Paper-Ink Interaction in Non Impact Printing

In conventional printing technology the ink transfer is characterized by the effects of roughness and absorption, and by film split. Such phenomena as wetting, spreading, and capillary sorption are well recognized mechanisms of the paper ink interaction. These mechanisms are also important in non impact printing although in not the same way as in impact printing. The effects are strongly related to quality. The relations of the various mechanisms in electrophotography, thermography, and ink jet printing are analyzed in this paper. The experimental results indicate that the effects of roughness dominate the formation of print quality in these processes. The surface energetic relations and absorption behavior of the paper are also important. The evaluation of compatibility should also include determination of the polarity of the components. Absorption affects the fastness of the dots and controls the final dot size in ink jet printing. The paper summarizes some of the latest results obtained in the laboratory tests and non-impact printing trials concerning the basic mechanisms and final quality of the prints.