US Patent 7232634 Imaging member

A charge transport layer for an imaging member comprising a charge transport material with a nitrogen molecular defense system not exhibiting early onset of charge transport layer fatigue cracking. The nitrogen molecular defense system includes attaching bulky organic groups to charge transport materials. The bulky groups aid in preventing recrystallization of the charge transport molecule and shield the nitrogen from molecular attack, such as by oxidation. The charge transport layer exhibits excellent wear resistance, excellent electrical performance, and outstanding print quality.