JPH11130652A - Skin cosmetic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a skin cosmetic having excellent skin protecting effects and yet improving effects on chapped skin and moisture retaining ability. SOLUTION: This skin cosmetic contains (A) a water-swelling clay mineral having 1-5,000 nm average particle diameter by a dynamic light scattering method, >=30 mV absolute value of zeta potential by an electrophoretic scattering method and >=90% purity by powder X-ray diffraction method and (B) a low-molecular betaine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin cosmetic composition having an excellent effect of protecting the skin, and of improving the rough skin and the moisturizing ability.

[0002]

2. Description of the Related Art In recent years, skin troubles have increased due to a decrease in skin barrier function due to drying and allergic diseases.

[0003] In contrast, there are few examples of preparations made for the purpose of "protecting the skin". For a similar purpose, that is, for the purpose of not irritating the skin, a composition containing a less irritating surfactant or a less irritating preservative has been proposed.

[0004] Although these are certainly less irritating to the skin by the composition, they have no effect on irritation from others.

It is also widely known to add an anti-inflammatory agent when the skin is irritated due to a drying or allergic disease. However, the anti-inflammatory agent suppresses the inflammation that has already occurred, and It has no function to enhance the barrier function and protect the skin from external stimuli.

On the other hand, conventionally, clay minerals have properties such as adsorptivity, binding, suspending, swelling, film-forming, and viscosity increasing properties. Have been.

When such a clay mineral is blended in a cosmetic, the cosmetic is (1) non-sticky, has a smooth and refreshing feel, and (2) has good spreadability on the skin surface and forms a film. (3) thickens, (4) improves emulsion and suspension stability, (5) improves lotion and shampoo cleansing performance,
(6) It is known that properties such as improved washability with water or soap are imparted. That is, by blending the clay mineral, the liquid property of the cosmetic can be changed, and the texture and finish after use can be improved.

[0008] Further, the water-swellable clay mineral imparts the above-mentioned preferable feeling of use to cosmetics, and exhibits the same thickening effect as that of a polymer thickener. In addition, there is an advantage that the drainage of the cosmetic when removing the cosmetic from the container is improved.

Therefore, from the above effects, water-swellable clay minerals have hitherto been used in cosmetics such as foundations, packs, creams, soaps, and paste-like facial cleansers (Japanese Patent Application Laid-Open No. 61-43323). , Tokiko Sho 61-41
No. 891, JP-A-3-20227, JP-A-5
-345715).

[0010] The present applicant has previously found that these water-swellable clay minerals further have a skin protective effect such as an effect of suppressing keratinocyte intercellular lipid and NMF (natural moisturizing factor) elution and a stimulating effect. Have proposed a skin protective agent using the same (Japanese Patent Application No. 8-154613).

[0011] However, this skin protective agent is NMF
Although effective in the elution suppression effect and the stimulation suppression effect of the anionic surfactant, the effect of improving the skin that has already been roughened or the skin with reduced moisturizing ability, that is, the skin moisturizing effect, is insufficient.

On the other hand, low molecular betaines are used in cosmetics having a moisturizing action (Japanese Patent Laid-Open No. 6-293).
624, JP-A-8-92060). However, the skin protection effect of suppressing percutaneous absorption to external stimuli and suppressing the elution and reduction of keratinocyte intercellular lipids, natural moisturizing factors and water is not known, and the moisturizing effect is satisfactory. Has not been reached.

[0013]

SUMMARY OF THE INVENTION The present invention suppresses the transdermal absorption of water-swellable clay minerals against external stimuli,
An object of the present invention is to provide a skin cosmetic composition having a skin protective effect that suppresses the dissolution and reduction of keratin intercellular lipids, natural moisturizing factors and water, without impairing the skin protective effect, and further enhances the skin moisturizing effect. .

[0014]

Means for Solving the Problems The present inventors have further improved the above-mentioned skin-protecting effect and have an excellent skin moisturizing effect by blending a low-molecular-weight betaine with a specific water-swellable clay mineral. And completed the present invention.

That is, according to the present invention, the average particle diameter is 1 to 5000 nm by dynamic light scattering, the absolute value of the zeta potential is 30 mV or more by electrophoretic scattering, and the purity is 90% or more by powder X-ray diffraction. A skin cosmetic comprising a water-swellable clay mineral and low-molecular-weight betaine is provided.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the skin cosmetic of the present invention will be described in more detail. As the water-swellable clay mineral to be incorporated into the skin cosmetic of the present invention, natural or synthetic smectite clay,
In particular, non-organic metamorphic non-organic metamorphic smectite clay is preferred, including bentonite, montmorillonite, beidellite, nontronite, saponite, hectorite, sauconite, stevensite, and the like.
Swellable mica can also be used. Among them, bentonite, montmorillonite and saponite are preferred.

Further, the water-swellable clay mineral has an average particle size of 1 to 5000 nm measured by a dynamic light scattering method,
Further, those having an absolute value of zeta potential of 30 mV or more measured by electrophoretic light scattering and a purity of 90% or more determined by powder X-ray diffraction are used.

When the average particle size of the clay mineral is larger than 5000 nm, the surface area per unit weight of the clay mineral is small and the contact area of the skin surface is small, so that percutaneous absorption against external stimuli is suppressed and components are eluted between keratinocytes. Poor control effect.
The preferred average particle size is 1000 nm or less, and the more preferred average particle size is 700 nm or less.

The absolute value of the zeta potential of the water-swellable clay mineral is 30 mV or more, particularly 3 mV, from the amount adsorbed on the skin surface.
Those having 0 to 150 mV are preferred.

Furthermore, clay minerals, especially those collected from nature, contain non-swelling impurities such as calcite, tridymite, cristobalite, quartz, and various inorganic substances, and contain a large amount of these impurities. In this case, the above effect is insufficient, so that the purity of the clay mineral is preferably 90% or more, particularly preferably 95% or more.

In the skin cosmetic of the present invention, the amount of the specific water-swellable clay mineral is preferably at least 0.001% by weight, and at least 0.1% by weight in order to sufficiently exert its effect. Is more preferred. If it is less than 0.001% by weight, it is inferior in use feeling and skin protection effect. In addition, 1
If it exceeds 0% by weight, the dispersion stability tends to deteriorate,
The upper limit is preferably 10% by weight.

The low molecular weight betaine used in the present invention may include those having a molecular weight of 200 or less, such as quaternary ammonium bases, sulfonium bases and phosphonium bases, which form zwitterions. The reason for setting the molecular weight to 200 or less is that betaine having a molecular weight of more than 200 has properties as a surfactant and tends to roughen the skin. In the present invention, among these low molecular weight betaines, a quaternary ammonium salt represented by the following general formula (I) is preferably used.

[0023]

Embedded image (Wherein, R ¹ , R ² and R ³ each independently represent an alkyl group having 1 to 6 carbon atoms, n represents 0 or a positive integer, and the number of carbon atoms of R ¹ , R ² and R ³ is Is less than or equal to 8.

In the above general formula (I), R ¹ , R ² , R
The sum of the carbon number of ³ and n becomes 9 or more, and the molecular weight of the nitrogen atom and the alkyl groups (R ¹ , R ² and R ³ ) and the (CH ₂ ) _{n + 1} portion bonded to this nitrogen atom is relatively high. When the size of the quaternary ammonium salt increases, the hydrophobicity of the quaternary ammonium salt tends to increase, and as a result, the property of the quaternary ammonium salt as an amphoteric surfactant tends to become apparent, which is not preferable.

R ¹ , R ² and R ³ have 1 to 1 carbon atoms.
Six linear or branched alkyl groups can be widely used. That is, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, isohexyl, 3-methylpentyl group, 2,2-
Examples thereof include a dimethylbutyl group and a 2,3-dimethylbutyl group. Note that R ¹ , R ² , and R ³ may be the same or different from each other.

As a combination of the above alkyl groups,
By reducing the number of carbon atoms of R ¹ , R ² and R ³ as much as possible, the properties of the quaternary ammonium salt represented by the above general formula (I) as an amphoteric surfactant can be reduced as much as possible. This is preferable in that there is a tendency. That is, in the above general formula (I), trimethylglycine in which R ¹ , R ² and R ³ are all methyl groups and n is 0 is most preferably used. Further, in the above general formula (I), γ-butyrobetaine in which R ¹ , R ² and R ³ are all methyl groups and n is 2 is also preferably used.

The low molecular weight betaine is preferably incorporated in the skin cosmetic of the present invention at a ratio of 0.01 to 30% by weight,
More preferably, it is 0.1 to 10% by weight. If it is less than 0.01% by weight, the skin moisturizing effect cannot be exhibited,
Further, even if the content exceeds 30% by weight, the effect of the present invention cannot be expected to increase, and the stickiness is unfavorable in terms of feeling of use.

