WO2023118917A1

WO2023118917A1 - Oil-in- water emulsion

Info

Publication number: WO2023118917A1
Application number: PCT/IB2021/000915
Authority: WO
Inventors: Mashiro KIKUCHI; Mai OZAWA
Original assignee: L V M H Recherche
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2023-06-29

Abstract

An oil-in-water emulsion comprising; (A) a polysaccharide having a main chain containing a structural unit in which glucose, glucuronic acid, glucose and rhamnose are bonded in this order, (B) a (meth)acrylic polymer and (Cl) an ester compound comprising a carboxylic acid residue comprising a residue of a C16 to C22 fatty acid and an alcohol residue having polyglycerin residue or glycerin residue.

Description

OIL-IN-WATER EMULSION

Technical Field

[0001] The present invention relates to an oil-in-water emulsion.

Background Art

[0002] Oil-in-water emulsions must impart a light and fluffy texture when applied onto keratinic materials such as skin, while also leaving virtually no residue on the skin and maintaining high moisture retention for long periods.

[0003] Oil-in-water emulsions are known from Japanese Unexamined Patent Publication No. 2009-234950 and Japanese Unexamined Patent Publication No. 2007-8901, which disclose cosmetics comprising a specific polysaccharide.

Technical Problem

[0004] Oil-in-water emulsions contain various components, and usually include electrolytes as active components. Active research by the present inventors has shown that electrolyte components disrupt the normal dispersed state of an oil-in-water emulsion and lower its stability. Moreover, if the stability of an oil-in-water emulsion to electrolytes is enhanced simply by increasing concentration of thickeners, the oil-in-water emulsion is hard to collapse by electrolytes present on the surface of skin and the like, and it causes heavy and dense texture when the oil-in- water emulsion is applied onto keratinic materials such as skin.

Solution to Problem

[0005] So, the present disclosure has been devised in light of this situation and its object is to provide an oil-in-water emulsion that is more stable to electrolyte.

Summary of the invention

[0006] The oil-in-water emulsion of the invention comprises (A) a polysaccharide with a main chain having a structural unit in which glucose-glucuronic acid-glucose-rhamnose are bonded in that order, (B) a (meth)acrylic-based copolymer, and (Cl) an ester compound having a carboxylic acid residue that includes a C 16 to C22 fatty acid residue, and an alcohol residue that includes a polyglycerin residue or glycerin residue.

[0007] In a particular embodiment, Component (A) comprises rhamnose as a constituent monosaccharide of a side chain. [0008] Component (A) is preferably Diutan gum.

[0009] In a particular embodiment, the content of component (A) is 0.01 to 5 mass%, preferably 0.05 to 2 mass%, more preferably 0.05 to 0.5 mass% based on the total mass of the oil-in-water emulsion.

[0010] The (meth)acrylic-based copolymer is preferably crosslinked.

[0011] The (meth)acrylic-based copolymer is preferably chosen from carbomer, C10-C30 alkyl acrylate copolymers and mixture thereof.

[0012] In a particular embodiment, the content of component (B) is 0.01 to 5 mass%, preferably 0.05 to 2 mass%, more preferably 0.1 to 1 mass% based on the total mass of the oil-in-water emulsion.

[0013] In a particular embodiment, Component (Cl) is chosen from esters of polyglycerol and C16-C22 fatty acid, ester of glycerol and C16-C22 fatty acids, esters obtained by reaction of polyacids with esters of C16-C22 fatty acids and glycerol.

[0014] In a particular and preferred embodiment, Component (Cl) comprises at least glyceryl stearate citrate.

[0015] In a particular embodiment, the oil-in-water emulsion further includes (C2) a C 16 to C22 fatty alcohol.

[0016] In a particular embodiment, the sum of the contents of components (Cl) and (C2) is 0.05 to 15 mass%, preferably 0.1 to 10 mass%, more preferably 0.5 to 5 mass% based on the total mass of the oil-in-water emulsion.

