JP2005247722A - Oil-in-water type emulsion composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an oil-in-water type emulsion composition having excellent dispersion stability and good sense of use. <P>SOLUTION: This oil-in-water type emulsion composition comprises a water phase, an oil phase dispersed in the water phase and powder dispersed in the oil phase. The oil phase comprises ≥50 mass% silicone oil based on the whole amount of the oil phase, an amphiphilic material compatible with the silicone oil and having ≤5 HLB, and an acryl silicone represented by formula (I) [wherein, R is a 10-20C alkyl group; (a), (b) and (c) are each ≥0.2 and satisfy the equation of (a)+b+c=1] as a dispersant of the powder. Preferably, the composition contains 10-30 mass% acryl silicone represented by formula (I) based on the amount of the powder. The composition can contain two or more kinds of powders. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an oil-in-water emulsion composition, and in particular, to the improvement of its dispersion stability and feeling of use.

Conventionally, various cosmetics containing inorganic powders such as titanium oxide and zinc oxide have been widely used. As these cosmetics, oil-in-water emulsion compositions are used preferably in cosmetics such as emulsions, creams, and emulsified foundations because they have a fresh and refreshing feeling.
On the other hand, an oil-in-water emulsified composition containing a hydrophobized powder obtained by hydrophobizing the surface of an inorganic powder such as titanium oxide or zinc oxide has been developed. Since the hydrophobized powder has high water resistance on the skin and good makeup lasting, by blending it, it is possible to obtain a composition having excellent feeling after use as well as feeling during use.

In a system in which fine powder particles are dispersed in the composition together with such emulsified particles, it is an issue to obtain sufficient dispersion stability as a product. That is, there is a demand for a technique for preventing dispersion of coalesced particles, aggregation of fine particles and sedimentation due to aging, temperature change, etc., and imparting dispersion stability (Japanese Patent Publication No. 7-94366, Japanese Patent Application Laid-Open No. Hei. 8-310940).
Japanese Patent Publication No. 7-94366 JP-A-8-310940

However, in the prior art, particularly when a plurality of hydrophobized powders are blended, there is room for further improvement in dispersion stability and usability.
The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to provide an oil-in-water emulsion composition having excellent dispersion stability and good usability.

（一般式（I）中、Ｒは炭素数１０〜２０未満のアルキル基、ａ＋ｂ＋ｃ＝１、ａ，ｂ，ｃ共に０．２以上、ｎは５〜１００の整数である） As a result of intensive studies by the present inventors to achieve the above object, the powder is sufficiently dispersed in advance in an oil phase component containing silicone oil as a main component and a specific acrylic silicone and an amphiphilic substance, By mixing and emulsifying this with an aqueous phase, it was found that an oil-in-water emulsified composition excellent in use feeling and dispersibility of the powder after application on the skin was obtained, and the present invention was solved. It was.
That is, the oil-in-water emulsion composition according to the present invention includes an aqueous phase, an oil phase dispersed in the aqueous phase, and a powder dispersed in the oil phase,
The oil phase is represented by the following general formula (I) as a dispersant of 50 wt% or more of silicone oil based on the total amount of the oil phase, an HLB5 or less amphiphile compatible with silicone oil, and the powder. And acrylic silicone.
(Chemical formula 1)

(In general formula (I), R is an alkyl group having 10 to less than 20 carbon atoms, a + b + c = 1, a, b and c are both 0.2 or more, and n is an integer of 5 to 100)

In the composition, it is preferable that the powder contains 10 to 30% by mass of the acrylic silicone represented by the general formula (I).
The composition can contain two or more kinds of powders.
The composition preferably further includes one or more thickeners selected from succinoglycan, xanthan gum and acrylamide copolymer.
The composition preferably further comprises one or more emulsifying aids selected from carboxymethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, and gelatin.

According to the oil-in-water emulsified composition of the present invention, a powder is sufficiently dispersed in the oil phase, an oil phase containing 50% by mass or more of silicone oil based on the total amount of the oil phase is used, and a specific acrylic silicone And an amphiphilic substance can be used to obtain an oil-in-water emulsified composition excellent in use feeling and powder dispersibility after application on the skin.
The composition can contain two or more kinds of powders.
Furthermore, by adding a thickening agent having salt resistance, the dispersion stability of the powder can be further improved, and sedimentation and creaming of the emulsified particles over time can be prevented. Things are obtained.
Further, by adding one or more emulsification aids selected from carboxymethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, and gelatin, the temperature stability of the emulsion and the dispersion stability of the powder are further improved. Can do.

