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. 21, 1991
Filed:
Apr. 11, 1989
Arend Schuurman, Drachten, NL;
U.S. Philips Corp., New York, NY (US);
Abstract
The invention relates to a method of manufacturing a shear plate for a dry-shaver, which shear plate is formed with perforations, at least one side of a metal sheet being provided with a layer of a photosensitive material, which photosensitive material is exposed to radiation via a mask formed with a pattern of holes corresponding to the pattern of the perforations, after which the photosensitive material is developed and the perforations are formed in the metal sheet by etching. In accordance with the method a positive photosensitive material is used and in at least two stages at least two masks are employed, the method as defined above being carried out using a first mask and, subsequently, in the second stage using a second mask that part of the positive photosensitive material which was covered by the first mask being exposed to radiation, upon which said material is developed and the etching process is continued.