JP4814675B2 - Topical skin preparation - Google Patents

Description

  The present invention relates to an external preparation for skin containing α-lipoic acid and / or a derivative thereof, phospholipid, cholesterol, oil-soluble antioxidant, water-soluble antioxidant, and more specifically α-lipoic acid and / or its The present invention relates to an external preparation for skin in which the sulfur odor generated with the aging of the derivative is suppressed.

Conventionally, in skin external preparations such as cosmetics, sulfur compounds such as α-lipoic acid have been used for the purpose of imparting keratolytic effect, bactericidal effect, antioxidant effect, whitening effect, hair nourishing effect, anti-dandruff effect, etc. (For example, see Patent Documents 1, 2, and 3). In addition, nitrogen-containing compounds, water-soluble reducing agents, chelating agents, and the like have been used for the purpose of preventing odor change over time of bases and active ingredients in external preparations for skin and the like (for example, Patent Documents 4, 5 and 5). reference). Attempts have also been made to improve the antioxidant effect by using liposomes composed of phospholipids and cholesterol and specific antioxidants.
Japanese Patent Application Laid-Open No. Sho 62-175415 (pages 1 to 5) JP-A-63-8315 (pages 1 to 6) JP-A-2-145507 (pages 1 to 4) Japanese Patent No. 3434635 (pages 1 to 6) Japanese Patent No. 3497932 (pages 1 to 5) Japanese Patent No. 3521517 (pages 1 to 4)

  However, in a skin external preparation containing a sulfur compound such as α-lipoic acid and water, α-lipoic acid changes over time to generate a sulfur compound, and an unpleasant sulfur odor due to this is generated. There was a sexual problem. For this reason, as an attempt to improve the stability of α-lipoic acid, attempts have been made to encapsulate such as inclusion in cyclodextrin, but it has not yet sufficiently suppressed the generation of sulfur odor over time. It was the current situation.

  As a result of intensive studies in the above situation, the present inventor has encapsulated α-lipoic acid and / or a derivative thereof in a lipid bilayer composed of phospholipid and cholesterol, and further has an oil-soluble antioxidant and a water-soluble antioxidant. It has been found that the combined use of an oxidizing agent can suppress the alteration of α-lipoic acid and / or its derivatives, and the present invention has been completed by applying this to a topical skin preparation.

That is, the present invention includes the following components (A) to (F);
(A) α-lipoic acid and / or derivative thereof (B) phospholipid (C) cholesterol (D) oil-soluble antioxidant (E) water-soluble antioxidant (F) water It relates to an external preparation.

  Furthermore, the component (D) relates to a skin external preparation characterized by being one or two oil-soluble antioxidants selected from dibutylhydroxytoluene and tocopherol acetate.

  Further, the skin external preparation, wherein the component (E) is one or two or more water-soluble antioxidants selected from α-glucosyl rutin, mica (hamamelis) extract, and melosria extract. Is.

  The present invention also relates to a skin external preparation characterized in that the external preparation for skin is liquid.

  The skin external preparation is also an oil-in-water type. Is to provide. Furthermore, the present invention relates to a skin external preparation characterized in that component (A) is encapsulated in a lipid bilayer composed of components (B) and (C).

  The skin external preparation of the present invention is excellent in the effect of suppressing the deterioration of α-lipoic acid and its derivatives over time and preventing the generation of sulfur odor.

Hereinafter, the present invention will be described in detail.
Component (A) α-lipoic acid and / or a derivative thereof used in the present invention is blended for the purpose of keratolytic effect, bactericidal effect, antioxidant effect, whitening effect, hair nourishing effect, anti-dandruff effect and the like. Yes, as long as it is used as an ordinary cosmetic material, for example, lipoic acid, potassium salt of lipoic acid, sodium salt, methyl ester, ethyl ester, dodecyl ester, oleyl ester, stearyl ester, par Esters such as mithyl ester, palmitooleyl ester, benzyl ester, dihydrolipoic acid, dihydrolipoic acid potassium salt, sodium salt, methyl ester, ethyl ester, dodecyl ester, oleyl ester, stearyl ester, palmityl ester, palmitooleyl ester, Benzyl ester, cinnax , And amino acid condensates and the like. These α-lipoic acid and / or derivatives thereof may be used alone or in combination of two or more as required.

  Although the compounding quantity of the component (A) in this invention is not specifically limited, 0.001-1 mass% (Hereinafter, it only describes as "%") is preferable, and 0.01-0.1% More preferred. When the component (A) is contained in this range, the blending effect and stability over time are good.