The oil-in-water emulsion composition of the present invention is prepared by pre-mixing powder in an oil phase, finely pulverizing the powder with a wet disperser such as a bead mill, and mixing and emulsifying the obtained powder dispersion with an aqueous phase. As a result, the oil phase is emulsified and dispersed in the aqueous phase, and further, the powder is dispersed in a state where the secondary aggregates are sufficiently crushed in the emulsified and dispersed oil phase. There are few, fresh and refreshing feelings, and the dispersion state of the powder on the skin after application is good. When an ultraviolet protective powder such as titanium oxide or zinc oxide is used, a high ultraviolet shielding effect is obtained, and when a colorant such as iron oxide is used, there is no color unevenness and a beautiful finish is obtained.
In order to improve the dispersion stability of the powder and prevent aggregation, a dispersant is added when the powder is finely pulverized and dispersed in the oil phase. At this time, an appropriate combination of the dispersant and the oil phase component is necessary so that the dispersant can sufficiently cover the powder particles and prevent aggregation, but the following combinations are particularly remarkable for the dispersion stability of the powder. It is effective for.

（一般式（I）中、Ｒは炭素数１０〜２０のアルキル基、ａ＋ｂ＋ｃ＝１、ａ，ｂ，ｃ共に０．２以上、ｎは５〜１００の整数である）
特にＲ^２がイソステアリル基であることが好ましい。 A system in which an acrylic silicone of the following general formula (I) is added as a dispersant to an oil phase containing 50% by mass or more of silicone oil based on the total amount of the oil phase:
(Chemical formula 2)

(In general formula (I), R is an alkyl group having 10 to 20 carbon atoms, a + b + c = 1, a, b and c are both 0.2 or more, and n is an integer of 5 to 100)
In particular, R ² is preferably an isostearyl group.

The above system stably disperses the powder, and the oil-in-water emulsion composition of the present invention to which the powder is applied exhibits excellent stability without agglomeration of the powder.
The blending amount of the acrylic silicone of the general formula (I) is preferably 0.1 to 50% by mass with respect to the total amount of the oil phase component. If it is less than 0.1% by mass, the dispersion may be insufficient. If it exceeds 50% by mass, the feeling in use at the time of coating may be deteriorated, which is not preferable.
Moreover, it is suitable that the compounding quantity of the acrylic silicone of the said general formula (I) is 10-30 mass% with respect to powder. If it is less than 10% by mass, dispersion may be insufficient.

Examples of the silicone oil used as the oil phase component include dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, decamethylpolysiloxane, dodecamethylpolysiloxane, tetramethyltetrahydrogenpolysiloxane, and cyclotetradimethylsiloxane. And linear or cyclic polysiloxanes such as cyclopentadimethylsiloxane.
In addition, the oil phase may contain any component selected from oils and fats, waxes, hydrocarbons, higher fatty acids, higher alcohols, synthetic ester oils, natural ester oils and the like as oil phase components other than silicone oil. It is not particularly limited as long as the effects of the present invention are not impaired.

When the powder is dispersed in the oil phase, when the acrylic silicone of the above general formula (I) is used as a dispersant, the powder may be either untreated or surface hydrophobized. In consideration of functions such as holding, it is preferable to perform surface hydrophobization treatment. As specific methods for these treatments, the surface of the inorganic powder particles is treated with, for example, methylhydrogenpolysiloxane, dimethylpolysiloxane, silicones such as alkyl-modified silicone resin, dextrin fatty acid ester, higher fatty acid, higher alcohol, fatty acid ester, metal Hydrophobized soaps, alkyl phosphate ethers, fluorine compounds, or hydrocarbons such as squalane and paraffin by a wet method using a solvent, a gas phase method, a mechanochemical method, etc., and the average particle size is It is necessary to be smaller than that of the emulsified particles that are the oil phase. Examples of inorganic powder particles to be hydrophobized include titanium oxide, zinc oxide, talc, mica, sericite, kaolin, titanium mica, black iron oxide, yellow iron oxide, bengara, ultramarine, bitumen, chromium oxide, chromium hydroxide. And silica.
The blending amount of the powder varies depending on the form of formulation, but in the case of an emulsion foundation, it is preferably about 10 to 60% by mass, and in the case of a protector (milky sunscreen), it is preferably about 10 to 35% by mass.

