JPH09288213A - Elliptical polarization plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of a liquid crystal display when it is used outdoor and exposed to sun rays by using a cellulose film having specified or higher tensile strength as a protective film. SOLUTION: This elliptical polarization plate has a structure of protective film/polarizing film/protective film/(acryl) adhesive/protective film/phase difference film/protective film. A cellulose film having >=13kgf/mm<2> tensile strength is used for the protective films. The operation effect of the film is significant when the longitudinal dimensional change rate of the cellulose film at 100 deg.C for 100 hours is <=0.20% preferably 0.001 to 0.20%, and moreover, a much higher operation effect of the film can be obtd. when the longitudinal dimensional change rate of the cellulose film at 70 deg.C and 90% RH for 500 hours is <=0.50%, preferably 0.0001 to 0.50%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elliptically polarizing plate, and more particularly to an elliptically polarizing plate having excellent durability when exposed to sunlight and an elliptically polarizing plate provided with a functional layer.

[0002]

2. Description of the Related Art Conventionally, STN (Super Twi)
A high-contrast liquid crystal display that utilizes the birefringence of a steed Nematic) type liquid crystal is used in a personal computer, a word processor, or the like. Since such a liquid crystal display is based on the birefringence of the liquid crystal, the display is generally colored in blue to yellow. Therefore, measures have been taken to compensate for the phase difference due to the birefringence of the STN type liquid crystal, return the elliptically polarized light to the linearly polarized light and cancel the coloring. As a means therefor, a system using an elliptically polarizing plate composed of a polarizing plate and a retardation plate made of a birefringent film has been proposed. This method is called F-STN method, etc., which enables black and white display by a single layer cell,
The bulky and heavy weight problems of the D-STN method in which separate liquid crystal cells are stacked up to then have been solved.

This elliptically polarizing plate is obtained by laminating a polarizing plate (protective film / polarizing film / protective film) and a retardation film (protective film / retardation film / protective film) as described above. Specifically, it is adhered using an adhesive so that the optical axis of the polarizing plate and the optical axis of the retardation plate have a predetermined angle, and a film such as cellulose triacetate is used as the protective film. Is there.

[0004]

However, recently, the liquid crystal display using the above elliptical polarizing plate is often used outdoors, and it is desired to improve the durability performance when exposed to sunlight. .

[0005]

In view of the above situation, the present inventor has proposed an ellipse composed of protective film / polarizing film / protective film / (acrylic) adhesive / protective film / retardation film / protective film. In the polarizing plate, by using a cellulose-based film having a tensile strength of 13 kgf / mm ² or more as a protective film, the above durability performance is sufficiently satisfied, and even when various functional layers are laminated, the function is sufficiently exhibited. As a result, the present invention has been completed.

In the present invention, the rate of dimensional change in the machine direction (MD) of the cellulosic film at 100 ° C. for 100 hours is 0.20% or less (preferably 0.00).
When it is 1 to 0.20%), the effect of the present invention can be remarkably obtained.
The dimensional change rate in the longitudinal (MD) direction at 0 ° C., 90% RH and 500 hours is 0.50% or less (preferably 0.000).
When it is 1 to 0.50%), further action and effect can be obtained. The longitudinal direction means the longitudinal direction of the film at the time of manufacturing the cellulosic film, that is, MD (machine).
direction), and the dimensional change rate (%) is [(1
Length after treatment at 00 ° C for 100 hours-length before treatment) /
(Length before processing)] × 100.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
Examples of the polarizing film used in the present invention include a polyvinyl alcohol-based film, an ethylene vinyl alcohol-based film, a cellulose-based film, and a polycarbonate-based film, and a polarizing film of a polyvinyl alcohol-based resin is preferable in terms of processability and the like. The film will be described below, but the present invention is not limited to the film.

