| 摘要 |
[The Problem] To provide coating compositions wherefrom coated films may be obtained with excellent coating operation properties and excellent acid and rain resistance, stain resistance, moisture resistance, weather resistance and abrasion resistance. [The Means of Solution] Resin compositions for coatings and coating compositions containing these, which are: (A) copolymers containing units based on radical-polymerizable monomers having epoxy groups, and groups derived from dimethylolalkanoic acids are bonded by the reaction of some of the epoxy groups with the carboxyl groups of dimethylolalkanoic acids, which are copolymers wherein the epoxy values are 100 to 250 mgKOH/g; the hydroxyl values are 5 to 15 0 mgKOH/g; and the weight average molecular weights are 2,500 to 15,000; (B) resins having carboxyl groups, with acid values of 100 to 340 mgKOH/g, hydroxyl values of 100 mgKOH/g or less and weight average molecular weights of 700 to 10,000 and (C) crosslinking agents to react with the hydroxyl groups and the proportion of component (A) and component (B) is a proportion of the epoxy value of (A) to the acid value of component (B) of 0.9 to 1.1 and the proportion of component (C) that is contained is 1 to 15% by mass of the total resin solid fraction.
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