PURPOSE: To obtain a new compound useful as a sensitizer for a photopolymerization initiator to be used in the field of recording materials, etc., such as photosensitive protection film, printing plate, photoresist and proof.

CONSTITUTION: The compound of formula I or formula II (R1 to R3 are 1-20C alkyl; R4 is H, 1-40C alkyl or 6-40C aryl; (n) is 3-20; X is O, O-CO, etc.; R7 is 1-40C alkylene; (m) is 0 or 1), e.g. 4-diethylamino-4'-N-n-butyl-N-(3- chloropropyl)aminobenzophenone. This compound of formula I can be produced by reacting an amide compound with a dialkylaniline compound and reacting the resultant compound of formula III (Y is halogen, hydroxy, alkylsulfonyl, etc.) with a compound of the formula H-X-R4 in the presence of a condensation agent (e.g. sodium bicarbonate) in a solvent (e.g. water) at 35-120°C. The compound of formula I is useful as a sensitizer having high molecular weight and resistant to evaporation even by heating at high temperature.