JPS6054914A - Production of microspherical silica gel - Google Patents

Abstract

PURPOSE:To produce microspherical silica gel suitable to makeup cosmetic pigment, by granulating an aqueous solution consisting essentially of sodium silicate by spray drying, neutralizing the soda with an acid, and removing the neutralized soda therefrom. CONSTITUTION:An aqueous solution consisting essentially of sodium silicate expressed by formula, and having <=100cp viscosity is granulated by the drying, e.g. high-speed centrifugal spraying method with a rotating disk at >=7,000m/min peripheral speed. The granulated sodium silicate is then treated and neutralized with sulfuric adic in 5-10% concentration, and the sodium in the form of a water-soluble salt is simultaneously forced to the outside of granules. The granules are then dehydrated, washed with water and dried to produce microspherical silica gel having 1-60mu grain diameter. 5-30% granules are incorporated with a makeup cosmetic, e.g. foundation or eye shadow, to give a light, smooth and easily extendible cosmetic.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the production of fine spherical silica gel,
More specifically, the present invention relates to a method for producing a novel makeup pigment.

Conventional spherical silica gel is made from water glass (sodium silicate aqueous solution)
A spherical silica gel was produced by adding sulfuric acid to the solution to form a silica sol, then dispersing it in oil, making it cloudy and gelling it.

However, this method has drawbacks such as it is difficult to control the reaction time and the spherical shape becomes too large, making it difficult to obtain particles of the desired size.

There is also Aerosil, which is obtained by chlorinating ferrosilicon and then hydrolyzing it, but its particles are too fine and it is difficult to use it for the above purpose.

The present inventors conducted intensive research to obtain spherical silica gel of 1 to 60 microns, more preferably 5 to 30 microns, which is a suitable size for makeup cosmetic pigments.
The invention has been completed.

That is, fine spherical sodium silicate is produced by spray drying an aqueous solution containing sodium silicate as a main component represented by NazO.nSiO2.XHzO using a spray dryer.

The particles thus obtained are neutralized with a strong acid such as sulfuric acid or hydrochloric acid, washed with water to remove the soda content, and dried to obtain the desired fine spherical silica gel.

Examples of the sodium silicate aqueous solution used in the present invention include ortho and metasilicate aqueous solutions 1. TIS No.1 and No.2.

No. 3 and No. 4 sodium silicate aqueous solutions and powdered sodium silicate dissolved in water are used.

These may be used alone or in combination, and the higher the soda content, the more porous the resulting silica gel will be.

In addition, aluminum, calcium, magnesilano, etc. can be mixed into these aqueous solutions containing sodium silicate as a main component for the purpose of modifying the obtained particles.

The viscosity of the aqueous solution containing sodium silicate as a main component used in the present invention is usually preferably 1000 P or less; if it exceeds this value, problems such as the particles becoming larger or particles adhering to each other occur.

In the spray drying of the present invention, a well-known spray dryer is usually used.

The spray dryer is preferably a high-speed centrifugal spray method using a rotating disk or a two-fluid nozzle method, and a pressurized nozzle method is not preferred because the particle size becomes too large.

In the case of the rotating disk method, the size of the particles obtained varies depending on the size and rotation speed of the rotating disk, but
The speed at the position where the aqueous solution containing sodium silicate as the main component is ejected from the rotating disk, that is, the circumferential speed of the disk is 70 per minute.
00m or more. If the speed is lower than this, the particles will be large and irregular, making it impossible to obtain the desired particles.

In the case of a two-fluid nozzle system, an aqueous solution containing sodium silicate as a main component is supplied from the center of the nozzle, and compressed air is injected from around the nozzle to atomize it as a mist of sodium silicate. The pressure at this time is preferably in the range of 3 Kt/al to 7 Kp/cl. At pressures below 3 Ky/ct1, particles become large;
7 (If it is fine or fine, it will become too fine and you will not be able to obtain the desired product.

The aqueous solution mainly composed of sodium silicate sprayed in this manner becomes a perfect sphere due to surface tension in the air and is dried.

