WO2021149809A1 - Oil-in-water-type emulsified cosmetic material - Google Patents

Abstract

The objective of the present invention is to provide an oil-in-water-type emulsified cosmetic material that has an appropriate richness when applied to the skin, and then collapses to give a refreshing feel like a moist feel, and that also has excellent emulsification stability. The present invention relates to an oil-in-water-type emulsified cosmetic material containing (A) an associative thickener, (B) a water-absorbing polymer, and (C) polar oil, the oil-in-water-type emulsified cosmetic material being characterized in that an added amount of (C) the polar oil is 3-30 mass% with respect to the total amount of the cosmetic material, and the product (X×Y) of a water absorption rate (X) of (B) the water-absorbing polymer and an added amount (Y mass%) thereof falls within the range of 20-75.

Description

Underwater oil type emulsified cosmetic

The present invention relates to an oil-in-water emulsified cosmetic that is stable, has no stickiness, and has a fresh feel while blending a predetermined amount of polar oil. More specifically, an oil-in-water emulsified cosmetic that has excellent emulsion stability even when a relatively large amount of polar oil is blended, is not sticky, and can give a fresh feeling of use such that it collapses after application and overflows with water. Regarding.

The oil-in-water emulsification base is preferred as a cosmetic base that gives a fresh feeling of use because the outer phase (continuous phase), that is, the phase that first comes into contact with the skin is the aqueous phase. Various attempts have been made to further improve and make attractive cosmetics while making the best use of such characteristics of oil-in-water emulsification bases.

For example, the cosmetic base described in Patent Document 1 has a sherbet-like appearance that gives a visually refreshing sensation, and when applied to the skin, it instantly softens and bursts, causing the water to overflow. It can give a feeling of collapse). The cosmetic base of Patent Document 1 contains 0.15 to 0.6% by mass of Na-acrylic acid graft starch, which is a super absorbent polymer capable of absorbing 600 to 700 times its own weight, and is co-blended. By setting the total blending amount with the associative thickener having an oxyalkylene chain in the range of 0.5 to 1.5% by mass, a unique appearance and usability are exhibited. In order to take advantage of such a unique appearance and usability, it is said that it is preferable to use an "aqueous base".

On the other hand, it is known that by blending an oil component with an oil-in-water emulsification base that gives a fresh feel, it is possible to give a rich application feeling and a glossy skin feeling. However, when the amount of oil, especially polar oil, is increased, stickiness tends to occur and the emulsification stability tends to decrease.

Patent Document 2 discloses an oil-in-water cosmetic containing a phospholipid and a copolymer of acrylate and dimethyl taurine acrylate, and is rich even if it does not contain a solid oil at room temperature. It is said that it has a feeling of application, spreads well at the time of application, is not sticky, and gives a refreshing feeling of use. However, since it does not contain a water-absorbent polymer or an associative thickener, the feeling of water collapse as in Patent Document 1 cannot be obtained.

Patent Document 3 describes that stickiness was suppressed in a cosmetic composition in the form of an emulsion containing a highly absorbent polymer and an organic UV blocking agent (oil-soluble ultraviolet absorber). The super absorbent polymer used in Patent Document 3 is understood as a water-absorbent polymer defined by the amount of absorbable aqueous fluid (distilled water), but the water-absorbent polymer and the co-blended water-absorbing polymer are mixed. In view of the amount of oil, it is presumed that simply adding the associative thickener to the cosmetic composition of Patent Document 3 does not give the sherbet-like appearance and the feeling of water collapse as in Patent Document 1.

WO2019 / 044880 Japanese Unexamined Patent Publication No. 2002-322026 Japanese Unexamined Patent Publication No. 2011-006413

The present invention is an oil-in-water emulsified cosmetic that, in view of the current state of the art, can give a fresh feel as if it collapses and then overflows water, while having an appropriate richness when applied to the skin. An object of the present invention is to provide an oil-in-water emulsified cosmetic having excellent emulsion stability.

