JP2022149617A - Water-in-oil type cosmetic - Google Patents

Abstract

To provide a water-in-oil type cosmetic which contains a highly-concentrated niacinamide and a UVA absorber, suppresses precipitation of niacinamide and has excellent temporal stability and moisture-retaining feeling.SOLUTION: There is provided a water-in-oil type cosmetic which comprises niacinamide having a content of 3 mass% or more based on the total mass of the water-in-oil type cosmetic, an ultraviolet absorber which absorbs ultraviolet light in the UV-A region, a water-soluble moisturizer having a content of 3 mass% or more based on the total mass of the water-in-oil type cosmetic and an IOB value of 2.4 or more, a silicone-based surfactant, an oil agent containing wax and water having a content of 20 mass% or more based on the total mass of the water-in-oil type cosmetic.SELECTED DRAWING: None

Description

The present disclosure relates to water-in-oil type cosmetics.

Niacinamide (also known as nicotinamide) is one of the B vitamins, which are water-soluble vitamins, and is known to have a wide range of revitalizing effects on the skin, such as promoting blood circulation, anti-inflammatory, whitening, and anti-wrinkle. (See Patent Document 1, for example). Techniques have been proposed for incorporating niacinamide into oily compositions applied to pharmaceuticals, quasi-drugs, or cosmetics.

In Patent Document 1, (A) 3% by mass or more of nicotinic acid amide; and (C) one or more selected from the group consisting of clay-based thickeners, dextrin fatty acid esters, inulin fatty acid esters, and amino acid-based oil gelling agents, A water-in-oil emulsion composition containing an oil-soluble thickener is disclosed.
Patent Document 2 discloses an oily external skin preparation or oily cosmetic containing (A) 1 to 10% by mass of nicotinic acid amide, (B) a liquid oil, (C) an oily thickener, and (D) silica. ing.

Ultraviolet rays are known to cause deterioration of the skin, and various compositions or cosmetics containing ultraviolet absorbers have been proposed as one means of protecting the skin from ultraviolet rays.

In Patent Document 3, a water-in-oil solid cosmetic solidified by wax contains a continuous phase oil that contains an organically modified silicone and forms a continuous oil phase, a wax that is compatible with the continuous phase oil, and an ultraviolet absorber. and an aqueous phase, wherein oil phase droplets containing an ultraviolet absorber and aqueous phase droplets are separately dispersed in a continuous phase oil in which wax is dissolved. Cosmetics are disclosed.
Patent Document 4 discloses (a) an effective amount of a UV inhibitor, (b) a non-thickening oil-absorbing powder having a mineral oil absorption capacity of from about 0.1% to about 70% of at least about 40 ml/100 g, ( c) at least about 10% water by weight of the total composition, and (d) an oil phase comprising: (i) at least about 50% by weight of the oil phase of a volatile silicone oil, and (ii) about 0.1% by weight to less than the oil absorption capacity of the non-thickening oil-absorbing powder.

WO2020/138420 JP 2019-131538 A WO2019/013329 Japanese Patent Publication No. 2004-521959

Both the wide-ranging effect of niacinamide on the skin (e.g., wrinkle-suppressing effect) and the protective effect against ultraviolet rays in the UV-A region (wavelength of 320 nm or more and 400 nm or less), which are said to reach the dermis and damage the skin. As a means of obtaining the above, niacinamide and an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region (hereinafter also referred to as "UVA absorber") may be blended in a water-in-oil cosmetic. In addition, cosmetics may contain a humectant in order to enhance the moisturizing effect.

However, when a water-in-oil type cosmetic containing niacinamide contains a water-soluble moisturizing agent, the niacinamide contained in the aqueous phase (internal phase) may crystallize and precipitate.
Furthermore, in water-in-oil type cosmetics, the UVA absorber needs to be contained in the oil phase (external phase), and the UVA absorber has many components with high solubility and crystallinity. In order to obtain it, it is necessary that the amount of the oil phase is such that the crystallization of the UVA absorber can be suppressed. However, increasing the amount of oil phase relatively decreases the amount of water phase, which can limit the inclusion of high concentrations of niacinamide.
In order to contain a high concentration of niacinamide and suppress precipitation, it is possible to increase the amount of the water phase in the water-in-oil type cosmetic, but the increase in the amount of the water phase relatively decreases the amount of the oil phase, and over time The stability of the oil phase may be impaired when the

The present disclosure has been made in view of the circumstances described above.
The problem to be solved by one embodiment of the present disclosure is that it contains a high concentration of niacinamide and an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region, suppresses the precipitation of niacinamide, and provides stability over time and moisturizing. To provide a water-in-oil type cosmetic excellent in feeling.
Here, in the present disclosure, containing niacinamide at a “high concentration” means containing niacinamide “at least 3% by mass relative to the total mass of the water-in-oil type cosmetic”.

The present disclosure includes the following aspects.
[1] Niacinamide having a content of 3% by mass or more relative to the total mass of the water-in-oil cosmetic, an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region, and the total mass of the water-in-oil cosmetic The content of water-soluble moisturizing agents having a content of 3% by mass or more and an IOB value of 2.4 or more, a silicone-based surfactant, an oil agent containing wax, and a water-in-oil type cosmetic composition with respect to the total mass A water-in-oil type cosmetic containing water having a content of 20% by mass or more.
[2] Does not contain a water-soluble moisturizing agent with an IOB value of 2.1 or less, or contains a water-soluble moisturizing agent with an IOB value of 2.1 or less at 3% by mass based on the total mass of the water-in-oil cosmetic. The water-in-oil type cosmetic according to [1], containing less than
[3] The oil according to [1] or [2], wherein the content of the ultraviolet absorber that absorbs ultraviolet rays in the UV-A region is 2% by mass or more relative to the total weight of the water-in-oil type cosmetic. Middle water type cosmetics.
[[4] The ultraviolet absorber that absorbs ultraviolet rays in the UV-A region is diethylaminohydroxybenzoyl hexyl benzoate, bisethylhexyloxyphenol methoxyphenyl triazine, and diethylamino hydroxybenzoyl hexyl benzoate, bisethylhexyloxyphenol methoxyphenyl triazine, And the water-in-oil type cosmetic according to any one of [1] to [3], which is at least one selected from the group consisting of t-butylmethoxydibenzoylmethane.
[5] The water-soluble moisturizing agent having an IOB value of 2.4 or more contains at least one selected from glycerin and 1,3-butylene glycol, according to any one of [1] to [4]. Water-in-oil cosmetic.
[6] The water-in-oil according to any one of [1] to [5], wherein the content of the silicone surfactant is 1% by mass or more with respect to the total mass of the water-in-oil cosmetic. mold cosmetics.
[7] The water-in-oil cosmetic of any one of [1] to [6], wherein the silicone-based surfactant comprises a polyether-modified silicone surfactant with a branched silicone chain.
[8] The water-in-oil cosmetic according to any one of [1] to [7], wherein the UV absorber contains a UVB absorber.
[9] Any one of [1] to [8], wherein the total content of UV absorbers contained in the water-in-oil cosmetic is 8% by mass or more relative to the total mass of the water-in-oil cosmetic. 1. The water-in-oil type cosmetic according to 1.
[10] The water-in-oil cosmetic according to any one of [1] to [9], wherein the wax content is 3% by mass or more relative to the total mass of the water-in-oil cosmetic.
[11] The water-in-oil type cosmetic according to any one of [1] to [10], which is a solid cosmetic.

According to one embodiment of the present disclosure, an oil that contains a high concentration of niacinamide and an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region, suppresses precipitation of niacinamide, and has excellent stability over time and moisturizing feeling. A medium water type cosmetic is provided.

