JPH0283312A - Suncreen cosmetic - Google Patents

Abstract

PURPOSE:To obtain a sunscreen cosmetic, containing a powdery cerium oxide as an active ingredient, capable of exhibiting excellent ultraviolet ray scattering and absorbing effects within a wide range, excellent in dispersibility and transparency, having stability for a long period and showing excellent sunscreen effects. CONSTITUTION:A sunscreen cosmetic, obtained by blending a powdery or fine powdery cerium oxide having <=10mu maximum particle diameter and 1-0.001mu average particle diameter as an active ingredient with other ingredients and capable of protecting the skin from noxious ultraviolet ray. The blended active ingredient is added in an amount of preferably 1-30wt.%. The above-mentioned cosmetic embraces finish (makeup) cosmetics including foundation and is used in the form of lotion, cream, paste, stick, powder, etc. Furthermore, surface treatment, such as surface coating treatment, activator treatment or metallic soap treatment, is carried out with a normally known fat and oil raw material for the purpose of improving dispersibility and usability in order to utilize characteristics in blending and the resultant active ingredient can be blended.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sunscreen cosmetic characterized by containing powdered cerium oxide.

(Prior Art) For humans, it has been reported that excessive ultraviolet rays can cause acute dermatitis of the skin, and that prolonged exposure to UV rays can cause premature skin aging and skin cancer.

Generally, this ultraviolet light is divided into three bands.

That is, the wavelength of 320 to 400 nm, which promotes melanin production in the skin and causes browning, is called the suntan wavelength.
Long wavelength ultraviolet rays (UV-A), called sunburn wavelengths, cause inflammation such as erythema and blisters on the skin.
320nm ultraviolet (UV-B), and 240-280nm low-wavelength ultraviolet (UV-B) that is absorbed in the atmosphere but rarely reaches the earth's surface and poses no problem for the human body.
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Normally, sunburn cosmetics and sunscreen cosmetics are used to protect the skin from ultraviolet rays that are harmful to the human body. It is used to prevent inflammation such as erythema and blisters, and to provide a healthy tan.

On the other hand, sunscreen cosmetics block sunburn and ultraviolet rays of suntan wavelengths, and protect the skin from ultraviolet rays over a wide range.

Conventionally, sunscreen cosmetics and sunscreen cosmetics have incorporated and utilized ultraviolet blocking agents for the above-mentioned purpose.v:
External radiation blocking agents are classified into ultraviolet absorbers, which absorb light energy, and ultraviolet scattering agents, which scatter ultraviolet rays, depending on their actions and mechanisms.

Known UV absorbers include benzophenone, benzoic acid, nitrile, and cinnamic acid absorbers. The absorption band of these ultraviolet absorbers exists in the range of 280 to 350 nm, which is not necessarily sufficient to prevent a wide range of ultraviolet rays, and a large amount of these ultraviolet absorbers must be blended for that purpose. However, ultraviolet absorbers have unfavorable aspects in terms of skin safety, and there is currently a tendency to use them sparingly. In addition, by increasing the amount of formulation, solubility in cosmetics, safety, etc.
The impact on products is also an issue.

Therefore, ultraviolet scattering agents are used to block a wide range of ultraviolet rays. Ultraviolet scattering agents include titanium oxide, zinc oxide, etc., and are usually used in sunscreen cosmetics. ) or sunscreen makeup cosmetics containing fine particulate titanium oxide (
There are proposals such as Special Publication No. 63-28400).

On the other hand, examples of using cerium as an ultraviolet blocking agent include, for example, blending it into glass and the like. However, sunscreen cosmetics containing this compound have not been known at all so far.

(Problems to be Solved by the Invention) The sun protection effects of conventionally used ultraviolet scattering agents such as titanium oxide and zinc oxide are not necessarily satisfactory. These effects are only the short-wavelength scattering effect of light due to the fine particles and the light blocking effect due to the powder layer, and there is no ultraviolet absorption effect. Therefore, titanium oxide,
Zinc oxide and the like must always be used in combination with UV absorbers to obtain a satisfactory UV blocking effect.

In view of these circumstances, the present inventors conducted intensive research on cerium oxide, which had never been used as a sunscreen. and the average particle size l to 0.001
A sunscreen cosmetic that shows excellent UV scattering and UV absorption effects over a wide range, has excellent dispersibility and transparency, and has long-term stability by incorporating micronized cerium oxide powder into cosmetics. The present invention was completed based on the discovery that the following can be obtained.

Therefore, an object of the present invention is to provide a sunscreen cosmetic characterized by blending powdered cerium oxide into a cosmetic base material.

(Means for Solving the Problems) The powdered cerium oxide of the present invention preferably has a maximum particle size of l
0μ or less, and the average particle size is 1 to 0.001μ.

Figure 1 shows the relationship between the ultraviolet transmittance and ultraviolet wavelength of the finely powdered cerium oxide and powdered titanium oxide of the present invention.

As for the measurement method, each powder was added to acrylic resin, mixed uniformly, formed into a plate shape, and measured using a spectrophotometer.

As is clear from this figure, it exhibited a significantly superior ultraviolet blocking effect.

The powder or finely powdered cerium oxide of the present invention has an excellent effect of blocking sunburn wavelengths and sunturn wavelengths compared to conventional products, and while conventional titanium oxide and zinc oxide do not have ultraviolet absorption ability, the powder of the present invention Alternatively, finely powdered cerium oxide has an excellent ability to absorb ultraviolet rays, and cosmetics containing them clearly showed a remarkable blocking effect. Therefore, sunscreen cosmetics using powdered or finely powdered cerium oxide are useful for protecting the skin from harmful ultraviolet rays.

