JP3401039B2 - Cosmetics - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cosmetic raw material using ultrafine metal oxide powder having a particle size of 0.1 μm or less. The present invention also relates to a cosmetic material raw material using ultrafine metal oxide powder having improved dispersibility.

[0002]

2. Description of the Related Art Generally, metal oxide powder having a particle diameter of 0.2 to several μm has been conventionally used as a raw material powder for cosmetics as a raw material for color pigments, white pigments and extender pigments. For example, titanium oxide powder having a particle size of 0.2 to 0.3 μm is used as a white pigment raw material in makeup cosmetics. In addition, it is blended into foundations and the like by utilizing the magnitude of its hiding power. The zinc oxide powder having a particle size of 0.3 to 0.7 μm is used as a white pigment raw material and has a weak astringent effect on the skin, so cosmetics and the like for calming the skin's burning due to sunburn, etc. Is compounded in.

Furthermore, recently, a new effect has been found by making the metal oxide powder into ultrafine particles having an average particle size of 0.1 μm or less, and it has been used in various cosmetics. For example, ultrafine titanium oxide powder having an average particle size of 0.03 μm shows almost no pigment characteristics and does not affect hue.
Since it can be added, it is used to protect against ultraviolet rays and is said to be a cosmetic product with a natural finish that does not cause whitening.

Further, the ultrafine zinc oxide powder having an average particle diameter of 0.02 μm is superior to ordinary zinc oxide in ultraviolet absorbing effect, antibacterial and antifungal effect, deodorizing effect, astringent effect and the like,
Since it has a small particle size and a low refractive index, it is almost transparent, and it can be added without affecting the hue of cosmetics, so it is used in various fields. Further, the ultrafine aluminum oxide powder and the ultrafine silicon oxide powder are
It has a thickening effect and can be used as a thickener for cosmetic creams, cosmetic emulsions and cosmetic gel products.

However, although it is an ultrafine particle metal oxide which can be expected to have the above new effects, the particle size is 0.1 μm.
If the following ultrafine particles are used, the bulk density becomes extremely large, and even if the air flow is a little, they are easily scattered and difficult to handle. Further, since the cohesive force becomes large and the dispersion becomes difficult, the dispersion state of the ultrafine particle metal oxide in the actually used state is not so fine, and there is a problem that the effect of utilizing the ultrafine particles is not sufficiently exhibited.

[0006] In general, cosmetics containing the above-mentioned ultrafine metal oxides have been produced in the same manner as the conventional production of coarse metal oxides. That is, the mixing and dispersion treatment with other raw material powder is performed by using a liquid propeller mixer,
A colloid mill, pebble mill, ultrasonic emulsifier, etc. were used. In addition, cream-like or gel-like products, kneader,
A roll mill and a crusher are used. However, since the ultrafine metal oxide has a fine particle diameter of 0.1 μm or less, it is strongly aggregated and cannot be dispersed by the usual disperser as described above. The prepared cosmetics do not fully exhibit the characteristics and functions of the ultrafine particles.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention solves the problem of using conventional ultrafine particles, that is, solves the difficulty of handling ultrafine metal oxide raw material powders, and facilitates ultrafine particles. It is an object of the present invention to provide a cosmetic raw material capable of uniformly dispersing a metal oxide powder.

[0008]

In order to solve the above technical problems, the present invention blends a dispersion medium of water with ultrafine zinc oxide particles having an average particle size of 0.1 μm or less and a dispersant. The cosmetic raw material, wherein the dispersant is sodium polyacrylate, the content of the zinc oxide ultrafine particles in the cosmetic raw material is 30 to 50% by weight, and the polyacrylic acid is based on the zinc oxide ultrafine particles. The amount of soda added is 0.5 to 20% by weight, and the zinc oxide ultrafine particles are flat.
A cosmetic raw material having a uniform particle size of 0.1 μm or less is provided. The present invention is also a cosmetic raw material in which an oil-based dispersion medium is mixed with zinc oxide ultrafine particles having an average particle size of 0.1 µm or less and a dispersant, wherein the dispersant is polysiloxane, and the cosmetic raw material is The content of the zinc oxide ultrafine particles is 30 to 50% by weight, and the amount of the polysiloxane added to the zinc oxide ultrafine particles is 0.5 to 20.
% By weight, and the zinc oxide ultrafine particles have an average particle size of 0.
A cosmetic raw material dispersed to 1 μm or less is provided. And, the polysiloxane is a methyl silicone resin.
That what is preferred.

