JP5058353B2 - Oil-in-water emulsion composition - Google Patents

Description

  The present invention relates to an oil-in-water emulsion composition that has a fresh feel at the time of application, is excellent in water resistance after application, and has an oil-soluble ultraviolet absorber blended in an outer phase (water phase) and has a stable and high UV protection ability. .

  Sunscreen cosmetics are intended to protect the skin from the harmful effects of ultraviolet rays by cutting the ultraviolet rays in the sun. Examples of the base include emulsification type, lotion type, oil type, etc. Among them, the oil-in-water emulsification type has a fresh feeling of use and can be formulated from low SPF to high SPF products. Widely used (Non-Patent Document 1).

  However, the oil-in-water emulsion is excellent in the feeling of use that gives a fresh feeling, but has a drawback that few of the water-resistant emulsions are satisfactory.

Furthermore, the oil-in-water type emulsifying base has a problem that when the alcohol is highly blended, the emulsified particles are destroyed, 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 1 contains a large amount of lower alcohol, it has been difficult to apply it to a general skin care base. Moreover, although the ultraviolet-ray scattering agent may be mix | blended in order to improve the ultraviolet-ray protective ability (SPF, PFA) in the formulation which mix | blended ethanol highly, the usability may be squeezed by it.

  In addition, many oil-soluble UV absorbers are hardly soluble, and in order to dissolve them, it is necessary to add a large amount of highly polar oil, resulting in the loss of the fresh feeling of use unique to oil-in-water emulsions. There may be a problem of stability such that the UV absorber is precipitated at a low temperature in the phase.

International Publication No. WO97 / 002888 Pamphlet

“New Cosmetics 2nd Edition” Takeo Mitsui, Nanzan-do, 2001, pp. 497-504

  Therefore, the problem in the present invention is an oil-in-water emulsion composition which 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, etc. It is an object to provide an oil-in-water emulsified composition containing an oil-soluble ultraviolet absorber having a low viscosity and excellent in feeling of use and ultraviolet protective ability.

In order to solve such problems, the present inventors have conducted extensive research, and as a result, HLB (Si) 5 to 10 polyether-modified silicone is used as a surfactant, and 5 to 50% by mass of ethanol is blended. Furthermore, by blending a specific amount of a hydrophilic thickener and a polyol into an oil-in-water emulsion, the above problem can be solved by blending an aqueous dispersion of an oil-soluble UV absorber in the aqueous phase. The headline and the present invention were completed.
However, HLB (Si) here is a value obtained by the following calculation formula.

That is, the present invention
(A) containing an aqueous dispersion of an oil-soluble ultraviolet absorber in an aqueous phase (outer phase);
(B) 0.1 to 10% by mass of a polyether-modified silicone having 5 to 10 HLB (Si),
(C) 5-50% by weight of ethanol,
An oil-in-water emulsion composition comprising (d) 0.01 to 3% by mass of a hydrophilic thickener and (e) 0.1 to 15% by mass of a polyol is provided.

Since the emulsion composition 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 application to the skin or the like, the phase is changed to a water-in-oil type as the ethanol evaporates, so that excellent water resistance can be exhibited.
Furthermore, the oil-in-water emulsified composition of the present invention was able to improve the stability of the system by blending an ultraviolet absorber that is sparingly soluble in oil into the aqueous phase (outer phase). Further, there is an advantageous effect that the ultraviolet protection ability is improved as compared with the case where the same ultraviolet absorber is blended in the oil phase (inner phase). Therefore, the oil-in-water emulsified composition of the present invention is particularly suitable for use as a sunscreen cosmetic having a fresh feeling of use and excellent UV protection.

It is a graph which shows the ultraviolet absorption spectrum of the composition of Example 1 and Comparative Example 1.

The oil-in-water emulsion composition of the present invention is characterized by containing an aqueous dispersion (component a) of an oil-soluble ultraviolet absorber in an aqueous phase (outer phase).
The oil-soluble UV absorber is not particularly limited, but is preferably selected from UV absorbers that are insoluble in water and hardly soluble in oil. However, substantially insoluble oils such as methylenebisbenzotriazole tetramethylbutylphenol are not included. When an oil-in-water emulsion composition is prepared using an aqueous dispersion of an oil-insoluble ultraviolet absorber and applied to the skin, the applied skin may become unnaturally whitish.
Examples of the poorly soluble ultraviolet absorber include those described in, for example, JP-A-2009-91307, and specific examples include benzophenone derivatives and triazine derivatives. 4-bis-{[4- (2-ethylhexyloxy) -2-hydroxy] phenyl} -6- (4-methoxyphenyl)-(1,3,5) -triazine (hereinafter referred to as “bisethylhexyl” in this specification). Oxyphenol methoxyphenyl triazine ”is preferred. This bisethylhexyloxyphenol methoxyphenyl triazine is commercially available under the trade name of Tinosorb S from BASF, and the commercially available product can be used.

