Unveil self-plasticized polyvinyl alcohol derived customizable patterned photosensitive resin films

Abstract

Since the invention of movable type in ancient times, relief printing, often called flexographic printing, has been performed to mass-produce artifacts ranging from decorative graphics to printed media. Polyvinyl alcohol (PVA) substrates are soluble in water with low toxicity but have the disadvantages of poor elasticity and brittleness. Thus, this study aims to improve the resilience of water-developable photopolymer resin plates by modifying PVA with allyl polyoxyethylene ether (APEG) in solution polymerization. In order to better control polymerization, the reactivity ratios of both were investigated (rVAC = 0.32 and rAPEG = 0.12). Impressively, the lowest glass transition temperature (Tg) of the modified PVA (m-PVA) can reach −49.98 °C, which is significantly lower than that of PVA0599 (degree of polymerization = 500, degree of hydrolysis = 99 mol%) (Tg = 52.02 °C). Moreover, this resultant m-PVA exhibits superior elongation at break (443.23 ± 37.65 %) than PVA0599 (9.98 ± 3.95 %). It is found that photopolymer plates of m-PVA have maintained a 98 % elasticity recovery rate even after water washing. Due to the better elasticity of m-PVA, the clarity of the photopolymer plate is higher than that of traditional PVA. This water-soluble self-plasticized m-PVA is expected to be applied to the fine flexographic printing industry, such as electronic devices, components, and sensors.