[0017] In a particular embodiment, the carboxylic acid residue has a residue of a compound with a Cl to C 8 carboxyl group.

[0018] Another aspect of the invention is a cosmetic process for caring for and/or dressing keratinic materials, comprising the application onto keratinic materials, in particular onto skin, of the oil-in-water emulsion of the present invention.

[0019] The oil-in-water emulsion of the present invention preferably provides to the keratinic materials on which it is applied, a non-transfer effect, a long-lasting effect, a high coverage effect and a comfort finish.

Advantageous Effects of Invention

[0020] According to the invention it is possible to provide an oil-in-water emulsion that is more stable to electrolyte. Detailed description of the invention

[0021] The oil-in-water emulsion of the invention comprises (A) a polysaccharide with a main chain having a structural unit in which glucose-glucuronic acid-glucose-rhamnose are bonded in that order, (B) a (meth)acrylic-based copolymer, and (Cl) an ester compound having a carboxylic acid residue that includes a C 16 to C22 fatty acid residue, and an alcohol residue that includes a polyglycerin residue or glycerin residue.

Component (A

[0022] Component (A) is a polysaccharide, having a unit with glucose-glucuronic acid-glucose- rhamnose one-dimensionally bonded in that order as the structural unit of the main chain. The structural unit is preferably one represented by the following formula (I).

wherein

R is a hydrogen atom or a side chain including a sugar as a structural unit, and the

notation indicates the binding site with the structural unit.

[0023] In a particular embodiment, the side chain includes a unit derived from 1 to 3 monosaccharides (that is, monosaccharides composing the side chain), and preferably includes a unit derived from 1 or 2 monosaccharides. The side chain preferably contains a unit derived from mannose or rhamnose, and more preferably it includes a unit derived from rhamnose, being preferably a structural unit represented by the following formula (II).

[0024] Throughout the present specification, a “unit derived from a monosaccharide” is a unit wherein a monosaccharide is glycoside-bonded to the main chain, or a unit wherein a monosaccharide is further glycoside-bonded to a unit of a monosaccharide glycoside-bonded to the main chain. Component (A) is a structural unit represented by formula (I), and it may include two or more structural units with different side chains.

[0025] In a particular embodiment, Component (A) is a polysaccharide produced by a Sphingomonas bacterium. In a particular embodiment Component (A) is a Sphingomonas fermentation extract. In a preferred embodiment, component (A) includes either or both diutan gum and welan gum, more preferably diutan gum.

[0026] The oil-in-water emulsion may also include one or more different types of component (A). From the viewpoint of further increasing the stability of the oil-in-water emulsion, the content of component (A) is 0.01 mass% or greater, 0.02 mass% or greater, 0.03 mass% or greater, 0.05 mass% or greater or 0.07 mass% or greater, and 5.0 mass% or lower, 2.0 mass% or lower, 1.0 mass% or lower, 0.8 mass% or lower, 0.6 mass% or lower, 0.5 mass% or lower, 0.4 mass% or lower, 0.3 mass% or lower or 0.25 mass% or lower, for example, with respect to total amount of the oil-in-water emulsion. In a particular embodiment, the total content of component (A) with respect to the total amount of the aqueous emulsion is in the range of 0.01 to 1.0 mass% or especially 0.05 to 0.5 mass%.

Component (B)

[0027] Component (B) is a (meth)acrylic-based copolymer. In a particular embodiment, a (meth)acrylic-based copolymer according to the invention is a polymer obtained by polymerizing one or more monomers selected from the group consisting of (meth)acrylic acid and (meth)acrylic acid esters. There are no particular restrictions on the (meth)acrylic acid ester, which may be an alkyl (meth)acrylic acid ester, or the same wherein the alkyl group of the (meth)acrylic acid ester has been substituted with a substituent such as a hydroxyl group, and it is preferably an alkyl (meth)acrylic acid ester. Alkyl (meth)acrylic acid esters include alkyl (meth)acrylic acid esters with CIO to C30 alkyl groups and alkyl (meth)acrylic acid esters with Cl to C9 alkyl groups, and are preferably alkyl (meth)acrylic acid esters with CIO to C30 alkyl groups. In a particular embodiment, Component (B) is a copolymer of at least one monomer selected from the group consisting of (meth)acrylic acid and alkyl (meth)acrylic acid esters with Cl to C9 alkyl groups, and at least one monomer selected from the group consisting of alkyl (meth)acrylic acid esters with CIO to C30 alkyl groups.

