# US 4,395,466 A · Magnetic recording medium

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- Number: US 4,395,466 A
- Document ID: US4395466A
- Status: Granted
- Kind: A
- Application number: 06/265,492
- Filed: 1981-05-20
- Granted: 1983-07-26
- Earliest claimed: 1980-05-21
- Assignees: Fuji Photo Film Co., Ltd.
- Inventors: Hiroshi Ogawa; Yasuo Tamai
- Web page: https://patentgrep.com/patent/US4395466A

## CPC

- G11B 5/71: characterised by the lubricant
- Y10S 428/90: Magnetic feature
- Y10T 428/25: Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A magnetic recording medium comprising a non-magnetic base which has formed thereon a magnetic layer made of a binder and fine ferromagnetic particles dispersed therein is disclosed. The magnetic layer is characterized by containing a mineral oil having a viscosity of 300 cs or less at 37.8.degree. C. and an aliphatic acid having 12 to 22 carbon atoms.

## Claims

### Claim 1

A magnetic recording medium, comprising:
a non-magnetic base;
a magnetic layer formed on said base; said magnetic layer consisting essentially of a binder and fine ferromagnetic particles dispersed within said binder, a mineral oil having a viscosity of 300 cs or less at 37.8.degree. C. contained in said magnetic layer an an amount of 0.05 weight percent to 1 weight percent, and an aliphatic acid having 12 to 22 carbon atoms contained in said magnetic layer in an amount of about 0.2 weight percent to 5.0 weight percent, based on the weight of the fine ferromagnetic powder.

### Claim 2 (depends on 1)

A magnetic recording medium as claimed in claim 1 wherein said mineral oil is contained in said magnetic layer in an amount of between 0.1 weight percent to 1.0 weight percent based on the weight of the fine ferromagnetic powder, and said aliphatic acid is contained within said magnetic layer in an amount of between 0.5 weight percent to 3.0 weight percent.

### Claim 3 (depends on 1)

A magnetic recording medium as claimed in claim 1, further comprising a dispersant, an abrasive, and carbon.