NEW MATERIAL:Anthraquinone derivatives of formula I, wherein R, R' are each H, alkyl, alkoxy, nitro, cyano, halogen.

USE: Dyes for coloration of low-molecular materials such as liquid crystals, min eral oil and sheets, fibers and other moldings composed of natural or synthetic high-molecular materials such as cellulose, polyesters or polystyrene. Since they have absorption bands in a near-infrared ray region, they can be used as infrared absorber.

PREPARATION: A compd. of formula II (wherein Y is halogen) is reacted with a compd. of formula III to produce a compd. of formula IV or its anhydride which is then reacted with a compd. of formula V in a solvent to effect imidation, thus obtaining the desired compd.