Method for producing liquid dispersion of ceramic microparticles

Patent metadata

Field	Value
Publication number	US-10322975-B2
Application number	US-201314771546-A
Country	US
Kind code	B2
Filing date	Mar 1, 2013
Priority date	Mar 1, 2013
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

The present invention provides a method for producing a dispersion of fine ceramic particles, the method comprising: adding fine ceramic particles having a mean particle size of less than 1 μm to a dispersion medium selected from the group consisting of a lower alcohol and water; and dispersing the fine ceramic particles in the dispersion medium using a rotor-stator homogenizer. The present invention enables the production of a highly homogeneous and stable dispersion of a nanosized ceramic powder, which is prone to aggregation and the homogeneous dispersion of which is difficult to form, by conducting a simple, uncomplicated operation.

First claim

The invention claimed is:

1. A method for producing a dispersion of fine ceramic particles, the method comprising:
adding fine ceramic particles having a mean particle size of less than 1 μm to a lower alcohol dispersion medium; and
dispersing the fine ceramic particles in the dispersion medium using a rotor-stator homogenizer;
wherein said fine ceramic particles are either fine silicon carbide particles or fine boron nitride particles, said fine ceramic particles have a mean particle size of 300 nm or less and said fine ceramic particles are dispersed while the temperature of the dispersion is being controlled to 40° C. or less and wherein the step of dispersing is conducted using said rotor-stator homogenizer at a rotation speed within the range of 500 to 2500 rpm.

2. The method for producing a dispersion of fine ceramic particles according to claim 1 , wherein the lower alcohol is isopropyl alcohol.

3. A method for producing a dispersion of fine ceramic particles, the method comprising:
adding fine ceramic particles having a mean particle size of less than 1 μm to a water dispersion medium; and,
dispersing the fine ceramic particles in the dispersion medium using a rotor-stator homogenizer;
wherein the fine ceramic particles are either fine silicon carbide particles or fine boron nitride particles, the fine ceramic particles having a mean particle size of 300 nm or less;
wherein the pH of the dispersion is not less than 2, and,
wherein the fine ceramic particles are dispersed in the presence of a polymeric dispersant containing cationic groups and wherein the step of dispersing is conducted using said rotor-stator homogenizer at a rotation speed within the range of 500 to 2500 rpm.

4. The method according to claim 3 , wherein the dispersion has a pH of 2 to 9.

5. The method according to claim 3 , wherein the polymeric dispersant is polyethylenimine.

6. The method according to claim 3 , wherein the fine ceramic articles are dispersed in the presence of both the polymeric dispersant and a surfactant.

7. The method according to claim 6 , wherein the surfactant is a nonionic surfactant.

8. The method according to claim 6 , wherein the surfactant is an alkyl glycoside.

9. The method according to claim 1 , wherein the rotation speed is within the range of 500 rpm to less than 3,200 rpm.

10. The method according to claim 3 , wherein the rotation speed is within the range of 500 rpm to less than 3,200 rpm.

Assignees

• Univ Kyoto

Inventors

• Hinoki Tatsuya
• Shimoda Kazuya

Classifications

• C01P2006/12

  Surface area · CPC title

• C01P2004/52

  highly monodisperse size distribution · CPC title

• C01P2006/22

  Rheological behaviour as dispersion, e.g. viscosity, sedimentation stability · CPC title

• C01P2006/10

  Solid density · CPC title

• C04B35/565

  based on silicon carbide · CPC title