An object of the present invention is to find a primer coating composition for aluminum wheels, the composition having excellent stability and being capable of forming a coating film having excellent corrosion resistance, edge corrosion resistance, and filiform corrosion resistance. The invention provides (1) a primer coating composition for aluminum wheels comprising a copolymer resin (A), and 1 to 30 parts by mass of fumed silica (B) and 0.1 to 10 parts by mass of a magnesium-containing phosphoric acid-based compound (C), per 100 parts by mass of the total solids content of the copolymer resin (A). The invention also provides (2) the primer coating composition for aluminum wheels according to Item (1), further comprising 0.1 to 10 parts by mass of metal-ion exchanged silica (D), per 100 parts by mass of the total solids content of the copolymer resin (A).
本发明的目的是找到一种用于铝制车轮的底漆涂料组合物,该组合物具有优异的稳定性,并能形成具有优异的耐腐蚀性、耐边缘腐蚀性和耐丝状腐蚀性的涂膜。本发明提供了(1)一种用于铝制车轮的底漆涂料组合物,该组合物包括共聚物
树脂(A),以及每 100 份共聚物
树脂(A)总固体含量中含有 1 至 30 份(质量份)气相
二氧化硅(B)和 0.1 至 10 份(质量份)含
镁磷酸基化合物(C)。本发明还提供了(2)根据第(1)项所述的用于铝制车轮的底漆涂料组合物,该组合物还包括每 100 份共聚物
树脂(A)的总固体含量中含 0.1 至 10 份
金属离子交换
二氧化硅(D)。