[0028] In a particular embodiment, Component (B) comprises a structural unit derived from (meth)acrylic acid. A structural unit derived from (meth)acrylic acid is a structural unit obtained by radical addition polymerization of (meth)acrylic acid. A structural unit obtained by radical addition polymerization may be any one with the same chemical structure as a structural unit obtained by radical addition polymerization, and may optionally be a structural unit obtained by a method other than radical addition polymerization.

[0029] In a particular and preferred embodiment, Component (B) is crosslinked. The crosslinking agent may be a compound having a plurality of ethylenic unsaturated groups in the molecule, such as a compound with a plurality of allyl ether groups in the molecule. Specifically, the crosslinking agent may be pentaerythrityl allyl ether, sucrose allyl ether, propylene allyl ether or sucrose allyl ether. Component (B) may be crosslinked with one or more crosslinking agents. [0030] When component (B) is a carboxy group, at least a portion of the carboxy groups may be neutralized. As used herein, "carboxy group" includes both the group COOH and the neutralized COOH group. When the carboxy group is neutralized, the counter cation of the carboxylic acid anion is not particularly restricted, and examples include alkali metal ions such as sodium ion and potassium ion, and ammonium ion or organic ammonium ions.

[0031] In a particular embodiment, Component (B) is chosen from carbomer, C10-C30 alkyl acrylate copolymers and mixture thereof. Component (B) may be a commercial product, examples of commercial products including Carbopol™ Ultrez 30 Polymer, Carbopol™ Ultrez 10, Carbopol™ ETD 2020 and Carbopol™ Ultrez 20 Polymer, by Lubrizol Corp.

[0032] The oil-in-water emulsion may also include one or more different types of component (B). From the viewpoint of further increasing the stability of the oil-in-water emulsion, the total content of component (B) is 0.01 mass% or greater, 0.05 mass% or greater, 0.1 mass% or greater, 0.15 mass% or greater, 0.2 mass% or greater or 0.25 mass% or greater, and 5.0 mass% or lower, 2.0 mass% or lower, 1.0 mass% or lower, 0.8 mass% or lower, 0.7 mass% or lower, 0.6 mass% or lower or 0.5 mass% or lower, for example, with respect to the total amount of the oil-in-water emulsion. In a particular embodiment, the total content of component (B) with respect to the total amount of the aqueous emulsion is the range of 0.01 to 5 mass%, 0.05 to 2 mass%, 0.1 to 1 mass% or especially 0.1 to 0.5 mass%.

Component (Cl)

[0033] Component (C 1) is an ester compound, and may be considered to be a compound having an ester bond obtained by formally reacting a carboxylic acid with an alcohol. The portions other than the ester bond derived from a carboxylic acid and alcohol that can formally produce component (Cl) are a carboxylic acid residue and alcohol residue, respectively. The number of carbon atoms in the fatty acid residue of component (Cl) is preferably 16 to 20 and more preferably 18. Examples of fatty acid residues include residues of fatty acids such as palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, a-linolenic acid, y-linolenic acid, isostearic acid, arachidic acid, arachidonic acid and behenic acid. The fatty acid may be saturated or unsaturated, but it is preferably saturated. In a particular embodiment, Component (Cl) includes one or more fatty acid residues. Component (Cl) can also function as an emulsifying agent in the oil-in-water emulsion. [0034] In a particular embodiment, Component (Cl) is chosen from esters of polyglycerol and C16-C22 fatty acid, ester of glycerol and C16-C22 fatty acids, esters obtained by reaction of polyacids with esters of C16-C22 fatty acids and glycerol. In a particular embodiment, the polyacid is a polycarboxylic acid, in particular is a polycarboxylic acid having a hydroxy group, for example, citric acid.

