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:
Mar. 11, 1997
Filed:
Feb. 22, 1996
Ken Ishitobi, Shiojiri, JP;
Showa Denko K.K., Tokyo, JP;
Abstract
The composition for texturing a magnetic disk contains 0.1-5 weight %, based on the composition, of polycrystalline sintered alumina abrasives in a grinding fluid, the abrasives being produced by a sol-gel method comprising the steps of mixing a slurry of alumina hydrate with a dilute acid for solation, mixing the resultant alumina hydrate sol with a seed and/or a modifier, drying said alumina hydrate sol at 50.degree.-120.degree. C. for gelation, pulverizing and classifying the resultant gel, calcinating said gel at 400.degree.-900.degree. C., sintering the calcinated alumina particles at 1100.degree.-1400.degree. C., and pulverizing and classifying the resultant sintered alumina particles to a maximum particle size of 5 .mu.m or less and an average particle size of 0.1-3 .mu.m.