The polyvinyl alcohol-based resin is usually produced by saponifying polyvinyl acetate obtained by polymerizing vinyl acetate. However, the present invention is not limited to this, and a small amount of unsaturated carboxylic acid is used. (Including salts, esters, amides, nitriles, etc.), olefins, vinyl ethers, unsaturated sulfonates and the like, and may contain a component copolymerizable with vinyl acetate. Further, polyvinyl butyral resin obtained by reacting a polyvinyl alcohol-based resin with aldehydes in the presence of an acid, a so-called polyvinyl acetal resin such as a polyvinyl formal resin, and other polyvinyl alcohol-based resin derivatives are also exemplified, but are not limited thereto. Absent. Among these, polyvinyl alcohol (based resin) having a high degree of saponification and a high degree of polymerization is preferred from the viewpoint of good heat resistance.
That is, the degree of saponification is preferably 95 mol% or more, and further 9
9 mol% or more, particularly 99.5 mol% or more,
The (average) degree of polymerization is preferably 1000 or more, more preferably 10
00-6000, especially 1500-5000, especially 250
Those of 0 to 4000 are preferable.

As a method for producing a polarizing film using the polyvinyl alcohol resin, a stock solution obtained by dissolving the polyvinyl alcohol resin in water or an organic solvent is cast to form a film.
A method of stretching and dyeing with iodine, performing stretching and dyeing at the same time, or performing iodine dyeing and stretching, and then treating with a boron compound may be used. The polarizing film thus obtained, like the retardation film described below, is provided with a protective film excellent in optical transparency and mechanical strength on both sides thereof via an adhesive, but in the present invention. Has a tensile strength of 13 kgf / mm ² or more (preferably 13 to 50 kgf / mm ² , and further 14
˜40 kgf / mm ² ) cellulosic film is used, and the conventional tensile strength is 13%.
A film of less than kgf / mm ² cannot achieve the object of the present invention. The tensile strength is ASTM
It is a value measured according to -D638.

In the present invention, the rate of dimensional change in the longitudinal (MD) direction of the cellulosic film at 100 ° C. for 100 hours is 0.20% or less (preferably 0.001 to 0.001).
0.20%, more preferably 0.001 to 0.15%), and further 70% of the cellulose-based film.
The rate of dimensional change in the longitudinal (MD) direction at 500 ° C. and 90% RH for 0.5 hours is 0.50% or less (preferably 0.0001).
.About.0.50%, more preferably 0.0001 to 0.40%). 100 of the cellulosic film
When the dimensional change rate in the longitudinal (MD) direction at 100 ° C for 100 hours exceeds 0.20%, or at 70 ° C, 90% RH, 500
The rate of dimensional change in the machine direction (MD) over time is 0.50%
If it exceeds the range, the display quality when used in a liquid crystal panel or the like is inferior, which is not preferable.

In order to obtain such a cellulosic film, the content of the plasticizer may be adjusted during the production of the film,
Examples of the method include heat treatment after film formation, but the method is not limited thereto. Specific examples of such a cellulose-based film include "Fujitac FT-UVDE".
80 "(manufactured by Fuji Photo Film Co., Ltd.) and the like. The cellulose ester as a raw material of the cellulose-based film is an ester of cellulose and a fatty acid, and examples thereof include cellulose diacetate, cellulose triacetate, cellulose tripropionate, and cellulose tributyrate, and these are used alone or in combination. To be done. Among these, cellulose triacetate (cellulose triacetate) is preferably used. The thickness of the cellulose-based film is not particularly limited, but is 50 to 150 μm.
Is preferable, and 70 to 120 μm is more preferable.

Regarding the lamination of the polarizing film and the cellulosic film, the main component is natural or synthetic rubber, acrylic resin, butyral resin, epoxy resin, polyester resin, polyamide resin, polyvinyl alcohol resin and the like. Using an adhesive or adhesive,
It can be adhered by an air drying method, a chemical curing method, a heat curing method, a heat melting method or the like. Further, as the retardation film used in the present invention, polyvinyl alcohol resin, ethylene-vinyl alcohol copolymer, polyvinyl chloride resin, polymethylmethacrylate resin, polycarbonate resin, polystyrene resin, polyester resin, Examples include molecularly oriented films made of polymers such as cellulose-based resins, polyarylate-based resins, polysulfone-based resins, and polyethersulfone-based resins, but polyvinyl alcohol similar to the above polarizing film in terms of processability and the like. A resin is preferably used.

