Electrophotographic charge transport layer compsn. - contg. co-polycarbonate based on bisphenol-alkane and bisphenol, avoiding use of halogenated solvent

摘要

Compsn. for charge transport layers in electrophotographic elements contains polycarbonate resin(s) (I) with recurring units of the formula (I). In (I), R1-2 = H, alkyl or aryl; R3-18 = H, halogen, alkyl or aryl; k and m = positive integers such that k/m = 1-10. Pref., the compsn. also contains a halogen-free solvent; and, as charge transport substance, a styryl cpd. of formula (II); (II) + a hydrazone cpd. of formula (III); a hydrazone cpd. of formula (IV); or a benzidine cpd. of formula (V), (where Ar1-4 and Ar9-12 = opt. substd. aryl gps.; n = 0 or 1; R19-20 = alkyl, phenyl, benzyl or methoxyphenyl; R21 = H, alkyl or O-R; R = linear or branched 5-10C alkyl or 7-10C aralkyl; R22 = alkyl, Ph, MeO, EtO, benzyl, methoxyphenyl, tolyl or naphthyl; R23-24 = H, alkyl, alkoxy or halogen; R25 = H or an opt. substd. alkyl, aralkyl, aryl, condensed polycyclic or heterocyclic gp.; Ar5-8 = an opt. substd. alkyl, aryl, condensed polycyclic or heterocyclic gp., one of Ar5 and Ar6 may = H and Ar5 + Ar6 and/or Ar7 + Ar8 may = ring(s). USE/ADVANTAGE - No halogenated solvent is needed with (I). The compsn. has high speed and gives high quality prints with high resolution.