Patent ID: 7060758

Claim:
A powder coating material which comprises a main material including a polyester polyol having a fraction of hydroxyl group bonded to secondary carbon atom of 30% or greater based on an amount of an entire hydroxyl group, and a curing agent comprising a polyisocyanate polyaddition composition which is obtained by reacting (A) a polyisocyanate compound obtained by converting a bis(isocyanatomethyl)cyclohexane into a uretidione compound, the polyisocyanate compound having a content of a latent NCO group [(a content of free NCO group after a heat treatment at 180° C. for 1 hour)−(a content of free NCO group before the heat treatment)] of 16 to 30% by weight and an isocyanurate fraction [a content of an isocyanurate skeleton structure×100/(a content of an isocyanurate skeleton structure+a content of a uretidione structure)] smaller than 5% by weight, and (B) a compound having active hydrogen atom which comprises a combination of (a) a compound having at least two active hydrogen atoms in one molecule and (b) a compound having one active hydrogen atom in one molecule in amounts such that a ratio of an amount by equivalent of active hydrogen atom in component (a) to an amount by equivalent of active hydrogen atom in component (b) is in a range of 1 to 99, wherein the reaction of component (A) and (B) is conducted in a manner such that a ratio of an amount by equivalent of active hydrogen atom in component (B) to an amount by equivalent of isocyanate group in component (A) (a ratio of amounts by equivalent of active hydrogen atom/isocyanate group) is in a range of 1.0 to 2.0.