An example of an embodiment of the water-in-oil cosmetic of the present disclosure (hereinafter sometimes simply referred to as “cosmetics”) will be described below. However, the water-in-oil type cosmetic of the present disclosure is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the present disclosure.

In the present disclosure, a numerical range indicated using "to" means a range including the numerical values before and after "to" as the minimum and maximum values, respectively.
In the present disclosure, in the numerical ranges described in stages, the upper limit or lower limit described in a certain numerical range may be replaced with the upper limit or lower limit of another numerical range described in stages. Also, in the numerical ranges described in the present disclosure, the upper or lower limits of a certain numerical range may be replaced with the values shown in the examples.
In the present disclosure, a combination of two or more preferred aspects is a more preferred aspect.
In the present disclosure, the amount of each component in the cosmetic is the total amount of the multiple substances present in the cosmetic unless otherwise specified when multiple substances corresponding to each component are present in the cosmetic. means.
In the present disclosure, the "oil phase" means the continuous phase of the water-in-oil type cosmetic. In the present disclosure, the oil phase composition includes a liquid medium that constitutes the continuous phase and components dispersed or dissolved in the liquid medium.
In the present disclosure, the "aqueous phase" means the dispersed phase of the water-in-oil type cosmetic. In the present disclosure, the aqueous phase composition includes a liquid medium that constitutes the dispersed phase and components dispersed or dissolved in the liquid medium.

In this disclosure, "PEG" stands for polyethylene glycol and "PPG" stands for polypropylene glycol.

In the present disclosure, "stability over time" means that the oil phase is stable without causing separation or the like when the water-in-oil type cosmetic is aged. Temporal stability should be maintained at least during the storage period set for the water-in-oil type cosmetic.
In the present disclosure, the term “moisturizing feeling” means a feeling of sustained moisture on the skin after the water-in-oil type cosmetic has been applied.
In the present disclosure, the term “freshness” means the feeling of the presence of moisture on the skin immediately after application of the water-in-oil type cosmetic.

<Water-in-oil cosmetics>
The water-in-oil cosmetic of the present disclosure includes niacinamide having a content of 3% by mass or more relative to the total mass of the water-in-oil cosmetic and a content of 3% by mass relative to the total mass of the water-in-oil cosmetic. A water-soluble moisturizing agent having an IOB value of 2.4 or more, an ultraviolet absorber (UVA absorber) that absorbs ultraviolet rays in the UV-A region, a silicone surfactant, and an oil agent containing wax, A water-in-oil cosmetic containing water having a content of 20% by mass or more with respect to the total mass of the water-in-oil cosmetic.

The water-in-oil type cosmetic of the present disclosure contains a high concentration of niacinamide and a UVA absorber, suppresses precipitation of niacinamide, and is excellent in stability over time and moisturizing feeling. Therefore, by using the water-in-oil type cosmetic of the present disclosure, both various activating effects on the skin exhibited by niacinamide and a protective effect against ultraviolet rays in the UV-A region can be obtained, and excellent moisturizing feeling is also obtained. can feel.
Also, for example, niacinamide is known to act on both the dermis and epidermis to suppress the formation of wrinkles (see Cosmetics and Cosmetic Practice, 2014, 103-112). Therefore, in one embodiment, the water-in-oil type cosmetic of the present disclosure has the effect of suppressing wrinkles in which niacinamide acts on the skin from both the epidermis and the dermis, and reaches the dermis to damage the skin. It is possible to obtain both a protective effect against ultraviolet rays in the UV-A region and a cosmetic having an excellent moisturizing feeling.

The reason why the water-in-oil type cosmetic of the present disclosure exerts such effects is not clear, but the present inventors speculate as follows.

The water-in-oil type cosmetic of the present disclosure contains a water-soluble moisturizer having an IOB value of 2.4 or more at a content of 3% by mass or more with respect to the total weight of the water-in-oil type cosmetic, The polarity of the aqueous phase composition in the water-in-oil type cosmetic is maintained at a level at which the solubility of niacinamide, which is a highly polar water-soluble compound, is maintained, and the content of niacinamide at a high concentration and excellent moisturizing sensation are achieved. is presumed to be compatible with In addition, the water-in-oil type cosmetic of the present disclosure contains water at a content of 20% by mass or more with respect to the total mass of the water-in-oil type cosmetic, which is a water-in-oil type internal phase. It is presumed that this relatively increases the amount of the aqueous phase and contributes to the high concentration of niacinamide and the suppression of precipitation. On the other hand, an increase in the amount of the aqueous phase relatively decreases the amount of the oil phase, but the water-in-oil type cosmetic of the present disclosure contains a silicone surfactant, so that the amount of the oil phase is relatively small. Since the stability of the oil phase is maintained even in the case, it is presumed that the stability over time is also excellent.
It should be noted that the above conjecture is not intended to restrictively interpret the water-in-oil type cosmetic of the present disclosure, but is explained as an example.

On the other hand, Patent Documents 1 to 4 do not focus on suppression of precipitation of niacinamide, stability over time, and moisturizing feeling.

Hereinafter, each component contained in the water-in-oil type cosmetic of the present disclosure will be described in detail.

[Niacinamide]
The water-in-oil type cosmetic of the present disclosure contains niacinamide (also known as nicotinamide). Niacinamide may be an extract extracted from natural products such as rice bran, or a synthetic product synthesized by a known production method. As niacinamide, commercially available products may be obtained and used. Specifically, nicotinamide listed in the Japanese Pharmacopoeia 17th Edition can be used.

The water-in-oil cosmetic of the present disclosure contains 3% by mass or more of niacinamide with respect to the total mass of the water-in-oil cosmetic. When the content of niacinamide is 3% by mass or more relative to the total mass of the water-in-oil cosmetic, the desired effect (eg, anti-wrinkle effect) obtained by containing niacinamide is enhanced.

The content of niacinamide is 3% by mass or more with respect to the total mass of the water-in-oil cosmetic, from the viewpoint of the effect obtained by containing niacinamide (preferably, the anti-wrinkle effect) and the suppression of precipitation of niacinamide. 3% by mass to 10% by mass is preferable, 4% by mass to 7% by mass is more preferable, and 4% by mass to 6% by mass is even more preferable.

[Ultraviolet absorber: UVA absorber]
The water-in-oil type cosmetic of the present disclosure contains an ultraviolet absorber (UVA absorber) that absorbs ultraviolet rays in the UV-A region.

In the present disclosure, an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region (UVA absorber) means a compound that absorbs ultraviolet rays in the UV-A region (that is, wavelengths of 320 nm or more and 400 nm or less).
In the present disclosure, an ultraviolet absorber that absorbs ultraviolet rays in the UV-B region (hereinafter also referred to as "UVB absorber") refers to an ultraviolet absorber that absorbs ultraviolet rays in the UV-B region (that is, wavelengths of 280 nm or more and less than 320 nm). means a compound.
Both UVA absorbers and UVB absorbers are preferably organic compounds (ie, organic UV absorbers).
In the present disclosure, organic compounds that absorb ultraviolet rays in both the UV-A region and the UV-B region are included in UVA absorbers.

Examples of UVA absorbers include organic UV absorbers that can be used in the field of quasi-drugs or cosmetics and that have a maximum absorption at a wavelength of 320 nm or more and 400 nm or less.