The component (B) phospholipid used in the present invention is blended for the purpose of suppressing emulsification, dispersion and deodorization of the component (A). Specific examples include phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, sphingophospholipid and the like. Further, substances containing these, that is, soybean lecithin, egg yolk lecithin, or hydrogenated products thereof can be used in the same manner. Moreover, these phospholipids can be used by appropriately selecting one kind or two or more kinds as required.

  Although the compounding quantity of the component (B) in the skin external preparation of this invention is not specifically limited, It can determine suitably according to a compounding mass ratio with a component (A). Specifically, the blending mass ratio of component (A) / component (B) is preferably 1/10 to 1/1000. When the amount of the component (B) is blended in this range, an external preparation for skin having an excellent odor control effect can be obtained.

The component (C) cholesterol used in the present invention is blended together with the component (B) for the purpose of suppressing emulsification and dispersion stability of the component (A) and deodorizing.

  Although the compounding quantity of the component (C) in the skin external preparation of this invention is not specifically limited, The compounding mass ratio of a component (B) / component (C) is 1 / 0.1 to 1/1. It is preferable. When a component (C) is mix | blended in this range, the skin external preparation excellent in the deodorizing suppression effect and storage stability can be obtained.

The component (D) oil-soluble antioxidant used in the present invention is blended with a skin external preparation for the purpose of suppressing the odor change of the component (A). Specific examples include dibutylhydroxytoluene, tocopherol acetate, and the like, and these oil-soluble antioxidants can be appropriately selected from one or more as necessary.

  Although the compounding quantity of the component (D) in the skin external preparation of this invention is not specifically limited, It can determine suitably according to a compounding mass ratio with a component (A). Specifically, the blending mass ratio of component (A) / component (D) is preferably 1/1 to 1/100. When the amount of the component (D) is blended in this range, a skin external preparation excellent in a deodorizing effect can be obtained.

The component (E) water-soluble antioxidant used in the present invention is blended with the external preparation for skin for the purpose of suppressing the odor change of the component (A). Specific examples include α-glucosyl rutin, mica (Hananus) extract, melosria extract, etc., and these water-soluble antioxidants may be used by appropriately selecting one or two kinds as necessary. it can.

  The blending amount of component (E) in the external preparation for skin of the present invention is not particularly limited and varies depending on the type of component (E), but the blending mass ratio with component (A) is component (A) / The blending mass ratio of component (E) is preferably 1 / 0.1 to 1/100. When the component (E) is blended in this range, a cosmetic having an excellent odor control effect can be obtained. In addition, when a component (E) is an extract, the compounding quantity is a dry solid content density | concentration.

  Moreover, since the odor of the external preparation for skin can be suppressed by the method of the present invention, it is not necessary to mask with a fragrance as conventionally attempted, and therefore, the amount of the fragrance is reduced, or No fragrance can be added.

  In the external preparation for skin of the present invention, in addition to the above-mentioned essential components, for example, powders, surfactants, oil agents, water-soluble polymers, alcohols, gelling agents, film formation are commonly used as cosmetic ingredients. Contains agents, resins, ultraviolet absorbers, humectants, pH adjusters, antiseptics, antibacterial agents, fragrances, antioxidants, metal sequestering agents, colorants, cosmetics, and the like within a range that does not impair the effects of the present invention. be able to.

  Moreover, when the property of the external preparation for skin of the present invention is liquid, the effects of the present invention can be effectively exhibited. The liquid state in the present invention is when the viscosity of the external preparation for skin is in the range of 10 to 2000 mPa · s at 25 ° C. By using the effect of the present invention, a deodorizing effect can be obtained, so that a liquid skin external preparation having a good feel can be obtained.

  In addition, examples of the dosage form of the external preparation for skin of the present invention include oil-in-water type, oil-in-water-in-oil type, and water-in-oil-in-water type as examples that remarkably exhibit a deodorizing effect. The effect of this invention can mix | blend a component (A) and a component (D) more uniformly by mix | blending oil, The effect becomes remarkable. Among these dosage forms, the oil-in-water type is more preferable as ease of application to formulation.

  Moreover, since the component (B) can enclose a component (A) by forming a lipid bilayer membrane in water, the odor change over time can be better prevented. A method for forming such a lipid bilayer membrane is not particularly limited as long as it is a generally known method. Specifically, component (A) is mixed in advance with a system containing phospholipid and cholesterol. And a method of encapsulating by adding an aqueous system while stirring. In addition to this, a method using ultrasonic waves, a method using a homogenizer under pressure, or the like can be given. The particle size of the lipid bilayer membrane is not particularly limited, but is preferably 100 to 300 nm from the viewpoint of stability over time.

