JPS6372616A - Cosmetic - Google Patents

Abstract

PURPOSE:To easily obtain a cosmetic having high masking power and excellent covering effect, effective even at a low content of coloring pigment and giving excellent feeling to the skin such as spreadability and adhesivity to the skin, smooth feeling, etc., by using plate red iron oxide as an active component. CONSTITUTION:Plate red iron oxide is compounded to a cosmetic. The amount of the oxide depends upon the type of the cosmetic, however, it is within the range of 0.1-60wt%. The plate red iron oxide used in the present cosmetic has an average particle diameter of 0.05-1mu along the direction of plane, a thickness of 0.01-0.2mu and an aspect ratio (plate diameter/thickness) of >=2.0. More preferably, the ratio of particle diameter at the 1st quartile to the 3rd quartile in the cumulative distribution curve of particle diameter is 0.67-1.50 and that of the 1st decile to the 9th decile is 0.5-2.0. The plate red iron oxide can be produced e.g. from an aqueous slurry containing 3 components comprising a ferric salt, tartaric acid and an alkaline compound.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to cosmetics, and more specifically, cosmetics containing plate-like red iron oxide, having high concealing properties, excellent adhesion to the skin, and excellent feel. Regarding cosmetics that are easy to manufacture.

[Conventional technology and problems]

Red iron oxide has conventionally been used as a red inorganic pigment in the field of cosmetics, and granular and needle-shaped particles are known.

However, in oil-based cosmetics such as oil-based foundations and lipsticks, acicular red iron oxide has a drawback that it has a high oil absorption capacity, which increases viscosity during the production of cosmetics and reduces the feeling of use of the product. Furthermore, in powder type cosmetics such as foundations and eye shadows, granular or acicular red iron oxide has the drawback of being difficult to spread and having poor adhesion to the skin.

On the other hand, mica-like iron oxide (so-called MIO) has been known as a plate-like iron oxide, but MIO has a large particle size because it is used as a rust-preventing pigment and decorative material.
Although a particle size of 2μ is obtained in Publication No. 69730, the concealing property is inferior to that of granular or acicular red iron oxide, and MI
Cosmetics containing O have problems in the range of use, such as roughness.

Therefore, there is a strong desire to develop cosmetics containing iron oxide, which have high concealing properties, have excellent texture and usability such as spreadability, adhesion to the skin, and lack of roughness, and are easy to manufacture. has been done.

[Means for solving problems]

As a result of intensive research to solve the above problems, the inventors of the present invention have found that when plate-shaped red iron oxide, especially plate-shaped red iron oxide with a specific particle size and shape, is blended, it has a high concealing property and a tactile feel. The present invention was completed based on the discovery that it is possible to obtain a cosmetic that has excellent usability and is easy to manufacture.

That is, the present invention relates to a cosmetic material characterized by containing plate-like red iron oxide.

In the present invention, the term "plate shape" refers to a hexagonal flake shape, a disk shape, a hexagonal plate shape, a rhombic plate shape, a square plate shape, etc.

The plate-shaped red iron oxide used in the present invention has an average particle size of 0.05 to 1 μ in the plate direction and a thickness of 0.01 to 0.2 μ.
and the plate ratio (plate diameter/thickness) is 2.0 or more, and more preferably, the particle size distribution is the same at the first quartile and the third quartile in the particle size cumulative distribution curve. Particle size ratio is 0.6
7 to 1.50, and the ratio of particle diameters at l/10 minute point and 9710 minute point is 0.5 to 2.0.

That is, the range of the average particle size of the plate-shaped red iron oxide used in the present invention is 0.05 to 1 μm in the plate direction (plate diameter).
The optimum particle size is 0.1 to 0.4μ. If the average particle size is larger than 1μ, the surface area is small, which reduces surface scattered light, lowers the hiding power, and gives a rough feel, which is undesirable.If the average particle size is less than 0.05μ, the wavelength of light decreases. Because the particle size is smaller than that of , it becomes more transparent.

In addition, the surface of the plate-shaped red iron oxide of the present invention can be treated with metal soap, silicone, dialkyl phosphate, N, etc., as long as its characteristics of high concealment, adhesion to the skin, and feel are not impaired.
- It may be hydrophobized with aluminum acylglutamate or the like and then incorporated into cosmetics.

