Evaluation on printing color appearance of glossy ink-jet paper

Ink-jet printing, one of the non-impact printing techniques, has replaced traditional printing methods in many printing industry fields. In general, the evaluation on printing color appearance of glossy ink-jet paper is accomplished by CIELAB color difference scale. The standard CIELAB color difference scale is suitable for large uniform color targets, but not on images. The aim of this study is to drive a well-performed color appearance model, which can simulate the sensitivity function of human vision system and measure the image on a pixel-by-pixel method so as to evaluate the printing color appearance of glossy ink-jet paper. The S-CIELAB model, which takes into account the spatial blurring of human eyes, is used to measure color differences between original images and ink-jet printing images. A pair-comparison psychophysical experiment was carried out to study the perception of printing color appearance. The calculated results by S-CIELAB model were consistent with psychophysical experiment. The S-CIELAB model was compared with the color difference obtained from spectrophotometer. It could be found that S-CIELAB was more appropriate for the printing color appearance evaluation. The influence of coating structure of glossy ink-jet paper on printing color appearance could also be characterized by this model. It has been proved that a microporous type of paper surface had better color appearance than a swellable type of paper surface on professional ink-jet printer.