Water-in-oil type emulsion cosmetic

Abstract

The purpose of the present invention is to provide a water-in-oil type cosmetic which ensures emulsion stability in the case where a volatile hydrocarbon oil component is added, has excellent texture such as not leaving a greasy feeling, and is highly compatible with the skin. The present invention relates to a water-in-oil type emulsified cosmetic comprising: (A) 20 to 30 mass % of an oil component; (B) a fatty acid ester having an HLB of 5 to 10; (C) a nonionic surfactant having an HLB of 1 to 4; (D) an organic modified clay mineral; and (E) water, wherein volatile hydrocarbon oil accounts for 10 mass % or more of the oil component (A) and silicone oil is not contained.

Claims

1. A water-in-oil type emulsified cosmetic consisting essentially of: (A) 20 to 30 mass % of an oil component, the oil component comprising: (i) at least 10 mass % or more with respect to the oil component of a volatile hydrocarbon oil, and (ii) no silicone oil; (B) at least one fatty acid ester selected from the group consisting of PEG-8 diisostearate, PEG-12 diisostearate, PEG-8 dioleate, and PEG-10 glyceryl triisostearate; (C) 0.1 to 3 mass % of at least one nonionic surfactant selected from the group consisting of glyceryl diisostearate, PEG-4 sorbitan triisostearate, PEG-9 polydimethylsiloxyethyl dimethicone and lauryl PEG-9 polydimethylsiloxy dimethicone; (D) an organic modified clay mineral; and (E) water, wherein said volatile hydrocarbon oil is selected from the group consisting of isododecane, isohexadecane, hydrogenated polyisobutene and mixtures thereof.

2. The cosmetic according to claim 1, wherein said 20 to 30 mass % of an oil component comprises 20% or more by mass of said volatile hydrocarbon oil.

3. The cosmetic according to claim 1, wherein the water is present at 55.2 to 78.8 mass % relative to the total mass of the cosmetic.

4. The cosmetic according to claim 3, wherein said 20 to 30 mass % of an oil component comprises 20% or more by mass of said volatile hydrocarbon oil.

Description

DESCRIPTION OF EMBODIMENTS

(1) An emulsified cosmetic of the present invention contains an oil component (component A) as an essential component. The oil component used in the present invention is not particularly limited insofar as the oil component is a liquid oil component which has heretofore been used for a cosmetic and the like and may appropriately be selected from among natural or synthetic hydrocarbon oil, higher fatty acids, higher alcohols, ester oil, and the like to be used. However, from the viewpoint of improvement in compatibility with the skin, the emulsified cosmetic of the present invention does not contain silicone oil.

(2) A content of the oil component in the cosmetic of the present invention may be 20 to 30 mass %. Further, the present invention is characterized in that a volatile hydrocarbon oil component accounts for 10 mass % or more of the oil component, more preferably 20 mass % or more of the oil component. High compatibility with the skin is attained in the cosmetic of the present invention by incorporating the volatile oil component in the above-specified predetermined amount or more.

(3) The volatile hydrocarbon oil component to be incorporated into the cosmetic of the present invention is not particularly limited insofar as the volatile hydrocarbon oil component is hydrocarbon oil which has heretofore been used for a cosmetic and the like and has volatility at a room temperature, and examples thereof include isododecane, isohexadecane, hydrogenated polyisobutene, and the like.

(4) The emulsified cosmetic of the present invention contains a fatty acid ester (component B) having an HLB of 5 to 10. The fatty acid ester (HLB=5 to 10) to be used in the present invention may be one kind or two or more kinds appropriately selected from among those ordinarily used for a cosmetic and the like.

(5) Specific examples thereof include the following.

