Excimer laser-induced photochemical modification and adhesion improvement of a fluororesin surface

Abstract

Modification of a selective area of a fluororesin surface was accomplished by using ArF excimer laser radiation and a boron complex with oleophilic or hydrophilic functional groups. The chemical stability of fluororesin is attributed to the presence of C-F bonds. The F atoms were abstracted by B atoms selectively from the area irradiated with excimer laser radiation and were replaced with the desired functional groups. In this modification, B(CH₃)₃ and B(OH)₃ were used: a boron compound with methyl groups to generate an oleophilic surface, and one with hydroxyl groups to generate a hydrophilic surface. As a result, the resin surface exposed to ArF laser radiation becomes oleophilic or hydrophilic. Both samples were bonded to stainless steel plates with an epoxy bonding agent and the tensile shear strength was 1.2 x 10⁷ Pa in both cases.