[0009]

In the cosmetic composition of the present invention, in order to improve the handling difficulty and dispersion difficulty of the ultrafine metal oxide powder,
Ultrafine metal oxide powder having a particle size of 0.1 μm or less is homogeneously dispersed in a medium or medium such as water, alcohol or oil that can be used as a cosmetic medium, and the ultrafine metal oxide is used. This is solved by using a slurry or cream or gel-like cosmetic raw material having a content of 10% by weight or more.

The details will be described below. The cosmetic raw material of the present invention comprises ultrafine metal oxide powder, a dispersion medium and a dispersant. That is, the ultrafine metal oxide powder used in the present invention has a dispersed particle diameter of 0.1 μm or less, and is used for the purpose other than white pigments, coloring pigments, and extender pigments for the purpose of using the metal oxide powder having the conventional particle diameter. It is included in the ingredients. Specifically, it is a compounding component capable of improving various functions such as transparency, ultraviolet absorption, infrared reflection and absorption, antibacterial, antifungal, deodorant and astringent properties.

As such, as ultrafine metal oxide powder, for example, ultrafine zinc oxide powder, ultrafine titanium oxide powder, ultrafine iron oxide powder, ultrafine cerium oxide powder, ultrafine zirconium oxide powder, etc. Can be used. Ultrafine zinc oxide powder has a particle size of 50-
Those having a volume of 500 Å can be obtained by the method described in JP-A-2-311314. Compared with conventional zinc oxide powders, such ultrafine zinc oxide powders have large drug effects such as UV absorption, antibacterial, antifungal, deodorant, and astringent effects, and are superior in transparency, and therefore cosmetics. It can be added without changing the hue of the material.

Further, as the ultrafine titanium oxide powder,
MT-500B (Tayca), TTO-55 (A) (made by Ishihara Sangyo), P-25 (Degussa), etc. are used, with a particle size of 200 to 500Å, excellent transparency, and a hue when added to cosmetics. It can be added as a UV-screening agent for sunscreen cosmetics because it does not change and has a UV-absorbing effect. In addition, as for the ultrafine iron oxide powder, a powder made of goethite is called a yellow iron oxide powder, and a powder made of hematite is called a red iron oxide powder.
It has 0 to 1000Å and has no hiding power, and has ultraviolet and infrared absorbing effects. Such fine iron oxide powder is
It can be prepared by the method described in USP 2,357,096, Japanese Examined Patent Publication No. 43-11166 and USP 2,558,302 to 2,558,304.

The ultrafine cerium oxide powder has a particle size of 50 to 100Å and has an ultraviolet absorbing function and an infrared absorbing function, and can be prepared by the method described in JP-A-4-205761. The ultrafine zirconium oxide powder can be prepared by the method described in JP-A-61-291417.

These ultrafine metal oxide powders can be used alone or as a mixture.
For example, when it is used for the purpose of imparting an ultraviolet absorbing effect or an infrared absorbing effect, the absorption wavelengths of the metal oxides are different, so that it is more effective if they are used as a mixture.

Further, as the dispersion medium used in the present invention,
Water or a mixture of water and alcohol or various oil-based dispersion media may be used. As the water, purified water specified in the cosmetic raw material standard is used. Further, the alcohol is preferably a water-soluble lower alcohol, and examples thereof include ethanol and isopropanol. In addition, a water / alcohol mixed solution can be similarly used.

As the oily dispersion medium, animal and vegetable oils having a freezing point of 80 ° C. or lower and fatty acids or higher alcohols obtained by chemically treating the same are preferable, and mineral oils or chemically synthesized oils can also be used. Examples of animal and vegetable oils include coconut oil, olive oil, castor oil, semi-hardened cottonseed oil, hydrogenated castor oil, lanolin, beeswax and squalane. Fatty acids obtained by chemically treating animal and vegetable oils include stearic acid, oleic acid, mistyric acid, and lauric acid, and higher alcohols include stearyl alcohol, oleyl alcohol, and mistyryl alcohol obtained by reduction of the above fatty acids. , Lauryl alcohol and the like. Examples of the mineral oil include liquid paraffin and vaseline, and examples of the chemically synthesized oil include silicone oil.