UVA absorbers include, for example, dibenzoylmethane-based UV absorbers, benzoic acid ester-based UV absorbers, triazine-based UV absorbers, benzophenone-based UV absorbers, phenylbenzotriazole-based UV absorbers, anthranil-based UV absorbers, Among imidazoline-based UV absorbers and 4,4-diarylbutadiene-based UV absorbers, organic UV absorbers having a maximum absorption at a wavelength of 320 nm or more and 400 nm or less can be mentioned.

Specific examples of UVA absorbers include dibenzoylmethane-based UV absorbers such as 4-tert-butyl-4′-methoxydibenzoylmethane (alias: t-butylmethoxydibenzoylmethane, alias: avobenzone);
Benzoic acid ester-based ultraviolet absorbers such as 2-[4-(diethylamino)-2-hydroxybenzoyl]benzoic acid hexyl ester (also known as diethylaminohydroxybenzoyl hexylbenzoate);
2-ethylhexyl dimethoxybenzylidenedioxoimidazolidinepropionate, 2,2′-methylenebis[6-(2H-benzotriazol-2yl)-4-(1,1,3,3-tetramethylbutyl)phenol], 2,4-bis-[{4-(2-ethylhexyloxy)-2-hydroxy}-phenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (also known as bisethylhexyloxyphenol methoxyphenyl triazine), 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]-1,3,5-triazine, and other triazine-based UV absorbers;
Benzophenone UV absorbers such as 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid and salts thereof, dihydroxydimethoxybenzophenone, dihydroxybenzophenone, tetrahydroxybenzophenone;
Phenylbenzotriazole UV absorbers such as Drometrizole trisiloxane, methylenebis(benzotriazolyltetramethylbutylphenol);
anthranil-based UV absorbers such as menthyl anthranilate;
imidazoline UV absorbers such as ethylhexyldimethoxybenzylidene dioxoimidazoline propionate; and
4,4-diarylbutadiene-based UV absorbers such as 1,1-dicarboxy(2,2'-dimethylpropyl)-4,4-diphenylbutadiene can be mentioned.

Hexyl diethylaminohydroxybenzoylbenzoate (maximum absorption wavelength: 355 nm), bisethylhexyloxyphenol methoxyphenyltriazine (maximum absorption wavelength: 340 nm), from the viewpoint of good absorption of UV-A waves and easy availability. and at least one selected from the group consisting of t-butylmethoxydibenzoylmethane (maximum absorption wavelength: 355 nm), and at least one selected from hexyl diethylaminohydroxybenzoylbenzoate and bisethylhexyloxyphenol methoxyphenyltriazine Seeds are more preferred.

A synthetic product may be sufficient as a UVA absorber, and a commercial item may be used.
Examples of commercially available products include Uvinal (registered trademark) A Plus Glanular (hexyl diethylaminohydroxybenzoylbenzoate, BASF Japan Ltd.), Chinosorb (registered trademark) S (bisethylhexyloxyphenol methoxyphenyltriazine, BASF Japan Ltd.). ), Parsol Shield (bisethylhexyloxyphenolmethoxyphenyltriazine, manufactured by DSM), Parsol 1789 (t-butylmethoxydibenzoylmethane, manufactured by DSM), HXMT-100ZA (t-butylmethoxydibenzoylmethane-coated titanium oxide, Taica Co., Ltd.) and the like.

The water-in-oil type cosmetic of the present disclosure may contain only one type of UVA absorber, or may contain two or more types.

[Ultraviolet absorber: UVB absorber]
The water-in-oil type cosmetic of the present disclosure preferably contains an ultraviolet absorber (UVB absorber) that absorbs ultraviolet rays in the UV-B region.
The water-in-oil type cosmetic of the present disclosure preferably uses both a UVA absorber and a UVB absorber.

The UVB absorber is an organic ultraviolet absorber that does not have a maximum absorption at a wavelength of 320 nm or more and 400 nm or less and has a maximum absorption at a wavelength of 280 nm or more and less than 320 nm, among ultraviolet absorbers that can be used in the field of quasi-drugs or cosmetics. can be mentioned.

Examples of UVB absorbers include salicylic acid UV absorbers, cinnamic acid UV absorbers, triazine derivative UV absorbers, benzalmalonate UV absorbers, octocrylene UV absorbers, and imidazole sulfonic acid UV absorbers. and phenylbenzimidazole-based UV absorbers.

Specific examples of UVB absorbers include salicylic acid-based UV absorbers such as 2-ethylhexyl salicylate, homomenthyl salicylate, and ethylene glycol salicylate;
Glyceryl mono-2-ethylhexanoate di-para-methoxycinnamate, ethyl para-dihydroxypropylbenzoate, 2-ethylhexyl para-methoxycinnamate (also known as ethylhexyl methoxycinnamate), isopropyl methoxycinnamate, isoamyl methoxycinnamate Cinnamic acid-based UV absorbers such as;
2,4,6-tris(diisobutyl-4′-aminobenzalmalonate)-s-triazine, 2,4,6-tris[4-(2-ethylhexyloxycarbonyl)anilino]1,3,5-triazine (alias: ethylhexyl triazone), 4,4′-[2-[4-(butylcarbamoyl)anilino]-1,3,5-triazine-4,6-diylbis(imino)]bis(2-ethylhexyl benzoate) ) (alias: diethylhexylbutamide triazone) and other triazine-based UV absorbers;
benzalmalonate-based UV absorbers such as dimethicodiethylbenzalmalonate and polyorganosiloxane having benzalmalonate functional groups;
Octocrylene-based UV absorbers such as 2-cyano-3,3-diphenylprop-2-enoic acid 2-ethylhexyl ester (alias: octocrylene);
imidazole sulfonic acid derivatives such as 2-phenylbenzimidazole-5-sulfonic acid and disodium phenyldibenzimidazole tetrasulfonate; UV absorbers;
PABA derivatives such as para-aminobenzoic acid (hereinafter abbreviated as "PABA"), ethyl PABA, ethyl-dihydroxypropyl PABA, ethylhexyl-dimethyl PABA, glyceryl PABA;
benzylidene camphor-based ultraviolet absorbers such as 3-benzylidene camphor, 4-methylbenzylidene camphor, benzylidene camphor sulfonic acid, benzalkonium methosulfate camphor, terephthalylidene dicamphor sulfonic acid, polyacrylamidemethylbenzylidene camphor; and
Phenylbenzimidazole-based UV absorbers such as disodium phenyldibenzimidazole tetrasulfonate can be mentioned.

From the viewpoint of solubility, 2-ethylhexyl paramethoxycinnamate, ethylhexyltriazone, or octocrylene is preferable as the UVB absorber.

[Ultraviolet absorber: content]
The content of the UVA absorber in the water-in-oil type cosmetic of the present disclosure may be determined according to the type of UVA absorber and the ability to absorb ultraviolet rays.

The content of the UVA absorber is preferably 1% by mass or more, more preferably 2% by mass or more, and 2.5% by mass or more, relative to the total mass of the water-in-oil cosmetic. is more preferred.

The upper limit of the content of the UVA absorber may be determined according to the upper limit of the content in cosmetics determined for each compound.

In one embodiment, the content of the UVA absorber is preferably 1% by mass to 10% by mass, preferably 2% by mass, with respect to the total mass of the water-in-oil type cosmetic from the viewpoint of UV absorption ability. It is more preferably 7% by mass, and even more preferably 2.5% by mass to 5% by mass.

From the viewpoint of obtaining an ultraviolet shielding effect, the water-in-oil cosmetic of the present disclosure is the total content of UV absorbers contained in the water-in-oil cosmetic (that is, the total content of UVA absorbers and UVB absorbers ) is preferably 5% by mass or more, preferably 5% by mass to 12% by mass, more preferably 6% by mass to 11% by mass, based on the total mass of the water-in-oil type cosmetic. Preferably, it is more preferably 7% by mass to 10% by mass.

