JPH038432A - Water-in-oil type emulsified composition - Google Patents

Abstract

PURPOSE:To obtain a useful water-in-oil type emulsified compsn. by incorporating a specified acrylic-silicone graft copolymer into an oily phase and using a specified polyoxyalkylene-modified organopolysiloxane surfactant. CONSTITUTION:An oily agent contg. 50-95wt.% silicone oil having low viscosity and 1-50wt.% acrylic-silicone graft-copolymer obtd. by copolymerizing a dimethylpolysiloxane compd. having a radical-polymerizable group at one terminal of the molecular chain with a radicalpolymerizable monomer based on acrylate, etc., is prepd. and 30-60wt.% of the oily agent is mixed with 0.1-10wt.% polyoxyalkylenemodified organopolysiloxane surfactant represented by formula I or II (where each of G1 and G2 is CH3 or (CH2)pO(C2H4O)m(C3H6O)nR1, a is 5-300 and b is 0-50) and 5-62.9wt.% water to obtain a stable water-in-oil type emulsified compsn. ensuring a good feeling.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a water-in-oil emulsion composition, and more particularly, it has excellent stability over time, forms a highly water-repellent cosmetic film, and is suitable for use. The present invention relates to a water-in-oil emulsion composition that has a good texture and is particularly suitable for cosmetics and the like.

[Conventional technology and its problems]

Emulsified compositions are generally of oil-in-water type (0/W type) and water-in-oil type (
Among these, water-in-oil emulsion compositions have a better affinity for the skin than oil-in-water emulsion compositions, and coat the skin surface with an oil film to prevent water evaporation and improve skin It is used in basic cosmetics because of its properties such as protecting it from dryness and imparting treatment effects to the skin, and it is also used as a base for cosmetics such as makeup cosmetics and pharmaceuticals because it has excellent water repellency and does not cause makeup to come off easily. Widely used.

In water-in-oil (WO type) emulsion compositions, silicone oil is often used as an oil agent in order to obtain a light, non-sticky composition with good water repellency. In addition, when preparing such an emulsified composition, the emulsifier usually includes:
In order to obtain products with good stability over time, lipophilic polyoxyalkylene-modified organopolysiloxane surfactants that have good compatibility with silicone oil are widely used. However, by simply adding this surfactant to an emulsion composition containing a large amount of silicone oil, it has been difficult to obtain a product that is sufficiently stable over time. Therefore, it is necessary to mix wax or organically modified clay mineral as a gelling agent (JP-A No. 61-66752, No. 61-21850).
No. 9) has been attempted, but it has been difficult to obtain a product that satisfies the feel and ease of use and has good stability over time.

[Means to solve the problem]

Under these circumstances, the present inventors conducted extensive research and found that the oil phase component contains a specific acrylic-silicone graft copolymer, and a specific polyoxyalkylene-modified organopolysiloxane surfactant is used as an emulsifier. The present inventors have discovered that an excellent water-in-oil emulsion composition can be obtained by using the agent, which has excellent feel on use, good stability over time, and is highly useful as a base for cosmetics, etc., and has completed the present invention.

That is, the present invention provides a lubricant containing the following components (A) to (C) (A) 30 to 60% by weight of components (a) and (b) (a) 50 to 95% by weight of a low viscosity silicone oil ( b) Acrylic-silicone graft copolymer oil obtained by radical copolymerization of a dimethylpolysiloxane compound having a radically polymerizable group at one end of its molecular chain and a radically polymerizable monomer mainly composed of acrylate and/or methacrylate. Medium 1-50% by weight (B)
General formula (I) or (II) [wherein, Gl and G2 may be the same or different,
CH3 or (CH2)pD(C28,0), (C,H60), respectively. R
+ (p = 1 to 5, m = 1 to 50, n = 0 to 30, R + represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), and X is (CL) po ( C2H40),
(CsHsO), R+ (p.

+n, n and R+ have the same meanings as above),
Indicates the number of a75 to 300, b=o to 50.

However, both G and G are Cl(, and b
Except when = 0. ] (II) [In the formula, G1, G, and X have the same meanings as above, and a
= 1 to 30, b = 0 to 50, C = 5 to 300, and R2 represents an alkyl group having 2 to 20 carbon atoms.

