Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Liquid crystal aligning agent and liquid crystal display device employing it

a liquid crystal display device and aligning agent technology, applied in the direction of instruments, transportation and packaging, chemistry apparatus and processes, etc., can solve the problems of display failure, difficult to satisfy all the required characteristics only with conventional techniques, and persistence of displayed images, etc., to achieve excellent liquid crystal alignment properties, reduce charge accumulation, and high voltage retention characteristics

Inactive Publication Date: 2009-09-03
NISSAN CHEM CORP
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0004]Under these circumstances, it is an object of the present invention to provide a liquid crystal aligning agent to provide a liquid crystal alignment film excellent in liquid crystal alignment properties, liquid crystal controlling power and rubbing resistance, having high voltage retention characteristics and having reduced charge accumulation, and a liquid crystal display device which hardly causes image failure, decrease in contrast, persistence of the image, etc.

Problems solved by technology

If the liquid crystal alignment film has low liquid crystal alignment properties, image failure may occur, and if the alignment controlling power of liquid crystal is low, the liquid crystal which has been continuously driven will not recover to the initial state, thus causing persistence of the displayed image.
If the rubbing resistance of the liquid crystal alignment film is low, the film may be separated or the film surface may be scraped away by rubbing, which may cause display failure.
However, characteristics required for a liquid crystal alignment film become strict along with an improvement in performance of liquid crystal display devices, and it becomes difficult to satisfy all the required characteristics only with conventional technique.

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
  • Liquid crystal aligning agent and liquid crystal display device employing it
  • Liquid crystal aligning agent and liquid crystal display device employing it
  • Liquid crystal aligning agent and liquid crystal display device employing it

Examples

Experimental program
Comparison scheme
Effect test

examples

Explanation of Abbreviations Used in the Present Examples

Tetracarboxylic Dianhydrides

[0087]TC−1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride[0088]TC−2: 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride[0089]TC−3: 1,2,3,4-butanetetracarboxylic dianhydride[0090]TC−4: bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride[0091]TC−5: pyromellitic dianhydride

Diamines

[0092]DA−1: 4,4′-diaminodiphenylamine[0093]DA−2: 3,6-diaminocarbazole[0094]DA−3: 4,4-diaminodiphenylmethane[0095]DA−4: 1,3-bis(4-aminophenoxy)benzene[0096]DA−5: di(4-aminophenyl)butane-1,4-dioate[0097]DA−6: 1,5-bis(4-aminophenoxy)pentane[0098]DA−7: 1,8-bis(4-aminophenoxy)octane[0099]DA−8: 1,5-bis[4-(4-aminophenoxy)phenoxy]pentane[0100]DA−9: 1,6-bis[4-(4-aminophenoxy)phenoxy]hexane[0101]DA−10: 4,4′-diamino-p-terphenyl[0102]DA−11: paraphenylenediamine[0103]DA−12: 4,4′-diaminodiphenyl ether[0104]DA−13: 1,3-diamino-4-octadecyloxybenzene

Organic Solvents

[0105]NMP: N-methyl-2-pyrrolidone[0106]GBL: γ-butyrolacto...

preparation examples

Preparation of Specific Polymer a

preparation example 1

[0108]18.73 g (0.094 mol) of TC−1 and 19.61 g (0.1 mol) of DA−1 were mixed in 345.1 g of NMP and reacted for 5 hours at room temperature to obtain a polyamic acid solution comprising TC−1 / DA−1. The polymerization reaction proceeded easily and uniformly, and the reduced viscosity of the obtained polyamic acid was 1.18 dl / g (at a concentration of 0.5 g / dl, in NMP at 30° C.). Further, this solution was diluted so that it comprised 5 wt % of the polyamic acid, 75 wt % of NMP and 20 wt % of BCS, to obtain a polyamic acid solution (PA−a1).

[0109]This polyamic acid solution (PA−a1) was spin-coated on a glass substrate provided with ITO transparent electrodes, dried for 5 minutes on a hotplate of 80° C. and then baked for 30 minutes in a hot air circulation oven at 220° C. to form a coated film having a thickness of 1 μm. Then, aluminum was deposited on the surface of the coated film to form an upper electrode (electrode area 0.0707 cm2). A voltage of 10 V was applied between the ITO electro...

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
volume resistivityaaaaaaaaaa
volume resistivityaaaaaaaaaa
volume resistivityaaaaaaaaaa
Login to View More

Abstract

To provide a liquid crystal aligning agent useful to obtain a liquid crystal alignment film excellent in liquid crystal alignment properties, alignment controlling power and rubbing resistance, having high voltage retention characteristics and having reduced charge accumulation, and a liquid crystal display device which is less susceptible to display failure, to lowering of contrast or to image persistence.A liquid crystal aligning agent comprising a low resistance polyimide precursor having a volume resistivity of from 1×1010 to 1×1014 Ωcm when formed into a film, and a high alignment polyimide precursor or polyimide having a specific structure, and a liquid crystal display device employing this liquid crystal aligning agent.

Description

TECHNICAL FIELD[0001]The present invention relates to a liquid crystal aligning agent to be used for forming a liquid crystal alignment film, and a liquid crystal display device employing it.BACKGROUND ART[0002]Liquid crystal display devices are presently widely used as display devices which can realize thin structure / light weight. The display characteristics of liquid crystal display devices are known to be substantially influenced by the alignment of liquid crystal, the pretilt angle of liquid crystal, the stability of the pretilt angle, electrical characteristics, etc. In order to improve the display characteristics of such liquid crystal display devices, not only the liquid crystal material to be used but also the liquid crystal alignment film which uniformly aligns the liquid crystal becomes important. If the liquid crystal alignment film has low liquid crystal alignment properties, image failure may occur, and if the alignment controlling power of liquid crystal is low, the li...

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
Patent Type & Authority Applications(United States)
IPC IPC(8): C09K19/04C08G73/10C09K19/56G02F1/1337
CPCC08G73/10Y10T428/1023G02F1/133723C09K19/56C09K2323/027C09K19/00G02F1/1337
Inventor TSUTSUI, KIMIAKISAKAI, TAKAHIROGOTO, KOHEI
Owner NISSAN CHEM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com