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. 14, 1987
Filed:
Oct. 03, 1986
Applicant:
Inventors:
Assignee:
Diafoil Company, Limited, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
428141 ; 428147 ; 428330 ; 428338 ; 428409 ; 428480 ; 428694 ; 428900 ;
Abstract
A polyester film for magnetic recording media having excellent flatness, slipperiness and adhesiveness of the magnetic layer thereto, said film having minute protrusions on the surface thereof including roughness units each of which consists of a minute protrusion and a recess therearound having a longer diameter of at least 3 .mu.m, wherein the number of the roughness units per square mm, A, (number/mm.sup.2), satisfies the relation (1):