GB/T 250 Grey Scale for evaluating Change in color
Product Information :
GB/T 250 Grey Scale for assessing Change in color.
Compare the origin specimen and finished specimen with the grey scale visually to rating. When the color differences is equivalent to the level of grey scale, the colorfastness of specimen is equal to the level of the grey scale.
standards: GB, ISO, AATCC, DIN, BS, JIS, EN standards.
Precautions for use:
1. Keep the gray card clean.
2. Always check the gray card for fingerprints.
3. If the imprint has been found to interfere with the rating, the gray card must be replaced.
4. Try to avoid mechanical damage caused by touch.
5. If mechanical damage interferes with the rating, it should be replaced.
6. After the gray card is used up, put it into the sleeve.
