JPH0632714A - External preparation for skin - Google Patents

Abstract

PURPOSE:To obtain an external preparation for skin remarkably improved in stability of vitamin A and/or its fatty acid ester. CONSTITUTION:This external preparation for skin is obtained by blending vitamin A and/or its fatty acid ester with (A) one or two or more kinds of lipophilic antioxidants selected from a group consisting of butylhydroxytoluene, butylhydroxyanisol, alpha,beta,gamma,delta-tocopherol, nordihydroguaiaretic acid, propyl gallate and vitamin C fatty acid esters, (B) one or two kinds of ascorbic acid, ascorbic acid salts, isoascorbic acid, isoascorbic acid salts, sorbic acid and sorbic acid salts and (C) one or two or more kinds of benzophenone based compounds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external preparation for skin in which the stability of vitamin A and / or its fatty acid ester is remarkably improved.

[0002]

2. Description of the Related Art Vitamin A and / or its fatty acid ester is known to be an effective component for the prevention and treatment of cutaneous keratoses and the prevention and recovery of skin aging.

However, vitamin A and / or its fatty acid ester is structurally extremely unstable, and light,
Since various isomerizations, decompositions, polymerizations, etc. are easily caused by air, heat, metal ions, etc., it has been difficult to stably compound them in the skin external preparation.

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive studies in view of such circumstances, the present inventors have found that (A) butylhydroxytoluene (hereinafter abbreviated as BHT) and butylhydroxy together with vitamin A and / or its fatty acid ester. One or two oil-soluble antioxidants selected from the group consisting of anisole (hereinafter abbreviated as BHA), α, β, γ, δ-tocopherol, nordihydroguaiaretin, propyl gallate, and vitamin C fatty acid ester. With seeds or more, (B)
If ascorbic acid, ascorbic acid salt, isoascorbic acid, isoascorbic acid salt, sorbic acid, one or more kinds of sorbic acid salts, and (C) one or more kinds of benzophenone compounds are mixed, vitamin A and / or Further, they have found that the stability of the fatty acid ester is remarkably improved, and completed the present invention.

[0005]

That is, the gist of the present invention is to provide vitamin A and / or a fatty acid ester thereof, and
(A) Butylhydroxytoluene (hereinafter abbreviated as BHT), butylhydroxyanisole (hereinafter abbreviated as BHA), α, β, γ, δ-tocopherol, nordihydroguaiaretin, propyl gallate, and vitamin C fatty acid. One or more oil-soluble antioxidants selected from the group consisting of esters, and (B) one or two of ascorbic acid, ascorbate, isoascorbic acid, isoascorbate, sorbic acid, sorbate. Over seeds,
(C) one or more benzophenone compounds,
It exists in the external preparation for skin characterized by being compounded.

The structure of the present invention will be described in detail below.

Vitamin A and / or used in the present invention
Alternatively, examples of the fatty acid ester thereof include vitamin A (also known as retinol), vitamin A acetate (also known as retinol acetate), and vitamin A palmitate (also known as retinol palmitate), all-trans type or 13-cis. It is preferably a mold and may be a mixture thereof. Further included are fatty oils obtained from fresh aquatic animals liver and pyloric appendix, and concentrates thereof.

There is no particular limitation on the amount to be added to the skin external preparation according to the present invention, but considering the effect of vitamin A on the skin, it is 0.0001% by weight or more, and the effect of vitamin A is strongly appealed. In order to
It is 1% by weight or more. The upper limit of the compounding ratio is preferably 10% by weight in view of the property as an external preparation for skin.

Oil-soluble antioxidants to be added to the external preparation for skin according to the present invention include BHT, BHA, α, β, γ,
δ-tocopherols, nordihydroguaiaretin, propyl gallate, vitamin C fatty acid ester and the like are exemplified.

The amount applied to the present invention is 0.001
It is preferably at least wt%, more preferably at least 0.01 wt%. In order to exert the effects of the invention for a longer period, 0.03% by weight is preferable. The upper limit of blending differs depending on the dosage form of the external preparation for skin and cannot be limited because it can be arbitrarily blended, but it is preferably 10% by weight in view of the properties as an external preparation for skin.

