JPH054910A - Cosmetic composition - Google Patents

Abstract

PURPOSE:To obtain a cosmetic composition, containing an alpha-amino acid derivative of thiohydantoin having a specific amino acid residue, having ultraviolet ray absorptivity exhibiting strong absorption within a long or medium wavelength region and improved in stability and safety. CONSTITUTION:A cosmetic composition containing at least one selected from alpha-amino acid derivatives (e.g. L-threonine thiohydantoin or L-tryptophan thiohydantoin) of thiohydantoin expressed by formula I (R is the L-, D- or DL- isomer of alpha-amino acid residue). The compound expressed by formula I is obtained by adding, e.g. an alpha-amino acid expressed by formula II and acetic anhydride into acetic acid solvent, heating the resultant solution, adding and reacting ammonium thiocyanate therewith, carrying out cyclization and then hydrolyzing the prepared compound. The aforementioned cosmetic composition is excellent in stability to irradiation with ultraviolet rays and safety for the skin.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel cosmetic composition, more specifically, a long wavelength region (320 to 400 nm) and / or a medium wavelength region (280 to 280 nm) depending on the type of amino acid residue.
The present invention relates to a cosmetic composition containing a thiohydantoin α-amino acid derivative having a strong ultraviolet absorption ability at 320 nm).

[0002]

BACKGROUND OF THE INVENTION There are many unclear points about the mechanism of pigmentation such as skin spots and freckles, but in general, melanin pigments are excessively produced due to hormonal abnormalities and irritation by ultraviolet rays, and It is thought to be abnormally deposited in the. As described above, ultraviolet rays are considered to be one of the causes of spots and freckles, and are known to cause various other damages to the skin. Therefore, in recent years, most cosmetics have been blended with an ultraviolet absorber as a skin protective agent to take measures against ultraviolet rays. As the ultraviolet absorber, conventionally, benzophenone-based, salicylic acid-based, cinnamic acid-based, p-aminobenzoic acid-based, benzotriazole-based compounds and the like have been used, but these compounds have been confirmed to have an ultraviolet absorbing effect. However, there are some that have problems in terms of safety to the skin, solubility in commonly used solvents, stability upon irradiation with ultraviolet rays, and the like. Salicylic acid-based UV absorbers, urocanic acid, and the like have relatively little irritation to the skin, but have a problem that they need to be blended in a high concentration because they have insufficient UV absorbing ability. In addition, most of the above-mentioned ultraviolet absorbers show maximum absorption mainly in the UVB region (280 to 320 nm), and show effective absorption in the UVA region (320 to 400 nm) which causes stains and freckles due to long-term exposure. Less is. In addition, there are some plant and animal tissue extracts that contain a component capable of absorbing ultraviolet rays, but many of them are not suitable for incorporation into cosmetics due to coloring, and the persistence of the ultraviolet absorbing effect is not always guaranteed. Not fully confirmed. On the other hand, dimethoxybenzalhydantoin derivatives (Japanese Patent Application Laid-Open No. 63-101371) and benzalhydantoin derivatives (Japanese Patent Application Laid-Open No. 63-101372) are used as hydantoin compounds having ultraviolet absorbing ability and useful for cosmetics.
However, no report has been made so far on the ultraviolet absorbing ability of amino acid derivatives of thiohydantoin.

[0003]

DISCLOSURE OF THE INVENTION The present invention is a cosmetic composition comprising a compound which exhibits strong absorption of ultraviolet rays in the UVB region and UVA region, and which is excellent in stability when exposed to ultraviolet rays and safety to the skin. It was made for the purpose of providing goods.

[0004]

As a result of intensive studies to develop a cosmetic composition having the above-mentioned characteristics, the present inventors have found that the α-amino acid derivative of thiohydantoin has different types of α-amino acid residues. Depending on UVB region and / or UVA
Based on this finding, the present invention has been completed based on the finding that it has an excellent ability to absorb ultraviolet light that exhibits strong absorption in a region, and is excellent in stability upon irradiation with ultraviolet light and safety on the skin. That is, the present invention has the general formula

[0005]

[Chemical 2]