As a result of diligent research to solve the above problems, the present inventor has added a predetermined amount of polar oil to an oil-in-water emulsified cosmetic containing an associative thickener and a water-absorbing polymer, and the water-absorbing material. By adjusting the water absorption of the sex polymer within a predetermined range, not only can the polar oil be stably retained, but it is not sticky and has an appropriate richness at the time of application, but then collapses and the water overflows. We have found that it can give a fresh feeling, and have completed the present invention.

That is, the present invention
(A) Associative thickener,
An oil-in-water emulsified cosmetic containing (B) a water-absorbent polymer and (C) a polar oil.
The blending amount of the polar oil (C) is 3 to 30% by mass with respect to the total amount of cosmetics.
An oil-in-water emulsified cosmetic according to the product (X × Y) of the water absorption rate (X) of the water-absorbent polymer (B) and the blending amount (Y mass%) thereof is in the range of 20 to 75. I will provide a.

Since the oil-in-water emulsified cosmetic of the present invention contains a water-absorbing polymer and an associative thickener, it is not sticky and collapses like the cosmetic base of Patent Document 1 so that water overflows. It has a fresh feel. However, since the water absorption amount of the water-absorbent polymer is limited and a predetermined amount of polar oil is blended, there is an appropriate richness when applying, and the cosmetic can be applied by pressing with a finger or hand after application. Gives the feeling that water spreads on the skin with the feeling that water pops out from inside. This feeling of use is referred to as "collapse feeling" in the present specification. The "collapse feeling" obtained by the cosmetic of the present invention means a feeling of freshness after a short time after being applied to the skin, and the "sherbet instantly when applied" obtained by the cosmetic of Patent Document 1. It is different from the feeling that the cosmetics in the shape collapse and the water overflows (feeling of water collapse).
In addition, the oil-in-water emulsified cosmetic of the present invention can stably retain an oil-soluble agent such as an ultraviolet absorber as a polar oil, so that it has a unique fresh feeling of use (collapse feeling) and a high ultraviolet protection effect (high SPF (Sun)). It is possible to use a skin care cosmetic having a protection factor)), for example, a sunscreen.

The oil-in-water emulsified cosmetic of the present invention (hereinafter, also simply referred to as “cosmetic”) contains (A) an associative thickener, (B) a water-absorbent polymer, and (C) polar oil as essential components. ..

(A) Associative thickener The "associative thickener" is a copolymer having a hydrophilic part made of a water-soluble monomer and a hydrophobic part made of a hydrophobic monomer, and is hydrophobic to each other in an aqueous solvent. It is a thickener having an action of thickening the system by acting as if it behaves as a physically crosslinked macromolecule by associating by action (see, for example, paragraph 0014 of JP-A-2000-239120).

The associative thickener (component A) in the present invention is selected from the group consisting of (A-1) hydrophobically modified polyether urethane, (A-2) hydrophobically modified alkyl cellulose, and (A-3) polyacrylate crosspolymer. It is preferable that the amount is at least one. In the present invention, one of the associative thickeners belonging to any of (A-1) hydrophobically modified polyether urethane, (A-2) hydrophobically modified alkyl cellulose, and (A-3) polyacrylate crosspolymer. Species or two or more species may be used, and a plurality of or two or more species of (A-1), (A-2) and (A-3) may be blended in combination.

(A-1) Hydrophobic Modified Polyether Urethane As the hydrophobic modified polyether urethane (A-1 component) used in the present invention, the following general formula (1):

(In the formula, R ¹ is an aliphatic hydrocarbon group having 24 to 36 carbon atoms, and m represents a number of 0 to 1000), the monohydroxy compound (I) represented by the following general formula (2). ):

Polyethylene glycol (II) represented by (in the formula, n represents a number from 2 to 1000), the following general formula (3):

(In the formula, R ² represents an aliphatic hydrocarbon group having 5 to 12 carbon atoms), and the monoglyceryl ether compound (III) represented by the following general formula (4):

A urethane-type polymer obtained by reacting an isocyanate compound (IV) represented by (R ³ represents a hydrocarbon group having 4 to 13 carbon atoms and q represents a number of 2 or 3) in the formula. It can be exemplified.

This urethane type polymer is obtained by reacting the above compounds (I) to (IV). Specifically, the hydroxyl group contained in each of the compounds (I), (II) and (III) reacts with the isocyanate group contained in (IV). Since there are three types of compounds having hydroxyl groups, two of which are divalent, the resulting polymer has a complex structure and cannot be represented by an appropriate general formula.

