JP4264327B2 - Skin cosmetics - Google Patents

Description

The present invention relates to a W / O / W type emulsified skin cosmetic excellent in skin aging prevention effect.

  In aging skin, the cell activity of the epidermis and dermis is reduced, and as a result, dry skin due to the function of the stratum corneum and skin with no elasticity due to the function of the dermal fibroblasts. As a result, the skin of the elderly tends to be in a sagging state without firmness. Conventionally, various cell activators have been searched for in order to recover the activity of such aging skin. Among them, an extract of a plant belonging to the genus Birch, alder of the birch family (for example, birch, alder) remarkably promotes the proliferation of epidermal cells and improves the function of the stratum corneum. (JP-A-6-263627). However, among these plant extracts, plant extracts extracted with water-soluble solvents such as water, ethanol, and polyhydric alcohol have high water solubility, and when applied to the skin, they are not easily absorbed due to the presence of sebum and are sufficient. There was a problem that it was difficult to obtain the effect. In order to improve such problems, a technique relating to a skin external preparation that contains a water-soluble medicinal component in the inner aqueous phase of a W / O / W emulsion and is excellent in transdermal absorbability has been disclosed. (Japanese Unexamined Patent Publication No. 2000-239157). However, it is difficult for W / O / W type emulsions to ensure stability, and there remains a problem that it is difficult to maintain stability as a cosmetic.

JP-A-6-263627 JP 2000-239157 A

  An object of the present invention is to provide a W / O / W type emulsified skin cosmetic having good stability and excellent skin aging prevention effect in a W / O / W type emulsion containing a birch bark extract in the inner aqueous phase. There is to do.

As a result of intensive studies, the present inventors have found that a W / O / W type emulsified skin cosmetic containing a birch bark extract in the inner aqueous phase and containing a fatty acid ester oil at room temperature in the oil phase has good stability. It has been found that it has an excellent anti-skin aging effect and has led to the completion of the invention.

The present invention provides the inventions described in the following items.
Item 1. A W / O / W emulsified skin cosmetic comprising a birch bark extract in an inner aqueous phase.
Item 2. The W / O / W-type emulsified skin cosmetic according to Item 1, which contains a fatty acid ester oil that is liquid at room temperature.
Item 3. The W / O / W type emulsified skin cosmetic according to Item 2, wherein the fatty acid ester oil that is liquid at normal temperature is a branched fatty acid ester oil.
Item 4 The W / O / W type emulsified skin cosmetic according to Item 3, wherein the branched fatty acid ester oil is isostearyl isostearate.

The present invention is described in detail below.
The birch bark extract used in the present invention is an extract obtained by extracting birch bark with water, ethanol, 1,3-butylene glycol or a mixture thereof, and birch extract (Maruzen Pharmaceutical), birch extract BG ( Maruzen Pharmaceutical), birch extract LA (Maruzen Pharmaceutical), and the like are commercially available.
The amount of birch bark extract is not particularly limited, but is usually about 0.0001 to 5% by weight, particularly preferably about 0.001 to 2% by weight, more preferably 0.005 to 1 in terms of dry weight. It is about wt%.

The room temperature liquid fatty acid ester oil used in the present invention is a component in which a fatty acid and an alcohol are ester-bonded, and is commercially available. The normal temperature in the present invention is 20 ° C. to 30 ° C., and the one that exhibits a liquid state at this temperature is a normal temperature liquid fatty acid ester oil. In the present invention, normal temperature liquid fatty acid ester oil is not particularly limited, and specifically, diisobutyl adipate, diethylhexyl succinate, cetyl 2-ethylhexanoate, glyceryl tri-2-ethylhexanoate, ethylhexane Hexyldecyl acid, triethylhexanoin, neopentyl glycol diethylhexanoate, trimethylolpropane triethylhexanoate, pentaerythrityl tetraethylhexanoate, neopentyl glycol dicaprate, ethylhexyl isononanoate, isononyl isononanoate, isodecyl isononanoate, isotridecyl isononanoate Hexyl laurate, isopropyl myristate, octyldodecyl myristate, isocetyl myristate, isopropyl palmitate, ethyl hexyl palmitate, Octyl palmitate, ethyl stearate, octyl stearate, isocetyl stearate, ethyl isostearate, isopropyl isostearate, hexyldecyl isostearate, isostearyl isostearate, glyceryl triisostearate, polyglyceryl triisostearate, trimethylolpropane triisostearate , Pentaerythrityl tetraisostearate, ethyl oleate, glyceryl tri (capryl / caprate), octyldodecyl 12-stearoyl stearate, and the like.

Among them, branched fatty acid esters are preferable, and specifically, cetyl 2-ethylhexanoate, glyceryl tri-2-ethylhexanoate, hexyldecyl ethylhexanoate, triethylhexanoin, neopentyl glycol diethylhexanoate, trimethylol triethylhexanoate. Propane, pentaerythrityl tetraethylhexanoate, ethylhexyl isononanoate, isononyl isononanoate, isodecyl isononanoate, isotridecyl isononanoate, ethyl isostearate, isopropyl isostearate, hexyldecyl isostearate, isostearyl isostearate, glyceryl triisostearate, triisostearate Polyglyceryl acid, trimethylolpropane triisostearate, pentaerythrityl tetraisostearate Is preferred, and isostearyl isostearate is particularly preferred.

The blending amount of the room temperature liquid fatty acid ester in the cosmetic of the present invention can be appropriately set in the invention capable of achieving the intended effect of the present invention, but usually, based on the total weight of the cosmetic of the present invention, 0. It is about 001 to 60% by weight, preferably 0.001 to 50% by weight, more preferably about 0.1 to 40% by weight, and most preferably 0.5 to 30% by weight.

The skin cosmetic of the present invention can be provided in a known form (for example, a liquid for external use such as a lotion or emulsion, a cream, an ointment, etc.) as long as it can be applied to the skin, and more specifically, a skin lotion. , Skull lotion, hair tonic, emulsion, foundation, massage cream, eye cream, face cream, hand cream, body lotion, body cream and the like.

According to the form of the cosmetic of the present invention, appropriate additives, bases, diluents and the like can be appropriately blended. For example, oil, UV absorber, powder, antioxidant, surfactant, preservative, fragrance, water, thickener, pigment, medicinal agent, pH adjuster, colorant, fragrance, specifically water Ethanol, hydroxyethyl cellulose, xanthan gum, carbomer, glycyrrhizic acid and derivatives thereof, glycyrrhetinic acid and derivatives thereof, allantoin, vitamin E and derivatives thereof, sodium hyaluronate, sodium pyrophosphate, amino acids, hydrolyzed proteins, peptides and the like Derivatives, silicone oil, olive oil, almond oil, macadamia nut oil, squalane, liquid paraffin, oleic acid, stearic acid, isostearyl alcohol, behenyl alcohol, polyethylene glycol, glycerin, 1,3-butylene glycol, propylene glycol A range that does not impair the intended effect of the present invention, such as alcohol, dipropylene glycol, dibutylhydroxytoluene, paraben, citric acid, sodium citrate, potassium hydroxide, sodium hydroxide, sodium phosphate, ethylenediaminetetraacetate, and fragrance Thus, it can be appropriately blended as necessary.

  The W / O / W type emulsified skin cosmetic of the present invention is prepared by dispersing in a liquid or fluid that becomes an inner aqueous phase to prepare a W / O type emulsion, and further dispersed in a liquid that becomes the outer aqueous phase of the emulsion. When preparing an emulsion, heat may be applied as necessary. As a more specific example, an aqueous phase containing birch bark extract is introduced into an oil phase containing a surfactant, emulsified using a homogenizer, a high-pressure homogenizer, ultrasonic emulsification, etc., and a W / O emulsion The W / O type emulsion thus obtained is put into an external aqueous phase containing a surfactant and emulsified by propeller stirring or the like to obtain a W / O / W type emulsified skin cosmetic.

