Pre-coated metal용 UV경화형 수지의 조성과 온도에 따른 물성

Abstract

To expand their applications, UV-curable coatings for pre-coated metal (PCM) require high flexibility and stiffness for formability and hardness, respectively. However, it is difficult to satisfy both properties of coatings. Therefore, this study was focused on each factor which affects the properties of UV-cured coatings or PCM. The curing conversion of UV-cured coatings was improved in oxygen-free atmosphere. The optimum UV irradiation for curing was 1500 mJ/cm2. Both mechanical and thermal properties were dependent on the degree of crosslinking. Tensile strength was increased and elongation was decreased, according to the degree of crosslinking. This results in hardness was increased and formability was reduced. UTM and erichsen cupping test were performed at different temperatures to improve poor formability. As the temperature raise, the tensile strength was decreased, but elongation was widely enhanced. The results showed that the formability was much improved at an elevated temperature due to the increased flexibility.