Ascorbic acid (also known as vitamin C), isoascorbic acid (also known as erythorbic acid), sorbic acid and salts thereof used in the present invention include inorganic alkali salts such as sodium salt and potassium salt, and ethanolamine. Examples thereof include organic alkali salts of basic compounds and basic amino acids. Among them, ascorbic acid, sodium ascorbate, isoascorbic acid (also called erythorbic acid), sodium isoascorbate (also called erythorbate sodium), sorbic acid, sodium sorbate, and potassium sorbate are preferable. It is also possible to form a salt in the system by using each acid and basic substance in combination.

The amount blended in the present invention is 0.00
It is 1% by weight or more, and the upper limit of blending is not particularly limited. However, when blended in an extremely large amount, the effect of the present invention is not impaired, but the quality as a skin external preparation can be maintained due to precipitation of crystals and the like. Disappear. It is preferably 10% by weight or less.

The benzophenone-based compounds used in the present invention include 2,4-dihydroxybenzophenone (hereinafter benzophenone-1), 2,2 ', 4,4'-tetrahydroxybenzophenone (hereinafter benzophenone-2),
2-hydroxy-4-methoxybenzophenone (hereinafter benzophenone-3), 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (hereinafter benzophenone-)
4), 2-hydroxy-4-methoxybenzophenone-
Sodium 5-sulfonate (hereinafter benzophenone-
5), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone (hereinafter benzophenone-6), 2-hydroxy-5-chlorobenzophenone (hereinafter benzophenone-7), 2,2'-dihydroxy-4-methoxybenzophenone (Hereinafter benzophenone-8), 2,2'-dihydroxy-4,4'-dimethoxybenzophenone-
5,5'-Disodium disodium salt (hereinafter benzophenone-9), 2-hydroxy-4-methoxy-4'methylbenzophenone (hereinafter benzophenone-10), 2-
Examples thereof include hydroxy-4-octyloxybenzophenone (hereinafter benzophenone-12).

The content of the external preparation for skin of the present invention is 0.001% by weight or more, and the upper limit of the content is not particularly limited, but the effect of the present invention is impaired when the content is extremely large. Although it is not a substance, the quality as an external preparation for skin cannot be maintained due to the precipitation of crystals. Preferably 1
It is 0% by weight or less.

In the external preparation for skin of the present invention, in addition to the above-mentioned essential components, other components usually used in cosmetics and quasi drugs, such as moisturizers, surfactants, preservatives, water, alcohols, thickeners, -Oil, a drug, a chelating agent, a fragrance, a coloring agent, an ultraviolet absorber, and the like can be added, if necessary, within a range that does not impair the effects of the present invention.

[0016]

EXAMPLES The present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention.

[0017]

[Table 1]

In Examples 1 and 2, the stability of retinol acetate was improved as compared with Comparative Example, which is an effect according to the present invention.

Production methods of Examples 1 and 2 and Comparative Examples 1 and 2
Temperature test method BHT, tocopherol, benzophenone, and octyl methoxycinnamate are completely dissolved in each oil component at 60 ° C., then sorbic acid and dipropylene glycol are dissolved in ethyl alcohol, and the mixture is cooled to 40 ° C. After that, retinol acetate is completely dissolved, sealed in a brown glass sample tube, further wrapped with aluminum foil to be completely shielded from light, and stored in a constant temperature bath at 40 ° C.

Quantitative Method for Retinol Acetate The Japanese Pharmacopoeia (11th revision) Vitamin A Quantitative Method According to the first method, quantitative determination was carried out by an absorbance measuring method using isopropanol.

[0021]

[Table 2]

In Examples 3 and 4, the stability of retinol was improved as compared with Comparative Example, which is an effect according to the present invention.

The manufacturing method of Examples 3 and 4 and Comparative Examples 3 and 4
Temperature test method BHT, tocopherol and benzophenone-2 are completely dissolved in each oil and surfactant at 70 ° C., and then retinol is completely dissolved immediately before emulsification to obtain an oil phase. -Glycerin, propylene glycol, carboxyvinyl polymer, caustic potash, ascorbic acid and benzophenone-
5 is completely dissolved in purified water, the oil phase is added to the aqueous phase heated to 70 ° C., and the mixture is emulsified by a homomixer type emulsifier. Next, a heat exchanger is used to cool the mixture to 30 ° C. to obtain an emulsion. The emulsion is filled in a metal-coated glass bottle, sealed, and stored in a constant temperature bath at 40 ° C.

