Black paint using magnetic iron oxide particles have been surface treated and magnetic iron oxide particles whose surface has been treated, a rubber-resin composition

摘要

PROBLEM TO BE SOLVED: To provide surface-treated magnetic iron oxide particle powder the agglomerated particle of which has small particle size and which exhibits excellent dispersibility in toluene and is used suitably for producing a black coating material and a rubber-resin composition.;SOLUTION: The surface-treated magnetic iron oxide particle powder, which is obtained by coating the surface of a magnetic iron oxide particle with a specified silane coupling agent by 4-16 μmol/m² and which has 0.05-0.70 μm average particle diameter, can be obtained by hydrophobizing the magnetic iron oxide particle to be a core in an aqueous medium, drying the hydrophobized magnetic iron oxide particle in a fluidized bed and heat-treating the dried hydrophobized magnetic iron oxide particle, or can be obtained by hydrophobizing the magnetic iron oxide particle to be the core in a wheel type kneader or a grinder and simultaneously heat-treating and grinding the hydrophobized magnetic iron oxide particle together with media such as balls in a dyer having a vibrating mechanism.;COPYRIGHT: (C)2010,JPO&INPIT