JP2012072085A - Oil-in-water type emulsified cosmetic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil-in-water type emulsified cosmetic, which is stable even at high ethanol concentration of ≤50 mass%, shows good water resistance after the application to the skin or the like, and can effectively hold a water-soluble chemical blended therein.SOLUTION: This oil-in-water type emulsified cosmetic contains: (A) 0.1-10 mass% polyether-denatured silicone having an HLB (Si) of 5-10; (B) 5-50 mass% ethanol; (C) a 0.01-3 mass% hydrophilic thickener; (D) a 0.1-15 mass% polyol; and (E) a water-soluble whitening agent. It is particularly preferable that the oil-in-water type emulsified cosmetic is used as a whitening sunscreen cosmetic which further contains an ultraviolet absorbing agent.

Description

  The present invention relates to an oil-in-water cosmetic that has a fresh feel upon application and exhibits excellent water resistance after application, and has a whitening effect and preferably a sunscreen effect.

  Oil-in-water milks that have been used as a base for external preparations for skin, such as cosmetics, have an excellent feeling of use that gives a fresh feel, but have a drawback that few are satisfactory in terms of water resistance. It was. Therefore, when a water-soluble drug such as tranexamic acid or ascorbic acid is blended, there is a problem that the water-soluble drug is eluted by contact with water after application.

  As an attempt to improve the water resistance of an oil-in-water emulsified cosmetic, for example, Patent Document 1 contains α-monoalkylglyceryl ether, waxes, and silicone oil, and contains silicone oil in the oil phase. Make-up cosmetics comprising an oil-in-water emulsion with improved water resistance by improving the water resistance by incorporating a hydrophobized powder in a specific range is disclosed.

  Patent Document 2 includes an oil-in-water type in which zinc oxide, an acrylic cross-linked copolymer, a nonionic or anionic surfactant having an HLB of 10 or more, water, and silicone oil are blended and zinc oxide is dispersed in the oil phase. An emulsified cosmetic is disclosed and described as having improved storage stability, transparency after use, and water resistance.

On the other hand, the oil-in-water type emulsifying base has a problem that the emulsified particles are destroyed when the alcohol is highly blended, and it is difficult to obtain a sufficiently stable base. , Lower alcohol 50% by weight or more, water, the following general formula as an emulsifier:
(In the above formula, m is 50 to 1000, n is 1 to 40, a is an integer of 5 to 50, and b is an integer of 5 to 50). An alcohol / oil-in-water emulsified composition characterized by substantially not containing other surfactant as an emulsifier is disclosed, and has the effect of giving gloss, softness and moisture to the hair and improving combing. It is described.
However, since the composition described in Patent Document 3 contains a large amount of lower alcohol, application to a general skin care base has been difficult.

JP 2002-308730 A JP 2005-272389 A International Publication No. WO97 / 002888 Pamphlet

  Therefore, the problem in the present invention is that it is stable even when ethanol is highly blended (however, 50% by mass or less), and exhibits excellent water resistance after being applied to the skin and the like, and effectively uses water-soluble drugs such as tranexamic acid. The object is to provide an oil-in-water emulsified cosmetic that can be retained.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have used polyether modified silicone of HLB (Si) 5 to 10 as a surfactant and blended with 5 to 50% by mass of ethanol. Furthermore, the inventors have found that the above-mentioned problems can be solved by blending a specific amount of a hydrophilic thickener and a polyol into an oil-in-water emulsion, thereby completing the present invention.
However, HLB (Si) here is a value obtained by the following calculation formula.

That is, the present invention
(A) 0.1 to 10% by mass of a polyether-modified silicone having 5 to 10 HLB (Si),
(B) 5 to 50% by mass of ethanol,
(C) 0.01-3 mass% hydrophilic thickener,
Provided is an oil-in-water emulsified cosmetic comprising (D) 0.1 to 15% by mass of a polyol and (E) a water-soluble whitening agent.

Since the cosmetic of the present invention is an oil-in-water emulsion containing a large amount of ethanol, a fresh feeling of use can be obtained. On the other hand, after applying to the skin, etc., the phase inverts to a water-in-oil type as the ethanol evaporates, so it exhibits excellent water resistance and effectively holds the formulated water-soluble drug on the skin. Can do.
Furthermore, when an ultraviolet absorber is blended with the cosmetic of the present invention, not only water resistance but also an ultraviolet shielding effect is excellent.

The polyether-modified silicone (component A) in the cosmetic of the present invention is selected from those having an HLB (Si) of 5 to 10, preferably 5 or more, 9 or less, 8 or less, or 7 or less.
In the present invention, a polyether-modified silicone having a molecular weight of 50,000 or more and a hydrophilic group selected from polyoxyethylene (POE) or polyoxypropylene (POP) is preferably used.

