Research on Ink's Dot Area Percentage's Prediction in Digital Printing Based on Spectrum Analyzing

Digital printing can print directly the information which will be printed on the package box by digital print machine and internet or computer, which removes the procession of color separation, makeup, plate-making in the traditional printing. The digital print can print any number package box at any time and at any place, which can realize the variable data printing, and which has a price advantage in the short version printing. Therefore, digital printing is a good method for personalized packaging printing.In digital printing, color control is important for print quality detection. In this paper the dot area percentage of cyan, magenta, yellow ink can be predicted by measuring the color’s spectral reflectance in order to control the ink’s amount in digital print and realize the color’s precise control of cyan, magenta, yellow. In the prediction model of three color ink’s dot percentage, the characteristic of spectral reflectance curves for the various color ink is analyzed, and each ink’s high reflectivity and low reflectivity which is high correlation with the dot percentage is chosen and is calculated by normalization method in order to get each ink’s dot area percentage’ prediction model. At last by measuring the paper’s spectral reflectance and the using normalization method, paper’s color can be described, and the effect of paper on monochrome color ink’s dot area percentage can be analyzed. The research has important significance for packing box’s digital printing’s color high-fidelity reproduction.