PRODUCTION OF KAOLIN FOR COATING

摘要

PURPOSE:To obtain good kaolin for coating to which the increase of viscosity of coating liquid is not caused without breaking the crystal of kaolin by grinding kaolin specified in the range of mean particle diameter by means of a wet ball mill or a media agitating mill used with synthetic resin beads. CONSTITUTION:Kaolin having 1.5-6mum mean particle diameter is ground in a wet method with a wet ball mill or a media agitating mill such as an atomizer used with synthetic resin beads consisting of nylon and PE or the like preferably having 50-120 M Rockwell hardness. In this case, polycarboxylic acid contg. a polymer of acrylic acid is used in the dispersion of kaolin. When kaolin is treated so that mean particle diameter after grinding treatment is regulated to 0.8mum or more especially to a range within 1.0-1.8mum, good kaolin for coating is obtained.