JPH08113521A - 2,4,6-trihydroxychalcone and cosmetic containing the same - Google Patents

Abstract

PURPOSE: To obtain an ultraviolet absorber high in safety which contains, as an active ingredient, 2,4,6-trihydroxychalcone distributing in a tree, Benzoin umblellatum Rehd., in high concentration, and has strong absorption in the ultraviolet A and B regions. CONSTITUTION: Bark of a tree, Benzoin umblellatum Rehd., is extracted with a polar solvent of one to 20 times volume of the bark at room temperature or near its boiling point, the extract is purified by a liquid-liquid extraction or column chromatography to collect 2,4,6-trihydroxychalcone of the formula. The 2,4,6-trihydroxychalcone is used as an active ingredient to provide an ultraviolet absorber. This absorber is added in an amount of 0.01-10wt.% to give a cosmetic. The compound of the formula has an absorption maximum at 343nm wavelength in the ultraviolet A region, its absorbance is high as much as 980 per 1% conc., thus can be used as an ultraviolet absorber which can absorb not only the B region but also the A region. This absorber is used by application to the skin as a base cosmetic in the form of cream, emulsion or lotion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet absorber composed of 2,4,6-trihydroxychalcone and a cosmetic containing the same.

[0002]

2. Description of the Related Art In recent years, due to the risk of inflammation and induction of skin cancer, consumers have been conscious of protecting the skin from UV rays, especially UV rays B. Furthermore, ultraviolet rays A
It was pointed out by many academic societies that this is not preferable in terms of safety, and the need for protection against this was emphasized.

On the other hand, as protection against ultraviolet rays, in the field of cosmetics, cosmetics in which ultraviolet rays are scattered by a masking agent such as titanium oxide, benzophenone derivatives, cinnamic acid derivatives, para-aminobenzoic acid derivatives, etc. This is done by using a cosmetic or the like that absorbs the ultraviolet rays before they reach the skin by blending the ultraviolet absorber.

However, in the case of protection due to scattering by titanium oxide, if a titanium oxide in an amount effective for protection is added, the appearance color of the titanium oxide is affected and the color becomes abnormally white. Even if it was colored, the finish would be thick and could give an unnatural feeling to others. Further, conventional ultraviolet absorbers have many safety problems such as suspected causative substances of delayed-type allergy. Further, they do not absorb ultraviolet A and cannot protect against ultraviolet A, which is not sufficient.

On the other hand, 2,4,6-trihydroxychalcone is a known substance, and it is known that it exists in the bark of Chromodis. It is also known that this substance is effective for protection against ultraviolet rays. It was never known to be used for the protection of.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is therefore an object of the present invention to provide an ultraviolet absorber capable of protecting both ultraviolet rays A and ultraviolet rays B.

[0007]

In view of such circumstances, the present inventors have searched for substances having strong absorption in the ultraviolet A and B regions using various organic compounds with the ultraviolet absorption spectrum as an index. The property was found in 2,4,6-trihydroxychalcone and the invention was completed. The present invention will be described in more detail below.

(1) Ultraviolet absorber of the present invention The ultraviolet absorber of the present invention comprises 2,4,6-trihydroxychalcone. 2,4,6-trihydroxychalcone has a structure represented by the structural formula (I), and it is known that it exists in a high concentration in Chromodis which is a plant of the Lauraceae family. This substance has absorption in the ultraviolet regions A and B, and it should be noted that the substance has an absorption maximum (343 nm) in the ultraviolet region A, which has very few substances having absorption in this region. Since the absorbance is as high as 980 in terms of the absorbance coefficient per 1%, it can be used as an ultraviolet absorber capable of absorbing not only B but also B. Further, it has a residual rate of about 90% even after irradiation with 10,000 counts of ultraviolet rays, and is excellent in stability. These 2, 4, 6
The method for obtaining trihydroxychalcone from Chromody bark may be carried out by adding 1 to 20 times the amount of a polar solvent to Chromody bark and heating at room temperature or a temperature near the boiling point for extraction. At this time, the bark may be used as it is, or may be used after being subjected to pretreatment such as drying, chopping and crushing. A suitable extraction time is several days at room temperature, and a few hours if heated.
Examples of polar solvents used include alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, ethers such as diethyl ether and tetrahydrofuran, halogenated hydrocarbons such as chloroform and methylene chloride, ethyl acetate and methyl formate, etc. Preferable examples thereof include esters, nitriles such as acetonitrile, water and the like. These may be used alone or as a mixture of several kinds. The thus-obtained extract is, after removing the solvent, purified by a usual method such as liquid-liquid extraction or column chromatography to obtain the ultraviolet absorbent of the present invention,
4,6-trihydroxychalcone can be obtained.