[Water-soluble moisturizing agent having an IOB value of 2.4 or more]
In the water-in-oil type cosmetics of the present disclosure, a water-soluble moisturizing agent having an IOB value of 2.4 or more (hereinafter referred to as "specific water-soluble moisturizing agent") is added to the total weight of the water-in-oil type cosmetic. It is contained at a content rate of 3% by mass or more. By containing 3% by mass or more of the specific water-soluble moisturizing agent relative to the total mass of the water-in-oil cosmetic, the polarity of the aqueous phase in the water-in-oil cosmetic is increased, and precipitation of niacinamide is suppressed. Moreover, the water-in-oil type cosmetic can have a moisturizing feeling.

In the present disclosure, a "water-soluble moisturizer" may be liquid or solid. A solid water-soluble humectant means a compound that has a solubility of 1 g or more in 100 g of water having a pH of 7.0 at a liquid temperature of 25° C. and functions as a humectant. A liquid water-soluble moisturizing agent means a compound that is mixed with water having a pH of 7.0 in a 1:1 (mass ratio) state at a liquid temperature of 25°C and functions as a moisturizing agent.

The IOB value of the specific water-soluble moisturizing agent is 2.4 or more, preferably 2.4 or more and 6.0 or less, and 2.5 or more and 5.5, from the viewpoint of niacinamide precipitation suppression and moisturizing feeling. The following are more preferable.

The IOB (Inorganic Organic Balance) value is a value representing the ratio of the inorganic value to the organic value.
The IOB value is a value that represents the ratio of the inorganic value (IV: Inorganic Value) to the organic value (OV: Organic Value), which is obtained based on an organic conceptual diagram, and is an index that indicates the degree of polarity of an organic compound. Well known.
The IOB value is represented by the following formula (I). A higher IOB value indicates a higher polarity. The IOB value is explained in detail in "Organic Conceptual Diagram" (Yoshio Koda, Sankyo Publishing, 1984). Specifically, the IOB value is described in "Prediction of Organic Compounds and Organic Conceptual Diagram", Fujita (Kagaku no Ryoryo 11-10), 1957, p. 719-p. 725, "Emulsion formulation design based on organic conceptual diagram", Nippon Emulsion Co., Ltd., Yaguchi, 1985, p. 98].
IOB value = Inorganic value (IV)/Organic value (OV) (I)

In the present disclosure, reference values for the organic value (OV) and inorganic value (IV) used to calculate the IOB value are shown below.
Intramolecular carbon (OV: 20, IV: 0)
Carbon-carbon double bond (OV: 0, IV: 2)
Carbon-carbon triple bond (OV: 0, IV: 3)
Carbon chain branching (OV: -10, IV: 0)
COO (OV: 0, IV: 60)
-OH (OV: 0, IV: 100)
-O- (OV: 0, IV: 20)

The IOB value of the water-soluble moisturizing agent contained in the water-in-oil type cosmetic of the present disclosure can be calculated by identifying the structure of the water-soluble moisturizing agent contained in the water-in-oil type cosmetic and following the above procedure.

The specific water-soluble moisturizing agent may be contained singly or in combination of two or more in the water-in-oil type cosmetic. When the water-in-oil cosmetic contains two or more specific water-soluble moisturizing agents, the IOB value of the water-soluble moisturizing agents in the present disclosure means the IOB value exhibited by each of the specific water-soluble moisturizing agents.

As the specific water-soluble moisturizing agent, a water-soluble moisturizing agent having an IOB value of 2.4 or more may be selected from water-soluble moisturizing agents that can be used in the fields of pharmaceuticals, quasi-drugs, and cosmetics.

Specific water-soluble moisturizing agents include, for example, glycerin (IOB value: 5.0), diglycerin (IOB value: 3.5), and 1,3-butylene glycol (IOB value: 2.5). From the viewpoint of feeling, glycerin and 1,3-butylene glycol are preferred.

The content of the specific water-soluble moisturizing agent is 3% by mass or more, preferably 3% to 15% by mass, based on the total mass of the water-in-oil cosmetic, from the viewpoint of good moisturizing feeling and stickiness control. , 4% by mass to 12% by mass, more preferably 5% by mass to 10% by mass.

The content ratio of niacinamide and the specific water-soluble moisturizing agent (niacinamide: specific water-soluble moisturizing agent) is preferably 10:2 to 10:50 on a mass basis from the viewpoint of niacinamide precipitation suppression and moisturizing feeling. , 10:4 to 10:30 are more preferred.

[Water-soluble moisturizing agent having an IOB value of 2.1 or less]
From the viewpoint of the solubility of niacinamide, the water-in-oil cosmetic of the present disclosure does not contain a water-soluble moisturizer with an IOB value of 2.1 or less, or a water-soluble moisturizer with an IOB value of 2.1 or less. It is preferable to contain the agent in an amount of less than 3% by mass based on the total mass of the water-in-oil type cosmetic.
When a water-soluble moisturizing agent having an IOB value of 2.1 or less is contained, it is preferably 2.5% by mass or less, preferably 2% by mass or less, relative to the total mass of the water-in-oil cosmetic. more preferred.
More preferably, the water-in-oil type cosmetic of the present disclosure does not contain a water-soluble moisturizing agent having an IOB value of 2.1 or less.

Whether or not the IOB value of the water-soluble moisturizing agent is 2.1 or less can be calculated by the method described above.

Examples of water-soluble moisturizers having an IOB value of 2.1 or less include pentylene glycol, dipropylene glycol, menthol, and hexylene glycol.

[Silicone Surfactant]
The water-in-oil type cosmetic of the present disclosure contains a silicone surfactant.
The silicone-based surfactant is not particularly limited as long as it is used in the fields of pharmaceuticals, quasi-drugs, or cosmetics.

Examples of silicone-based surfactants include polyether-modified silicone-based surfactants, polyether/alkyl co-modified silicone-based surfactants, polyglycerin-modified silicone-based surfactants, and polyglycerin/alkyl-co-modified silicone-based surfactants. active agents.

Specific examples of silicone surfactants include PEG-10 dimethicone, PEG-3 dimethicone, PEG-12 dimethicone, PEG/PPG-19/19 dimethicone, polysilicone 13, PEG-9 polydimethylsiloxyethyl dimethicone, and the like. polyether-modified silicone surfactant;
Polyether/alkyl co-modified silicone surfactants such as methylpolysiloxane/cetylmethylpolysiloxane/poly(oxyethylene/oxypropylene) methylpolysiloxane copolymer, lauryl PEG-9 polydimethylsiloxyethyl dimethicone;
Polyglycerin-modified silicone surfactants such as bisbutyl dimethicone polyglyceryl-3, polyglyceryl-3 polydimethylsiloxyethyl dimethicone, polyglyceryl-3 disiloxane dimethicone; and
Examples include polyglycerin/alkyl co-modified silicone surfactants such as lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone.

Among the silicone-based surfactants described above, the water-in-oil type cosmetic of the present disclosure preferably contains a polyether-modified silicone surfactant having a branched silicone chain, from the viewpoint of uniformity of the oil phase. .

A polyether-modified silicone surfactant having a branched silicone chain is a polyether-modified silicone surfactant having a structure in which one or more siloxane bond chains are branched from the siloxane bond chain that constitutes the main chain of the polyether-modified silicone surfactant. means a silicone surfactant.

