The influence of physico-chemical parameters of fountain solution on print quality

The influence of pH, conductivity and Ca ion concentrations of fountain solutions on the quality of tone, dot, line and text was investigated. Physico-chemical parameters of fountain solutions were analyzed by standard methods. Image quality assessment (IQA) was carried out using the ISO methodology and ImageJ software. The obtained data of the mechanical and optical tone value, dot circularity, line and text raggedness were compared and correlated with the physico-chemical parameters of fountain solutions. The results of tone and dot quality indicated the great influence of pH, conductivity and Ca 2+ ion concentrations of fountain solutions on the formation and circularity of magenta dots. The highest mechanical and optical tone value increases were observed in the mid tones of magenta color. The mutual nonlinear dependence, described by second-order polynomial, was existed between magenta dot circularity and the printed sheets. The results of line and text raggedness indicated that magenta lines and text and analyzed physico-chemical parameters of fountain solution were not in the mutual dependence.