The retardation film is obtained by uniaxially stretching a polyvinyl alcohol-based resin original film formed in the same manner as the above polarizing film to about 1.01 to 4 times. The film thus obtained has a thickness of 30 to 10
It has a retardation value of 10 to 700 nm in terms of physical properties.
It is a degree.

The retardation film thus obtained is provided with the above-mentioned specific cellulose film as a protective film on both sides thereof with an adhesive or the like in the same manner as the above-mentioned polarizing film. The thus-obtained polarizing plate (protective film / polarizing plate / protective film) and retardation plate (protective film / retardation film) are laminated via an adhesive to form the elliptically polarizing plate of the present invention. However, the pressure-sensitive adhesive is not particularly limited, and an acrylic pressure-sensitive adhesive, a silicon-based pressure-sensitive adhesive or the like can be used.
It is preferable to use an acrylic pressure-sensitive adhesive in terms of optical characteristics and durability characteristics.

As such an acrylic pressure-sensitive adhesive, a known one is used, and as a constituent component of the acrylic resin which is a main component of the acrylic pressure-sensitive adhesive, a soft main monomer component having a low glass transition temperature or a glass transition temperature is used. A high and hard comonomer component, and if necessary, a small amount of a functional group-containing monomer component.

Specifically, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-acrylic acid acrylate
Ethylhexyl, lauryl acrylate, benzyl acrylate, alkyl acrylates having about 2 to 12 carbon atoms of alkyl groups such as cyclohexyl acrylate, n-butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, Benzyl methacrylate, a main monomer component such as alkyl methacrylate having about 4 to 12 carbon atoms of an alkyl group such as cyclohexyl methacrylate, and the comonomer component include methyl acrylate, methyl methacrylate, ethyl methacrylate, Examples thereof include alkyl methacrylates having 1 to 3 carbon atoms such as propyl methacrylate, vinyl acetate, acrylonitrile, methacrylonitrile, and styrene.

In addition to the above, the functional group-containing monomer component is a monocarboxylic acid such as acrylic acid, methacrylic acid or crotonic acid, a polyvalent carboxylic acid such as maleic acid, fumaric acid, citraconic acid, glutaconic acid or itaconic acid, and Carboxyl group-containing monomers such as anhydrides, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-chloro-2-hydroxylpropyl (meth) acrylate, diethylene glycol mono (meth) acrylate, and the like. In addition to hydroxyl group-containing monomers such as N-methylolacrylamide, (meth) acrylamide, dimethylaminoethyl methacrylate, glycidyl methacrylate, allyl glycidyl ether and the like can be mentioned.

Among the functional group-containing monomer components,
Particularly, use of a carboxyl group-containing monomer is preferred. Although the content of such a main monomer component cannot be unconditionally defined by the type or content of a comonomer component or a functional group-containing monomer component to be contained, it is generally preferable to contain the main monomer in an amount of 50% by weight or more. . The acrylic resin of the present invention is easily produced by a method well known to those skilled in the art, such as radical copolymerization of a main monomer, a comonomer, and, if necessary, a functional group-containing monomer in an organic solvent.

The organic solvent used for the above polymerization is
Aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as n-propyl alcohol and isopropyl alcohol; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone. . Specific examples of the polymerization catalyst used in the radical polymerization include azobisisobutyronitrile, benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide and the like, which are ordinary radical polymerization catalysts.

