Paint pretreatment agent for coating-type paint, and coating-type painting method

Abstract

The pretreatment agent for use before forming a coat by paint application of the present invention contains (A) one or more metal elements selected from a group consisting of zirconium, titanium and hafnium, (B) fluorine, (C) one or more coupling agents selected from an amino group-containing silane coupling agent, its hydrolyzate, and its polymer, and (D) a component of at least one of an allylamine and a polyallylamine, in which the ratio by mass of the coupling agent (C) to the component (D), (C/D) is 1 or more. The coating method by paint application of the present invention includes a chemical conversion treatment step of chemically treating a metal substrate with the pretreatment agent, and a step of forming a coat by paint application on the chemically-treated metal substrate. When a coating film is formed through forming a coat by paint application on the surface of a metal substrate that has been pretreated according to the present invention, the coating film can have excellent adhesion, salt water resistance and impact resistance.

Dependencies are inferred from the claim text.