What is the heat discoloration resistance and heat yellowing resistance test?

⑴Test method: After softening and finishing the fabric (colored fabric for heat-resistant discoloration; bleached fabric for heat-resistant yellowing), bake (or press) at (185±2) ℃ for 3 minutes, and then press Judge the law.

▼The heat-resistant discoloration resistance is evaluated by comparing the hue difference of heated and unheated fabrics with a gray scale of discoloration and fading.

▼Heat yellowing resistance is to judge the degree of yellowing of the heated fabric relative to the unheated fabric, and use the gray scale for staining to evaluate the grade. It can also measure the whiteness of heated and unheated fabrics, and evaluate the yellowing performance based on the decrease in whiteness.

⑵Description:

▼The fabric heat treatment can use hot air dryer, oven, sublimation fastness tester, scorch tester and other equipment.

▼According to different fiber types, the heat treatment temperature, time and other conditions should be different, which can be determined according to the situation, and the test conditions should be indicated in the report.