Study of Relationship Between Ink Trapping Rate and Color Difference

The ISO standard and Chinese national standard require to control the secondary color reappearance by chroma value, but the printing production in china are used to control the secondary color by trapping rate. Making use of the experimental methods, this paper analyzes quantitatively the relationship between trapping rate of the secondary color and color difference. It puts forward the fluctuating tolerance of the trapping rate in 4-colour process printing. The conclusions can be used to guide the printing process control according to the standard.