Phthalic anhydride, also known as phthalic anhydride, is an important chemical raw material. The main use of phthalic anhydride in my country is to produce phthalate plasticizers, followed by alkyd resins and amino resin coatings; phthalic anhydride can be used in the production of unsaturated polyesters and in the dye industry to synthesize anthraquinone.