  Furthermore, in order to improve powder dispersion stability and emulsification stability during and after emulsification, it is effective to reduce the interfacial tension by blending the oil phase with an amphiphilic substance of HLB 5 or less. Moreover, since this amphiphilic substance needs to be compatible with the main component silicone oil, POE-modified siloxane, isostearic acid, and the like are main substances. The compounding amount of the amphiphilic substance is preferably 0.05 to 10% by mass, particularly 0.1 to 5% by mass of the oil phase component. If it is less than 0.05% by mass, the emulsion stability may be insufficient, and if it exceeds 10% by mass, the feel during use may be deteriorated or the phase may be changed to a water-in-oil type.

As described above, when the composition of the present invention is produced, a wet disperser having a high crushing force, such as a bead mill, is prepared by previously blending a powder and a dispersant for the powder into the oil component of the oil phase. Then, the powder is finely pulverized, and the obtained powder dispersion is mixed and emulsified with a water mixer with a homomixer.
At this time, if there are powder particles having a particle size larger than the generated emulsified particle size (emulsified oil droplet size), a part of the powder is transferred from the emulsified oil phase to the aqueous phase by the homomixer treatment, and the aggregates Therefore, the average particle size of the powder needs to be smaller than the average particle size of the emulsified particles that are the oil phase. For example, when using a bead mill, by increasing the residence time of the dispersion in the mill, that is, by increasing the number of passes, the particle size of the crushed powder can be made sufficiently small, and a crushed powder sufficiently smaller than the emulsified particle size can be obtained. . In particular, when an ultraviolet scattering agent is used as the powder, the average particle size after crushing with a wet disperser is preferably 100 nm or less.

  As the emulsifier used for emulsification, a hydrophilic surfactant is preferable because it has low solubility in the oil phase and good temperature stability, and is composed of one or two or more types having a total HLB of 10 or more. Those are preferred. For example, glycerin or polyglycerin fatty acid esters, propylene glycol fatty acid esters, POE sorbitan fatty acid esters, POE sorbite fatty acid esters, POE glycerin fatty acid esters, POE fatty acid esters, POE alkyl ethers, POE alkyl phenyl ethers, POE 1 type or 2 types selected from POP alkyl ethers, POE castor oil or hardened castor oil derivatives, POE beeswax and lanolin derivatives, alkanolamides, POE propylene glycol fatty acid esters, POE alkylamines, POE fatty acid amides, etc. Blend the above. As a compounding quantity, it is preferable that it is 0.5-5 mass% with respect to the composition whole quantity.

Further, by incorporating one or more emulsification aids selected from carboxymethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, and gelatin, the temperature stability of the emulsion and the dispersion stability of the powder are further improved. . As a compounding quantity, it is preferable that it is 0.1-1.0 mass% with respect to the composition whole quantity. When the amount is less than 0.1% by mass, the above effect may not be sufficient, and when it exceeds 1.0% by mass, the use feeling tends to be poor.
And, by adding thickener with salt resistance, especially succinoglycan, xanthan gum or acrylamide copolymer, it is stable against sedimentation of emulsion oil droplets over time, creaming, and stability against powder aggregation. Improved. This is because when a normal thickener is used, the salt that gradually elutes over time from the fine inorganic powder particles to the aqueous phase acts on the thickener to reduce the viscosity, but salt resistance such as succinoglycan This is considered to be because when the thickener excellent in the above is used, it is not affected by the eluted salt and prevents sedimentation of the emulsified particles over a long period of time. As a compounding quantity of the thickener which has salt tolerance, 0.1-1 mass% is preferable with respect to the composition whole quantity. When the amount is less than 0.1% by mass, the above effect is not sufficient, and when it exceeds 1% by mass, the feeling of use may be deteriorated, for example, a twist may occur.
Moreover, it is particularly preferable to use succinoglycan because of its large holding power against temperature changes and a large yield value, and it is excellent in usability effects such as having no powderiness and a fresh feeling of use.

（式中、Ｇｌｕｃはグルコース単位を、Ｇａｌａｃはガラクトース単位を表す。また．括弧内の表示は糖単位同士の結合様式を表す。例えば（β１，４）は，β１−４結合を表す。） Succinoglycan is a kind of polysaccharide derived from microorganisms. More specifically, in addition to saccharide units derived from galactose and glucose, succinic acid and pyruvic acid, acetic acid as an optional component, or of these acids It means a polysaccharide derived from a microorganism containing a unit derived from a salt.
More specifically, the succinoglycan has an average molecular weight of about 1 galactose unit: 1, glucose unit: 7, succinic acid unit: 0.8 and pyruvic acid unit: 1 and may contain an optional acetic acid unit. It is a water-soluble polymer represented by the following structural formula of 6 million.
(Chemical formula 3)

(In the formula, Gluc represents a glucose unit, and Galac represents a galactose unit. Also, the indication in parentheses represents a binding mode between sugar units. For example, (β1, 4) represents a β1-4 bond.)