Retinol Quantitative Method It was measured by an absorbance measuring method at 325 nm using ethanol. Samples were prepared by removing retinol from the examples and comparative examples, and the absorption at 325 nm was measured and corrected as the absorbance of the base. (Absorbance at 325 nm of samples of Examples and Comparative Examples)-(Absorbance of withdrawn product) = Absorbance of retinol Absorption maximum 325 nm, E (1%, 1)
cm) = 1835.

Example 5 Lotion (wt%) Oleyl alcohol 0.002 Benzophenone-12 0.001 α-tocopherol 0.001 Retinol acetate 0.0001 POE (50) oleyl ether 0.7 Lactic acid 0.1 Sodium lactate 0 .9 ethanol 8 glycerin 2 methylparaben 0.2 sodium erythorbate (sodium isoascorbate) 0.5 purified water

Example 6 Oil Essence (% by Weight) 2-Ethylhexanoic Acid Triglyceride 10 Octyldodecanol 20 Squalane 32 BHT 1 α-Tocopherol 9 Retinol Acetate 8 Retinol Palmitate 2 Dipropylene Glycol 12.89 Ethyl Alcohol 5 Benzophenone-6 0.1 sorbic acid 0.01

Example 7 Cream (wt%) Squalane 15 2-Ethylhexanoic Acid Triglyceride 8 Isopropylmyristate 7 BHT 0.05 BHA 0.01 α-Tocopherol 0.01 Retinol 0.3 Vaseline 2 Butylparaben 0.1 Propyl Paraben 0.1 Oleic acid monoglyceride 3 Diglycerin diisostearate 2 PEG400 Dioleate 1 Glycerin 10 Dipropylene glycol 5 Sodium ascorbate 0.01 Benzophenone-8 0.1 Benzophenone-4 0.03 Triethanolamine 0.04 Purified water Amount of 100 as a whole

Example 8 Beauty Essence (% by Weight) Glycerin 30 Propylene Glycol 10 Olive Oil 2 BHT 0.1 α-Tocopherol 0.1 Retinol Acetate 0.1 Ethyl Alcohol 4 Ascorbic Acid 10 Potassium Sorbate 0.1 Xanthan Gum 0.8 POE (60) hydrogenated castor oil 0.6 purified water 100

Example 9 Oil Gel (wt%) 2-Ethylhexanoic Acid Triglyceride 60 POE (20) Octyldodecyl Ether 16 Retinol 0.1 Benzophenone-12 0.1 Glycerin 16 Erysorbic Acid (Isoascorbic Acid) 0.05 Benzophenone -5 0.05 BHA 0.01 BHT 0.01 Purified water 100 amount

The skin external preparations of Examples 5 to 9 were excellent in stability of vitamin A and / or its fatty acid ester in daily use.

[0031]

In the external preparation for skin of the present invention, (A) butylhydroxytoluene (hereinafter abbreviated as BHT), butylhydroxyanisole (hereinafter abbreviated as BHA),
One or more oil-soluble antioxidants selected from the group consisting of α, β, γ, δ-tocopherol, nordihydroguaiaretin, propyl gallate, and vitamin C fatty acid ester, (B) ascorbic acid, ascorbic acid Vitamin A and / or its fatty acid ester by blending one or more kinds of salt, isoascorbic acid, isoascorbate, sorbic acid, sorbate, and (C) one or more kinds of benzophenone compounds The stability of can be significantly improved.

Claims (1)

[Claims] 1. A (A) butylhydroxytoluene (hereinafter abbreviated as BHT), butylhydroxyanisole (hereinafter abbreviated as BHA), α, together with one or more kinds of vitamin A and / or its fatty acid ester. β,
γ, δ-tocopherol, nordihydroguaiaretin,
One or more oil-soluble antioxidants selected from the group consisting of propyl gallate and vitamin C fatty acid ester, (B) ascorbic acid, ascorbate, isoascorbic acid, isoascorbate, sorbic acid, sorbin An external preparation for skin, comprising one or more acid salts and one or more benzophenone compounds (C).