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http://dx.doi.org/10.14478/ace.2021.1102

A Study of Electro-Optical Properties of Polyester Acrylate-Based Polymer-Dispersed Liquid Crystals Using TIZO/Ag/TIZO Multilayer Transparent Electrodes  

Cho, Jung-Dae (Institute of Photonics & Surface Treatment, Q-Sys Co. Ltd.)
Heo, Gi-Seok (National Center for Nanoprocesses and Equipment, Korea Institute of Industrial Technology)
Hong, Jin-Who (Department of Biochemical & Polymer Engineering, Chosun University)
Publication Information
Applied Chemistry for Engineering / v.33, no.1, 2022 , pp. 50-57 More about this Journal
Abstract
Ti-In-Zn-O (TIZO)/Ag/TIZO multilayer transparent electrodes were prepared on glass substrates at room temperature using RF/DC magnetron sputtering. Obtained multilayer structure comprising TIZO/Ag/TIZO (10 nm/10 nm/40 nm) with the total thickness of 60 nm showed a transmittance of 86.5% at 650 nm and a sheet resistance of 8.1 Ω/□. The multilayer films were expected to be applicable for use in energy-saving smart window based on polymer-dispersed liquid crystal (PDLC) because of their transmittance properties to effectively block infrared rays (heat rays). We investigated the effects of the content ratio of prepolymer, the thickness of the PDLC coating layer, and the ultraviolet (UV) light intensity on electro-optical properties, and the surface morphology of polyester acrylate-based PDLC systems using new TIZO/Ag/TIZO transparent conducting electrodes. A PDLC cell with a thickness of 15 ㎛ PDLC layer photocured at an UV intensity of 1.5 mW/cm2 exhibited good driving voltage, favorable on-state transmittance, and excellent off-haze. The LC droplets formed on the surface of the polymer matrix of the PDLC composite had a size range of 1 to 3 ㎛ capable of efficiently scattering incident light. Also, the PDLC-based smart window manufactured using TIZO/Ag/TIZO multi-layered transparent electrodes in this study exhibited a light brown, which will have an advantage in terms of aesthetics.
Keywords
TIZO/Ag/TIZO multilayer; Smart window; Liquid crystal; PDLC; Surface morphology;
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