JP7309456B2 - Oil-in-water emulsified UV protection cosmetic - Google Patents

Description

TECHNICAL FIELD The present invention relates to an oil-in-water emulsified UV protective cosmetic composition.

BACKGROUND ART Conventionally, sunscreen cosmetics containing various ultraviolet absorbers have been developed in order to protect the skin from adverse effects of ultraviolet rays.
In particular, Cited Document 1 describes an oil-in-water type UV protection cosmetic containing an organic UV absorber, a silicone oil, and an acrylic acid-based water-soluble polymer.

JP-A-7-89834

In Cited Document 1, since trimethylsiloxysilicate is contained, there is a problem in abrasion resistance.

An object of the present invention is to provide an oil-in-water emulsified UV protective cosmetic that exhibits a high UV protective effect and water resistance in spite of its refreshing feel.

An oil-in-water emulsified UV protective cosmetic containing the following (A) to (D) is provided.
(A) Acrylic acid-based water-soluble polymer (B) Organic ultraviolet absorber (C) One or more spherical powders selected from organic spherical powders and spherical silica, the surface of which is coated with fine zinc oxide particles Composite particles (D) Sorbitan sesquiisostearate

The oil-in-water emulsified UV protective cosmetic composition of the present invention exhibits a high UV protective effect and excellent water resistance in spite of its refreshing use feeling.

A mode for carrying out the present invention will be described below.
Each component will be described below.
The (A) acrylic acid-based water-soluble polymer used in the present invention is not particularly limited as long as it has an acrylic group structure and can be used as a cosmetic. For example, polyacrylic acid and its salts, carbomer, (acrylates/alkyl acrylate (C10-30)) crosspolymer, acrylamide/acrylamido-2-methylpropanesulfonate copolymer, hydroxyethyl acrylate/acryloyldimethyltaurate copolymers, acrylate/acryloyldimethyltaurine copolymers, acrylic acid amide/acrylic acid-2-methylpropanesulfonate copolymers, acryloyldimethyltaurate/vinylpyrrolidone copolymers, and the like. Among these, it is preferable to use an acrylate/acryloyldimethyltaurate copolymer from the viewpoint of stable dispersion of powder, and more preferably a sodium acrylate/sodium acryloyldimethyltaurate copolymer is used. .

The acrylic acid-based water-soluble polymer is preferably added in an amount of 0.01 to 3% by mass based on the total amount of the oil-in-water emulsified UV protective cosmetic. If the content is less than 0.01% by mass, problems may arise in emulsion stability. If the amount is more than 3% by mass, there may be a problem in terms of the feeling of use in terms of the feeling of the film and the feeling of tension.

The (B) organic UV absorber used in the present invention is not particularly limited, and known organic UV absorbers can be used. Organic UV absorbers include, for example, ethylhexyl methoxycinnamate, hexyl diethylaminohydroxybenzoylbenzoate, octyl salicylate, polysilicone-15, t-butylmethoxydibenzoylmethane, oxybenzone, methylenebisbenzotriazolyltetramethylbutylphenol, bis Ethylhexyloxyphenol methoxyphenyltriazine and octocrylene are exemplified, and one or two or more selected from these are used.

Ethylhexyl methoxycinnamate is preferably used from the standpoint of UV absorbability and skin safety. In order to combine the UVA protection function, it is preferable to use one or more selected from ethylhexyl methoxycinnamate, bisethylhexyloxyphenolmethoxyphenyltriazine, octocrylene and hexyl diethylaminohydroxybenzoylbenzoate in combination. .

The amount of the organic UV absorber to be blended is preferably 1% by mass or more, more preferably 2% by mass or more, and may be 5% by mass or more, relative to the total amount of the oil-in-water emulsified UV protective cosmetic. By this, a sufficient sunscreen effect can be obtained.

In addition, the amount of the organic UV absorber to be blended is preferably 20% by mass or less, more preferably 15% by mass or less, relative to the total amount of the oil-in-water emulsified UV protective cosmetic. As a result, the stickiness of the cosmetic can be suppressed, the primary irritation to the skin can be suppressed, and a good feeling of use can be obtained.

