Analysis And Control Of Color Qualty Of Printed Products Based On Digital Printing System

Printing is a mass reproduction of faithful original.Therefore,it is always the unremitting pursuit of the industry to seek space and ways to improve the quality of printing.The analysis and control of printing quality has always been the core of our work.The quality of printing color is influenced by many factors.Studying the quantitative influence relationship of single factor is the foundation of printing quality control.Based on the laboratory's digital printing technology equipment,through the theoretical analysis and experimental investigation of color quality,this paper explores the controllability of the printing quality of the digital printing system from three aspects of the printing color sequence,screening method and color controllability of digital system.The specific work and research results of this paper are as follows:(1)With special screening method and color sequence change strategy,a printing test plate is designed for the digital printing system and test equipment in the laboratory.Printing experiment,sample sheet extraction,data measurement and data preprocessing are carried out in turn.The analysis of the color rendering difference between the densitometry system and the colorimetric system shows that the printing of different color rendering effects will be produced by printing with different color order,and the setting of additive and proportionality of density is challenged again;(2)Aiming at the digital system,based on the analysis of the source and impact of quantization errors,an experimental test version was designed and printing experiments were carried out.Under the premise of excluding the influence of quantification error and the calculation error of Demichel equation,the density difference analysis and color difference calculation between the theoretical color rendering effect and the experimental data are carried out for the average color rendering data of single and double color ladders.And the ladder data of different positions,and the quality controllability of digital system is studied and analyzed.Research shows that in addition to quantization errors,digital systems also have problems with positional color differences and dot expansion.(3)The screening error is analyzed by comparing the color difference between different screening methods.Using the CIE1976LAB color difference formula,through the color comparison between the experimental measurement value under a specific screening method and the theoretical calculation value(calculated based on the color element chromaticity and the color element area rate),a system that considers the influence of the screening and the influence of the quantization error is carried out.Discussion on the controllability of printing quality.