Polyether-modified silicone-based surfactants with branched silicone chains include, for example, PEG-10 dimethicone, PEG-3 dimethicone, PEG-12 dimethicone, PEG/PPG-19/19 dimethicone, polysilicone 13, PEG- 9 Polydimethylsiloxyethyl dimethicone, methylpolysiloxane/cetylmethylpolysiloxane/poly(oxyethylene/oxypropylene) methylpolysiloxane copolymer, lauryl PEG-9 Polydimethylsiloxyethyl dimethicone, bisbutyl dimethicone polyglyceryl-3, polyglyceryl- 3 polydimethylsiloxyethyl dimethicone, polyglyceryl-3 disiloxane dimethicone, and lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone, with PEG-9 polydimethylsiloxyethyl dimethicone being preferred.

The silicone-based surfactant may be a commercial product or a synthetic product.
Commercially available products include, but are not limited to, KF-6017 (Shin-Etsu Chemical Co., Ltd.), KF-6019 (Shin-Etsu Chemical Co., Ltd.), KF-6015 (Shin-Etsu Chemical Co., Ltd.), SH3772M (Toray Industries, Inc.), Dow Corning Co., Ltd.) SH3775M (Dow Corning Toray Co., Ltd.) BY-11-030 (Dow Corning Toray Co., Ltd.), KF-6004 (Shin-Etsu Chemical Co., Ltd.), KF-6011 ( Shin-Etsu Chemical Co., Ltd.), FZ-2222, FZ-2233, KF-6028 (Shin-Etsu Chemical Co., Ltd.), ABIL EM90 (manufactured by Goldschmidt), KF-6048 (Shin-Etsu Chemical Co., Ltd.) , KF-6038 (Shin-Etsu Chemical Co., Ltd.), KF-6104, KF6106 (Shin-Etsu Chemical Co., Ltd.), KF-6100 (Shin-Etsu Chemical Co., Ltd.), KF-6105 (Shin-Etsu Chemical Co., Ltd.) etc.

The water-in-oil type cosmetic composition may contain one type of silicone surfactant alone, or two or more types thereof.

From the viewpoint of uniformity of the oil phase, the content of the silicone surfactant is preferably 1% by mass or more, and 1.0% to 5% by mass, based on the total mass of the water-in-oil type cosmetic. 0 mass % is more preferable, 1.5 mass % to 4.0 mass % is even more preferable, and 2.0 mass % to 3.0 mass % is particularly preferable.

[Oil agent containing wax]
The water-in-oil type cosmetic of the present disclosure contains an oil agent. Oil agents include waxes.
The oil agent can be contained as a base of the water-in-oil type cosmetic of the present disclosure.
As the oil agent, a component generally used as an oil agent in the field of cosmetics can be used. The oil may be liquid, semi-solid, solid, or a mixture thereof.
The oil agent may be selected from the viewpoint of imparting viscosity or hardness to the cosmetic.
The oil agent may be a commercial product or a synthetic product.
The oil agent is not particularly limited as long as it is an oil agent applicable to cosmetics, except that it contains wax.

(wax)
In the present disclosure, “wax” is one form of an oil, and is a general term for organic substances that are solid at 25° C. and become liquid when heated. The wax in the present disclosure does not include oils that fall under the "oils other than waxes" described later.
As the wax in the present disclosure, an oil used as a wax in the field of cosmetics can be used without particular limitation. The inclusion of wax in the water-in-oil type cosmetic of the present disclosure can contribute to solidification of the cosmetic.

Waxes in the present disclosure include, for example, hydrocarbon waxes such as paraffin wax, ceresin wax, microcrystalline wax, Fischer-Tropsch wax, and polyethylene wax; vaseline; of vegetable or animal waxes.

One type of wax may be contained alone, or two or more types may be contained in the water-in-oil type cosmetic.
The wax content can be, for example, 1% by mass or more, preferably 1% to 8% by mass, and 2% to 6% by mass, based on the total mass of the water-in-oil type cosmetic. % is more preferred. Setting the wax content within the above range is advantageous, for example, when the water-in-oil type cosmetic of the present disclosure is used as a solid cosmetic.

(Oils other than wax)
Oil agents other than waxes include, for example, hydrocarbon oils, ester oils, silicone oils, silicone gels, higher fatty acids, higher alcohols, and oils belonging to natural animal and plant oils other than waxes. .

Hydrocarbon oils include liquid paraffin, isoparaffin, ethylene/propylene copolymer, hydrogenated polyisobutene, squalane and the like.

Ester oils include pentaerythrityl tetraethylhexanoate, cetyl ethylhexanoate, di(phytosteryl/octyldodecyl) lauroyl glutamate, triisostearin, glyceryl stearate, glyceryl diisostearate, triethylhexanoin, dimer dilinoleic acid (phytosteryl/behenyl ), dimer dilinoleic acid (phytosteryl/isostearyl/cetyl/stearyl/behenyl), isopropyl palmitate, macadamia nut fatty acid phytosteryl, tetra(behenate/benzoate/ethylhexanoate) pentaerythrityl, ethylhexyl palmitate, myristyl myristate , tripropylene glycol dipivalate, isotridecyl isononanoate, rosin acid pentaerythrite ester, (behenate/eicosanedioate) glyceryl, (behenate/eicosanedioate) polyglyceryl-10, polysorbate 60, and the like.

Examples of silicone oils include dimethylpolysiloxane (chain polysiloxane such as dimethicone, methylphenylpolysiloxane, decamethyltetrasiloxane, and methylhydrogenpolysiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, , cyclic polysiloxanes such as tetramethyltetrahydrogencyclotetrasiloxane, and caprylyl methicone.

Silicone gel refers to a crosslinked silicone product in which silicone chains forming the main chain skeleton are crosslinked with each other by polyether chains, polyglycerin chains, silicone chains, or the like. Depending on the chain structure used for cross-linking, there are types such as polyether-modified silicone gel, polyglycerin-modified silicone gel, polyether/alkyl co-modified silicone gel, and polyglycerin/alkyl co-modified silicone gel.

Specific examples of silicone gels include (dimethicone/(PEG-10/15) crosspolymer, (PEG-15/lauryl dimethicone) crosspolymer, (PEG-10/lauryl dimethicone) crosspolymer, (PEG-15/lauryl polydimethylsiloxyethyl dimethicone) crosspolymer, (dimethicone/polyglycerin-3) crosspolymer, (lauryl dimethicone/polyglycerin-3) crosspolymer, (polyglyceryl-3/lauryl polydimethylsiloxyethyl dimethicone) crosspolymer, (dimethicone/ vinyl dimethicone) crosspolymer, (dimethicone/phenyl vinyl dimethicone) crosspolymer, (vinyl dimethicone/lauryl dimethicone) crosspolymer, (lauryl polydimethylsiloxyethyl dimethicone/bisvinyl dimethicone) crosspolymer, and the like.

Higher fatty acids include stearic acid, lauric acid, myristic acid, behenic acid, and the like.

Higher alcohols include cetyl alcohol, stearyl alcohol, lauryl alcohol, behenyl alcohol, and the like.

Natural animal and plant oils include jojoba seed oil, avocado oil, almond oil, olive oil, cocoa oil, sesame oil, wheat germ oil, safflower oil, shea butter, turtle oil, camellia oil, persic oil, castor oil, grape oil, and macadamia nut oil. , coconut oil, rosehip oil, soybean oil, egg yolk oil, hydrogenated castor oil, hydrogenated coconut oil, hydrogenated cocoa oil, hydrogenated turtle oil, hydrogenated mink oil, beef oil, mink oil, lanolin (so-called wool fat), etc. mentioned.