  Examples of the microorganisms that supply the succinoglycan include bacteria belonging to the genus Pseudomonas, Rhizobium, Alkaligenes, or Agrobacterium. Among these bacteria, Agrobacterium tumefaciens I-736, which is a bacterium belonging to the genus Agrobacterium, was deposited with the Collection Organization of the Parties to Microbial Cultures (CNCM) on March 1, 1988 in accordance with the Budapest Treaty. Publicly available at ] Is particularly preferred as a source of succinoglycan.

Succinoglycan can be produced by culturing these microorganisms in a medium. More specifically, carbon sources such as glucose, sucrose, and starch hydrolysates; organic nitrogen sources such as casein, caseinate, vegetable powder, yeast extract, and corn steep liquor (CSL); metal sulfates and phosphates It can be produced by culturing the above microorganisms in a medium containing inorganic salts such as salts and carbonates and optional trace elements.
In addition, succinoglycan can be blended as it is in the emulsified composition, as well as decomposition products such as acid degradation, alkali degradation, enzyme degradation, and ultrasonic treatment can be similarly blended as necessary.

  Examples of the acrylamide copolymer include vinylpyrrolidone / 2-acrylamido-2-methylpropanesulfonic acid copolymer, dimethylacrylamide / 2-acrylamido-2-methylpropanesulfonic acid copolymer, acrylic acid amide / 2-acrylamide. 2-methylpropanesulfonic acid copolymer, polyacrylic acid amide and sodium polyacrylate mixture, sodium acrylate / 2-acrylamido-2-methylpropanesulfonic acid copolymer, ammonium polyacrylate, polyacrylamide / acrylic Examples thereof include ammonium acid copolymer and acrylamide / sodium acrylate copolymer.

In the composition of the present invention, various components usually used in cosmetics, for example, a moisturizer, an ultraviolet absorber, an organic powder, a pH adjuster, a neutralizer, an antioxidant, Preservatives, antibacterial agents, drugs, plant extracts, fragrances, pigments and the like can be blended.
Examples of the humectant include polyhydric alcohols such as glycerin, diethylene glycol, butylene glycol, and polyethylene glycol, amino acids, nucleic acids, proteins such as collagen and elastin, mucopolysaccharides such as hyaluronic acid and chondroitin sulfate, and the like.
When succinoglycan is blended as a thickener, in some cases, the composition may be distorted when applied to the skin. In order to improve this, it is particularly suitable to use dynamite glycerin as a moisturizing agent, and the feeling of use can be improved by eliminating the distortion of the powder.

  Examples of ultraviolet absorbers include benzoic acid ultraviolet absorbers such as paraaminobenzoic acid, anthranilic acid ultraviolet absorbers such as methyl anthranilate, salicylic acid ultraviolet absorbers such as octyl salicylate, phenyl salicylate and homomethyl salicylate, and paramethoxy cinnamon. Isopropyl acid, octyl paramethoxycinnamate, 2-ethylhexyl paramethoxycinnamate, glyceryl mono-2-ethylhexanoate diparamethoxycinnamate, [4-bis (trimethylsiloxy) methylsilyl-3-methylbutyl] -3 , 4,5, -trimethoxycinnamic acid ester, etc., cinnamic acid UV absorbers, urocanic acid, ethyl urocanate, 2-phenyl-5-methylbenzoxazole, 2- (2′-hydroxy-5 ′) -Methylphenyl) benzotriazole, 4-tert Butyl-4'-methoxybenzoyl methane, bis (Resorushiniru) triazine.

Examples of the organic powder include nylon powder, polyethylene powder, polymethylsilsesquioxane powder, silicone elastomer powder, and acrylic resin powder.
Examples of the pH adjuster include lactic acid, citric acid, sodium citrate, glycolic acid, succinic acid, tartaric acid, dl-malic acid, potassium carbonate, sodium hydrogen carbonate, ammonium hydrogen carbonate and the like.
Examples of the antioxidant include ascorbic acid, α-tocopherol, dibutylhydroxytoluene, butylhydroxyanisole and the like.
Examples of preservatives and antibacterial agents include paraoxybenzoic acid esters, phenoxyethanol, benzoic acid, salicylic acid, carboxylic acid, sorbic acid, parachlormetacresol, hexachlorophene, benzalkonium chloride, chlorhexidine chloride, trichlorocarbanilide, and photosensitizers. Can be mentioned.

