Abstract:
Charge transport compounds are described that have a multiple number of hydrazone-bridged heterocyclic groups (especially julolidine groups, carbazole groups, triarylamine groups and (N,N-disubstituted)arylamine groups such as dialkarylamine groups (e. g. dimethylphenylamine; methylethylphenylamine, dipropylphenylamine, ethylepropylphenylamine, ethylbutylnaphthylamine, etc. ), alkyldiarylamine groups (e. g. methyldiphenylamino, ethyldiphenylamino, etc), and triarylamino groups (e. g. , triphenyl amino, trinaphthylamino, etc)) connected by a central bridging group. An example of charge transport compounds are those having the following generic formula: wherein R is selected from the group consisting of julolidine ring groups, carbazole ring groups, and and (N,N-disubstituted)arylamine groups; Q comprises an aromatic hydrazone linking group, such as Y comprises a bridging group between RâQâ groups, such as a bond, carbon atom, nitrogen atom, oxygen atom, sulfur atom, a methylene group; Z is an aryl group, preferably a phenyl group or naphthyl group; X is a linking group, preferably a methylene group, and for example having the formula â(CH ) â (branched or linear), where m is an integer between 0 and 20, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, urethane, urea, an ester group, a âNR group, a CHR group, or a CR R group where R , R , R , and R are, independently, H, an alkyl group, or aryl group; and n is an integer between 2 and 6, inclusive. An organic photoreceptor includes that compound and (b) a charge generating compound; and (c) an electrically conductive substrate.