280 g gray core paper, 280g blue core paper, 280g Chinese blue core paper, 300g domestic black core paper, 300g double copper white core paper, 350g double copper white core paper, 310G black core paper imported from Germany, 330g black core paper importe
The unsaturated polyester resin is generally a linear polymer compound having an ester bond and an unsaturated double bond, which is obtained by polycondensation of an unsaturated dibasic acid diol or a saturated dibasic acid unsaturated diol.