The method for producing this urethane-type polymer may be a reaction of each compound in a batch or a reaction in a divided manner, and is not particularly specified as long as the four compounds react. However, even if any of the compounds (I) to (III) is put into the reaction system after the isocyanate compound (IV) has completely reacted, the reaction does not occur. Therefore, the compounds (I) to (III) are mixed in advance. , It is preferable to add the isocyanate compound (IV) to the reaction. Specifically, the compounds (I) to (III) are placed in a reaction system, melt-mixed at 40 to 100 ° C., preferably 60 to 80 ° C., and the isocyanate compound (IV) is reacted while maintaining the same temperature. Add to the system and react. Then, it may be aged at the same temperature for 30 minutes to 3 hours until the reaction is completed.

In the above reaction, the compounding ratio of each component is not particularly specified, but since the function as a viscosity modifier is improved and the reaction is easy to control, a monohydroxy compound (monohydroxy compound) is used based on 10 mol of polyethylene glycol (II). It is preferable that the amount of I) is 10 to 30 mol, the amount of monoglyceryl ether compound (III) is 5 to 20 mol, and the amount of isocyanate compound (IV) is 20 to 50 mol. More preferably, compound (I) is 15 to 25 mol, monoglyceryl ether compound (III) is 8 to 15 mol, and isocyanate compound (IV) is 25 to 40 mol.
Details of this urethane type polymer are described in Japanese Patent No. 6159738.

The hydrophobically modified polyether urethane (A-1 component) in the present invention includes polyethylene glycol ether (tetradecyl octadeces-100) in which the monohydroxy compound (I) is tetradecyl octadecanol, and polyethylene glycol (II). Is PEG-240, the monoglyceryl ether compound (III) is ethylhexyl glycerin, and the isocyanate compound (IV) is hexamethylene diisocyanate (HDI). The copolymer is referred to as "Polyurethane-59" (INCI name: Polyurethane-59) in the cosmetic ingredient labeling name. As the polyurethane-59, a commercially available product may be used, and for example, "ADEKA NOL GT-930" manufactured by ADEKA Corporation is preferably used.

As another example of the hydrophobically modified polyether urethane (A-1 component) in the present invention, the following general formula (I):

Examples thereof include the hydrophobically modified polyether urethane represented by.

In the above formula (I), R ¹ , R ² and R ⁴ independently represent an alkylene group having 2 to 4 carbon atoms or a phenylethylene group, respectively. It is preferably an alkylene group having 2 to 4 carbon atoms.
R ³ represents an alkylene group having 1 to 10 carbon atoms which may have a urethane bond.
R ⁵ represents a linear, branched or secondary alkyl group having 8 to 36 carbon atoms, preferably 12 to 24 carbon atoms.
m is a number of 2 or more, preferably 2. h is a number of 1 or more, preferably 1. k is a number from 1 to 500, preferably a number from 100 to 300. n is a number from 1 to 200, preferably a number from 10 to 100.

Particularly preferred hydrophobically modified polyether urethanes in the present invention are (PEG-240 / decyltetradeceth-20 / HDI) copolymers (copolymers represented by the above formula (I), R ¹ = ethyl group, R ² and Examples of R ⁴ include an ethylene group, R ³ = hexamethylene group, R ⁵ = 2-decyltetradecyl group, h = 1, m = 2, k = 120, and n = 20). The copolymer is commercially available from ADEKA Corporation under the trade name "ADEKANOR GT700" or "ADEKANOL GT730".

(A-2) Hydrophobic Modified Alkyl Cellulose The hydrophobic modified alkyl cellulose (A-2 component) used in the present invention is preferably represented by the general formula (II).