[0009]

Embedded image

(2) Cosmetic of the present invention The cosmetic of the present invention is characterized by containing the above-mentioned ultraviolet absorber. In the cosmetic of the present invention, the preferable blending amount of the ultraviolet absorber is 0.01 to 10% by weight.
If it is less than 0.01% by weight, the ultraviolet absorption capacity is too small and the protection from ultraviolet rays may be insufficient.
This is because the effect may reach the ceiling even if it exceeds 0% by weight. A more preferable blending amount is 0.1 to 5% by weight, which has a clear effect on the concentration.

The cosmetic of the present invention may contain various optional components usually used in cosmetics in addition to the above-mentioned ultraviolet absorber. As an optional component, hydrocarbons such as petrolatum and squalane, esters such as jojoba oil and synthetic geiro, triglycerides such as olive oil and hydrogenated coconut oil, alcohols such as cetyl alcohol and oleyl alcohol, stearic acid and oleic acid. Fatty acids such as, nonionic surfactants such as stearic acid monoglyceride and polyoxyethylene hydrogenated castor oil, anionic surfactants such as sodium lauryl sulfate and sulfosuccinate, cationic surfactants such as alkylamine hydrochloride,
Polyhydric alcohols such as glycerin and 1,3-butanediol, amphoteric surfactants such as alkylbetaine, preservatives such as parabens, antioxidants such as BHT, and ultraviolet absorbers such as paraaminobenzoic acid ester derivatives, Examples thereof include thickeners such as guar gum, pH adjusting agents such as alkali and phosphate, and various medicinal ingredients such as vitamins. Furthermore, a conventional ultraviolet absorber such as a benzophenone derivative, an aminobenzoic acid derivative, a cinnamic acid derivative, or a scattering agent such as titanium oxide or zinc oxide may be added.

The dosage form of the cosmetic of the present invention is not particularly limited, but basic cosmetics such as creams, emulsions and lotions applied to the skin are preferable. Further, it may be blended in makeup cosmetics such as eye color, cheek color, foundation, and under makeup.

[0013]

The present invention will be described in more detail with reference to the following examples, but it goes without saying that the present invention is not limited to these examples.

Example 1 Production Example 8 kg of bark of Chromody was added to 8 l of methanol, and the mixture was heated under reflux for 3 hours to remove insoluble matter by filtration, and then concentrated under reduced pressure. Chloroform and water were added to each in an amount of 1 l to perform liquid-liquid extraction, The chloroform layer is taken out, the solvent is removed, and the product is purified by silica gel column chromatography (elution solvent;
Chloroform: methanol = 100: 0 → 50: 50)
780 mg of 2,4,6-trihydroxychalcone (UV absorber 1) was obtained.

Example 2 Transdermal Toxicity The safety of the ultraviolet absorbent 1 of Example 1 was examined using 6 Hartley male guinea pigs (300-350 g).
That is, the back of the guinea pig was shaved to make three 2 × 2 cm parts. One was a non-treated control site and no operation was performed thereafter, and the other was a vehicle control, and 0.05 g of vaseline was applied. The remaining one was used as a sample administration site, and the ultraviolet absorber 1 kneaded in vaseline at a ratio of 10% by weight was applied. 24 hours later and 4
The same sample was administered 8 hours later, and the skin reaction was evaluated 72 hours later using the following Draize standard. As a result, no skin reaction was observed in any of the parts, and the judgment was (-). From this, it is understood that the ultraviolet absorber of the present invention is excellent in safety.

[Criteria for Draize] −: No reaction ±: False positive reaction +: Positive reaction ++: Reaction with edema

Example 3 Formulation Example A lotion was prepared based on the following formulation. That is, the prescription ingredients were heated and stirred at 80 ° C. to solubilize them, and then cooled to obtain a lotion. Hereinafter, all numerical values represent parts by weight. Ethanol 15 1,3-butanediol 5 Glycerin 5 Methylparaben 0.2 Perfume 0.1 UV absorber 1 0.05 Water 79.65

Example 4 Formulation Example A lotion was prepared based on the following formulation. That is, the prescription ingredients were heated and stirred at 80 ° C. to solubilize them and then cooled to obtain a lotion. Ethanol 15 1,3-Butanediol 5 Glycerin 5 Methylparaben 0.2 Perfume 0.1 UV absorber 1 0.1 Octyl paraaminobenzoate 0.1 Water 79.5

Example 5 Formulation Example A cream was prepared according to the following formulation. That is,
Weigh A and B separately, heat and stir at 80 ° C, and add A to B
Was gradually added with stirring to emulsify. This was cooled with stirring to obtain a cream. (A) Cetanol 1 Synthetic Geiro 2.5 Beeswax 2.5 Stearic acid 1 Vaseline 3 Squalane 14 Olive oil 6 Tocopherol 0.1 Butylparaben 0.1 Glyceryl monostearate 2.5 Polyoxyethylene (25) Stearate 2.5 UV absorber 1 1 (B) caustic potash 0.02 water 55.43 1,3-butanediol 8 methylparaben 0.25