In the dispersion treatment, addition of a dispersant is effective in improving dispersibility and dispersion stability. The dispersant used in the present invention is not particularly limited as long as it complies with the raw material standards for cosmetics such as the cosmetic raw material standard, but as a suitable dispersant for ultrafine metal oxides, HLB4 to There are 18 surfactants and water-soluble polymers and solvent-soluble polymers.

Examples of the above-mentioned surfactants include anionic surfactants such as higher fatty soaps, higher alcohol sulfate ester salts, sulfonates and higher alcohol phosphates, and quaternary ammonium salts such as other cationic surfactants and carvone. Examples thereof include acid type amphoteric surfactants, polyoxyethylene type, polyhydric alcohol ester type, nonionic surfactants such as ethylene oxide propylene oxide block copolymers.

As the above water-soluble polymer, guar gum, locust bingham, quince seed, carrageenan, galactan, gum arabic, tragacanth gum, pectin, mannan, starch or other plant-based natural polymer, xanthene gum, dextran, succino. Glucan, microbial natural polymers such as Gardlan, gelatin, casein,
Animal-based natural polymers such as albumin and collagen, cellulosic semi-synthetic polymers such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose and methyl hydroxypropyl cellulose, starches such as soluble starch, carboxymethyl starch and methyl starch. Type semi-synthetic polymer, alginic acid propylene glycol ester, alginic acid type semi-synthetic polymer such as alginate, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl methyl ether, carboxy vinyl polymer, vinyl synthetic polymer such as sodium polyacrylate, polyethylene oxide , Synthetic oxides such as ethylene oxide and propylene oxide block copolymers. Also,
Examples of the solvent-soluble polymer include polysiloxane.

These dispersants are adsorbed on the surface of ultrafine particles to promote wetting with the dispersion medium, impart lipophilicity and hydrophilicity, and improve dispersibility and dispersion stability due to the effect of preventing aggregation by the electric double layer or protective colloid. It is effective in improving sex.

In the cosmetic of the present invention, the ultrafine metal oxide powder as described above is dispersed in a dispersion medium containing water, alcohol or an oil containing an appropriate amount of a dispersant so as to have a dispersed particle diameter of 0.1 μm or less. That is the key. Dispersion particle size is 0.1
Even if the primary particle diameter of the raw material powder is 0.1 μm or less, the dispersed state is poor, and if the raw material powder is agglomerated, the function of the ultrafine particles cannot be brought out and the conventional coarse particles are used. This is because only the same effect as that of the metal oxide can be expected.

A propeller mixer, a disper, a homomixer, a homogenizer, a colloid mill, a pebble mill, an ultrasonic emulsifier, a kneader, a roll mill, a crusher, etc., which have been conventionally used for producing cosmetics, have a weak dispersive power, 1
It is not possible to disperse even ultrafine particles of μm or less. Therefore, the present inventor has studied the most suitable method for dispersing ultrafine particle-shaped metal oxides as a dispersion method, and as a result, by using a sand mill for dispersion, the particles can be dispersed to 0.1 μm or less. It has been found that the function can be fully exerted.

The reason why the sand mill is suitable for dispersing ultrafine particles is that the shearing force due to the flow and collision of the dispersing medium such as glass beads and sand is the dispersing force, and the shearing area is three-dimensionally distributed over the entire apparatus. They are distributed, the probability of particles being trapped between the media can be dramatically increased by making the medium small, and the shearing force is the most efficient for dispersing the agglomerated particles. For these reasons, the dispersion treatment with the sand mill can disperse the ultrafine particles most efficiently.

The proportion of raw materials when dispersed by a sand mill is
Considering dispersion efficiency, ultrafine particle concentration of 10 to 50% by weight,
A slurry viscosity of 1 to 500 cp is suitable. Such a concentration can be obtained from the flow point. That is, the dispersion medium is gradually added to the ultrafine particles and kneaded, and the point at which the fluidity is exhibited first is the optimum composition. However, because the particles become finer as the dispersion process progresses,
Since fluidity may be lost, in that case, it is necessary to add a dispersion medium as appropriate.

The addition amount of the dispersant varies depending on the particle size, surface area, number of functional groups, polarity, etc. of the ultrafine particles to be dispersed, and it is necessary to estimate the addition amount in advance by a preliminary test before compounding. , In the range of approximately 0.5 to 20% by weight.
If the dispersant is less than that, dispersibility and dispersion stability are poor,
On the other hand, if it exceeds this range, not only the dispersant is wasted but also the dispersibility may be impaired. Furthermore, the solid content of the obtained slurry will be reduced.

