An optical security film device and a method of making the same

Abstract

This invention relates to the field of anti-counterfeiting film technology, specifically to an optical anti-counterfeiting film device and its preparation method, comprising a polymer-dispersed liquid crystal, a carrier layer, a pattern layer, a protective layer, and a substrate layer; wherein the polymer-dispersed liquid crystal, also known as PDLC, typically contains liquid crystal, polymer, and spacers. The spacers are usually micron-sized microspheres randomly distributed in the PDLC system, and the liquid crystal is usually randomly dispersed in micron-sized droplets in the cured polymer. The beneficial effects of this invention are: by setting the liquid crystal to be an optically and dielectrically anisotropic material, the liquid crystal molecules can change their orientation under the action of an electric field, thereby changing the refractive index and realizing the change of the transmittance or color of the PDLC; and through the combination of the substrate layer, carrier layer, pattern layer, polymer-dispersed liquid crystal, protective layer, adhesive, and functional additives, the device can generate structural colors, and the difference in the electric field response speed of the liquid crystal at different positions is small.

Images