Broadband Reflective Liquid Crystal Films Prepared by Rapid Inkjet Printing and Superposition Polymerization

Abstract

Inkjet printing is a non-contact, material saving and on-demand material manufacturing technology, which is able to be applied to the fabrication of functional materials with high efficiency. A new method for preparing broadband reflective cholesteric films based on inkjet printing and non-stick technology was proposed in this paper. The feasibility of automatic mixing of liquid crystal and doped materials in inkjet printing was studied. The spectral data of samples prepared by manual mixing and automatic mixing by inkjet printing were compared. It was found that the spectral error of the printed film was only less than 0.17 wt%, which reached or even exceeded the effect of manual mixing. The feasibility of preparing liquid crystal films with broadband reflection characteristics by stacking polymerization based on in situ UV polymerization and non-stick technology was verified. By changing the printing amount of chiral doped ink, the bandwidth of PSCLC film can be accurately controlled. This technology is expected to play an important role in scientific research and practical application.

Recent advances in solar infrared light regulating smart windows based on organic materials

“…[30] Another option to create broader reflection bands is printing multiple ChLC layers with peak reflective wavelengths ranging from 800 to 2000 nm on top of each other. [31] However, each additional layer applied tends to diminish the transmission of visible light and increase haze. Stacking freestanding narrowband NIR reflective layers also formed a thermally stable broadband reflector withstanding temperatures of up to 100°C.…”

“…Another option to create broader reflection bands is printing multiple ChLC layers with peak reflective wavelengths ranging from 800 to 2000 nm on top of each other [31] . However, each additional layer applied tends to diminish the transmission of visible light and increase haze.…”

Research Progress of Cholesteric Liquid Crystals with Broadband Reflection

“…Recently, a new approach to the preparation of broadband reflective ChLC films based on inkjet printing and non-stick technology was proposed in our research (as shown in Figure 2 ) [ 29 ]. We filled the separate C, M, Y channels with chiral molecules, polymerizable monomers and liquid crystals, respectively, and controlled the inkjet volume by software (Acro-rip).…”

“…The advantages of the single-pitch multilayer stacking method are that the preparation process is very simple and the wavelength and the reflection range of each film are controllable. However, the stacked multilayer system is not a direct combination of monolayer characteristics, and there is certain diffusion between the film interfaces, which, to a certain extent, affects the plane orientation of Recently, a new approach to the preparation of broadband reflective ChLC films based on inkjet printing and non-stick technology was proposed in our research (as shown in Figure 2) [29]. We filled the separate C, M, Y channels with chiral molecules, polymerizable monomers and liquid crystals, respectively, and controlled the inkjet volume by software (Acro-rip).…”