In the above formula (II), R is a binding group R _1- R ₂ , and R ₁ may be the same or different in the molecule, and-[CH ₂ CH (CH ₃ ) O] _r -,-[ CH ₂ CH ₂ O] _r − and − [CH ₂ CH (OH) CH ₂ O] _r − (in the formula, r is an integer of 0 to 4), and R ₂ is , A hydrocarbon group having 12 to 28 carbon atoms (preferably an alkyl group having 1 to 4 carbon atoms), and one or more groups selected from hydrogen atoms, and at least one _{of R 2 in one molecule.} One is a hydrocarbon group having 12 to 28 carbon atoms (preferably an alkyl group having 1 to 4 carbon atoms). A is the group − (CH ₂ ) _t − (t is an integer of 1 to 3), and s is a number from 100 to 10000.

The hydrophobically modified alkyl cellulose of the formula (II) has a structure in which a long-chain alkyl group, which is a hydrophobic group, is introduced into a water-soluble cellulose ether derivative via a polyoxyalkylene chain. The water-soluble cellulose ether derivative on which the molecule is based is, for example, methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose and the like, and long-chain alkyl glycidyl ether (for example, the following formula). It can be obtained by reacting with (II').

In formula (II'), R'is an alkyl group having 10 to 28 carbon atoms, preferably 12 to 22 carbon atoms.

As the water-soluble cellulose ether derivative, hydroxypropylmethylcellulose or hydroxyethylcellulose is preferable, and hydroxypropylmethylcellulose is particularly preferable. Furthermore, the R'of the long-chain alkylglycidyl ether (II') is preferably a stearyl group (-C ₁₈ H ₃₇ ) or a cetyl group (-C ₁₆ H ₃₃ ) (in these cases -CH _2). CH (OH) CH ₂ OR'becomes -CH ₂ CH (OH) CH _{2 OC 18} H ₃₇ or -CH ₂ CH (OH) CH ₂ OC ₁₆ H ₃₃ ).

The most preferable embodiment of the hydrophobically modified alkyl cellulose (A-2 component) is stearoxyhydroxypropylmethyl cellulose (INCI name: Hydroxypropylmethylcellulose Stearoxy Ether) having the hydrophobic group R'in the formula (II') as a stearyl group. It is also possible to use a product marketed by Daido Kasei Kogyo Co., Ltd. under the trade name of "loin". (Product name: Sangelose 90L, 90M, 90H, 60L, 60M, 60H, etc.).

(A-3) Polyacrylate Crosspolymer The polyacrylate crosspolymer (component A-3) used in the present invention is preferably a crosspolymer obtained by cross-linking a polyacrylate-based main chain with a polyoxyalkylene chain. The polyacrylate-based main chain may have various substituents (side chains) as long as it acts as an associative thickener.

As an example of a particularly preferable polyacrylate crosspolymer (A-3 component), polyacrylate crosspolymer-6 (INCI name: Polyacrylate Crosspolymer-6) can be mentioned. Polyacrylate crosspolymer-6 is a copolymer of acryloyldimethyltaurinammonium, dimethylacrylamide, lauryl methacrylate and laures-4 methacrylate crosslinked with trimethylolpropane triacrylate. For example, a product marketed by SEPPIC under the trade name "SEPIMAX ZEN" can be used.

The blending amount of the (A) associative thickener in the present invention is 0.1 to 5.0% by mass, preferably 0.2 to 3.0% by mass, and more preferably 0. 3 to 2.0% by mass. If it is less than 0.1% by mass, a unique feeling of use cannot be realized. On the other hand, if it is blended in excess of 5.0% by mass, stickiness may occur.

(B) Water-absorbent polymer The water-absorbent polymer (component B) in the present invention is a polymer capable of absorbing water having a weight of 2 times or more, preferably 10 times or more, more preferably 20 times or more the weight of the polymer itself. Means. The upper limit of the water absorption amount of the water-absorbent polymer is not particularly limited, but it is preferable to use a water-absorbent polymer having a weight of 700 times or less of its own weight.

