PURPOSE: To safely and surely disperse ceramic powder scarcely using dispersant by using as dispersing medium one of super pure water with electric resistance over a specific value or a degased water with dissolved oxigen below a specific value and electric resistance over a specific value.
CONSTITUTION: Either of super pure water with electric resistance over 170MΩ or degased water with dissolved oxigen concentration below 10ppm and electric resistance over 1MΩ is used as a dispersing medium. The ceramic powder to be dispersed is not limited to a specific material if only it does not elude metal ion when dispersed in water. For example, such non-oxide ceramics as siliconcarbide, siliconnitride, etc., are preferable. The super pure water has little conductive material ion, and therefore has high electric resistance and small surface tension. Thus, the material causing aggregation and gas molecules adsorbed on powder surface are ioninzed, wettability of the powder is improved and stable dispersion is realized. Also, for the specific degased water, similar effect to the super pure water is expected.
KAKO KOJI
ITO WATARU
