HK1125054A - Skin cosmetic - Google Patents

Description

Skin cosmetic

Technical Field

The present invention relates to a skin cosmetic composition which contains beta-alanyl-L-histidine and/or a salt thereof (commonly known name: carnosine or a basic dipeptide), has excellent usability, and has excellent stability. Among them, the β -alanyl-L-histidine and/or a salt thereof are known as drugs effective in inhibiting skin damage/UV-induced immunity, reducing wrinkles, inhibiting parakeratosis, and shrinking pores.

Background

β -alanyl-L-histidine is called L-carnosine and is known to be widely distributed in skeletal muscle of various animals (non-patent document 1). The physiological function of the plant is not clear, but it is reported to have an antioxidant effect or a metal chelator effect.

Patent applications of β -alanyl-L-histidine as a cosmetic are both in japan and abroad, and the use of β -alanyl-L-histidine as a skin cosmetic having excellent cosmetic effects such as anti-wrinkle (patent document 1) and skin activation, revitalization, and whitening (patent document 2) is described.

Further, for the purpose of a drug, a patent has been filed which focuses on various pharmacological actions [ for example, a therapeutic agent for thermal injury (patent document 3), a therapeutic agent for eczematous skin diseases and drug eruptions (patent document 4), a therapeutic agent for senile pruritus (patent document 5), an antitumor agent (patent document 6), an antiulcer agent (patent document 7), an antitumor agent (patent document 8), a therapeutic agent for preventing liver diseases (patent document 9), an immunomodulator (patent document 10), and a prophylactic agent for osteoporosis (patent document 11) ].

PCT application (patent document 12) discloses use of β -alanyl-L-histidine in skin cosmetics or similar applications.

Patent document 1: EP2003-254760 publication

Patent document 2: japanese laid-open patent publication No. 2-221213

Patent document 3: japanese examined patent publication No. 60-45161

Patent document 4: japanese examined patent publication (Kokoku) No. 1-45451

Patent document 5: japanese examined patent publication (Kokoku) No. 1-49130

Patent document 6: japanese examined patent publication (Kokoku) No. 3-12045

Patent document 7: japanese examined patent publication (Kokoku) No. 3-5367

Patent document 8: japanese examined patent publication (Kokoku) No. 3-78368

Patent document 9: japanese examined patent publication (Kokoku) No. 4-62299

Patent document 10: japanese examined patent publication (Kokoku) No. 4-81966

Patent document 11: japanese examined patent publication No. 7-17505

Patent document 12: PCT/AU89/00422 publication

Non-patent document 1: biochemical dictionary (3 rd edition), Tokyo Chemicals, 1998, page 318.

As described above, β -alanyl-L-histidine and/or a salt thereof (INCI name: carnosine, basic dipeptide) are known as drugs effective in inhibiting skin damage/UV-induced immunity, reducing wrinkles, inhibiting parakeratosis, and shrinking pores.

However, since histidine is a basic amino acid, it exhibits basicity (pH8 or more) when added to an aqueous solution at a concentration at which the above-described effects are exhibited, and is not suitable as a weakly acidic skin cosmetic. Therefore, the original effect of β -alanyl-L-histidine and/or a salt thereof cannot be sufficiently applied to skin cosmetics.

On the other hand, thickeners are generally used in the preparation of skin cosmetics. However, in order to return the pH of a preparation made alkaline by blending β -alanyl-L histidine and/or a salt thereof to a weakly acidic region, if an acid such as citric acid or lactic acid is blended as a pH adjuster, the thickener exhibits a salt-like action depending on the alkaline property of β -alanyl-L histidine and/or a salt thereof and the acidic property of the acid, and if a thickener which does not normally have salt resistance, such as a carboxyvinyl polymer, an alkyl-modified carboxyvinyl polymer, or an acrylamide polymer, is used, there arises a problem in stability.

On the other hand, when succinoglycan, xanthan gum, or the like, which is known to be excellent in stability, is used as a thickener having salt resistance, there is a problem in use feeling such as tenderness or stickiness, and it is not suitable as a skin cosmetic.

Disclosure of Invention

The present inventors have conducted intensive studies with respect to the above problems, and as a result, have found that: the present inventors have completed the present invention by preparing a skin cosmetic in which (D) pH at 25 ℃ is 5.0 or more and less than 8.0 by combining (a) β -alanyl-L-histidine and/or a salt thereof, (B) a thickener comprising a microgel containing a specific synthetic polyelectrolyte, and (C) an inorganic acid and/or an organic acid, and thereby obtaining a skin cosmetic having a sufficient thickening effect, no sticky feeling, a delicate feeling in use, and excellent stability.

The invention aims to: a weak-acidic skin cosmetic is produced by combining a beta-alanyl-L-histidine and/or a salt thereof with an inorganic acid and/or an organic acid, characterized in that the beta-alanyl-L-histidine and/or a salt thereof and a thickener containing a specific microgel are selected from a large number of cosmetic thickeners, whereby various effects of the beta-alanyl-L-histidine and/or a salt thereof are exhibited to the maximum, and a skin cosmetic having excellent feeling in use and stability can be provided.

That is, the present invention aims to: when a carboxyvinyl polymer which is a thickener generally used in skin cosmetics or a polymer gel containing a synthetic polyelectrolyte produced by a homogeneous polymerization method or a reverse phase suspension polymerization method is used, a weakly acidic skin cosmetic which has never been used and is excellent in feeling of use and stability can be provided.

Namely, the present invention provides a skin cosmetic containing the following components (a), (B), and (C) and satisfying the condition (D).

(A) beta-alanyl-L-histidine and/or salts thereof

(B) A thickener comprising a microgel obtained by: in a composition comprising an organic solvent or an oil component as a dispersion medium and water as a dispersed phase, a water-soluble ethylenically unsaturated monomer is dissolved in the dispersed phase, and radical polymerization is carried out in the dispersed phase.

(C) Inorganic and/or organic acids

(D) The skin cosmetic has pH of 5.0 or more and less than 8.0 at 25 deg.C

The present invention also provides the skin cosmetic, wherein the microgel of (B) is obtained by: the radical polymerization is carried out under the condition that a composition which takes an organic solvent or an oil component as a dispersion medium and water as a dispersion phase forms a single-phase microemulsion or a fine W/O emulsion through a surfactant.

The present invention further provides the skin cosmetic, wherein the microgel of the component (B) has an apparent viscosity at a shear rate of 1.0 second at 0.5 mass% and 25 ℃ in an aqueous dispersion^-1The lower value is 10000 mPas or more.

The present invention further provides the skin cosmetic, wherein the microgel of the component (B) has a 0.5 mass% and an apparent viscosity at a shear rate of 1.0 second in a 25 ℃ ethanol dispersion^-1The lower value is 10000 mPas or more.

The present invention further provides the skin cosmetic composition, wherein the microgel of the component (B) has a dynamic elastic modulus of G' (storage elastic modulus) > G "(loss elastic modulus) in a range of 0.5% by mass or less of strain and a frequency of 0.01 to 10Hz in a 25 ℃ aqueous dispersion or an ethanol dispersion.

The present invention also provides the skin cosmetic composition, wherein the water-soluble ethylenically unsaturated monomer of the above (B) is a dialkylacrylamide represented by the general formula (1) and an ionic acrylamide derivative represented by the general formula (2) or (3).

General formula (1)

[ chemical formula 1]

(R₁Represents H or methyl, R₂And R₃Each independently represents a methyl group, an ethyl group, a propyl group, or an isopropyl group);

general formula (2)

[ chemical formula 2]

(R₄And R₅Each independently represents H or methyl, R₆Represents a linear or branched alkyl group having 1 to 6 carbon atoms, X represents a metal ion, NH₃Amine compounds);

general formula (3)

[ chemical formula 2]

(R₇Represents H or methyl, R₈Represents H or a linear or branched alkyl group having 1 to 6 carbon atoms, R₉Represents a linear or branched alkyl group having 1 to 6 carbon atoms, R₁₀、R₁₁、R₁₂Represents a methyl group or an ethyl group, and Y represents an anionic counterion).

The present invention further provides the skin cosmetic, wherein the amount of the component (a) is 0.1 to 3.0% by mass based on the total amount of the skin cosmetic, the amount of the component (B) is 0.1 to 5.0% by mass based on the total amount of the skin cosmetic, and the amount of the component (C) is 0.01 to 1.0% by mass based on the total amount of the skin cosmetic.

The present invention also provides the skin cosmetic, wherein the inorganic acid or organic acid of the component (C) is one or two or more selected from phosphoric acid, lactic acid and citric acid.

Detailed Description

The present invention is described in detail below.

< ingredient (A) >

The beta-alanyl-L-histidine of component (A) is commercially available as a reagent and can be easily obtained. It can also be synthesized by a known method.

In the present invention, beta-alanyl-L-histidine and/or a salt thereof is used.

The salt thereof is not particularly limited, and examples of the inorganic salt include hydrochloride, sulfate, phosphate, hydrobromide, sodium salt, potassium salt, magnesium salt, calcium salt, and ammonium salt. The organic salt is selected from acetate, lactate, maleate, fumarate, tartrate, citrate, methanesulfonate, p-toluenesulfonate, triethanolamine salt, diethanolamine salt, amino acid salt, etc.

The β -alanyl-L-histidine can be prepared into an inorganic salt or an organic salt by a known method.

