Build Of Ink Presetting Model Based On Web Offset Printing

The digital workflow develops quickly with the digital technology osmosis to printing industry. Application of the digital workflow and CIP3/CIP4technology to reduce the operation time, decrease the waste of materials and improve production efficiency has become the symbol of printing enterprises competitiveness. In the printing job preparation process, enhance ink key preset precision and reduce the time of adjusting ink key is becoming the research hot spot, it is necessary to break through this bottleneck.In this paper, for the technical problems of domestic commercial rotary printing machine ink preset, using the printing standardization and ink preset model, focused on solving the commercial rotary printing machine dot gain and printing compensation method. Calculating ink zone image coverage by PPF document, then construct the relationship between ink key opening value and image coverage. Using of MATLAB programming software to establishing the ink preset curve and ink preset model include its software.The results of the printing standardization show that after dot compensation, rotary positive and negative dot gain in a standard range. Especially the50%dot gain of C/M/Y reduced from25%to15%, and the four-color dot gain curve become more smoothly.The results of ink preset show that the original image coverage is very accuracy; error is less than1.5%. It is linear output by ignoring the different of rotary ink zone width and the original image width. And C/M/Y has the same image coverage output curves. On the experiment of ink key opening, Y has a big difference with other colors, since that Y ink have different transfer properties and adhesion properties from those of other colors.During development on ink preset system model processing, according to the results of corresponding algorithm. Fitting out of the ink preset curve through the relationship between dot area percentage and the ink opening value. By using MATLAB programming software, design the function of loading and visual with image coverage and the ink key opening value. Developed a software that can calculate the ink key opening value through corresponding image coverage.