Oils other than waxes may be contained singly or in combination of two or more in the water-in-oil type cosmetic.

〔water〕
The water-in-oil cosmetic of the present disclosure contains water at a content of 20% by mass or more relative to the total mass of the water-in-oil cosmetic.
Water is not particularly limited as long as it can be applied to cosmetics.

The content of water is 20% by mass or more, preferably 25% by mass or more, and more preferably 30% by mass or more, from the viewpoint of suppression of precipitation of niacinamide and feeling of use (e.g., freshness). preferable.
The upper limit of the water content is not particularly limited as long as it is a water-in-oil type cosmetic. The water content can be, for example, 70% by mass or less, preferably 50% by mass or less.

The content ratio of niacinamide to water (niacinamide:water) is preferably 1:3 to 1:12, more preferably 1:4 to 1:10, based on mass, from the viewpoint of suppressing precipitation of niacinamide. , 1:5 to 1:9 are more preferred.

[Other ingredients]
The water-in-oil type cosmetic of the present disclosure may contain other ingredients than the ingredients described above.
Other ingredients may be any ingredients that can be blended in cosmetics, such as feel improvers, surfactants other than silicone-based surfactants, water-soluble organic solvents, preservatives (phenoxyethanol, methylparaben, etc.), and pH adjustment. agents, pH buffers, antioxidants, silicone resins such as crosslinked silicone/reticular silicone block copolymers, ultraviolet scattering agents (titanium oxide, zinc oxide, etc.), coloring agents, fragrances, and the like.

[Proportion of oil phase and water phase]
In the water-in-oil type cosmetic, the ratio of the oil phase to the water phase (oil phase: water phase) is preferably 65:35 to 35:65, more preferably 60:40 to 40:60, as a mass ratio. Preferred is 55:45 to 45:55.

[Form of water-in-oil type cosmetic]
The form of the water-in-oil cosmetic of the present disclosure is not particularly limited, and may be either liquid or solid (including semi-solid) at room temperature (25°C).
The water-in-oil type cosmetic of the present disclosure is preferably a solid cosmetic.
The solid cosmetic in the present disclosure has a hardness that allows it to be molded, and is in a form that maintains the molded state when the molded product is left at room temperature (25° C.) without being placed in a container. is preferred.

[Viscosity or hardness of water-in-oil cosmetic]
The viscosity or hardness of the water-in-oil type cosmetic of the present disclosure can be adjusted according to the container.
When the water-in-oil cosmetic has a viscosity measurable form, the viscosity at 25° C. is preferably 5000 mPa·s or more, more preferably 10000 mPa·s or more, and even more preferably 15000 mPa·s or more.
When the water-in-oil type cosmetic has a form in which the viscosity cannot be measured, the indentation hardness of the water-in-oil type cosmetic at 25°C is preferably 10 g or more, more preferably 15 g or more, and still more preferably 20 g or more.
When the indentation hardness cannot be measured because it is too hard, the penetration hardness is measured as the hardness of the water-in-oil type cosmetic of the present disclosure. The penetration hardness at 25° C. of the water-in-oil cosmetic is preferably 30 g to 150 g.

The viscosity can be measured by, for example, using a BL-type viscometer (M4 rotor) and stirring for 60 seconds at a rotor speed of 6 rpm. As the BL type viscometer, for example, VISCOMETER TVB-10 manufactured by Toki Sangyo Co., Ltd. can be preferably used. However, the BL-type viscometer is not limited to this.
The indentation hardness is measured using, for example, a rheometer (manufactured by Rheotec Co., Ltd.), and the indentation hardness (g/cm ² ) is measured under the measurement conditions (adaptor: disk-shaped 20 mmφ, speed: 6 cm/min, depth: 20 mm). can be measured by
Penetration hardness is measured using a rheometer (manufactured by Rheotec Co., Ltd.) to measure penetration hardness (g/cm ² ) under measurement conditions (adaptor: 3φ rod-shaped adapter, speed: 6 cm/min, depth: 15 mm). can be measured by

[Container for water-in-oil cosmetic]
A container for containing the water-in-oil type cosmetic of the present disclosure is not particularly limited.
Examples of containers include stick-type, compact-type, jar-type, tube-type, and pump-type containers.

[Uses of water-in-oil type cosmetics]
Applications of water-in-oil type cosmetics include skin care cosmetics, makeup cosmetics, and hair cosmetics. In certain embodiments, the water-in-oil type cosmetic of the present disclosure is preferably a skin care cosmetic.

[Method for producing water-in-oil cosmetic]
The method for producing the water-in-oil type cosmetic of the present disclosure is not particularly limited, and it can be produced according to a known method for producing a water-in-oil type cosmetic.
For example, an oil phase composition containing a UVA absorber, a silicone surfactant, and a wax-containing oil agent is prepared, and the obtained oil phase composition, niacinamide, and a specific water-soluble moisturizing agent are prepared. A water-in-oil type cosmetic can be produced by mixing and emulsifying an aqueous phase composition containing an agent and water.
Optional components other than those described above can be used in the oil phase composition and the aqueous phase composition, if necessary.

One of the preferred methods for producing the water-in-oil type cosmetic of the present disclosure is
A step of heating and mixing an oil phase component including a UVA absorber, a silicone surfactant, an oil agent containing wax, and other optional ingredients to obtain an oil phase composition;
A step of mixing aqueous phase components including niacinamide, a specific water-soluble moisturizing agent, water, and other optional ingredients to obtain an aqueous phase composition;
A step of mixing and emulsifying the heated oil phase composition and a separately heated aqueous phase composition;
is preferably included.

The heating temperature in each step can be, for example, 80.degree. C. to 90.degree.
As means for emulsifying and mixing, known means may be used, for example, a homomixer can be used.
Conditions for emulsification may be determined by adjusting the shear rate, treatment time, etc. according to the viscosity required for the water-in-oil type cosmetic, the size of emulsified particles (aqueous phase), and the like.
The obtained water-in-oil type cosmetic can be filled in a suitable container in a fluid state and solidified by cooling.

Hereinafter, the water-in-oil type cosmetic composition of the present disclosure will be described more specifically with reference to examples, but the water-in-oil type cosmetic composition of the present disclosure is not limited to the following examples.

[Examples 1 to 13, Comparative Examples 1 to 7]
Each component shown in the oil phase column of Table 1, Table 2 or Table 3 was heated and mixed at 80°C to prepare an oil phase composition.
Each component described in the water phase column of Table 1, Table 2 or Table 3 was mixed to prepare a water phase composition, and the resulting water phase composition was heated to 80°C.
The water phase composition is mixed with the oil phase composition, and while maintaining the temperature at 80 ° C., a homomixer is used at a rotation speed of 3000 rpm (revolutions per minute, hereinafter the same) for 10 minutes to apply shear force and Stirring was performed to obtain an emulsion. The resulting emulsion was filled into a container at 70°C ± 10°C. When unevenness occurs on the top of the filling, a process of melting and flattening with a heating device (such as a dryer) is included. As the container, Examples 1 to 12 used a lipstick container, and Example 13 used a jar container.
As described above, a water-in-oil type cosmetic was obtained.
The water-in-oil type cosmetics obtained in Examples 1 to 12 are all solid cosmetics.
The water-in-oil type cosmetic obtained in Example 13 is a emulsion-like cosmetic (that is, a liquid cosmetic).

Each component used in Examples 1 to 13 and Comparative Examples 1 to 7 and its content (% by mass) are shown in the composition column of Table 1, Table 2 or Table 3. In addition, in Table 1, Table 2 or Table 3, "-" in the composition column indicates that the component is not contained.