[0035] In a particular embodiment, the polymerization degree of the glycerin in component (Cl) is 2 to 10, and is preferably 2 to 4 and more preferably 2. According to a specific embodiment, component (Cl) is selected from the group consisting of polyglyceryl-2 stearate, polyglyceryl-2 isostearate, polyglyceryl-2 oleate, and mixtures of the same.

[0036] In a particular embodiment, Component (Cl) includes a carboxylic acid residue other than a fatty acid residue. Examples of such carboxylic acid residues include residues of Cl to C8 carboxylic acids (hereunder referred to as short-chain carboxylic acids). The number of carbon atoms of the short-chain carboxylic acid may be 2 to 7, or 3 to 6. Short-chain carboxylic acids include aliphatic monocarboxylic acids such as acetic acid, propionic acid, valeric acid, caproic acid and caprylic acid, aliphatic dicarboxylic acids such as succinic acid; and hydroxy acids such as lactic acid and citric acid. Hydroxy acid residues may be considered to be carboxylic acid residues where the carboxy group of the hydroxy acid forms an ester bond. In a particular and preferred embodiment, Component (Cl) comprises at least glyceryl stearate citrate.

Component (C2) (optional)

[0037] In a particular embodiment, the oil-in-water emulsion comprises (C2) a C 16 to C22 fatty alcohol. The number of carbon atoms in the fatty alcohol is preferably 16 to 20 and more preferably 18. In a particular embodiment, Component (C2) is myristyl alcohol, cetanol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, arachidyl alcohol or behenyl alcohol, for example. A fatty alcohol may be saturated or unsaturated, but is preferably saturated. According to a specific embodiment, component (C2) is stearyl alcohol, oleyl alcohol, cetanol or behenyl alcohol, or a mixture thereof. [0038] The oil-in-water emulsion may comprise both component (Cl) and component (C2). In this case, component (Cl) does not need to include a short-chain carboxylic acid residue.

[0039] In a particular embodiment, the sum of the contents of component (Cl) and component (C2) is 0.05 mass% or greater, 0.10 mass% or greater, 0.50 mass% or greater, 1.0 mass% or greater, or 1.2 mass% or greater, and 15 mass% or lower, 10 mass% or lower, 8.0 mass% or lower, or lower or 5.0 mass% or lower, with respect to the total amount of the oil-in-water emulsion. In a particular embodiment, the sum of the contents of component (Cl) and (C2) is 0.05 to 15 mass%, preferably 0.1 to 10 mass%, more preferably 0.5 to 5 mass% based on the total amount of the oil- in-water emulsion.

[0040] In a particular embodiment, the content of component (Cl) that includes a short-chain carboxylic acid residue is 0.1 mass% or greater, 0.2 mass% or greater, 0.3 mass% or greater or 0.5 mass% or greater, and 15 mass% or lower, 10 mass% or lower, 8.0 mass% or lower or 5.0 mass% or lower, with respect to the total amount of the oil-in-water emulsion.

[0041] In a particular embodiment, the content of component (C2) is 0.03 mass% or greater, 0.05 mass% or greater, 0.08 mass% or greater or 0.10 mass% or greater, and 15 mass% or lower, 10 mass% or lower, 8.0 mass% or lower or 5.0 mass% or lower, with respect to the total amount of the oil-in-water emulsion.

[0042] In a particular embodiment, the content of component (C2) is 5 mass% or greater, 10 mass% or greater, 15 mass% or greater or 20 mass% or greater, and 45 mass% or lower, 40 mass% or lower, 35 mass% or lower or 30 mass% or lower, with respect to the total amount of component (Cl) without a short-chain carboxylic acid residue, and component (C2).

