POLYOLEFIN RESIN COATED STEEL MATERIAL

摘要

PURPOSE:To obtain excellent high temp. cathode release properties, high temp. water resistance and evaporation heat cycle properties by setting the thickness of the first primer layer on a chromate treatment side among two or more primer layers to a specific value range and setting the whole film thickness of the primer layers to a specific value range. CONSTITUTION:The surface of a steel material 1 to be coated is washed by a physical means such as shot blasting or a chemical means such as pickling and chromate treatment 2 is applied to the washed surface of the steel material as under treatment for enhancing adhesiveness and corrosion resistance. The first primer layer 3 among two or more primer layers is formed on the surface of the steel material subjected to chromate treatment so that the film thickness of a cured film becomes 0.1-3mum. After the first primer layer is formed, the second primer layer 4 is laminated and cured in the same way as the first primer layer 3 and the whole thickness of the primer layers is set to 10-50mum. A polyolefin resin coating layer 6 is provided to this steel material through a modified polyolefin adhesive resin layer 5.