| 摘要 |
PURPOSE:To stabilize product quality by mixing specific weight % of ultrafine particulate hydrophobic silica with metallic powder or carbonate to coat the surface thereof and mixing the raw material contg. prescribed % or above of the coated metallic powder or carbonate. CONSTITUTION:0.3-6wt.% Ultrafine particulate hydrophobic silica is preliminarily mixed with the metallic powder which has a deoxidation effect to coat the surface thereof. The metallic powder contg. at least >=50% the coated metallic powder is mixed with the other raw materials to manufacture the coating material. Further 1 or >=2 kinds of carbonates such as BaCO3 are subjected to the surface coating with 0.3-6wt.% ultrafine particulate hydrophobic silica by which the coating material is obtd. with the same treatmetn as in the case of the metallic powder. The metallic powder or carbonate of the coating raw material is coated with the ultrafine particulate hydrophobic silica, the reactivity with water glass is suppressed. The deterioration of paintability is thus prevented and the product quality is improved. |