However, both G and G2 are CL, and b: 0
except when ] Provided is a water-in-oil emulsion composition characterized by containing 0.1 to 10% by weight of a polyoxyalkylene-modified organopolysiloxane surfactant represented by (C) 5 to 69.9% by weight of water. It is something to do.

Among the components (A) used in the present invention, the low viscosity silicone oil that is component (a) is not particularly limited, but those having a viscosity of about 50 cs or less can be suitably used. As the viscosity increases, as a result of using a large amount of it, the compatibility with the acrylic-silicone graft copolymer, component (b), decreases, and the viscosity increases.
This is because the oil phase does not become gelled, and it also feels oily to the touch, resulting in an unfavorable feel in use.

Examples of low-viscosity silicone oil include dimethylpolysiloxane with a low degree of polymerization, methylphenylborin 20xane, cyclic octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane, and one of these or Two or more types are appropriately selected and used. Low viscosity silicone oil has a concentration of 50-95% in the oil agent.
(hereinafter simply shown in %). If it is less than 50%, it is not preferable because the smooth feeling of use and high water absorption properties of low viscosity silicone oil are not effectively exhibited.

The acrylic-silicone graft copolymer of component 0)) consists of a dimethylpolysiloxane compound (a) having a radically polymerizable group at one end of its molecular chain, an acrylate and/or
Alternatively, it is synthesized by radical copolymerization with a radically polymerizable monomer (b) mainly composed of methacrylate.

The dimethylpolysiloxane compound (a) having a radically polymerizable group at one end of the molecular chain is represented by the following general formula (1).

Below margin R5 Dimethyl group or hydrogen atom R1: 1 carbon atom having a straight or branched carbon chain interrupted by one or two ether bonds as the case may be
~10 divalent saturated hydrocarbon groups 1:3-300 R1 is 1 carbon atom with a straight or branched carbon chain optionally interrupted by 1 or 2 ether bonds
~10 divalent saturated hydrocarbon groups, specifically -C)12-1(CHJs, +CH
zh+, +CHJsS+CLho, -CL-C)I(C
)ls)-CL--CHzC)120C)lzCH2C
)12-1-CH2CH20CH,CI((CH3)
CH, -1-C)1. CH, OCH, CH20CH2C
Examples include H, CH, -, and the like.

l is in the range of 3 to 300, preferably 5 to 100; if it is less than 3, the compatibility with low viscosity silicone oil will decrease, and the oil phase will not have sufficient thickening and gelling ability; If it exceeds 300, the glass transition point of the resulting acrylic-silicone graft copolymer will be too low, making it impossible to thicken and gel the oil phase.

The dimethylpolysiloxane compound represented by the general formula (1) having a radically polymerizable group at one end of the molecular chain is
Typically, it is obtained by subjecting a (meth)acrylate-substituted chlorosilane compound represented by the following general formula (2) and a terminal hydroxyl group-substituted dimethylpolysiloxane represented by the general formula (3) to a dehydrochloric acid reaction according to a conventional method. However, the synthesis method is not limited to this.

The following are blank spaces (in the formula, R5, R4 and l have the same meanings as above).Specific examples of dimethylpolysiloxane compounds suitably used as dimethylpolysiloxane compounds having a radically polymerizable group at one end of the molecular chain are shown below. Things can be mentioned.

Margin below CH.

On the other hand (b), the radically polymerizable monomer mainly composed of acrylate and/or methacrylate means a compound having one radically polymerizable unsaturated bond in the molecule, and the acrylate and/or methacrylate used is , methyl (meth)acrylate, ethyl (meth)acrylate), n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.
Examples include hydroxyalkyl (meth)acrylates such as meth)acrylate, 2-hydroxyethyl (meth)acrylate, and 2-hydroxypropyl (meth)acrylate, and perfluoroalkyl (meth)acrylates having 1 to 10 fluorocarbon chains. can. In the present invention, the term acrylate and/or methacrylate as the main component means that the total amount of one or more acrylates and/or methacrylates in addition to the above radically polymerizable monomers is 50% or more of the total radically polymerizable monomers. means to occupy the This is acrylate and/or
Alternatively, if the total amount of methacrylate is less than 50%, sufficient thickening and gelling ability, which is the objective of the present invention, cannot be obtained.

