Photonic structure for dynamic expression of colors and effects

Abstract

Photochromic formulations including a core material and a photochromic layer overlying the core material and forming a particle are provided. The photochromic layer may include a plurality of photochromic materials, including a first photo-responsive pigment characterized by reversible diffuse reflectance at a first central wavelength from 490 nm to 520 nm in response to irradiation by photons of a first characteristic wavelength, a second photo-responsive pigment characterized by reversible diffuse reflectance at a second central wavelength from 570 nm to 590 nm in response to irradiation by photons of a second characteristic wavelength, and a third photo-responsive pigment characterized by reversible diffuse reflectance at a third central wavelength from 450 nm to 495 nm and a fourth central wavelength from 625 nm to 740 nm in response to irradiation by photons of a third characteristic wavelength. The first, second, and third characteristic wavelengths may be different.

Dependencies are inferred from the claim text.