As the surfactant contained in the oil phase, it can be used by appropriately selecting from commonly used nonionic surfactants, cationic surfactants and amphoteric surfactants.
These are not particularly limited, but examples of nonionic surfactants include dipolyhydroxy fatty acid polyethylene glycol, monopolyhydroxy fatty acid polyethylene glycol, polyhydroxy fatty acid polyglyceryl, mono fatty acid glyceryl, mono fatty acid polyglyceryl, and difatty acid glyceryl. , Difatty acid polyglyceryl, trifatty acid glyceryl, trifatty acid polyglyceryl, pentafatty acid polyglyceryl, fatty acid sorbitan, sesquifatty acid sorbitan, trifatty acid sorbitan, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, etc. . Examples of the cationic surfactant include distearyldimethylammonium chloride. Examples of amphoteric surfactants include lecithin or derivatives thereof.

As the surfactant contained in the outer aqueous phase, it can be used by appropriately selecting from commonly used nonionic surfactants, cationic surfactants, amphoteric surfactants and anionic surfactants. . Although these are not particularly limited, for example, nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl ether, Examples thereof include oxyethylene sorbite fatty acid ester, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkylphenyl ether, polyglycerin fatty acid ester, and fatty acid polyglyceryl. Examples of the cationic surfactant include cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, and behenyltrimethylammonium chloride.
Examples of amphoteric surfactants include alkyldimethylaminoacetic acid betaines, alkylamidodimethylaminoacetic acid betaines, 2-alkyl-N-carboxy-N-hydroxyimidazolinium betaines. Examples of the anionic surfactant include alkyl sulfate ester salt, polyoxyethylene alkyl ether sulfate ester salt, α-olefin sulfonate salt, monoalkyl phosphate ester salt, polyoxyethylene monoalkyl ether phosphate ester salt, monoalkyl sulfosuccinic acid. Ester salt, polyoxyethylene alkyl acetate salt, fatty acid soap, polyoxyethylene alkyl monoethanolamide sulfate ester, N-acyl glutamate, N-acyl-N-alkyl amino acid, acylated peptide, α-sulfo fatty acid methyl ester Examples include salt.

In the W / O / W type emulsified skin cosmetic of the present invention, the weight ratio, volume ratio, average particle size of W / O emulsion particles, and the like of the inner water phase, the oil phase and the outer water phase can be appropriately set according to the form. .
The pH in the cosmetic of the present invention is not particularly limited, but is usually about 3 to 12, particularly preferably about 5 to 8.

Next, the present invention will be described in more detail with reference to Production Examples, Examples, Comparative Examples, Test Examples, and Formulation Examples, but the present invention is not limited thereto. Unless otherwise specified, [%] represents [% by weight].

Production Example of W / O / W Type Emulsified Skin Cosmetics A heated A was used as a dispersed phase and B was used as a continuous phase to perform emulsification using a homogenizer to obtain a W / O type emulsion. Subsequently, the W / O type emulsion obtained above was dispersed in C using a propeller stirrer to obtain a W / O / W type emulsified skin cosmetic.
Production Example of O / W Emulsion Emulsification was performed using a homogenizer with heated B as the dispersed phase and C as the continuous phase to obtain an O / W type emulsion.
Example of production of aqueous phase A birch bark extract was mixed with a predetermined amount of ion-exchanged water.

Test example 1
The skin aging symptom improvement effect of the emulsions or aqueous solutions obtained in Examples 1 to 3 and Comparative Examples 1 to 4 was evaluated. The effect of improving skin aging symptoms was evaluated by observing changes in skin condition before and after use. Skin wrinkles and textures were evaluated for improvement from photography. The improvement status was evaluated in four stages: ◎: large improvement effect, ○: improvement, Δ: slight improvement, ×: no change.
The results are shown in Table 1.

About Examples 1-3 which mix | blended the birch bark extract in the inner water phase, all showed the wrinkle improvement effect outstanding compared with Comparative Examples 1-4.

Test example 2
The stability of W / O / W emulsions in which the birch bark extracts of Examples 4 to 7 and Comparative Examples 5 to 9 were blended in the inner aqueous phase was examined.
The obtained emulsion was allowed to stand at 40 ° C., and stability was evaluated by observing the form of the emulsion under a microscope after one month.
Evaluation A: Good W / O / W emulsion particles ○: Good but partially rough W / O / W emulsion particles Δ: Mostly coarse W / O / W emulsion particles ×: W / O / Table 2 shows the results obtained when no W emulsion was obtained.

About Examples 4-7, all showed the outstanding stability compared with Comparative Examples 5-9. Example 4 was particularly stable.