At least one selected from the α-amino acid derivatives of thiohydantoin represented by the formula (wherein R is L-form, D-form or DL-form α-amino acid residue) The present invention provides a cosmetic composition comprising Hereinafter, the present invention will be described in detail. In the cosmetic composition of the present invention, the α-amino acid derivative of thiohydantoin represented by the general formula (1) is used as a compound having an ultraviolet absorbing ability. R in the general formula (1) is α-
An amino acid residue, that is, a residue excluding the α-aminoacetic acid group of an amino acid, which may be L-form, D-form or DL-form. The method for producing the α-amino acid derivative of thiohydantoin represented by the general formula (1) is not particularly limited, and a known method can be used. For example, the general formula

[0007]

[Chemical 3]

The α-amino acid represented by the formula (wherein R has the same meaning as described above) and acetic anhydride are added to an acetic acid solvent and heated, and ammonium thiocyanate is added thereto to cause a reaction. After the reaction, the α-amino acid derivative of thiohydantoin represented by the general formula (1) can be produced by hydrolysis.

Examples of the α-amino acid represented by the general formula (2) include glycine, alanine, valine, leucine, isoleucine, aspartic acid, glutamic acid, lysine, arginine, phenylalanine, tyrosine, cysteine, cystine, methionine, serine. , Threonine,
Tryptophan, histidine, proline and the like can be mentioned, and these α-amino acids may be L-forms,
The D-form may be used, or the racemic form may be used.

As examples of the α-amino acid derivative of thiohydantoin represented by the above general formula (1), thiohydantoin derivatives of L-threonine, L-isoleucine, DL-methionine and L-tryptophan can be mentioned. External absorption spectra are shown in FIGS. 1, 2, 3 and 4, respectively. Table 1 shows a comparison of the absorbances of these thiohydantoin derivatives and the conventionally well-used ultraviolet absorbers in the UVA region and the UVB region.

[0011]

[Table 1]

From Table 1, L-threonine thiohydantoin exhibits strong absorption in the UVA region and weak absorption in the UVB region, while L-tryptophan thiohydantoin,
It can be seen that L-isoleucine thiohydantoin and DL-methionine thiohydantoin each exhibit strong absorption in the UVB region. That is, the α-amino acid derivative of thiohydantoin according to the present invention has an ultraviolet absorptivity showing strong absorption in the UVA region and / or UVB region depending on the type of amino acid residue. Furthermore, the α-amino acid derivative of thiohydantoin has good stability to light and heat, and is excellent in safety to the skin, and also traps singlet oxygen by the thiocarbonyl group in the molecule,
It can be expected to have the effect of suppressing the peroxidation reaction caused by ultraviolet irradiation or the effect of removing the generated peroxide.

Therefore, among the α-amino acid derivatives of thiohydantoin, one having absorption in both the UVA region and UVB region is used alone, or one having absorption in the UVA region and one having absorption in the UVB region. By combining the above with a cosmetic composition, it is possible to obtain the cosmetic composition of the present invention which absorbs both ultraviolet rays in the UVA region and the UVB region and has a long-lasting effect. Such a cosmetic composition of the present invention can protect the skin from the damage of ultraviolet rays, prevent the aging of the skin due to the production of lipid peroxide, and can also be expected to have the whitening effect of sulfur.

In the cosmetic composition of the present invention, the α-amino acid derivative of thiohydantoin represented by the general formula (1) may be used alone or in combination of two or more, The content is usually selected in the range of 0.1 to 4% by weight, preferably 0.2 to 1% by weight, based on the total amount of the composition, though it depends on the product form and the frequency of use. In the composition of the present invention, if desired, various components usually used in cosmetic compositions, such as oil, water, and surfactants, moisturizers, lower alcohols, thickeners, antioxidants, Chelating agents, pH adjusters, preservatives, fragrances, dyes, other UV absorbers, UV scattering agents, vitamins, amino acids and the like can be added.

Examples of the oil include oils and fats such as olive oil, jojoba oil, cocoa butter, camellia oil, coconut oil, wax, crepe seed oil, avocado oil, mink oil, egg yolk oil, hardened oil, whale wax and honey. Wax, lanolin, carnauba wax,
Waxes such as candelilla wax, hydrocarbons such as liquid paraffin, ceresin, squalane, microcrystalline wax, paraffin wax and petrolatum, fatty acids such as stearic acid, oleic acid, lauric acid, myristic acid, isostearic acid and behenic acid , Cetanol, stearyl alcohol, lanolyl alcohol, octyldodecanol, hexyldecanol, and other alcohols, isopropyl myristate, butyl stearate, isopropyl palmitate, octyldodecyl myristate, octyldodecyl oleate, cholesterol oleate, and other esters. Can be mentioned.