In the radically polymerizable monomer of the present invention, various compounds other than the above-mentioned acrylate and/or methacrylate can be used as necessary. These polymerizable monomers include styrene, substituted styrene,
Examples include vinyl acetate, (meth)acrylic acid, maleic anhydride, maleic esters, fumaric esters, vinyl chloride, vinylidene chloride, ethylene, propylene, butadiene, acrylonitrile, and fluorinated olefins.

In the present invention, the polymerization ratio ((a)/ (B))
must be within the range of 1/19 to 2/1.

This is less than 1/19, and the proportion of the dimethylpolysiloxane compound having a radically polymerizable group at one end of the molecular chain (a) is small (if it becomes too much, the proportion of the dimethylpolysiloxane compound having a radically polymerizable group at one end of the molecular chain is too low). Because the compatibility with oil etc. decreases, sufficient thickening and gelling ability of the oil phase cannot be obtained;
Alternatively, if the proportion of the radically polymerizable monomer mainly composed of methacrylate becomes too small, the acrylic-silicone graft copolymer itself has fluidity, making it impossible to thicken and gel the oil phase.

Copolymerization of (a) a dimethylpolysiloxane compound having a radically polymerizable group at one end of its molecular chain and (b) a radically polymerizable monomer mainly composed of acrylate and/or methacrylate is performed using benzoyl peroxide or lauroyl peroxide. The polymerization is carried out in the presence of a conventional radical polymerization initiator such as azobisisobutyronitrile, and any of solution polymerization, emulsion polymerization, suspension polymerization, and bulk polymerization can be applied. Among these, the solution polymerization method is preferred because it allows easy adjustment of the molecular weight of the resulting graft copolymer to an optimal range.

The solvent used is one of aromatic hydrocarbons such as benzene, toluene, and xylene, ketones such as methyl ethyl ketone and methyl isobutyl ketone, esters such as ethyl acetate and isobutyl acetate, and alcohols such as isopropanol and butanol. A mixture of two or more types may be mentioned.

Polymerization reaction at 50-180°C, preferably 60-120°C
The process can be carried out within a temperature range of about 5 to 10 hours under these conditions. The acrylic-silicone graft copolymer produced in this manner has a weight average molecular weight of about 3,000 to about 200,000, more preferably about 5,000 to about 100,000 in terms of polystyrene based GPC. The glass transition temperature is preferably in the range of -30 to +60°C.

The thus obtained acrylic-silicone graft copolymer stabilizes the water-in-oil emulsion composition of the present invention by thickening and gelling the low-viscosity silicone oil, which is the main component of the oil phase. It forms a cosmetic film with excellent water repellency and enhances cosmetic functionality. This acrylic-silicone graft copolymer may be one or two types.
It is possible to use a combination of two or more species, and one to
Contains 50%. If it is less than 1%, sufficient thickening and gelling effects cannot be obtained, and if it exceeds 50%, it feels heavy on the skin and becomes oily, resulting in poor usability and feel, which is not preferable.

In addition to the low-viscosity silicone oil and the acrylic-silicone kraft copolymer, as the oil agent of component (A) of the present invention, oil agents used in ordinary emulsion compositions are blended within a range that does not disturb the uniformity of the oil phase. can do. As such oils, natural oils, vegetable oils, and synthetic oils can be used.Specifically, liquid paraffin, squalane, and other liquid, paste, or solid hydrocarbons, waxes, higher fatty acids, higher alcohols, and esters can be used. , glyceride,
Examples include silicone oil agents other than component (a).

Component (A) is blended in an amount of 30 to 60% in the total composition. 3
If it is less than 0%, the satisfactory effect of the present invention cannot be obtained.

The polyoxyalkylene-modified organopolysiloxane surfactant which is the component (B)a of the present invention has the general formula (I
) or (II), and are called polyether-modified silicones and alkyl polyether-modified silicones, and function as emulsifiers. these are,
Those that are liquid or paste-like at room temperature, particularly those that are water-insoluble are preferred, such as Silicon KF-945A (manufactured by Shin-Etsu Chemical Co., Ltd.), Silicon 5t (-3772C (manufactured by Toshi/Dow Corning Silicone Co., Ltd.), Avil WE- 09
(manufactured by Goldschmidt), etc. Since the main chain of these polyoxyalkylene-modified organopolysiloxane surfactants is a polysiloxane chain, they have good compatibility with the low-viscosity silicone oil and the acrylic-silicone graft copolymer in the oil phase. Emulsion stability can be obtained.

