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. 02, 1979
Filed:
Sep. 18, 1978
Applicant:
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
360120 ; 29603 ;
Abstract
A magnetic head having a sputter-deposited glass film of the gap forming area of the magnetic core, said glass film being made of borosilicate glass having the composition consisting of 65-85 mol % of SiO.sub.2, 8-30 mol % of B.sub.2 O.sub.3 and containing 2-15 mol % of alkali metal oxide Na.sub.2 O and K.sub.2 O and 0.1-5 mol % of Al.sub.2 O.sub.3, with the molar ratio of boron oxide to alkali metal oxides being defined by the following formula: ##EQU1## The magnetic head provides sharpness of the recording leakage flux, thus giving excellent electromagnetic conversion characteristics.