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. 14, 1995
Filed:
Dec. 23, 1993
Kazumi Goto, Kanagawa, JP;
Hiroshi Sasaki, Kanagawa, JP;
Mitsubishi Pencil Kabushiki Kaisha, Tokyo, JP;
Tsukasa Felt Shoji Co., Ltd., Tokyo, JP;
Abstract
A process for producing a sponge rubber stamp having open cell of the present invention comprises the steps of superposing an unvulcanized rubber sheet (A) containing a water-easily soluble powder upon an unvulcanized rubber sheet (B) containing an acid-soluble powder, heating/pressing them to form an integral laminate, treating the integral laminate with water to make the layer (A) porous, sculpturing the surface of the layer (B) of the integral laminate by a laser beam to form a stamp surface thereon, and then treating the integral laminate with an aqueous acid solution. No microcracks occur in the stamp at the formation of the stamp surface, and the stamp surface precision and the durability of the obtained stamp are excellent. In addition, the formation of a prototype and a matrix of the stamp as well as the treatment of the stamp can be simplified.