NOVELTY - Reactive styrene compound (I) is new.    USE - (I) is useful: in a charge transporting film that is useful in a photoelectric conversion device; and in an electrophotographic photoreceptor that is useful in an image forming device for forming an electrostatic latent image (all claimed). (I) is useful in an organic electroluminescence element or device, organic semiconductor layers, memory device and photoelectric device including an organic transistor and an organic solar cell.    ADVANTAGE - (I) exhibits an excellent mechanical strength and charge transport performance property, and provides the electrophotographic photoreceptor with improved extended life and image quality without any deterioration in film shrinkage or aggregation state and electrical characteristics.    DETAILED DESCRIPTION - Reactive styrene compound of formula (F1-(D1)m) (I) is new.    F1 = charge transporting skeleton;    D1 = styrene group of formula (III); and    m = 1-8, preferably 4-6.    L1 = divalent linking group including one or more -C(=O)-O- groups (where L1 is formed by combining -C(=O)-O- with -(CH2)n-); and    n = 1-10.    INDEPENDENT CLAIMS are included for:    (1) a charge transporting film comprising either (I) or its structure derived from (I), or a polymerized or cured film of a composition that contains (I);    (2) an electrophotographic photoreceptor comprising at least a conductive substrate (1), and at least a photosensitive layer (2) provided on the conductive substrate, where an uppermost surface layer is a layer including a polymerized or cured film of a composition that contains one or more kinds of charge transport materials of formula (F2-(D2)m1) (Ia);    (3) a process cartridge comprising the electrophotographic photoreceptor, and being detachable from an image forming apparatus;    (4) an image forming apparatus comprising the electrophotographic photoreceptor, a charging device that charges the electrophotographic photoreceptor, a latent image forming device that forms an electrostatic latent image on the surface of the charged electrophotographic photoreceptor, a developing device that develops the electrostatic latent image formed on the surface of the electrophotographic photoreceptor using a developer including a toner to form a toner image, and a transfer device that transfers the toner image formed on the surface of the electrophotographic photoreceptor to a recording medium; and    (5) producing the electrophotographic photoreceptor comprising forming a coating film by coating a surface to be coated with a coating liquid including a composition that contains (Ia), and forming an uppermost surface layer through polymerizing or curing of the coating film by heating the coating film at 100-170 degrees C.    F2 = charge transporting skeleton;    D2 = styrene group of formula (IIIa); and    m1 = 1-8, preferably 4-6.    L2 = divalent linking group including one or more groups comprising -C(=O)-, -N(R)-, -S- or group formed by combining -C(=O)- with -O-, -N(R)- or -S-; and    R = H, alkyl, aryl or aralkyl.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic partial cross-sectional view of an electrophotographic photoreceptor.    Substrate (1)    Photosensitive layer (2)    Charge generating layer (2A)    Charge transporting layer (2B-1, 2B-2)    Undercoat layer. (4)