METHOD FOR COATING CARRIER

摘要

PROBLEM TO BE SOLVED: To efficiently obtain resin coated carrier core particles at a low cost in the form of low porosity mechanically strong coated fine particles while using high porosity brittle core particles by blending 1st coated fine particles with a 2nd coating resin or resin Mixture and heating the blend to prepare 2nd coated fine particles or fine particles coated twice. SOLUTION: Core particles are blended with a 1st coating resin or resin mixture to prepare a 1st blend and the 1st blend is heated to prepare 1st coated particles. The 1st coated particles are blended with a 2nd coating resin or resin mixture to prepare a 2nd blend and the 2nd blend is heated to prepare 2nd coated particles or particles coated twice. The 1st coating resin is, e.g. a crosslinkable thermosetting resin such as polyurethane, polyester or a mixture of them. The 2nd coating resin is a polymer capable of imparting mechanical stability so as to make the core particles mechanically strong or a mixture of such polymers.