JP2636355B2 - Composite particles - Google Patents

Abstract

PURPOSE:To obtain complex particles useful for foundation cosmetic, having excellent ultraviolet light screening effects, containing parent material particles comprising nylon resin, polyethylene resin, etc., carrying powder of zirconium oxide, etc., on the surface, having dispersed powder of titanium oxide, etc., in the interior. CONSTITUTION:Complex particles which contain parent material particles comprising nylon resin, polyethylene resin, polymethyl methacrylate resin, polyester resin, polystyrene resin, polyurethane resin, silicon resin or silicon oxide, carry one powder selected from zirconium oxide and aluminum oxide on the surface of the parent material particles and have dispersed one powder selected from titanium oxide and zinc oxide in the interior of the particles. The parent material particles are preferably spherical and may be columnar or cylindrical. In the case of spherical shape, the particles have 0.5-100mum. preferably 2-20mum average particle and in the case of the other shapes, the particles have 1-100mum, preferably 5-20mum average particle diameter calculated as spherical shape.

Description

Description: TECHNICAL FIELD The present invention relates to composite particles suitable for use in cosmetics such as foundations useful as sunscreen agents.

(Prior Art) When a human body is exposed to sunlight, the ultraviolet rays have undesirable effects on health or beauty, such as darkening of skin and promotion of aging. For this reason, cosmetics such as foundations used as sunscreen agents usually contain a substance for reflecting or absorbing ultraviolet rays to block them.

Conventionally, as such an ultraviolet ray blocking substance,
A composite particle described in -27532 is known. The conventional composite particles have a surface layer of a base particle made of a copolymer nylon resin of nylon 6 and nylon 12 carrying a zirconium oxide powder. The zirconium oxide powder mainly reflects ultraviolet rays to block ultraviolet rays. It is supposed to. However, this conventional composite particle has a problem that although the reflectance of ultraviolet rays by zirconium oxide is high, the ultraviolet rays that cannot be completely reflected easily pass through the base material particles, and the effect of blocking ultraviolet rays is not sufficient.

Japanese Patent Application Laid-Open No. 61-194010 describes composite particles in which powder of titanium oxide or zinc oxide is supported on the surface of base material particles made of nylon 6 resin or nylon 12 resin. This is because titanium oxide or zinc oxide on the surface mainly absorbs and blocks ultraviolet rays. However, these conventional composite particles have titanium oxide and zinc oxide, which have a high ultraviolet absorbing effect, appearing on the surface.If they are used in cosmetics, they may cause discoloration of oils and fats or, in severe cases, rough skin. And so on, and improvement is desired.

(Problems to be Solved by the Invention) An object of the present invention is to solve the above-mentioned problems of the above-mentioned conventional composite particles, to have an excellent effect of blocking ultraviolet rays, and to prevent rough skin even when used in a cosmetic. The purpose is to provide a composite particle which is less likely to cause.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a mother material made of a nylon resin, a polyethylene resin, a polymethyl methacrylate resin, a polyester resin, a polystyrene resin, a polyurethane resin, a silicone resin or silicon oxide is used. Material particles, at least one powder selected from zirconium oxide and aluminum oxide is supported on the surface of the base material particles, and inside the base material particles, titanium oxide and zinc oxide are used. Composite particles are provided, wherein at least one selected powder is dispersed.

In order to explain the present invention in more detail, the base material particles are made of nylon resin, polyethylene resin, polymethyl methacrylate resin, polyester resin, polystyrene resin, polyurethane resin, silicone resin or silicon oxide. Among them, nylon resin and silicone resin,
Silicon oxide is preferred. There are various types of nylon resins, but a nylon 6 resin, a nylon 12 resin, and a copolymer resin of nylon 6 and nylon 12 are preferable.

The shape of the base material particles described above is preferably spherical, but may be columnar, rod-like, plate-like, or the like. The average particle diameter is in the range of 0.5 to 100 μm, preferably 2 to 20 μm when the shape is spherical, and columnar, rod-like, and plate-like,
It is in the range of 1 to 100 μm, preferably 5 to 20 μm in terms of sphere. When the average particle diameter of the base material particles is within the above-described range, it becomes possible to sufficiently carry powder of zirconium oxide or aluminum oxide having an ultraviolet ray, which is mainly described below, on the surface thereof, which has a reflecting effect. In addition, it becomes possible to sufficiently disperse a titanium oxide or zinc oxide powder which mainly absorbs ultraviolet rays, which will be described later, therein. Further, when the average particle diameter of the base material particles is in the range described above, when compounding the composite particles into a cosmetic,
Less discomfort is given to the user.

The powder of zirconium oxide or aluminum oxide carried on the surface of the base material particles mainly gives the composite particles a function of reflecting ultraviolet rays. These may be used alone or as a mixture. The average particle size is in the range from 0.005 to 2 μm, preferably from 0.01 to 0.5 μm. When the average particle diameter is in the above-mentioned range, the supportability on the base material particles is improved, and not only the roughness of the composite particles is reduced, but also the sliding property is improved.

