▎ 摘　　要

NOVELTY - A photoresponsive compound (A) is new. USE - A photoresponsive compound for dispersing agent used for dispersing nano carbon material to dispersion medium for nano carbon material film formation (claimed). ADVANTAGE - The photoresponsive compound (A) application functions as an active ingredient of the dispersing agent which disperses nano carbon material in a dispersion medium, and can desorb nano carbon material by comparatively low energy light irradiation. DETAILED DESCRIPTION - A photoresponsive compound of formula (A) is new. X1, X2=-CONH-, -NHCO-, -COO-, or -OCO-; R=alkyl, fluoroalkyl, OH, or polyethylene glycol; B1=anion; and m=number with which mB becomes - 2 valence. INDEPENDENT CLAIMS are included for: (1) dispersing agent for dispersing nano carbon material to dispersion medium containing water and/or organic solvent, comprising the photoresponsive compound (I) as an active ingredient; (2) dispersion liquid comprising the dispersing agent, nano carbon material, and dispersion medium containing water and/or organic solvent; (3) aggregation of nano carbon material which involves irradiating light which has predetermined wavelength of 250-450 nm to dispersion liquid, desorbing nano carbon material from dispersing agent, and aggregating nano carbon material in the dispersion medium; and (4) manufacture of nano carbon-material film which involves making dispersion liquid contact a base material, irradiating light which has predetermined wavelength of 250-450 nm to dispersion liquid, and forming the film of nano carbon material on the surface of the base material that contacts the dispersion liquid.