Component (B) is incorporated in the total composition in an amount of 0.1 to 10%, preferably 0.5 to 5%. If it is less than 0.1%, sufficient emulsifying ability cannot be exhibited, and if it exceeds 10%, the water-oil interface becomes too strong, resulting in a feeling of weight and stickiness, which is not preferable.

In addition, water as the component (C) is blended in an amount of 5 to 69.9% in the total composition.

In addition to the above-mentioned essential components, the emulsified composition of the present invention includes commonly used aqueous components and oil-based components, such as humectants, preservatives,
Antioxidants, ultraviolet absorbers, beauty ingredients, fragrances, water-soluble polymers, extender pigments, coloring pigments, bright pigments, organic powders, hydrophobized pigments, tar pigments, etc. should not be used to impair the effects of the present invention. It can be blended within a range.

The water-in-oil emulsion composition of the present invention can be produced by emulsifying according to a conventional method, except that components (a) and (c) of component (A) are dissolved in advance. It can be suitably used as a material.

〔Example〕

The present invention will be further explained below with reference to Examples, but the present invention is not limited to these Examples.

Reference Example 1 Synthesis of acrylic-silicone graft copolymer: 30 g of dimethyl polysiloxane substituted with methacrylate at one end represented by the following chemical formula, 30 g of methyl methacrylate, 5 g of n-butyl methacrylate, 100 g of n-butyl methacrylate, After adding and dissolving 1.5 g of lonitrile,
The reaction was carried out for 5 hours under stirring at a temperature of 80 to 90°C to obtain a viscous solution. This solution was poured into 21 methanol to precipitate the graft copolymer. The precipitate was filtered off and dried to obtain 93 g of a white substance. This material was confirmed by infrared absorption spectrum to be a methacrylate polymer to which dimethylpolysiloxane was grafted, and the weight average molecular weight in terms of polystyrene by GPC was approximately 16,000, and the glass transition temperature was 18°C. .

Reference Example 2 Synthesis of acrylic-silicone graft copolymer: 40 g of dimethyl polysiloxane substituted with methacrylate at one end represented by the following chemical formula The results are shown in Table 2.

A graft copolymer was obtained under the same conditions as in Reference Example 1 from 40 g of methyl methacrylate and 20 g of 2-ethylhexyl acrylate. The weight average molecular weight of this product in terms of polystyrene by GPC is about 15.000,
Moreover, the glass transition temperature was 25°C.

Example 1 Creamy water-in-oil emulsion compositions having the compositions shown in Table 1 were prepared, and their stability over time was evaluated.

(Manufacturing method) A, tL portions (4) to (6) are gradually added with solutions of components (7), (8) and part of the component (support) and stirred and mixed to obtain a gel-like emulsion.

B. Dissolve components (1) to (3) uniformly, add 8 to this, and bring to 70°C.

The remainder of C0 component (9), α0, and (support) are mixed and heated to melt at 70°C.

Add C to D and B and emulsify, then add component αD and cool.
A wood-in-oil emulsion composition was obtained.

(Evaluation method) The emulsified compositions were left in constant temperature baths at 50°C, 40°C, and 5°C, and the conditions were observed the next day, 1 week, 2 weeks, and 4 weeks later, and evaluated according to the following criteria.

○: Good with no change in state Δ: Slight separation, occurrence of aggregation X: Separation, occurrence of aggregation clearly No change in status was observed,
It showed good stability over time. In contrast, in the comparative product, separation of the oil agent was observed, especially at high temperatures, and the stability over time was poor.

Further, the water-in-oil emulsion composition of the present invention had a good feeling of use, such as not being oily and blending well into the skin, and the film after application had high water repellency.

Example 2 Face cream (prescription) (%) (1
) Dimethylpolysiloxane (5cs) 12.0
(2) Octamethylcyclotetrasiloxy 15.0 (3) Acrylic-silicone graft 5.0 copolymer (obtained in Reference Example 2) (4) Beeswax 5.0 (
5) White petrolatum 2.0 (6)
) Lanolin 3.0 (
7) Glyceryl trioctanoate 2.0 (8
) Polyoxyalkylene-modified organo 2.0 polysiloxane 0-based surfactant (9) Trisodium phosphate OJα0
1.3-Butylene glycol 7,00 Fragrance Appropriate amount (support) Ultraviolet absorber Appropriate amount ■ Xanthan gum
0.05α purified water
In the general formula (n) with zero remaining amount, G,=62=C)1. .

