Photochemical adhesion of fused silica glass for UV transmittance

摘要

The new, strong adhesion method has been developed for optical materials to transmit vacuum ultraviolet rays by using silicone oil. Silicone oil (dimethyl siloxane) has the main chain of siloxane bonds like quartz and the side chains of methyl group. By irradiating ultraviolet rays in oxygen atmosphere, the organic silicone oil was photo-oxidized and changed into inorganic glass. The silicone oil was poured into the thin gap between two pieces of silica glass in oxygen atmosphere and irradiated with the Xe_2 excimer lamp. Consequently, the siloxane of the silicone oil was bonded with the O atoms that had been absorbed on the glass surface to form SiO_2. The UV transmittance of the silicone oil was improved by 62%, from 30% before the lamp irradiation to 92% after the 60-minute irradiation. Furthermore, the adhesive strength of the silicone oil was enhanced from 0 kgf/cm~2 before the irradiation to 180 kgf/cm~2 after the irradiation. The honeycomb structure board and plane mirrors were adhered with the Xe_2 excimer lamplight and photo-oxidized silicone oil.