The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 12, 1994
Filed:
Dec. 23, 1992
Hideshi Kurihara, Sagamihara, JP;
Masahito Satoh, Sagamihara, JP;
Tsuyoshi Nagai, Sagamihara, JP;
Sadayoshi Miura, Yamato, JP;
Toshifumi Osawa, Hachioji, JP;
Teijin Limited, Osaka, JP;
Abstract
There is provided a polyester film useful for production of a magnetic recording medium excellent in runnability, electromagnetic conversion characteristics and storage stability. In the polyester film, a continuous thin film which contains a resin as a matrix and acts as a primer layer for a magnetic layer is coated on one surface of a support film composed of a polyester. According to one embodiment thereof, the surface of the continuous thin film has (A) small protuberances each containing particles with an average particle size of less than 0.06 micrometer as a nucleus and having a height of 13 nm or less, (B) large protuberances each containing particles with an average particle size of 0.06 micrometer or more as a nucleus and having a height of 30 nm or less, and (C) micro-protuberances composed of a matrix resin alone, the numbers, per mm.sup.2 of the film, of these protuberances satisfying the formulas,