Commercially available products of β -alanyl-L-histidine are: dragosine 2/060700 (manufactured by Symrise), Oripeptide CNS (manufactured by Orient Stars LLC), etc. Further, carnosine (2HCL) (manufactured by Exsymol) and the like are commercially available as a salt of β -alanyl-L-histidine.

The amount of component (a) blended is preferably 0.1 to 3.0 mass% with respect to the total amount of the skin cosmetic. When the amount is less than 0.1% by mass, the effect of β -alanyl-L-histidine and/or a salt thereof cannot be sufficiently exhibited. On the other hand, the addition of more than 3.0% by mass does not enhance the effect.

< ingredient (B) >

The microgel-containing thickener of component (B) may be a synthetic polymeric microgel, which is obtained by: in a composition comprising an organic solvent or an oil component as a dispersion medium and water as a dispersed phase, a water-soluble ethylenically unsaturated monomer is dissolved in the dispersed phase, and radical polymerization is carried out in the dispersed phase.

That is, a polymer microgel generally prepared by a so-called reverse phase emulsion polymerization method is applied to a thickener, and the polymerization method and mechanical properties are different from those of a thickener containing a synthetic polymer obtained by a homogeneous polymerization system disclosed in Japanese patent laid-open No. 2001-114641.

Microgels are microparticles of synthetic polyelectrolytes prepared by reverse phase microemulsion polymerization. The thickener containing microgel used in the invention is swelled in water, ethanol or a water-ethanol mixed solution, and can provide a high-viscosity solution which is visually observed to be uniform in appearance.

In the present invention, the polymerization system of the microgel used as the thickener is different from the conventional homogeneous polymerization system for preparing a synthetic polymer as the thickener. For example, the synthetic polymer obtained by the homogeneous polymerization system disclosed in Japanese patent application laid-open No. 2001-114641 is not a microgel used in the present invention, and it is necessary to pulverize the polymer into powder for incorporation into cosmetics after the polymerization of the synthetic polymer. The gel of the synthetic polymer is conspicuous and may cause problems in appearance.

The microgel used in the present invention is polymerized by a heterogeneous polymerization system. The obtained synthetic polymer is fine polymer gel, i.e. microgel, and can be made into powder without re-pulverization when being mixed in cosmetic, and has excellent thickening effect and excellent feeling in use, and the appearance of cosmetic is also preferable.

As for the reverse phase emulsion polymerization method of polymers, japanese patent No. 1911623 discloses: the water-swellable polymer using acrylic acid is prepared by reverse phase polymerization and applied as a thickener technique, but this is to improve the disadvantages of the currently used carboxyvinyl polymer, unlike the microgel used in the present invention.

Further, jp 9-12613 a discloses that microgel particles of a water-absorbent resin are made to have a size of at least a certain value so as to be suitable for use in diapers or sanitary products, but this is not a technique applicable to cosmetic thickeners, and the microgel used in the present invention is completely different.

The thickener used in the present invention is prepared in a reverse phase emulsion polymerization method (Japanese patent laid-open No. 2004-114641). That is, in a composition having an organic solvent or an oil component as a dispersion medium and water as a dispersed phase, a water-soluble ethylenically unsaturated monomer is dissolved in the dispersed phase, and radical polymerization is performed in the dispersed phase to prepare the polymer. The polymerized microgel may be washed and dried without pulverization.

It is particularly preferred to prepare the microgel-containing thickener under conditions such that the polymerization system in the reverse phase emulsion polymerization forms a single-phase microemulsion or a fine W/O emulsion by using a suitably selected surfactant adjusted to the hydrophilic-hydrophobic balance (HLB).

A single-phase microemulsion refers to a state in which the surface tension between oil and water is extremely small in a state in which an oil phase and an aqueous phase are thermodynamically stable. The minute W/O emulsion is thermodynamically unstable, but in the speed theory, oil and water exist stably in the form of the minute W/O emulsion. Generally, the particle size of the inner aqueous phase of the fine W/O emulsion is about 10 to 100 nm. These conditions are determined only by the composition and temperature of the system and are not influenced by mechanical stirring conditions and the like.

The composition constituting the polymerization system comprises a dispersion medium (constituting an external phase) containing an organic solvent or an oil component immiscible with water, and a dispersed phase (constituting an internal phase) containing water. Preferred organic solvents are: alkanes such as pentane, hexane, heptane, octane, nonane, decane, undecane, and the like; cycloalkanes such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane; aromatic and cyclic hydrocarbons such as benzene, toluene, xylene, decalin, naphthalene, etc.

Preferred oils are nonpolar oils such as paraffin oil.

The water-soluble ethylenically unsaturated monomer is dissolved in water as a dispersed phase, followed by mixing with an organic solvent or an oil component as a dispersion medium, heating to a desired temperature, and then adding a polymerization initiator to the aqueous phase to carry out polymerization.

In general, in the heterogeneous polymerization method, it is known that the physical properties of the polymer to be produced are different depending on the stirring conditions during the polymerization. This is because the emulsified system is not in a thermodynamically stable state, and thus the shape and size of the emulsified particles change under the stirring conditions. The invention discovers that: these problems can be avoided by carrying out the polymerization in a fine W/O emulsion region that exists near a thermodynamically stable single phase microemulsion region or near stable single phase region. Specifically, by adjusting the composition of the polymerization system (the type of organic solvent, the HLB of the surfactant), the single-phase microemulsion or the fine W/O emulsion region appears near the optimum polymerization temperature of a polymerization initiator for general thermal polymerization or redox polymerization, and then the polymer is polymerized in a fine aqueous phase (water droplets), whereby a microgel having a high thickening effect can be obtained.

On the other hand, in conventional polymer thickeners produced by suspension polymerization (for example, the method disclosed in Japanese unexamined patent application, first publication No. 2001-1146641), it is difficult to control the particle size of water droplets during polymerization, and it is difficult to obtain a fine microgel.

The water-soluble ethylenically unsaturated monomer is preferably used in combination with a nonionic monomer and an ionic monomer (an anionic monomer or a cationic monomer).

The nonionic monomer is preferably a dialkylacrylamide represented by the following general formula (1).

The ionic monomer is preferably an anionic acrylamide derivative represented by the following general formula (2) or a cationic acrylamide derivative represented by the following general formula (3).

General formula (1)

[ chemical formula 4]

(R₁Represents H or methyl, R₂And R₃Each independently represents a methyl group, an ethyl group, a propyl group, or an isopropyl group);

general formula (2)

[ chemical formula 5]

(R₄And R₅Each independently represents H or methyl, R₆Represents a linear or branched alkyl group having 1 to 6 carbon atoms, X represents a metal ion, NH₃The amine compound is, for example, a metal ion of Li, Na, or K, and the amine compound is triethanolamine or triisopropanolamine).

General formula (3)

[ chemical formula 6]

(R₇Represents H or methyl, R₈Represents H or a linear or branched alkyl group having 1 to 6 carbon atoms, R₉Represents a linear or branched alkyl group having 1 to 6 carbon atoms, R₁₀、R₁₁、R₁₂Represents a methyl group or an ethyl group, Y represents an anionic counter ion, for example, a negative counter ion such as Cl or Br)

Particularly preferred dialkylacrylamides are dimethylacrylamide, diethylacrylamide.

Particularly preferred ionic acrylamide derivatives are 2-acrylamido 2-methylpropanesulfonic acid and salts thereof.

A particularly preferred cationic acrylamide derivative is N, N-dimethylaminopropylacrylamide methyl chloride.

In the polymerization system of the nonionic monomer and the ionic monomer, the monomer composition ratio (charge ratio of the polymerization system) can be appropriately determined depending on the monomer composition ratio of the objective microgel. The monomer composition ratio of the microgel is about the same as the feed ratio to the polymerization system. The charge ratio (molar ratio) of the nonionic monomer to the ionic monomer in the polymerization system is usually in the range of 0.5:9.5 to 9.5:0.5, preferably 1:9 to 9:1, more preferably 7:3 to 9: 1. The optimum ratio is nonionic monomer to ionic monomer ═ 8: 2.

The water soluble ethylenically unsaturated monomers described above are optionally selected and polymerized to form the thickeners of the present invention. Particularly preferred thickeners are microgels of binary copolymers obtained by copolymerizing dimethyl acrylamide and 2-acrylamido-2-methylpropanesulfonic acid among water-soluble ethylenically unsaturated monomers. In this case, a thickener which can exhibit excellent thickening effect and feeling in use can be obtained by self-crosslinking without using a crosslinking monomer. A crosslinking monomer may also be used, and in this case, a crosslinking monomer represented by the general formula (4) is preferable, and methylenebisacrylamide is particularly preferable.

General formula (4)

[ chemical formula 7]

(R₁₃And R₁₇Represents H or methyl, R₁₄And R₁₆represents-O-or-NH-, R₁₅Represents a linear or branched alkyl group having 1 to 6 carbon atoms, or(n＝4-100))。

In order to dissolve the water-soluble ethylenically unsaturated monomer in the dispersed phase and polymerize the microgel preferred in the present invention, it is necessary to select an optimum external oil component or organic solvent, and surfactant, respectively. With respect to the composition of the polymerization system, the present inventors have prepared a phase diagram of hydrophilic-hydrophobic balance (HLB) of the nonionic surfactant, expressed a cloud point preparation polymerization system at a temperature suitable for thermal radical polymerization, and prepared a state of forming a single-phase microemulsion or a fine W/O emulsion at a normal thermal radical polymerization temperature, thereby obtaining a microgel as a thickener having preferable characteristics.

