Determination of industrial colour tolerance limits, case studies in the textile industry

摘要

The approach and findings during the application of instrumental colour quality control in industry are described, where the best tolerance formulae and tolerance limits were determined by correlating visual and instrumental evaluations. A panel of previously tested observers evaluated a collection of samples taken from production and colour measurements are then compared to these assessments, according to different colour difference formulae. The formula and the limit giving the best agreement with visual evaluations were determined with two different methods. For a large variety of textile substrates, processes and market situations the CMC(2:1) formula was always the best or one of the bests, but the limits varied widely, according to the individual application. Additional shade sorting, based on the tolerance limit, was also applied in several companies. The ideal box size was also determined by comparing visual and instrumental evaluations. The application as logistical tools was established according to individual necessities.