Formulation of blends of precolored nylon fiber

Two‐constant Kubelka‐Munk formalism was used to describe the color of blends of precolored nylon fibers. Pseudo‐Kubelka‐Munk absorption constants K and pseudo‐Kubelka‐Munk scattering constants S were calculated using masstone samples and blends of colored fiber with white. A masstone means 100% colored fiber in which no white or black is mixed. Various mixtures with white were tried and no systematic dependence of the calculated optical parameters on composition was discernable. With some colors, notably yellow and orange, mixtures with black were required for the calibration. Accurate color matches were obtained using the two‐constant formalism especially when the proposed match contained the same primary fibers as did the standard. For matches in which the primary fibers used in the sample differed from those in the standard, the closeness of the visual match depended on how closely the primary colors in the sample resembled those in the standard. Since the eye can discern individual colors in a fiber blend, it was possible to have a visual mismatch despite colorimetric equivalence. With a large enough group of primary colors, it was generally possible to find one or more alternative formulations which matched the standard. Sample‐preparation and measurement errors were found to be critical for determining color‐matching accuracy. All of the color‐matching error could be accounted for in terms of the sample‐preparation and measurement errors alone. This suggests that the sampling error was, in fact, a limiting factor in determining color‐matching accuracy.