| abstract |
The present invention provides charge transport compounds that have a multiplennumber of hydrazone-bridged heterocyclic groups (especially julolidine groups,ncarbazole groups, triarylamine groups and (N,N-disubstituted)arylamine groups such asndialkarylamine groups (e.g. dimethylphenylamine; methylethylphenylamine,ndipropylphenylamine, ethylepropylphenylamine, ethylbutylnaphthylamine, etc.),nalkyldiarylamine groups (e.g. methyldiphenylamino, ethyldiphenylamino, etc), andntriarylamino groups (e.g., triphenyl amino, trinaphthylamino, etc)) connected by ancentral bridging group. An example of charge transport compounds are those having thenfollowing generic formula:n (R-Q)n-Y nwherein R is selected from the group consisting of julolidine ring groups, carbazole ringngroups, and and (N,N-disubstituted)arylamine groups; n Q comprises an aromatic hydrazone linking group, such asn nY comprisesna bridging group between R-Q- groups, such as a bond, carbon atom, nitrogen atom,noxygen atom, sulfur atom, a methylene group; Z is an aryl group, preferably a phenylngroup or naphthyl group; X is a linking group, preferably a methylene group, and fornexample having the formulan -(CH 2 ) m - n(branched or linear), where m is an integer between 0 and 20, inclusive, andnone or more of the methylene groups is optionally replaced by an oxygen atom, ancarbonyl group, urethane, urea, an ester group, a -NR 6 group, a CHR 7 group, or a CR 8 R 9 ngroup where R 6 , R 7 , R 8 , and R 9 are, independently, H, an alkyl group, or aryl group;nand n is an integer between 2 and 6, inclusive. An organic photoreceptor includes thatn(a) a charge transport compound and (b) a charge generating compound; and (c) annelectrically conductive substrate. Corresponding electrophotographic apparatuses andnimaging methods are also described. |