  The oil-in-water emulsion composition of the present invention can be widely applied to cosmetics, pharmaceuticals, and quasi drugs applied to the outer skin. Moreover, the product form is also arbitrary, and can be used as an emulsion, cream, emulsified foundation, emulsified sunscreen or the like.

Hereinafter, preferred embodiments of the present invention will be described in more detail. In addition, this invention is not limited by this. Further, the blending amount (%) is mass% unless otherwise specified.
<Dispersed state of powder and feel of use>
Based on the formulation in Table 1, oil-in-water emulsion compositions (Test Examples 1 to 4) were produced by various production methods. The composition of each test example was applied to the skin of a subject, and sensory evaluation of the feeling of use at the time of application was performed.
(Table 1)
Prescription
Oil phase component
(1) Fine particle titanium oxide coated with alkyl-modified silicone resin 4.0
(2) Titanium oxide coated with alkyl-modified silicone resin 6.0
(3) Alkyl modified silicone resin coated iron oxide red 0.4
(4) Alkyl-modified silicone resin coated iron oxide yellow 2.0
(5) Alkyl-modified silicone resin coated iron oxide black 0.2
(6) Acrylic silicone represented by general formula (I) 3.0
(7) POE-modified siloxane 1.0
(EO modification rate 20%, molecular weight 6000-8000)
(8) Cyclopentadimethylsiloxane 10.0
(9) Cetyl octanoate 1.0
(10) Methylphenylpolysiloxane 3.4
Water phase component
(11) 1,3-butylene glycol 5.0
(12) EO-PO block copolymer 1.5
(EO / PO: 200 mol / 40 mol)
(13) Carboxymethylcellulose sodium 0.15
(14) Succinoglycan 0.35
(15) Ion exchange water remaining
(16) EDTA.3Na ₂ H ₂ O 0.1
(17) Dipropylene glycol 3.0
(18) Methylparaben 0.15

Test example 1
Production method: Oil phase components (1) to (10) are mixed, and the mixture is treated in a bead mill with 5 passes to sufficiently crush and disperse the hydrophobized titanium oxide, and then (11) to (18). While adding a homomixer to the aqueous phase consisting of the aqueous phase components of
Test example 2
Production method: Oil phase components (1) to (10) are mixed, and the mixture is treated in a bead mill with 3 passes to sufficiently crush and disperse the hydrophobized titanium oxide, and then (11) to (18). While adding a homomixer to the aqueous phase consisting of the aqueous phase components of

Test example 3
Production method: Oil phase components (1) to (10) are mixed, and the mixed solution is added to the aqueous phase composed of the aqueous phase components (11) to (18) while applying a homomixer.
Test example 4
Production method: After mixing the oil phase components (1) to (10), an oil-in-water emulsion is obtained by adding the water phase composed of the water phase components (11) to (18) while applying a homomixer. . On the other hand, hydrophobized fine particle titanium oxide (average particle size 100 nm) that is sufficiently finer than the emulsified particle size after homomixer treatment is dispersed in ion-exchanged water, and the resulting oil-in-water emulsion is dispersed with a disper. To do.

Evaluation criteria for the feeling of use at the time of application ◎: 80% or more of the subjects answered that there was no powder feeling and fresh and refreshed feeling ○: 50% or more and less than 80% of the subjects were feeling fresh and refreshed without powder feeling △: 30% or more and less than 50% of the subjects answered that there was no powder feeling and a fresh and refreshing feeling ×: Less than 30% of the subjects answered that there was no powder feeling and the feeling was refreshing and refreshing

The evaluation results for each test example are shown in Table 2.
(Table 2)
Test Example 1 Test Example 2 Test Example 3 Test Example 4
Usability when applying ◎ △ × △
As is clear from Table 2, the test example 1 had a structure in which the hydrophobic powder sufficiently crushed by the bead mill was dispersed in the emulsified oil phase. Furthermore, since the dispersion state on the skin after application | coating is good, it was excellent also in the ultraviolet-ray shielding effect.
On the other hand, in Test Example 2, the powder was not sufficiently crushed by the bead mill, and in Test Example 3, the pulverization treatment was not performed. It moved to the water phase and aggregates were generated. For this reason, there was a feeling of powder at the time of application.