Preferred surfactants are: polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene hexyldecyl ether, polyoxyethylene isostearyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene behenyl ether, polyoxyethylene cholesteryl ether, polyoxyethylene hydrogenated castor oil, sorbitan fatty acid ester, mono-fatty acid glyceride, tri-fatty acid glyceride, polyglyceryl fatty acid ester, polyoxyethylene glyceryl isostearate, polyoxyethylene glyceryl triisostearate, polyoxyethylene glyceryl monostearate, polyoxyethylene glyceryl distearate, polyoxyethylene glyceryl tristearate, and the like.

These surfactants may be appropriately combined, adjusted to a desired HLB, and added to the polymerization system.

In the microgel obtained by copolymerizing a dialkylacrylamide and an acrylamide ionic monomer, a spontaneous crosslinking reaction proceeds, and particularly, a chemically self-crosslinked microgel can be obtained without copolymerizing a polyfunctional crosslinking monomer as a third component, and a thickener particularly preferable in the present invention is formed.

The functional crosslinking monomer of the third component is not essential, but addition of the monomer copolymerization may also synthesize the microgel used in the present invention. The polyfunctional crosslinking monomer is preferably a monomer represented by the general formula (6), and may be crosslinked by using one or two or more crosslinking monomers represented by the general formula (6). These crosslinkable monomers must effectively obtain a crosslinked structure in a polymerization system of a dialkylacrylamide and an ionic acrylamide derivative.

Preferred crosslinking monomers are, for example: ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyoxyethylene diacrylate, polyoxyethylene dimethacrylate, diethylene glycol dimethacrylate, trimethylolpropane triacrylate, N '-methylenebisacrylamide, N' -ethylenebisacrylamide, triallyl isocyanurate, pentaerythritol dimethacrylate, etc., and one or two or more selected from them may be used. In the present invention, N' -methylenebisacrylamide is particularly preferably used.

In the copolymer used as the thickener in the present invention, the content of the 2-acrylamido-2-methylpropanesulfonic acid unit and the dialkylacrylamide unit is usually 0.5:9.5 to 9.5:0.5, preferably 1:9 to 9:1, and more preferably 3:7 to 1:9 in terms of the molar ratio of the 2-acrylamido-2-methylpropanesulfonic acid unit to the dialkylacrylamide unit. The most preferred ratio is 2:8 of 2-acrylamido-2-methylpropanesulfonic acid units to dialkylacrylamide units. The viscosity of the thickener of the present invention is due to molecular chain extension by electrostatic repulsion of the strongly dissociating group sulfonyl group, a self-crosslinking reaction of the dialkylacrylamide, or a crosslinked structure by the crosslinkable monomer, but the molecular chain extension does not occur sufficiently because the content of the 2-acrylamido-2-methylpropanesulfonic acid unit or the salt thereof is less than 5 mol% relative to the dialkylacrylamide unit, and thus a sufficient viscosity cannot be obtained.

The amount of the crosslinkable monomer to be used is preferably in the range of 0.0001 to 2.0 mol% based on the total mole number of the 2-acrylamido-2-methylpropanesulfonic acid or a salt thereof and the dialkylacrylamide. The thickener prepared at less than 0.0001 mol% may not exhibit the crosslinking effect. When the amount is more than 2 mol%, the crosslinking density is too high, and the microgel is not sufficiently swollen, so that the thickening effect cannot be exerted.

The molecular weight of the microgel used in the present invention is about 10 to 500 million weight average molecular weight (in terms of PEG: measured by GPC), and the molecular weight is adjusted as a thickener according to the viscosity obtained.

The microgel obtained from the above polymerization method has all the rheological properties of the following (1) to (3). The thickener containing the microgel can be obtained by the above-mentioned polymerization method, and is preferably used as a thickener.

(1) An aqueous dispersion of microgel at 0.5% (mass percent) had an apparent viscosity at a shear rate of 1.0s^-1The lower value is 10000 mPas or more.

(2) 0.5% (mass percent) ethanol dispersion of microgel has apparent viscosity at shear rate of 1.0s^-1The lower value is 5000 mPas or more.

(3) The dynamic elastic modulus of the microgel in 0.5% (mass percent) aqueous dispersion or ethanol dispersion is G '> G' within the range of strain of 1% or less and frequency of 0.01-10 Hz.

The apparent viscosity of the aqueous or alcoholic dispersion of the microgel was measured at a measurement temperature of 25 ℃ and a shear rate of 1s using a cone-plate rheometer (MCR-300, manufactured by Paar Rhysica)^-1Viscosity of (b).

The dynamic elastic modulus is a value of storage elastic modulus (G ') and loss elastic modulus (G') measured at a measurement temperature of 25 ℃ and a strain of 1% or less in a frequency range of 0.1 to 10Hz by using the same measuring apparatus.

The microgel used in the present invention can be isolated in a powder state after polymerization via a simple precipitation purification step. The microgel separated into powder is easily dispersed in water or ethanol or a mixed solvent of water and ethanol, and rapidly swells to play the function of a thickening agent.

By selecting the ionic monomer copolymerized into the microgel as a strongly acidic monomer (for example, a monomer containing a sulfonic acid residue), it is possible to thicken an acidic agent which has not been possible to thicken in a conventional carboxyvinyl polymer.

The skin cosmetic of the present invention is prepared by blending the microgel as a thickener in a skin cosmetic base. The amount of the thickener is appropriately determined according to the target skin cosmetic, and is not limited thereto. From the viewpoint of usability, the amount is preferably from 0.01 to 10% by mass, more preferably from 0.1 to 5% by mass.

< ingredient (C) >

The inorganic acid and/or organic acid of the component (C) is described. The inorganic acid and/or the organic acid used in the present invention may be used as a pH adjuster. Phosphoric acid, lactic acid, citric acid, etc., and one or two or more thereof may be arbitrarily selected. When the skin cosmetic is prepared into an aqueous base or an oil-in-water emulsion composition, the pH of the whole composition is adjusted to 5.0 or more and less than 8.0. If the pH is less than 5.0, the acidity is too strong, and thus the cosmetic is not suitable for skin. If the pH is higher than 8.0, the alkalinity is too high, and the cosmetic is not suitable for skin.

The present invention is an effect of adjusting the pH of a skin cosmetic to 8.0 or more by the component (a) comprising a basic amino acid, and the pH is reduced by the component (C) comprising an inorganic acid and/or an organic acid, to adjust the pH to a region of the most preferable pH of the skin cosmetic. The pH range is the condition (D) (the pH of the skin cosmetic at 25 ℃ is 5.0 or more but less than 8.0).

When an acid such as citric acid is added to a skin cosmetic in order to adjust the pH of the skin cosmetic to 5.0 or more and less than 8.0 by incorporating β -alanyl-L-histidine and/or a salt thereof, a thickener thickened by charge repulsion of a carboxyvinyl polymer, polyacrylamide, or the like causes a problem in stability due to the action of β -alanyl-L-histidine and/or a salt thereof to increase the pH and the action of an acid to decrease the pH, resulting in a thickening and separation.

On the other hand, nonionic thickeners such as xanthan gum and hydroxyethyl cellulose do not have a stability problem, but have poor affinity with the skin, no delicate feeling, sticky feeling, and a problem in terms of usability.

However, even when β -alanyl-L-histidine and/or a salt thereof, and an inorganic acid and/or an organic acid are blended together with the thickener of component (B) used in the present invention to adjust the content to 5.0 or more and less than 8.0, which is preferable for skin cosmetics, the stability of the thickening effect does not become a problem, and the thickener has good affinity with the skin, a delicate feeling, a penetrating feeling, no sticky feeling, and good usability.

The skin cosmetic of the present invention contains the above-mentioned components (a) to (C) and satisfies the condition (D), and thus can provide a skin cosmetic which is excellent in long-term stability, good in skin affinity, delicate and permeable feeling, free from sticky feeling and excellent in feeling of use, in combination with the component (a) which is known to be a drug effective in suppressing skin damage/UV-induced immunity, anti-wrinkle, parakeratosis, pore shrinkage, and the like.

The skin cosmetic of the present invention may contain, in addition to the essential components described above, other components used in ordinary cosmetics as needed, for example: the skin care composition comprises a powder component, liquid grease, solid grease, wax, hydrocarbon, higher fatty acid, higher alcohol, ester, organic silicon, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, a humectant, a water-soluble polymer, a thickener, a coating agent, an ultraviolet absorbent, a metal ion blocking agent, lower alcohol, polyhydric alcohol, sugar, amino acid, organic amine, a polymer emulsion, a pH regulator, a skin nutrient, vitamin, an antioxidant auxiliary agent, spice, water and the like, and is prepared according to a conventional method according to a target dosage form. The skin cosmetic of the present invention can be prepared by mixing the above essential components and any one or two or more of the following components.

