Magnetic recording medium
AssigneeFuji Photo Film Co., Ltd.
InventorsKoji Naoe, Kiyomi Ejiri
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Abstract
Provided is a magnetic recording medium exhibiting a high C/N (low noise) ratio in high-density magnetic recording. A magnetic recording medium which comprises a nonmagnetic lower layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder provided in this order on a flexible nonmagnetic support. The nonmagnetic lower layer comprises flat acicular α-iron oxide powder with a major axis length ranging from 0.05 to 0.5 μm and a ratio of the major width to the minor width (major width/minor width) of the minor axis cross-section when sectioned at an angle perpendicular to the major axis is equal to or higher than 1. The granular nonmagnetic particles have a mean particle diameter equal to or less than 0.04 μm.
Claims11
A magnetic recording medium which comprises a nonmagnetic lower layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder provided in this order on a flexible nonmagnetic support,
- wherein said nonmagnetic lower layer comprises flat acicular α-iron oxide powder and granular nonmagnetic particles and said flat acicular α-iron oxide powder has a major axis length ranging from 0.05 to 0.5 μm and a ratio of the major width m to the minor width k of the minor axis cross-section when sectioned at an angle perpendicular to the major axis (m/k) being higher than 1, and said granular nonmagnetic particles have a mean particle diameter equal to or less than 0.04 μm.
Dependencies are inferred from the claim text.