What scale is color fastness to washing rated on?

Color fastness to washing is typically rated on a numerical scale. The most commonly used scale for assessing color fastness to washing is the AATCC (American Association of Textile Chemists and Colorists) Gray Scale for Color Change. This scale consists of a series of color chips ranging from 1 to 5, with specific intervals in between. Each rating on the scale corresponds to a different level of color change or colorfastness after washing.

The AATCC Gray Scale for Color Change typically includes the following ratings:

1. Excellent: No change or minimal change in color.

2. Very good: Slight change in color, barely noticeable.

3. Good: Noticeable but acceptable change in color.

4. Fair: Moderate change in color, may be considered unacceptable in some applications.

5. Poor: Severe change in color, considered unacceptable.

During color fastness testing, the tested sample is compared to the color chips on the gray scale, and the corresponding rating is assigned based on the level of color change observed after washing. This scale provides a standardized and consistent method for evaluating and communicating the colorfastness performance of textiles and dyed materials after washing.

It's important to note that different testing methods and standards may use slightly different rating scales or terminology. However, the AATCC Gray Scale for Color Change is widely recognized and commonly used in the textile industry for assessing color fastness to washing.