In particular, a polyether-modified silicone represented by the following general formula is preferable.
In said formula, m is 50-1000, Preferably it is 150-1000, and n is 1-40. When m is less than 50 and n is less than 1, the emulsion stability is poor, and when m is over 1000 and n is over 40, the resulting composition seems to be sticky. become. Moreover, m: n is preferably 200: 1 to 5: 1, and particularly preferably 60: 1 to 15: 1.
Further, a is 5 to 50, and b is 5 to 50, and the content of these polyoxyalkylene groups in the molecule is not particularly limited, but the content of polyoxyalkylene groups exceeds 20% by weight in the total molecular weight. Things are desirable.

  The polyether-modified silicone used in the present invention may be commercially available, for example, trade name BY11-030 (manufactured by Toray Dow Corning Silicone: 50% by mass of PEG / PPG-19 / 19 dimethicone and 50% by mass). PEG / PPG-19 / 19 dimethicone is a polyether-modified silicone having a molecular weight of 55000 in which m = 400, n = 10, a = 19 and b = 19 in the above general formula; HLB (Si) = 7), trade name BY25-337 (manufactured by Dow Corning Toray, Inc .: 50% by weight PEG / PPG-19 / 19 dimethicone and 50% by weight light liquid isoparaffin (hydrogenated polyisobutene)), Product name KF-6012 (manufactured by Shin-Etsu Silicone: PEG / PPG-20 / 22 butyl ether Dimethicone), the trade name SH3749 (Shin-Etsu Silicone Co., Ltd.: PEG / PPG-20/20 dimethicone), and the like.

  The compounding quantity of the polyether modified silicone (component A) in this invention is 0.1-10 mass%, Preferably it is 0.1-5 mass%, More preferably, it is 0.1-3 mass%. When the blending amount is less than 0.1% by mass, when it exceeds 10% by mass, a stable oil-in-water emulsion may not be obtained.

  The cosmetic of the present invention contains 5% by mass or more of ethanol (component B) as an essential component. The blending amount of ethanol is 5 to 50% by mass, preferably 8 to 50% by mass, and more preferably 8 to 40% by mass. If the blending amount is less than 5% by mass, a stable oil-in-water emulsion may not be obtained.

The cosmetic of the present invention further contains a hydrophilic thickener (component C) as an essential component.
In the present invention, a polyether-modified silicone of HLB (Si) 10 or less (5-10), which has been conventionally used in water-in-oil emulsions, is simply used as a general surfactant for oil-in-water emulsions. It was found that a stable emulsion cannot be obtained only by changing the composition, and a stable oil-in-water emulsion is formed only by blending 5% by mass or more of ethanol and a hydrophilic thickener.

  The hydrophilic thickener used by this invention will not be specifically limited if it is used for cosmetics. Examples thereof include natural water-soluble polymers, semi-synthetic water-soluble polymers, synthetic water-soluble polymers, and inorganic water-soluble polymers.

  Specifically, examples of natural water-soluble polymers include gum arabic, gum tragacanth, galactan, guar gum, carob gum, caraya gum, carrageenan, pectin, agar, quince seed (malmello), alge colloid (gypsum extract), starch (rice, rice, Corn, potato, wheat), plant polymers such as glycyrrhizic acid; microbial polymers such as xanthan gum, dextran, succinoglucan, and bullulan; animal polymers such as collagen, casein, albumin, and gelatin.

  Examples of semi-synthetic water-soluble polymers include starch polymers such as carboxymethyl starch and methylhydroxypropyl starch; methylcellulose, nitrocellulose, ethylcellulose, methylhydroxypropylcellulose, hydroxyethylcellulose, sodium cellulose sulfate, hydroxypropylcellulose, carboxy Examples thereof include cellulose polymers such as sodium methylcellulose (CMC), crystalline cellulose, and cellulose powder; and alginic acid polymers such as sodium alginate and propylene glycol alginate.

  Examples of the synthetic water-soluble polymer include vinyl polymers such as polyvinyl alcohol, polyvinyl methyl ether, polyvinyl pyrrolidone, and carboxyvinyl polymer (carbomer); polyoxyethylene polymers such as polyethylene glycol (molecular weight 1500, 4000, 6000). Molecules; polyoxyethylene polyoxypropylene copolymer copolymer polymer; sodium polyacrylate, polyethyl acrylate, polyacrylamide, acrylic acid / alkyl methacrylate copolymer (trade name “Pemulene TR-1”), etc. Acrylic polymer; polyethyleneimine, cationic polymer and the like. Examples of the inorganic water-soluble polymer include bentonite, AlMg silicate (trade name “Begum”), laponite, hectorite, and silicic anhydride.

