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. 30, 2020
Filed:
Jul. 30, 2014
Kansai Paint Co., Ltd., Hyogo, JP;
Yukihiro Nemoto, Kanagawa, JP;
KANSAI PAINT CO., LTD., Hyogo, JP;
Abstract
An object of the present invention is to provide a method for forming a multilayer coating film, the method capable of achieving excellent finished appearance and excellent corrosion resistance without affecting electrodeposition coatability even when a part or all of the water-washing step is omitted after chemical conversion treatment, and to provide a coated article. The invention provides a method for forming a multilayer coating film, comprising forming a chemical conversion coating film and an electrodeposition coating film on a metal substrate by Step 1 of immersing a metal substrate in a chemical conversion treatment solution to form a chemical conversion coating film, and Step 2 of omitting a part or all of the water-washing step, and performing electrodeposition coating on the metal substrate using a cationic electrodeposition coating composition to form an electrodeposition coating film, wherein the chemical conversion treatment solution contains less than 500 ppm of sodium ions on a mass basis, and hexafluorozirconic acid. The chemical conversion treatment solution preferably contains no less than 5 ppm to less than 50 ppm of sodium ions, no less than 5 ppm to less than 90 ppm of calcium ions, less than 100 ppm of potassium ions, and less than 90 ppm of magnesium ions, on a mass basis; and is used continuously.