[0043] In a particular embodiment, the content of ester compounds having a C16 to C22 fatty acid residue and a polyglycerin residue is 0.05 mass% or greater, 0.10 mass% or greater, 0.15 mass% or greater or 0.20 mass% or greater, and 15 mass% or lower, 10 mass% or lower, 8.0 mass% or lower or 5.0 mass% or lower, with respect to the total amount of the oil-in-water emulsion.

[0044] In a particular embodiment, the content of component (Cl) is 0.05 mass% or greater, 0.1 mass% or greater, 0.2 mass% or greater, 0.3 mass% or greater or 0.5 mass% or greater, and 15 mass% or lower, 10 mass% or lower, 8.0 mass%, 5.0 mass% or lower, 4.0 mass% or lower, 3.0 mass% or lower, 2.5 mass% or 2.0 mass% or lower, with respect to the total amount of the oil- in-water emulsion. In a particular embodiment, the total content of component (Cl) with respect to the total amount of the aqueous emulsion is in the range of 0.05 to 15 mass%, 0.1 to 10 mass% or 0.5 to 5 mass%.

Additional thickener (optional)

[0045] According to a specific embodiment, the oil-in-water emulsion further comprises a thickener. The thickener, however, is one that is not included among component (A) or component (B). Examples of thickeners include polysaccharide thickeners such as xanthan gum and agarose. [0046] In a particular embodiment, the content of the additional thickener is 0.01 mass% or greater, 0.1 mass% or greater, 0.15 mass% or greater, 0.2 mass% or greater, 0.3 mass% or greater, 0.4 mass% or greater or 0.5 mass% or greater, and 1.0 mass% or lower, 0.8 mass% or lower, 0.5 mass% or lower, 0.3 mass% or lower or 0.2 mass% or lower, for example, with respect to the total amount of the oil-in-water emulsion. In a particular embodiment, the additional thickener content is most preferably 0.01 to 1 mass% with respect to the total amount of the oil-in-water emulsion.

Oil agent

[0047] According to a specific embodiment, the oil-in-water emulsion includes an oil agent other than components (Cl) and (C2). The oil agent may be a liquid oil or a paste oil, for example. A liquid oil may be either a non-polar liquid oil or a polar liquid oil. Examples of liquid oils include alkyl palm (caprylates/caprates), squalane, sunflower oil, dimethicone, meadowfoam oil, almond oil, polyglyceryl-2 triisostearate, glyceryl tri(capry late/ caprate), isotridecyl isononanoate, isononyl isononanoate, ethyl hexyl palmitate, pentaerythrityl tetraethyl hexanoate, pentaerythrityl tetraisostearate, cetyl ethylhexanoate, hydrogenated polydecene and hydrogenated polyisobutene, as well as their mixtures.

[0048] In a particular embodiment, the content of the oil agent with respect to the total amount of the oil-in-water emulsion is 0.3 mass% or greater, 0.5 mass% or greater, 0.5 mass% or greater, 1 mass% or greater, 5 mass% or greater, 7 mass% or greater, 8 mass% or greater, 10 mass% or greater, 12 mass% or greater, 14 mass% or greater or 16 mass% or greater, and 40 mass% or lower, 30 mass% or lower, 20 mass% or lower, 18 mass% or lower, 17 mass% or lower, 15 mass% or lower, 13 mass% or lower, or 10 mass% or lower, for example. In a particular embodiment, the oil agent content is in the range of 0.5 mass% to 40 mass% and especially 1 mass% to 30 mass%, with respect to the total amount of the oil-in-water emulsion.