The formulation example of this invention skin cosmetics is shown below. The compounding amount% indicates weight%.
Example 8 W / O / W type skin care cream
Ingredient amount%
(Phase A)
Birch bark extract powder (water extract) 0.1
Water 17.8
Sodium chloride 0.1
(Phase B)
Isostearyl isostearate 12.0
Sorbitan monooleate 1.2
(Phase C)
Acrylates / Beheneth-25 methacrylate-25) Copolymer 0.6
Xanthan gum 0.5
Decaglyceryl monolaurate 0.2
Glycerin 5.0
Potassium hydroxide appropriate amount (adjusted to pH 7.5)
Methyl paraoxybenzoate Appropriate perfume
Total 100.0
A W / O emulsion was prepared using a homogenizer with heated A as the dispersed phase and B as the continuous phase. Next, W / O / W type skin cream was prepared with a propeller stirrer using the obtained W / O emulsion as a dispersed phase and C as a continuous phase.

Example 9 W / O / W type emulsion
Ingredient amount%
(Phase A)
Birch bark extract powder 1.0
(1,3-butylene glycol / water mixture extract)
Potassium chloride 0.02
Chlorhexidine hydrochloride 0.05
Water 5.0
(Phase B)
Ethyl isostearate 8.0
Hexaglyceryl polyricinoleate 1.0
(Phase C)
Polyoxyethylene oleyl ether 0.5
1,3-butylene glycol 8.0
Concentrated glycerin 3.0
Methyl paraoxybenzoate appropriate amount carboxyvinyl polymer 0.2
Xanthan gum 0.2
Potassium hydroxide appropriate amount (adjusted to pH 7.5)
Potassium chloride 0.02
Purified water remaining
Total 100.0
A W / O emulsion was prepared using a homogenizer with heated A as the dispersed phase and B as the continuous phase. Next, a W / O / W emulsion was prepared with a propeller stirrer using the obtained W / O emulsion as a dispersed phase and C as a continuous phase.

Example 10 W / O / W Skin Lotion
Ingredient amount%
(Phase A)
Birch bark extract powder (water extract) 0.005
Water 5.0
(Phase B)
Isopropyl isostearate 2.0
Hexaglyceryl polyricinoleate 0.4
(Phase C)
Polyoxyethylene stearyl ether 0.5
1,3-butylene glycol 2.0
Methyl paraoxybenzoate Concentrated glycerin 1.0
Xanthan gum 0.04
Citric acid appropriate amount Sodium citrate appropriate amount (adjusted to pH 7.5)
Glycerin 5.0
Purified water remaining
Total 100.0
A W / O emulsion was prepared using a homogenizer with heated A as the dispersed phase and B as the continuous phase. Next, W / O / W type skin lotion was prepared with a propeller stirrer using the obtained W / O emulsion as a dispersed phase and C as a continuous phase.

Example 11 W / O / W-type skull propagation
Ingredient amount%
(Phase A)
Birch bark extract powder 0.01
(Ethanol / water mixed extract)
Water 5.0
(Phase B)
Ethyl oleate 3.0
Hexaglyceryl polyricinoleate 0.5
(Phase C)
Polyoxyethylene stearyl ether 0.5
1,3-butylene glycol 3.0
Polyoxyethylene hydrogenated castor oil 0.5
Methyl paraoxybenzoate Appropriate amount Carboxyvinyl polymer 0.05
Sodium hydroxide appropriate amount (adjusted to pH 7.5)
Menthol 0.01
Perfume Appropriate amount of purified water Remaining amount
Total 100.0
A W / O emulsion was prepared using a homogenizer with heated A as the dispersed phase and B as the continuous phase. Next, a W / O / W type skull proportion was prepared with a propeller stirrer using the obtained W / O emulsion as a dispersed phase and C as a continuous phase.

Claims (2)

One or more branched fatty acid ester oils selected from the group consisting of isostearyl isostearate, ethyl isostearate and cetyl ethylhexanoate in the dispersed phase and hexaglyceryl polyricinoleate, and birch bark extract in the inner aqueous phase W / O / W type emulsified skin cosmetic.   The W / O / W type emulsified skin cosmetic according to claim 1, wherein the branched fatty acid ester oil is isostearyl isostearate.