Diamine compounds and electrophotographic photoreceptor

A electrophotographic photoreceptor comprising an electrically conductive substrate having a photosensitive layer thereon which contains a binder resin, a charge generating material or a sensitizing dye, and a diamine compound of the following formula (1):

• ##STR569## wherein R.sub.1 is a hydrogen atom, a C.sub.1-4 alkyl group or a C.sub.1-4 alkoxy group, each of A.sub.1, A.sub.2 and A.sub.3 which are independent of one another, is a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a group of the following formula (2):
• ##STR570## wherein R.sub.1 is as defined above, and X is a substituted or unsubstituted arylene group or a substituted or unsubstituted heterocyclic bivalent group, and wherein the substituent for the substituted alkyl group for each of A.sub.1, A.sub.2 and A.sub.3 is a C.sub.1-4 alkoxy group which may be substituted by a C.sub.1-4 alkoxy group or a halogen atom, a C.sub.5-6 cycloalkyl group, a benzyl or phenyl group which may be substituted by a C.sub.1-4 alkyl group, a C.sub.1-4 alkoxy group or a halogen atom;
• the substituent for the substituted aryl group for each of A.sub.1, A.sub.2 and A.sub.3 is a C.sub.1-4 alkyl or alkoxy group which may be substituted by a C.sub.1-4 alkoxy group or a halogen atom, a C.sub.5-6 cycloalkyl group, a benzyl or phenyl group which may be substituted by a C.sub.1-4 alkyl or alkoxy group or a halogen atom, or a halogen atom;
• and the substituent for the substituted arylene or heterocyclic bivalent group for X is the some as the above-identified substituent for the substituted aryl group for each of A.sub.1, A.sub.2 and A.sub.3.