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:
Feb. 21, 1995
Filed:
May. 25, 1994
Applicant:
Inventors:
Naoyuki Goto, Sagamihara, JP;
Katsuhiko Yamaguchi, Sagamihara, JP;
Assignee:
Kabushiki Kaisya Ohara, Kanagawa, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C03C / ; C03C / ;
U.S. Cl.
CPC ...
501-4 ; 501-6 ; 501 63 ;
Abstract
A glass-ceramic for a magnetic disk substrate in which the grain size can be controlled and the surface roughness after polishing is within the range from 15 .ANG. to 50 .ANG. is provided by heat treating a base glass including in weight percent: