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:
Feb. 27, 2001
Filed:
Nov. 12, 1998
Norihiko Ikai, Komaki, JP;
Hiroshi Sumi, Ichinomiya, JP;
Masahiko Okuyama, Nagoya, JP;
Toshifumi Kojima, Komaki, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
A paste for filling through-holes of a printed wiring board contains 100 parts by weight of an epoxy resin composition containing 90 to 99.5 parts by weight of an epoxy resin and 0.5 to 10 parts by weight of a curing agent; and (B) 500 to 1000 parts by weight of a metallic filler having an average particle size of 0.5 to 20 &mgr;m. The paste has a viscosity of not higher than 20,000 poise at 25° C. and a volatile content of not more than 1.0% when heated in a filling step. The paste exhibits such shrink-resistance properties that when a first cured resin obtained by heating in a filling step is re-heated and cooled in a solder reflow step to obtain a second cured resin, the shrinkage percentage of the first cured resin to the second cured resin in the longitudinal direction of the through-hole is not greater than 0.1%.