Influence of the pad printing plate‘ printing element depth on the quality of the printed product

Abstract

One of the biggest challenges in mass printing is repeatability and stability of the ink transfer from the printing plate onto the printing substrate. The pad printing is characterised by indirect ink transfer from a gravure printing plate. Beside area of the printing elements, on the pad printing plate one should take into account their depth as it is a factor which directly influences the printing ink quantity, i.e. overall quality of the printed product. The photopolymer pad printing plate production includes two exposures with UV irradiation, first to make difference between printing and nonprinting areas and second to form partitions (walls) in the printing elements. The duration of the second exposure directly influences the final depth of the printing elements. The aim of this paper is to determine influence of the second exposure on the depth of the printing elements, consequently on the reproduction of the pad printing plate elements. For this purpose four pad printing plate samples with various coverage tone value fields will be made by variation of the second exposure duration. Results have shown that second exposure duration significantly influences the printing elements size and therefore should be defined precisely in order to form printing elements of desired depth.