In Test Example 4, although the primary particle size of the fine powder particles was sufficiently finer than the emulsified particle size, a part of the powder became secondary particles larger than the emulsified particle size and existed in the aqueous phase. For this reason, there was a feeling of powder at the time of application.
From the above, in order to obtain an oil-in-water emulsion composition with a good feeling of use, it is necessary to pulverize the hydrophobic powder sufficiently finely and disperse it in the emulsified oil phase. It is preferable to finely pulverize the powder in advance with a bead mill or the like and disperse it in the oil phase, and then mix and emulsify the resulting powder dispersion with the aqueous phase.

<Powder dispersion stability>
Based on the formulation in Table 3, oil-in-water emulsion compositions (Test Examples 5 to 10) were produced by the same production method as in Test Example 1 described above. The compositions of these test examples were placed in a 50 ml sample tube (diameter 3 cm), rotated at room temperature for 4 hours at a speed of 45 rpm, and the degree of powder aggregation was visually evaluated.
Evaluation Criteria for Dispersion Stability of Powder ○: No powder aggregate was visually observed.
Δ: Some powder agglomerates were visually observed.
X: A considerable amount of powder aggregate was visually observed.
The evaluation results for each test example are shown in Table 3.

(Table 3)
Test example
Formula 5 6 7 8 9 10 11 12
Oil phase component
(1) Methyl hydrogen polysiloxane coated fine particle titanium oxide
4.0 4.0 4.0 4.0 4.0 4.0 4.0 4.0
(2) Titanium oxide coated with methyl hydrogen polysiloxane
6.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0
(3) Methyl hydrogen polysiloxane coated iron oxide red
0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4
(4) Methyl hydrogen polysiloxane coated iron oxide yellow
2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0
(5) Methyl hydrogen polysiloxane coated iron oxide black
0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2
(6) Acrylic silicone represented by general formula (I) (I) * 1
3.0 3.0 3.0 3.0 − − − 3.0
(7) Acrylic silicone (II) * 2
− − − − 3.0 − − −
(8) Sorbitan sesquiisostearate
− − − − − 3.0 − −
(9) Trimethylsiloxysilicic acid
− − − − − − 3.0 −
(10) POE-modified siloxane (EO modification rate 20%, molecular weight 6000 to 8000)
1.0 1.0 1.0 1.0 1.0 1.0 1.0 −
(11) Cyclopentadimethylsiloxane
10.0 7.0 3.0 − 10.0 10.0 10.0 10.0
(12) Cetyl octanoate 1.0 − − − 1.0 1.0 1.0 1.0
(13) Methylphenyl polysiloxane
3.4 3.4 3.4 − 3.4 3.4 3.4 3.4
(14) Octyl paramethoxycinnamate
− 4.0 8.0 14.4 − − − −
Water phase component
(15) 1,3-butylene glycol
5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0
(16) EO-PO block copolymer (EO / PO: 200 mol / 40 mol)
1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5
(17) Sodium carboxymethyl cellulose
0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15
(18) Succinoglycan 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35
(19) Ion-exchanged water Residue Residue Residue Residue Residue Residue Residue Residue Residue
(20) EDTA · 3Na ₂ H ₂ O
0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
(21) Dipropylene glycol
3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0
(22) Methylparaben 0.15 0.15 0.15 0.15 0.15 0.15 0.15 0.15
Powder dispersion stability ○ ○ △ × × × × △
* 1 In general formula (I), R is isostearyl group (C ₁₈ ) * 2 In general formula (I), R is ethylhexyl group (C ₈ )

As is apparent from Table 3, it is understood that good powder dispersion stability can be obtained only when a specific dispersant is used for a specific oil phase. That is, when the acrylic silicone of the present invention is blended as a dispersant in an oil phase containing silicone oil as a main component (Test Examples 5 and 6), good powder dispersion stability can be obtained. On the other hand, when the main component is other than silicone oil (Test Examples 7 and 8), and when acrylic silicone and other dispersants other than the present invention are used (Test Examples 9 to 11), the dispersion stability is lowered. I understand that Further, when no amphiphilic substance was used (Test Example 12), the dispersion stability also decreased.
As described above, the oil-in-water emulsion composition of the present invention has a dispersion stability by blending the acrylic silicone represented by the above general formula (I) as a dispersant in an oil phase containing 50% by mass or more of silicone oil. It can be seen that the dispersion stability is further improved by using an amphiphilic substance.