[0049] In a particular embodiment, the liquid oil content with respect to the total amount of the oil-in-water emulsion is 0.1 mass% or greater, 0.3 mass% or greater, 0.5 mass% or greater, 1 mass% or greater, 3 mass% or greater, 5 mass% or greater, 7 mass% or greater, 8 mass% or greater, 10 mass% or greater, 12 mass% or greater or 14 mass% or greater, and 40 mass% or lower, 30 mass% or lower, 20 mass% or lower, 18 mass% or lower, 17 mass% or lower, 15 mass% or lower, 13 mass% or lower, 10 mass% or lower or 8 mass% or lower, for example. In a particular embodiment, the liquid oil content is in the range of 0.3 mass% to 40 mass% and especially 0.5 mass% to 30 mass%, with respect to the total amount of the oil-in-water emulsion.

[0050] According to a specific embodiment, the oil-in-water emulsion may also contain additives commonly used in cosmetics, such as humectants, pH adjustors, perfumes, preservatives, active components, antioxidants, UV blockers, skin whiteners, pigments, coloring agents, and skin conditioning agents. According to a specific embodiment, the oil-in-water emulsion comprises an active component.

[0051] Examples of humectants include C3 to C5 polyhydric alcohols. Examples of polyhydric alcohols include those with 2 or 3 alcoholic hydroxyl groups. Examples of polyhydric alcohols include glycerin, 1,3 -butylene glycol, pentylene glycol, propanediol, and mixtures thereof. In a particular embodiment, the oil-in-water emulsion comprises polyhydric alcohol(s) selected in the group consisting of glycerin, 1,3-butylene glycol, pentylene glycol, propanediol, and mixtures thereof.

[0052] In a particular embodiment, the total content of C3 to C5 polyhydric alcohol(s) with respect to the total amount of the oil-in-water emulsion is 2 mass% or greater, 5 mass% or greater, 8 mass% or greater, 10 mass% or greater, 12 mass% or greater, 15 mass% or greater, 18 mass% or greater or 20 mass% or greater, and 30 mass% or lower, 28 mass% or lower, 25 mass% or lower, 23 mass% or lower, 20 mass% or lower, 18 mass% or lower or 15 mass% or lower, for example. In a particular embodiment, the total content of C3 to C5 polyhydric alcohol(s) is in the range of 2 mass% to 30 mass% and especially 5 mass% to 30 mass%, with respect to the total amount of the oil-in-water emulsion.

[0053] In a particular embodiment, the pH of the oil-in-water emulsion is 3 to 9 or 4 to 8, for example.

[0054] According to a specific embodiment, the oil-in-water emulsion has a viscosity of 5,000 to 100,000 mPa-s or 8,000 to 50,000 mPa-s, for example, as measured at 25°C. In a particular embodiment, the viscosity is measured based on the shear viscosity, using a rotational viscometer (for example, Rheolab QC by Anton Paar, spindle: ST-24-2D/2 V/2 V-30; rotational speed: 50 rpm).

[0055] The oil-in-water emulsion comprises water. In a particular embodiment, the total content of water with respect to the total amount of the oil-in-water emulsion is 40 mass% or greater, 43 mass% or greater, 45 mass% or greater, 47 mass% or greater, 49 mass% or greater, 51 mass% or greater, 53 mass% or greater, 55 mass% or greater, 58 mass% or greater, 60 mass% or greater or 61 mass% or greater, and 70 mass% or lower, 65 mass% or lower, 63 mass% or lower, 61 mass% or lower, 59 mass% or lower or 57 mass% or lower, for example. In a particular embodiment, the total water content is in the range of 40 mass% to 90 mass% and 49 mass% to 80 mass%, with respect to the total amount of the oil-in-water emulsion.

[0056] According to a specific embodiment, the oil-in-water emulsion is produced, for example, by stirring and mixing component (A), component (B), component (Cl), and water with the additional thickener, oil agent or emulsifying agent, while heating at 80 to 85°C, and then cooling the mixture to room temperature and mixing in the other components.

[0057] According to another specific embodiment, the oil-in-water emulsion is in the form of a cream or fluid, for example. In a particular embodiment, the oil-in-water emulsion is a cosmetic, and is preferably a skin care cosmetic.