(6) Polyglycerin fatty acid ester such as hexaglyceryl monostearate (HLB 9.0), hexaglyceryl monooleate (HLB 9.0), decaglyceryl distearate (HLB 9.5), and decaglyceryl diisostearate (HLB 10.0). Polyoxyethylene glycerin fatty acid ester such as polyoxyethylene (hereinafter abbreviated to POE) (5) glyceryl monostearate (HLB 9.5), and POE (5) glyceryl monooleate (HLB 9.5). Polyoxyethylene sorbitan fatty acid ester such as POE (6) sorbitan monostearate (HLB 9.5) and POE (6) sorbitan monooleate (HLB 10.0). Polyethylene glycol fatty acid ester such as PEG-8 diisostearate (HLB 6.0), PEG-12 diisostearate (HLB 8.0), PEG-8 isostearate (HLB 10.0), and PEG-8 dioleate (HLB 8.0). Polyoxyethylene glyceryl isostearate such as PEG-10 glyceryl triisostearate (HLB 5.0), PEG-8 glyceryl isostearate (HLB 10.0), and PEG-10 glyceryl isostearate (HLB 10.0).

(7) A content of the fatty acid ester having HLB of 5 to 10 (component B) in the cosmetic of the present invention may be 0.01 to 2 mass %, preferably 0.01 to 1 mass %. The long-term stability of a preparation is deteriorated when the content is less than 0.1 mass %, and it is difficult to obtain a preparation as a water-in-oil emulsion when the content exceeds 2 mass % because the emulsifiability becomes worse.

(8) The emulsified cosmetic of the present invention contains a nonionic surfactant having HLB of 1 to 4 (component C). The nonionic surfactant (HLB=1 to 4) to be used in the present invention may be one kind or two or more kinds appropriately selected from among those ordinarily used for a cosmetic and the like.

(9) For example, examples of a hydrocarbon-based surfactant include glyceryl diisostearate (HLB 3.0), PEG-4 sorbitan triisostearate (HLB 3.0), POE (2) stearyl ether (HLB 4.0), self-emulsification type propylene glycol monostearate (HLB 4.0), glyceryl myristate (HLB 3.5), glyceryl monostearate (HLB 4.0), self-emulsification type glyceryl monostearate (HLB 4.0), glyceryl monoisostearate (HLB 4.0), glyceryl monooleate (HLB 2.5), hexaglyceryl tristearate (HLB 2.5), decaglyceryl pentastearate (HLB 3.5), decaglyceryl pentaisostearate (HLB 3.5), decaglycerylpentaoleate (HLB 3.5), sorbitan tristearate (HLB 2.1), POE (6) sorbitol hexastearate (HLB 3.0), POE (3) castor oil (HLB 3.0), PEG (2) monostearate (HLB 4.0), ethylene glycol monostearate (HLB 3.5), and the like.

(10) Examples of a silicone-based surfactant include PEG-9 polydimethylsiloxyethyl dimethicone (HLB 3.8), lauryl PEG-9 polydimethylsiloxy dimethicone (HLB 2.8), and the like. For example, a polyoxyethylene polydimethylsiloxyethyl dimethicone copolymer (also described as PEG-9 polydimethylsiloxyethyl dimethicone) described as polyoxyalkylene-modified organopolysiloxane in Patent Document 3 is commercially available as Silicone KF-6028 (manufactured by Shin-Etsu Chemical Co., Ltd.), and the commercially available product may also be used.

(11) A content of the nonionic surfactant having HLB of 1 to 4 in the cosmetic of the present invention may be 0.1 to 5 mass %, preferably 0.1 to 3 mass %. It is difficult to attain the excellent emulsion stability when the content is less than 0.1 mass %, while texture is deteriorated in some cases when the content exceeds 5 mass %.

(12) The organic modified clay mineral (component D) to be incorporated into the emulsified cosmetic of the present invention is used as a coemulsifier and it is preferable to use those obtained by modifying a clay mineral with a quaternary ammonium salt type cationic surfactant, wherein the clay mineral is one kind of colloidal water-containing aluminum silicate having a three-layer structure and generally represented by the following formula:
(X,Y).sub.2-3(Si,Al).sub.4O.sub.10(OH).sub.2Z.sub.1/3.Math.nH.sub.2O[Chemical formula 1]

(13) (wherein XAl, Fe(III), Mn(III), or Cr(III); YMg, Fe(II), Ni, Zn, or Li; ZK, Na, or Ca).

