Non-magnetic composite particles, process for producing the same and magnetic recording medium using the same

摘要

Non-magnetic composite particles composed of non-magnetic core particles having an average particle size of 0.01 to 0.3 mum, and inorganic fine particles having an average particle size of 0.001 to 0.07 mum. The fine particles are present in an amount of 0.1 to 20% by weight based on the weight of the non-magnetic particles are on the surface of each non-magnetic particle, and are fixed or anchored on the surface of each non-magnetic particle through a silicon compound.The non-magnetic composite particles have a high polishing effect and a high dispersibility, and are useful as a non-magnetic undercoat layer for a magnetic recording medium.