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:
Aug. 21, 1984
Filed:
Apr. 22, 1983
John C Ottman, San Jose, CA (US);
John C Shen, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The disclosure is directed to a method and apparatus for superfinishing magnetic disk substrates using a non-friable polishing pad including a high density polyurethane foam binder in which at least 50 per cent by weight of classified hard particles are retained. Polishing occurs by rotating the pad against the surface to be ultrafinished in the presence of a water soluable liquid vehicle maintaining a minimum pressure of 5 pounds per square inch at a rotational speed that achieves the desired aggressiveness of the polishing media. The method and apparatus contemplate both the ultrafinishing of newly prepared substrate disks and the restoring of previously coated disks to a ultrafinished substrate condition without producing substances or conditions toxic to the ecology or the operator.