abstract |
(A) a polycarbonatediol, (B) a trifunctional alcohol, and (C) a diisocyanate are subjected to reaction in the presence of (D) a (meth)acrylate compound represented by the general formula CH 2 ═CRCO(OC n H 2n ) p R′ or CH 2 ═CRCO(OC m H 2m ) q OCOCH═CH 2 , and (E) a di(meth)acrylate compound of alkylene glycol whose alkylene group is substituted as a lower alkyl group, and then (F) a hydroxyl group-containing (meth)acrylate is added to the resulting solution of urethane oligomers in (meth)acrylate to conduct terminal (meth)acrylating reaction of the urethane oligomers, thereby producing a UV-curable liquid polyurethane resin having a viscosity (25° C.) of preferably 150,000-1,000,000 mPa·s, where before or after the terminal (meth)acrylating reaction of the urethane oligomers (G) a photopolymerization initiator and (H) a hindered phenol-based antioxidant having a molecular weight of 500-2,000 are added thereto to form the UV-curable liquid polyurethane resin. The UV-curable liquid polyurethane resin can produce HDD gaskets, etc. in a cross-sectional shape with a good sealability by an automatic coating robot efficiently. |