Details:
Summary:
Sheetfed offset lithography is the most widely used printing process by Taiwan's printing industry, but there are no industry-wide specifications for press control to assure consistent quality across printing plants. As printing becomes more of a commodity and less of an art, it is necessary to develop a print quality specification standard for Taiwan. The main purposes of the study were to construct the attribute profile for the high-quality sheetfed offset lithography industry of Taiwan, and to establish the print quality specifications based on the attribute profile.
More than fifty company members of the Printing Industry of Taiwan (PIT) were invited to participate in the study. Thirty-three companies, representing the north, central and the south of Taiwan submitted a total of 95 sets of printed samples for this study; 45 sets were printed on coated paper and 40 sets on uncoated paper.
Participants were provided with an original test form created specifically for this research on a CD-ROM in digital format or a set of conventional litho film to produce 100 sheets print according to their in-house density aim points. All submitted samples were then measured with spectrodensitometers on solid ink density, dot gain, print contrast, trapping, highlight dots, shadow dots, hue error, grayness, gray balance, L*a*b* values, etc. The print quality specifications of the sheetfed offset lithography were derived from the analysis of those measurements. Various subgroups of the specifications are also discussed in the paper.