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, 1987
Filed:
Aug. 27, 1985
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A method of perforating through pores by etching in the manufacture of a shadow mask. This perforating method comprises the steps of selectively covering both surfaces of a thin metal plate with etching resistant film except a predetermined pore region; performing an etching to form recesses on the opening region of one surface of the metal plate; covering the one surface of the metal plate with an etching resistance material; etching the opening region of the other surface of the metal plate until the bottom of the etching resistance material buried in the recesses of the one surface of the metal plate is exposed; exposing both surfaces of the metal plate including the through holes by removing the etching resistant film and the etching resistant material; and etching the exposed surfaces of the metal plate again by contacting the exposed surface with an etchant.