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:
Jan. 08, 1991
Filed:
Apr. 10, 1989
Katsue Masui, Hyogo, JP;
Isao Kobayashi, Kanagawa, JP;
Shigeru Kubota, Hyogo, JP;
Toshimoto Moriwaki, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In a process for fabricating a printed circuit board, a positive resist layer is electrodeposited on a copper clad laminate to ensure that the walls of through-holes in the substrate are completely coated with the resist, or alternatively, a film having a positive resist layer coated thereon is thermocompressed onto the copper clad laminate with the film being in contract with the latter, so as to cover both top and bottom of each through-hole. By subsequent treatments including resist exposure, development, copper foil etching and resist stripping, a high-density wiring pattern can be formed on the substrate in a uniform and consistent way even if through-holes exist in the substrate.