Abstract: A method for measuring the color difference betweeen a sample dye and a standard dye by testing the color properties of both dyes, which comprises determining, in advance, the relation of the color difference of dyeings (between the standard dye and the dyes of the same family) to the color difference of dye solution (between a standard dye and the dyes of the same family) using the standard dye and two or more, preferably several, representative samples arbitrarily selected from plural lots of dyes, then calculating the color difference of dye solution between the standard dye and a sample dye, and predicting the color difference of dyeings from the calculated color difference of dye solution by referring to the relation obtained.

Abstract: A method for measuring the color difference between a sample dye and a standard dye by testing the color properties of both dyes, which comprises measuring the distribution curve of absorbance of individual components of the dye; determining the relationship between the color difference of dye solution and the color difference of dyeings with respect to the standard dye and representative samples arbitrarily selected plural lots of dyes; and predicting the color difference of dyeings from the color difference of solution between the standard dye and the sample dye.