Original scientific paper
Customization of flexographic printing plates related to uvc-induced changes in the crosslinking degree
Tamara Tomašegović
; Faculty of Graphic Arts, Zagreb, Croatia
Sanja Mahović Poljaček
; Faculty of Graphic Arts, Zagreb, Croatia
Mirela Leskovac
; University of Zagreb Faculty of Chemical Engineering and Technology, Croatia
Abstract
In this paper, the swelling properties of photopolymer flexographic printing plates related to the variations of UVC post-treatment have been analysed. The aim of the research was to interconnect the changes in the cross-linking degree of the photopolymer material occurring due to the modified UVC radiation of the printing plate and the changes of its surface free energy crucial in the graphic reproduction process. Changes in the crosslink-ing degree in the photopolymer materials have been analysed by the swelling experiments. Results have proven that the partial dissolution of the photopolymer material caused by the immersion of the printing plates in vari-ous solvents is in the direct relation with the changes of the dispersive surface free energy. UVC post-treatment, used for the crosslinking termination and the definition of the surface properties of printing plates, is therefore directly affecting the resistivity of the printing plate in the solvent environment. By calculating the correlation coefficients for the weight loss of the photopolymer material in solvents and the dispersive surface free energy, the relation between the crosslinking degree and the UVC post-treatment has been established.
Keywords
photopolymer; flexography; UVC post-treatment; swelling; crosslinking; surface free energy
Hrčak ID:
174570
URI
Publication date:
19.12.2016.
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