High-quality electrophotographic applications demand a photoreceptor drum that is “perfect” in many aspects, such as being defect-free—almost to the submicrometer level—environmentally insensitive, and possessing a welldefined photosensitivity that matches the electrophotographic rendering process.Managing hole injection from the conductive substrate is critical to prevent “background and breakdown spots” on the final prints. Typical solutions require a hole-injection barrier layer. These layers need to be environmentally insensitive, resistant to the charge generation layer coating solutions, while allowing transport of photogenerated electrons to the conductive layer to prevent cycling charge buildup.This work describes the development of naphthalene bisimide hole-injection e-barrier layer compositions that can be both coated thick and uniform, and thermally cross-linked. These coating solutions are very stable at normal coating temperature and suitable for the dip coating process. The blocked isocyanate cross-linkers are activated after coating at a temperature above 120 °C. We have developed an offline method to study the kinetics of the cross-linking reaction using the GC headspace analysis technique for optimizing the crosslinked network.
Michel F. Molaire, Wayne T. Ferrar, Randy G. Galipo, Michael Sykes, Theodore Zubil, "Cross-Linked Naphthalene Bisimide “E-Barrier” Layer Compositions Using Blocked Isocyanate Chemistry" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP24), 2008, pp 184 - 187, https://doi.org/10.2352/ISSN.2169-4451.2008.24.1.art00049_1