Cellulose-ester film, manufacturing method therefor, and polarizing plate

A technology of cellulose ester film and manufacturing method, which can be applied to polarizing elements, instruments, optical elements, etc., can solve the problems of reduced ductility of adhesive, increase in size, and no implied structure, etc., and achieve the effect of excellent adhesiveness

Active Publication Date: 2016-08-10
KONICA MINOLTA INC
View PDF25 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

) becomes larger, the ductility of the adhesive decreases, resulting in poor adhesion
In addition, when an ultraviolet curable adhesive is used as an adhesive, it is known that ultraviolet rays are usually irradiated from the side of the retardation film that does not contain an ultraviolet absorber. In the case of an absorbing compound, when the curing reaction is caused by ultraviolet radiation, the ultraviolet rays are absorbed by the compound and do not sufficiently reach the adhesive layer, resulting in poor adhesion due to uncured
[0009] In addition, it was found that in the manufacture of the DAC film, the retardation increasing agent is prone to produce tiny foreign matter or precipitates due to its compatibility with DAC, and these substances move on the film surface through stretching treatment, so that the contact of the above-mentioned film surface Greater deviation in corners, which hinders adhesion
[0010] A method for improving the variation in the contact angle of the film surface is disclosed in Patent Document 1, but the disclosed technology is to form a film by melt casting a composition containing cellulose acetate propionate and not containing a retardation increasing agent, It does not imply the composition of the invention and the solution to the technical problems of the present application

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
  • Cellulose-ester film, manufacturing method therefor, and polarizing plate
  • Cellulose-ester film, manufacturing method therefor, and polarizing plate
  • Cellulose-ester film, manufacturing method therefor, and polarizing plate

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0082] The film thickness of the above-mentioned cellulose ester film is within a range of 20 to 38 μm, which is a preferable film thickness range from the viewpoint of production of a thin film polarizing plate and contributing to thinning of a liquid crystal display device using the same.

[0083] From the viewpoint of optimizing the visibility of VA-mode liquid crystal display devices, the retardation value Re in the in-plane direction of the above-mentioned cellulose ester film is in the range of 45 to 60 nm, and the retardation value Rth in the film thickness direction is 110 to 140 nm. When it is within the range, it is a preferable range.

[0084] In addition, the above-mentioned retardation increasing agent is a nitrogen-containing heterocyclic compound containing a pyrazole ring or an imidazole ring having a structure represented by the above-mentioned general formula (A). Since the transmittance is adjusted to 80% or more, it is a preferable compound. Furthermore, t...

Synthetic example

[0210]

[0211] An example of synthesis of sugar esters that can be preferably used in the present invention is shown below.

[0212] [chemical formula 9]

[0213]

[0214] 34.2g (0.1 moles) of sucrose, 180.8g (0.8 moles) of benzoic anhydride, and 379.7g (4.8 moles) of pyridine are respectively loaded into the four-necked Erlenmeyer flask with stirring device, reflux cooler, thermometer and nitrogen inlet pipe, While bubbling nitrogen gas from a nitrogen gas introduction tube with stirring, it heated up, and esterification reaction was performed at 70 degreeC for 5 hours. Next, depressurize the Erlenmeyer flask to 4×10 2 Below Pa, after distilling off excess pyridine at 60° C., the inside of the Erlenmeyer flask was decompressed to below 1.3×10 Pa, and the temperature was raised to 120° C. to distill off most of benzoic anhydride and generated benzoic acid. Then, 1 L of toluene and 300 g of a 0.5 mass % sodium carbonate aqueous solution were added, and after stirring at...

Embodiment 1

[0521] Table 1 shows the contents of cellulose esters used in Examples. In the table, DAC means: diacetyl cellulose, CAP means: cellulose acetate propionate, and TAC means: triacetyl cellulose.

[0522] [Table 1]

[0523]

[0524]

[0525] [Preparation of Cellulose Ester Film 101]

[0526] The cellulose ester film 101 was prepared according to the method described below.

[0527] (Preparation of fine particle dispersion diluent)

[0528] After stirring and mixing 10 parts by mass of AEROSIL R812 (manufactured by Japan Aerosil Co., Ltd., primary average particle size: 7 nm, apparent specific gravity 50 g / L) and 90 parts by mass of ethanol with a dissolving bar for 30 minutes, use a Manton high-pressure disperser -Gaulin disperses to prepare a fine particle dispersion.

[0529] 88 parts by mass of dichloromethane was added to the obtained fine particle dispersion liquid while being stirred, and stirred and mixed with a dissolving bar for 30 minutes to dilute. The obtai...

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

No PUM Login to view more

Abstract

This invention addresses the problem of providing the following: a thin cellulose-ester film that performs well at producing a phase difference and adheres well to a polarizer via either a PVA-based liquid glue or a UV-curable adhesive; a method for manufacturing said cellulose-ester film; and a polarizing plate. Said cellulose-ester film, which contains, at least, cellulose acetate (resin A) having an acetyl-group substitution degree in the 2.1-2.6 range and a retardation-increasing agent, is characterized in that the contact angle between pure water and the surface of the cellulose-ester film is in the 30-75 degrees range, measuring said contact angle at 20 equally spaced points in the widthwise direction of the film yields a standard deviation in the 0.05-3.0 degrees range, and the transmittance of the cellulose-ester film at a wavelength of 320 nm is at least 80%.

Description

technical field [0001] The present invention relates to a cellulose ester film, a method for producing the same, and a polarizing plate. A cellulose ester film having excellent adhesiveness in both the glue and the ultraviolet curable adhesive, and excellent in phase difference development, a method for producing the same, and a polarizing plate. Background technique [0002] In recent years, due to the enlargement, thinning, and high-definition of liquid crystal display devices, wider polarizers, thinner films, and improved display quality are required. [0003] Conventionally, cellulose ester films have been used as protective films for polarizers. However, in terms of display quality such as widening, thinning, and contrast caused by retardation, the conventionally used cellulose triacetate film (also called cellulose triacetate film) TAC film) will cause problems when used directly as a retardation film. [0004] Originally, the TAC film has the property that retardati...

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
IPC IPC(8): G02B5/30B29C41/24B29C55/08C08J5/18C08K5/3445C08L1/12
CPCC08L1/12B29C41/28B29C55/12B29C55/14B29C55/16C08J5/18C08J2301/12G02B1/04G02B5/305C08L1/10
Inventor 铃木真一郎
Owner KONICA MINOLTA INC
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap