Patent ID: 6667120
Filing Date: 2003-12-23
Classification: G11B,Y10T

Abstract:
A magnetic recording medium comprising: a non-magnetic base film;a non-magnetic undercoat layer formed on the non-magnetic base film, comprising non-magnetic acicular composite particles and a binder resin; and a magnetic recording layer formed on the non-magnetic undercoat layer, comprising magnetic particles and a binder resin, said non-magnetic acicular composite particles having an average major axis diameter of 0.01 to 0.3 &mgr;m and comprising: acicular hematite particles or acicular iron oxide hydroxide particles as non-magnetic core particles, a coating formed on surface of said acicular hematite particle or acicular iron oxide hydroxide particle, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtainable from alkoxysilane compounds, and (2) polysiloxanes or modified polysiloxanes, and a phthalocyanine-based pigment coat formed on said coating layer comprising said organosilicon compound, in an amount of from 1 to 100 parts by weight based on 100 parts by weight of said acicular hematite particles or acicular iron oxide hydroxide particles.