Non-yellowish and heat-resistant adhesive for a transparent heat sinking film

The development of optical communication techniques and optical components is rapidly progressing in the era of high-speed information communication. In this area, many studies have been carried out to investigate highly transparent optical adhesives. UV-curing adhesives, which rely on irradiating ultraviolet rays, are a major candidate for use in this field. However, they suffer from thermal degradation and discoloration due to long-term UV irradiation. Thus, in this study, we present a transparent adhesive by replacing the photo-initiator to improve the yellowish discoloration phenomenon, which affects aging and low surface quality. By replacing 2-benzyl-2-(dimethylamino)-4′-mopholinobutyrophenone, which causes yellow changes due to a red-shift and donation electron groups, with α -hydroxycyclohexylphenyl ketone, this approach was successful to improve the yellowish discoloration problem. By taking advantage of the excellent thermal and mechanical stabilities in addition to resistance to long-term UV irradiation, a transparent heat dissipation film formed by grid-patterned boron nitride nanosheets was manufactured by a transfer printing method. The film can be utilized as a major component in electrical and optical films which require thermal resistivity and optical transparency.