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:
Apr. 30, 1985
Filed:
Apr. 11, 1984
Applicant:
Inventors:
Assignee:
Toray Industries, Inc., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
428141 ; 360134 ; 360135 ; 360136 ; 427128 ; 427131 ; 428143 ; 428172 ; 428212 ; 428216 ; 428220 ; 428332 ; 428335 ; 428336 ; 428480 ; 428483 ; 428533 ; 428694 ; 428695 ; 428900 ; 428910 ;
Abstract
A magnetic recording disk is disclosed, which comprises (1) a three-layered laminate consisting of a core layer of a biaxially oriented polyolefin film which has a birefringence of not more than 0.01 and an amorphous-region orientation coefficient of not more than 0.2 and two outer layers of a biaxially oriented polyester film adhereed to the core layer, and (2) a magnetic layer formed on at least one side of the laminate. This magnetic recording disk undergoes only a slight dimensional change with a variation in humidity and temperature, and the dimensional change is isotropic in the plane.