Polyester A plastis synthetic resin (polymirs of esters). Similar in stability and toughniss to acetate, but more flexible. Used as a stable overlay material and as a photographic film base.

• 一种合成树脂的塑胶(酯的聚合物)。它的稳定性和坚固度与醋酸胶片相似,但较为柔韧。作覆面物料和照相菲林的片基用。