| abstract |
An epoxy-bearing acrylic resin for powder coating which is a copolymer prepared from a vinylic monomer mixture comprising 10 to 60 wt.% of an alkyl ester of (meth)acrylic acid, 10 to 60 wt.% of an epoxy-bearing vinylic monomer and the balance consisting of other vinylic monomer(s) and having a weight-average molecular weight of 3000 to 20000, characterized in that the mean particle diameter is 80 to 800 νm, that the content of particles satisfying the relationship of 1 « R/r « 1.2 is 95 wt.% or above, that of particles wherein R is less than 62 νm is 5 wt.% or below, and that of particles wherein r exceeds 1000 νm is 5 wt.% or below, where r is the minor axis of each particle and R is the major axis thereof, and that the volatiles content is 1000 ppm or below. This acrylic resin is free from the problems of scattering of fine powder and smelling and therefore does not worsen the atmosphere in preparing coating materials, thus being excellent in workability. Further, it can give coating films free from pinholing and excellent in film performances such as gloss and smoothness. |