(14) Specifically, the organic modified clay mineral is obtainable by treating the clay mineral such as natural or synthetic (in this case, the (OH) group in the formula is substituted by fluorine) montmorillonites including montmorillonite, saponite, hectorite, and the like (examples of a commercialized product thereof include Veegum, Kunipia, Laponite, and the like) and synthetic mica known as sodium silicic mica, sodium or lithium taeniolite (examples of a commercialized product thereof include Dimonite manufactured by Topy Industries, Limited) with the quaternary ammonium salt type cationic surfactant.

(15) The quaternary ammonium salt type cationic surfactant used herein is represented by the following general formula:

(16) ##STR00001##

(17) (wherein R.sup.1 represents an alkyl group or a benzyl group having 10 to 22 carbon atoms; R.sup.2 represents a methyl group or an alkyl group having 10 to 22 carbon atoms; each of R.sup.3 and R.sup.4 is an alkyl group or a hydroxylalkyl group having 1 to 3 carbon atoms; and X represents a halogen atom or a methyl sulfate residue).

(18) Examples of the quaternary ammonium salt type cationic surfactant include dodecyltrimethylammonium chloride, myristyltrimethylammonium chloride, cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, arachyltrimethylammonium chloride, behenyltrimethylammonium chloride, myristyldimethylethylammonium chloride, cetyldimethylethylammonium chloride, stearyldimethylethylammonium chloride, arachyldimethylethylammonium chloride, behenyldimethylethylammonium chloride, myristyldiethylmethylammonium chloride, cetyldiethylmethylammonium chloride, stearyldiethylmethylammonium chloride, arachyldiethylmethylammonium chloride, behenyldiethylmethylammonium chloride, benzyldimethylmyristylammonium chloride, benzyldimethylcetylammonium chloride, benzyldimethylstearylammonium chloride, benzyldimethylbehenylammonium chloride, benzylmethylethylcetylammonium chloride, benzylmethylethylstearylammonium chloride, dibehenyldihydroxyethylammonium chloride, and corresponding bromides and the like, and further dipalmitylpropylethylammonium methylsulfate, and the like. When carrying out the present invention, one kind or two or more kinds of the above are arbitrarily selected.

(19) Typical examples of the organic modified clay mineral include dimethyldistearylammonium hectorite, benzyldimethylstearylammonium hectorite, distearyldimethylammonium chloride-treated aluminum magnesium silicate, and the like. Examples of commercialized products thereof include Bentone 27 (benzyldimethylstearylammonium hectorite manufactured by Elementis Specialties) and Bentone 38 (distearyldimethylammonium chloride-treated hectorite manufactured by Elementis Specialties).

(20) A content of the organic modified clay mineral (component D) in the cosmetic of the present invention may be 1 to 20 mass %, preferably 1 to 10 mass %. It is difficult to attain the excellent emulsion stability and favorable viscosity when the content is less than 1 mass %, while there is a tendency that mealy feeling occurs when the content exceeds 20 mass %.

(21) The emulsified cosmetic of the present invention contains the above-described components A to D and water (component E) as essential components, and other components which are ordinarily incorporated into skin cosmetics may be incorporated within a range which does not inhibit the effect of the present invention. More specifically, a powder, a lipid soluble UV absorber, a water soluble UV absorber, a sequestering agent, a neutralizer, a pH adjuster, an antioxidant, an antibacterial agent, various drugs, various extracts, and the like may be included.

(22) The skin cosmetic of the present invention is capable of eliminating the greasy feeling and of imparting high compatibility with the skin and a moist feeling owing to the incorporation of the volatile hydrocarbon. Further, the skin cosmetic is excellent in emulsion stability owing to the combination of the surfactants (components B and C) each having the predetermined HLB. Therefore, the skin cosmetic is suitably used as a skin cosmetic for the usages for which water-in-oil type emulsions have heretofore been used.

Examples

(23) The present invention will hereinafter be described in more details in conjunction with examples, but the present invention is not limited to the following Examples. Further, each of contents in the following Examples and the like indicates mass % unless otherwise noted.

(24) Water-in-oil type emulsion compositions (Examples) of the present invention and compositions of Comparative Examples were prepared and evaluated on the following items.

(25) 1. Emulsion Particle Stability

(26) The emulsion was frozen and then evaluated by visual observation.