When the dispersion medium is water or a water / alcohol mixed solution, the ultrafine particle oxide, the dispersant and the dispersion medium are well premixed and subjected to a dispersion treatment in a sand mill for 1 to 5 hours. Also,
In the case of a water / alcohol mixed liquid medium, it can be prepared by adding alcohol to a water dispersion slurry. In the case of water and a water / alcohol mixed liquid, since the viscosity is low and the polarity of the liquid is high, a slurry having relatively good dispersibility can be obtained by the above method.

On the other hand, when dispersed in an oily medium, it can be prepared in the same manner as above in a low-viscosity oily medium, but in the case of a high-viscosity oily medium, the fluidity in the sand mill is reduced and agglomerate particles are dispersed. The dispersibility is deteriorated due to a decrease in the penetration of the oil medium. In this case, it is preferable to heat the slurry to reduce its viscosity, or to disperse it in a low-viscosity liquid, and then perform flushing treatment or solvent replacement to prepare it.

In the case of utilizing the flushing treatment, by adding a surfactant having HLB of 7 or more to the water dispersion slurry and imparting lipophilicity to the surface of the dispersion particles, the ultrafine particles are aggregated and separated into two layers from water. By separating water, mixing it with an oily medium, forcibly kneading with a kneader or the like, and expelling water, a paste-like oily dispersion can be prepared.

Further, in the method by solvent substitution, after dispersing in a low viscosity organic solvent such as isoamyl acetate, ethyl acetate, butyl acetate, ethylene glycol monobutyl ether,
It can be prepared by mixing an oil medium and distilling and separating the organic solvent. The paste-like, gel-like, or slurry-like cosmetic raw material prepared by the method described above can be used alone, but it is usually used as an additive to other main cosmetics.

Therefore, the concentration of the zinc oxide ultrafine particles of the cosmetic raw material of the present invention is preferably as high as possible within the range that does not impair the dispersibility, and at least 10% by weight is necessary. The content of fine particles is 30 to 5
It is 0% by weight. If the concentration of ultrafine zinc oxide particles is less than 10% by weight , the amount added to cosmetics becomes too large and the main component becomes
May affect the composition of cosmetics and change their properties.
There is. And zinc oxide ultrafine particles in cosmetic raw materials
If the child content is less than 30% by weight, sufficient effect in cosmetics is obtained.
If the fruit cannot be produced, and if it exceeds 50% by weight, dispersibility is impaired.
There is fear.

Next, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. However, Examples other than Examples 2 and 4 are reference examples.
It

[0032]

[Example 1] The following composition components were mixed, and a sand mill was used.
The dispersion treatment was performed for 2.5 hours to obtain a slurry having a viscosity of 12 cp. Ultrafine zinc oxide powder (average particle size 0.02 μm) ・ ・ ・ 40 parts by weight Sodium monolauryl sulfosuccinate ・ ・ ・ ・ ・ ・ 2 parts by weight Purified water ・ ・ ・ ・ ・48 parts by weight The particle size distribution of the obtained slurry was measured by a centrifugal sedimentation type particle size distribution measuring instrument (manufactured by Shimadzu Corporation). Furthermore, it preserve | saved for 3 months and observed the change of a dispersion state. The results are shown in Table 1 together with the results of other examples.

[0033]

Example 2 Further, the following composition components were mixed and dispersed in a sand mill for 2.5 hours to obtain a slurry having a viscosity of 17 cp. Ultrafine zinc oxide powder (average particle size 0.02 μm): 40 parts by weight sodium polyacrylate: 2 parts by weight Purified water :: .. 48 parts by weight The particle size distribution of the obtained slurry was measured with a centrifugal sedimentation type particle size distribution measuring device (manufactured by Shimadzu Corporation). Furthermore, it preserve | saved for 3 months and observed the change of a dispersion state. The results are shown in Table 1 together with the results of other examples.

[0034]

Example 3 Furthermore, the following composition components were mixed and dispersed in a sand mill for 2.5 hours to obtain a slurry having a viscosity of 38 cp. Ultrafine zinc oxide powder (average particle size 0.02 μm): 40 parts by weight sorbitan trioleate: 2 parts by weight Liquid paraffin :: ............ 48 parts by weight The particle size distribution of the obtained slurry was measured by a centrifugal sedimentation type particle size distribution measuring device (manufactured by Shimadzu Corporation). Furthermore, it preserve | saved for 3 months and observed the change of a dispersion state. The results are shown in Table 1 together with the results of other examples.