The above acrylic resin is mixed with additives such as a cross-linking agent and a coupling agent (silicone, aluminum, titanium) in an amount of 0.001 to 5% by weight, if necessary, and finally used for a glass substrate. It becomes the acrylic adhesive. Examples of the crosslinking agent include isocyanate compounds, epoxy compounds, aldehyde compounds, amine compounds, metal salts, metal alkoxides, metal chelate compounds, ammonium salts, and hydrazine compounds. The amount of the crosslinking agent is 0.0% with respect to 100 parts by weight of the acrylic resin.
It is about 01 to 8 parts by weight. If necessary, a coupling aid (adhesion imparting) aid or a crosslinking aid (epoxy compound, amine compound, or the like) may be used.

The surface of the retardation plate of the elliptically polarizing plate is adhered to a substrate such as a glass plate using the acrylic adhesive as described above, and is used for the purpose as described below.
In the present invention, in order to enhance various functions of the elliptically polarizing plate,
It is also useful to further laminate a functional layer on the outer surface of the protective film provided on the polarizing plate of the elliptically polarizing plate to obtain an elliptically polarizing plate with a functional layer.

Specific examples of such a functional layer include an anti-glare layer, a hard coat layer, an anti-reflection layer,
Examples include a half-reflection layer, a reflection layer, a luminous layer, and an electroluminescence layer. Further, a combination of two or more types may be used. For example, a luminous layer and a reflective layer, a luminous layer and a half-reflection layer, a luminous layer and a light Examples include a combination of a diffusion layer, a light storage layer and an electroluminescence layer, a half reflection layer and an electroluminescence layer, and an antiglare layer and an antireflection layer. However, it is not limited to these.

The anti-glare layer is for diffusing a reflected image of a fluorescent lamp or the like on the surface of the polarizing plate to make it easy to see the display, and for preventing the adhesion of fingerprints or the like. Melamine-based resin containing an inorganic filler such as silica beads of 1 to 20 μm or an organic filler such as acrylic, styrene, divinylbenzene, melamine or benzoguanamine,
Urethane resin, acrylic resin, alkyd resin,
A thermosetting resin such as a silicone resin or an energy ray curable resin such as a polyfunctional acrylic ultraviolet ray or an electron beam is used, and a bar coat,
Coating is performed by a known coating method such as roll coating, gravure coating, and air knife coating. The thickness of the antiglare layer is about 1 to 20 μm.

The hard coat layer has a surface hardness of H (pencil hardness) or more to impart scratch resistance, and specifically includes a melamine resin, a urethane resin, an acrylic resin,
A thermosetting resin such as an alkyd resin, a silicone resin, or a polyfunctional acrylic resin is used as a main component, and an energy ray-curable resin such as an ultraviolet ray or an electron beam or a metal oxide such as SiO ₂ is used. Formed on the film surface. As a method for forming the layer, known coating methods such as bar coating, roll coating, gravure coating, and air knife coating are preferably used in the case of a resin, and a vacuum evaporation method is preferably used in the case of a metal oxide. . The thickness of the hard coat layer is about 0.1 to 20 μm.

The anti-reflection layer is for suppressing the reflection of external light on the surface of the polarizing plate and making the display easier to see, and specifically, it is a fluorine resin, SiO ₂ , MgF ₂ , Zr.
Metal oxides such as O ₂ , AlO ₃ and TiO ₂ are used,
It is formed on the surface of a cellulosic film. As a method for forming the layer, a known coating method such as bar coating, roll coating, gravure coating, or air knife coating is used in the case of a resin, and a vacuum deposition method is preferably used in the case of a metal oxide. The metal oxide is often laminated in two or more layers, and the thickness of the anti-reflection layer is 0.01 to 1 μm.
m. It is also effective to use a combination of an anti-reflection layer and an anti-glare layer.