  The compounding quantity of the hydrophilic thickener (component C) in the cosmetics of this invention is 0.01-3 mass%, Preferably it is 0.05-3 mass%, More preferably, it is 0.2-1 mass%. . When the blending amount is less than 0.01% by mass, a stable emulsion may not be obtained. When the blending amount exceeds 3% by mass, a heavy touch may be caused during application.

  The cosmetic of the present invention further contains a polyol (component D) as an essential component. By adding a polyol, the transparency and stability of the oil-in-water emulsion can be further improved. For example, by adding a polyol, stability is maintained even if the amount of alcohol to be blended is reduced, and the alcohol odor of the resulting preparation can be suppressed.

  Although the polyol used by this invention will not be specifically limited if it is normally used for cosmetics, For example, dynamite glycerol, 1, 3- butylene glycol, dipropylene glycol, propylene glycol etc. can be mentioned. In particular, 1,3-butylene glycol improves stability most effectively.

  The compounding quantity of the polyol (component (D)) in the cosmetics of this invention is 0.1-15 mass%, Preferably it is 1-10 mass%, More preferably, it is 3-7 mass%. When the blending amount is less than 1% by mass, a stable emulsion may not be obtained. When the blending amount exceeds 15% by mass, a heavy touch may be caused during application.

Furthermore, the cosmetic of the present invention contains a water-soluble drug, particularly a water-soluble whitening agent (component (E)).
The water-soluble whitening agent used in the present invention may be those conventionally used for external preparations for skin such as cosmetics, and is not particularly limited. For example, ascorbic acid or a derivative thereof, specifically, sodium L-ascorbate , L-ascorbic acid ester magnesium salt, L-ascorbic acid glucoside, 2-O-ethyl-L-ascorbic acid, 3-O-ethyl-L-ascorbic acid, tranexamic acid, arbutin, 4-methoxysalicylate, specifically Examples thereof include 4-methoxysalicylic acid sodium salt, 4-methoxysalicylic acid potassium salt, and the like.

  The compounding quantity of the water-soluble whitening agent (component (E)) in the cosmetics of this invention is 0.01-3 mass%, Preferably it is 0.1-3 mass%. When the blending amount is less than 0.01% by mass, a sufficient whitening effect may not be obtained. When the blending amount exceeds 3% by mass, it may crystallize and precipitate and a sufficient whitening effect may not be obtained.

  As described above, the cosmetic of the present invention is an oil-in-water emulsion having a fresh feel at the time of application, but after application, the phase is reversed and the water resistance is improved. Effectively held and effective. Therefore, it goes without saying that the same effect can be obtained when a water-soluble drug other than the whitening agent is blended.

  The cosmetic of the present invention can be produced according to a method conventionally used for producing an emulsion. For example, an oil phase-forming component is mixed, and an oil component is added to an aqueous phase component containing ethanol (component B), a hydrophilic thickener (component C), a polyol (component D), and a water-soluble whitening agent (component E). The cosmetic of the present invention can be obtained by adding an oil phase mixed with polyether modified silicone (component A) of HLB (Si) 5 to 10 to the aqueous phase while stirring with a homomixer or the like. .

The cosmetic of the present invention has a feature that it is fresh and fresh when used, and forms a film with excellent water resistance after application. Therefore, the cosmetic of the present invention is suitable for providing as a skin care cosmetic and a makeup cosmetic.
For example, when an oil-soluble ultraviolet absorber is blended with the cosmetic of the present invention, a fresh and refreshing feel is obtained when applied to the skin, and a water-resistant film is formed on the skin after application. In addition to the effect, certain UV protection is maintained. In addition, when used as a makeup cosmetic, good cosmetic durability based on excellent water resistance can be secured.