<Stability of emulsified particles over time>
Based on the formulation in Table 4, oil-in-water emulsion compositions (Test Examples 13 to 16) were produced by the same production method as in Test Example 1 described above. About the composition of each of these test examples, the state of the emulsion after the lapse of 1 month was visually evaluated.
Evaluation criteria for stability over time of emulsified particles ○: The composition maintained a dispersed state.
X: The emulsified particles in the composition were settled and united to separate the oil phase.
The evaluation results for each test example are shown in Table 4.

(Table 4)
Test example
Prescription 13 14 15 16
Oil phase component
(1) Titanium oxide treated with aluminum stearate
4.0 4.0 4.0 4.0
(2) Titanium oxide coated with methyl hydrogen polysiloxane
6.0 6.0 6.0 6.0
(3) Methyl hydrogen polysiloxane coated iron oxide red
0.4 0.4 0.4 0.4
(4) Methyl hydrogen polysiloxane coated iron oxide yellow
2.0 2.0 2.0 2.0
(5) Methyl hydrogen polysiloxane coated iron oxide black
0.2 0.2 0.2 0.2
(6) Acrylic silicone represented by general formula (I) 3.0 3.0 3.0 3.0
(7) POE-modified siloxane 1.0 1.0 1.0 1.0
(EO modification rate 20%, molecular weight 6000-8000)
(8) Cyclopentadimethylsiloxane 10.0 10.0 10.0 10.0
(9) Cetyl octanoate 1.0 1.0 1.0 1.0
(10) Methylphenylpolysiloxane 3.4 3.4 3.4 3.4
Water phase component
(11) 1,3-butylene glycol 5.0 5.0 5.0 5.0
(12) EO-PO block copolymer 1.5 1.5 1.5 1.5
(EO / PO: 200 mol / 40 mol)
(13) Sodium carboxymethylcellulose 0.15 0.15 0.15 0.15
(14) Succinoglycan 0.35 − − −
(15) Xanthan gum − 0.35 − −
(16) Dimethylacrylamide / 2-acrylamide-2-
Methylpropanesulfonic acid copolymer − − 0.35 −
(17) Polyacrylic acid Na − − − 0.35
(18) Ion-exchanged water Residual Residual Residual Residual Residual
(19) EDTA · 3Na ₂ H ₂ O 0.1 0.1 0.1 0.1
(20) Dipropylene glycol 3.0 3.0 3.0 3.0
(21) Methylparaben 0.15 0.15 0.15 0.15
Stability of emulsified particles over time ○ ○ ○ △

  As is clear from Table 4, when succinoglycan, xanthan gum, and acrylamide copolymer are used as thickeners, the stability over time is particularly good, whereas when other thickeners are used. The stability over time is poor. This is because when an ordinary thickener is used, a salt that gradually elutes over time from the inorganic powder particles (titanium oxide in Table 4) to the aqueous phase acts on the thickener to lower the viscosity. Conceivable. On the other hand, when a thickener excellent in salt resistance such as succinoglycan is used, it is considered that it is not affected by the eluted salt and prevents sedimentation of the emulsified particles over a long period of time.

Hereinafter, although the suitable example of the cosmetics using the composition of this invention is shown, this invention is not limited to these formulation examples at all.
Formulation Example 1: Suncut oil-in-water emulsion
(1) Hydrophobized titanium dioxide 7.5
(2) Acrylic silicone represented by the general formula (I) 1.5
(3) POE-modified methylpolysiloxane 1
(EO modification rate 20%, molecular weight 6000-8000)
(4) Decamethylpentacyclosiloxane 10
(5) Octyl paramethoxycinnamate 5
(6) PEG-60 hydrogenated castor oil 2
(7) Dynamite Glycerin 6
(8) Succinoglycan 0.3
(9) Carboxymethylcellulose 0.3
(10) Ethanol 5
(11) Ion-exchanged water Residual manufacturing method (1) to (5) are mixed, dispersed and crushed by a bead mill, and then added to a water phase in which (6) to (11) are dissolved while applying a homomixer.

Formulation Example 2: Oil-in-water emulsion
(1) Hydrophobized fine particle titanium oxide 5
(2) Hydrophobized zinc oxide 5
(3) Acrylic silicone represented by general formula (I) 2
(4) POE-modified methylpolysiloxane 1
(EO modification rate 20%, molecular weight 6000-8000)
(5) Decamethylpentacyclosiloxane 10
(6) Octyl paramethoxycinnamate 5
(7) PEG-60 hydrogenated castor oil 2
(8) Dynamite glycerin 6
(9) Xanthan gum 0.3
(10) Carboxymethylcellulose 0.3
(11) Ethanol 5
(12) Ion-exchanged water Residual manufacturing method (1) to (6) are mixed, dispersed and crushed by a bead mill, and then added to a water phase in which (7) to (12) are dissolved while applying a homomixer.

