Silsesquioxanes are a class of silicone polymers that are useful as abrasion resistant overcoats for organic photoreceptors. We have manipulated the electrical properties of this sol-gel matrix by incorporating a solid electrolyte. Solid electrolytes, also referred to as solid ionic conductors, are materials in which electrical conductivity is provided by the motion of ions. We chose (3-glycidoxypropyl)trimethoxysilane (GPS) as the most suitable commercially available monomer to form the polymer matrix for lithium iodide migration. This epoxysilane contains two ether oxygen atoms for coordination to low lattice energy salts. A good correlation was observed between the level of GPS and the electrical properties of the coating, with increasing concentration of GPS in the silsesquioxane resulting in decreased resistivity. The silsesquioxane is a hard material and the resistivity remained relatively high, between 1010–1013 ohm-cm. However, this is a desirable resistivity for maintaining image quality with an overcoated photoreceptor.
W. T. Ferrar, D. S. Weiss, J. R. Cowdery, L. G. Parton, "Ionic Conduction in Sol-Gel Overcoats for Organic Photoreceptors" in Journal of Imaging Science and Technology, 2000, pp 429 - 432, https://doi.org/10.2352/J.ImagingSci.Technol.2000.44.5.art00009