  The form of the external preparation for skin of the present invention is not particularly limited, and any of liquid, emulsion, gel, and cream may be used. In addition, basic cosmetics such as lotion, milky lotion, cream, sunscreen, pack, massage, beauty liquid, cleansing, cleaning, makeup cosmetics such as foundation, whitening powder, concealer, hair cosmetics, body It can be used in cosmetics, limb cosmetics, bath preparations and the like.

  EXAMPLES Next, although an Example is given and this invention is further demonstrated, this invention is not limited at all by this.

Invention products 1 to 16 and comparative products 1 to 4: beauty essence Beauty essences having the compositions shown in Tables 1 to 3 below are prepared by the following production methods, and the odor control effect is evaluated and determined by the method described below. The results are also shown in Tables 1 to 3.

(Production method)
A: Components (1) to (8) are heated to 70 ° C. and dissolved.
B: Components (9) to (15) are heated to 70 ° C. and dissolved.
C: While A is being stirred, B is gradually added and pre-emulsified.
D: C is cooled to room temperature and emulsified with a high-pressure emulsifier.
E: (16) dissolved in a part of the component (9) was added to D and mixed uniformly to obtain a cosmetic liquid.

(Evaluation methods)
After leaving the essence at room temperature under fluorescent light for 2 weeks, a panel of 10 perfume specialist panels performs sensory evaluation of odors and judges the effectiveness of the odor control effect based on the following (a) effectiveness rank. The average value was calculated from the total score of all the members and judged according to the following (b) criteria.
(A) Effectiveness rank 4 points: There is no generation of sulfur odor.
3 points: There is almost no generation of sulfur odor and commercialization with no fragrance is possible.
2 points: Sulfur smell is slightly generated, but masking with a small amount of fragrance is possible.
1 point: The generation of sulfur odor is remarkable and masking with fragrance is impossible.
(B) Judgment criteria ◎: Average score is 3 or more ○: Average score is 2 or more ×: Average score is less than 2

  As is clear from the results in Tables 1 to 3, the cosmetic liquids of the present invention products 1 to 16 did not generate sulfur odor over time, and were excellent in the effect of suppressing odor change. In addition, observation with an electron microscope confirmed that all formed a lipid bilayer. On the other hand, the comparative products 1 to 4 were not preferable as an external preparation for skin because generation of sulfur odor due to α-lipoic acid was observed over time.

Oil-in-water cream (ingredient) (%)
1. Hydrogenated soybean phospholipid 2.0
2. Cholesterol 2.0
3. Cetostearyl alcohol 3.0
4). Cholesteryl hydroxystearate 1.0
5). Vaseline 2.0
6). Squalane 4.0
7). Meadow Foam Oil 8.0
8). α-Lipoic acid 0.05
9. Dibutylhydroxytoluene 0.1
10. Methyl paraoxybenzoate 0.2
11.1,3-butylene glycol 10.0
12 Carboxyvinyl polymer 0.3
13. Purified water remaining amount 14. Sodium hydroxide 0.1
15. Arbutin 2.0
16. α-Glucosyl rutin 0.05

(Production method)
A: Heat and dissolve components (1) to (9) at 70 ° C.
B: Components (10) to (13) are heated and dissolved at 70 ° C.
C: While A is being stirred, B is gradually added to emulsify.
D: Cool C to room temperature.
E: (15) to (16) dissolved in a part of the component (13) were added to D and mixed uniformly to obtain an oil-in-water cream.

  The oil-in-water cream of Example 2 was a skin external preparation excellent in stability with no generation of sulfur odor over time.

Claims (5)

The following components (A) to (F);
(A) α-lipoic acid (B) phospholipid (C) cholesterol (D) one or two oil-soluble antioxidants selected from dibutylhydroxytoluene and tocopherol acetate (E) α-glucosylrutin, mica ) An external preparation for skin characterized by blending one or more water-soluble antioxidants (F) water selected from an extract and a merosria extract . Component (A) is blended in an amount of 0.001 to 1 mass%, and the blending mass ratio of component (A) / component (B) is 1/10 to 1/1000, and the blending mass ratio of component (B) / component (C). 1 / 0.1 to 1/1, the blending mass ratio of component (A) / component (D) is 1/1 to 1/100, and the blending mass ratio of component (A) / component (E) is 1 / The skin external preparation according to claim 1, which is 0.1 to 1/100 . The external preparation for skin according to claim 1 or 2 , wherein the external preparation for skin is liquid. The skin external preparation according to any one of claims 1 to 3 , wherein the skin external preparation is an oil-in-water type. The skin external preparation according to any one of claims 1 to 4 , wherein the component (A) is encapsulated in a lipid bilayer composed of the components (B) and (C).