Effects of particle form on the angular dependence of transmittance for needle-like TiO₂ particle arrayed composite films

Abstract

Composite films with an array of needle like TiO₂ particles in urethane resin matrix were fabricated by applying AC bias. The resulting composite films showed angular dependence of transmittance in the visible-NIR wavelength range. The angular dependence of transmittance of the film increased with the increase in the aspect ratio of the TiO₂ particles. The composite films using needle like TiO₂ particles with an aspect ratio of 19 indicated that the transmittance changed by 25.4% between 0 and 60° at a wavelength of 500 nm.