(C) used in the present invention is one or two or more kinds of spherical powder selected from organic spherical powder and spherical silica (hereinafter sometimes abbreviated simply as spherical powder). It is a composite particle coated with
Organic spherical powders such as nylon, polymethyl methacrylate, organopolysiloxane elastomer, (acrylates/ethylhexyl acrylate) crosspolymer, acrylates copolymer, acrylates crosspolymer, (dimethicone/vinyl dimethicone) crosspolymer, methylsiloxane Network polymer, crosslinked methylpolysiloxane, urethane resin, polystyrene, acrylonitrile-methacrylic acid copolymer, vinylidene chloride-methacrylic acid copolymer, polyethylene, silk, cellulose and the like. The average particle size of the organic spherical powder and spherical silica is preferably from 2 to 30 μm, more preferably from 3 to 20 μm, in order to form a complex. Here, the average particle size is the volume-based average particle size measured by a laser diffraction/scattering particle size distribution analyzer. Further, the shape of these spherical powders is not limited to true spheres, but means flat, bowl-like, and polygonal shapes, and properties such as solid, hollow, capsule-like, and porous. regardless of

Zinc oxide used in the composite particles of the present invention is not particularly limited as long as it can be incorporated in cosmetics. The shape of zinc oxide is not particularly limited, but the average particle size is preferably 10 to 200 nm, more preferably 15 to 100 nm, and even more preferably 15 to 50 nm, from the viewpoint of UV protection effect.

As zinc oxide, untreated zinc oxide can be used as it is, but it is preferable to use zinc oxide that has been subjected to hydrophobizing treatment. The hydrophobizing agent is not particularly limited, and examples thereof include dimethicone, methylhydrogenpolysiloxane, and metallic soap. Among these hydrophobizing agents, it is preferable to use dimethicone, methylhydrogenpolysiloxane, copolymers thereof, or mixtures thereof. The coating amount of the hydrophobizing agent may be an amount sufficient to hydrophobize zinc oxide. Specifically, the weight ratio of zinc oxide to the hydrophobizing agent is preferably 85:15 to 99:1, more preferably 90:10 to 98:2.

In the composite particles used in the oil-in-water emulsified UV protective cosmetic composition of the present invention, the zinc oxide coating amount is preferably 0.2 parts by mass or more, more preferably 0.3 parts by mass or more, relative to 1 part by mass of the spherical powder. preferable. Also, the coating amount of zinc oxide is preferably 2 parts by mass or less, more preferably 1.5 parts by mass or less with respect to 1 part by mass of the spherical powder. Within this range, both effects of high UV protection effect and refreshing feeling of use can be exhibited.

As a method for coating the spherical powder with zinc oxide, various methods known so far can be used. . From the viewpoint of the ability of the composite particles to solidify sebum, a dry mixed grinding method can be preferably used.

For the composite particles of the present invention, one or more selected from the above spherical powders coated with zinc oxide can be used. Zinc oxide may be untreated zinc oxide, hydrophobized zinc oxide, or a combination thereof. In addition, the cosmetic of the present invention contains composite particles that are a combination of one or more selected from the spherical powders described above and zinc oxide, either singly or in combination of two or more. may be blended together.

By containing the composite particles, the oil-in-water emulsified UV protective cosmetic composition of the present invention can exhibit a high UV protective effect and a refreshing feeling in use.

The amount of the composite particles to be added to the oil-in-water emulsified UV protective cosmetic is preferably 0.5 to 90% by mass based on the total amount of the oil-in-water emulsified UV protective cosmetic. If the amount is less than 0.5% by mass, the sebum-solidifying ability of the composite particles tends to be less effective in the cosmetic. On the other hand, blending more than 90% by mass of composite particles in cosmetics tends to make formulation difficult.

(D) Sorbitan sesquiisostearate used in the present invention is a lipophilic nonionic surfactant. As such sorbitan sesquiisostearate, commercially available ones can be used. ) are exemplified.