In general, the water absorption amount (water absorption rate) of a water-absorbent polymer is often specified by the expression "how many times its own weight can absorb water" as described above, but in the present specification, the water-absorbent polymer "is""Water absorption rate (X)" is defined as follows.
(1) A predetermined amount of the water-absorbent polymer is weighed, and a predetermined amount of water is slowly added while stirring.
(2) Stir at 2000 rpm for 2 minutes or more using a disper to make it uniform.
(3) Stop stirring and let stand for 12 hours or more.
(4) After adjusting to 30 ° C., the viscosity is measured with a B-type viscometer (VISCOMETER TVB-10: TOKI SANGYO).
(5) When the viscosity is less than 4900 mPa · s (30 ° C.), the amount of water added in the step (1) is reduced and the above steps (1) to (4) are repeated, and the viscosity is 5100 mPa · s (30 ° C.). If the amount exceeds, the amount of water added in the step (1) is increased and the above (1) to (4) are repeated, and the viscosity in the step (4) becomes within the range of 5000 ± 100 mPa · s (30 ° C.). The amount of water added at that time is defined as the water absorption rate (X) of the water-absorbent polymer.

Examples of the water-absorbent polymer preferably used in the present invention include (B-1) Acrylate cloth polymer-2-Na and (B-2) Na acrylate-grafted starch. These can be blended alone or in combination of two or more.

(B-1) Acrylate Cross Polymer-2-Na
Acrylate crosspolymer-2-Na (B-1 component) is a sodium salt obtained by cross-linking a copolymer consisting of a monomer of acrylic acid, methacrylic acid or one or more simple esters thereof with ethylene glycol diglycidyl ether. ..

Commercially available products can be used for Acrylate Crosspolymer-2-Na (INCI name: Sodium Acrylates Crosspolymer-2). For example, "ARON NT-Z (manufactured by Toagosei Co., Ltd.)" (water absorption rate = 20 to 22), "AQUAKEEP 10SH-NFC (manufactured by Sumitomo Seika Chemical Co., Ltd.)" (water absorption rate = about 200 to 300), etc. are preferable. used.

(B-2) Na Acrylic Acid Graft Starch The Na Acrylic Acid Graft Starch (B-2 component) in the cosmetics of the present invention is a sodium salt obtained by graft-polymerizing acrylic acid on starch (INCI name: Sodium Polyacrylate Starch:). Water absorption rate = 600-700).

As the sodium acrylate graft starch in the present invention, a commercially available product can be used. For example, MAKIMOUSSE7 (average particle size about 7 μm), MAKIMOUSSE12 (average particle size about 12 μm), MAKIMOUSSE25 (average particle size about 25 μm), and MAKIMOUSSE400 (average particle size about 400 μm) (all manufactured by Daito Kasei Kogyo Co., Ltd.), Sanflesh. Examples thereof include ST-100C, ST100MC and IM-300MC (all manufactured by Sanyo Kasei Kogyo Co., Ltd.).

Further, a super absorbent polymer having starch as a main chain and grafted with an acrylic polymer is also included in the Na-acrylic acid graft starch in the present invention. Commercially available products of such polymers (INCI name: starch / acrylamide / sodium acrylate copolymer) include Water Lock A-240, A-180, B-204, D-223, A-100, C-200 and D. -223 (manufactured by Grain Processing Co., Ltd.) can be mentioned.

The blending amount of the water-absorbent polymer (B component) in the cosmetic of the present invention is 0.06 to 10.0% by mass, preferably 0.1 to 5.0% by mass, more preferably 0, based on the total amount of the cosmetic. .1 to 3.0% by mass. However, the product (X × Y) of the value of the water absorption rate (X) of the blended water-absorbent polymer and the value of the blended amount (Y mass%) of the water-absorbent polymer must be in the range of 20 to 75. Yes, it is more preferably in the range of 20 to 70, and further preferably in the range of 24 to 70. It can be said that "XY" represents the amount of water (water absorption amount) that can be absorbed by the water-absorbent polymer blended in the cosmetic. When the value of the water absorption amount (X × Y) is less than 20, or when it exceeds 75, it is difficult to obtain a unique feeling of use (collapse feeling).

(C) Polar oil The third essential ingredient in the cosmetic of the present invention is polar oil (also referred to as “C component”). The "polar oil" in the present specification is an oil having an IOB value of 0.05 to 0.80. Here, the IOB value means the ratio of the inorganic value (IV) to the organic value (OV) in the organic conceptual diagram, that is, "inorganic value (IV) / organic value (OV)". For the organic conceptual diagram, refer to, for example, "Organic Conceptual Diagram-Basics and Applications-" (Yoshio Koda, Sankyo Publishing, 1984).