The half reflection layer is for utilizing external light reflection in the daytime and for utilizing the transmitted light from the backlight at night to display a display to achieve low power consumption. , Flake mica, titanium dioxide-coated mica, plate-shaped fish scale foil, hexagonal plate-like basic lead carbonate, fine mica or pearl pigments such as bismuth acid chloride, fine glass beads, glass products such as crushed glass particles, plastic chips, plastic A synthetic resin layer having optical transparency such as (meth) acrylic resin, acetate, polycarbonate, polyester, polyurethane, etc. is prepared by using an adhesive containing transparent and / or translucent particles such as crushed particles of plastic products. It is attached to a polarizing plate, or a film having the transparent and / or semitransparent particles coated on the synthetic resin layer is attached to the polarizing plate via an adhesive. Ri a method such as to adjust them is taken, the present invention is not limited to this. The elliptically polarizing plate with a half reflection layer is practically used as a lower polarizing plate of a liquid crystal panel, so that the half reflection layer serves as a lower layer, that is, the cellulosic film surface on which the half reflection layer is not provided is a liquid crystal panel. It is pasted.

The reflection layer is used to display a display by utilizing the reflection of external light in the daytime and to omit the backlight. Specifically, a cellulose acetate film such as a cellulose triacetate film or polyethylene terephthalate ( A metal such as aluminum or silver having a high reflectance is vapor-deposited on a substrate such as PET), which is attached to a polarizing plate (one cellulose-based film) via an adhesive. The elliptically polarizing plate with a reflective layer is practically used as the lower polarizing plate of a liquid crystal panel, and the other cellulose-based film surface without the reflective layer is attached to the liquid crystal panel so that the reflective layer is the lower layer. Or an organic white light diffusion film is attached in some cases.

The luminous layer is for accumulating outside light in the daytime so that a display can be displayed without a backlight at night. Specifically, zinc sulfide or calcium sulfide is used as a matrix, Copper is added as an activator to this, and a green phosphor that is mixed with a flux and fired is often used, or the phosphorescent coating contains an element that emits α-rays such as radium and strontium, and β-rays. It is used as a light-emitting paint that emits a small amount of light by itself. The phosphorescent layer is coated on one side (one cellulose film) of the polarizing plate with a binder resin such as an acrylic resin, and the elliptical polarizing plate with the phosphorescent layer is practically used as a lower polarizing plate of a liquid crystal panel. Is a lower layer, that is, the other cellulose-based film surface not provided with the phosphorescent layer is bonded to the liquid crystal panel. It is also effective to provide a reflective layer below the luminous layer or to provide a half-reflection layer between the luminous layer and the polarizing plate.

The electroluminescent layer is intended to reduce the weight and thickness of the backlight instead of the conventional backlight, and is practically provided on the lower layer of the lower polarizing plate of the liquid crystal panel. As an electroluminescent material,
There are an inorganic material and an organic material, and the inorganic material includes phosphor particles such as zinc sulfide, and the organic material is tris (8-quinolinolato) aluminum complex.
Bis (benzoquinolinolato) beryllium complex and the like can be mentioned. In actual use, an ITO electrode is provided on one side (the polarizing plate side) of the electroluminescent layer, and a dielectric layer and a back electrode are provided on the other side, and current is passed through the ITO electrode and the back electrode to emit light. It is also effective to provide a light storage layer or a half reflection layer between the electroluminescence layer and the polarizing plate.

In the present invention, the above-mentioned various functional layers are provided on the elliptical polarizing plate, and the various functional layers are provided on the elliptic polarizing plate in various combinations as described above, whereby the functions of the various functional layers are sufficiently exhibited. In addition, it exhibits an excellent durability effect when exposed to sunlight. Furthermore, in the elliptically polarizing plate with a functional layer of the present invention, the above acrylic pressure-sensitive adhesive layer is further provided on the surface (retardation plate side) on which the functional layer is not provided, so that it can be used as a glass substrate for a liquid crystal display device or the like. It is often attached and used for mounting.

Thus, the elliptically polarizing plate of the present invention has excellent elliptically polarizing properties and can be laminated with various functional layers, has excellent durability when exposed to sunlight, and exhibits the functions of various functional layers sufficiently. , Electronic desk calculator, electronic clock, word processor,
Liquid crystal display devices such as measuring instruments for automobiles and machinery, sunglasses, eyeglasses, stereoscopic glasses, display elements (CRT, LC)
D) and the like, it is used for a reflection reducing layer, medical equipment, building materials, toys, etc., and is particularly useful for liquid crystal display devices such as measuring instruments for automobiles and machines.

