Functionalized Cyclohexyl methacrylate based Copolymers for Negative Resist

Abstract

Three series of cyclohexyl methacrylate based copolymers having photo-reactive side chains (C=C double bond) were synthesized and examined their performances as photopolymer in the presence of suitable oxime ester or triazine type radical photo-initiators for 365 nm light. As a result, those polymers gave negative patterns with micrometer resolution. Correlation between photochemical reactivity and chain length of the side chain/density of reactive side chain in the cyclohexyl methacrylate main chain was observed. Sterically stacked nonpolar cyclohexyl groups may push out the polar reactive side chain, and length and density of the side chain controls cross linking between two reactive sites in the single main chain or two different main chains. The image on a printing plate has enough strength for practical times of run off the print. These polymers were white or transparent powder having enough stability to preserve. Over all, three copolymers have promising features as photopolymer for printing.