| 摘要 |
PURPOSE:To provide the titled paint which given a coating film having excellent corrosion resistance and adhesion to metallic materials, consisting mainly of a specified aq. polyurethane resin having a specified corsslink density and optionally an extender pigment. CONSTITUTION:An aq. polyurethane resin (A) having a crosslink density of 0.02-1.00 per 1000 atomic weight (e.g., an anionic or cationic aq. polyurethane obtd. by reacting a polyhydroxy compd. having at least two active hydrogen atoms and an average MW of 50-100,000 or a mixture thereof with a polyamine compd. having at least two active hydrogen atoms and an average MW of 50-100,000 with an org. polyisocyanate and a compd. having a salt-forming group and active hydrogen atoms capable of reacting with NCO groups and emulsifying the resulting polyurethane resin having a salt-forming group in water in the presence of a salt forming agent) is blended with an extender pigment (B) having a pH of not higher than 6 (e.g., CaCO3) in an amount of not more than four times by weight that (on a solid basis) of the component A. If desired, a dispersant, an anti-skinning agent, an anti-foaming agent, etc., are added thereto.
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