Next, it is neutralized with this powdered acid. Any acid can be used, such as sulfuric acid, hydrochloric acid, or nitric acid, as long as it reacts with sodium to form a water-soluble salt and can be removed by washing with water.

A strong acid, usually at a concentration of 5 to 10%, is vigorously stirred and the powder is gradually added thereto to neutralize it, and at the same time, sodium becomes a water-soluble salt and exits the powder particles. Thereafter, the desired fine spherical silica gel is obtained through dehydration, water washing, and drying operations.

The particles obtained in this way can be used for make-up cosmetics (
For example, foundation, cream, eye shadow, blush, etc.)
By blending up to 30%, it becomes light, smooth and spreads well, which is unprecedented.

Although the present invention was developed primarily for the purpose of makeup cosmetics, it is of course not limited to this use, and can be applied to silica gel spheres such as plastic fillers, various lubricants, catalyst carriers, and adsorbents for liquid chromatography. It can be used wherever you need it.

This will be explained in more detail with reference to Examples below.

Example-1 A stock solution was prepared by adding 0.5 Kf of water to TIS No. 3 sodium silicate specified in 1408 and 9.59.

The viscosity of the stock solution was 950P.

This stock solution was fed into a rotating disk type spray dryer (body diameter 282 m, height 3 m) at 2 (1/hour), and was sprayed into air at 200°C at a peripheral speed of 7200 m/min. A powder of .3 Kp was obtained.

The obtained powder was introduced into a cyclone from the bottom of the spray dryer and collected.

Next, it was gradually added to a vigorously stirred 10% aqueous sulfuric acid solution 301, and stirring was continued for 10 minutes.

After that, it was dehydrated using a centrifugal dehydrator, washed with water 4 to 5 times until the pH of the filtrate became 7, and dried by heating at 120°C for 3 hours.
A powder of 3 Kp was obtained.

The obtained powder was a true spherical powder with an average particle size of 17 microns, a minimum of 5 microns and a maximum of 50 microns, and had good fluidity and a smooth feel, making it suitable as a makeup pigment.

Example-2 Create a stock solution by adding 8 Ky of water to JIS No. 1 Sodium Silicate 2 KP 1. Ta.

The viscosity of the stock solution was 2CP. This stock solution was transferred to a rotating disk type spray dryer (body diameter: 2.2 m, height: 3 m).
), and the circumferential speed of the rotating disk is 12.
Sprayed into 200t+ air at 000m/mjn, approximately 0
．． Eight powders were obtained.

The obtained powder was introduced into a cyclone from the bottom of the spray dryer and collected.

Next, the mixture was gradually added to 40 g of a vigorously stirred 10% nitric acid aqueous solution, and stirring was continued for 10 minutes.

After that, dehydrate it with a centrifugal dehydrator and 4 to 5 until the pH reaches 7.
Washed with water twice, heated and dried at 120°C for 10 hours, 0.5 Kp
I got a powder.

The obtained powder was a true spherical powder with an average particle size of 7.5 microns, a minimum of 2.5 microns, and a maximum of 23 microns.
It was even smoother and had an excellent feel.

Comparative example-1 JI83 sodium silicate 10Kt was used as the stock solution.

The viscosity of the stock solution was 2200P. This stock solution is placed in a rotating disc type spray dryer (body diameter 2.2m, height 3m) at 20% per hour. The powder was supplied and atomized into air at 20° C. at a peripheral speed of 7000 m/fni, n, to obtain a powder of about 3.5 KF.

The obtained powder was introduced into a cyclone from the bottom of the spray dryer and collected.

Next, it was gradually added to a vigorously stirred 10% aqueous sulfuric acid solution 301 and stirred for 10 minutes.

After that, perform the usual method (dehydration, washing with water, drying for about 2 to 5 minutes)
A powder of Kp was obtained.

The obtained powder was a perfectly spherical powder with an average particle size of 35 microns, a minimum of 10 microns, and a maximum of 70 microns, but the particles were large and irregular, giving it a rough feel, which was not desirable.

