Patent ID: 7235591

Claim:
An ultraviolet-curable coating composition comprising: (A) an ultraviolet curable four or more functional groups-containing polyfunctional (meth)acrylate comprising four or more (meth)acryloyl groups in the molecule and a number average molecular weight of 300 to 2,000, (B) a lactone-modified polymer of polyhydric alcohol mono(meth)acrylate comprising 25 to 60 percent by weight of ε-caprolactone ring-opening addition product and having a hydroxyl value derived from the lactone modification of 100 to 180 mgKOH/g, and/or a lactone-modified polyester resin comprising 10 to 50 percent by weight of lactone ring-opening addition product and having a hydroxyl value of 50 to 180 mgKOH/g, (C) a non-yellowing polyisocyanate compound and/or an amino resin, (D) a light stabilizer, and (E) a photopolymerization initiator, wherein the weight ratio of component (A) to the total weight of components (B) and (C) is 10:90 to 50:50, the weight ratio of component (B) to component (C) is 90:10 to 20:80, and the components described above are formulated to obtain a cured paint film having a Knoop hardness of 10 to 18 and a molecular weight of intercrosslinking of crosslinked resin component in the cured paint film of 150 to 300.