The plate-shaped red iron oxide used in the present invention can be obtained, for example, by the manufacturing method described in Japanese Patent Application No. 153861/1989 filed by the present applicant. That is, it is an aqueous slurry in which three components, ferric salt, tartaric acid or/and its salt, and an alkali compound coexist, and p) I≧8.
．． 2, and the molar ratio r of tartaric acid or/and its salt and iron salt is (pH - 6,6) / 600 or more, and (pH
-2,6) / 600 or less is heated to 120° C. or higher to obtain the plate-shaped red iron oxide according to the present invention. However, the method for producing plate-shaped red iron oxide of the present invention is not limited to this method.

The amount of platy red iron oxide contained in the cosmetic composition of the present invention varies depending on the dosage form, but an appropriate amount within the range of 0.1 to 60% by weight is selected. In other words, as the amount of plate-like red iron oxide increases, the hiding power increases, but if the content exceeds 60% by weight, a normal makeup film (thickness of several microns) will completely hide the base. Even if the content is increased, the effect remains the same.

Further, if the amount is less than 0.1% by weight, sufficient effects cannot be obtained. [Effects of the Invention] The effects of the cosmetic containing the plate-shaped red iron oxide according to the present invention will be described in detail below.

The plate-shaped red iron oxide of the present invention has a higher concealing property than commercially available granular and acicular ones, and cosmetics containing it not only have an excellent covering effect, but also have a low content of color pigments. Since only a small amount is required, it is possible to obtain a cosmetic with improved feel, such as the poor spreadability characteristic of colored pigments.

〔Example〕

Next, the present invention will be explained in more detail by giving production examples for producing the plate-shaped red iron oxide of the present invention and Examples of the present invention, but the present invention is not limited to these Examples. .

Production example I Pe (No: +): + '911z012.3g 9
After adding 23.5 ml of 5N sodium hydroxide aqueous solution to the solution dissolved in 0+m-1 water and stirring, further add 9 ml of tartaric acid.
A solution of 0 mg dissolved in 15+*l of water was added and stirred well. pH of slurry using sodium hydroxide aqueous solution
The temperature was adjusted to 11.0, and the mixture was preheated to 80°C and charged into an autoclave. The temperature was raised to 160°C over 2 hours while stirring, maintained for 3 hours, and then cooled to room temperature. The precipitate was taken out, washed, and then dried at 60°C.

According to the X-ray diffraction results of the powder, the obtained reddish-brown powder is α-
It was confirmed that it was iron oxide. In addition, a scanning electron microscope (S
Observation by EM) revealed that this powder was a disk with a well-uniformed particle size. When 50 particles were randomly selected from the field of view of the electron micrograph and a cumulative distribution curve of particle size was drawn, the average diameter (plate diameter) was 0.2μ, which was the 14th particle of the cumulative distribution curve. The ratio of the particle sizes at the equinox and the third quartile was 1.25. The ratio of the particle sizes at the 1710 and 9710 minute points was 1.61. Also, the thickness is approximately 0.05
It was μ.

Production Example 2 2.3 g of 5N sodium hydroxide aqueous solution was added to a solution in which 12.3 g of Fe(NOs)i.9HzO was dissolved in 90 ml of water.
After adding 5ml and stirring, add 1g of tartaric acid 90o+g.
A solution dissolved in 5 ml of water was added and stirred thoroughly. Adjust the pt+ of the slurry to 3N M to 9.8 using an aqueous sodium hydroxide solution, charge it into an autoclave preheated to 80°C, raise the temperature to 160°C in 2 hours with stirring, hold it for 3 hours, and then transfer to room temperature. Cooled to . The precipitate was taken out, washed, and then dried at 60°C.

According to the X-ray diffraction results of the powder, the obtained reddish-brown powder is α-
It was confirmed that it was iron oxide. In addition, a scanning electron microscope (S
According to observation using EM), this powder is a disk with a well-uniform particle size, the disk diameter is approximately 0.15μ, and the thickness is approximately 0.
．． It was confirmed that it was 04μ.

Production Example 3 To a solution in which 10.8 g of FeCls 6HtO was dissolved in 9On+1 water, 23 g of a 5N aqueous sodium hydroxide solution was added.
After adding 5ml and stirring, a solution prepared by dissolving 90o+g of tartaric acid in 15n+1 water was further added and stirred well. The pl+ of the slurry was increased to 11 using an aqueous sodium hydroxide solution.
．． Adjust to
After holding for an hour, it was cooled to room temperature. Take out the precipitate,
After washing, it was dried at 60°C.

According to the X-ray diffraction results of the powder, the obtained reddish-brown powder is α-
It was confirmed that it was iron oxide. In addition, a scanning electron microscope (S
According to observation by EM), this powder is a hexagonal plate with a well-uniform particle size, the plate diameter is approximately 0.4μ, and the thickness is approximately 0.
．． It was confirmed that it was 0.06μ.

