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:
Jun. 20, 2000
Filed:
Jun. 15, 1999
Hirotada Iida, Tokyo, JP;
Nobuhiro Yoneyama, Saitama, JP;
Seiju Tobishima, Chiba, JP;
Toshio Itahana, Tokyo, JP;
Kunihiko Kojima, Chiba, JP;
Toyo Gosei Kogyo Co., Ltd., Chiba, JP;
Abstract
An effective method for producing a 1,2-naphthoquinone-2-diazide or a sulfo-substituted compound thereof from a 2-diazo-1-naphthalenesulfonic acid or a sulfo-substituted compound thereof. A 1,2-naphthoquinone-2-diazide derivative or a sulfo-substituted compound thereof is derived from a 2-diazo-1-naphthalenesulfonic acid or a sulfo-substituted compound thereof by use of an aqueous alkaline solution containing iodine; an aqueous alkaline solution containing iodine which is dissolved in an organic solvent; or an aqueous alkaline solution containing an oxidizing agent and iodine or an iodine compound.