The polar oil (component C) used in the present invention is not particularly limited, but is not particularly limited, but is glyceryl diisostearate, diisostearyl malate, tripropylene glycol pivalate, glyceryl tri2-ethylhexanoate, cetyl octanoate, lauric acid. Hexil, isopropyl myristate, octyl palmitate, isocetyl stearate, isopropyl isostearate, octyl isopalmitate, isodecyl isostearate, 2-ethylhexyl succinate, diethyl sebacate, cetyl ethylhexanate, 2-cyano-3,3- 2-Ethylhexyl diphenylacrylate, tripropylene glycol dipivalate, trimethylolpropane tri2-ethylhexanoate, pentaneerislit tetra2-ethylhexanoate, diethylhexyl naphthalin dicarboxylate, alkyl benzoate (C12-15), tri ( Caprylic capric acid) glycerin, di (capryl capric acid) propylene glycol, di2-ethylhexyl succinate, diisopropyl sebacate, jojoba oil, di lauroyl glutamate (phytosteryl / octyldodecyl), glyceryl triisostearate, triethylhexanoin, Dimerginolic acid (phytosteryl / behenyl), dimerginolic acid (phytosteryl / isostearyl / cetyl / stearyl / isostearyl / cetyl / stearyl / behenyl), isopropyl palmitate, macadamia nut fatty acid phytosteryl, tetra (bechenic acid / benzoic acid) / Ethylhexanoic acid) Examples thereof include pentaerythricyl, ethylhexyl palmitate, myristyl myristate, isodecyl neopentate, and oil-soluble ultraviolet absorbers.

The cosmetic of the present invention can be imparted with an ultraviolet protective effect by incorporating an oil-soluble ultraviolet absorber as part or all of the (C) polar oil. The oil-soluble ultraviolet absorber blended in the cosmetic of the present invention can be selected from those conventionally used in cosmetics. Specific examples include methoxycinnamic acid derivatives, salicylic acid derivatives, benzoyl derivatives, camphor derivatives, para-aminobenzoic acid derivatives, triazine derivatives, benzophenone derivatives, and polysilicone derivatives. More specifically, ethylhexyl methoxycinnamate, octocrylene, polyvinyl-15, t-butylmethoxydibenzoylmethane, ethylhexyltriazone, hexyl diethylaminohydroxybenzoylbenzoate, bisethylhexyloxyphenol methoxyphenyltriazine, oxybenzon-3, methylene Examples thereof include, but are not limited to, bisbenzotriazolyltetramethylbutylphenol, phenylbenzimidazole sulfonic acid, homosalate, and octyl salicylate (ethylhexyl salicylate). Further, the oil-soluble ultraviolet absorber can be blended in one kind or a combination of two or more kinds.

The blending amount of the polar oil (C component) in the cosmetic of the present invention is essential to be 3 to 30% by mass, preferably 4 to 25% by mass, and more preferably 5 to 20% by mass with respect to the total amount of the cosmetic. %, For example, 10 to 20% by mass. If the blending amount is less than 3% by mass, the effect of the polar oil blending cannot be sufficiently obtained, and if the blending amount exceeds 30% by mass, stickiness occurs after application and the unique feeling of use (collapse feeling) may be lost. be.

In addition to the above-mentioned essential ingredients (A), (B) and (C), the cosmetic of the present invention contains other ingredients that can be usually blended in cosmetics and external preparations for skin, as long as the effects of the present invention are not impaired. It can be blended arbitrarily.
Other optional components include, but are not limited to, oils (except polar oil (component C)), surfactants, thickeners (however, other than associative thickeners (component A)), and powder components. , Moisturizers, various medicinal ingredients, preservatives, antioxidants and the like.

Examples of the oil component other than the polar oil (C component) include non-polar oils such as silicone oil and hydrocarbon oil.
The surfactant is not particularly limited as long as it can be used for cosmetics and the like. In particular, a hydrophilic nonionic surfactant having an HLB value of 7 or more, preferably 10 or more is preferably used.

It is preferable to add a water-soluble thickener (however, other than the associative thickener (component A)) as the thickener because the emulsion stability of the cosmetic is further improved.

