Five-Membered Ring Liquid Crystal Compounds for Low Voltage and Wide Temperature Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current liquid crystal compounds fail to provide a wide temperature range stability, suitable refractive index anisotropy, and low threshold voltage for liquid crystal display devices, particularly in VA and IPS modes, due to limitations in dielectric anisotropy and compatibility with other compounds.
Innovation Solution
A liquid crystal compound with a cyclopentane or tetrahydrofuran ring structure, represented by formula (1), is developed, offering excellent compatibility and characteristics such as low threshold voltage, suitable refractive index anisotropy, and dielectric anisotropy, which are balanced to enhance the performance of liquid crystal display devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional liquid crystal compounds are used, then the liquid crystal composition can be prepared, but the temperature range stability and threshold voltage characteristics are insufficient
Solution Approach 1:
The patent changes the molecular structure parameters by introducing five-membered rings (cyclopentane, tetrahydrofuran) instead of conventional six-membered rings, and by modifying terminal groups and linking structures. These parameter changes result in compounds with both wide temperature range stability and low threshold voltage characteristics, resolving the contradiction between reliability and productivity.
Solution Approach 2:
The patent creates composite liquid crystal compositions by mixing multiple compounds with different molecular structures (cyclopentane rings, tetrahydrofuran rings, various terminal groups). This composite approach allows the composition to achieve both wide temperature stability and low threshold voltage by combining the beneficial properties of different molecular components.
2Productivity
If liquid crystal compounds with large negative dielectric anisotropy are used to decrease driving voltage, then the driving voltage decreases, but the compatibility and stability with other compounds in the composition deteriorate
Solution Approach 1:
The patent applies local quality by designing compounds where different parts of the molecule have specialized functions: the five-membered ring core provides stability and compatibility, while the terminal groups (cyano, alkoxy, fluorinated groups) provide the desired dielectric anisotropy. This local differentiation allows the compound to achieve large negative dielectric anisotropy without sacrificing compatibility and stability with other composition components.
3Productivity
If multiple liquid crystal compounds are mixed to satisfy required characteristics, then the required characteristics can be achieved, but the chemical stability and solubility of the composition deteriorate
Solution Approach 1:
The patent promotes homogeneity by designing liquid crystal compounds with similar molecular structures (all containing five-membered rings and comparable core structures). This structural homogeneity ensures excellent mutual solubility and chemical stability among the mixed compounds, while still allowing the composition to achieve the required optical and electrical characteristics through careful selection of terminal groups and linking structures.
Data Source
AI summary
The invention provides a liquid crystal compound that has an excellent compatibility with other liquid crystal compounds and also has at least one of characteristics such as a high stability to heat, light or the like, a suitable refractive index anisotropy (Δn), a low threshold voltage and a suitable dielectric anisotropy (Δ∈). A compound represented by formula (1).For example, R1 is alkyl having 1 to 10 carbons, R2 is halogen or alkenyl having 2 to 10 carbons; the ring A1, the ring A2 and the ring A3 are 1,4-cyclohexylene or 1,4-phenylene; Z1, Z2 and Z3 are a single bond or alkylene having 1 to 4 carbons; G is —CH2— or —O—; and m is 1, and n and p is 0 or 1.