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:
Mar. 31, 1998
Filed:
Mar. 10, 1997
Kouji Kawakita, Joyo, JP;
Seiichi Nakatani, Hirakata, JP;
Tatsuo Ogawa, Amagasaki, JP;
Masatoshi Suehiro, Kyoto, JP;
Kouichi Iwaisako, Uji, JP;
Hideo Akiyama, Kyoto, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A conductive paste compound for via hole filling includes a conductive filler at 80 to 92 weight percent with an average particle size of from 0.5 to 20 .mu.m and specific surface of from 0.1 to 1.5 m.sup.2 / g, a liquid epoxy resin at 4.5 to 20 weight percent containing 2 or more epoxy groups with room temperature viscosity of 15 Pa.sec or less, and a hardener at 0.5 to 5 weight percent, wherein the viscosity is 2,000 Pa.sec or less and the volatile amount is 2.0 weight percent or less. A filling paste and a printed circuit board with use thereof are provided which can conduct an inner-via-hole connection between electrode layers without using a through-hole plating technique. The conductive paste comprises a metallic particle such as copper, an epoxy resin, a hardener, and if necessary, a dispersant. The paste having low viscosity and low volatility under high shear is used to fill holes disposed in a laminated substrate. Then, this substrate is heated and pressurized together with copper foil on both sides to attain a printed circuit board where both sides are electrically inner-via-hole connected.