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:
Apr. 24, 2012
Filed:
Mar. 22, 2005
Yutaka Yoneda, Tokyo, JP;
Hajime Iseri, Tokyo, JP;
Shintaro Mori, Tokyo, JP;
Kurita Water Industries Ltd., Tokyo, JP;
Abstract
The present invention provides a corrosion inhibition method which minimizes environmental adverse effects by using phosphate base anticorrosives without using zinc salt base anticorrosives and by reducing the concentration of the phosphate base anticorrosives, enables stable formation of an effective initial protective film, and does not affect water treatment after the formation of the initial protective film. In an initial protective film formation process of forming an initial protective film on a surface of an iron-based metallic member of a water system by adding anticorrosives to the water system, at least one selected from a group consisting of pyrophosphoric acids and pyrophosphates is employed as the anticorrosives and the initial protective film formation process is conducted such that the initial pH at the start of the initial protective film formation process is adjusted to be 5 or more and less than 7 so that the pH at the end of the initial protective film formation process becomes 7 or more.