Phase difference film, circularly polarizing plate using same, and image display device

A technology of retardation film and retardation value, which is applied in the direction of polarizing elements, lighting devices, applications, etc., can solve the problems of unevenness, reduction, and non-elimination of difficulty in forming roll film stretching processing, etc. Small, less image quality degradation

Active Publication Date: 2014-09-24
MITSUBISHI RAYON CO LTD +1
View PDF14 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This patented technology allows for better performance at different temperatures over longer periods without losing its effectiveness or causing damage during use. It also reduces color changes that occur with prolonged exposure to heat and moist environments compared to existing films made from plastic materials. Overall this makes it suitable for various applications such as displays and other devices where images are displayed.

Problems solved by technology

The technical problem addressed in this patents relates to improving the performance of reflective elements like retroreflectors when exposed to different environmental conditions over time without losing their effectiveness caused by changing color balance between reflected colors. This issue arises because traditional polymers cannot withstand these varying temperatures and moisture levels while maintaining good transparency. Additionally, existing solutions require expensive processes involving complicated steps and lead to issues related to durability and stability under harsh usage scenarios.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Phase difference film, circularly polarizing plate using same, and image display device
  • Phase difference film, circularly polarizing plate using same, and image display device
  • Phase difference film, circularly polarizing plate using same, and image display device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0304] Hereinafter, although an Example demonstrates this invention in more detail, this invention is not limited to the following Example unless the summary is exceeded.

[0305] Hereinafter, the characteristic evaluation of polycarbonate resin, polycarbonate resin composition, roll film, and retardation film was performed by the following method. In addition, the characteristic evaluation method is not limited to the following method, Those skilled in the art can select suitably.

[0306] [Evaluation of polycarbonate resin and polycarbonate resin composition]

[0307] (1) Photoelastic coefficient

[0308]

[0309] Using a spacer with a width of 8cm, a length of 8cm, and a thickness of 0.5mm, vacuum-dry at 80°C for 5 hours with a hot press at a hot pressing temperature of 200-250°C, preheating for 1-3 minutes, and a pressure of 20MPa. 4.0 g of the polycarbonate resin sample was pressurized for 1 minute, then taken out together with the spacer, and pressurized and cooled a...

Synthetic example 1

[0364] 445.1 parts by weight of isosorbide (hereinafter, sometimes abbreviated as "ISB"), 906.2 parts by weight of 9,9-(4-(2-hydroxyethoxy)phenyl) fluorene (hereinafter, sometimes abbreviated as "BHEPF") 15.4 parts by weight of polyethylene glycol with a molecular weight of 1000 (hereinafter, sometimes abbreviated as "PEG#1000"), 1120.4 parts by weight of diphenyl carbonate (hereinafter, sometimes abbreviated as "DPC"), and cesium carbonate as a catalyst ( 0.2% by weight aqueous solution) 6.27 parts by weight are dropped into the reactor, under nitrogen atmosphere, as the operation of the first stage of reaction, make the heat medium temperature of reaction container be 150 ℃, make raw material dissolve while stirring as needed (about 15 minute). Next, the pressure in the reaction vessel was changed from normal pressure to 13.3 KPa, and the temperature of the heating medium in the reaction vessel was raised to 190° C. over 1 hour, while the generated phenol was extracted out o...

Synthetic example 2

[0367] In Synthesis Example 1, 489.7 parts by weight of ISB, 856 parts by weight of BHEPF, 16 parts by weight of PEG#1000, 1162.2 parts by weight of DPC, and 6.5 parts by weight of cesium carbonate aqueous solution as a catalyst were used. Synthesis example 1 was carried out similarly, and the polycarbonate resin B of BHEPF / ISB / PEG#1000=36.7 mol% / 63.0 mol% / 0.3 mol% was obtained.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Thicknessaaaaaaaaaa
Login to view more

Abstract

The purpose of the present invention is to provide a phase difference film which is not prone to color loss and color shift even in environments with harsh temperature conditions and humidity conditions, which can be manufactured by the melt film formation method. This phase difference film fulfills the relations of expressions (A) and (B) below. Expression (A): 0.7 < R1(450)/R1(550) < 1; Expression (B): |R2(450)/R2(550) - R1(450)/R1(550)| < 0.020

Description

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Owner MITSUBISHI RAYON CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products