[evaluation]
(Measurement of UV shielding ability: Measurement of PA (Protection Grade of UV-A) value (in vitro))
Samples prepared from each water-in-oil type cosmetic thus obtained were measured for PA value by the following measuring method. The PA value was "20 or more" for all samples.
A PA value of "20 or more" means having a practically acceptable level of UV protection.
-Measuring method-
Each obtained water-in-oil cosmetic was weighed and applied to a polymethyl methacrylate (PMMA) plate so as to be 1.3 mg/cm ² to prepare a sample. The PA value was measured for the sample using an SPF analyzer UV-1000S (manufactured by Labsphere).

(Precipitation suppression of niacinamide)
Each obtained water-in-oil type cosmetic was heated to 50° C. on a slide glass, and then slowly cooled to room temperature (25° C.). The water-in-oil type cosmetic after cooling was visually observed under an optical microscope (magnification: 1050) for the presence or absence of niacinamide crystals, and evaluated according to the following criteria. Evaluation level A or B is a practically acceptable level, and A is more preferable. The results are shown in Table 1, Table 2 or Table 3.
-Evaluation criteria-
A; no crystals were generated.
B: A slight amount of crystals was generated.
C: A large amount of crystals were produced.

(Stability over time)
Each obtained water-in-oil type cosmetic was aged at 50° C. for one month.
The water-in-oil type cosmetic before and after aging was visually observed and evaluated according to the following criteria. Evaluation ranks "4" and "3" mean that the water-in-oil type cosmetic has a practically acceptable level of uniformity of the oil phase, and "4" is more preferable. The results are shown in Table 1, Table 2 or Table 3.
-Evaluation criteria-
4: Same as immediately after production, no change.
3: A small amount of oil floated on the side of the solid cosmetic or on the top of the liquid cosmetic, but it was practically acceptable.
2: Practically unacceptable degree of oil floating occurred on the side of the solid cosmetic or on the upper portion of the liquid cosmetic.
1: Oil floating occurred on the entire cosmetic.

(moisturizing feeling)
Five professional evaluators applied each water-in-oil type cosmetic to the face with their fingers, and evaluated the moisturizing feeling (moisturizing feeling) after application according to the following four-level evaluation criteria. Then, A: 4 points, B: 3 points, C: 2 points, C: 1 point, the evaluation scores of 5 people were averaged, and the evaluation rank corresponding to the value rounded to the first decimal place was determined as the moisturizing feeling. This is the evaluation result. The results are shown in Table 1, Table 2 or Table 3. Evaluation ranks of "4" and "3" are practically acceptable levels, and "4" is more preferable.
-Evaluation criteria-
4: A feeling of moisture was felt.
3: A slightly moist feeling was felt.
2: Did not seldom feel moisturizing.
1: Did not feel moist

(freshness)
Five professional evaluators applied each water-in-oil type cosmetic to the face with their fingers, and evaluated the freshness according to the following four-level evaluation criteria. Then, A: 4 points, B: 3 points, C: 2 points, C: 1 point, the evaluation scores of 5 people are averaged, and the evaluation rank corresponding to the value rounded to the first decimal place is determined as the freshness. This is the evaluation result. The results are shown in Table 1, Table 2 or Table 3. Evaluation ranks of "4" and "3" are practically acceptable levels, and "4" is more preferable.
-Evaluation criteria-
4: Freshness was felt.
3: Freshness was felt a little.
2: Freshness was not felt so much.
1: Freshness was not felt.

In Tables 1, 2 and 3, "%" indicates "% by mass".
Details of each component shown in Tables 1, 2 and 3 are as follows.

・ Niacinamide [trade name: niacinamide PC, manufactured by DSM]
・Glycerin [specific water-soluble moisturizing agent, IOB = 5.0]
・DPG: 1,3-butylene glycol [specific water-soluble moisturizing agent, IOB = 2.5]
・Menthol [water-soluble moisturizing agent, IOB=1.7]
・Pentylene glycol (water-soluble moisturizing agent, IOB=2.0)
・Ethylhexylglycerin ・Phenoxyethanol

・Diethylaminohydroxybenzoyl hexyl benzoate [UVA absorber, trade name: Ubinal A Plus GranuLar, BASF Japan Ltd.]
・Bisethylhexyloxyphenol methoxyphenyltriazine [UVA absorber, trade name: Chinosorb S, BASF Japan Ltd.]
・t-butyl methoxydibenzoylmethane [UVA absorber]
・Ethylhexyl palmitate [UVB absorber]
・2-Ethylhexyl p-methoxycinnamate [UVB absorber]

・PEG-9 polydimethylsiloxyethyl dimethicone [silicone surfactant]
・PEG-10 dimethicone [silicone surfactant]
・Candelilla wax [wax (oil agent)]
・Ceresin wax [wax (oil agent)]
・Dimethicone (oil)
・Methylphenyl polysiloxane [oil agent]
・Decamethyltetrasiloxane [oil agent]

・Neopentyl glycol 2-ethylhexanoate ・Polyglyceryl-2 diisostearate
・Crosslinked silicone ・Reticulated silicone block copolymer [silicone resin]

As shown in Table 1, the water-in-oil type cosmetics of Examples 1 to 13 inhibited precipitation of niacinamide, and were excellent in stability over time and moisturizing feeling. Furthermore, the water-in-oil type cosmetics of Examples 1 to 13 were also excellent in freshness.

Comparative Example 1 did not contain a moisturizing agent, and the moisturizing feeling was at a practically unacceptable level.
In Comparative Example 2, the content of the specific water-soluble moisturizing agent was less than 3% by mass with respect to the total mass of the water-in-oil type cosmetic, and the moisturizing feeling was at a practically unacceptable level.
In Comparative Example 3, the content of the specific water-soluble moisturizing agent is less than 3% by mass with respect to the total mass of the water-in-oil cosmetic, and the content of the water-soluble moisturizing agent having an IOB value of 2.1 or less. was 3% by mass or more, and niacinamide precipitated to a level that was practically unacceptable.
In Comparative Example 4, the content of the specific water-soluble moisturizing agent is less than 3% by mass and the IOB value is 2.1 or less relative to the total mass of the water-in-oil type cosmetic. was less than 3% by mass, niacinamide precipitated at a practically unacceptable level, and the moisturizing sensation was at a practically unacceptable level.
In Comparative Example 5, the water content was less than 20% by mass with respect to the total mass of the water-in-oil type cosmetic, and niacinamide precipitated at a practically unacceptable level, and freshness was not obtained. .
Comparative Examples 6 and 7 did not contain a silicone-based surfactant, and their stability over time was at a practically unacceptable level.

[Example 14]
<Preparation of pyridoxine hydrochloride liposome composition>
The following components were stirred for 10 minutes while heating at 60° C. and dissolved to obtain an oil phase composition A.
-Oil phase composition A-
・Hydrogenated soybean phospholipid 55.0g
・Polyoxyethylene phytosterol 11.5g
・Cholesterol 15.0g
・5.0 g of oleic acid
・Anhydrous ethanol 1005.0g
・Ascorbyl tetra-2-hexyldecanoate 5.0g

While heating at 60° C., the following components were stirred for 10 minutes and dissolved to obtain an aqueous phase composition A.
-Aqueous phase composition A-
・Pyridoxine hydrochloride 25.0g
・ Niacinamide 5.0g
・Anhydrous sodium monohydrogen phosphate 2.0g
・ Sodium hydroxide liquid 106.5 g
・ Purified water 3765.0 g

The following ingredients were stirred for 10 minutes while heating at 60° C. and dissolved to obtain an aqueous phase composition B.
- Aqueous phase composition B -
・Methyl paraoxybenzoate 20.0 g
・ Purified water 4980.0 g

The aqueous phase composition A obtained above is stirred with a homomixer (model name: Automixer Model 40, Primix Co., Ltd.) while being kept at 60 ° C. (rotation speed: 1800 rpm), to the aqueous phase composition A. Oil phase composition A was added. Stirring was continued at 1800 rpm for 90 minutes after the addition. After stirring, the aqueous phase composition B was added, and the mixture was uniformly stirred for 5 minutes and cooled to 35°C or lower. After cooling, the mixture was filtered through a 230-mesh filter cloth to obtain a pyridoxine hydrochloride-containing liposome composition.

