KR20000004077A - Production method of corpuscle of hollow-shaped inorganic oxide - Google Patents

Abstract

PURPOSE: A production method of corpuscles of a hollow-shaped inorganic oxide is provided to make more than a specific size of hollow-shaped inorganic oxide corpuscle. CONSTITUTION: A production method of a corpuscle of a hollow-shaped inorganic oxide has the steps of: dissolving a nonionic surface active agent in nonpolar organic solvent; adding sodium silicide and agitating with a high-speed blender to make liquid solution; adding the produced liquid solution in bicarbonate ammonium solution or carbonate ammonium solution and mixing or making a corpuscle of 0.5-20um size by reacting with foaming the gas of carbon dioxide; washing the corpuscle with water and alcohol and drying.

Description

Method for producing the inorganic oxide fine particles in the hollow form

The present invention relates to a method for producing the inorganic oxide fine particles in the hollow form.

More specifically, the silicate of sodium _{(Na 2 O · nSiO 2 ·} mH 2 O, 1≤n≤3, 5≤m≤7) and to the non-ionic surfactant and the emulsion (emulsion) with a non-polar organic solvent yield It relates to a method for producing the fine particles by particle size (0.5 to 20 μm).

Inorganic oxide fine particles in the hollow form have high slipperiness and are used for make-up of cosmetics, and are used as a base of powder supporting silver and various functionalities.

As a conventional manufacturing method, the method of hydrolyzing and manufacturing an organometallic compound at the time of preparation of the said inorganic oxide fine particle is generally used.

Japanese Patent Laid-Open No. 63-182204 discloses a method for producing hydrate fine particles by hydrolyzing a hydrolyzable organometallic compound in an aqueous solution containing alcohol.

The hydrolysis method which is the manufacturing method of the conventional hydrate fine particles is as follows.

nSi (OR) ₄ + 2nH ₂ O → nSiO ₂ + 4nROH

In the reaction mechanism, in order to control the size and shape of the particles, it is difficult to control the temperature because the concentration of the organometallic compound, the alcohol, the water, and the catalyst is controlled to control the temperature.

However, the manufacturing method has various problems.

The first of these problems is the high price of the organometallic compound used as a raw material.

The second is that organometallic compounds react sensitively with moisture in the air and thus are not easy to store and handle, and these problems can cause many problems in manufacturing and also have process limitations.

Third, since it takes a considerable time to produce oxide fine particles of a certain size (0.7㎛) or more, there is a problem that it is difficult to increase the production.

The present inventors have intensively researched to solve such problems in the related art, and as a result, the inorganic metal oxide and nonionic surfactant different from the organometallic compound which is a raw material that has been used in the past during the production of the inorganic oxide fine particles in the hollow form The present invention has been found to be able to solve the problem of manufacturing cost, the problem of manufacturing process, and the yield of the conventional method by manufacturing using the present invention.

Accordingly, an object of the present invention is to provide a method of manufacturing inorganic oxide fine particles having a predetermined size or more and capable of solving problems in the manufacturing process.

The present invention relates to a method for producing the inorganic oxide fine particles in the hollow form. More specifically, a nonionic surfactant is dissolved in a nonpolar organic solvent, and sodium silicate (Na ₂ O.nSiO ₂ · mH ₂ O, 1 ≦ n ≦ 3, 5 ≦ m ≦ 7) is added to the solution to form a high speed stirrer. After stirring, the resultant emulsion droplets were added to an ammonium bicarbonate solution or an ammonium carbonate solution and stirred or the carbon dioxide gas was bubbled to complete the reaction. The present invention relates to a method for preparing particulates by washing and drying with a furnace.

Sodium silicate (Na ₂ O · nSiO ₂ · mH ₂ O, 1 ≤ n ≤ 3, 5 ≤ m ≤ 7) added in the above may be used in 10 to 60% by weight based on the total composition, the nonionic surfactant 0.1 to 10% by weight and the remaining weight percent non-polar organic solvent may be used, the particle size of the final fine particles can be determined according to the stirring speed and time. That is, increasing the stirring speed can produce a large number of fine particles while having a small particle size, and decreasing the stirring speed can obtain a small number of fine particles although the size of the fine particles is large.

