Polychem 7423-65 Polyester OPC Polymers Polyester Coatings >> Solventborne 150 solvent : EB POLYCHEM 7423-65 is an oil-free polyester which offers good cure response and durability in aminoplast cross linked bake systems. Industrial bake enamels Oil-free polyester. Used in aminoplast crosslinked bake systems such as industrial bake enamels. Offers good cure response and durability.