Polymerizable Compound with Conjugated Bonds for Liquid Crystal Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current polymerizable compounds used in liquid crystal display devices face challenges in achieving a balance between high polymerization reactivity, solubility, and desired physical properties such as maximum temperature, viscosity, optical anisotropy, and dielectric anisotropy, which affects the performance and longevity of the devices.
Innovation Solution
A polymerizable compound with a conjugated double or triple bond is developed, combined with specific liquid crystal compounds to form a polymerizable composition that enhances polymerization reactivity, solubility, and physical properties, including a high maximum temperature of the nematic phase, low minimum temperature, small viscosity, suitable optical anisotropy, and large dielectric anisotropy, thereby improving the performance of liquid crystal display devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the solubility of polymerizable compound in liquid crystal composition is increased, then the polymerization reactivity is decreased
Solution Approach 1:
The patent changes the chemical structure parameters of the polymerizable compound by introducing specific molecular groups (cyclic carbonate, carbonyl, cyano, or halogen groups) at designated positions in the molecular structure. This structural parameter modification allows the compound to achieve both high solubility in the liquid crystal composition and maintain high polymerization reactivity, resolving the inverse relationship between these two properties.
2Reliability
If a polymer is formed in the liquid crystal composition by polymerization of polymerizable compound, then the response time is decreased and image burn-in is improved, but the balance between solubility and polymerization reactivity becomes difficult to achieve
Solution Approach 1:
The patent applies local quality by introducing specific functional groups (cyclic carbonate, carbonyl, cyano, or halogen groups) at specific positions (R1 to R6) in the polymerizable compound's molecular structure. This localized structural modification enables the compound to simultaneously achieve high solubility in the liquid crystal composition and maintain high polymerization reactivity, thereby simplifying the overall system while improving reliability.
3Temperature
If the maximum temperature of nematic phase is increased and minimum temperature is decreased, then the temperature range for device operation is widened, but the physical properties such as viscosity, optical anisotropy, and dielectric anisotropy become harder to balance
Solution Approach 1:
The patent creates a composite liquid crystal composition by combining the specifically structured polymerizable compound (with cyclic carbonate, carbonyl, cyano, or halogen groups) with liquid crystal compounds. This composite approach enables the system to achieve a wide nematic phase temperature range while simultaneously maintaining balanced physical properties including viscosity, optical anisotropy, and dielectric anisotropy, thereby widening the operational temperature range without increasing device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new polymerizable compound and composition achieve a high conversion yield, improved solubility, and balanced physical properties, resulting in a liquid crystal display device with a wide temperature range, short response time, large voltage holding ratio, low threshold voltage, and long service life.
Implementation Method 1
A polymer is formed in the liquid crystal composition by the irradiation with ultraviolet light and by the polymerization of the polymerizable compound
Data Source
AI summary
SubjectIt is to provide a polymerizable compound having a high polymerization reactivity, a high conversion yield and a high solubility in a liquid crystal composition, a polymerizable composition including this compound, a liquid crystal composite prepared from this polymerizable composition and a liquid crystal display device containing this composite.Means for solving the SubjectA compound represented by formula (1), the liquid crystal composition and the liquid crystal display device.In the formula, for example, ring A1, ring A2 and ring A4 are phenylene or cyclohexylene; Sp1 and Sp2 are a single bond or alkylene having 1 to 6 carbons; Z1 and Z2 are —CH═CH— or —C≡C—; a is 1, b is 0; and P1 and P2 are a polymerizable group.