JPH06219931A - Ultraviolet protecting cosmetic - Google Patents

Abstract

PURPOSE:To obtain an ultraviolet protecting cosmetic capable of providing ultraviolet protecting action on skin without changing color tone of skin. CONSTITUTION:The ultraviolet W-projection cosmetic contains 0.1-5wt.% dihydroxyacetone and 0.1-10wt.% tryptophan based on total amount of cosmetic or the cosmetic consists of the first cosmetic containing dihydroxyacetone and the second cosmetic containing tryptophan and dihydroxyacetone content in the first cosmetic is 0.1-5wt.% and tryptophan content in the second cosmetic is 0.1-10wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a UV protective cosmetic composition, and more specifically, to a UV protective cosmetic composition having excellent abrasion resistance which forms a UV protective layer having excellent skin compatibility on or in the skin corneal layer. Regarding

[0002]

2. Description of the Related Art Conventionally, cosmetics containing UV absorbers, UV scatterers, etc. have been used to prevent sunburn. When such a cosmetic is applied to the skin, ultraviolet rays can be absorbed and scattered on the skin surface to prevent sunburn.

Further, it has been reported that the combined use of dihydroxyacetone and Lawson, which is a kind of dye, has an effect of absorbing ultraviolet rays and visible rays in the short wavelength region in the stratum corneum of the skin (Fragrance Journal.
No. 43 (1980)), and a large number of reports showing effectiveness as a UV protection method especially for sun-sensitive patients (eg International Journal of Dermatology, 11, N).
o.2, (1972)). In addition, UV protection cosmetics (Dermatologica 148, 224-2) by the combination of dihydroxyacetone and Lawson (2-hydroxy-1,4-naphthoquinone)
27 (1974)) have been reported.

It should be noted that dihydroxyacetone itself is not known to have an ultraviolet protection effect such as an ultraviolet absorption effect.

[0005]

The conventional cosmetics using the above-mentioned ultraviolet absorber or ultraviolet scatterer have an ultraviolet ray-preventing effect immediately after being applied to the skin, but are easily removed by rubbing or washing with clothes or the like. Therefore, there is a problem that the durability of the ultraviolet ray protection effect is not good.

[0006] Further, the cosmetics in which dihydroxyacetone and lausone are used in combination can exert a certain sunscreen effect continuously, but at the same time, they have a tanning effect and strongly develop the skin in a yellow-red color. It is not preferable. Furthermore, there remain problems such as a small light absorption effect.

The present invention has been made from such a point of view, and in order to overcome the above-mentioned problems, it has excellent abrasion resistance, has a long-lasting ultraviolet ray preventive effect, and gives the skin an unfavorable skin color. It is an object to provide a UV protective cosmetic which is not colored.

[0008]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor has shown that when tryptophan is used in combination with dihydroxyacetone, it exhibits an ultraviolet absorbing effect in the UV-A region and further develops color. The present invention has been completed by finding that it is possible to exhibit a long-lasting and long-lasting UV protection effect.

That is, according to the present invention, the total amount of cosmetics is 0.
1-10 wt% dihydroxyacetone, 0.01-
An ultraviolet protective cosmetic composition containing 10% by weight of tryptophan. The present invention further includes a first cosmetic containing dihydroxyacetone and a second cosmetic containing tryptophan.
The content of dihydroxyacetone in the first cosmetic is 0.1 to 10% by weight, and the content of tryptophan in the second cosmetic is 0.0.
Provided is a UV protection cosmetic which is 1 to 10% by weight.

The present invention will be described in detail below. The UV protective cosmetic composition of the present invention comprises 0.1 to 10% by weight, preferably 0.5 to 2% by weight, of dihydroxyacetone and 0.01 to 10% by weight, preferably 0.5 to 5
Contains wt% tryptophan. If the content of dihydroxyacetone is less than this range, the effect of absorbing UV-A and the tanning effect cannot be expected, and if it is too large, it is not preferable for the safety of the skin. On the other hand, if the content of tryptophan is less than this range, the effect of absorbing UV-A is small, and if it is too large, it is difficult to dissolve and it is not preferable because it is sticky to the touch.

Although dihydroxyacetone and tryptophan may be blended in the cosmetic in advance, they may be divided into two agents because they are colored in the cosmetic. That is, it is divided into a first cosmetic material containing dihydroxyacetone and a second cosmetic material containing tryptophan, and these are mixed at the time of use,
Alternatively, it may be applied on the skin and used. Also in this case, the amounts of dihydroxyacetone and tryptophan should be within the above ranges with respect to the total amount of the first and second cosmetics combined.

