Ultraviolet-curable Material with High Fluorine Content for Biomimetic Functional Structures Achieved by Nanoimprint Lithography with Gas-permeable Template for Life Science and Electronic Applications

Abstract

Fluorine materials exhibit excellent properties, such as high water repellency, low adhesion, and chemical resistance, owing to their low surface energy. They also exhibit high thermal and oxidation stability owing to the strength of the C-F bonds. Recently, in the field of life science, further improvement of the low adherence and antifouling properties of biological substances and microorganisms by imparting surface properties to fluorine materials through pattern fabrication technology has attracted considerable attention. However, fluorine materials exhibit high thermal expansion and contraction, making it difficult to apply fabrication methods, such as injection molding and hot embossing. Conventional focused ion beam and laser processing are difficult for further pattern fabrication. Here, an ultraviolet (UV)-curable material with a high fluorine content (44wt%) was created, and the pattern fabrication of 80-nm line structures was performed on the material by UV nanoimprint lithography using the gas-permeable template that can permeate the gas entrained during pressurization. The water contact angle was 127.3°, with 129.7° being the most favorable, achieved by a combination of the water-repellency characteristics of the UV-curable material with high fluorine content and fine line patterning in the nanometer range. We discovered the possibility of creating surface functions on short-chain perfluoroalkyl sulfonate (PFAS) substitutes with a relatively low impact on the environment and human body by establishing a pattern fabrication method for long-chain PFAS, which is more difficult to pattern fabricate, as a preliminary experiment.