This standard specifies the test methods of discoloration degree under approximate sunlight and ultraviolet for light-colored and white products which are used as upper material and sole material.
This standard specifies Method A and Method B for testing. The latter is not applicable to arbitration and precise scientific research development work.
This standard is applicable to the test of white and light-colored upper and sole material used for footwear.
2. Normative References
The following normative documents contain provisions which, through reference in this standard, constitute provisions of this standard. At the time of publication, all editions indicated are valid. All standards are subject to revision, and parties concerned are encouraged to discuss the possibility of applying the latest edition of the following standards.
GB 250-1995 Gray Scale for Assessing Change in Colour
3. Principle
3.1 Method A (sunlamp method)
Based on the result that light-colored or white products are prone to be yellow in color exposed to long-time natural sunlight, and under the simulated natural environment by sunlamp and heating and temperature regulating device, within the specified time, observe the changes of specimen surface in color to determine the degree of discoloration, so that the material capability of discoloration in sunlight exposure may be judged.
3.2 Method B (ultraviolet light tube method)
