Synthesis and Characterization of Optically Clear Pressure-Sensitive Adhesive

Abstract

We synthesized Optically Clear Adhesive (OCA) polymers by free radical polymerizations and cured them as an interlayer between two polyethylene terephthalate (PET) release films. Some fundamental characteristics of OCA polymers including glass-transition temperature (T_g), molecular weight, viscosity, probe tack and peel strength were investigated with the change of methyl methacrylate (MMA) and 2-hydroxyethyl acrylate (HEA) monomers. The optical characteristics of OCA films were also investigated on the change of ripening temperature, high-temperature aging and heat-moisture aging. The resistance change rates of ITO-coated films were measured with heat-moisture treatment for two weeks. The results suggested that the OCA films can effectively protect ITO films and the synthesized OCA polymer can be expected to be applied to touch panel devices.