A study on UV-curable adhesives for optical pick-up: I. Photo-initiator effects

Ultraviolet curable optical pick-up adhesive composites composed of acrylic and methacrylic mono-, bi- and trifunctional monomers and two kinds of urethaneacrylate oligomers has been easily prepared by dual planetary mixer. And various fillers, thixotropic agents, antiemission and rheological additives were also used. The free radical photo-initiated polymerization reaction followed with various photo-initiators and its physical and mechanical properties were tested within 30 s of UV-irradiation. In this paper, we studied the influence of the photo-initiators and their mixtures on the polymerization rate of the adhesive compositions were studied. From these results, the mixture Irgacure 184 and Irgacure 819 provides synergic effects of surface and through curing. UV-adhesives of two types were well applied and settled in CD and DVD optical pick-up body at the reliability evaluation of Samsung Electronics' production lines.