The water-soluble thickener may be any one that can be blended in cosmetics, and is, for example, a plant-based polymer such as agar, xanthan gum, arabic gum, carrageenan, pectin, quince seed (malmero), and algae colloid (brown algae extract). Molecules, microbial polymers such as dextran and purulan, animal polymers such as collagen, casein and gelatin, alginic acid polymers such as sodium alginate, vinyl polymers such as carboxyvinyl polymers (CARBOPOL, etc.), polyacrylic acid Examples thereof include acrylic polymers such as sodium, polyacrylamide, (acrylic acid / alkyl acrylate (C10-30) copolymer), and inorganic water-soluble polymers such as bentonite, aluminum magnesium silicate, and laponite.

As powder components, inorganic powders such as extender pigments (for example, talc, kaolin, sericite, white mica, synthetic mica, gold mica, red mica, black mica, lithia mica, vermiculite, magnesium carbonate, calcium carbonate, diatomaceous earth, silicic acid) Magnesium silicate, calcium silicate, aluminum silicate, barium silicate, strontium silicate, metal tungrate, silica, hydroxyapatite, zeolite, boron nitride, ceramics powder, etc.), organic powder (PMMA powder, nylon powder, etc.), Alternatively, an ultraviolet scattering agent (titanium oxide, zinc oxide, etc.) can be exemplified. Among them, talc, which is an extender pigment, has the effect of further improving the UV protection ability of cosmetics.

Examples of the moisturizer include polyhydric alcohols such as 1,3-butylene glycol, propanediol, and glycerin, sugar alcohols, and the like.

When a water-soluble ultraviolet absorber such as phenylbenzimidazole sulfonic acid is added to the cosmetic of the present invention, it is inevitably added in the form of a salt with a counterion, and the presence of the counterion is present (B). ) It may interact with the water-absorbent polymer to reduce the usability. Therefore, the cosmetic of the present invention includes an embodiment in which a water-soluble ultraviolet absorber is not blended, and even when blended, it is preferable to limit the blending amount to 0.5% by mass or less.

The viscosity of the cosmetic of the present invention is not particularly limited, but the value measured by a B-type viscometer at 30 ° C. is 10,000 mPa · s or more, preferably 20,000 mPa · s or more, and 200,000 mPa · s. Hereinafter, it is preferably 100,000 mPa · s or less.

The cosmetic of the present invention can be produced according to a method conventionally used for oil-in-water emulsified cosmetics. For example, it can be produced by separately mixing an aqueous component, an arbitrary powder component and an oily component, adding the powder component and the oily component to the aqueous component, and stirring and emulsifying.

The cosmetic of the present invention is characterized by having an appropriate richness at the time of application, and then having a fresh feeling of use (collapse feeling) such that it collapses and water overflows. It is preferable to provide it as a skin cosmetic product utilizing these characteristics, particularly as a skin care cosmetic product. The form of the cosmetic is not particularly limited, but it is preferably provided in the form of a cream or a milky lotion, for example.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, the blending amount is shown in% by mass.

An oil-in-water emulsified cosmetic (sample) was prepared according to the formulations shown in Tables 1 to 3 below. The following items were evaluated for the samples of each example.
(1) Stability (2) Unique feeling of use (collapse feeling) that collapses and overflows water
(3) Stickiness after application (4) Appearance

-Evaluation method (1) Stability After storing the samples of each example at 50 ° C. for 72 hours, the emulsified state was visually observed.
A ⁺ : Very good A: Good B: Normal C: Bad

(2) Feeling of collapse An answer as to whether or not a specialist panelist (10 women) will use each sample (cosmetics), apply it to the skin, and then feel the unique feeling of use (feeling of collapse) of the present invention. Evaluated based on.
A ⁺ : Answer that 9 or more out of 10 people feel A: Answer that 8 out of 10 people feel B: Answer that 5 to 7 out of 10 people feel C: Answer that 4 or less out of 10 people feel

(3) Stickiness after application We asked specialized panelists (10 women) to use each sample (cosmetics) and evaluated based on the answers as to whether or not they felt stickiness after application to the skin.
A ⁺ : 9 out of 10 responded that they did not feel sticky A: 8 out of 10 responded that they did not feel sticky B: 5-7 out of 10 responded that they did not feel sticky C: 10 respondents 4 or less of them answered that they did not feel sticky

