New protophane(s) giving stable mixture with binder, even in high concentration, without losing photoconductivity

Protophanes (IA) which are bis-, tris- or tetrakis-pyrene or -indole compounds of formula (D)1-Y (I) with specified substituents are new. In (I), l = 2, 3 or 4; D = an aromatic group of formula (II) or (III); R = hydrogen (H), 1-6 carbon (C) alkyl, (substituted) phenyl or phenyl-(1-6C) alkyl; k = 0 or 1; A = 1,2-eth(en)ylene; B = (substituted) 1,2-phenylene; or C(A)-C(B) = a linear condensed, optionally substituted naphthalene unit; S = substituent(s) or a condensed, optionally substituted benzene or thiophene unit; Y = a di-, tri- or tetravalent organic group or, if l = 2, Y may also = a single bond. Protophanes (IB) of formula (I; D = a (II) group; R = H; k = 0; Y = a single bond) are excluded. Also claimed are: (a) charge transfer complexes containing compound(s) (IA) and/or (IB) and organic low-molecular compound(s) as electron acceptor; (b) a method of producing the charge transfer complexes; and (c) photoconducting material containing (IA) or a charge transfer complex a nd 50 deg C.