(Observation of liposomes)
The resulting pyridoxine hydrochloride-containing liposome composition was diluted to 10% by mass with Milli-Q water, and the particle size of the dispersed particles was measured using a particle size analyzer FPAR-1000 (Otsuka Electronics Co., Ltd.). 300 nm. Milli-Q water is ultrapure water obtained by Milli-Q water purifier, which is an ultrapure water purifier manufactured by Merck. In addition, a transmission electron microscope (TEM) image of the resulting liposome-forming composition was observed, and unilamellar liposomes were observed.

The details of each component used in the preparation of the pyridoxine hydrochloride liposome composition are as follows.
・Hydrogenated soybean phospholipid [trade name: COATSOME NC-21, NOF Corporation]
・Polyoxyethylene phytosterol [trade name: NIKKOL BPS-20, Nikko Chemicals Co., Ltd.]
・Cholesterol [Product name: Cholesterol JSQI, Nippon Fine Chemical Co., Ltd.]
・Oleic acid [Product name: Lunaq OV, Kao Corporation]
・Anhydrous ethanol [trade name = Traceable 99 Grade 1, Kanto Kagaku Co., Ltd.]
・Ascorbyl tetra-2-hexyldecanoate [trade name: NIKKOL VC-IP, Nikko Chemicals Co., Ltd.]
・Pyridoxine hydrochloride [trade name: pyridoxine hydrochloride, DSM Corporation]
・Niacinamide [trade name: niacinamide PC, DSM Corporation]
・Anhydrous sodium monohydrogen phosphate [trade name: anhydrous sodium monohydrogen phosphate (Gaigenki), Taihei Kagaku Sangyo Co., Ltd.]
・ Sodium hydroxide solution [Product name: Food additive 4% by mass caustic soda, Takasugi Pharmaceutical Co., Ltd.]
・Methyl paraoxybenzoate [Product name: Mekkinsu M, Ueno Pharmaceutical Co., Ltd.]

<Preparation of water-in-oil type cosmetic>
Example 1 except that 2% by mass of the water (37.0% by mass) contained as the aqueous phase component was replaced with 2% by mass of the pyridoxine hydrochloride-containing liposome composition prepared above. In the same manner as above, a water-in-oil cosmetic of Example 14 shown in Table 4 was prepared.
The content rate "%" of each component shown in Table 4 is "% by mass".

Each water-in-oil type cosmetic of Examples contains a high concentration of niacinamide and a UVA absorber, and provides excellent moisturizing feeling (that is, moisturizing feeling) and freshness during use. An example of a suitable usage pattern includes use during the day (for example, in the morning).
In addition, the water-in-oil type cosmetic of the present disclosure can also be used in combination with other cosmetics. An example of a combination mode includes a combination of a daytime cosmetic that is a water-in-oil type cosmetic of the present disclosure and a nighttime cosmetic (for example, cream) with higher moisturizing properties. Specific examples of such combinations include combinations of each of the water-in-oil type cosmetics of the Examples and the cosmetic (cream) of Reference Example 1 shown below.

[Reference Example 1: Cream]
A cream having the following composition was prepared by a conventional method (total amount 100% by mass).
[Composition] [Content (% by mass)]
・Niacinamide 5.0
・Hydrogenated polyisobutene 10.0
・ Dipotassium glycyrrhizinate 1.0
・Vaseline 8.0
・Di(phytosteryl/octyldodecyl) lauroyl glutamate 12.0
・Dimer dilinoleic acid (phytosteryl/isostearyl/cetyl/stearyl/behenyl) 4.0
・Dimethicone 6.0
・1,2-Pentanediol 3.0
・Dipropylene glycol 7.0
・ Concentrated glycerin 9.0
・Polyethylene glycol 6000 [molecular weight: 6000] 1.0
・Sodium hyaluronate 0.5
・Behenyl alcohol 2.0
・ Polyglyceryl monostearate 3.0
・Tocopherol 0.5
・Astaxanthin 0.2
・Water-soluble collagen 1.0
・Hydrolyzed collagen solution (derived from fish) 1.0
・N-acetyl-L-hydroxyproline 1.0
・Citric acid 0.7
・Sodium citrate appropriate amount ・Phenoxyethanol 0.3
・Remaining amount of purified water

Claims (11)

Niacinamide having a content of 3% by mass or more relative to the total mass of the water-in-oil cosmetic;
an ultraviolet absorber that absorbs ultraviolet rays in the UV-A region;
a water-soluble moisturizer having a content of 3% by mass or more relative to the total mass of the water-in-oil cosmetic and an IOB value of 2.4 or more;
a silicone surfactant;
an oil containing wax;
water having a content of 20% by mass or more relative to the total mass of the water-in-oil cosmetic;
A water-in-oil type cosmetic containing Does not contain a water-soluble moisturizing agent with an IOB value of 2.1 or less, or contains less than 3% by mass of a water-soluble moisturizing agent with an IOB value of 2.1 or less based on the total mass of the water-in-oil cosmetic. , The water-in-oil type cosmetic according to claim 1. The water-in-oil according to claim 1 or 2, wherein the content of the ultraviolet absorber that absorbs ultraviolet rays in the UV-A region is 2% by mass or more with respect to the total mass of the water-in-oil cosmetic. mold cosmetics. The ultraviolet absorber that absorbs ultraviolet rays in the UV-A region is at least one selected from the group consisting of hexyl diethylaminohydroxybenzoylbenzoate, bisethylhexyloxyphenolmethoxyphenyltriazine, and t-butylmethoxydibenzoylmethane. The water-in-oil type cosmetic according to any one of claims 1 to 3. The oil according to any one of claims 1 to 4, wherein the water-soluble moisturizer having an IOB value of 2.4 or more contains at least one selected from glycerin and 1,3-butylene glycol. Aqueous cosmetics. The water-in-oil type cosmetic according to any one of claims 1 to 5, wherein the content of the silicone surfactant is 1% by mass or more relative to the total weight of the water-in-oil type cosmetic. fee. The water-in-oil type cosmetic according to any one of claims 1 to 6, wherein the silicone surfactant comprises a polyether-modified silicone surfactant having a branched silicone chain. The water-in-oil cosmetic composition according to any one of claims 1 to 7, comprising an ultraviolet absorber that absorbs ultraviolet rays in the UV-B region. According to any one of claims 1 to 8, wherein the total content of UV absorbers contained in the water-in-oil cosmetic is 8% by mass or more relative to the total mass of the water-in-oil cosmetic. The water-in-oil cosmetic described above. The water-in-oil cosmetic composition according to any one of claims 1 to 9, wherein the wax content is 3% by mass or more relative to the total mass of the water-in-oil cosmetic composition. The water-in-oil type cosmetic according to any one of claims 1 to 10, which is a solid cosmetic.