Polyimide Alignment Film with Polymer Protrusions for LCD Vertical Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current liquid crystal display (LCD) technologies face contamination issues due to residual reactive mesogen from free radical polymerization, leading to ghosting and reduced panel quality in polymer stabilization vertical alignment (PSVA) techniques.
Innovation Solution
A material alignment film comprising a polyamic acid with an aromatic fused ring structure, a polymerizable monomer with an aromatic fused ring structure, and a solvent is used to create a polyimide film with polymer protrusions, allowing vertical alignment of liquid crystals without contaminating them, and generating a pre-inclination angle through UV irradiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If reactive mesogen is blended in liquid crystal molecules for polymer stabilization vertical alignment, then vertical alignment and pre-inclination angle are achieved, but residual reactive mesogen contaminates liquid crystal causing ghost and reducing panel quality
Solution Approach 1:
The patent extracts the polymerizable monomer from the liquid crystal composition and places it exclusively in the alignment film layer. The alignment film contains the polymerizable monomer that polymerizes under UV irradiation to create the alignment structure, while the liquid crystal layer remains free of polymerizable components, eliminating contamination and ghosting issues.
Solution Approach 2:
The patent segments the system into two distinct functional layers: an alignment film containing the polymerizable monomer for structure formation, and a liquid crystal layer free of polymerizable components for optimal optical performance. This segmentation prevents cross-contamination while maintaining the desired vertical alignment effect.
2Manufacturing precision
If polymerizable monomer is used in alignment film for vertical alignment, then pre-inclination angle is generated, but risk of monomer contaminating liquid crystal molecules increases
Solution Approach 1:
The patent removes the polymerizable monomer from the liquid crystal composition and confines it to the alignment film only. This extraction eliminates the contamination pathway while preserving the alignment function, as the monomer resides exclusively in the alignment film where it polymerizes to create the desired vertical alignment structure.
3Manufacturing precision
If protrusions or slits are designed on CF side for vertical alignment control, then plane control is achieved, but cost increases and light transmittance is reduced
Solution Approach 1:
The patent replaces the mechanical approach of creating protrusions or slits in the CF substrate with a chemical/polymerization approach. The alignment film contains polymerizable monomer that forms a polymer network under UV irradiation, creating the alignment structure without requiring mechanical modifications to the CF substrate, thereby reducing complexity and maintaining light transmittance.
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
This method enhances the quality of the liquid crystal display panel by ensuring a simple structure with good alignment and eliminating the risk of polymerizable monomer contamination, resulting in excellent display quality.
Implementation Method 1
after the reactive mesogen occurs the free radical polymerization under the UV irradiation
Implementation Method 2
performing a specific UV irradiation, at this time, the reactive mesogen 200 polymerizes to form a polymer network
Implementation Method 3
refracting light of the backlight module to produce frames
Data Source
AI summary
The present application provides a material of alignment film, a method of fabricating a liquid crystal display panel, and a liquid crystal display panel. The material of alignment film of the present application is obtained by mixing a polymerizable monomer in the polyamic acid solution, thus is easy to fabricate. The method of fabricating the liquid crystal display panel of the present application obtains an alignment film including a polyimide film and polymer protrusions located on a surface of the polyimide film by coating the material of alignment film on a substrate, and going through a series of processes; the alignment film can allow liquid crystal molecules arrange in vertical alignment and generate a pre-inclination angle, and a risk of the polymerizable monomer contaminating the liquid crystal molecules does not exist, so as to enhance quality of the liquid crystal display panel. The liquid crystal display panel of the present application has a simple structure and good alignment effect, and has excellent display quality.