Examples of the powder components include: inorganic powders (e.g., talc, kaolin, mica, sericite, muscovite, phlogopite, synthetic mica, lepidolite, biotite, vermiculite, magnesium carbonate, calcium carbonate, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, strontium silicate, tungstic acid metal salt, magnesium, silica, zeolite, barium sulfate, calcined calcium sulfate (plaster of Paris), calcium phosphate, fluorapatite, hydroxyapatite, ceramic powder, metal soaps (e.g., zinc myristate, calcium palmitate, aluminum stearate), boron nitride, etc.); organic powders (e.g., polyamide resin powder (nylon powder), polyethylene powder, polymethyl methacrylate powder, polystyrene powder, copolymer resin powder of styrene and acrylic acid, benzoguanamine resin powder, polytetrafluoroethylene powder, cellulose powder, etc.); inorganic white pigments (e.g., titanium dioxide, zinc oxide, etc.); inorganic red pigments (e.g., iron oxide (red iron oxide), iron titanate, and the like); inorganic brown pigments (e.g., gamma-iron oxide); inorganic yellow pigments (e.g., yellow iron oxide, yellow soil, etc.); inorganic black pigments (e.g., black iron oxide, lower titanium oxide, etc.); inorganic violet pigments (e.g., manganese violet and cobalt violet); inorganic green pigments (e.g., chromium oxide, chromium hydroxide, cobalt titanate, etc.); inorganic blue pigments (e.g., ultramarine blue, navy blue, etc.), pearl pigments (e.g., mica coated with titanium oxide, bismuth oxychloride coated with titanium oxide, talc coated with titanium oxide, mica coated with colored titanium oxide, bismuth oxychloride, fish scale foil, etc.); metal powder pigment (for example, aluminum powder, copper powder, etc.): organic pigments such as zirconium, barium or aluminum lakes (for example, organic pigments such as red 201, red 202, red 204, red 205, red 220, red 226, red 228, red 405, orange 203, orange 204, yellow 205, yellow 401 and blue 404, and red 3, red 104, red 106, red 227, red 230, red 401, red 505, orange 205, yellow 4, yellow 5, yellow 202, yellow 203, green 3 and blue 1); natural dyes (e.g., chlorophyll, beta-carotene, etc.), and the like.

Examples of the liquid oils and fats include avocado oil, camellia oil, turtle oil (タ - トル oil), macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg butter, sesame oil, almond oil, wheat germ oil, camellia oil, castor oil, linseed oil, sunflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, coconut oil, rice bran oil, paulownia oil (シナギリ oil), jatropha oil, jojoba oil, germ oil, triglycerin, and the like.

Examples of the solid fat and oil include: cocoa butter, coconut oil, hydrogenated coconut oil, palm kernel oil, wood wax kernel oil, hydrogenated oil, wood wax, hydrogenated castor oil, and the like.

Examples of waxes are: beeswax, candelilla wax, cotton wax, carnauba wax, bay wax, insect wax, spermaceti wax, montan wax, rice bran wax, lanolin, kapok wax, lanolin acetate, liquid lanolin, sucrose wax, isopropyl lanolin fatty acid ester, hexyl laurate, reduced lanolin, jojoba wax, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol acetate, POE cholesterol ether, lanolin fatty acid polyglycol ester, POE hydrogenated lanolin alcohol ether, and the like.

Examples of the hydrocarbon oil include: liquid paraffin, ceresin, squalane, pristane, paraffin, ceresin, squalene, vaseline, microcrystalline wax, etc.

Examples of higher fatty acids include: lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, undecylenic acid, tall oil fatty acid, isostearic acid, linoleic acid, linolenic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and the like.

Examples of higher alcohols are: linear alcohols (e.g., lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, cetostearyl alcohol, etc.); branched alcohols (e.g., monostearyl glyceryl ether (batyl alcohol), 2-decyltetradecyl alcohol, lanolin alcohol, cholesterol, phytosterols, hexyldodecanol, isostearyl alcohol, octyldodecyl alcohol, etc.), etc.

Examples of ester oils include: isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, 12-hydroxycholesteryl stearate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid ester, N-alkylglycol monoisostearate, neopentyl glycol dihexanoate, diisostearyl malate, di-2-heptylundecyl glyceride, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, pentaerythritol tetra-2-ethylhexanoate, glycerol tri-2-ethylhexanoate, glyceryl monostearate, glyceryl stearate, Tricaprylin, triisopalmitate, triisostearate trimethylolpropane, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, trimyristin, tri-2-heptylundecanoate, ricinoleic acid methyl ester, oleic acid oil, acetyl glycerol, 2-heptylundecyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, triethyl citrate, and the like.

Examples of the silicone oil include: chain polysiloxanes (e.g., polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane, etc.); cyclic polysiloxanes (e.g., octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, etc.), silicone resins forming a three-dimensional network structure, silicone rubbers, various modified polysiloxanes (e.g., amino-modified polysiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, fluorine-modified polysiloxane, etc.), and the like.

Examples of the anionic surfactant include fatty acid soaps (e.g., sodium laurate, sodium palmitate, etc.); higher alkyl sulfate ester salts (e.g., sodium lauryl sulfate, potassium lauryl sulfate, etc.); alkyl ether sulfate salts (e.g., POE-triethanolamine lauryl sulfate, POE-sodium lauryl sulfate, etc.); n-acyl sarcosines (e.g., sodium lauroyl sarcosinate, etc.); higher fatty acid amide sulfonates (e.g., sodium N-myristoyl-N-methyltaurate, sodium coconut fatty acid methyltaurate, sodium lauryl methyltaurate, etc.); phosphate ester salts (POE-oleyl ether sodium phosphate, POE-stearyl ether phosphoric acid, etc.); sulfosuccinates (e.g., sodium di-2-ethylhexyl sulfosuccinate, sodium monolauroyl monoethanolamide ethanolamide polyoxyethylene sulfosuccinate, sodium lauryl polypropylene glycol sulfosuccinate, and the like); alkyl benzene sulfonates (e.g., linear sodium dodecylbenzene sulfonate, linear triethanolamine dodecylbenzene sulfonate, linear dodecylbenzene sulfonic acid, etc.); higher fatty acid ester sulfate salts (e.g., sodium hydrogenated coconut fatty acid glyceride sulfate); n-acyl glutamate) such as monosodium N-lauroyl glutamate, disodium N-stearoyl glutamate, monosodium N-myristoyl-L-glutamate, etc.); sulfated oils (e.g., turkey red oil), and the like; POE-alkyl ether carboxylic acids; POE-alkyl allyl ether carboxylate; an alpha-olefin sulfonate; higher fatty acid ester sulfonates; salts of dihydric alcohol sulfuric acid ester; higher fatty acid alkylolamide sulfate salts; lauroyl monoethanolamide sodium succinate; n-palmitoyl aspartic acid di (triethanolamine); sodium tyrosine, and the like.

Examples of the cationic surfactant include: alkyltrimethylammonium salts (e.g., stearyltrimethylammonium chloride, lauryltrimethylammonium chloride, etc.); alkylpyridinium salts (e.g., cetylpyridinium chloride, etc.); distearyldimethylammonium chloride dialkyldimethylammonium salts; poly (N, N' -dimethyl-3, 5-methylenepiperidinium) chloride; alkyl quaternary ammonium salts; alkyl dimethyl benzyl ammonium salts; an alkylisoquinolinium salt; a dialkyl morpholinium salt; POE-alkylamine; an alkylamine salt; polyamino fatty acid derivatives; a pentanol fatty acid derivative; benzalkonium chloride; benzethonium chloride, and the like.

Examples of amphoteric surfactants are: imidazoline-based amphoteric surfactants (e.g., 2-undecyl-N, N, N- (hydroxyethylcarboxymethyl) -2-imidazoline sodium, 2-cocoyl-2-imidazolinium hydroxide-1-carboxyacetoxy 2 sodium salt, etc.); betaine-type surfactants (e.g., 2-heptadecyl-N-carboxymethyl-N-hydroxyethyl imidazolinium betaine, lauryl dimethylaminoacetic acid betaine, alkyl betaine, amidobetaine, thiobetaine, etc.), and the like.

Examples of the hydrophilic nonionic surfactant include: polyglycerol fatty acid esters such as hexaglycerol monolaurate (HLB14.5), hexaglycerol monomyristate (HLB11), hexaglycerol monostearate (HLB9.0), hexaglycerol monooleate (HLB9.0), decaglycerol monolaurate (HLB15.5), decaglycerol monomyristate (HLB14.0), decaglycerol monostearate (HLB12.0), decaglycerol monoisostearate (HLB12.0), decaglycerol monooleate (HLB12.0), decaglycerol distearate (HLB9.5), and decaglycerol diisostearate (HLB 10.0).

Polyoxyethylene glycerin fatty acid esters such as polyoxyethylene monostearate (hereinafter abbreviated as POE) (5) glycerin (HLB9.5), POE monostearate (15) glycerin (HLB13.5), POE monooleate (5) glycerin (HLB9.5), POE monooleate (15) glycerin (HLB14.5), and the like.

Polyoxyethylene sorbitan fatty acid esters such as POE (20) sorbitan monostearate (HLB16.9), POE (20) sorbitan monopalmitate (HLB15.6), POE (20) sorbitan monostearate (HLB14.9), POE (6) sorbitan monostearate (HLB9.5), POE (20) sorbitan tristearate (HLB10.5), POE (20) sorbitan monoisostearate (HLB15.0), POE (20) sorbitan monooleate (HLB15.0), POE (6) sorbitan monooleate (HLB10.0), and POE (20) sorbitan trioleate (HLB 11.0).

Polyoxyethylene sorbitan fatty acid esters such as POE (6) monolaurate sorbitol ester (HLB15.5), POE (60) tetrastearate sorbitol ester (HLB13.0), POE (30) tetraoleate sorbitol ester (HLB11.5), POE (40) tetraoleate sorbitol ester (HLB12.5), POE (60) tetraoleate sorbitol ester (HLB14.0), and the like.