In the skin cosmetic of the present invention, in addition to the above essential components, compounding agents usually used in skin cosmetics, for example, surfactants, oils, alcohols, humectants, thickeners, preservatives, An antioxidant, a chelating agent, a pH adjuster, a fragrance, a pigment, an ultraviolet absorbing / scattering agent, vitamins, amino acids, water and the like can be added. The optional components are not limited to these.

The skin cosmetics of the present invention include various cosmetic creams, milky lotions, lotions, serums, packs, pre-make-ups, under-make-ups, foundations, gels, ointments and other external skin compositions, bath cosmetics. , Body rinse and the like.

[0030]

Industrial Applicability The skin cosmetic of the present invention is excellent in skin protection effect, and is also excellent in improving rough skin and improving moisturizing ability.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to embodiments. However, the present invention is not limited to the following embodiments. In addition, the composition of the skin cosmetics in Examples and Comparative Examples is shown by weight%.

In the following examples, the skin protection effect (N
The MF elution suppression effect test, the anion surfactant's irritation suppression effect test) and the skin moisturizing effect (skin roughness improving effect; skin surface horny layer moisture content measurement test, surface shape observation) were examined by the following methods.

<Skin Protective Effect> (1) NMF Elution Suppressing Effect Test Pyrrolidone carboxylic acid (PCA), which is one of NMF, was determined by the following method.

After applying a fixed amount (4 mg / cm ² ) of the sample to the inner part of the forearm of five panelists, 3 mL of a 0.15% by weight kitchen detergent was extracted for 15 minutes by a cup method.
The amount of PCA in the extract was determined by high performance liquid chromatography under the following conditions.

HPLC conditions Column TSKgel ODS80TM Column temperature 25 ° C. Mobile phase 1M sodium sulfate, 0.1% by weight phosphoric acid Flow rate 0.8-1.0 mL / min Injection amount 10 μL Detector UV 204 nm

The amount of PCA eluted when no sample was applied was 100
%, And the PCA amount at the time of sample application was expressed as a PCA elution amount ratio, and evaluated as follows.

(Evaluation) PCA elution amount ratio NMF elution inhibitory effect 0 to less than 25% ２ 25 to less than 50% ５０ 50 to less than 75% △ 75 to 100% ×

(2) Stimulation Inhibition Effect Test of Anionic Surfactant A fixed amount of a sample (2 mg /
cm ² ), and a closed patch test was performed for 24 hours using a fixed amount of a 0.5% by weight aqueous solution of SDS to evaluate the erythema score.

[0039]

The average score was compared with the score when the sample was not applied, and evaluated as follows.

[0041]

<Skin moisturizing test> (3) Skin roughness improving effect; skin surface keratin moisture content measurement test and surface shape observation The inside of the forearm of 20 panelists was acetone: ether =
The mixture was degreased with a 1: 1 mixed solvent to prepare rough skin. Thereafter, each sample was applied twice a day, and three days later, the skin moisturizing effect was evaluated by a skin surface keratin moisture content measurement test and observation of the surface shape by a replica method.

(Score) Significant effect: The symptoms of rough skin disappeared Effective: The symptoms of rough skin weakened Slightly effective: The symptoms of rough skin became slightly weaker Invalid: No change was observed in the symptoms of rough skin The symptoms of the rough skin include a decrease in the water content of the skin surface horny layer, exfoliation of the stratum corneum, erythema, skin sulcus and skin hills are not clear, and skin texture is not uniform.

(Evaluation) ：: 80% or more of the subjects evaluated highly effective, effective, and somewhat effective ：: 50% or more and less than 80% of the subjects evaluated highly effective, effective, and slightly effective Δ: Excellent 30% or more and less than 50% of subjects evaluated effective, effective, and somewhat effective ×: Less than 30% of subjects evaluated highly effective, effective, and somewhat effective

Examples 1-3, Comparative Examples Creams having the compositions shown in Table 1 were produced. The production method is that an oil phase composed of an oil component and an activator, an aqueous phase composed of a humectant, purified water, etc.
The mixture was dissolved at 0 ° C., and the oil phase was gradually added while stirring the aqueous phase to perform preliminary emulsification. Thereafter, an emulsifier (homomixer) treatment was performed to homogenize the emulsified particles, followed by degassing and cooling.

Here, the skin protection effect and the skin moisturizing effect were evaluated by the tests (1), (2) and (3).

