Polyester resin is an abbreviation for unsaturated polyester adhesive. The unsaturated polyester adhesive is mainly composed of an unsaturated polyester resin, an initiator, a promoter, a filler, a thixotropic agent and the like. a linear structure (see linear polymer) polyester resin containing -CH=CH- double bond in the main chain, which can be mixed with an ethylenic monomer such as styrene, acrylate, vinyl acetate, etc. Under the action of the initiator and the accelerator, it is polymerized into an insoluble and infusible product at normal temperature. The English abbreviation for unsaturated polyester is UP. Mainly used in the production of coil coatings.