| 摘要 |
PURPOSE:To provide a paint resin compsn. which has excellent resistance to chipping and gives paints suitable for use in the intercoating of the outer plate of an automobile body, by blending a high-molecular linear polyester with a branched polyester having a relatively low MW in a specified weight ratio. CONSTITUTION:At least one linear polyester (A) having a number-average MW of 4,000-30,000 and at least one branched polyester (B) having a number- average MW of 800-4,000 are prepd. In the diagram representing the relationship between the mixing ratio R (wt%; A/A+BX100) of component A and the number-average MW of component A, components A and B are mixed in such a proportion that the mixing ratio R is within the range surrounded by 3 points of (number-average MW, R) = (4,000, 15%), (4,000, 90%) and (3,000, 15%), thus obtaining the desired paint resin compsn. An amino-aldehyde resin as a hardener is added to the compsn. to obtain paint having good resistance to chipping. |