[0047]

[Table 1] * 1: average particle diameter 450 nm, zeta potential -60 mV,
Purity 98% * 2: average particle size 215 nm, zeta potential -45 mV,
Purity 99% * 3: average particle diameter 910 nm, zeta potential -80 mV,
95% purity

Example 4 An emulsion having the following composition was prepared by a conventional method. Trimethylglycine 3% Bentonite * 4 1 Squalane 5 Silicone oil * 5 1 Isocetyl isostearate 1 Cetostearyl alcohol 1 POE (40) monostearate 1 Sorbitan monostearate 1 Stearyl glycyrrhetinate 0.1 Tocopherol acetate 0.2 Glycerin 3 L -Proline 0.1 L-Arginine 0.1 PCA Sodium 1 1,3-butylene glycol 2 Methylparaben 0.2 Citric acid trace amount Xanthan gum 0.3 Purified water Balance total 100% Property pH 6.5 Viscosity 1000 cp / 25 ° C Particle size 1 to 10 μm Appearance White milky liquid * 4: Average particle diameter 200 nm, zeta potential -35 mV, purity 98% * 5: SH200 (30 cs) (manufactured by Toray Dow Corning Silicone Co., Ltd.)

Example 5 An emulsion having the following composition was produced by a conventional method. Bentonite * 6 0.5% Trimethylglycine 3 Liquid paraffin 3 Silicone oil * 7 1 Isostearyl isostearate 2 Stearyl alcohol 1 POE (40) hydrogenated castor oil 1 Stearyl glycyrrhetinate 0.2 Glyceryl monostearate 1.5 Glycerin 5 di Propylene glycol 2 propylparaben 0.1 methylparaben 0.2 xanthan gum 0.3 citric acid trace amount citrate sodium trace amount hydroxyethanediphosphonic acid appropriate amount purified water balance fragrance trace amount total 100% property pH 5.0 viscosity 1000cp / 25 ° C particle size 1 Appearance White milky liquid * 6: Knipure G (Kunimine Industries) * 7: SH244 (Toray Dow Corning Silicone)

Example 6 A cosmetic solution having the following composition was prepared by a conventional method. Synthetic bentonite * 8 0.1% trimethylglycine 2 squalane 2 silicone oil * 9 1 octyldodecyl isostearate 1 hydrogenated soybean phospholipid 2 diglyceryl monostearate 2 dipotassium glycyrrhizinate 0.1 glycerin 10 sodium hyaluronate 0.05 citrate Acid trace Na citrate Trace POE (40) hydrogenated castor oil pyroglutamic acid 0.3 isostearic acid diester Purified water Balanced fragrance Total trace 100% Properties pH 6.5 Particle size 0.005 to 0.02 μm Appearance Translucent * 8: Smecton SA (Kunimine Industries) * 9: SH200 (10cs) (Toray Dow Corning Silicone)

Example 7 A cosmetic solution having the following composition was produced by a conventional method. Saponite * 10 2% Trimethylglycine 3 Light isoparaffin 6 Squalane 2 Silicone oil * 11 2 Jojoba oil 1 Isopropyl palmitate 1 Shea butter 1 Behenyl alcohol 2 POE (40) monostearyl alcohol 1 Sorbitan monostearate 1 Glycerin 5 1,3-butylene Glycol 2 Glycolic acid 1 Methyl paraben 0.2 Xanthan gum 0.2 Citric acid Trace amount of sodium hydroxide Appropriate amount Purified water Balance 100% Property pH 4.0 Viscosity 6000 cp / 25 ° C Particle size 1-10 μm Appearance White milky liquid * 10: Vegum HV (Vanderwirt) * 11: KF945A (Shin-Etsu Chemical Co., Ltd.)

Example 8 A pack having the following composition was produced by a conventional method. Bentonite * 12 2% Trimethylglycine 3 Squalane 3 Silicone oil * 13 1 Isopropyl palmitate 1 POE (40) monostearyl alcohol 2 Sorbitan monostearate 2 Glycerin 10 Polyvinyl alcohol * 14 12 Titanium oxide 2 Methyl paraben 0.2 Purified water Balance total 100% Properties pH 5.0 Viscosity 350 cp / 25 ° C. Particle Size 1-10 μm Appearance White cream * 12: Knipure G (manufactured by Kunimine Industries) * 13: KF96A 1cs (manufactured by Shin-Etsu Chemical) * 14: Gohsenol EG- 30 (manufactured by Nippon Synthetic Chemical Industry Co., Ltd.)