In particular, by making cerium oxide into a fine powder, visible light transmission is improved and it is transparent, making it possible to obtain a cosmetic film that does not look unnatural when applied to cosmetics. Furthermore, even when mixed with raw materials, color development is not hindered, and color toning and covering power can be easily adjusted.

In addition, by reducing the particle size, when incorporated into cosmetics, it not only improves dispersibility but also improves usability such as improved texture, spreadability during application, adhesion, sliding feel, and long-lasting makeup effect. do.

In addition, powdered or finely powdered cerium oxide is an inorganic substance and has high skin safety.

As mentioned above, the excellent characteristics of tanning cosmetics containing the powder or unoxidized cerium of the present invention are as follows. There is no need for ultraviolet blocking or absorbing agents, but if desired, ultraviolet absorbing agents such as benzophenone derivatives, benzoic acid derivatives, salicylic acid derivatives, cinnamic acid derivatives, titanium oxide, kaolin, calcium carbonate, zinc oxide, etc. can be used. An ultraviolet scattering agent may also be appropriately blended.

The blending amount of the powder or finely powdered cenium oxide used in the present invention is preferably in the range of 1 to 30% by weight; if it is less than 1% by weight, the UV blocking effect will not be sufficient, and if it is more than 30% by weight. This tends to make it impossible to obtain a natural cosmetic film, which is an undesirable aspect.

Cosmetics in the present invention include finishing (makeup) cosmetics such as foundations, and may be in any form such as lotion, cream, paste, stick, powder, etc., and are limited to these. It's not a thing.

When blending the powder or finely powdered cerium oxide of the present invention, in order to take advantage of its properties, surface coating treatment with commonly known oil and fat raw materials, activator treatment, metal soap treatment, etc. It is also possible to compound the compound after surface treatment.

(Examples and Comparative Examples) Example 1 Sunscreen cosmetic (formulation) Ingredient A Heavy weight % stearic acid 3.5 cetanol
2.0 beeswax
3.5 Liquid paraffin oil 12.
0 Methyl phenyl silicone 4.0 Olive oil 14.0 Polyoxyethylene sorbitan monostearate butyl paraben powder cerium oxide (0.03μ) Fragrance 0, 5 0, 05 5, 0 0, 2 B component Propylene glycol triethanol Aminum sand methylparaben Non-ionized water 10.0 1.0 0,5 0,05 Remaining amount 100.00 (Production method) 1. Mix component A other than fragrance, heat and dissolve to uniformly disperse.

2. Mix 8 ingredients, heat) and dissolve.

3. Add component B to component A, emulsify while stirring, and cool.

4. Add flavoring while cooling and stir well.

5. Fill the container and use it as a product.

Comparative Example 1 Sunscreen Cosmetics Same as Example 1 except that 5g of unoxidized titanium (0.03μ) was used instead of powdered cerium oxide (0.03μ) in the formulation of Example 1. I went and got the product.

Example 2 Sunscreen Cage Foundation (Formulation) Ingredient A Talc Sericite Kaolin Powder Cerium Oxide (0° Colored Pigment Ingredients Isostearate Gum Heavy Electricity % Remaining Amount 17.0 11.0 03μ) 20.0 1! i amount 3.5 1,5 Sorbitan sesquioleate 0.8 Liquid paraffin 2.6 Octyldodecanol 3.3 Octyldodecyl myristate 1.5 Methylparaben
0. 1 Butylparaben 0
．． IC ingredient fragrance 0.2100
．． 0 Comparative Example 2 Sunscreen Cake Foundation A product was obtained in the same manner as in Example 2, except that 20g of powdered titanium oxide (0.03μ) was used instead of powdered cerium oxide (0.03μ) in Example 2. .

(Production method) 1. After mixing ingredients A with a Henschel mixer,
Add the ingredients and mix again using the Henschel mixer.

2. After adding component C to the above and performing mixing treatment and toning,
Pulverize with an atomizer.

3. Pour this powder into a metal container and press and mold it using a press.

(Results of evaluation of sun protection effect) The backs of Rootray white guinea pigs were shaved and hair removed.
Each sample (Example 1, Example 2, Comparative Example 1 and U Comparative Example 2)
) is applied to a certain area and irradiated with ultraviolet light.

The conditions for ultraviolet irradiation are Toshiba fluorescent lamp FL-2 as the light source.
O3 and FL-20BLB are each connected to three lantern rows, and 2 MED (minimum erythema dose) ultraviolet rays are irradiated from a distance of 10 cm.

As a result, Comparative Example 1 and Comparative Example 2 showed erythema and had no sun protection effect, but Example 1 and Example 2 showed
It showed no erythema and was effective in preventing sunburn.

[Brief explanation of drawings]

FIG. 1 shows the relationship between ultraviolet transmittance and ultraviolet wavelength. a-Fist/acrylic plate b...1% addition of cerium oxide (0.03μ) C...
Addition of 1% titanium oxide (0.03μ) (effect) The sunscreen cosmetic containing powdered cerium oxide of the present invention has excellent ultraviolet scattering and ultraviolet absorption effects over a wide range, and has excellent dispersibility and transparency. Excellent, long-term stability, and excellent sun protection effect. Transmittance (%) Patent applicant Daiichi Engineering Co., Ltd. Hasegawa Perfume Co., Ltd.

Claims (1)

[Scope of Claims] 1. A sunscreen cosmetic containing powdered cerium oxide as an active ingredient. 2. Maximum particle size is 10μ or less and average particle size is 1 to 0.00
A sunscreen cosmetic containing 1 μm of finely powdered cerium oxide.