RUST-PROOFING OF STEEL

摘要

PURPOSE:To form a uniform and dense rust-proofing film free from water- permeability and gas-permeability on a surface of a steel material, by using a rust-proofing agent composed mainly of a phenoxy resin and a blocked isocyanate compound. CONSTITUTION:A cleaned steel material is immersed in a solution of a rust- proofing agent composed mainly of 60-95wt.% phenoxy resin and 5-40% blocked isocyanate compound at a concentration of 5-15%. The coated steel material is immersed in a solution containing a rust-proofing agent at a concentration of 15-25%. The coated steel is dried preferably by applying gentle air flow of 1-3m/sec in the pulling up of the steel from the bath. The process enables the coating of a steel material with a coating film having high adhesivity, increased thickness and excellent corrosion-proofing property in excellent coating workability.