Usually, amino acids such as lysine are present in the stratum corneum of skin, and these react with dihydroxyacetone to develop color. Therefore, when dihydroxyacetone alone is blended in a cosmetic composition, it has a tanning effect to some extent but no UV protection effect. The UV-A absorption effect is exhibited by using tryptophan together.

In addition to the above components, the cosmetic of the present invention contains various cosmetic bases and additives used in ordinary cosmetics,
For example, inorganic pigments, organic pigments, inorganic powders, organic powders, hydrocarbons, silicones, esters, triglycerides, lanolins, waxes, waxes, animal and vegetable oils, surfactants, polyhydric alcohols, etc. Bases and sugars, vitamins such as vitamin A, vitamin B group, vitamin E, amino acids, anti-inflammatory agents such as glycyrrhizin or glycyrrhetinic acid or derivatives thereof, antioxidants, preservatives, perfumes, thickeners, astringents Additives such as an agent, a cell activator, a whitening agent, a rough skin improving agent, and a conventionally used ultraviolet absorber and ultraviolet scattering agent can be added. However, since it reacts with tryptophan, it is preferable not to add excess fatty acid.

The dosage form of the cosmetic of the present invention is not particularly limited, and the cosmetic can be manufactured according to the usual manufacturing method of cosmetics.

[0015]

Next, the function of dihydroxyacetone and tryptophan used in the present invention will be described.

FIG. 1 shows absorption spectra of dihydroxyacetone, tryptophan and mixtures thereof.
The spectra were measured for the following samples using a spectrophotometer U-3500 manufactured by Hitachi Ltd. (A) 50 wt% ethanol aqueous solution containing 0.5 wt% tryptophan (B) 50 wt% ethanol aqueous solution containing 0.5 wt% dihydroxyacetone (C) 50 wt% ethanol containing 0.5 wt% both tryptophan and dihydroxyacetone Aqueous solution

The spectrum was measured by diluting the above sample with a 50% aqueous ethanol solution so that the concentration of tryptophan and / or dihydroxyacetone was 0.001% by weight.

As is clear from this result, the mixed solution of dihydroxyacetone and tryptophan contained 290 to 4
It is clear that it has a function of absorbing ultraviolet rays in the UV-A region of 20 nm. Also, as in the case of using dihydroxyacetone and Lawson in combination, no large absorption in the yellow-red band is observed.

On the basis of the above-mentioned actions, the UV-protective cosmetic composition of the present invention in which dihydroxyacetone and tryptophan are used in combination has a UV-absorbing action in the UV-A region and does not cause the skin to have an undesired skin color.

[0020]

EXAMPLES Examples of the present invention will be described below. In addition, the following compounding amounts are% by weight.

[0021]

[Example 1] As an ultraviolet protective cosmetic of the present invention, an example in an emulsion and its sustaining effect will be described.

<Production Method> Ingredients A and B in Table 1 are dissolved at 70 ° C. with stirring. The component A is added to the component B to carry out preliminary emulsification, and the mixture is uniformly emulsified with a homomixer and then cooled to 50 ° C. with stirring. To this emulsion, the component C heated and kept at 50 ° C. is added with stirring, and the mixture is cooled with stirring until it reaches 30 ° C.

In this way, an emulsion (1) containing tryptophan, an emulsion (3) containing dihydroxyacetone, and an emulsion (2) containing neither were produced.

[0024]

[Table 1]

<Change in Skin Color with UV-Protective Cosmetic of the Present Invention> The change in skin color due to the use of the emulsion obtained in the above Production Example was examined. As an example, after applying the milky lotion containing tryptophan (1) to the lower arm of the subject, 15 minutes later, the milky lotion containing dihydroxyacetone (3) was applied, and the skin color was measured over time. It was

Similarly as a comparative example, the emulsion (3) was applied 15 minutes after the application of the emulsion (2) containing neither tryptophan nor dihydroxyacetone, and the skin color was measured over time.

The skin color is measured by a colorimeter (CMS-1200 manufactured by Murakami Color Research Institute) by a method of L *, a *, b * color measurement (International Commission on Illumination (CIE) (1976)). Done,
The whiteness (w) was calculated by the following formula. In this test, the lower the whiteness value, the higher the tanning effect.

Whiteness (W) = 100-{(100-L *) ²
+ A * ² + b * ² )} ^1/2 The results of colorimetry are shown in Table 2.

