Polymerizable Composition for Liquid Crystal Displays Using Fluorosurfactant
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing polymerizable compositions for liquid crystal displays suffer from issues such as crystal precipitation, storage stability, and uneven film formation due to surfactant offset, leading to poor appearance and display quality.
Innovation Solution
A polymerizable composition combining a specific fluorosurfactant with a polymerizable compound having a specific structure, characterized by reverse wavelength dispersion and a fluorosurfactant with a weight average molecular weight of 2,500 to 30,000, which enhances solubility and storage stability, and improves surface leveling properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If polymerizable liquid crystal compounds with reverse or weak wavelength dispersion are added to polymerizable compositions, then the optical properties for improved viewing angle are achieved, but crystal precipitation occurs and storage stability becomes insufficient
Solution Approach 1:
The patent introduces a specific fluorosurfactant as an intermediary substance to mediate between the polymerizable liquid crystal compound and the polymerizable composition. This fluorosurfactant acts as a solubility enhancer and stabilizer, allowing the liquid crystal compound to remain dissolved and preventing crystal precipitation while maintaining the desired optical properties.
Solution Approach 2:
The patent optimizes specific parameters including the fluorosurfactant concentration (0.01-5 wt%), molecular weight (2,500-30,000), and chemical structure to achieve the right balance between solubility enhancement and optical property maintenance. By carefully controlling these parameters, the composition achieves both storage stability and desired optical characteristics.
2Manufacturing precision
If specific surfactants are added to polymerizable liquid crystal compound compositions to solve coating unevenness, then surface leveling is improved, but surfactant offset occurs on substrates causing poor appearance
Solution Approach 1:
The fluorosurfactant serves as an intermediary that provides surface leveling functionality without the harmful offset effect. Its specific molecular structure and properties allow it to remain embedded in the polymerized film rather than migrating to the substrate surface, thus eliminating the offset problem while maintaining coating uniformity.
Solution Approach 2:
The patent utilizes the local quality of the fluorosurfactant molecules, which have specific hydrophilic and hydrophobic regions that allow them to position themselves appropriately within the polymer matrix. This localized arrangement provides surface leveling where needed while preventing migration to the substrate interface.
3Adaptability or versatility
If multiple polymerizable compounds are used to meet required optical properties and performance characteristics, then the comprehensive performance is improved, but the composition complexity increases and solubility issues arise
Solution Approach 1:
The fluorosurfactant performs multiple functions simultaneously: it enhances solubility of the polymerizable liquid crystal compound, prevents crystal precipitation, improves storage stability, and provides surface leveling. This multi-functionality reduces the need for multiple separate additives, thereby simplifying the overall composition while maintaining comprehensive performance.
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 composition achieves excellent solubility and storage stability, reducing surfactant offset and unevenness, resulting in high-quality, optically anisotropic films with improved productivity and appearance.
Implementation Method 1
A polymerizable composition comprising: a polymerizable compound having one polymerizable group or two or more polymerizable groups and satisfying formula (I)... at least one fluorosurfactant selected from the group consisting of copolymers (III)... excellent solubility, causes no precipitation of crystals, and has high storage stability
Implementation Method 2
To improve the viewing angle of liquid crystal displays, it is necessary for retardation films to show birefringence with weak or reverse wavelength dispersion. Various polymerizable liquid crystal compounds with reverse or weak wavelength dispersion have been developed
Implementation Method 3
Another important technique to solve the coating unevenness problem and the offset problem simultaneously is to select an optimal surfactant... improves surface leveling properties
Implementation Method 4
by aligning a polymerizable composition containing a polymerizable compound into a liquid crystal state and then polymerizing the resulting polymerizable composition, a polymer with uniform alignment can be produced
Data Source
AI summary
The present invention provides a polymerizable composition containing a specific polymerizable compound and a fluorosurfactant having a specific polyoxyalkylene skeleton and having specific molecular weight. The invention also provides an optically anisotropic body, a retardation film, an antireflective film, and a liquid crystal display device that are produced using the polymerizable composition of the present invention. The present invention is useful because, when an optically anisotropic body is produced by photo-polymerization of the polymerizable composition, three features including the leveling properties of the surface of the optically anisotropic body, offset onto the substrate, and liquid crystal alignment can be improved simultaneously.