Formulation example 3: UV protection whitening serum
(1) Hydrophobized fine particle titanium oxide 5
(2) Acrylic silicone represented by general formula (I) 1
(3) Isostearic acid 1
(4) Decamethylpentacyclosiloxane 10
(5) Octyl paramethoxycinnamate 5
(6) PEG-60 hydrogenated castor oil 2
(7) Dynamite Glycerin 6
(8) Succinoglycan 0.3
(9) Carboxymethylcellulose 0.3
(10) Ethanol 6
(11) Citric acid appropriate amount
(12) Sodium citrate appropriate amount
(13) Ascorbic acid glycoside 2
(14) Caustic potash
(15) Ion-exchanged water Residual production method (1) to (5) are mixed, dispersed and crushed by a bead mill, and then added to a water phase in which (6) to (15) are dissolved while applying a homomixer.

Formulation Example 4: Oil-in-water emulsion foundation
(1) Hydrophobized titanium dioxide 10
(2) Hydrophobized talc 3
(3) Hydrophobized yellow iron oxide 0.8
(4) Hydrophobized black iron oxide 0.16
(5) Hydrophobized Bengala 0.36
(6) Acrylic silicone represented by general formula (I) 1
(7) POE-modified methylpolysiloxane 1
(EO modification rate 20%, molecular weight 6000-8000)
(8) Decamethylpentacyclosiloxane 10
(9) Octyl paramethoxycinnamate 5
(10) PEG-60 hydrogenated castor oil 2
(11) Dynamite glycerin 6
(12) Xanthan gum 0.3
(13) Carboxymethylcellulose 0.3
(14) Ethanol 5
(15) Ion-exchanged water Residual production method (1) to (9) are mixed, dispersed and crushed by a bead mill, and then added to a water phase in which (10) to (15) are dissolved while applying a homomixer.

Formulation Example 5: Oil-in-water emulsion foundation
(1) Hydrophobized titanium dioxide 10
(2) Hydrophobized talc 3
(3) Hydrophobized yellow iron oxide 0.8
(4) Hydrophobized black iron oxide 0.16
(5) Hydrophobized Bengala 0.36
(6) Acrylic silicone represented by general formula (I) 1
(7) POE-modified methylpolysiloxane 1
(EO modification rate 20%, molecular weight 6000-8000)
(8) Decamethylpentacyclosiloxane 10
(9) Octyl paramethoxycinnamate 5
(10) PEG-60 hydrogenated castor oil 2
(11) Dynamite glycerin 6
(12) Dimethylacrylamide / 2-acrylamido-2-methylpropanesulfonic acid copolymer 0.3
(13) Carboxymethylcellulose 0.3
(14) Ethanol 5
(15) Ion-exchanged water Residual production method (1) to (9) are mixed, dispersed and crushed by a bead mill, and then added to a water phase in which (10) to (15) are dissolved while applying a homomixer.

  The cosmetics of each of the above formulation examples had a fresh and refreshing feel, and were excellent in dispersion stability.

Claims (5)

An aqueous phase, an oil phase dispersed in the aqueous phase, and a powder dispersed in the oil phase,
The oil phase is represented by the following general formula (I) as a dispersant of 50 wt% or more of silicone oil based on the total amount of the oil phase, an HLB5 or less amphiphile compatible with silicone oil, and the powder. An oil-in-water emulsified composition comprising an acrylic silicone.
(Chemical formula 1)

(In general formula (I), R is an alkyl group having 10 to 20 carbon atoms, a + b + c = 1, a, b and c are both 0.2 or more, and n is an integer of 5 to 100)   2. The oil-in-water emulsion composition according to claim 1, comprising 10 to 30% by mass of the acrylic silicone represented by the general formula (I) with respect to the powder.   3. The oil-in-water emulsion composition according to claim 1, comprising two or more kinds of powder.   The composition according to any one of claims 1 to 3, further comprising one or more thickeners selected from succinoglycan, xanthan gum and an acrylamide copolymer. Type emulsified composition.   The composition according to any one of claims 1 to 4, further comprising one or more emulsification aids selected from carboxymethylcellulose, hydroxyethylcellulose, hydroxymethylcellulose, and gelatin. Emulsified composition.