US Patent 9777201 Polymer formulations for use with electro-optic media

Polymer formulations including urethane acrylates, adhesion promoters, and conductive monomers. By selecting suitable conductive monomers, it is possible to achieve formulations having a volume resistivity from 106 to 1010 Ohm·cm after being conditioned for one week at 25° C. and 50% relative humidity. Such formulations are suitable for incorporation into electro-optic materials, such as electro-optic displays or variable transmission films, e.g., for architectural applications. In other embodiments, the formulations additionally include metal oxide nanoparticles to alter the refractive index and/or conductivity. The addition of certain metal nanoparticles additionally facilitates non-destructive measurement of layer thickness using X-ray fluorescence spectroscopy.