[0032]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. In the examples, "part" and "%" are based on weight unless otherwise specified. Example 1 A polyvinyl alcohol-based polarizing film having a thickness of 25 μm (average degree of polymerization: 3500, average degree of saponification: 99.5 mol%,
Polyvinyl alcohol adhesive (3
% Aqueous solution, dry coating thickness 0.01 μm) as a cellulosic film “FUJITAC FT-UVDE8”.
0 "(manufactured by Fuji Photo Film Co., Ltd., cellulose triacetate film, tensile strength 16.5 kgf / mm ² , 80 μm thickness, 100 ° C. × 100 hours longitudinal (MD) dimensional change rate 0.06%, 70 After sticking the dimensional change rate in the longitudinal (MD) direction of 0.20% at ℃ × 90% RH × 500 hours, 10
After drying at 0 ° C. for 1 minute, a polarizing plate was obtained. On the other hand, film thickness 75
“Fujitac FT-UVDE80” (same as above) on both sides of the polyvinyl alcohol retardation film (average degree of polymerization 3500, average degree of saponification 99.8 mol%, stretched 1.12 times, R value 390 nm) of μ in the same manner as above. ) Was attached to obtain a retardation plate. Next, the above-mentioned polarizing plate and retardation plate were attached using an acrylic pressure-sensitive adhesive (dry thickness 25 μm) to obtain an elliptically polarizing plate of the present invention.

Using the retardation plate thus obtained, the Rd ₀ value before exposure to sunlight and the Rd ₁ value after 200 hours exposure to sunlight were measured using a polarizing microscope equipped with a Babinet-type compensator (Nikon POH-
1 type), the change rate ΔRd was calculated by the following formula, and the durability was evaluated as follows. Change rate ΔRd = | Rd ₀ value−Rd ₁ value | / Rd ₀ value The above Rd ₀ value and Rd ₁ value mean the retardation value, and the main stretching direction of the retardation plate (retardation film). It is defined by the product of the refractive index difference (II _MD- II _TD ) in the (MD direction) and the direction (TD direction) perpendicular thereto and the thickness (d) of the retardation film. Evaluation criteria ○ --- ΔRd <0.18 × --- ΔRd ≧ 0.18

Example 2 An ellipse was prepared in the same manner as in Example 1 except that polyvinyl alcohol having an average polymerization degree of 2600 and an average saponification degree of 99.5 mol% was used for the polarizing film and the retardation film. A polarizing plate was obtained and evaluated in the same manner.

Example 3 An ellipse was prepared in the same manner as in Example 1 except that polyvinyl alcohol having an average polymerization degree of 1700 and an average saponification degree of 99.5 mol% was used for the polarizing film and the retardation film. A polarizing plate was obtained and evaluated in the same manner.

Comparative Example 1 In Example 1, as the cellulosic film, "Fujitac FT-UV80" (manufactured by Fuji Photo Film Co., Ltd.,
Cellulose triacetate film, tensile strength 12.6kgf
/ Mm ² , 80 μm thickness, 100 ° C x 100 hours vertical (MD) dimensional change rate 0.40%, 70 ° C x 90%
Dimension change rate in the machine direction (MD) of RH x 500 hours 0.6
(7%) was used to obtain an elliptically polarizing plate in the same manner as in Example 1, and the same evaluation was performed. Table 1 shows the test results of the above Examples and Comparative Examples.

