Why is the more suitable  Optical Brightener for EVA foam shoe material is Optical Brightener KCB?

First of all, the processing temperature of EVA is 210-230 degrees, so the brightener whose melting point is lower than 210 degrees can be excluded from the beginning. This leaves only: OB-1, KCB, KSN, 127.

Then let's take a look at the color shade. If people like natural to choose a blue-light one. Then, the reddish KSN can only say goodbye. The remaining players are: OB-1, KCB, 127.

Next is stability. Stability points should be divided into two points of view: 1. Weather resistance, which means that the long-term wind and sun are still bright and white as new; 2. Segregation resistance, which means that it cannot be squeezed several times. The molecules of the fluorescent whitening agent are only Ran out. We all know that the shoe material EVA is originally made for the sole, but it is conceivable that it will be squeezed every day. The precipitation resistance of OB-1 is not good, and the weather resistance of 127 is poor. Through this round of screening, only KCB is left.