[0035]

Example 4 Furthermore, the following composition components were mixed and dispersed in a sand mill for 2.5 hours to obtain a slurry having a viscosity of 25 cp. Ultrafine zinc oxide powder (average particle size 0.02 μm) ··· 40 parts by weight Methyl silicone resin ··· 2 parts by weight Coconut oil ··· .............. Similarly to 48 parts by weight, the particle size distribution of the obtained slurry was measured by a centrifugal sedimentation type particle size distribution measuring instrument (manufactured by Shimadzu Corporation). Furthermore, it preserve | saved for 3 months and observed the change of a dispersion state. The results are shown in Table 1 together with the results of other examples.

[0036]

Examples 5 to 8 Instead of the ultrafine zinc oxide of Example 1, ultrafine titanium oxide (average particle size 0.04 μm), ultrafine iron oxide (average 0.05 μm), ultrafine cerium oxide (average particle size) 0.01 μm) and ultrafine zirconium oxide (average particle size 0.02 μm). Similarly, the particle size distribution of the obtained slurry was measured by a centrifugal sedimentation type particle size distribution analyzer (manufactured by Shimadzu Corporation) to measure the weight% of the dispersed particle size of 0.1 μm or less, and the dispersion stability was measured. The results are shown in Table 1 together with the results of other examples.

[0037]

Example 9 20 parts by weight of ethanol was mixed with the slurry of Example 1 and dispersed similarly. The particle size distribution and dispersion stability of the obtained slurry were measured and observed, and the results are also shown in Table 1. That is, it was found that they did not change.

[0038]

Example 10 To the slurry of Example 1 was added 2 parts by weight of sodium polyoxyethylene oleyl ether phosphate,
Similarly, as a result of mixing and dispersing for 2.5 hours with a sand mill, the slurry was separated into two layers of ultrafine zinc oxide powder in the upper part and water in the lower part. Next, the lower water layer was separated, 15 parts by weight of liquid paraffin was added thereto, and the mixture was kneaded with a kneader while heating to gradually remove water, thereby obtaining a white paste. Furthermore, add 5 parts of liquid paraffin.
0 part by weight was added, and the particle size distribution and dispersion stability were measured as a slurry-like dispersion liquid. The results are shown in Table 1 together with the results of other examples.

[0039]

[Table 1] However, the column of evaluation 1 shows the weight% of particles having a particle diameter of 0.1 μm or less, and the column of evaluation 2 shows the appearance of the slurry after standing for 3 months.

[0040]

Industrial Applicability As described above, the cosmetics of the present invention have the following remarkable technical effects. First
In addition, it is possible to provide a cosmetic material which eliminates the difficulty of handling the raw material ultrafine particle metal oxide powder and can easily and uniformly disperse the ultrafine particle metal oxide powder. Secondly, it is possible to provide an ultrafine particle metal oxide powder raw material for cosmetics which can bring out the function of ultrafine particles and a method for producing the same, that is, the shearing force is three-dimensionally distributed over the entire apparatus. By the dispersion treatment, it was possible to efficiently provide the ultrafine particle metal oxide powder raw material for cosmetics in which the dispersed particle size of the ultrafine particles was small.

Claims (3)

(57) [Claims] 1. A raw material for cosmetics, comprising a dispersion medium of water and zinc oxide ultrafine particles having an average particle size of 0.1 μm or less and a dispersant, wherein the dispersant is sodium polyacrylate.
The content of the zinc oxide ultrafine particles in the cosmetic raw material is 30 to 50% by weight, and the amount of the sodium polyacrylate added to the zinc oxide ultrafine particles is 0.5 to 20% by weight. Ultrafine particles have an average particle size of 0.1
Cosmetic raw material dispersed to less than μm . 2. A cosmetic raw material in which an oil-based dispersion medium is mixed with ultrafine zinc oxide particles having an average particle diameter of 0.1 μm or less and a dispersant, wherein the dispersant is polysiloxane, and the dispersant is a polysiloxane. The content of zinc oxide ultrafine particles is 30 to 5
0% by weight, the addition amount of the polysiloxane to the zinc oxide ultrafine particles is 0.5 to 20% by weight,
The zinc oxide ultrafine particles have an average particle size of 0.1 μm or less.
Scattered cosmetic ingredients. 3. The polysiloxane is methylsilicone.
The cosmetic raw material according to claim 2, which is a resin.