Optically Transparent and Refractive Index-Tunable ZrO₂/Photopolymer Composites Designed for Ultraviolet Nanoimprinting

Abstract

Epoxy-based, acrylate-based, and urethane-based ultraviolet (UV)-curable resins containing acrylate-modified zirconia nanoparticles (ZrO2-NPs) were prepared. UV-cured composite films fabricated using an acrylate-based resin and an epoxy-based resin exhibited a high transmittance >90% at visible and near-infrared wavelengths until the weight fraction of ZrO2-NPs having an average zirconia core diameter of 4.0 nm reached 0.66. Their refractive indices at 633 nm were widely controllable between 1.515 and 1.659 for the acrylate-based composite films and between 1.589 and 1.679 for the epoxy-based composite films. Thin films of the UV-curable composite resins could be transformed by UV nanoimprinting in pentafluoropropane using a fluorinated silica mold. Among the composite resins, the acrylate-based UV-curable composite resins showed facile workability by UV nanoimprinting. The epoxy-based UV-curable composite resins formed pattern shapes independent of the weight fraction of ZrO2-NPs. These results indicated that the acrylate-based and epoxy-based composite films with optical transparency, refractive index controllability, and workability had potential as optical materials of optical devices and as resist materials for dry etching.

Electrohydrodynamic Jet Printing of 1D Photonic Crystals: Part II—Optical Design and Reflectance Characteristics

“…[ 9,32 ] Photopolymers are a mature class of materials with a wide range of commercially available compositions, with refractive indices ranging from 1.315 (fluorinated acrylate polymers) to >1.70 (zirconia nanoparticle‐doped acrylates). [ 33,34 ] In terms of refractive index contrast, the polymeric systems discussed here are significantly lower than the sol–gel systems thus requiring more layers to achieve the same optical response. However, in the context of the e‐jet printing apparatus, the ability to print multiple layers without having to remove the substrate is critical for both printing speed and reduction of errors due to reregistration when replacing the substrate.…”

Synthesis of Transparent Aqueous ZrO2 Nanodispersion with a Controllable Crystalline Phase without Modification for a High-Refractive-Index Nanocomposite Film

“…So far, some semiconductor nanoparticles of metal sulfides such as PbS, FeS, ZnS, − and metal oxides such as TiO 2 , , ZrO 2 , , and ZnO owing to their high refractive index are usually introduced into the polymer matrix to prepare nanocomposites with high refractive index. However, sulfur-containing raw materials such as Na 2 S and H 2 S to prepare PbS, ZnS, and FeS suffer from pollution and storage problems.…”

Effect of organically modified titania and zirconia nanoparticles on characteristics, properties of coating based on acrylic emulsion polymer for outdoor applications

“…The reason may be interactions between nanoparticles and polymer chains. 28,29 As can be seen from Table 5, the coating filled with mixture of m-TiO 2 NPs and m-ZrO 2 NPs had higher reflectance index in comparison with coatings loaded single modified nanoparticles (i.e., m-TiO 2 NPs or m-ZrO 2 NPs). The reason may be ZrO 2 particles having good reflection in the 380-800 nm wavelength range 24 while TiO 2 NPs having light reflection ability well in visible and near infrared region.…”