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:
Oct. 10, 1995
Filed:
Mar. 05, 1993
Yoshiharu Waki, Chigasaki, JP;
Masayasu Fujisawa, Kanagawa, JP;
Shigeo Aikawa, Yokohama, JP;
Kenya Ohashi, Hitachi, JP;
Yukihiro Isono, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
This invention provides a lap capable of reducing the pole recession produced between the substrate and the magnetic film when the air-bearing surface of a thin-film magnetic head is lapped, a lapping liquor used for such lapping, and a thin-film magnetic head having its air-bearing surface lapped by using them. Lapping is carried out by using a lap made of a material having both a phase of tin and a phase of brass with a greater rigidity in supporting the abrasive grains than tin, and a lapping liquor prepared by mixing an anionic surfactant (15) and an ampholytic surfactant (16). According to the present invention, it is possible to reduce the pole recession in the thin-film magnetic heads and to accordingly shorten the recording bit length of the magnetic discs.