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, 2001
Filed:
Jan. 19, 1999
Nippon Paint Co., Ltd., Osaka, JP;
Abstract
A method is provided for forming a film having excellent anticorrosion properties on a metal surface without producing sludge, and without using phosphorus or chromium. In this method, the following steps (a)-(c) are performed on a metal material: (a) degreasing, (b-1) pretreatment if necessary, and (c) which comprises the following steps (c-1) or (c-2). The film-forming step (c-1) is a step for forming a film by bringing the metal material in contact with an aqueous solution comprising at least one of the following compositions (A), (B), (C) or (D): (A) is a monomer comprising a sulfonium group at one end of the molecule. (B) is a water-soluble polymer obtained by homopolymerization or copolymerization of the monomer (A). (C) is an emulsion or water-soluble polymer comprising a sulfonium group obtained by copolymerization of the monomer (A) and a radical-polymerizable unsaturated monomer excluding the monomer (A). (D) is a composite emulsion comprising a sulfonium group wherein inorganic particle core are coated by a layer comprising a copolymer of the aforesaid monomer (A) and a radical-polymerizable unsaturated monomer excluding the monomer (A). The film-forming step (c-2) is a step for forming a film by electrodeposition wherein the metal material is dipped in an aqueous solution comprising at least one of the above compositions (A), (B), (C), (D), and a current is passed between a cathode and an anode with the metal material as cathode.