Polycarbonate board UV protection

Generally, there are two kinds of resins purchased by the sheet production factory, one is a common PC resin, and the other is a PC resin containing an anti-UV additive. The selected UV-resistant additives are as large as the following:

(1) Salicylates such as p-tert-butylphenyl salicylate (TBS).

(2) benzophenones such as 2-hydroxy-4-methoxybenzophenone (UV-9); 2-hydroxy-4-methoxy-2'-carboxybenzophenone (UV- 207); 2-hydroxy-4-n-octyloxybenzophenone (UV-531).

(3) benzotriazoles such as 2-(2'-hydroxy)-3,7,5'-di-tert-butylphenylbenzotriazole (UV-320); 2-(2'-hydroxy-5 '-tert-octylphenyl)benzotriazole (uV-5411) and the like. The PC board is prone to internal stresses, and the presence or absence of internal stress on the sheet can be checked by carbon tetrachloride immersion and polarized light. The internal stresses present in the sheet can be eliminated by annealing.