[0029]

[Table 2]

As shown in these results, the use of the UV protective cosmetic composition of the present invention reduced the whiteness value (W) to the same extent as when only the cosmetic composition containing dihydroxyacetone alone was used. A slight browning of the skin was observed, but unlike the yellowing of the red color, such as when using dihydroxyacetone in combination with Lawson, undesired coloring of the skin color does not occur.

[0031]

Example 2 Next, examples of other emulsions and UV-A absorption effect will be described. <Manufacturing Method> The components of Table 3A and B are dissolved at 70 ° C. with stirring. The component A is added to the component B, preliminarily emulsified, uniformly emulsified with a homomixer, and after emulsification, cooled to 50 ° C while stirring. 5 in this emulsion
Add the component C, which was heated to 0 ℃ and kept warm, while stirring. 3
Cool with stirring to 0 ° C.

[0032]

[Table 3]

<UV-A Absorption Effect> In order to examine the UV-A absorption effect of the emulsions of Example 2 and Comparative Example 2 obtained by the above production method, SPF (Sun protection factor:
The sunscreen index) value was measured.

The SPF measurement method was carried out by the following alternative method using guinea pig skin epidermis. This method is FD
Method A (a method of applying the sunscreen agent to human skin and irradiating it with ultraviolet rays, and expressing it as the ratio of the amount of irradiation energy (time) that causes inflammation equivalent to the skin when the sunscreen agent is not used) This is a method showing a very high correlation.

The skin tissue of the hairless guinea pig is peeled off,
Fat and muscle under the dermis are removed with tweezers, and dispase (Proteolytic enzyme manufactured by Godo Shusei Co., Ltd .: Bacillus polymixa) is immersed in phosphate buffered saline containing 1000 PU / ml, and the temperature is 2 to 37 ° C. It was treated for 3 hours and dried.

The artificial light source was a Model 14S type solar simulator manufactured by Solar Light Co., and the UV intensity meter was a UVR-305 / 365D (III) UV radiometer manufactured by Topcon. The wavelength of the irradiated ultraviolet rays was 290 to 400 nm (UVB + UVA region), the ultraviolet intensity was 7 mW / cm ² , and the irradiation time was 5 minutes.

On the surface side of the hairless guinea pig epidermis,
Each emulsion was applied at a concentration of 2 mg / cm ^2, and this film was 7.6 cm × having a 2 cm × 2 cm square window.
It was adhered to the window of a 3.6 cm rectangular holder and held vertically by a stand.

The irradiation portion of the solar simulator is placed on the sample surface of this epidermis, and the light receiving portion of the ultraviolet intensity meter is placed on the other surface, and the ultraviolet intensity E (mW / cm) that passes through the sample and the epidermis is set.
² ) was measured. Similarly, 30 minutes after applying the sample, a 10 cm × 10 cm white cotton cloth is pinched with tweezers, and the applied surface is rubbed lightly 20 times, and the transmitted UV intensity (E ₁ )
Was measured. On the other hand, the transmitted UV intensity (E ₀ ) was similarly measured using the above hairless guinea pig skin without application of the sample, and E / E ₀ and E ₁ / E ₀ were SPF and SPF after rubbing, respectively.
And

As a result, the emulsion of Example 2 had an SPF of 6,
The SPF after rubbing was 5.4, and the residual rate was 90%, which clearly indicates that the cloth is strong against rubbing. The emulsion of Comparative Example 2 had an SPF of 2. From this result, it is clear that the UV protective cosmetic of the present invention in which dihydrokihiacetone is used in combination with tryptophan has a higher SPF than the cosmetic of the comparative example containing dihydrokihiacetone alone.

[0040]

INDUSTRIAL APPLICABILITY The UV protective cosmetic composition of the present invention absorbs UV rays in the UV-A region by using an amino acid having excellent skin affinity and dihydroxyacetone in combination without coloring the skin to an undesired skin color. The effect can be given to the skin, and it is possible to prevent sunburn even in the sunlight and ultraviolet rays.

[Brief description of drawings]

FIG. 1 is a diagram showing absorption spectra of dihydroxyacetone, tryptophan, and a mixture thereof.

Claims (2)

[Claims] 1. An ultraviolet protective cosmetic containing 0.1 to 10% by weight of dihydroxyacetone and 0.01 to 10% by weight of tryptophan with respect to the total amount of the cosmetic. 2. A cosmetic comprising a first cosmetic containing dihydroxyacetone and a second cosmetic containing tryptophan, wherein the content of dihydroxyacetone in the first cosmetic is 0.1. UV protection cosmetics, wherein the content of tryptophan in the second cosmetic is from 0.01 to 10% by weight.