Method for producing silica-zirconia composite particles each coated with silica layer

A technology of silicon dioxide and manufacturing method, applied in the directions of silicon dioxide, zirconia, silicon oxide, etc., can solve the problem of difficulty in obtaining monodispersity, and achieve the effect of excellent X-ray contrast.

CN102471077AActive Publication Date: 2012-05-23TOKUYAMA DENTAL CORP
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2012-05-23

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Abstract

Disclosed is a method for producing silica-zirconia composite oxide particles each coated with a silica layer, which is characterized in that a liquid dispersion of silica-zirconia composite oxide particles is obtained by reacting an alkoxide of silicon and / or a condensable compound derived from the alkoxide with an alkoxide of zirconium and / or a condensable compound derived from the alkoxide in a water-containing solvent that contains acetonitrile so that the reaction liquid is to contain not less than 10% by mass of acetonitrile, and then the surface of each silica-zirconia composite oxide particle is coated with a silica layer by reacting the silica-zirconia composite oxide particles dispersed in the liquid dispersion with an alkoxide of silicon and / or a condensable compound derived from the alkoxide in the liquid dispersion of silica-zirconia composite oxide particles.
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Description

technical field

[0001] The present invention relates to a method for producing silica-zirconia composite particles (hereinafter sometimes simply referred to as composite layered particles) having a surface coated with a silica layer. According to this production method, composite layered particles with good monodispersity can be produced under stable production conditions. Background technique

[0002] A method of producing spherical silica particles with high monodispersity by hydrolyzing and polycondensing alkoxides such as silicon is known. A method of producing metal oxide particles by polycondensing the raw material in an aqueous solvent using an organometallic compound such as a metal alkoxide as a raw material is generally called a sol-gel method. Silica-based composite oxide particles can be produced by a sol-gel method by using silicon alkoxide and metal alkoxide other than silica as primitives. Examples of the silica-based composite oxide particles include partic...

Examples

Embodiment 1

[0127] (Preparation of alkoxide solution for composite oxide particles)

[0128] 356 g of tetraethoxysilane (Colcoat Co., Ltd.) and 427 g of isobutanol were added to a 2-liter Erlenmeyer flask and stirred. 8.9 g of 0.06% by mass of dilute sulfuric acid was added thereto, followed by stirring for 17 hours to perform partial hydrolysis of tetraethoxysilane. Then, 114 g of tetrabutyl zirconate (Honking Chemical Industry Co., Ltd., trade name: HZ-NB) and 17.3 g of 28% sodium methoxide (Wako Pure Chemical Industries, Ltd.) were added to the obtained reaction liquid to obtain a colorless and transparent compound Alkoxide solution for oxide particle production.

[0129] (Manufacture of silica-zirconia composite oxide particles)

[0130] 370 g of acetonitrile, 107 g of isobutanol, and 260 g of aqueous ammonia (25% by mass) were charged into a jacketed glass reactor having a stirring blade and an inner volume of 3 liters. The temperature of the circulating water in the jacket was se...

Embodiment 2

[0138] (Preparation of alkoxide solution for composite oxide particle production)

[0139] 786 g of tetraethoxysilane (Colcoat Co., Ltd.) and 444 g of isobutanol were added to a 3-liter Erlenmeyer flask, and stirred. Furthermore, 22.2 g of 0.06 mass % dilute sulfuric acid was added, and the partial hydrolysis of tetraethoxysilane was performed for 17 hours. Then, 228 g of tetrabutyl zirconate (Honking Chemical Industry Co., Ltd., trade name: HZ-NB) and 34.6 g of 28% sodium methoxide (Wako Pure Chemical Industries, Ltd.) were added to the obtained reaction solution to obtain a colorless and transparent compound Alkoxide solution for oxide particle production.

[0140] (Manufacture of silica-zirconia composite oxide particles)

[0141] 300 g of acetonitrile and 280 g of aqueous ammonia (25% by mass) were respectively charged into a jacketed glass reactor having a stirring blade and an internal volume of 3 liters. The temperature of the circulating water in the jacket was set ...

Embodiment 3

[0149] (Preparation of alkoxide solution for composite oxide particles)

[0150] The same alkoxide solution for producing complex oxide particles as that used in Example 1 was used.

[0151] (Manufacture of silica-zirconia composite oxide particles)

[0152] 477 g of acetonitrile and 260 g of aqueous ammonia (25% by mass) were charged into a jacketed glass reactor having a stirring blade and an internal volume of 3 liters. The temperature of the circulating water in the jacket was set at 40°C. The stirring blade was rotated at 180 rpm to stir the inside of the reactor. 923.2 g (total amount) of the aforementioned alkoxide solution for producing complex oxide particles prepared in advance was supplied into the reaction solvent over 7 hours, and stirred for 20 minutes after the supply.

[0153] Through the above reaction, a silica-zirconia composite oxide particle dispersion liquid was obtained. The particle concentration was 11% by mass. The result of evaluating the disper...