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:
May. 05, 1998
Filed:
Feb. 12, 1997
Applicant:
Inventors:
Toshinobu Miyakoshi, Chiba, JP;
Hiroaki Hasegawa, Chiba, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
C03C / ; C03C / ;
U.S. Cl.
CPC ...
501 32 ; 501 66 ; 501 67 ; 501 69 ; 501 70 ; 501 72 ;
Abstract
A borosilicate glass composition comprising 55-67 mol % of SiO.sub.2, 3-11 mol % of Al.sub.2 O.sub.3, 16-26 mol % of B.sub.2 O.sub.3, and 3-11 mol % of at least one oxide of SrO, CaO, MgO and ZnO is useful in the preparation of ceramic substrates. Since the amount of orthoboric acid formed on the glass in contact with humid air is minimized, the glass gives rise to little trouble in the manufacture of ceramic substrates. Ceramic compositions using the glass and a filler can be fired at low temperatures into sintered substrates which are characterized by a low dielectric constant, low dielectric dissipation factor, and high flexural strength.