Practical Preparation of Elastomer-Immobilized Nonclose-Packed Colloidal Photonic Crystal Films with Various Uniform Colors

Abstract

Colloidal photonic crystals, which are three-dimensional periodic structures of monodisperse submicron-sized particles, are expected to be suitable for novel photonic applications and color materials. In particular, nonclose-packed colloidal photonic crystals immobilized in elastomers exhibit significant potential for use in tunable photonic applications and strain sensors that detect strain based on color change. This paper reports a practical method for preparing elastomer-immobilized nonclose-packed colloidal photonic crystal films with various uniform Bragg reflection colors using one kind of gel-immobilized nonclose-packed colloidal photonic crystal film. The degree of swelling was controlled by the mixing ratio of the precursor solutions, which used a mixture of solutions with high and low affinities for the gel film as the swelling solvent. This facilitated color tuning over a wide range, enabling the facile preparation of elastomer-immobilized nonclose-packed colloidal photonic crystal films with various uniform colors via subsequent photopolymerization. The present preparation method can contribute to the development of practical applications of elastomer-immobilized tunable colloidal photonic crystals and sensors.

Van der Waals Colloidal Crystals

“…In general, well-crystallized dielectric colloids with a relatively low RI contrast have a very narrow PBG and low Bragg reflectivity, [54][55][56] which in turn restricts their possible practical applications, particularly outdoors. In contrast, the inclusions of the subwavelength-scale Au core can strengthen the dipolar resonance, [45,[57][58][59] consequently improving the effective electric permittivity of each colloid and the resultant RI contrast.…”

Angle-Independent Color Change in Thermoresponsive Gel-Immobilized Colloidal Amorphous Film Attached to PET Substrate

“…In contrast to general dyes and pigments, structural colors have unique properties such as nonfading against ultraviolet (UV) light and color tuning according to structural changes; hence, they are expected to be employed as novel colorants and sensors [ 5 , 6 , 7 ]. Extensive research has been conducted on the preparation and application of colloidal crystals with artificial structural colors [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. Colloidal crystals utilize periodically arranged monodisperse submicrometer particles to exhibit vivid reflective colors.…”