Phase Difference Plate Using Photo-Aligned Polymer for Light Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing phase difference plates for organic EL display devices suffer from deteriorated light resistance due to the type of rod-like liquid crystalline compounds or functional groups used, particularly affecting their optical characteristics and durability.
Innovation Solution
A phase difference plate is developed using a polymer with a specific photo-alignment group and a polymerizable liquid crystal compound exhibiting reciprocal wavelength dispersion, formed from a composition that includes a repeating unit with a double bond structure of C═C or C═N, such as a cinnamate or chalcone group, and a liquid crystal compound represented by Formula (3), which improves light resistance and optical characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional phase difference plate uses rod-like liquid crystalline compounds or standard functional groups, then the manufacturing process is simple, but the light resistance deteriorates under high light emission intensity
Solution Approach 1:
The patent uses a composite material system consisting of a polymer matrix containing a photo-alignment group (such as cinnamate or chalcone groups) combined with a polymerizable liquid crystal compound. This composite structure provides both the alignment function and the desired optical properties while maintaining light resistance under high emission intensity conditions.
Solution Approach 2:
The patent changes the chemical parameters of the photo-alignment group by selecting specific functional groups (cinnamate or chalcone) with defined molecular structures. This parameter change optimizes the light resistance and optical characteristics of the phase difference plate without compromising the alignment function.
2Duration of action of stationary object
If a phase difference plate uses materials with high light resistance, then the durability improves, but the optical characteristics may be compromised
Solution Approach 1:
The patent carefully adjusts the molecular structure parameters of the liquid crystal compound and the photo-alignment group to achieve the desired optical characteristics (biaxial phase difference with reciprocal wavelength dispersion) while selecting materials that inherently provide high light resistance and durability.
Solution Approach 2:
The composite material system allows simultaneous optimization of durability and optical characteristics by combining a photostable polymer matrix with a liquid crystal compound that provides the required optical properties, achieving both long-term stability and precise optical control.
3Adaptability or versatility
If a phase difference plate achieves biaxial phase difference with reciprocal wavelength dispersion, then the viewing angle characteristics improve, but the manufacturing process becomes more complex
Solution Approach 1:
The patent achieves biaxial phase difference with reciprocal wavelength dispersion by carefully selecting and combining specific liquid crystal compounds with defined molecular structures and optical properties. The parameter optimization of the liquid crystal compound enables the desired viewing angle characteristics while maintaining a relatively straightforward manufacturing process through solution casting and UV irradiation.
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 solution enhances the light resistance and maintains desired optical properties, specifically biaxial phase difference with reciprocal wavelength dispersion, even under high light emission intensity, thereby improving the durability and viewing angle characteristics of the antireflection film.
Implementation Method 1
a polymer having a repeating unit A including a photo-alignment group... in which the photo-alignment group includes a double bond structure of C═C or C═N
Implementation Method 2
a polymerizable liquid crystal compound having reciprocal wavelength dispersion... a composition containing a polymer having a repeating unit A including a photo-alignment group and a polymerizable liquid crystal compound
Implementation Method 3
biaxial phase difference with reciprocal wavelength dispersion... Re(450)≤Re(550)≤Re(650)
Data Source
AI summary
An object of the present invention is to provide a phase difference plate for an organic EL display device having excellent light resistance, an organic EL display device, and a method for producing a phase difference plate. The phase difference plate for an organic EL display device of an embodiment of the present invention has a phase difference layer formed from a composition containing a polymer having a repeating unit A including a photo-alignment group and a polymerizable liquid crystal compound having reciprocal wavelength dispersion, in which the photo-alignment group includes a double bond structure of C═C or C═N.