% (based on the weight of the polyether modified silicone) and having an average molecular weight of 12,500, was used instead of the polyether modified silicone employed in the invention product L-1. The lipsticks prepared in Examples 4 to 7 all provided excellent feel during use, and maintained beautiful make-up appearance for a prolonged period of time.

Claims: An oilbased solid cosmetic composition which comprises A) one or more polyoxyalkylene modified organopolysiloxanes containing from 1 to 50% by weight of a polyoxyalkylene group in the molecule; B) one or more conventional cosmetically acceptable oils; and C) one or more cosmetically acceptable pigments, wherein the composition is substantially free from water; wherein said cosmetic composition is a lipstick, wherein said polyoxyalkylene modified organopolysiloxane is selected from the group consisting of the compounds represented by the following formulas (1) to (4): wherein R 1 to R 26 are the same or different from each other, and independently represent C 1 to C 32 linear or branched alkyl, a hydrogen atom or a phenyl group; R 1' to R 8' are the same or different from each other, and independently represent a C 1 to C 32 linear or branched alkyl group or a hydrogen atom; p, p1, p2 and p3 independently denote a number of from 1 to 18; and x, x1, x2, x3, y, y1, y2, y3, m, m1, m2, m3, n, n1 and t represent averages which make the proportion of the polyoxyalkylene group contained in the molecule 1 to 50% by weight, based on the total weight of said polyoxyalkylene modified silicone, wherein the content of the one or more polyoxyalkylene modified organopolysiloxanes is 5-30% by weight. The cosmetic composition according to Claim 1, wherein the parameters in formulas (1) to (4) are defined as follows: R 1 to R 26 : C 1 to C 25 linear branched alkyl, wherein a portion of the groups are optionally a hydrogen atom, R 1' to R 8' : Hydrogen atom or C 1 to C 18 linear or branched alkyl, p to p3: to 20, x to x3: 1 to 50, y to y3: 0 to 50, m to m3: 1 to 500, n to n1 : 1 to 100, and t: 1 to 100. The cosmetic composition according to Claim 1, wherein the parameters in formulas (1) to (4) are defined as follows: R 1 to R 26 : C 1 to C 22 linear or branched alkyl, wherein a portion of the groups are optionally a hydrogen atom, R 1' to R 8' : Hydrogen atom, p to p3: 1 to 5, x to x3: 1 to 50, y to y3: 0 to 20, m to m3: 10 to 300, n to n1 : to 50, and t: 1 to 50. A method for applying a cosmetic pigment to lips comprising applying an oilbased solid cosmetic composition according to claim 1.

Inventors: NOJIMA KAZUHIKO, NOJIMA, KAZUHIKO
Applicants: KAO CORP, KAO CORPORATION
Application year: 1992
Main classification: A61K7
IPC codes: A61K8, A61Q1, C08L83