Research on Blackness Classification of Polyester Knitted Printed Black Cloth

This paper analyzes and simplifies the commonly used color index Lab, combines the reflectivity integration curve, and divides the fabric blackness into two categories according to the degree of color. The concepts of achromatic blackness and chromatic blackness are proposed to create a classification method. The achromatic blackness classification is considered to be a ≤ 1, b ≤ 1, and L ≤ 22 which is divided into 5 levels for evaluation, with 5 as the highest and 1 as the lowest. The chromatic blackness classification is evaluated by the method of integrating the reflectance curve of the test sample and the standard sample. The method of number of level–number of segment is divided into 6 levels, of which 6 is the highest, 1 is the lowest, and each level is divided into 3 segments, which are represented by I, II, and III, with I being the highest and III being the lowest. These two categories can more intuitively reflect the user’s blackness classification requirements for black fabrics.