[0058] In a particular embodiment, the oil-in-water emulsion of the invention also comprises an active substance. In a particular embodiment, the active substance that is an electrolyte includes an acid having an acidity constant pKa of 5 or lower or the salt there of, in particular an acid having an acidity constant pKa of 4.5 or lower or the salt there of. If the active substance having a multiplicity of acidic groups, an acidity constant pKa may be pKal. More specifically, active electrolyte components include ascorbic acid, ascorbic acid derivatives and salts thereof. Ascorbic acid derivatives include ascorbic acid esters such as ascorbic acid 2-glucoside. In a particular embodiment, ascorbic acid is L-ascorbic acid. In a particular embodiment, ascorbic acid derivatives are L-ascorbic acid derivatives.

[0059] Another aspect of the invention is a cosmetic process for caring for and/or making-up keratinic materials (for example, skin, lips, nail and the like), comprising the application onto keratinic materials, in particular onto skin, of the oil-in-water emulsion above described. In a particular embodiment, the oil-in-water emulsion provides to the keratinic materials on which it is applied, non-transfer effect, long lasting effect, high coverage effect and comfort finish.

The present invention will now be further explained using the non-limitative following examples and comparative examples.

Examples

[0060] Oil-in-water emulsions were prepared having the mixing ratios listed in Tables 1 and 2. The numerical values in Tables 1 and 2 are mass% values. The totals are all 100 mass%. The active component and a pH adjustor were dissolved at room temperature. The active component included ascorbic acid 2-glucoside. A purified water, a humectant and a preservative were then loaded into the tank and mixed in at 80 to 85°C. A thickener was added to and mixed in the tank to have the mixture swell. The oil and component (Cl) were added to the tank and mixed to have the mixture emulsified. The mixture was then cooled to 30°C, mixing in the other materials at the point where the temperature fell below 40°C, to obtain an oil-in-water emulsion.

[0061] The following are the details for the materials listed in the tables.

Sphingomonas Ferment Extract: KELCO-CARE DIUTAN GUM, Lubrizol Corp.

Carbomer*¹: CARBOPOL ULTREZ 30 POLYMER, Lubrizol Corp.

Carbomer*²: CARBOPOL ULTREZ 10, Lubrizol Corp.

(Acrylates/C 10-30) alkyl acrylate crosspolymer: CARBOPOL ETD 2020, Lubrizol Corp. Hydroxypropyl Methylcellulose Stearoxy Ether: SANGELOSE 90L, Daidokasei Co., Ltd. Agar.: INA KANTEN CS-310TR, Ina Eood Industry Co., Ltd.

Algin: GELCARIN EE46, DuPont.

Sclerotium Gum: AMIGEL GRANULE, Alban Muller International.

Tapioca Starch: TAPIOCA NATURAL 9096, Agrana.

Dehydroxanthan Gum (and) Water: AMAZE XT, Nouryon.

Polyglyceryl-2 stearate, glyceryl stearate, and stearyl alcohol: POLYAQUOL 2W, Innovacos Corp. Glyceryl citrate stearate: DERMOPEEL GSC, Evonik, Japan

The stability and viscosity were evaluated for each obtained oil-in-water emulsion (illustrative examples and comparative examples).

[0062] [Stability evaluation]

The stability of each obtained oil-in-water emulsion was evaluated by the following method. A 30 g portion of the oil-in-water emulsion was placed in a transparent container (50 mL). The cover of the glass bottle was then sealed. The glass bottle was stored at a constant temperature of 50°C or 40°C. After standing for 1 month at 50°C or 6 months at 40°C, the emulsion was observed. The results are shown in Tables 3 and 4. The term “stable” in the tables indicates that no phase separation was observed, "water exudation" indicates that the oil phase and aqueous phase separated and exudation of water was observed, and "not smooth" indicates that non-smooth irregularities due to aggregate formation in the composition was observed.