Polyoxyethylene lanolin/lanolin alcohol/beeswax derivatives such as POE (10) lanolin (HLB12.0), POE (20) lanolin (HLB13.0), POE (30) lanolin (HLB15.0), POE (5) lanolin alcohol (HLB12.5), POE (10) lanolin alcohol (HLB15.5), POE (20) lanolin alcohol (HLB16.0), POE (40) lanolin alcohol (HLB17.0), and POE (20) sorbitol beeswax (HLB 9.5).

Polyoxyethylene castor oil/hydrogenated castor oil such as POE (20) castor oil (HLB10.5), POE (40) castor oil (HLB12.5), POE (50) castor oil (HLB14.0), POE (60) castor oil (HLB14.0), POE (20) hydrogenated castor oil (HLB10.5), POE (30) hydrogenated castor oil (HLB11.0), POE (40) hydrogenated castor oil (HLB13.5), POE (60) hydrogenated castor oil (HLB14.0), POE (80) hydrogenated castor oil (HLB16.5), POE (40) hydrogenated castor oil (100) hydrogenated castor oil (HLB16.5), and the like.

Polyoxyethylene sterol/hydrogenated sterols such as POE (5) phytosterol (HLB9.5), POE (10) phytosterol (HLB12.5), POE (20) phytosterol (HLB15.5), POE (30) phytosterol (HLB18.0), POE (25) phytostanol (HLB14.5), and POE (30) cholestanol (HLB 17.0).

POE (2) lauryl ether (HLB9.5), POE (4.2) lauryl ether (HLB11.5), POE (9) lauryl ether (HLB14.5), POE (5.5) cetyl ether (HLB10.5), POE (7) cetyl ether (HLB11.5), POE (10) cetyl ether (HLB13.5), POE (10) cetyl ether (HLB15.5), POE (20) cetyl ether (HLB17.0), POE (23) cetyl ether (HLB18.0), POE (4) stearyl ether (HLB9.0), POE (20) stearyl ether (HLB18.0), POE (7) oleyl ether (HLB10.5), POE (10) oleyl ether (HLB14.5), POE (15) oleyl ether (HLB16.0), POE (20) oleyl ether (17.0), POE (50) oleyl ether (HLB18.0), oleyl ether (HLB 10) oleyl ether (HLB 10.10), POE (HLB) oleyl ether (HLB14.5), POE (15) oleyl ether (HLB16.0), POE (HLB) alkyl) (HLB 3.35-C15), POE (HLB) alkyl (HLB 3.35) alkyl (HLB 26.5), POE (HLB 18.10) lauryl ether (HLB 18.10) alkyl (HLB) ether (HLB18.0), POE (HLB 3) alkyl (HLB) ether (HLB 3.10, polyoxyethylene alkyl ethers such as POE (10) (C12-C15) alkyl ether (HLB15.5), POE (5) secondary alkyl ether (HLB10.5), POE (7) secondary alkyl ether (HLB12.0), POE (9) alkyl ether (HLB13.5), and POE (12) alkyl ether (HLB 14.5).

Polyoxyethylene polyoxypropylene alkyl ethers such as polyoxyethylene (hereinafter abbreviated as POE) (1) polyoxypropylene (hereinafter abbreviated as POP) (4) cetyl ether (HLB9.5), POE (10) POP (4) cetyl ether (HLB10.5), POE (20) POP (8) cetyl ether (HLB12.5), POE (20) POP (6) decyltetradecyl ether (HLB11.0), and POE (30) POP (6) decyltetradecyl ether (HLB 12.0).

Polyethylene glycol fatty acid esters such as polyethylene glycol monolaurate (hereinafter referred to as PEG) (10) (HLB12.5), PEG (10) (HLB11.0), PEG (25) (HLB15.0), PEG (40) (HLB17.5), PEG (45) (HLB18.0), PEG (55) (HLB18.0), PEG (10) (HLB11.0), PEG (HLB16.5), PEG (HLB 9.5).

Polyoxyethylene isostearate glycerides such as PEG (8) isostearate (HLB10.0), PEG (10) isostearate (HLB10.0), PEG (15) isostearate (HLB12.0), PEG (20) isostearate (HLB13.0), PEG (25) isostearate (HLB14.0), PEG (30) isostearate (HLB15.0), PEG (40) isostearate (HLB15.0), PEG (50) isostearate (HLB16.0), PEG (60) isostearate (HLB16.0), and the like.

Lipophilic surfactants are: POE (2) stearyl ether (HLB4.0), self-emulsifying propylene glycol monostearate (HLB4.0), glyceryl myristate (HLB3.5), glyceryl monostearate (HLB4.0), self-emulsifying glyceryl monostearate (HLB4.0), glyceryl monoisostearate (HLB4.0), glyceryl monooleate (HLB2.5), hexaglyceryl tristearate (HLB2.5), decaglyceryl pentastearate (HLB3.5), decaglyceryl pentaisostearate (HLB3.5), decaglyceryl pentaoleate (HLB3.5), monostearyl sorbitan ester (HLB4.7), sorbitan tristearate (HLB2.1), sorbitol monoisostearate (HLB5.0), sorbitan sesquiisostearate (HLB4.5), sorbitan monooleate (HLB4.3), POE (HLB 6) sorbitol ester (HLB3.0), POE (POE 3) castor oil (HLB3.0), PEG (2) (HLB4.0), glycol monostearate (HLB3.5), HLB4.5), Stearic acid PEG (2) (HLB4.5), and the like.

Examples of the humectant include polyethylene glycol, propylene glycol, glycerin, 1, 3-butylene glycol, xylitol, sorbitol, maltitol, chondroitin sulfate, hyaluronic acid, mucin sulfate, carotinoid acid (カロニン acid), atelocollagen (アテロコラ - ゲン), cholesteryl-12-hydroxystearate, sodium lactate, bile acid salts, dl-pyrrolidone carboxylate, short-chain soluble collagen, diglycerin (EO) PO adduct, rosa roxburghii (イザヨイバラ) extract, yarrow (セイヨウノコギリソウ) extract, and sweet clover (メリロ - ト) extract.

Examples of the natural water-soluble polymer include: plant-based polymers (e.g., gum arabic, tragacanth gum, galactan, guar gum, locust bean gum, fennel gum, carrageenan, pectin, agar, quince (クインスシ - ド (マルメロ)), starch (rice, corn, potato, wheat), glycyrrhizic acid); microbial polymers (e.g., xanthan gum, dextran, succinoglucan, pullulan (ブルラン), etc.); animal polymers (e.g., collagen, casein, albumin, gelatin, etc.), and the like.

Examples of the semisynthetic water-soluble polymer include: starch-based polymers (e.g., carboxymethyl starch, methyl hydroxypropyl starch, etc.); cellulose polymers (methyl cellulose, ethyl cellulose, methylhydroxypropyl cellulose, hydroxyethyl cellulose, sodium cellulose sulfate, hydroxypropyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, crystalline cellulose, cellulose powder, etc.); alginic acid polymers (e.g., sodium alginate, propylene glycol alginate, etc.), and the like.

Examples of the water-soluble polymer to be synthesized include: vinyl polymers (e.g., polyvinyl alcohol, polyvinyl methyl ether, polyvinyl pyrrolidone, carboxyvinyl polymer, etc.); polyoxyethylene polymers (e.g., polyoxyethylene polyoxypropylene copolymers of polyethylene glycol 20,000, 40,000, 60,000, etc.); acrylic polymers (e.g., sodium polyacrylate, polyethylacrylate, polyacrylamide, etc.); a polyethyleneimine; cationic polymers, and the like.

Examples of thickeners are: gum arabic, carrageenan, veronica, tragacanth, locust bean gum, quince seed, casein, dextrin, gelatin, sodium pectate, sodium arginine, methyl cellulose, ethyl cellulose, CMC, hydroxyethyl cellulose, hydroxypropyl cellulose, PVA, PVM, PVP, sodium polyacrylate, carboxyvinyl polymer, locust bean gum, guar gum, tamarind gum, dialkyl dimethyl ammonium cellulose sulfate, xanthan gum, magnesium aluminum silicate, bentonite, hectorite, AlMg silicate (propolis (ビ - ガム)), synthetic clays (ラポナイト), silicic anhydride, and the like.

The ultraviolet absorber includes the following compounds.

(1) Benzoic acid-based ultraviolet absorber

Examples thereof include p-aminobenzoic acid (hereinafter abbreviated as PABA), PABA monoglyceride, N-dipropoxypPABA ethyl ester, N-diethoxypPABA ethyl ester, N-dimethylpPABA butyl ester, and N, N-dimethylpPABA ethyl ester.

(2) Anthranilic acid-based ultraviolet absorber

For example, homomenthyl N-acetylanthranilate and the like can be mentioned.

(3) Salicylic acid-based ultraviolet absorber

Examples include: amyl salicylate, menthyl salicylate, homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, p-isopropyl phenyl salicylate, and the like.

(4) Cinnamic acid ultraviolet absorbent

Such as octyl cinnamate, ethyl-4-isopropyl cinnamate, methyl-2, 5-diisopropyl cinnamate, ethyl-2, 4-diisopropyl cinnamate, methyl-2, 4-diisopropyl cinnamate, propyl p-methoxy cinnamate, isopropyl p-methoxy cinnamate, isopentyl p-methoxycinnamate, octyl p-methoxycinnamate (2-ethylhexyl p-methoxycinnamate), diethoxyethyl p-methoxycinnamate, cyclohexyl p-methoxycinnamate, ethyl- α -cyano- β -phenyl cinnamate, 2-ethylhexyl- α -cyano- β -phenyl cinnamate, glycerol mono-2-ethylhexanoyl-di-p-methoxycinnamate, and the like.

