Disclosed is a coating method of intermediate-coating-less, which sufficiently keeps excellent appearance, weather resistance and corrosion resistance equal to a three layer coating in conventional technology. The method of the present invention comprises:
electrocoating an aqueous paint composition comprising at least two sort of resins which are insoluble with each other, a curing agent and a pigment, on an electrically conductive substrate,
heating it to form a layer separation, and then
curing to form a plural layered cured coating having at least two layers,
wherein a concentration of the pigment is distributed such that a pigment concentration (a) in the resin layer directly contacting air is relatively higher than a pigment concentration (b) in the resin layer directly contacting said electrically conductive substrate.
本发明公开了一种无中间涂层的涂层方法,该方法可充分保持与传统技术中三层涂层相同的优异外观、耐候性和耐腐蚀性。本发明的方法包括:
在导电基材上电涂一种
水性涂料组合物,该组合物至少包括两种互不相溶的
树脂、一种固化剂和一种
颜料、
加热以形成分层,然后
固化形成至少有两层的多层固化涂层、
其中
颜料的浓度分布为:直接接触空气的
树脂层中的
颜料浓度(a)相对高于直接接触所述导电基底的
树脂层中的
颜料浓度(b)。