Discussion in 'Print Glossary' started by Color Printing Forum Admin, May 13, 2007.

  1. Color Printing Forum Admin

    Color Printing Forum Admin Administrator

    Jul 2006
    The resistance of inks to the spectrum of natural light.

    According to the German standard DI 54003/4, the “wool scale” defines eight levels from “very low” to “excellent”.

    Level 3 (moderately light-fast) indicates that the ink can be exposed to sunlight for 4 to 8 days in summer and 2 to 4 weeks in winter without any noticeable fading.

    At the highest level of light-fastness, the ink can withstand exposure to summer sun for more than 18 months.