AATCC Gray Scale for Staining

Gray Scale for Staining
This scale is used in colorfastness tests for evaluating staining on undyed textiles. The scale consists of pairs of nominally white and gray color chips each representing a difference in color or contrast (shade and strength) corresponding to a numerical grade for staining. The fastness grades of the scale steps and the corresponding color difference and tolerances are determined by the CIE L*a*b* (CIELAB) formula. Fastness grade 5 is represented on the scale by two identical white reference chips mounted side by side, having reflectance of not less than 85 percent. Fastness grades 4.5 to 1, inclusive, are represented by a reference white chip identical with those used for grade 5 paired with similar but neutral gray chips. Scale features 3 languages; English, Spanish, and Chinese.  Specific tolerances and instructions for use of the scale are given in AATCC Evaluation Procedure 2. Order No. 8360