Example 9 Whitening Agent Bentonite 0.4% Trimethylglycine 0.2 Liquid Paraffin 10.0 Isopropyl Myristate 1.5 Decaglycerin Monostearate 1.0 Glycerin Diisostearate 0.5 Stearic Acid 1 .5 POE (20) stearyl alcohol 0.8 glycyrrhetinic acid 0.1 glycerin 3.0 proline 0.1 ethanol 2.0 urea 1.0 ellagic acid 0.3 carboxyvinyl polymer * 15 0.1 triisopropanolamine qs perfume Trace amount of purified water Total balance 100% Properties pH 6.5 Viscosity 150 cp / 25 ° C Particle size 1-10 μm Appearance Cream * 15: PN 111 (manufactured by Nippon Pure Chemical Co., Ltd.)

Example 10 Acne Treatment Agent Laponite 0.4% Trimethylglycine 0.2 Stearyl Glycyrrhetinate 2.0 L-Proline 0.05 Oil-soluble Licorice Extract 0.3 Urea 0.2 Liquid Paraffin 3.0 Squalane 10.0 Cetostearyl alcohol 4.0 Beeswax 2.0 Glycerin monostearate 2.0 POE (20) Sorbitan monolaurate 2.0 Glycolic acid 0.2 Salicylic acid 0.1 Sulfur 5.0 Diglycerin 5.0 Resorcinol 0.2 Sodium hydroxide Trace amount Perfume Trace amount purified water Total balance 100% Properties pH 3.5 Viscosity 200 cp / 25 ° C Particle size 1-10 μm Appearance Cream

Example 11 Powder Spray Type Antiperspirant Bentonite * 16 0.2% Trimethylglycine 0.5 Chlorohydroxyaluminum (10 μm) 4.0 Magnesia Silica (10 μm) 3.0 Silicic Anhydride (10 μm) 4.0 0 Isopropyl myristate 3.0 Methylcyclopolysiloxane (4.0 cst) 1.5 Decamethylpentasiloxane 3.0 Sorbitan trioleate 0.5 Stearyl glycyrrhetinate 0.02 Vegetable squalane 0.1 Triclosan 0.2 Fragrance 0 .2 Petroleum liquefied gas balance 100% in total pH 4.5 * 16: Benclay (manufactured by Mizusawa Chemical Industry Co., Ltd.)

Example 12 Sterilized Soap Montmorillonite 0.4% Trimethylglycine 0.2 Dipotassium glycyrrhizinate 0.1 L-Proline 0.1 Palm / palm oil (30/70) Fatty acid Na 84.0 Palm / palm oil (30/70) Fatty acid 3.0 Dibutylhydroxytoluene 0.1 EDTA.2Na 0.1 Hydroxyethanediphosphonic acid 0.1 Citric acid 0.5 Triclosan 0.2 Fragrance 2.0 Titanium oxide 0.4 Purified water Balance 100% in total

Example 13 Liquid Skin Cleanser Montmorillonite 0.4% Trimethylglycine 0.2 Dipotassium glycyrrhizinate 0.1 L-Proline 0.1 Klaurate K 10.0 10.0 K myristate 10.0 N Lauroyl N-methyl β-alanine K salt 2.0 N lauroylglutamic acid mono-K salt 2.0 coconut oil fatty acid diethanolamide 3.0 lauryl dimethylamine oxide 1.0 propylene glycol 6.0 hydroxypropyl methylcellulose (Mw = 40,000) 0.5 Ethylene glycol distearate 1.0 Cationized cellulose 0.1 Polystyrene polymer (n = 300) 0.1 Tetrasodium tetrasodium edetate 0.1 Perfume Micro- purified water Total balance 100% Property pH 5.0 Viscosity 1500 cp / 25 ° C

The cosmetics prepared in Examples 4 to 13 were all excellent in skin protection effect and skin moisturizing effect.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI A61K 7/38 A61K 7/38 7/50 7/50

Claims (1)

[Claims] (A) An average particle diameter of 1 determined by a dynamic light scattering method.
５5000 nm, absolute value of zeta potential by electrophoretic scattering method of 30 mV or more, and purity by powder X-ray diffraction method of 9
A skin cosmetic comprising: 0% or more of a water-swellable clay mineral; and (B) a low molecular weight betaine.