Study on Relationship of Ink Thickness and Color Saturation

Abstract

In the offset printing process, the amount of ink supplying of fountain directly affects plate ink thickness, thereby affecting the color quality on the printed sheet. Ink layer thickness is difficult to judge by human eye, but we can regulate the ink thickness by detecting the color saturation. This paper describes using complex spectrum spectrometer measured data ink layer thickness and color saturation, draw two graphs of complex spectrum saturation and CIE saturation. Due to the different definitions of saturation, Cause their sensitivity of layer thickness changes response different. Two sets of data shows that the complex spectrum saturation contrast ΔS1 significantly higher than CIE saturation contrast. The data also showed that the ink color performance in terms of the relationship between layer thickness and saturation has an inflection point, the inflection point in the ink film thickness about 4μm, after reaching inflection point, even if the ink layer thickness continues to increase, there will be no significant changes in the saturation.