Claims
- 1. In a magnetic recording medium comprising a non-magnetic support and a magnetic recording layer provided on said support, the improvement wherein said magnetic recording layer comprises:
- a ferromagnetic metal powder having a specific surface area of not less than 40 m.sup.2 /g;
- a fatty acid having a melting point of lower than 50.degree. C. which is oleic or lauric acid;
- a fatty acid having a melting point of not lower than 50.degree. C. which is stearic acid;
- a fatty acid ester which is butyl stearate; and
- carbon black powder having a mean particle size of 60-120 .mu.m and a dibutyl phthalate-absorbing capacity of not more than 100 ml/100 g in an amount of not more than 10% by weight based on the amount of the ferromagnetic metal powder;
- the total amount of the two fatty acids and the fatty acid ester being in the range of 1 to 10% by weight based on the total amount of the ferromagnetic metal powder, wherein the total amount of the two fatty acids is in the range of 1 to 80% by weight based on the amount of the two fatty acids and the fatty acid ester, wherein the ratio of the fatty acid having a melting point of lower than 50.degree. C. to the fatty acid having a melting point of not lower than 50.degree. C. is in the range of 1/10 to 10/1.
- 2. The magnetic recording medium as claimed in claim 1, wherein the dibutylphthalate-absorbing capacity of the carbon black powder ranges from 40 to 80 ml/100 g.
- 3. The magnetic recording medium as claimed in claim 1, wherein said magnetic recording layer contains an abrasive selected from the group consisting of .alpha.-Fe.sub.2 O.sub.3, .alpha.-Al.sub.2 O.sub.3, and Cr.sub.2 O.sub.3.
- 4. The magnetic medium as claimed in claim 1, wherein the total amount of fatty acids and fatty ester is 2 to 8%, and the total amount of the two fatty acids is 20 to 60% of the total amount of fatty acids and fatty acid ester.
- 5. The magnetic medium as claimed in claim 1, in which the ferromagnetic metal powder has a specific surface area of not less than 45 m.sup.2 /g.
- 6. The magnetic recording medium as claimed in claim 5, wherein the total amount of the two fatty acids is in the range of 20 to 60% by weight based on the amount of the two fatty acids and the fatty acid ester.
Priority Claims (2)
Number |
Date |
Country |
Kind |
59-268083 |
Dec 1984 |
JPX |
|
59-268084 |
Dec 1984 |
JPX |
|
Parent Case Info
This is a continuation of application Ser. No. 810,251 filed on Dec. 17, 1985 now abanoned.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1946554 |
Mar 1971 |
DEX |
0138726 |
Jul 1985 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
810251 |
Dec 1985 |
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