Comparative Example-2 A stock solution was prepared by adding 2 kg of water to 8 kg of JI83 sodium silicate.

The viscosity of the stock solution is 40C! It was P.

This stock solution was supplied at 20 J per hour into the spray dryer of Comparative Example-1, and the circumferential speed of the rotating disk was 5000 Vm1n.
The mixture was sprayed into air at 200°C to obtain a powder of approx.

The obtained powder was introduced into a recyclone from the bottom of the spray dryer and collected.

Next, it was gradually added to a vigorously stirred 10% aqueous sulfuric acid solution 301 and stirred for 10 minutes.

Thereafter, it was dehydrated, washed with water, and dried in a conventional manner to obtain a powder with an odor of about 2.2%.

The obtained powder was a perfectly spherical powder with an average particle size of 37 microns, a minimum of 10 microns, and a maximum of 80 microns, but the particles were large and irregular and the feel was not favorable.

Example 3 2 kg of water was added to JI81 Sodium Silicate 8 Ky to prepare a stock solution.

The viscosity of the stock solution was 450P.

Transfer this stock solution to a spray dryer equipped with a two-fluid nozzle (
The powder was sprayed from the bottom to the top of the body (1.8 m in diameter, 3 m in height) at a rate of 10 j/hour to obtain about 49 powders. The spray pressure at this time was 5K9 and the internal temperature was 200C.

The obtained powder was introduced into a cyclone from the bottom of the spray dryer and collected.

Next, gradually add 60% of 10% hydrochloric acid to vigorously stirred solution.
Stirred for 0 minutes.

After that, dehydration, washing, and drying were carried out in the same manner as in Example-1 for about 2 hours.
．． A powder of 5 Ky was obtained.

The obtained powder was a true spherical powder with an average particle diameter of 15 microns, a minimum particle size of 5 microns, and a maximum particle size of 40 microns, and had good fluidity and a smooth feel as in Example-1.

Example 4 A powder foundation was made using the fine spherical silica gel obtained in Example 2.

Ingredient 1. Sericite 40.0 Parts by weight) Talc 83 Mica powder 3D Mica titanium 30 Titanium oxide 190 Yellow iron oxide 30 Bengara ID Black iron oxide 02 Fine spherical silica gel 100 Ingredients 2. Squalane 50 Methylpolysiloxane 30 Isopropyl myristate 20 Paraffin 1.0 Surfactant 1.0 Fragrance 05 First, ingredients 1, sericite, talc, mica powder, titanium mica, yellow iron oxide, Bengara, and black iron oxide, are mixed with Henshil. The mixture was mixed with a mixer and pulverized with an atomizer. Next, fine spherical silica was added and mixed again using a Henshil mixer.

A heated mixture of component 2 was added to the mixture, thoroughly mixed using a Henshil mixer, and the mixture was filled and molded into a medium tray to obtain a powder foundation.

The obtained foundation had excellent spreadability and smoothness compared to the conventional one which did not contain fine spherical silica gel. It also has a light finish with less stickiness.

Patent applicant: Miyoshi Kasei Ltd.

Claims (4)

[Claims] (1) A method for producing fine spherical silica gel, which comprises granulating an aqueous solution mainly composed of sodium silicate represented by NazO-nBio2.XHzO by spray drying, and then neutralizing and removing the soda content with acid. . (2) A method for producing fine spherical silica gel having a particle size of 1 to 60 microns as set forth in claim 1, wherein the aqueous solution containing sodium silicate as a main component used for spray granulation has a viscosity of 1000 P or less. . (3) Spray granulation is a high-speed centrifugal spraying method using a rotating disk (:), and the circumferential speed of the disk is 7000 m/min or more. A method for producing finely kneaded silica gel having a particle diameter of 60 microns. (4) Spray granulation is a two-fluid nozzle method, and the spray pressure is 3 to y.
Particle size 1 to 1 according to claims 1 and 2, characterized in that the particle size is sprayed at an amount of /crI or more and 7 Ky/al or less.
A method for producing fine spherical silica gel having a diameter of 60 microns.