X = (CL) P mouth (CJ, 0), (CJsO) Jl, a
=2-10, b=1-10. c=20-50. p=3
．． rn=2-10. n=2. RI=H, R2=alkyl group having 16 carbon atoms (manufacturing method) Mix A, components (1) to (8), (b), @, and heat at 75°C.
Dissolve uniformly.

B, component (9), αl) S+13, α◇ are mixed, 75
Dissolve uniformly at ℃.

B was added to C and A to emulsify and cooled to obtain a face cream.

The face cream of the present invention obtained as described above is
It had a very light and good feel when used, was able to form a water-repellent cosmetic film, and had good stability over time.

Example 3 Hand cream (prescription) (%) (1
) Dimethylpolysiloxane (5cs) 12.5
(2) Decamethylcyclopentasiloxa 15. On(3) dimethylpolysiloxane (20cs) 2
．． 5(4) Acrylic-silicone graft 15.
0 copolymer (obtained in Reference Example 2) (5) Dipentaerythritol fatty acid varnish 4.5 chill (6) Lanolin 2.
5(7) Glyceryl trioctanoate 3.0
(8) Polyoxyalkylene modified organo 2.0 Polysiloxane 0 type surfactant (9) Citric acid 0.3
0Q Sodium Citrate 1.2 (1
1)1. 3-Butylene glycol 5.0 (main) Preservative Trace amount 0 Fragrance
Trace amount of α-tocopherol acetate Trace amount (c) Purified water
In the general formula (n) with zero remaining amount, Gl=62=CH3゜X=(Ctl*)p (C, H, mouth), (CsHsO)
, R+, a=2-10, b=1-10. c=2
0-60. p=3. m=2”' 10. n=2.
R, = H, R, = alkyl group having 16 carbon atoms (manufacturing method) ^, components (1) to (8), ①, and α Yu are mixed and dissolved at 70°C.

Mix and dissolve B, r&min (9) to 0, QS) at 70°C.

8 was added to C and A while stirring to emulsify, and the mixture was cooled to obtain a hand cream.

The hand cream of the present invention obtained as described above was able to form a cosmetic film with excellent water repellency, did not feel oily or did not spread easily, and had a good feeling of use. Furthermore, the stability over time was also good.

〔Effect of the invention〕

As detailed above, the water-in-oil emulsion composition of the present invention is
It exhibits excellent stability over time even when using a large amount of silicone oil, has no oiliness or stickiness, has a light texture, and is excellent in forming a highly water-repellent cosmetic film. be.

that's all

Claims (1)

[Scope of Claims] 1. Components (A) to (C) (A) 30 to 60% by weight of an oil containing components (a) and (b) (a) 50 to 95% by weight of a low viscosity silicone oil (b) Acrylic-silicone graft copolymer obtained by radical copolymerization of a dimethylpolysiloxane compound having a radically polymerizable group at one end of its molecular chain and a radically polymerizable monomer mainly composed of acrylate and/or methacrylate. 1 to 50% by weight in oil (B) General formula (I) or (II) ▲Mathematical formula, chemical formula, table, etc.▼(I) [In the formula, G_1 and G_2 may be the same or different, and each CH_3 or (CH_2)_pO(C_2H_4O)_m(C_3H
_6O)_nR_1(p=1-5, m=1-50, n=
Indicates a number from 0 to 30, R_1 is a hydrogen atom or a number of carbon atoms from 1 to
5), X is (CH_2)_p
O(C_2H_4O)_m(C_3H_6O)_nR_
1 (p, m, n and R_1 have the same meanings as above)
, a=5 to 300, and b=0 to 50. However, this excludes the case where both G_1 and G_2 are CH_3 and b=0. ] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) [In the formula, G_1, G_2 and R_2 represents an alkyl group having 2 to 20 carbon atoms. However, this excludes the case where both G_1 and G_2 are CH_3 and b=0. ] A water-in-oil emulsion composition characterized by containing 0.1 to 10% by weight of a polyoxyalkylene-modified organopolysiloxane surfactant represented by (C) 5 to 69.9% by weight of water.