(5) Triazine-based ultraviolet absorber

Such as bisresorcinyltriazine.

More specifically, there are bis { [4- (2-ethylhexanoyloxy) -2-hydroxy ] phenyl } -6- (4-methoxyphenyl) 1, 3, 5-triazine, 2, 4, 6-tris {4- (2-ethylhexanoyloxycarbonyl) phenylamino }1, 3, 5-triazine and the like.

(6) Other ultraviolet absorbers

Examples include: 3- (4' -methylbenzylidene) -d, 1-camphane, 3-benzylidene-d, pyridazine derivatives such as 1-adamantane, 2-phenyl-5-methylbenzoxazole, 2 '-hydroxy-5-methylphenylbenzotriazole, 2- (2' -hydroxy-5 '-tert-octylphenyl) benzotriazole, 2- (2' -hydroxy-5 '-methylphenylbenzotriazole, dibenzylazine (ジベンザラジン), diantimonyl methane, 4-methoxy-4' -tert-butyldibenzoylmethane, and 5- (3, 3-dimethyl-2-norbornylene) -3-pentan-2-one.

Examples of the metal ion blocking agent include: 1-hydroxyethane-1, 1-diphosphoric acid, 1-hydroxyethane-1, 1-diphosphoric acid tetrasodium salt, ethylenediaminetetraacetic acid disodium salt, ethylenediaminetetraacetic acid trisodium salt, ethylenediaminetetraacetic acid tetrasodium salt, sodium citrate, sodium polyphosphate, sodium metaphosphate, gluconic acid, phosphoric acid, citric acid, ascorbic acid, succinic acid, ethylenediaminetetraacetic acid, ethylenediaminehydroxyethyltriacetic acid trisodium salt, and the like.

Examples of the lower alcohol include ethanol, propanol, isopropanol, isobutanol, and tert-butanol.

Examples of the polyhydric alcohol include: dihydric alcohols (e.g., ethylene glycol, propylene glycol, 1, 2-butanediol, 1, 3-butanediol, butylene glycol, 2, 3-butanediol, pentylene glycol, 2-butene-1, 4-diol, hexylene glycol, octylene glycol, etc.); trihydric alcohols (e.g., glycerin, trimethylolpropane, etc.); tetrahydric alcohols (e.g., pentaerythritol such as 1, 2, 6-hexanetriol); pentahydric alcohols (e.g., xylitol, etc.); hexahydric alcohols (e.g., sorbitol, mannitol, etc.); polyol polymers (e.g., diethylene glycol, dipropylene glycol, triethylene glycol, polypropylene glycol, tetraethylene glycol, diglycerol, polyethylene glycol, triglycerol, tetraglycerol, polyglycerols, and the like); alkyl ethers of glycols (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-methylhexyl ether, ethylene glycol isoamyl ether, ethylene glycol benzyl ether, ethylene glycol isopropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, etc.); glycol alkyl ethers (e.g., diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol butyl ether, diethylene glycol methyl ethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol isopropyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol butyl ether, etc.); glycol ether esters (e.g., ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, ethylene glycol adipate, ethylene glycol disuccinate, diethylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monophenyl ether acetate, etc.); glycerol monoalkyl ethers (e.g., chimyl alcohol, selachyl alcohol, batyl alcohol, etc.); sugar alcohols (e.g., sorbitol, maltitol, maltotriose, mannitol, sucrose, erythritol, glucose, fructose, amylolytic sugars, maltose, xylose, amylolytic sugar-reducing alcohol, etc.); grard (グリソリツド); tetrahydrofurfuryl alcohol; POE-tetrahydrofurfuryl alcohol; POP-butyl ether; POP POE butyl ether; glyceryl tripropylene oxide ether; POP-glycerol ether; POP-glyceryl ether phosphoric acid; POP POE pentaerythritol ether, polyglycerine, and the like.

Examples of monosaccharides include: three carbon sugars (e.g., D-glyceraldehyde, dihydroxyacetone, etc.); four-carbon sugars (e.g., D-erythrose, D-erythrulose, D-tetrose, erythritol, etc.); pentoses (e.g., L-arabinose, D-xylose, L-lyxose, D-arabinose, D-ribose, D-ribulose, D-xylulose, L-xylulose, etc.); hexoses (e.g., D-glucose, D-talose, D-psicose (ブシコ - ス), D-galactose, D-fructose, L-galactose, L-mannose, D-tagatose); hepta-saccharides (e.g., aldoheptoses, heptoses (ヘプロ - ス), etc.); octa-carbon sugars (e.g., octose (オクツロ - ス)), etc.; deoxy sugars (e.g., 2-deoxy-D-ribose, 6-deoxy-L-galactose, 6-deoxy-L-mannose, etc.); aminosugars (e.g., D-glucosamine, D-galactosamine, sialic acid, aminouronic acid, mucic acid (ムラミン acid), etc.); uronic acids (e.g., D-glucuronic acid, D-mannuronic acid, L-glucaric acid, D-galacturonic acid, L-iduronic acid, etc.) and the like.

Examples of oligosaccharides include: sucrose, umbelliferyl (ウンベリフロ - ス), lactose, plantago (プランテオ - ス), iso-periwinkle saccharide, alpha-trehalose, raffinose, periwinkle saccharide, cymine (ウンビリシン), stachyose verbascose (スタキオ - スベルバスコ - ス), and the like.

Examples of the polysaccharide include: cellulose, quince, chondroitin sulfate, starch, galactan, dermatan sulfate, glycogen, gum arabic, heparan sulfate, hyaluronic acid, tragacanth gum, keratan sulfate (ケラタン sulfuric acid), chondroitin, xanthan gum, mucin sulfate, guar gum, dextran, keratosulfate (ケラト sulfuric acid), locust bean gum, succinoglucan, carolinac acid, and the like.

Examples of the amino acids include: neutral amino acids (e.g., threonine, cysteine, etc.); basic amino acids (e.g., hydroxylysine, etc.), and the like. Examples of the amino acid derivatives include: sodium acyl sarcosinate (sodium lauroyl sarcosinate), acyl glutamate, acyl β -alanine sodium, glutathione, pyrrolidone carboxylic acid, and the like.

Examples of the organic amine include monoethanolamine, diethanolamine, triethanolamine, morpholine, triisopropanolamine, 2-amino-2-methyl-1, 3-propanediol, and 2-amino-2-methyl-1-propanol.

Examples of the polymer emulsion include: acrylic resin emulsion, polyethylacrylate emulsion, acrylic resin liquid, polyalkylacrylate emulsion, polyvinyl acetate resin emulsion, natural rubber latex, etc.

Examples of the pH adjuster include: and buffers such as sodium lactate-lactate, sodium citrate-citrate, and sodium succinate-succinate.

Vitamins are, for example: vitamins A, B1, B2, B6, C, E and derivatives thereof, pantothenic acid and derivatives thereof, biotin, and the like.

Examples of the antioxidant include: tocopherols, dibutylhydroxytoluene, butylhydroxyanisole, gallic acid esters, etc.

Examples of the antioxidant auxiliary include: phosphoric acid, citric acid, ascorbic acid, maleic acid, malonic acid, succinic acid, fumaric acid, cephalin, hexamethylphosphate, phytic acid, ethylenediaminetetraacetic acid, and the like.

Other ingredients that may be incorporated are, for example: preservatives (methyl paraben, ethyl paraben, butyl paraben, phenoxyethanol, and the like); anti-inflammatory agents (e.g., glycyrrhizic acid derivatives, glycyrrhetinic acid derivatives, salicylic acid derivatives, hinokitiol, zinc oxide, allantoin, etc.); whitening agents (e.g., saxifrage (ユキノシタ) extract, arbutin, etc.); various extracts (e.g., phellodendron amurense, coptis chinensis, radix violae, paeonia lactiflora, swertia japonica (センブリ), birch (バ - チ), sage (セ - ジ), loquat, carrot, aloe, mallow (ゼニアオイ), iris (アイリス), grape, coix seed, luffa, lily, crocus sativus, ligusticum wallichii, ginger, hypericum erectum (オトギリソウ), formononetin (オノニス), garlic, capsicum, dried orange peel, angelica, seaweed, etc.), activators (e.g., royal jelly, photosensitizer, cholesterol derivative, etc.); blood flow promoters (e.g., benzyl nicotinate, β -butoxyethyl nicotinate, capsaicin (カプサイシン), zingerone, cantharides tincture (カンタリスチンキ), ichthammol, tannic acid, α -borneol, tocopherol nicotinate, phytate, cyclamate (シクランデレ - ト), cinnarizine (シンナリジン), tolazoline (トラゾリン), acetylcholine, verapamil (ベラパミル), cepharanthine (セフアランチン), γ -oryzanol (オリザノ - ル), etc.); antilipolytic agents (e.g., sulfur, dithioanthracene (チアント - ル), etc.); anti-inflammatory agents (e.g., tranexamic acid (トラネキサム acid), thiotaurine, hypotaurine (ヒポタウリン), etc.).