(27) : Emulsion particles were uniformly dispersed.

(28) X: Particle coalescence was observed.

(29) 2. Appearance Stability

(30) An appearance of the prepared emulsion after being left to stand for 4 weeks at a room temperature was evaluated.

(31) : Separation was observed.

(32) X: Stable without separation.

(33) 3. Compatibility with the Skin

(34) Each of the prepared samples was used by female panel of experts (N=7) for evaluation of compatibility with the skin.

(35) : 6 or more panelists rated high compatibility with the skin.

(36) : 4 to 5 panelists rated high compatibility with the skin.

(37) X: 3 or less panelists rated high compatibility with the skin.

(38) Samples of the compositions listed in the following Tables I to 4 were prepared and evaluated on the same items. Results of the evaluation are also shown in the Tables.

(39) TABLE-US-00001 TABLE 1 Comparative Example 1 Example 1 Water Balance Balance Glycerin 13 13 1,3-butylene glycol 2 2 Dimethyldistearylammonium hectorite 2.0 2.0 PEG-9 polydimethylsiloxyethyl 1.3 1.3 dimethicone (HLB = 3.8) PEG-8 diisostearate (HLB = 6) 0.5 0.5 Liquid paraffin 2.5 2.5 Isohexadecane 9 Isododecane 8 Vaseline 1 1 Dimethicone 17 Cetyl ethylhexanoate 5 5 Phenoxyethanol 0.5 0.5 Compatibility with the skin X Emulsion particle stability Appearance stability

(40) Example 1 in which the silicone oil component (dimethicone) used in Comparative Example 1 was replaced by the volatile hydrocarbon oil (isohexadecane and isododecane) was free from the unsatisfactory compatibility with the skin observed in Comparative Example 1 and attained high compatibility with the skin.

(41) TABLE-US-00002 TABLE 2 Comparative Comparative Example 2 Example 3 Example 2 Example 3 Example 4 Example 5 Example 6 Water Balance Balance Balance Balance Balance Balance Balance Glycerin 13 13 13 13 13 13 13 1,3-butylene glycol 2 2 2 2 2 2 2 Dimethyldistearylammonium 2.0 2.0 2.0 2.0 2.0 2.0 2.0 hectorite PEG-9 polydimethylsiloxyethyl 2.1 1.3 1.3 1.3 1.3 1.3 dimethicone (HLB = 3.8) PEG-8 diisostearate (HLB = 6) 1 0.5 PEG-12 diisostearate (HLB = 8) 0.5 PEG-8 isostearate (HLB = 10) 0.5 PEG-8 dioleate (HLB = 6) 0.5 PEG-10 glyceryl triisostearate 0.5 (HLB = 5) Liquid paraffin 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Isohexadecane 9 9 9 9 9 9 9 Isododecane 8 8 8 8 8 8 8 Vaseline 1 1 1 1 1 1 1 Cetyl ethylhexanoate 5 5 5 5 5 5 5 Phenoxyethanol 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Compatibility with the skin () () Emulsion particle stability X X Appearance stability X X

(42) TABLE-US-00003 TABLE 3 Example 7 Example 8 Example 9 Ion exchange water Balance Balance Balance Glycerin 13 13 13 1,3-butylene glycol 2 2 2 Dimethyldistearylammonium 2.0 2.0 2.0 hectorite PEG-8 diisostearate (HLB = 6) 0.5 0.5 0.5 Diglyceryl diisostearate (HLB = 3) 1.3 PEG-4 sorbitan triisostearate 1.3 (HLB = 3) Lauryl PEG-9 polydimethylsiloxy 1.3 dimethicone (HLB = 2.8) Liquid paraffin 2.5 2.5 2.5 Isohexadecane 13 13 13 Isododecane 10 10 10 Phenoxyethanol 0.5 0.5 0.5 Compatibility with the skin Emulsion particle stability Appearance stability