Therefore, the present invention provides an oil-in-water cosmetic, particularly a sunscreen cosmetic, further containing an ultraviolet absorber.
The ultraviolet absorber blended in the emulsified cosmetic of the present invention is not limited to oil solubility and water solubility, and is not particularly limited as long as it is usually used in cosmetics.
For example, methoxycinnamic acid derivatives, diphenylacrylic acid derivatives, salicylic acid derivatives, paraaminobenzoic acid derivatives, triazine derivatives, benzophenone derivatives, benzalmalonate derivatives, anthranyl derivatives, imidazoline derivatives, 4,4-diarylbutadiene derivatives, and phenylbenz Examples include imidazole derivative systems. Specifically, 2-ethylhexyl paramethoxycinnamate, homosalate, octyl salicylate, oxybenzone, 4-t-butyl-4′-methoxydibenzoylmethane, octyl triazone, bisethylhexylphenol methoxyphenyl triazine, methylene bisbenzotria Zolyltetramethylbutylphenol, 2-hydroxy-4-methoxybenzophenone, dihydroxydimethoxybenzophenone, dihydroxybenzophenone, tetrahydroxybenzophenone, diethylaminohydroxybenzoyl hexyl benzoate, 2-cyano-3,3-diphenylacrylic acid-2'-ethylhexyl ester Polysilicone-15, drometrizole polysiloxane, phenylbenzimidazole sulfonic acid and the like. One or two or more of these can be appropriately selected and used as necessary.

  The compounding quantity of the ultraviolet absorber mix | blended with the oil-in-water type sunscreen cosmetics of this invention is 0.1-35 mass%, Preferably it is 1-30 mass%, More preferably, you may be 5-25 mass%.

  The emulsified cosmetic of the present invention contains other components conventionally used in cosmetics in addition to the above essential components A to E and / or UV absorbers as long as the effects of the present invention are not impaired. May be. Specific examples include humectants, oils, buffers, chelating agents, preservatives, and the like.

  Hereinafter, the present invention will be described in more detail with specific examples, but the present invention is not limited to the following examples. Moreover, the compounding quantity in a following example etc. shows the mass% unless there is particular notice.

(Examples 1-4 and Comparative Example 1)
Oil-in-water emulsion compositions were prepared with the compositions listed in Tables 1 and 2 below. Next, the water resistance of each sample was evaluated by the remaining degree of the water-soluble whitening agent (tranexamic acid) blended in each composition after being bathed in water. The measurement method and evaluation method are as follows.
-Measuring method of main ingredient residual degree (1) 50 mg of each sample is apply | coated to the plate (5 cm x 5 cm) made from PMMA.
(2) Dry for 15 minutes.
(3) The plate is immersed in ion-exchanged water in a 500 ml beaker to elute the water-soluble components in the sample.
(4) Collect ion-exchanged water in the beaker.

-Evaluation method of whitening agent residual degree The ion-exchange water collect | recovered by the said measuring method (4) is applied to HPLC, and tranexamic acid is quantified. The HPLC conditions are as follows.
Separation tube: CAPCELL PAK C18 MG-II S-3
Separation tube temperature: 40 ° C
Eluent: 0.2% phosphoric acid solution 5% methanol Injection volume: 5 μL
Detector: 210nm
Under the above conditions, the peak area of tranexamic acid was obtained from the HPLC chart, the amount of tranexamic acid eluted in ion-exchanged water was calculated, and the residual degree of tranexamic acid (whitening agent) remaining on the plate without elution was evaluated. . The results are also shown.
○: Remaining whitening agent is 90% or more ×: Remaining whitening agent is less than 90%

  From the results shown in Tables 1 and 2, in the oil-in-water emulsion compositions (Examples 1 to 4) prepared using the components A to D in the present invention and further containing the main component (component E), after application, However, in Comparative Example 1 in which the polyether-modified silicone having the predetermined HLB (Si) was not used, the main agent was easily dissolved in water. It was found that it eluted.

(Reference Example 1 and Comparative Examples 2 to 5)
An oil-in-water emulsion composition (Reference Example 1) having a composition (not including tranexamic acid) similar to Example 1 (including a polyether-modified silicone of HLB (Si) = 7) and the polyether-modified silicone An attempt was made to prepare compositions (Comparative Examples 2 to 5) substituted with a silicone-based active agent having HLB (Si) not included in the predetermined range of the present application (see Table 3).

  When the emulsification experiment was tried about the composition of the reference example 1 and the comparative examples 2-5, in the comparative examples 2-4 using the polyether modified silicone whose HLB (Si) is less than 5, the oil-in-water type excellent in stability. An emulsion could not be obtained (emulsification stability: x). On the other hand, in Reference Example 1 and Comparative Example 5 using polyoxyethylene (20) polyoxypropylene (8) cetyl ether, which is a representative O / W activator having an HLB (Si) of 10 or more, the stability is excellent. An oil-in-water emulsion was obtained (emulsification stability: ◯).

