Identification and Causes of Puddling and Volcanoing in Publication Gravure Printing

For the past several years, the incidence of puddling and volcanoing in publication gravure printing has been increasing markedly. These print anomalies are characterized by small localized areas of excessively thick films of ink, which can fracture and erupt while drying mostly in high density areas of the print. In this paper it is shown that the causes are related to solvent entrapment. This can be a function of solvent evaporation rate, ink drying rate, paper absorptivity of solvents and ink/paper interactions. Laboratory methods for observing and identifying these conditions and some suggested remedies are presented.