(43) TABLE-US-00004 TABLE 4 Example Example Example Example Example Example 10 11 12 13 14 15 Water Balance Balance Balance Balance Balance Balance Glycerin 13 13 13 13 13 13 1,3-butylene glycol 2 2 2 2 2 2 Dimethyldistearylammonium 2.0 2.0 2.0 2.0 2.0 2.0 hectorite PEG-9 polydimethylsiloxyethyl 0.8 1.5 2 3 1.5 1.5 dimethicone (HLB = 3.8) PEG-8 diisostearate (HLB = 6) 0.5 0.5 0.5 0.5 0.2 0.6 Liquid paraffin 2.5 2.5 2.5 2.5 2.5 2.5 Isohexadecane 9 9 9 9 9 9 Isododecane 8 8 8 8 8 8 Vaseline 1 1 1 1 1 1 Cetyl ethylhexanoate 5 5 5 5 5 5 Phenoxyethanol 0.5 0.5 0.5 0.5 0.5 0.5 Compatibility with the skin Emulsion particle stability Appearance stability

(44) Comparative Examples 2 and 3 which lacks either one of the fatty acid ester having HLB of 5 to 10 (Component B) and the nonionic surfactant having HLB of 1 to 4 (Component C) failed to give a stable emulsion, and, therefore, it was impossible to evaluate the texture. In contrast, in the case where the HLB value was varied within the predetermined range by variously replacing the component B or the component C (Examples 2 to 9) and in the case where the contents of the components B and C were varied (Examples 10 to 15), it was proved that stable water-in-oil emulsions were prepared and that cosmetics having high compatibility with the skin were able to be obtained.

(45) (Formulation 1)

(46) TABLE-US-00005 Skin Cream Components Content (mass %) (1) Isododecane 5 (2) Isohexadecane 4 (3) Mineral oil 5 (4) Cetyl ethylhexanoate 10 (5) Dimethyldistearylammonium hectorite 2 (6) PEG-8 diisostearate (HLB = 6) 0.5 (7) Diglyceryl diisostearate (HLB = 3) 1.3 (8) Glycerin 13 (9) 1,3-butylene glycol 2 (10) Phenoxyethanol 0.5 (11) Water balance

(47) Production Method: (1) to (7) were homogeneously mixed and dissolved at a room temperature (oil phase). Meanwhile, (8) to (11) were homogeneously mixed and dissolved at a room temperature (water phase). The oil phase was added to the water phase, and the mixture was emulsified by using a homo mixer to obtain a desired skin cream.

(48) (Formulation 2)

(49) TABLE-US-00006 Skin Care Cream Components Content (mass %) (1) Isododecane 5 (2) Isohexadecane 10 (3) Vaseline 2.5 (4) Mineral oil 5 (5) Dimethyldistearylammonium hectorite 2 (6) PEG-8 dioleate (HLB = 6) 0.5 (7) PEG-9 polydimethylsiloxyethyl dimethicone 1.3 (HLB = 3.8) (8) Glycerin 13 (9) 1,3-butylene glycol 2 (10) Tranexamic acid 2 (11) Vitamin E acetate 0.5 (12) Potassium 4-methoxysalicylate 1 (13) Phenoxyethanol 0.5 (14) Water balance

(50) Production Method: (1) to (7) were heated to 50 C. and homogeneously mixed and dissolved (oil phase). Meanwhile, (8) to (14) were homogeneously mixed and dissolved at a room temperature (water phase). The oil phase was added to the water phase, and the mixture was emulsified by using a homo mixer to obtain a desired skin care cream.

(51) (Formulation 3)

(52) TABLE-US-00007 Sun Care Cream Components Content (mass %) (1) Isododecane 8 (2) Isohexadecane 9 (3) Octylmethoxy cinnamate 6 (4) Octocrylene 5 (5) Dimethyldistearylammonium hectorite 2 (6) PEG-8 diisostearate (HLB = 6) 0.5 (7) PEG-4 sorbitan triisostearate (HLB = 3) 1.3 (8) Glycerin 13 (9) 1,3-butylene glycol 2 (10) Phenoxyethanol 0.5 (11) Water balance

(53) Production Method: (1) to (7) were homogeneously mixed and dissolved at a room temperature (oil phase). Meanwhile, (8) to (11) were homogeneously mixed and dissolved at a room temperature (water phase). The oil phase was added to the water phase, and the mixture was emulsified by using a homo mixer to obtain a desired sun care cream.