Reference Example 1 The hiding power and oil absorption of the plate-shaped red iron oxide of the present invention and the commercially available red iron oxide were measured by the following methods, and the results are shown in Table 1.

Hiding power> The sample was uniformly dispersed in white petrolatum at a concentration of 2%, made into a film thickness of 30μ in a quartz flat plate cell, and visible light (400 to 7
00 nm) was measured using a spectrophotometer, and calculated as: Hiding power (%) = 100 - transmittance.

Oil absorption amount According to JIS K 5101 pigment test method.

Table 1 From Table 1, the platy red iron oxide of the present invention clearly has a higher hiding power than the commercially available granular iron oxide, and the oil absorption of the plate-like red iron oxide of the present invention is clearly lower than that of the commercially available acicular iron oxide. I understand that.

In addition, the plate-shaped red iron oxide of Production Example 1, commercially available granular iron oxide, and commercially available acicular iron oxide were examined under an electron microscope (JSM-8 manufactured by JEOL Koji Co., Ltd.).
40 type). The electron micrographs are shown in Fig. 1, Fig. 2, and Fig. 3, respectively, and the magnification is 3.5.
000 times.

As shown in FIGS. 1 to 3, the plate-shaped red iron oxide of the present invention clearly differs in shape from commercially available iron oxide.

Example 1 (Powder foundation) Part A is mixed with a Henschel mixer, and part B, which has been heated and dissolved, is sprayed onto the mixture and further mixed. After crushing and passing through a sieve, it was filled and molded into a medium plate to obtain a powder foundation.

Ratio 151M1 (Powder Foundation) In Example 1, the plate-shaped red iron oxide of Production Example 1 was replaced with commercially available red iron oxide C shown in Table 1, and a powder foundation was obtained in the same manner as in Example 1 except for the following.

Table 2 shows the sensory evaluation results of the powder foundations obtained in Example 1 and Comparative Example 1 by five expert panels.

Table 2 Example 2 (Lipstick) A total of 100 parts A was heated and melted to make it homogeneous, part B was added thereto and uniformly dispersed using a roll mill, heated and melted again, defoamed, and poured into a predetermined mold.
It was cooled and molded.

Comparative Example 2 A lipstick was obtained in the same manner as in Example 2 except that the plate-like red iron oxide of Production Example 2 was replaced with commercially available red iron oxide C shown in Table 1.

Table 3 shows the sensory evaluation results of the lipsticks obtained in Example 2 and Comparative Example 2 by five expert panelists.

Table 3 Example 3 (Oil-based foundation) Part B was heated and dissolved, Part A was added thereto, uniformly dispersed using a roll mill, melted again by heating, and poured into a container to obtain an oil-based foundation.

Comparative Example 3 An oil-based foundation was obtained in the same manner as in Example 3 except that the platy red iron oxide of Production Example 3 was replaced with commercially available red iron oxide C shown in Table 1.

The oil-based foundation of Example 3 showed less increase in viscosity when the powder was dispersed in the oil phase than the oil-based foundation of Comparative Example 3, and was easier to manufacture.

Table 4 shows the sensory evaluation results of the oil-based foundations obtained in Example 3 and Comparative Example 3 by five expert panels.

Table 4 Example 4 (eyebrow ink) Eyebrow ink was obtained in the same manner as in the manufacturing method of Example 1.

The obtained eyebrow ink had excellent usability such as coloring power, gloss, and spreadability on the skin.

[Brief explanation of the drawing]

FIG. 1 is an electron micrograph of a plate-shaped red iron oxide of the present invention, FIG. 2 is an electron micrograph of a commercially available granular iron oxide, and FIG. 3 is an electron micrograph of a commercially available acicular iron oxide. Applicant's agent Kaoru Furuya Figure 1 Figure 2 Figure 5

Claims (1)

[Scope of Claims] 1. A cosmetic characterized by containing plate-like red iron oxide. 2. The average particle size of the plate-shaped red iron oxide is 0.
05 to 1μ, the thickness is 0.01 to 0.2μ, and the plate ratio (plate diameter/thickness) is 2.0 or more.
Cosmetics listed in section. 3. In the cumulative distribution curve of the particle size of plate-shaped red iron oxide, the ratio of the particle size at the first quartile and the third quartile is 0.67 to 1.
．． 50, and the ratio of the particle diameters at the 1/10 minute point and the 9/10 minute point is 0.5 to 2.0.
Cosmetics listed in section.