The aqueous dispersion of the oil-soluble ultraviolet absorber in the present invention is particularly preferably an aqueous dispersion of composite particles of the oil-soluble ultraviolet absorber and the organic polymer. By using the composite particles, the oil-soluble ultraviolet absorber is prevented from eluting from the aqueous phase to the oil phase when the water phase containing the water dispersion and the oil coexist.
An aqueous dispersion of composite particles of an oil-soluble ultraviolet absorber and an organic polymer can be prepared, for example, according to a method described in WO2009 / 007264. Briefly, it can be obtained as an aqueous dispersion in which composite particles of an ultraviolet absorber and an organic polymer are dispersed by emulsion polymerization in a state where the mixture of the ultraviolet absorber and the organic monomer is dispersed in water.
As the organic monomer, monomers having an ethylenically unsaturated bond, for example, acrylic acid, methacrylic acid, alkyl acrylate, alkyl methacrylate, styrene monomer, nylon monomer and the like are preferably used.

  As such an aqueous dispersion of composite particles, a product commercially available from BASF under the trade name of Tinosorb S Aqua can be used. Tinosorb S aqua contains composite particles of bisethylhexyloxyphenol methoxyphenyl triazine (Tinosorb S) and polymethyl methacrylate (PMMA) dispersed in water, and bisethylhexyloxyphenol methoxyphenyl triazine and PMMA. The content of is 20% by mass and 19% by mass, respectively.

The blending amount of the oil-soluble UV absorber in the composition of the present invention is 5% by mass or less, preferably 3% by mass or less, more preferably 0.01 to 3% by mass as a dry mass. If the blending amount is less than 0.01% by mass, sufficient ultraviolet light absorption ability cannot be obtained, and if it exceeds 5% by mass, there is a tendency to cause problems in stickiness.
For example, when converted as the amount of the aqueous dispersion (component a) containing 20% by mass of the ultraviolet absorber, the dispersion is 25% by mass or less, preferably 15% by mass or less, more preferably 0.05. It will mix | blend at -15 mass%.

The polyether-modified silicone (component b) in the oil-in-water emulsion cosmetic of the present invention is selected from those having an HLB (Si) of 5 to 10, preferably 5 to 9.
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 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 represented by the above formula is conventionally used as a surfactant in an oil-in-water emulsion or a water-in-oil emulsion containing 50% or more of ethanol (for example, international No. WO 97/002888 pamphlet and JP-A-10-306020), and no examples of using this in an oil-in-water emulsion having a small amount of alcohol are known.
The present invention is the first use of a polyether-modified silicone having an HLB (Si) of 10 or less, preferably 9 or less as a surfactant in an oil-in-water emulsion, and adjusting the blending amount of ethanol to increase the hydrophilic viscosity. By blending the agent, an oil-in-water emulsion is stably formed in the preparation, but after application to the skin or the like, it is phase-inverted to become a water-in-oil type and exhibits excellent water resistance.

  The compounding quantity of the polyether modified silicone (component b) 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 emulsified cosmetic of the present invention contains 5% by mass or more of ethanol (component c) 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 or exceeds 50% by mass, a stable oil-in-water emulsion may not be obtained.

The emulsified cosmetic of the present invention further contains a hydrophilic thickener (component d) as an essential component.
In the present invention, a polyether-modified silicone having an HLB (Si) of 10 or less, which has been used in water-in-oil emulsions in the past, is stable by simply changing to a general surfactant for oil-in-water emulsions. It was found that a stable oil-in-water emulsion was 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, natural water-soluble polymers include, for example, arabia gum, tragacanth gum, galactan, guar gum, carob gum, caraya gum, carrageenan, pectin, agar, quince seed (malmello), alge colloid (guckweed extract), starch (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 synthetic water-soluble polymers 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.
In particular, an acrylic polymer such as polyacrylamide (trade name “SEPIGEL 305, SEPPIC”, acrylic acid / alkyl methacrylate copolymer (trade name “Pemulene TR-1, NOVEON”)) gives a refreshing feel and water resistance. It is preferable at the point which is excellent in property.