[0063] [Viscosity measurement]

The viscosities of the obtained oil-in-water emulsions were measured. Each viscosity was measured at 25°C based on the shear viscosity, using a rotational viscometer (for example, Rheolab QC by Anton Paar, spindle: ST-24-2D/2 V/2 V-30; rotational speed: 50 rpm). The results are shown in Tables 3 and 4. The emulsions evaluated as ‘stable’ and smooth for all conditions (1 month at 50°C and also 6 months at 40°C) are acceptable in the context of the invention.

[0064] As shown in Tables 3 and 4, each of the oil-in-water emulsions of the Examples were stable at 1 month at 50°C and also 6 months at 40°C, without visible phase separation or component aggregation after stability testing. Each of the oil-in-water emulsions of the Comparative Examples were not stable, exhibiting phase separation or component aggregation after stability testing.

[0065] So these results demonstrate that the combination of (A) a polysaccharide having a main chain containing a structural unit in which glucose, glucuronic acid, glucose and rhamnose are bonded in this order, (B) a (meth)acrylic polymer and (Cl) an ester compound comprising a carboxylic acid residue comprising a residue of a C16 to C22 fatty acid and an alcohol residue having polyglycerin residue or glycerin residue, in oil-in-water emulsion, permits to obtain a stable emulsion, even in the presence of active components (electrolytes).

Claims

1. An oil-in-water emulsion comprising;

(A) a polysaccharide having a main chain containing a structural unit in which glucose, glucuronic acid, glucose and rhamnose are bonded in this order,

(B) a (meth)acrylic polymer and

(Cl) an ester compound comprising a carboxylic acid residue comprising a residue of a C16 to C22 fatty acid and an alcohol residue having polyglycerin residue or glycerin residue.

2. The oil-in-water emulsion according to claim 1, wherein component (A) comprises rhamnose as a constituent monosaccharide of a side chain.

3. The oil-in-water emulsion according to claim 1 or 2, wherein component (A) is Diutan Gum.

4. The oil-in-water emulsion according to any one of claims 1 to 3, wherein the content of component (A) is 0.01 to 5 mass%, preferably 0.05 to 2 mass%, more preferably 0.05 to 0.5 mass% based on the total amount of the oil-in-water emulsion.

5. The oil-in-water emulsion according to any one of claims 1 to 4, wherein the (meth)acrylic polymer is crosslinked.

6. The oil-in-water emulsion according to any one of claims 1 to 5, wherein the (meth)acrylic polymer is chosen from carbomer, C10-C30 alkyl acrylate copolymers and mixture thereof.

7. The oil-in-water emulsion according to any one of claims 1 to 6, wherein the content of component (B) is 0.01 to 5 mass%, preferably 0.05 to 2 mass%, more preferably 0.1 to 1 mass% based on the total amount of the oil-in-water emulsion.

8. The oil-in-water emulsion according to any one of claims 1 to 7, wherein component (Cl) is chosen from esters of polyglycerol and C16-C22 fatty acid, ester of glycerol and C16-C22 fatty acids, esters obtained by reaction of polyacids with esters of C16-C22 fatty acids and glycerol.

9. The oil-in-water emulsion according to any one of claims 1 to 8, wherein component (Cl) comprises at least glyceryl stearate citrate.

10. The oil-in-water emulsion according to any one of claims 1 to 9, further comprising (C2) a C16 to C22 fatty alcohol.

11. The oil-in-water emulsion according to any one of claims 1 to 10, wherein the sum of the contents of component (Cl) and (C2) is 0.05 to 15 mass%, preferably 0.1 to 10 mass%, more preferably 0.5 to 5 mass% based on the total amount of the oil-in-water emulsion.

12. A cosmetic process for caring for and/or making-up keratinic materials, comprising the application onto keratinic materials, in particular onto skin, of the oil-in-water emulsion according to any one of claims 1 to 11.

13. A cosmetic process according to claim 12, wherein the oil-in-water emulsion provides to the keratinic materials on which it is applied, non-transfer effect, long lasting effect, high coverage effect and comfort finish.