Examples of the surfactant include anionic surfactants such as sodium stearate, sodium cetyl sulfate, polyoxyethylene lauryl ether phosphoric acid, sodium lauryl phosphate, triethanol palmitate, sodium N-acyl glutamate, and chlorides. Cationic surfactants such as stearyl dimethyl benzyl ammonium, stearyl trimethyl ammonium chloride,
Alkylaminoethylglycine hydrochloride liquid, amphoteric surfactant such as lecithin, glycerin monostearate, sorbitan monostearate, sucrose fatty acid ester, propylene glycol monostearate, polyoxyethylene oleyl ether, polyethylene glycol monostearate, monopalmitin Examples thereof include nonionic surfactants such as acid polyoxyethylene sorbitan, polyoxyethylene coconut fatty acid monoethanolamide, polyoxyethylene polyoxypropylene glycol, polyoxyethylene castor oil, and polyoxyethylene lanolin.

Examples of moisturizing agents include glycerin, 1,
Polyhydric alcohols such as 3-butylene glycol, propylene glycol, sorbitol, polyethylene glycol and dipropylene glycol, amino acids, NMF components such as sodium lactate and sodium pyrrolidonecarboxylate, water-soluble such as hyaluronic acid, collagen, mucopolysaccharides and chondroitin sulfate. Polymeric substances and the like, lower alcohols such as ethanol and isopropanol, and thickeners such as sodium alginate,
Natural polymer such as xanthan gum, aluminum silicate, malome seed extract, tragacanth gum, starch, methyl cellulose, hydroxyethyl cellulose,
Examples thereof include semi-synthetic polymeric substances such as carboxymethyl cellulose, soluble starch, cationized cellulose, synthetic polymeric substances such as carboxyvinyl polymer and polyvinyl alcohol.

The antioxidants include, for example, dibutylhydroxytoluene, butylhydroxyanisole,
Propyl gallate, ascorbic acid and the like, as the chelating agent, for example, disodium edetate, ethanehydroxydiphosphate, pyrophosphate, hexametaphosphate, citric acid, tartaric acid, gluconic acid, etc., as the pH adjusting agent, for example. Sodium hydroxide, triethanolamine, citric acid, sodium citrate, boric acid, borax,
Examples of preservatives such as sodium monohydrogen phosphate include methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, dehydroacetic acid, salicylic acid, benzoic acid, sorbic acid, and benzalkonium chloride.

Further, other ultraviolet absorbers include, for example, 2-hydroxy-4-methoxybenzophenone, octyldimethyl p-aminobenzoate, ethylhexyl p-methoxycinnamate, and the like, and ultraviolet diffusers include, for example, titanium oxide and kaolin. , Talc and the like include vitamins such as vitamin A, vitamin B, vitamin C, vitamin D, vitamin E, vitamin F, vitamin K, vitamin P, vitamin U, carnitine, ferulic acid, γ-oryzanol and α-lipo. Acid, orotic acid and derivatives thereof, and the like, as amino acids, for example, glycine, alanine, valine, leucine, isoleucine, serine, threonine, phenylalanine, tyrosine, tryptophan, cystine, cysteine, methionine, proline, hydroxyprolyl. And aspartic acid, glutamic acid, arginine, histidine, lysine and their derivatives. The optional components are not limited to these. The cosmetic composition of the present invention, for example, lotion, cream, pack, lotion, skin milk, by appropriately blending the essential components of the α-amino acid derivative of thiohydantoin and these optional components,
It can be used in various product forms such as emulsion, liquid foundation, and aerosol cosmetics.

[0020]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto. Production Example 1 Production of L-threonine thiohydantoin 0.01 mol (1.19 g) of L-threonine was placed in a reaction vessel, and acetic anhydride (10.2 ml) and acetic acid (1.0 ml) were sequentially added thereto at 80 ° C.
Heat up to and stir until uniform. Furthermore, 0.01 mol (0.76 g) of ammonium thiocyanate was added,
React on a warm water bath (45-50 ° C.) for 2 hours. At this time, the solution is pale yellow to dark orange. Then, the solvent was completely distilled off with an evaporator, 6 ml of 6N-HCl (2.0 ml) was added, and the mixture was left standing on a warm water bath (45-50 ° C.) for 3 hours. After standing, hydrochloric acid was distilled off with an evaporator, an appropriate amount of purified water was added, and filtration and washing were carried out to obtain L-threonine thiohydantoin (95% active ingredient). The molecular absorbances of the thus-obtained L-threonine thiohydantoin at wavelengths 320 to 325 nm and 275 to 285 nm were determined to be 2.1 × 10 ⁴ and 1.
It was 2 × 10 ⁴ . The ultraviolet absorption spectrum is shown in FIG.