  The blending amount of the hydrophilic thickener (component d) in the emulsified cosmetic of the present invention is 0.01 to 3% by mass, preferably 0.05 to 3% by mass, more preferably 0.2 to 1% by mass. is there. 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 emulsified cosmetic of the present invention further contains a polyol (component e) 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 blending amount of the polyol (component e) in the emulsified cosmetic of the present invention is 0.1 to 15% by mass, preferably 1 to 10% by mass, more preferably 3 to 7% by mass. When the blending amount is less than 0.1% 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.

The composition of the present invention may further contain other ultraviolet absorbers in addition to the oil-soluble ultraviolet absorber aqueous dispersion (component a) blended in the aqueous phase.
Other ultraviolet absorbers are preferably oil-soluble and soluble in the oil phase (inner phase), and those that absorb ultraviolet rays synergistically with the ultraviolet absorber (component a) present in the aqueous phase are preferred.
Such an ultraviolet absorber is not particularly limited, for example, methoxycinnamic acid derivative, diphenylacrylic acid derivative, salicylic acid derivative, paraaminobenzoic acid derivative, triazine derivative, benzophenone derivative, benzalmalonate derivative, anthranil derivative, Examples include imidazoline derivatives, 4,4-diarylbutadiene derivatives, and phenylbenzimidazole 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, dolometrizole polysiloxane, and the like.

  The emulsified composition of the present invention contains, in addition to the above essential components a to e and optionally other ultraviolet absorbers, other components conventionally used in cosmetics as long as the effects of the present invention are not impaired. You may do it. Specific examples include humectants, oils, buffers, chelating agents, preservatives, and the like.

  The emulsion composition of this invention can be manufactured according to the method conventionally used for manufacture of an emulsion. For example, an oil component and HLB (Si) 5 to 10 are added to an aqueous phase component containing an aqueous dispersion of UV absorber (component a), ethanol (component c), a hydrophilic thickener (component d), and a polyol (component e). The oil-in-water emulsion composition of the present invention can be obtained by adding the oil phase mixed with the polyether-modified silicone (component b) to the aqueous phase while stirring with a homomixer or the like.

  The oil-in-water emulsified composition of the present invention is fresh and fresh when used, and has a characteristic of forming a film having excellent water resistance after coating. Further, a hardly soluble ultraviolet absorber is stably blended in the aqueous phase, and optionally other ultraviolet absorbers are blended. Accordingly, when applied to the skin, a fresh and refreshing feel is obtained, and after application, a water-resistant film is formed on the skin, so that a certain UV protection power is maintained.

  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 and Comparative Examples)
An oil-in-water emulsion composition having the composition listed in Table 1 below was prepared. About the feeling of use of the obtained composition, each female sample was actually applied to the skin by 10 female professional panels, and the feeling of use (no squeaking) was evaluated according to the following criteria. The results are also shown in Table 1.
○: Eight or more people evaluated that there was no squeak.
(Triangle | delta): 3-7 persons evaluated that there was no squeak.
○: Two or less people evaluated that there was no squeak.

A sample of 18.87 μL of each composition of Example 1 and Comparative Example 1 was uniformly applied to the surface of a PMMA film (5 cm × 5 cm) at a rate of 0.75 mg / cm ² . After leaving for 15 minutes, the absorbance of each sample was measured using a spectrophotometer (U-4100: manufactured by Hitachi, Ltd.). The results are shown in FIG.

  Separately from the above, the oily mixture corresponding to Examples 1 and 2 in which the liquid oils of Examples 1 and 2 (cyclopentasiloxane, ethylhexyl methoxycinnamate, octocrylene) were mixed in the ratios shown in Table 1, and to bisethyl Further, xyloxyphenol methoxyphenyl triazine was added and heated to 70 ° C. to prepare an oily mixture corresponding to Comparative Example 1, and each was sealed in a 50 mL screw tube. These were cooled to 25 ° C., a small amount of bisethylhexyloxyphenol methoxyphenyl triazine was added in a solid state, and the mixture was stored at 0 ° C. for 1 week, and the stability of the oil phase was evaluated by microscopic observation of each mixture. The results are also shown in Table 1 with x when the amount of crystals more than the amount added was observed and ◯ when the amount of crystals more than the amount added was not observed.

* 1) Chinosorb S Aqua (manufactured by BASF)
* 2) BY11-030 (manufactured by Toray Dow Corning Silicone): 50% by mass of PEG / PPG-19 / 19 dimethicone and 50% by mass of cyclopentasiloxane. PEG / PPG-19 / 19 Dimethicone is a polyether-modified silicone having a molecular weight of 55000 represented by the following formula:
(In the above formula, m = 400, n = 10, a = 19, b = 19)

  As is apparent from Table 1, in Comparative Example 1 in which bisethylhexyloxyphenol methoxyphenyl triazine was blended in the oil phase, the stability was poor and crystals were formed at a low temperature (0 ° C.). On the other hand, Examples 1 and 2 in which bisethylhexyloxyphenol methoxyphenyl triazine was blended in the aqueous phase were excellent in stability. On the other hand, the comparative example 2 which mix | blended the fine particle titanium oxide instead of bisethylhexyl oxyphenol methoxyphenyl triazine was inferior in a usability | use_condition (no creaking).

