PURPOSE: To decrease the coefft. of friction of a magnetic layer surface and to improve durability and running stability by maintaining the extraction rate of fatty acid by the n-hexane from the magnetic layer contg. magnetic powder, binder component and fatty acid at a specific value.
CONSTITUTION: A magnetic paint contg. the magnetic powder, binder component and fatty acid is coated on a base body and is dried then the coated layer is subjected to a heating treatment for at least ≥3 days at ≥40°C to maintain the extraction rate of the fatty acid by the n-hexane from the magnetic layer always within a 1W200mg/m2 range and to maintain the extraction rate of the fatty acid to be extracted in succession thereto always at ≥8/10 the initial extraction rate. The extraction rate of the fatty acid, for example, stearic acid, etc. remains at the initial rate without change at all after the usable period with the magnetic tape obtd. in such a manner. The fatty is thus bled at the specified rate without change at all for a long period, by which the magnetic recording medium having the excellent running stability and durability is obtd. The clogging, etc. of a magnetic head are not admitted even if said medium is used as a magnetic tape. The magnetic tape having the excellent durability and running stability is obtd.
MIYATA ICHIJI
YOSHIYA MASAYUKI
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