Production Examples 2 to 4 L-isoleucine as an amino acid (Production Example 2), DL-
Using methionine (Production Example 3) and L-tryptophan (Production Example 4), L-isoleucine thiohydantoin, DL-methionine thiohydantoin and L-tryptophan thiohydantoin were produced in the same manner as in Production Example 1. The molecular absorbances of these α-amino acid thiohydantoins at wavelengths 320 to 325 nm and 275 to 285 nm were determined. The results are shown in Table 2. Also, L-
The ultraviolet absorption spectrum of isoleucine thiohydantoin is shown in FIG. 2, that of DL-methionine thiohydantoin is shown in FIG. 3, and that of L-tryptophan thiohydantoin is shown in FIG.

[0022]

[Table 2]

Example 1 Preparation of Cream A cream having the following composition was prepared. L-threonine thiohydantoin of Production Example 0.5 wt% stearic acid 6.0 wt% glycerin monostearate 2.5 wt% sericin 3.8 wt% white petrolatum 12.0 wt% liquid petrolatum 3.2 wt% propylene glycol 6.4 wt% Triethanolamine 1.9wt% Methylparaben 0.1wt% Glycyrrhizin dipotassium 0.1wt% Perfume Trace amount Purified water Balance

Example 2 Preparation of emulsion A. Oil phase Liquid paraffin (# 100) 10.0 wt% L-threonine thiohydantoin of Production Example 1 0.25 wt% DL-methionine thiohydantoin of Production Example 3 0.25 wt% Isopropyl myristate 3.0 wt% Glycerin monostearate 0.5 wt% stearic acid 2.0wt% POE (20) stearyl ether 0.7 wt% glycyrrhizic acid 0.08 wt% butyl paraben 0.1 wt% B. Water phase Glycerin 3.0 wt% Carbopol 941 0.2 wt% Ethanol 9.0 wt% Purified water balance C.I. Fragrance Amount The above-mentioned formulations A and B were mixed and dissolved at 70 ° C., and then A was added to B and emulsified uniformly. Further, C was added and cooled to prepare an emulsion. Using the cream of the formulation of Example-1, the Japan Cosmetic Industry Association SPF measurement standard proposal (3
Each SPF value was measured according to Cosmetic Engineering Association No. 11).
However, sunlight in July was used as a light source, and the subjects were 10 healthy men in their 20s. The following numerical values are average values of the SPF value of each person. Sample cream SPF L-isoleucine thiohydantoin combination cream 6 L-methionine thiohydantoin combination cream 6 L-threonine thiohydantoin combination cream 9

From the above results, it can be seen that the amino acid thiohydantoin exhibits an effective protective effect against the effects of UVA and UVB on the skin. Here, SPF was measured by the following method. 1. Selection of test subjects and test sites (1) The test subjects are healthy men and women over the age of 18 who fall under the following skin type classifications (a) to (c). However, this excludes those who have been interviewed and have photosensitivity or who are taking drugs (anti-inflammatory agents, antihypertensive agents, etc.) that are involved in skin photosensitivity. Skin type (a) Very easy to get sunburned (reddish), but never blackened. (B) Sunburn (turns red) easily and turns slightly black. (C) It always turns black after sunburn (turns red). (D) It does not tan much (turns red), but turns black immediately. (E) It rarely tans (turns red), but becomes very black. (F) Never get a sunburn (turn red), it becomes very black. Based on the skin reaction after sun-bathing for 30-45 minutes from spring to summer. (2) The test site shall be the back, and the skin shall have almost uniform skin color without pigmentation or nevus. 2. The number of subjects is 10 or more. However, the standard error in SPF measurement should not exceed 10% of the obtained SPF value. 3. Preparation of standard sample A standard sample A is prepared, and this is carried out at the same time as the measurement of the test sample to confirm the validity of the judgment standard of the test sample. The prescription of the standard sample A is as follows. Standard sample A 8% homomenthyl salicylate-containing preparation (equivalent to SPF4) Aa part Lanolin (cosmetic base) 5.00% by weight Homomenthyl salicylate (extra cosmetics standard) 8.00% by weight Vaseline (cosmetic base) 2.50% by weight stearin Acid (Cosmetic base) 4.00% by weight Propyl paraoxybenzoate (Cosmetic base) 0.05% by weight Ab part Methyl paraoxybenzoate (Cosmetic base) 0.10% by weight Disodium edetate (Cosmetic base) 0.1% 05% by weight Propylene glycol (cosmetic base) 5.00% by weight Triethanolamine (cosmetic base) 1.00% by weight Purified water (cosmetic base) 74.30% by weight The parts are heated to 82 ° C. to dissolve each component. Then, while stirring, the A-a part is poured into the A-b part. Continue stirring until the emulsification formed cools to room temperature. The weight is corrected by adding purified water so that the standard sample becomes 100 wt%.