Subsequently, the ultraviolet shielding effect comparison of the reference example 1 and the comparative example 5 and the comparative experiment of the water resistance effect of the ultraviolet shielding effect were conducted. In the comparative experiment of the ultraviolet shielding effect, each sample of 0.75 mg / cm ² was uniformly applied to a PMMA (polymethyl methacrylate) plate having a rough surface, and the absorbance was measured with a spectrophotometer (U-4100 Hitachi, Ltd.). It was measured. In addition, in the comparative experiment of the water resistance effect, each sample was applied to the PMMA plate described above, the absorbance was measured, exposed to strong water for 15 minutes, sufficiently dried, then the absorbance was measured again, and methoxycinnamic acid was measured. The percent change in the maximum absorbance of ethylhexyl was calculated.
As a result, surprisingly, Reference Example 1 shows a higher ultraviolet shielding effect than Comparative Example 5 having the same absorbent composition (absorbance values at a wavelength of 310 nm are shown in Table 3), and also has a very high water resistance effect. (The change rate in absorbance was about 15% smaller in Reference Example 1 than in Comparative Example 5).

  The oil-in-water emulsified cosmetic composition of the present invention has a fresh feeling of use characteristic of an oil-in-water emulsion at the time of application, and after application, the phase is changed to a water-in-oil type and exhibits excellent water resistance. Therefore, the outflow of the water-soluble whitening agent is suppressed, the whitening effect is maintained for a long time, and it can be used as a skin external preparation that achieves both usability and water resistance. Moreover, if an ultraviolet absorber is mix | blended, the reliable ultraviolet protection excellent in water resistance will be obtained.

The present inventors, as a result of intensive studies to solve the above problems, the polyether-modified silicone HLB (Si) 5~ 8 used as a surfactant were blended the following ethanol 5 to 50 mass% Furthermore, the inventors have found that the above-mentioned problems can be solved by blending a specific amount of a hydrophilic thickener and a polyol into an oil-in-water emulsion, thereby completing the present invention.
However, HLB (Si) here is a value obtained by the following calculation formula.

That is, the present invention
(A) 0.1 to 10% by mass of a polyether-modified silicone having 5 to 8 HLB (Si),
(B) 5 to 50% by mass of ethanol,
(C) 0.01-3 mass% hydrophilic thickener,
Provided is an oil-in-water emulsified cosmetic comprising (D) 0.1 to 15% by mass of a polyol and (E) a water-soluble whitening agent.

Polyether-modified silicone in the cosmetic of the present invention (component A), the HLB (Si) is selected from those of 5-8.
In the present invention, a polyether-modified silicone having a molecular weight of 50,000 or more and a hydrophilic group selected from polyoxyethylene (POE) or polyoxypropylene (POP) is preferably used.

The cosmetic of the present invention can be produced according to a method conventionally used for producing an emulsion. For example, an oil phase-forming component is mixed, and an oil component is added to an aqueous phase component containing ethanol (component B), a hydrophilic thickener (component C), a polyol (component D), and a water-soluble whitening agent (component E). The cosmetic of the present invention can be obtained by adding an oil phase mixed with polyether modified silicone (component A) of HLB (Si) 5 to 8 to the aqueous phase while stirring with a homomixer or the like. .

(Reference Example 1 and Comparative Examples 2 to 5)
An oil-in-water emulsion composition (Reference Example 1) having a composition (not including tranexamic acid) similar to Example 1 (including a polyether-modified silicone of HLB (Si) = 7.7 ) and its polyether modification An attempt was made to prepare a composition (Comparative Examples 2 to 5) in which silicone was replaced with a silicone-based active agent having HLB (Si) not included in the predetermined range of the present application (see Table 3).

Claims (5)

(A) 0.1 to 10% by mass of a polyether-modified silicone having 5 to 10 HLB (Si),
(B) 5 to 50% by mass or less of ethanol,
(C) 0.01-3 mass% hydrophilic thickener,
(D) 0.1-15 mass% or more polyol and (E) water-soluble whitening agent are contained, The oil-in-water type emulsion cosmetic characterized by the above-mentioned. The polyether-modified silicone is a polyether-modified silicone having a molecular weight of 50,000 or more and a hydrophilic group selected from polyoxyethylene (POE) or polyoxypropylene (POP). Cosmetics described. The polyether-modified silicone has the following formula:
(Wherein m is 50 to 1000, n is 1 to 40, a is an integer of 5 to 50, and b is an integer of 5 to 50). Item 3. A cosmetic according to Item 2. The cosmetic according to any one of claims 1 to 3, further comprising an ultraviolet absorber in an amount of 0.1 to 35% by mass and used for sunscreen. The said water-soluble whitening agent is 1 type (s) or 2 or more types selected from ascorbic acid and its derivative (s), tranexamic acid, arbutin, and 4-methoxy salicylate, The method as described in any one of Claim 1 to 4 Cosmetics.