The skin cosmetic of the present invention may be in any form, and is preferably in the form of a skin cosmetic such as a lotion, an emulsion, a cream, or a pack.

Examples

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Unless otherwise specified, the blending amount in examples is mass% (mass percentage).

First, a synthesis example of the microgel used in the present invention will be described. The microgel obtained in the synthesis example is a thickener used in the present invention.

Synthesis example 1

40g of dimethylacrylamide (prepared by Xingan) and 9g of 2-acrylamido-2-methylpropanesulfonic acid (prepared by Sigma) were dissolved in 250g of ion-exchanged water and adjusted to pH 7.0 with sodium hydroxide. Into a 1000ml three-necked flask equipped with a reflux unit were charged 250g of N-hexane, 8.2g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 16.4g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was carried out₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 2

35g of dimethylacrylamide (prepared by Xingan) and 17.5g of 2-acrylamido-2-methylpropanesulfonic acid (prepared by Sigma) were dissolved in 260g of ion-exchanged water and adjusted to pH 7.0 with sodium hydroxide. A1000 ml three-necked flask equipped with a reflux unit was charged with 260g of n-hexane and 8.7g of polyoxyEthylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 17.6g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション) were mixed and dissolved, and N was performed₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 3

30g of dimethylacrylamide (prepared by Xingan) and 26.7g of 2-acrylamido-2-methylpropanesulfonic acid (prepared by Sigma) were dissolved in 280g of ion-exchanged water and adjusted to pH 7.0 with sodium hydroxide. Into a 1000ml three-necked flask equipped with a reflux unit were charged 280g of N-hexane, 9.4g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 19g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was carried out₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 4

35g of dimethylacrylamide (prepared by Xingan) and 17.5g of 2-acrylamido-2-methylpropanesulfonic acid (prepared by Sigma) and 7mg of methylenebisacrylamide were dissolved in 260g of ion-exchanged water and adjusted to pH 7.0 with sodium hydroxide. A1000 ml three-necked flask equipped with a reflux unit was charged with 260g of N-hexane, 8.7g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 17.6g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was added thereto to carry out N dissolution₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 5

35g of dimethylacrylamide (prepared by Xingan) and 17.5g of 2-acrylamido-2-methylpropanesulfonic acid (prepared by Sigma) and 70mg of methylenebisacrylamide were dissolved in 260g of ion-exchanged water and adjusted to pH 7.0 with sodium hydroxide. A1000 ml three-necked flask equipped with a reflux unit was charged with 260g of N-hexane, 8.7g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 17.6g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was added thereto to carry out N dissolution₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is complete, the microgel suspension is addedThe microgel was precipitated with acetone, followed by three washes with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 6

35g of dimethylacrylamide (made by Xinjiang) and 17.5g of 17.5g N, N-dimethylaminopropylacrylamide methyl chloride (made by Xinjiang) were dissolved in 260g of ion-exchanged water. A1000 ml three-necked flask equipped with a reflux unit was charged with 260g of N-hexane, 8.7g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 17.6g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was added thereto to carry out N dissolution₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 ℃, the system is confirmed to be in a semitransparent microemulsion state, and then 2g of ammonium persulfate is added into the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

Synthesis example 7

35g of dimethylacrylamide (made by Xingan), 17.5g N, N-dimethylaminopropylacrylamide methyl chloride (made by Xingan) and 7mg of methylenebisacrylamide were dissolved in 260g of ion-exchanged water. A1000 ml three-necked flask equipped with a reflux unit was charged with 260g of N-hexane, 8.7g of polyoxyethylene (3) oleyl ether (エマレツクス 503, manufactured in Japan エマルション) and 17.6g of polyoxyethylene (6) oleyl ether (エマレツクス 506, manufactured in Japan エマルション), mixed and dissolved, and N was added thereto to carry out N dissolution₂And (4) replacement. To the three-necked flask was added an aqueous monomer solution in N₂Heating to 65-70 ℃ in an oil bath under stirring. When the system temperature reaches 65-70 DEG CAfter confirming that the system was in a translucent microemulsion state at a temperature of C, 2g of ammonium persulfate was added to the polymerization system to initiate polymerization. The polymer system is stirred for 3 hours at 65-70 ℃ and kept to generate microgel. After the polymerization is completed, acetone is added to the microgel suspension to precipitate the microgel, which is then washed three times with acetone to remove residual monomers and surfactants. And filtering the precipitate, and drying under reduced pressure to obtain a white powdery microgel dried product.

The skin cosmetic of the present invention comprises: oil-in-water emulsion products such as emulsion foundations and sunscreen lotions, and oil-in-water cream products such as skin creams. These preparations can be prepared by blending the above essential components with the components usually blended in skin cosmetics according to a conventional method. The details are as follows.

Examples 1 to 10 and comparative examples 1 to 10

An oil-in-water type skin cream was prepared according to the formulation shown in table 1 by a conventional method. The obtained skin cream (sample) was evaluated for stability and usability (spreadability, tenderness, penetration, and adhesion on the skin) according to the following tests.

"stability test"

The sample was left at 50 ℃ for one month and then visually observed for appearance. The judgment was made by the following evaluation criteria.

(evaluation criteria)

O: completely without separation

And (delta): hardly separated from each other

X: producing a separation

"evaluation (1): affinity for skin "

Practical application tests were carried out by 10 panelists for the affinity to the skin in the test. The evaluation criteria are as follows.

Very good: the 8 or more panelists considered that they had affinity with the skin during use.

O: 6 or more but less than 8 panelists considered that the skin had affinity in use.

And (delta): 3 or more but less than 6 panelists considered that the skin had affinity in use.

X: less than 3 panelists considered that the skin had affinity during use.

"evaluation (2): tender feeling "

Practical application tests were conducted by 10 professional evaluators for the tenderness in use. The evaluation criteria are as follows.

Very good: 8 or more professional evaluators considered to have delicate feeling in use.

O: 6 or more but less than 8 professional evaluators considered a delicate feeling in use.

And (delta): 3 or more but less than 6 professional evaluators considered a delicate feeling in use.

X: less than 3 professional evaluators considered a tenderness sensation in use.

"evaluation (3): feeling of penetration into the skin "

Practical application tests were carried out by 10 professional evaluators for the sensation of penetration of the skin in use. The evaluation criteria are as follows.

Very good: 8 or more panelists considered to have a feeling of penetration into the skin in use.

O: 6 or more but less than 8 panelists considered the skin to have a feeling of penetration in use.

And (delta): 3 or more but less than 6 panelists considered the skin to be permeated in use.

X: less than 3 panelists considered a skin penetration sensation in use.

"evaluation (4): no skin-sticking feeling "

Practical application tests were conducted by 10 panelists for the feeling of adhesion to the skin during and after use. The evaluation criteria are as follows.

Very good: 8 or more professional evaluators considered no sense of adhesion to the skin in use.

O: 6 or more but less than 8 panelists considered no sticky feeling to the skin in use.

And (delta): 3 or more but less than 6 panelists considered no sticky feeling to the skin in use.

X: less than 3 panelists considered no sticky feel to the skin during use.

"(evaluation 5): skin moistening feeling "

The actual application test was carried out by 10 professional evaluators for the feeling of skin moisturization after 1 hour of use. The evaluation criteria are as follows.

Very good: the 8 or more panelists considered that there was a feeling of skin moisturization during and after use.

O: the skin was considered moist during and after use by 6 or more but less than 8 panelists.

And (delta): 3 or more but less than 6 panelists considered that there was a feeling of skin moisturization during and after use.

X: less than 3 panelists considered that there was a feeling of skin moisturization during and after use.

[ Table 1]

(^*1) Trade name: synthalen K.3V Group preparation

(^*2) Trade name: pemulen TR-1. produced by Noveon Inc

(^*3) Trade name: preparation of ARISTOFLEX AVC.CLARIANT

(^*4) Trade name: preparation of SIMULGEL EG

(^*5) Trade name: preparation of Kertrol CG. CP Kelco

(^*6) Trade name: preparation of Natrosol Hydroxyyetylcellulose Hercules Incopored

(^*7) Trade name: SEPIGEL 305.SEPIC preparation

(^*8) Trade name: preparation of NIKKOL MGS-ASEV. sunlight ケミカルズ

(^*9) Trade name: NIKKOL MYS-40V. sunlight ケミカルズ preparation

(^*10) Trade name: NIKKOL SS-30V. sunlight ケミカルズ preparation

(^*11) Trade name: preparation of beta-alanyl-L-histidine Symrise

[ Table 2]

(^*1) Trade name: synthalen K.3V Group preparation

(^*2) Trade name: pemulen TR-1. produced by Noveon Inc

(^*3) Trade name: preparation of ARISTOFLEX AVC.CLARIANT

(^*4) Trade name: preparation of SIMULGEL EG

(^*5) Trade name: preparation of Kertrol CG. CP Kelco

(^*6) Trade name: preparation of Natrosol Hydroxyyetylcellulose Hercules Incopored

(^*7) Trade name: SEPIGEL 305.SEPIC preparation

(^*8) Trade name: preparation of NIKKOL MGS-ASEV. sunlight ケミカルズ

(^*9) Trade name: NIKKOL MYS-40V. sunlight ケミカルズ preparation

(^*10) Trade name: NIKKOL SS-30V. sunlight ケミカルズ preparation

(^*11) Trade name: preparation of beta-alanyl-L-histidine Symrise

As is clear from the results in tables 1 and 2, the skin cosmetic (skin cream) of the present invention is excellent in stability and excellent in skin extensibility, tenderness, skin penetration and moisture.