In the present invention, the nonionic surfactant functions to disperse an aqueous sodium silicate solution in a nonpolar organic solvent to form a micellar for preparing small droplets, that is, when water is dropped into oil, It helps to form microcapsules, where a non-polar organic solvent acts as an oil. Therefore, the sodium silicate aqueous solution forms small droplets by the nonionic surfactant and is emulsified in the nonpolar organic solvent.

As the nonionic surfactant used in the present invention, for example, a fatty acid sorbitan ester compound having 8 to 22 carbon atoms or a fatty acid sorbitan ester compound having 8 to 22 carbon atoms to which 1 to 40 mol of ethylene oxide is added It is possible to use, wherein the fatty acid is a mixture of poly-, mono-, di-, tri-fatty acid.

As the nonpolar organic solvent used in the present invention, an aromatic or aliphatic organic solvent can be used, for example, toluene, n-nucleic acid, benzene, isopropyl alcohol, and the like.

In the present invention, a mixture of nonionic surfactant and sodium silicate dissolved in a nonpolar organic solvent is stirred with a high speed stirrer to prepare an emulsion droplet, and then added to an ammonium bicarbonate solution, wherein ammonium bicarbonate is used to prepare silicon oxide (SiO ₂ ) fine particles. It is used for, and the reaction at this time is expressed as follows.

Na ₂ O⋅nSiO ₂ + NH ₄ HCO ₃ → nSiO ₂ + Na ₂ CO ₃ + NH ₄ OH

Hereinafter, the preparation method according to the present invention in detail as follows.

Example 1

5 g of sorbitan monostearate was dissolved in 300 ml of kerosene, a non-polar organic solvent, and sodium silicate (Na ₂ O.SiO ₂ .5H ₂ O 100 g) was added. The mixture was stirred for 30 minutes with a high speed stirrer, and then added to 600 g of ammonium bicarbonate solution and stirred for 30 minutes. The obtained product was filtered, washed with water and alcohol and dried to prepare silicon oxide (SiO ₂ ) fine particles.

Example 2

In the same manner as in Example 1, instead of only 5 g of sorbitan monostearate, microparticles were prepared by adding 7 mol of ethylene oxide to 5 g of sorbitan monostearate, a nonionic surfactant.

Example 3

The fine particles were prepared in the same manner as in Example 1, using 600 g of ammonium carbonate solution instead of only 600 g of ammonium bicarbonate.

Example 4

As in Example 1, except that only 600 g of ammonium bicarbonate was bubbled using carbon dioxide gas to prepare microparticles.

The hollow particles prepared by the method as described above are prepared using a nonpolar organic solvent and a nonionic surfactant instead of the organometallic compound, so they are sensitive to the production costs and moisture which are problematic when using the organometallic compound. In addition to solving the problem of reactivity, it is possible to produce a large number of oxide fine particles of a certain size (0.7㎛) or more in a short time, which is effective to increase the production, for example, when producing 0.5㎛ SiO2 fine particles by the conventional hydrolysis method While less than 5%, the yield is more than 40% when manufactured by the emulsified invention.

According to the present invention, the fine particles produced by the method for producing the inorganic oxide fine particles in the hollow form can solve the problems posed above, that is, the problems of productivity and manufacturing safety.

Claims (4)

A nonionic surfactant is dissolved in a nonpolar organic solvent, and sodium silicate (Na ₂ O.nSiO ₂ · mH ₂ O, 1 ≦ n ≦ 3, 5 ≦ m ≦ 7) is added to the solution, followed by stirring with a high speed stirrer to emulsify it. Preparing droplets, adding the prepared emulsion droplets to an ammonium bicarbonate solution or an ammonium carbonate solution to stir or reacting by evaporating carbon dioxide gas to produce fine particles having a particle size of 0.5 to 20 μm, Method for producing an inorganic oxide fine particles of the hollow form, characterized in that consisting of washing and drying with water and alcohol. The method of claim 1, wherein the nonpolar organic solvent is selected from the group consisting of an aromatic organic solvent or an aliphatic organic solvent. The nonionic surfactant according to claim 1, wherein the nonionic surfactant comprises one of a fatty acid sorbitan ester compound having 8 to 22 carbon atoms or a fatty acid sorbitan ester compound having 8 to 22 carbon atoms to which 1 to 22 mol of ethylene oxide is added. A method for producing the inorganic oxide fine particles in the hollow form, characterized in that it is selected and used. 4. The method of claim 3, wherein the fatty acid is a mixture of poly-, mono-, di-, tri-fatty acids.