摘要 |
PROBLEM TO BE SOLVED: To provide an organic coated heavy corrosion-proof steel material capable of suppressing progression of cathode peeling over a long period by introducing an adhesion mechanism which is different from an expression mechanism of adhesive force of a conventional steel material/coating layer mainly composed of acid-base bond.SOLUTION: In a corrosion-proof steel material including a chemical conversion treatment layer and an organic corrosion-proof layer on the surface thereof, the chemical conversion treatment layer is formed by such a way that the steel material surface is coated with water and a process liquid containing alkoxysilane having a straight-chain alkyl group, washed by water, and then subjected to a chemical conversion treatment for heating at 50-200°C.SELECTED DRAWING: Figure 1 |