Magnetic recording medium

- Fuji Photo Film Co., Ltd.

A magnetic recording medium comprises a non-magnetic support having provided thereon a lower magnetic layer having a thickness of 2.5 .mu.m or higher and an upper magnetic layer having a thickness of 2 .mu.m or lower in this order, wherein both the upper and lower magnetic layers contain ferromagnetic particles, and the lower magnetic layer contains carbon black having an average primary particle diameter of less than 20 .mu.m in the amount of from 1.0 to 20 parts by weight per 100 parts by weight of the ferromagnetic particles contained in the lower magnetic layer, and the upper magnetic layer contains carbon black having an average primary particle diameter of at least 40 .mu.m but less than 80 .mu.m in an amount of from 0.1 to 10.0 parts by weight per 100 parts by weight of the ferromagnetic particles contained in the upper magnetic layer, but less than the amount of carbon black used in the lower magnetic layer.

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Claims

Referenced Cited
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Foreign Patent Documents
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63-259826 October 1988 JPX
Patent History
Patent number: RE36271
Type: Grant
Filed: Jun 24, 1992
Date of Patent: Aug 17, 1999
Assignee: Fuji Photo Film Co., Ltd. (Kanagawa)
Inventors: Hiroo Inaba (Kanagawa), Shinji Saito (Kanagawa), Hiroshi Ogawa (Kanagawa)
Primary Examiner: Stevan A. Resan
Law Firm: Sughrue, Mion, Zinn, Macpeak & Seas, PLLC
Application Number: 7/903,353