Preparation method of benzophenone acid derivate and used production device

The invention discloses a preparation method of a benzophenone acid derivative and a used production device. The preparation method comprises the following steps: uniformly mixing N,N-dialkyl m-aminophenol, phthalic anhydride and a reaction solvent in a raw material mixing tank, thereby obtaining an original material; heating after fully filling a tubular reactor with the reaction solvent; injecting the original material into the tubular reactor for reaction, and enabling the volume of the original material entering the tubular reactor to be equal to the volume of the reaction material spilling out of the tubular reactor, thereby realizing continuity of a reaction; flushing the tubular reactor by utilizing the reaction solvent, thereby enabling the reaction material reserved in the tubular reactor to be wholly spilled into a reaction solution storage tank; pulping and filtering after cooling the reaction material to room temperature, and drying after washing a filter cake by using a washing solvent, thereby obtaining the benzophenone derivative.