  Further, from the results shown in FIG. 1, in the composition (Example 1) in which bisethylhexyloxyphenol methoxyphenyl triazine was mixed in the aqueous phase in the form of an aqueous dispersion, bisethylhexyloxyphenol methoxyphenyl triazine was added in the oil phase. It became clear that the ultraviolet absorptivity superior to the comparative example 1 mix | blended with was shown.

Next, an emulsification experiment with a composition in which the polyether-modified silicone (PEG / PPG-19 / 19 dimethicone) of HLB (Si) = 7 used in the above examples was replaced with various polyether-modified silicones listed in Table 2 below. Tried. As a result, “O” is an example in which a stable oil-in-water emulsion is obtained with small emulsified particles, “○ △” when the emulsified particles are large but stable, “Δ” and those that could not be emulsified were shown as “x” and are shown in Table 2.
As a result, in Comparative Examples 3 to 4 using a polyether-modified silicone having an HLB (Si) of less than 5, an oil-in-water emulsion excellent in stability could not be obtained.

A cosmetic comprising an oil-in-water emulsion composition was prepared according to the following formulation.
Formulation Example 1: Sunscreen emulsion ion-exchanged water Residual ethyl alcohol 20
Dipropylene glycol 3
Carbomer 0.1
Acrylic acid / alkyl acrylate (C10-30) copolymer 0.1
Polyacrylamide-containing liquid ^{* 1)} 0.5
Aminomethylpropanediol appropriate amount polyoxybutylene polyoxypropylene glycol 2
PEG / PPG-19 / 19 Dimethicone 2
Cyclopentasiloxane 2
Hydrogenated polyisobutene 2
Caprylyl methicone 3
Triethylhexanoin 2
2-Ethylhexyl paramethoxycinnamate 3
2-Cyano-3,3-diphenylacrylic acid-2′-
Ethylhexyl ester 3
Bisethylhexyloxyphenol methoxyphenyl triazine aqueous dispersion 5
Methylenebisbenzotriazolyltetramethylbutylphenol 1
Chelating agent appropriate amount ethyl paraben appropriate amount perfume appropriate amount * 1) SEPIGEL 305 (manufactured by SEPPIC)

Formulation Example 2: Sunscreen emulsion ion-exchanged water Residual ethyl alcohol 20
1,3-butylene glycol 3
Carbomer 0.15
Acrylic acid / alkyl acrylate (C10-30) copolymer 0.15
Aminomethylpropanol appropriate amount polypropylene glycol 3
PEG / PPG-19 / 19 Dimethicone 1.5
Dimethicone 1.5
Cyclopentasiloxane 2
Dimethylpolysiloxane 2
Isododecane 2
Pentaerythrityl tetraethylhexanoate 3
Bisethylhexyloxyphenol methoxyphenyl triazine aqueous dispersion 15
2-Ethylhexyl paramethoxycinnamate 5
4-t-butyl-4′-methoxydibenzoylmethane 2
Phenylbenzimidazolesulfonic acid 2
2-Hydroxy-4-methoxybenzophenone 2
Chelating agent Appropriate amount Phenoxyethanol Appropriate amount

Claims (4)

(A) containing an aqueous dispersion of an oil-soluble ultraviolet absorber in an aqueous phase (outer phase);
(B) 0.1 to 10% by mass of a polyether-modified silicone having 5 to 10 HLB (Si),
(C) 5-50% by weight of ethanol,
(D) 0.01 to 3% by weight of a hydrophilic thickener, and (e) 0.1 to 15% by weight or more of a polyol ,
The oil-soluble ultraviolet absorber of the component (a) is bisethylhexyloxyphenol methoxyphenyl triazine,
The (b) polyether-modified silicone has the following formula:
(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). Composition. The composition according to claim 1 , wherein the component (a) is an aqueous dispersion of composite particles of an oil-soluble ultraviolet absorber and an organic polymer. The composition according to claim 1 or 2 , wherein a blending amount of the oil-soluble ultraviolet absorber is 5% by mass or less. The composition according to any one of claims 1 to 3 , wherein the hydrophilic thickener component (d) is polyacrylamide and / or an acrylic acid / alkyl methacrylate copolymer.