4. Sample application amount The sample application amount is 2 mg / cm ² or 2 μl / cm ² . 5. Sample application area The sample application area should be 20 cm ² or more. 6. Time from application of sample to irradiation The time from the end of application of the sample to the start of irradiation is 15 minutes or more. 7. Light source The light source uses a xenon arc solar simulator,
It must meet the following conditions: (1) The emitted ultraviolet rays in the UVB range have wavelengths of 290 to 290.
It should be a continuous spectrum similar to sunlight at 320 nm. (2) Ultraviolet rays with a wavelength of 290 nm or less should be removed as much as possible using an appropriate filter. In addition, maintenance and inspection must be performed so that the above conditions are always satisfied. 8. Irradiation field 1 Irradiation field should be 0.5 cm ² or more. 9. Range of irradiation increase The amount of irradiation is proportionally increased, and the ratio is 25% at maximum. 10. MED (Minimal Erythema D)
ose: Minimum erythema dose) MED is the minimum amount of ultraviolet rays at which a slight erythema is observed in almost the entire irradiation field 16 to 24 hours after irradiation. M
The ED is determined in a sufficiently bright room 16 to 24 hours after the end of irradiation. In addition, it is desirable that a plurality of experts perform the determination. 11. Calculation method of SPF value The SPF value is calculated according to the following equation using the MED obtained in the sample non-coated portion and the sample coated portion. SPF value = MED of sample application part / MED of sample non-application part The arithmetic mean value of the SPF value of each subject thus obtained is taken as the SPF value of this sample. The average value is rounded down after the decimal point, and the SPF value is expressed as an integer. Next, examples of experiments in which these ultraviolet absorbers are incorporated into hair care products will be shown.

Example 3 Preparation of Rinse Agent (No. 1) A rinse agent having the following composition was prepared. Isoleucine thiohydantoin of Production Example 2 0.1 wt% Stearyl trimethyl ammonium chloride 2.0 wt% Cetanol 3.2 wt% Glycerine monostearate 0.4 wt% Cyclic silicone 1.0 wt% Methylparaben 0.1 wt% Disodium edetate 0.1 wt % Fragrance Fractional Purified Water Balance

Example 4 Preparation of Rinse Agent (No. 2) A rinse agent having the following composition was prepared. DL-methionine hydantoin of Production Example 0.1 0.1 wt% stearyltrimethylammonium chloride 4.0 wt% stearyl dimethylaminoacetic acid betaine 1.0 wt% polyoxyethylene oleyl ethether 1.0 wt% cetostearyl alcohol 2.8 wt% glycerin monostearate 1.0wt% Methylparaben 0.1wt% Disodium edetate 0.1wt% Perfume Trace amount Purified water Balance

Example 5 Preparation of Conditioning Agent The following conditioning agent was prepared. L-threonine thiohydantoin of Production Example 1 0.1 wt% L-isoleucine thiohydantoin of Production Example 2 0.1 wt% Octyldodecanol 2.0 wt% Stearyl trimethyl ammonium chloride 4.0 wt% Stearyl dimethylamino acetic acid betaine 1.0 wt% Polyoxyethylene oleyl ether 1.0 wt% Cyclic silicone 1.0 wt% Cetostearyl alcohol 3.0 wt% Lanolin 2.0 wt% Glycerin monostearate 1.0 wt% Methylparaben 0.1 wt% Disodium edetate 0.1 wt% Perfume Trace amount Purified water balance

