Infrared radiation absorbing compound, negative lithographic plate precursor, preparation method and application

The invention provides an infrared radiation absorption compound, a negative lithographic plate precursor and a preparation method and application of the infrared radiation absorption compound. According to the infrared radiation absorption compound provided by the invention, an aromatic ring (a benzene ring, a naphthalene ring and the like) is connected with a group with 2-12 carbon atoms and unsaturated double bonds or a polymer chain segment with the molecular weight of 1,000-1,000,000; and when being applied to the plate material, the plate material has good stability, the shelf life of the plate material is prolonged, and the pressrun of the lithographic plate can be improved. After the lithographic plate is scanned and exposed by infrared laser, the lithographic plate can be directly installed on a printing machine for printing without any washing processing step, namely, the lithographic plate is a negative image on-machine developing type treatment-free plate. The treatment-free lithographic plate is