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:
Aug. 29, 1995
Filed:
Feb. 24, 1993
Hidekazu Takano, Kouriyama, JP;
Tokio Yoshimitsu, Kouriyama, JP;
Akinori Hibino, Kouriyama, JP;
Yoshihide Sawa, Yamatotakada, JP;
Motoyuki Toki, Kyoto, JP;
Yang Wu, Kyoto, JP;
Yuen C Tak, Kyoto, JP;
Tadao Ohnaka, Kyoto, JP;
Matsushita Electric Works, Ltd., Osaka, JP;
Abstract
An internal composite layer for a multilayer circuit board, which is composed of an electrically insulating substrate with a copper layer formed thereon and a film of a coupling agent covering the copper layer is fabricated in accordance with the following method. That is, the copper layer is treated with a base or the base and an accelerating agent to supply hydroxyl groups to a surface thereof. Subsequently, thus treated copper layer is coated with the coupling agent, e.g., a silane coupling agent. The coupling agent is chemically bonded to the treated copper layer by the reaction of the hydroxyl groups with the coupling agent, so that an adhesion strength between the copper layer and the coupling agent is remarkably increased. In addition, since it is not necessary for forming a copper oxide layer in the surface of the copper layer, the internal composite layer shows excellent acid resistance without causing a pink-ring which usually occur around a through-hole plating.