The amount of sorbitan sesquiisostearate to be blended can be appropriately determined depending on the organic ultraviolet absorber and other oil agent used in combination. From the viewpoint of imparting stability and water resistance to the oil-in-water emulsified UV protective cosmetic composition, 0.1 to 3% by mass, preferably 0.1 to 2% by mass, based on the total amount of the oil-in-water emulsified UV protective cosmetic composition. .

The oil-in-water emulsified UV protective cosmetic composition of the present invention preferably contains fine metal oxide particles in order to impart UV protective ability. Specific examples of metal oxides include titanium oxide, zinc oxide, cerium oxide, and zirconium oxide. From the viewpoint of ease of blending into oil-in-water emulsified UV protective cosmetics, it is preferable to use one or two selected from fine particle zinc oxide and fine particle titanium oxide, and more preferably fine particle zinc oxide. .

It is preferable to use such a fine particle metal oxide whose surface has been subjected to a hydrophobic treatment. As the hydrophobizing treatment agent, those used in ordinary cosmetics may be used, and examples thereof include fluorine compounds, silicone compounds, organic titanate compounds, metallic soaps, hydrocarbons, higher fatty acids, higher alcohols, ester oils, and waxes. , waxes, surfactants, etc., and a composite treatment using a combination of these may be performed. Among these, hydrophobizing agents selected from higher fatty acids, (dimethicone/methicone) copolymers, trialkoxysilanes, alkyl titanates, and dimethicone are preferred. The surface treatment amount of the hydrophobizing treatment is preferably 0.1 to 10 parts by mass, more preferably 1 to 5 parts by mass, per 1 part by mass of the fine metal oxide particles.

In addition to the above components, the oil-in-water emulsified UV protective cosmetic of the present invention can contain optional components used in ordinary cosmetics and quasi-drugs to the extent that the effects of the present invention are not impaired. . Specific examples include oils, surfactants, thickeners, preservatives, perfumes, moisturizing agents, antioxidants, anti-inflammatory agents, antibacterial agents, whitening agents and the like.

The oil-in-water emulsified UV protective cosmetic composition of the present invention can be prepared by a conventional method.

The oil-in-water emulsified UV protective cosmetic composition of the present invention can be used, for example, in the form of lotions, emulsions and ointments.

EXAMPLES The present invention will be specifically described below with reference to examples, but the scope of the present invention is not limited by these examples.

[SPF evaluation]
For the SPF effect, the SPF value in-vitro was measured using an SPF analyzer (manufactured by UV-2000S Labsphere). The measurement conditions were as follows: After uniformly applying the sample shown in Table 2 to a surgical tape (manufactured by M3) at a rate of 1 mg/cm ² , the SPF value in the range of 290 to 400 nm was measured using the measuring instrument described above. , calculated the average value of 5 points x 3 times, and judged according to the following criteria.
<Judgment Criteria>
(SPF value): (judgment)
30 or more: ○
Less than 30: ×

[Usage evaluation]
Three sensory evaluators specializing in make-up consulted to evaluate lightness and water resistance at the time of application.
◯: High water resistance and light usability.
Δ: The water resistance is slightly poor, and the feeling of use is a little heavy.
x: Poor water resistance and heavy usability.

As shown in Table 1, it was shown that Example 1 of the present invention is an oil-in-water emulsion with a high SPF, excellent in water resistance, and light in use. On the other hand, Comparative Example 1, which was blended without fine zinc oxide coating, had a low SPF and a slightly heavy feel during use. Comparative Example 2, in which sorbitan sesquiisostearate with an HLB value of 8 was replaced with sorbitan isostearate with an HLB value of 9, was inferior in water resistance.

Claims (1)

An oil-in-water emulsified UV protective cosmetic containing the following (A) to (D).
(A) Sodium acrylate/sodium acryloyldimethyl taurate copolymer
(B) one or more selected from ethylhexyl methoxycinnamate, bisethylhexyloxyphenolmethoxyphenyltriazine, octocrylene and hexyl diethylaminohydroxybenzoylbenzoate
(C) 5% Dimethicone Treated Zinc Oxide Coated Methyl Methacrylate Crosspolymer
(D) Sorbitan sesquiisostearate