The powder of zirconium oxide or aluminum oxide is also preferably spherical, and is usually supported in a semi-submerged state on the surface of the base material particles, and usually covers the surface in a single layer. Quantitatively, base metal particles containing titanium oxide or zinc oxide
It is in the range of 10-60% by weight, preferably 20-40% by weight.
If the amount is too small, the surface of the base material particles cannot be completely covered. If the amount is too large, some particles may not be supported on the surface of the base material particles, and the slipperiness may be impaired.

The powder of titanium oxide or zinc oxide dispersed inside the base material particles mainly gives the composite particles an ultraviolet absorbing effect. Again, even when used alone,
You may mix and use. Average particle size is 0.005 to 2μ
m, preferably in the range of 0.01 to 0.5 μm. When the average particle diameter is within the above range, the dispersibility inside the base material particles is improved.

Titanium oxide and zinc oxide powders are spherical, columnar, rod-like,
The shape may be any of a plate shape and an irregular shape. The amount is 5 to 60% by weight, preferably 8 to 50% by weight based on the base material particles.
% By weight. If the amount is too small, the effect of absorbing ultraviolet rays is reduced, and if it is too large, the dispersibility inside the base material particles is reduced.

The composite particles of the present invention can be produced by various methods. That is, first, base material particles in which titanium oxide or zinc oxide is dispersed are obtained. This includes the method described below.

That is, when the base material particles are composed of, for example, a nylon resin, a cyclic lactam is heated and dissolved in paraffin or the like, and a desired amount of powder of titanium oxide or zinc oxide is added thereto. For example, phosphorus trichloride is added to carry out alkali polymerization to obtain particles. Further, the particles are separated by filtration, washed with an organic solvent such as benzene or isopropyl alcohol, and dried.

When the base material particles are composed of a silicone resin, a powder of titanium oxide or zinc oxide is added to and mixed with an aqueous solution of ammonia or an amine, and further, a hydrolyzable silane such as chlorosilane, hydrogen silane, alkoxysilane, Hydrolysis and condensation reactions are performed by adding acetoxysilane to form particles. Further, the particles are filtered off, washed with water and dried.

When the base material particles are composed of silicon oxide, first, a suspension of titanium oxide or zinc oxide is added to sodium silicate to prepare a suspension. On the other hand, a mixed solution of a surfactant and an oil-based dispersant such as benzene is prepared, and the above-described suspension is added to the mixed solution and emulsified to obtain a water-in-oil dispersion type emulsion. A salt such as ammonium chloride is added to react with sodium silicate to form particles.
Further, the particles are separated by filtration, washed with water, washed with an organic solvent such as methanol, and dried.

Next, powder of zirconium oxide or aluminum oxide is carried on the surface of the base material particles obtained by the above-described method and in which powder of titanium oxide or zinc oxide is dispersed. There are various ways to do this.

That is, for example, when the base material particles are made of a nylon resin or a silicone resin, powder of zirconium oxide or aluminum oxide is attached to the surface by using the chargeability of the nylon resin or the silicone resin, and furthermore, the automatic Apply physical force using a mortar, hybridizer, or the like. At this time, frictional heat is generated to soften the nylon resin or the silicone resin in the surface layer of the base material particles, and at the same time, zirconium oxide or aluminum oxide powder is sunk into the surface by physical force and carried.

When the base material particles are composed of silicon oxide, a suspension of zirconium oxide or aluminum oxide powder,
To the sol of zirconium oxide or aluminum oxide, add and mix base metal particles in which silicon oxide or zinc oxide is dispersed, and then heat at 70 to 100 ° C. to attach zirconium oxide or aluminum oxide to the surface of the particles. Let it. This is separated by filtration, washed with water, and then calcined at 400 to 500 ° C.

When the composite particles of the present invention are used by blending them in a cosmetic, a perfume, a bactericide, an antibacterial agent, a deodorant and the like are dispersed as necessary, inside the base material particles. Is also good.

(Example) Example 1 50 g of anhydrous laurolactam, 7 g of titanium oxide powder (average particle size: 0.4 μm), 200 ml of liquid paraffin (dispersion medium), and 1 g of sodium stearate (dispersion aid) Was mixed.

Next, the mixture was heated at 140 ° C. in a nitrogen atmosphere to dissolve laurolactam, and 0.2 ml of phosphorus trichloride was added as a polymerization accelerator, and the mixture was stirred for about 1 hour to carry out polymerization. Were dispersed to obtain nylon 12 particles. Further, the particles were separated by filtration, washed with boiling benzene, and dried under reduced pressure at 80 ° C. to have an average particle diameter of about 7 μm.
Thus, base material particles made of nylon 12 resin in which titanium oxide powder was dispersed were obtained.

Next, 70 g of the above base material particles and 30 g of zirconium oxide powder (average particle size: 0.1 μm) were put in an automatic mortar and mixed for 1 hour, and nylon 12 resin in which titanium oxide powder was dispersed was used. The composite particles obtained by supporting zirconium oxide on the surfaces of the base material particles were obtained.

The obtained composite particles were spherical and had an average particle diameter of about 7 μm, as shown in the scanning electron micrograph (magnification: 5000 times) in FIG.