Example 6 Formulation Example A cream was prepared according to the following formulation. That is,
Weigh A and B separately, heat and stir at 80 ° C, and add A to B
Was gradually added with stirring to emulsify. This was cooled with stirring to obtain a cream. (A) Cetanol 1 Synthetic Geiro 2.5 Beeswax 2.5 Stearic acid 1 Vaseline 3 Squalane 14 Olive oil 6 Tocopherol 0.1 Butylparaben 0.1 Glyceryl monostearate 2.5 Polyoxyethylene (25) Stearate 2.5 UV absorber 1 0.1 (B) caustic potash 0.02 water 56.33 1,3-butanediol 8 methylparaben 0.25

Example 7 Formulation Example A foundation was prepared according to the following formulation. That is, after kneading A, B was added and further kneaded, and after heating to 80 ° C., C was dispersed, D which was heated and dissolved at 80 ° C. was gradually added to emulsify, and the mixture was stirred and cooled to obtain a foundation. (A) 1,3-butanediol 5 malbitol 10 methylparaben 0.3 diglycerin triisostearate 4 (B) liquid paraffin 5 butylparaben 0.1 ultraviolet absorber 1 0.6 (C) titanium oxide 9 yellow iron oxide 1.7 Red iron oxide 1.2 Talc 8.1 (D) Water 55

Example 8 Photoprotective action BL of cream of Example 6 using the upper arm of 5 subjects
The photoprotective action against light using the B lamp and the SE lamp as a light source was confirmed. That is, the BLB lamp and S of the five subjects
The minimum erythema concentration (MED) for a light source equipped with four E lamps was obtained in advance, and 0.01 g of the cream of Example 6 was applied to a 1 cm × 1 cm site provided on the upper arm, and MED was applied. Of double dose of light. Twenty-four hours after irradiation, the skin reaction was evaluated using the Japanese patch test criteria shown below. As a result, none of the panelists reacted (-). Furthermore, the skin turning was observed 1 week, 2 weeks, 3 weeks and 4 weeks after irradiation, but no difference was observed between the irradiated and non-irradiated sites. From these observations, it can be seen that the cosmetic containing the ultraviolet absorbent of the present invention is excellent in protection from light and especially ultraviolet rays A and B.

[Japanese Patch Test Criteria] −: No reaction ±: False positive reaction +: Positive reaction ++: Reaction with edema

Example 9 Human Patch Test Further, in order to confirm the high level of safety, a closed patch test for 24 hours was conducted using 11 males with the ultraviolet absorbent of the present invention. That is, a sample prepared by kneading the ultraviolet absorber of Example 1 of the present invention in vaseline at a concentration of 5% by weight on the upper arm was applied to a lint cloth of a patch plaster for 0.025 g, and closed patch was applied for 24 hours. The skin reaction was observed 1 and 24 hours after removal of the patch plaster using the above Japanese patch test standard. As a result, all panelists showed no reaction (-) at all observations, and it was confirmed that the ultraviolet absorber of the present invention is extremely safe for humans.

[0025]

EFFECTS OF THE INVENTION The ultraviolet absorber comprising 2,4,6-trihydroxychalcone of the present invention is highly safe and has a strong absorption in the ultraviolet A and B regions, and therefore is very useful as a raw material for cosmetics.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akiyoshi Matsubara 27 Takashimadai, Kanagawa-ku, Kanagawa-ku, Kanagawa Prefecture 1 Yokohama Research Laboratory, Pola Chemical Industry Co., Ltd. (72) Inventor Takeru 27 Takashimadai, Kanagawa-ku, Yokohama-shi, Kanagawa 1 Pola Chemical Industry Co., Ltd. Yokohama Research Laboratory (72) Inventor Yoshio Kitada 560 Kashio-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Pola Chemical Industry Co., Ltd. Totsuka Research Laboratory (72) Inventor Taku Nakajima Kashio-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture 560 Pola Kasei Kogyo Co., Ltd. in the Totsuka Research Institute (72) Inventor Houji Hogo 1 Takashimadai 27 Takashimadai, Kanagawa-ku, Yokohama, Kanagawa Prefecture Pola Kasei Kogyo Co., Ltd. in Yokohama Research Laboratory (72) Satoshi Ohata, Takashimadai, Kanagawa-ku, Kanagawa Address 27, Yokohama Research Laboratory, Pola Chemical Industry Co., Ltd. (72) Inventor Yoshiyuki Miyata River Prefecture, Kanagawa-ku, Yokohama-shi Takashimadai 27 address 1 Pola Chemical Industry Co., Ltd. Yokohama within the Institute

Claims (3)

[Claims] 1. An ultraviolet absorber comprising 2,4,6-trihydroxychalcone represented by structural formula (I). Embedded image 2. A cosmetic containing the ultraviolet absorbent according to claim 1. 3. The cosmetic according to claim 2, wherein the content of the ultraviolet absorber according to claim 1 is 0.01 to 10% by weight.