Anodic electrophoretic coating method

US6350358B1 · kind B1 · utility

Assignee

• E.I. DU PONT DE NEMOURS AND COMPANY · US

Inventors

• Eduard Ehmann · Sprockhövel, DE
• Manfred Evers · Velbert, DE
• Armin Gobel · Syke, DE
• Bettina Vogt-Birnbrich · Solingen, DE
• Konstadinos Markou

Key dates

• Filing date: Aug 21, 2000
• Grant date: Feb 26, 2002
• Expiry date: Aug 21, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D13/24
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A method for anodic electro-dip lacquer coating, wherein coating medium which is consumed in an anodic electro-dip bath is compensated for by an under-neutralised anodic replenishment material, wherein the replenishment material comprisesA) a pigment-free aqueous binder vehicle component with a solids content of 40 to 70% by weight, an MEQ value of 15 to 40 and a content of organic solvent of ≦0.5% by weight, andB) a pigment-containing aqueous paste resin component with a solids content of 60 to 75% by weight, an MEQ value of 5 to 15 and a content of organic solvent of ≦1.0 % by weight,wherein A) and B) are present in a ratio by weight of 1:1 to 4:1 and the mixture of A) and B) has a solids content of 45 to 73% by weight, a solvent content of ≦0.75% by weight and an MEQ value which is 50 to 70% lower than the MEQ value of the electro-dip bath.