Next, the spectral transmittance of the composite particles was examined using a self-recording spectrophotometer type 330 manufactured by Hitachi, Ltd. The measurement result is shown by a solid line in FIG. In FIG. 4, λ on the horizontal axis is the wavelength (nm), and T on the vertical axis is the light transmittance (%).
The spectral transmittance was measured by mixing well 0.1 g of the composite particles and 0.9 g of Vaseline to form a paste.
Vaseline was used as a reference sample with a sample thickness of 0.1 mm sandwiched between two quartz plates.

Further, the slip properties of the composite particles were examined. The slip property was measured using a powder bed tester PTH-1 manufactured by Sankyo Dengyo Co., Ltd., and a shear test was performed to draw a fracture envelope (Roscoe diagram), and then a fluidity index was obtained. Gender. The flowability index was 12.2 g / cm ² .

Example 2 1000 ml of 1% by weight aqueous ammonia and 20 g of titanium oxide powder (average particle diameter: 0.4 μm) were mixed to obtain a suspension.

Next, 200 g of methyltrimethoxysilane was added to the above suspension, and the mixture was stirred at 50 ° C. for 2 hours to hydrolyze.
A condensation reaction is performed, and thereafter, in the same manner as in Example 1, a composite in which zirconium oxide is supported on the surface of base particles made of a silicone resin in which a powder of titanium oxide having an average particle diameter of about 20 μm is dispersed. Particles were obtained.

The obtained composite particles were spherical and had an average particle diameter of about 20 μm, as shown in the scanning electron micrograph (magnification: 1000 times) in FIG.

Next, the spectral transmittance of the composite particles was measured in the same manner as in Example 1. The measurement result is shown by a dashed line in FIG. In addition, when the slip property was measured, it was 5.0 g / cm ² .

Example 3 50 g of titanium oxide powder (average particle size: 0.4 μm) and 200 g
mix with 24 ml of a 24% by weight aqueous sodium silicate solution,
A suspension was obtained.

Next, 300 ml of benzene containing 2% by weight of a spun nonionic surfactant was added to the suspension, and the mixture was emulsified to obtain a water-in-oil emulsion. An aqueous solution of ammonium sulfate was added and reacted with sodium silicate to obtain particles made of silicon oxide in which titanium oxide powder was dispersed. Further, the particles are separated by filtration, washed with water, washed with methanol, and dried at 100 ° C. for 1 hour. The base material having an average particle diameter of about 6 μm is made of silicon oxide in which titanium oxide powder is dispersed. Particles were obtained.

Next, zirconium oxide sol (monodisperse "Treceram" sol ZS-OA) manufactured by Toray Industries, Inc. was added to 100 g of the base material particles.
Was added to make 20 g of zirconium oxide, and further water was added to make 400 ml, and then stirred for 90 minutes.
2 hours at 100 ° C., further filtered, washed with water and 1 hour at 100 ° C.
Dried for hours.

Next, the dried base material particles are dried in air at 400 ° C. for 5 minutes.
Firing was carried out for a time to obtain composite particles in which zirconium oxide was supported on the surfaces of base particles made of silicon oxide in which titanium oxide powder was dispersed.

The obtained composite particles were spherical and had an average particle diameter of about 6 μm, as shown in the scanning electron micrograph (magnification: 5000 times) in FIG.

Next, the spectral transmittance of the composite particles was measured in the same manner as in Example 1. The measurement result is shown by a dotted line in FIG.
In addition, when the slip property was measured, it was 4.0 g / cm ² .

(Effect of the Invention) The composite particles of the present invention include base particles made of nylon resin, polyethylene resin, polymethyl methacrylate resin, polyester resin, polystyrene resin, polyurethane resin, silicone resin, or silicon oxide. At least one powder selected from zirconium oxide and aluminum oxide is supported on the surface, and at least one powder selected from titanium oxide and zinc oxide is dispersed inside the base material particles. Therefore, as shown in the examples, not only is the ultraviolet ray blocking effect very excellent, but also the sliding property is excellent. Therefore, the composite particles of the present invention are very suitable for being used in a basic cosmetic such as a foundation, or a cosmetic such as a milky lotion, a cream, a lipstick, a blusher, or a nail polish. Moreover, titanium oxide and zinc oxide, which have a high ultraviolet absorbing effect, are dispersed inside the base material particles and are not exposed to the surface as in the case of the above-described conventional composite particles, so that discoloration and rough skin of oils and fats are caused. There are few worries such as.

[Brief description of the drawings]

1 to 3 are scanning electron micrographs showing composite particles of the present invention according to different examples, and FIG.
4 is a graph showing the spectral transmittance of the composite particles shown in FIGS. 1 to 3.

Claims (1)

(57) [Claims] 1. A base material particle comprising a nylon resin, a polyethylene resin, a polymethyl methacrylate resin, a polyester resin, a polystyrene resin, a polyurethane resin, a silicone resin or silicon oxide, and the surface of the base material particle has zirconium oxide. And at least one powder selected from aluminum oxide and aluminum oxide, and at least one powder selected from titanium oxide and zinc oxide is dispersed inside the base material particles. Composite particles.