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. 29, 2018
Filed:
Jun. 24, 2009
Yousuke Matsuyama, Tokyo, JP;
Reiki Akita, Tokyo, JP;
Takuya Hasaki, Tokyo, JP;
MITSUBISHI GAS CHEMICAL COMPANY, INC., Tokyo, JP;
Abstract
A process for the production of an entry sheet for drilling a printed wiring board material, which process comprises forming a multi-layered water-soluble resin composition layer on at least one surface of a metal foil, wherein an aqueous solution of a water-soluble resin composition is applied to the metal foil, dried and solidified to form one water-soluble resin composition layer, the application, drying and solidification of the aqueous solution of the water-soluble resin composition are repeated at least once to form at least one water-soluble resin composition layer on the above one water-soluble resin composition layer, the multi-layered water-soluble resin composition layer is composed of these water-soluble resin composition layers, the multi-layered water-soluble resin composition layer has a thickness of at least 50 μm and is almost free from air bubbles, and an entry sheet for drilling a printed wiring board material obtained by the above process.