[Table 1]

Example 4 A functional layer as shown in Table 2 was provided on one surface of the retardation plate obtained in Example 1, and the functional evaluation of the retardation plate with various functional layers was evaluated by the following method. . (Anti-glare layer) Diffusivity of fluorescent lamp The display quality of the image when the fluorescent lamp was transferred to the retardation plate was evaluated according to the following criteria. A: The shape of the fluorescent lamp could not be recognized B: The shape of the fluorescent lamp could be recognized Change in haze value The haze value before and after leaving the retardation plate under the above conditions was measured and evaluated according to the following criteria. .・ ・ ・: Change rate of haze value before and after leaving less than 30% ×: Change rate of haze value before and after leaving is 30% or more

(Hard Coat Layer) Scratch Resistance The presence or absence of scratches when the surface of the retardation plate was rubbed with steel wool 10 times at 1 kg / cm ² was measured and evaluated according to the following criteria.・ ・ ・: No scratches x: scratches Surface pencil hardness The surface hardness of the retardation plate was measured according to JIS K 5400, and evaluated according to the following criteria. ○ ・ ・ ・ having surface hardness of H or more × ・ ・ ・ having surface hardness of less than H

(Anti-Reflection Layer) Reflection of Fluorescent Lamp The display quality of the image when a fluorescent lamp was projected on the retardation plate was evaluated according to the following criteria. A: Other display is not hindered by the reflection of the fluorescent lamp B: Other display is hindered by the reflection of the fluorescent lamp Surface reflectivity Reflection before and after leaving the retardation plate under the above conditions The rate was measured and evaluated according to the following criteria. ○ ・ ・ ・ Change rate of reflectance before and after leaving is less than 30% × ・ ・ ・ Change rate of reflectance before and after leaving is 30% or more

(Half Reflection Layer) Actual Display Quality at Night and Day The display of the retardation plate was evaluated at night and day according to the following criteria. A: The notation can be recognized in a short time both at night and during the day. B: The notation cannot be recognized within a short time at night and during the day. Transmittance The transmittance before and after leaving the retardation plate under the above conditions was measured. Was evaluated according to the following criteria.・ ・ ・: Change rate of transmittance before and after leaving less than 30% ×: Change rate of transmittance before and after leaving is 30% or more Reflectivity The reflectance before and after leaving the retardation plate under the above conditions is It was measured and evaluated according to the following criteria. ○ ・ ・ ・ Change rate of reflectance before and after leaving is less than 30% × ・ ・ ・ Change rate of reflectance before and after leaving is 30% or more

(Reflective layer) Actual display quality during the day The display of the retardation plate during the day was evaluated according to the following criteria. A: Notation could be recognized in a short time B: Notation could not be recognized in a short time Reflectivity The reflectance before and after the retardation plate was left under the above conditions was measured and evaluated according to the following criteria. ○ ・ ・ ・ Change rate of reflectance before and after leaving is less than 30% × ・ ・ ・ Change rate of reflectance before and after leaving is 30% or more

(Luminescent Layer) Actual Display Quality at Night The display of the retardation plate at night was evaluated according to the following criteria. A: the notation is recognizable B: the notation is not recognizable Surface luminance The luminance before and after the retardation plate is left under the above conditions is measured,
Evaluation was made according to the following criteria.・ ・ ・: Change rate of luminance before and after leaving less than 30% ×: Change rate of luminance before and after leaving is 30% or more

(Electroluminescence Layer) Actual Display Quality at Night The display of the retardation plate at night was evaluated according to the following criteria. A: Notation is recognizable in a short time B: Notation is not recognizable in a short time Surface luminance
Evaluation was made according to the following criteria.・ ・ ・: Change rate of luminance before and after leaving less than 30% ×: Change rate of luminance before and after leaving is 30% or more

[0044]

[Table 2] Functional layer Constitution of functional layer Film thickness (μ) Example 4 (1) AG layer Coated with 1% of silica filler having a particle size of 3 μm in acrylic resin coated (2) HC layer acrylic resin Coat 1 (3) AR layer Coated with fluorine resin 0.1 (4) HR layer Coated with 10% 10% titanium dioxide-coated mica in acrylic resin (5) GR layer PET film was vapor-deposited with silver 1 layer of film (6) Luminescent layer Coated with acryl resin containing 5% of zinc sulfide and 5% of copper 5 phosphorescent material coated (7) EL layer Bis (benzoquinolinolite 5) in acrylic resin coated on PE T film obtained by blending a beryllium 5%, further laminated one which formed transparency electrode of ITO Note) AG layer: anti-glare layer, HC layer: hard coat layer, AR layer Antireflection layer, HR layer: Half reflection layer, GR layer: reflective layer, EL layers: an electroluminescent layer, PET: polyethylene terephthalate

