SURFACE-CONDITIONING COMPOSITION, METHOD FOR PRODUCTION THEREOF, AND SURFACE CONDITIONING METHOD

摘要

Disclosed is a surface-conditioning composition which can form a denser phosphate coating film having a more satisfactory coating weight on the surface of a metal material compared to a conventional one and, therefore, can reduce the electrolytic corrosion of a metal material during a chemical conversion treatment, can form a chemical conversion coating film having a satisfactory coating weight even when applied to a hardly convertible metal material (e.g., an aluminum metal material, a high tensile strength steel plate), can improve the productivity rate of the chemical conversion treatment, resulting in the reduction of the time required for the chemical conversion treatment, and enables a metal phosphate particle to be dispersed in a surface-conditioning solution highly stably. A surface-conditioning composition which comprises a particle of a phosphate of a bivalent or trivalent metal and has a pH value ranging from 3 to 12. The particle has a D₅₀ value of 3 µm or less. The composition additionally comprises (1) a phenolic compound and (2) a stabilizing agent.