Polymerizable Liquid Crystal Composition with Cardo-Type Fluorene Monomer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polymerizable liquid crystal compositions struggle to achieve uniform homeotropic alignment without an alignment film and exhibit reduced chemical strengths such as heat resistance and solvent resistance.
Innovation Solution
Incorporating a cardo-type fluorene monomer into the polymerizable liquid crystal composition, which allows for uniform homeotropic alignment on glass or plastic substrates without long-chain alkyl groups or inorganic surface treatments, and minimizing the use of monofunctional polymerizable compounds to enhance chemical stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a polymerizable liquid crystal composition is used to achieve homeotropic alignment without an alignment film, then the device complexity is reduced, but the manufacturing precision of alignment uniformity deteriorates
Solution Approach 1:
The liquid crystal composition itself provides the alignment function through its molecular structure and interaction with the substrate, eliminating the need for a separate alignment film. The composition self-organizes to achieve homeotropic alignment directly on the substrate surface.
Solution Approach 2:
The invention uses a composite liquid crystal composition containing multiple components (cyclic carbonate compound, hydroxyl-terminated polymer, and liquid crystal compound) that work synergistically to achieve both alignment and optical functions without requiring additional alignment films.
2Ease of manufacture
If monofunctional polymerizable liquid crystal compounds are used to simplify the composition, then the ease of manufacture is improved, but the chemical strength and heat resistance deteriorate
Solution Approach 1:
The invention introduces polyfunctional monomers with multiple polymerizable groups at specific positions within the liquid crystal molecule, creating local regions of enhanced crosslinking density that provide improved heat and solvent resistance while maintaining overall composition simplicity.
Solution Approach 2:
The composition combines monofunctional and polyfunctional polymerizable liquid crystal compounds in a controlled ratio, where the polyfunctional compounds form a crosslinked network that enhances chemical strength while the monofunctional compounds maintain processability and simplicity.
3Stability of the object's composition
If the liquid crystal composition is polymerized to fix alignment, then the stability of alignment is improved, but the loss of substance during polymerization increases
Solution Approach 1:
The invention optimizes polymerization parameters including temperature, time, and initiator concentration to achieve complete or near-complete conversion of monomers to polymer, minimizing unreacted monomer loss while ensuring stable alignment fixation through thorough polymerization.
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 resulting polymerizable liquid crystal composition achieves improved heat resistance and solvent resistance, maintaining alignment and optical properties even without an alignment film, making it suitable for optical compensation elements.
Implementation Method 1
Polymerizable liquid crystal compounds having a liquid crystal phase can be used to obtain a polymer having optical compensation functions through polymerization. That is, the alignment of the liquid crystal compound is fixed through polymerization.
Data Source
AI summary
A polymerizable liquid crystal composition is presented which can form a polymer that allows formation of a uniform homeotropic alignment even without forming an alignment film on the supporting substrate and has excellent chemical strengths such as heat resistance and solvent resistance.The polymerizable liquid crystal composition includes at least one type of polyfunctional polymerizable liquid crystal compound and a cardo-type fluorene monomer, wherein based on a total amount of the polyfunctional polymerizable liquid crystal compound, a content of a monofunctional polymerizable liquid compound is less than 5.0% by weight.