Example 5 Using the retardation plate obtained in Example 2, a functional layer was provided in the same manner as in Example 4, and the same evaluation as in Example 4 was carried out.

Example 6 Using the retardation plate obtained in Example 3, a functional layer was provided in the same manner as in Example 4, and the same evaluation as in Example 4 was carried out. Example 4
Table 3 shows the evaluation results of ~ 6.

[0047]

[Table 3] Note) In the table, the evaluation of the functional layer ~
Show.

[0048]

Since the elliptically polarizing plate of the present invention is laminated with a specific cellulose-based film, it has excellent elliptically polarized light characteristics and excellent durability when exposed to sunlight, and various functional layers are laminated. Even if it fully demonstrates its function, it can be used for electronic desk calculators, electronic clocks, word processors, liquid crystal display devices such as instruments for automobiles and machinery, sunglasses, eye protection glasses, stereoscopic glasses,
It is used for a reflection reducing layer for a display element (CRT, LCD, etc.) and is particularly useful for liquid crystal display devices such as measuring instruments for automobiles and machines.

Claims (20)

[Claims] 1. An elliptical polarizing plate comprising a protective film / polarizing film / protective film / adhesive / protective film / retardation film / protective film, having a tensile strength of 13 k.
An elliptically polarizing plate using a cellulose-based film having a gf / mm ² or more as a protective film. 2. A cellulose film at 100 ° C., 10
The rate of dimensional change in the machine direction (MD) at 0 hours is 0.20
% Or less, The elliptically polarizing plate according to claim 1, wherein 3. A cellulosic film at 70 ° C. and 90%
The elliptically polarizing plate according to claim 1 or 2, wherein a dimensional change rate in a longitudinal (MD) direction at RH of 500 hours is 0.50% or less. 4. The elliptically polarizing plate according to claim 1, wherein a polyvinyl alcohol film having an average degree of polymerization of 1000 to 6000 is used as the polarizing film and the retardation film. 5. The elliptically polarizing plate according to claim 1, wherein a polyvinyl alcohol film having an average degree of polymerization of 1500 to 5000 is used as the polarizing film and the retardation film. 6. The elliptically polarizing plate according to claim 1, wherein a polyvinyl alcohol film having an average degree of polymerization of 2500 to 4000 is used as the polarizing film and the retardation film. 7. The elliptically polarizing plate according to claim 1, wherein a functional layer is provided on the outside of the cellulosic film. 8. The elliptically polarizing plate according to claim 7, wherein the functional layer is an antiglare layer. 9. The elliptically polarizing plate according to claim 7, wherein the functional layer is a hard coat layer. 10. The elliptically polarizing plate according to claim 7, wherein the functional layer is an anti-reflection layer. 11. The elliptically polarizing plate according to claim 7, wherein the functional layer is a half reflection layer. 12. The elliptically polarizing plate according to claim 7, wherein the functional layer is a reflective layer. 13. The elliptically polarizing plate according to claim 7, wherein the functional layer is a light storage layer. 14. The elliptically polarizing plate according to claim 7, wherein the functional layer is an electroluminescence layer. 15. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises an anti-glare layer and an anti-reflection layer. 16. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises a light storing layer and a reflecting layer. 17. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises a light storage layer and a half reflection layer. 18. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises a light storage layer and a light diffusion layer. 19. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises a light storage layer and an electroluminescence layer. 20. The elliptically polarizing plate according to claim 7, wherein the functional layer comprises a half reflection layer and an electroluminescence layer.