Industrial Tolerances, Performances of a Colour-difference Formula

Since 1976 J & P Coats (UK) Limited have employed an instrumental match prediction and pass/fail system in the Dyehouse in Paisley. The system was developed by the Research Laboratory of J & P Coats Limited and, since 1976, a number of modifications to the pass/fail formula has been made on the basis of bulk experience. These modifications culminated in the J & P Coats 1979 Colour-difference Formula. Since the introduction of the JPC 79 formula many thousands of pass/fail decisions have been made and the agreement between visual observer and instrumental decision has been good