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:
Oct. 23, 2001
Filed:
Feb. 23, 2000
Tsuneyuki Ide, Yamaguchi, JP;
Hironao Okayama, Yamaguchi, JP;
Hiroaki Ikenaga, Yamaguchi, JP;
Susumu Shigemasa, Yamaguchi, JP;
Yasuo Tahara, Yamaguchi, JP;
Taizo Sato, Yamaguchi, JP;
Akira Ikeda, Yamaguchi, JP;
Toyo Kohan Co., Ltd., Tokyo, JP;
Abstract
An invar alloy steel sheet for shadow masks is provided which has improved etchability, an economical production method, a shadow mask made of the invar alloy steel sheet, and a color picture tube which incorporates the shadow mask. The invar alloy steel sheet is produced by hot working an alloy slab consisting of 33 top 40 wt % nickel with the balance being iron, and then subjecting the slab to a primary cold rolling at a rolling reduction ratio of not more than 80%, annealing at a temperature of at least 550° C., and subjecting the slab to a secondary cold rolling at a rolling reduction ratio of not more than 50%. The invar alloy steel sheet has a percentage of {100} texture of 60 to 80%.