| 摘要 |
PROBLEM TO BE SOLVED: To obtain a flatting agent for a coating material, which has a good workability and a high flatting effect and can give a difficultly stainable coating film by selecting a flatting agent comprising an aggregate (a flatting filler) having an at least specified oil absorption value and a specified particle diameter and hydrophobic silica. SOLUTION: This flatting agent comprises an aggregate (A) having an oil absorption of below 80ml/100g and a size of below 100μm and hydrophobic silica (B). A coating material containing this agent has a good workability and can give a difficultly stainable coating film having a high flatting effect. Examples of A used include inorganic fillers and organic resin beads. Mica is particularly desirable in respect of its ability to retain flowability. B is desirably silica surface-treated with dimethylpolysiloxane. The mixing ratio A/B is 5:1 to 3:1 by weight. It is desirable that the agent further contains 5-60wt.%, based on A, crosslinked resin (e.g. acrylic resin), because the obtained coating material can resist the formation of streaks of rainwater flow.
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