(4) Appearance The appearance was visually observed immediately after the samples of each example were prepared, and the uniformity (presence or absence of whelks, etc.) was evaluated.
A ⁺ : Extremely uniform A: Uniform B: Normal C: Non-uniform (whelk is observed)

The cosmetics of the present invention (Examples 1 to 13) showed very satisfactory results in all the evaluation items of stability, collapse feeling, stickiness, and appearance. These evaluations were similar even when the type of associative thickener was changed (Examples 1 to 4) and when talc was removed from the formulation (Example 5). In Comparative Examples 1 and 2 (Table 1) in which the associative thickener was not blended with respect to these Examples, a unique feeling of use (collapse feeling) was not obtained. The same was true for Comparative Example 3 in which the same amount of polyglyceryl-6 caprylate, which was not an associative thickener, was blended. Further, Comparative Example 4 in which the amount of polyglyceryl-6 caprylate was increased in order to obtain a viscosity (37,000 mPa · s) equivalent to that of Example 1 (viscosity 36000 mPa · s (30 ° C., B-type viscometer)) was also the same, and was rather sticky. The SPF of the sample of Example 1 containing talc was improved as compared with the SPF of the sample of Example 5 containing no talc.

On the other hand, even in Comparative Example 5 (Table 2) in which the water-absorbent polymer was not blended, no “collapse feeling” was obtained, and in Comparative Example 6 in which the amount of the associative thickener was doubled, although a collapse feeling was obtained, stickiness occurred. rice field. Further, Comparative Example 7 in which the amount of the water-absorbent polymer compounded is small and the product (X × Y) of the water absorption rate and the compounding amount is less than 20, and the product (X × Y) of the water absorption rate and the compounding amount is 75. Even in Comparative Example 8 exceeding, no “feeling of collapse” was obtained.

In Table 1, in Example 2 using the (PEG-240 / decyltetradeceth-20 / HDI) copolymer as the associative thickener, the stability was slightly lower than that of the other associative thickeners. , (Acrylic acid / alkyl acrylate (C10-39)) was given the highest rating (A ⁺ ) by increasing the amount of the copolymer (Example 9 (Table 3)).

Even if the type of the water-absorbent polymer was changed or the blending amount of the polar oil was changed in the range of up to 30% by mass, all the properties intended by the present invention were good (Examples 10 to 13). However, when the blending amount of the polar oil exceeded 30% by mass, the stickiness after application became remarkable (Comparative Example 9).

Claims (8)

1. (A) Associative thickener,
   An oil-in-water emulsified cosmetic containing (B) a water-absorbent polymer and (C) a polar oil.
   The blending amount of the polar oil (C) is 3 to 30% by mass with respect to the total amount of cosmetics.
   An oil-in-water emulsified cosmetic according to the product (X × Y) of the water absorption rate (X) of the water-absorbent polymer (B) and the blending amount (Y mass%) thereof is in the range of 20 to 75. ..
2. The first aspect of the present invention, wherein the (B) water-absorbent polymer is at least one selected from the group consisting of (B-1) Acrylate crosspolymer-2-Na and (B-2) Na acrylate-grafted starch. Cosmetics.
3. The cosmetic according to claim 2, wherein the (B) water-absorbent polymer is (B-1) Acrylate cloth polymer-2-Na.
4. The (A) associative thickener is selected from the group consisting of (A-1) hydrophobically modified polyether urethane, (A-2) hydrophobically modified alkyl cellulose, and (A-3) polyacrylate crosspolymer-6. The cosmetic according to any one of claims 1 to 3, which is at least one kind.
5. The cosmetic according to claim 4, wherein the (A) associative thickener is (A-1) hydrophobically modified polyether urethane.
6. (A) The cosmetic according to claim 5, wherein the associative thickener is polyurethane-59.
7. The cosmetic according to any one of claims 1 to 6, further containing talc.
8. (C) The cosmetic according to any one of claims 1 to 7, wherein the polar oil contains an oil-soluble ultraviolet absorber.