An appropriate amount of the rinse agent or the conditioning agent prepared in Example 3, Example 4 and Example 5 was applied to the hair after shampoo washing, and then lightly rinsed,
An electron micrograph of the hair surface was taken after the operation of irradiating with ultraviolet rays (UVA and UVB) at 30 J / cm ² (for one day in fine weather) was repeated 7 times in succession. FIGS. 5, 6 and 7 are reproductions of electron micrographs of the hair of Examples 3, 4 and 5 after the ultraviolet irradiation test. FIG. 8 is a copy of an electron micrograph of hair that has not been irradiated with ultraviolet rays, and FIG. 9 shows the same after irradiation with ultraviolet rays as described above using a rinse agent containing no ultraviolet absorber. It is a copy figure of the electron micrograph of hair.

In FIG. 9, severe curling and cracking of the cuticles 1 to 6 in the figure are observed. In the actual photograph, the cracks of the cuticles 1 and 2 (the cuticles have a white shining and the cracks in the shadows thereof appear as black grooves) are particularly large, and the cuticles are also small in areas other than 1 to 6. Disturbances are observed in a few places. In the case of using the rinse or conditioner to which the ultraviolet absorber of the present invention is added, there is a small disturbance of the cuticle as shown in a, b, c of FIG. In 7, there is almost no cuticle disorder,
Little difference from the unirradiated hair of Figure 8 is observed.

[0032]

EFFECTS OF THE INVENTION According to the above-mentioned examples, by properly selecting one or more kinds from α-amino acid derivatives of thiohydantoin and blending them into a cosmetic composition, it is possible to effectively absorb ultraviolet rays in the UVA region and the UVB region. It is possible to obtain a cosmetic composition which is capable of having a long-lasting effect. The cosmetic composition of the present invention is effectively treated to suppress damage and yellowing of hair by treating with the hair rinse and conditioning agents containing the amino acid thiohydantoin shown in Examples 3, 4, and 5, for example. be able to. Also,
By applying the amino acid thiohydantoin-containing skin cream on the skin surface, the UVA region and the UVB region are effectively shielded, the skin is protected from the damage of ultraviolet rays, and the skin aging due to lipid peroxide formation is prevented, and further sulfur is added. It is possible to exhibit excellent characteristics such as the effect of whitening the skin can be expected.

[0033]

[Brief description of drawings]

FIG. 1 shows L-threonine thiohydantoin, L
FIG. 3 is an ultraviolet absorption spectrum diagram of isoleucine thiohydantoin, DL-methionine thiohydantoin and L-tryptophan thiohydantoin.

[0034]

FIG. 2 shows L-threonine thiohydantoin, L
FIG. 3 is an ultraviolet absorption spectrum diagram of isoleucine thiohydantoin, DL-methionine thiohydantoin and L-tryptophan thiohydantoin.

[0035]

FIG. 3 shows L-threonine thiohydantoin, L
FIG. 3 is an ultraviolet absorption spectrum diagram of isoleucine thiohydantoin, DL-methionine thiohydantoin and L-tryptophan thiohydantoin.

[0036]

FIG. 4 shows L-threonine thiohydantoin, L
FIG. 3 is an ultraviolet absorption spectrum diagram of isoleucine thiohydantoin, DL-methionine thiohydantoin and L-tryptophan thiohydantoin.

[0037]

FIG. 5 is a copy of an electron micrograph of hair after the ultraviolet irradiation test of Examples 3, 4, and 5.

[0038]

FIG. 6 is a copy of an electron micrograph of hair after the ultraviolet irradiation test of Examples 3, 4, and 5.

[0039]

FIG. 7 is an electron micrograph of hair of Examples 3, 4, and 5 after the ultraviolet irradiation test.

[0040]

FIG. 8 is a copy of an electron micrograph of hair before the irradiation test.

[0041]

FIG. 9 is a copy of an electron micrograph of the hair of Example 3 after the ultraviolet irradiation test, which was performed on the hair treated with the rinse not containing the ultraviolet absorbent of the present invention.

[0042]

[Explanation of symbols]

 a, b, and c are disordered parts of the cuticle 1-6 are disordered parts of the cuticle

Claims (1)

What is claimed is: 1. A general formula: (Wherein R is an L-form, D-form or DL-form α-amino acid residue) and contains at least one selected from α-amino acid derivatives of thiohydantoin. Cosmetic composition.