That is, by blending basic β -alanyl-L-histidine and/or a salt thereof known as a drug effective in the inhibition of skin damage/UV immunity induction, anti-wrinkle, parakeratosis inhibition, and pore contraction, with a specific thickener and an inorganic acid and/or an organic acid, the pH can be adjusted to a pH preferable for a skin cosmetic, and a skin cosmetic with a good feeling of use can be provided.

Other embodiments of the invention are given below

Example 11 skin cream

A. Oil phase

(quality)

(compounding ingredients)

％)

Stearic acid 1.0

Stearyl alcohol 0.5

Behenyl alcohol 0.2

Glyceryl monostearate

(trade name: EMALEX GMS-F, manufactured by Japan エマルジョン Co., Ltd.) 2.0

Vitamin E acetate 0.5

Vitamin A palmitate

Tripropylene glycol dineopentanoate 5.0

Isostearyl pivalate 5.0

Macadamia nut oil 1.0

Tea seed oil 1.0

Fragrance 0.4

Proper amount of phenoxyethanol

B. Aqueous phase

Microgel 0.6 of Synthesis example 1

Glycerol 4.0

1, 2-Pentanediol 3.0

Hyaluronic acid sodium salt 0.1

beta-alanyl-L-histidine 1.0

(trade name: Oripeptide CNS, manufactured by Orient Stars LLC)

Ascorbic acid magnesium phosphate 0.1

Citric acid 0.2

Ethylenediaminetetraacetic acid trisodium 0.05

Balance of purified water

(production method and evaluation)

The oil phase of A and the water phase of B were heated to 70 ℃ respectively and completely dissolved. Adding phase A into phase B, and emulsifying with emulsifying machine. The emulsion was cooled by heat exchange to give a skin cream of pH 6.9. The obtained skin cream has good extensibility on skin, delicate feeling, and penetration feeling and no adhesion feeling to skin.

Example 12 body lotion

A. Oil phase

(quality)

(compounding ingredients)

％)

Cetyl alcohol 3.0

Vaseline 7.0

Isopropyl myristate 8.0

Squalane 10.0

Glyceryl monostearate (self-emulsifying type)

(trade name: NIKKOL MGS-BSEV, 2.2, manufactured by Sun light ケミカルズ

Preparation)

POE (20) sorbitan monostearate 2.8

10.0% of diethylene glycol dineopentanoate

Dipropyleneglycol dineovalerate 10.0

Vitamin E nicotinate 2.0

Fragrance 0.3

0.05% of delta-tocopherol

Phenoxyethanol 0.05

B. Aqueous phase

Microgel 1.0 of Synthesis example 3

1, 3-butanediol 5.0

Glycerol 5.0

beta-alanyl-L-histidine

(trade name: Dragosine 2/060700, manufactured by Symrise) 1.0

Dipropylene glycol 4.0

Pyrrolidone carboxylic acid sodium 1.0

Disodium ethylene diamine tetraacetate 0.01

Citric acid 0.3

Balance of purified water

(production method and evaluation)

A body lotion of pH6.7 was obtained according to example 11. The obtained body lotion has good extensibility on skin, delicate feeling, and penetration feeling to skin, and no adhesion feeling.

Example 13 sunscreen emulsion

A. Oil phase

(quality)

(compounding ingredients)

％)

Behenyl alcohol 0.5

Volatile cyclic silicones 10.0

2-ethylhexyl 2-cyano-3, 3-diphenylacrylate (オクトリレン) 2.0

Tert-butyl methoxybenzoylmethane 2.0

Diethylene glycol dineopentanoate 5.0

Ethylhexyl methoxycinnamate 3.0

Bis-ethylhexyloxyphenol methoxyphenyl triazine 0.5

Proper amount of perfume

B. Aqueous phase

Balance of purified water

Microgel 0.3 of Synthesis example 4

Dipropylene glycol 7.0

Decarboxylated carnosine HCl

1.5

(trade name: Carcinine (2HCl), manufactured by Exsymol)

Sodium N-stearoylmethyl taurate

2.0

(trade name: NIKKOL SMT, manufactured by Sun light ケミカルズ Co., Ltd.)

Lactic acid 0.15

(production method and evaluation)

The oil phase and the water phase are mixed and dissolved separately. The oil phase was thoroughly dispersed with titanium dioxide, heated to the water phase, and emulsified with a homogenizer. The sunscreen lotion obtained at pH7.2 had good spreadability on the skin, a delicate feel, a feeling of penetration into the skin, and no sticky feel in use.

Example 14 emulsion

A. Oil phase

(quality)

(compounding ingredients)

％)

Squalane 5.0

Oleic acid oleyl ester 3.0

Vaseline 2.0

Sorbitan sesquioleate 0.8

POE (20) behenyl ether

1.2

(trade name: NIKKOL BB-20, manufactured by Sun light ケミカルズ Co., Ltd.)

Triglycerol dipivalate 2.0

Isodecyl dineopentanoate 2.0

Octyldodecyl neopentanoate 2.0

Evening primrose oil 0.5

Fragrance 0.2

Phenoxyethanol 0.2

B. Aqueous phase

1, 3-butanediol 4.5

Ethanol 3.0

Microgel 0.3 of Synthesis example 5

beta-alanyl-L-histidine

2.0

(trade name: Dragosine 2/060700, manufactured by Symrise)

Citric acid 0.3

Ethylenediaminetetraacetic acid trisodium 0.05

Balance of purified water

(production method and evaluation)

The oil phase and the water phase are mixed and dissolved separately. The aqueous phase was added to the oil phase, and emulsified with a homogenizer to obtain an emulsion having a pH of 7.1. The obtained emulsion has good extensibility on skin, delicate feeling, penetration feeling to skin, and no adhesion feeling.

Industrial applicability

According to the present invention, basic β -alanyl-L-histidine and/or a salt thereof, which are known as effective drugs for suppressing skin damage/UV-induced immunity, anti-wrinkle, parakeratosis, and pore contraction, are blended with a specific thickener and an inorganic acid and/or an organic acid, whereby the pH can be adjusted to a value preferable as a skin cosmetic, and a skin cosmetic having a good feeling of use can be provided.

Claims (8)

1. A skin cosmetic comprising the following components (A), (B) and (C) and satisfying the condition (D),

(A) beta-alanyl-L-histidine and/or salts thereof;

(B) a thickener containing a microgel obtained by dissolving a water-soluble ethylenically unsaturated monomer in a dispersion phase in a composition comprising an organic solvent or an oil component as a dispersion medium and water as a dispersion phase, and performing radical polymerization in the dispersion phase;

(C) inorganic and/or organic acids;

(D) the skin cosmetic has a pH of 5.0 or more and less than 8.0 at 25 deg.C.

2. The skin cosmetic according to claim 1, wherein the microgel of the above (B) is obtained by: the composition with organic solvent or oil as dispersing medium and water as dispersed phase is prepared through free radical polymerization under the condition of forming single-phase microemulsion or fine W/O emulsion with surfactant.

3. The skin cosmetic according to claim 1, wherein the microgel of the (B) has an apparent viscosity in a 0.5 mass% aqueous dispersion at 25 ℃ at a shear rate of 1.0s^-1The lower value is 10000 mPas or more.

4. The skin cosmetic according to claim 1, wherein the microgel of the above (B) has an apparent viscosity of a 0.5 mass% ethanol dispersion at 25 ℃ at a shear rate of 1.0s^-1The lower value is 5000 mPas or more.

5. The skin cosmetic according to claim 1, wherein the microgel of the above (B) has a dynamic elastic modulus of G' (storage elastic modulus) > G "(loss elastic modulus) at 25 ℃ in a 0.5 mass% aqueous or alcoholic dispersion at a strain of 1% or less and at a frequency of 0.01 to 10 Hz.

6. The skin cosmetic according to any one of claims 1 to 5, wherein the water-soluble ethylenically unsaturated monomer of the above (B) is a dialkylacrylamide represented by the general formula (1) and an ionic acrylamide derivative represented by the general formula (2) or (3):

general formula (1)

[ chemical formula 1]

R₁Represents H or methyl, R₂Or R₃Each independently represents methyl, ethyl, propyl, isopropyl;

general formula (2)

[ chemical formula 2]

R₄Or R₅Each independently represents H or methyl, R₆Represents a linear or branched alkyl group having 1 to 6 carbon atoms, X represents a metal ion, NH₃An amine compound;

general formula (3)

[ chemical formula 3]

R₇Represents H or methyl, R₈Represents H or a linear or branched alkyl group having 1 to 6 carbon atoms, R₉Represents a linear or branched alkyl group having 1 to 6 carbon atoms, R₁₀、R₁₁、R₁₂Represents a methyl group or an ethyl group, and Y represents an anionic counterion.

7. The skin cosmetic according to any one of claims 1 to 6, wherein the amount of the component (A) is 0.1 to 3.0% by mass based on the total amount of the skin cosmetic, the amount of the component (B) is 0.1 to 5.0% by mass based on the total amount of the skin cosmetic, and the amount of the component (C) is 0.01 to 1.0% by mass based on the total amount of the skin cosmetic.

8. The skin cosmetic according to any one of claims 1 to 7, wherein the inorganic acid and/or organic acid of the component (C) is one or two or more selected from phosphoric acid, lactic acid and citric acid.