| 摘要 |
PROBLEM TO BE SOLVED: To provide an aqueous binder composition for a metal surface treatment agent, which is chromate-free, excellent in coatability and liquid stability, and can form a surface-treated film excellent in corrosion resistance, adhesion, and conductivity.SOLUTION: An aqueous binder composition for a metal surface treatment agent, having a pH of 4.0 to 10.0, includes a reaction product (A) of an amino group-containing silane coupling agent (a) and an epoxy group-containing silane coupling agent (b), a specific alkoxysilane compound (B), a stabilizer (C) such as phosphoric acid and water. The reaction product (A) does not substantially contain a not-reacted epoxy group based on the component (b), and all of hydrolyzable groups based on the components (a) and (b) are substantially hydrolyzed into silanol groups. |
