KR101397301B1 - Elliptical polarizing plate, method for producing elliptical polarizing plate, liquid crystal display, and electroluminescent display - Google Patents

Abstract

A elliptically polarizing plate which does not cause problems such as peeling even under high temperature and high humidity conditions by simplifying the layer structure of the elliptically polarizing plate is an elliptically polarizing plate in which a translucent protective film, a polarizing element and an optically anisotropic element are laminated in this order, There is provided an elliptically polarizing plate characterized in that an anisotropic element comprises at least a liquid crystal composition having twisted nematic or hybrid nematic orientation in a liquid crystal state and exhibiting unilamellarity and fixing the orientation.

An elliptically polarizing plate, a liquid crystal display, a twisted nematic, a hybrid nematic, an electroluminescent display

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elliptically polarizing plate, an elliptically polarizing plate, a method of manufacturing an elliptically polarizing plate, a liquid crystal display, and an electroluminescent display device using the ELLIPTICAL POLARIZING PLATE, LIQUID CRYSTAL DISPLAY, AND ELECTROLUMINESCENT DISPLAY,

The present invention relates to an elliptically polarizing plate composed of an optically anisotropic element having a liquid crystal layer in which a twisted nematic alignment structure or a hybrid nematic alignment structure is immobilized, and a method for manufacturing the same. The present invention also relates to a liquid crystal display device and an electroluminescent display device using the elliptically polarizing plate.

The liquid crystal display device is largely classified into a transmissive type capable of displaying an image in a transmissive mode, a reflective type capable of displaying an image in a reflective mode, and a transflective type capable of displaying an image in both a transmissive mode and a reflective mode, And light weight, it is widely used as a display device for a notebook computer, a television, and the like. Particularly, a transflective liquid crystal display device adopts a display system having both a reflection type and a transmissive type, and is replaced with a display system in accordance with the brightness of the surroundings, so that it is possible to perform clear display in a spot or a cow while reducing power consumption Therefore, it is widely used in various portable electronic devices.

For example, in a STN type liquid crystal display device, a complete monochrome display is not achieved. In a TN type liquid crystal display device, in a transmissive mode, a liquid crystal molecule has a refractive index anisotropy due to its refractive index anisotropy, A liquid crystal display device having excellent display performance such as a problem that a viewing angle problem such as decrease in display contrast, change in display color, or inversion of grayscale in view can not be avoided in view of such a situation.

Means for improving the display performance of the STN-type liquid crystal display device have been proposed to some extent, but one of them is a method of arranging the retardation film between the polarizing plate and the liquid crystal cell of the liquid crystal display device. This method is advantageous in that it can be easily carried out without significantly changing the manufacturing process of the liquid crystal display device, except that the retardation film is joined to the polarizing plate to form an elliptically polarizing plate. However, when the thickness of the point-adhesive layer for bonding the retardation film and the polarizing plate increases and the film is wound on a roll in the manufacturing process of the elliptically polarizing plate, the amount of winding per roll is decreased, There is a problem that the thickness of the panel increases.

Further, since the layers are composed of different kinds of layers, the stretching and shrinking behavior of the respective layers with respect to heat or humidity is different, so that the interface between the polarizing plate and the retardation film is sometimes peeled off in various reliability tests. Conventionally, as a retardation film, a polymer film in which a polycarbonate or the like is uniaxially stretched and oriented is used in most cases. In the elongated film form, the orientation axis of the film is usually limited to the stretching direction, that is, the MD direction. Therefore, when an elliptically polarizing plate is produced by continuously joining a polarizing plate and a retardation film in the form of a elongate film, the specific case where the absorption axis of the polarizing plate and the orientation axis of the retardation film are parallel is limited. It is necessary to cut and bond the elongated film from the elongate film to form a non-parallel axial arrangement, thereby complicating the process and deteriorating the productivity. Further, it is difficult to freely control the orientation of the polymer in the stretched oriented retardation film, and there is a limitation in the degree of freedom of optical characteristics. As described above, the absorption axis of the polarizing plate and the orientation axis of the retardation film have various axial arrangements, and thus can not sufficiently cope with the demand for an elliptically polarizing plate having excellent optical performance.

On the other hand, in the retardation film using a liquid crystal compound, there has been proposed an optical anisotropic element in which the restrictions on the orientation axis are reduced, for example, a liquid crystal polymer is orientation-fixed (Patent Documents 1 and 2). Further, a 1/4 wavelength plate composed of a liquid crystal film in which a twisted nematic alignment structure is immobilized has been proposed (Patent Documents 3 and 4).

In the case of using such a liquid crystalline polymer, since the orientation axis angle can be arbitrarily set, it is possible to produce a plurality of elliptically polarizing plates by continuously joining from the elongated film form. However, as described above, the thickness of the elliptically polarizing plate is increased, and the interface between the polarizing plate and the optical anisotropic element may have problems such as peeling under high temperature or high humidity conditions.

As a method for solving the viewing angle characteristics of the TN type liquid crystal display device, a proposal of arranging an optical compensation film between the liquid crystal cell and the upper and lower polarizing plates in the conventional TN type liquid crystal display device using a twist angle of 90 degrees And has been practically used.

For example, an optical compensation film in which a discotic liquid crystal is hybrid-aligned is disposed between a liquid crystal cell and a vertical polarizer, and an optical compensation film in which a liquid crystalline polymer is hybrid nematically aligned is disposed between a liquid crystal cell and a vertical polarizer (Patent Documents 5 to 7).

Further, in the transflective liquid crystal display device, it is necessary to dispose the circular polarizing plate composed of one or more uniaxial retardation films and a polarizing plate on the upper and lower sides of the liquid crystal cell in the display mode in the transmission mode.

This transflective liquid crystal display device has proposed a method using an optical compensation film in which a circularly polarizing plate disposed between a liquid crystal cell and a backlight is oriented in a nematic hybrid orientation in magnifying a viewing angle of a transmission mode (Patent Document 8).

As an aspect of high-performance optical characteristics, similarly to the STN type liquid crystal display device, there is a great demand for thinning and lightening, as typified by a cellular phone or a portable information terminal device, which has become popular in recent years. As a result, the optical film used in the display device is also required to be thinner and lighter. For this reason, attempts have been made to make thin films of polymer elongation films more thinner. However, there is a limit to thin films of polymer elongation films due to optical properties or manufacturing process restrictions, and there is a problem that thicker films are used when stacked.

In order to solve such a problem, it is considered effective to use an optical element composed of a liquid crystal material without using a supporting substrate film as in Patent Document 9. However, in order to apply the optical element to a liquid crystal display device, .

In the case of laminating the above-mentioned optical element, handling property and durability are unstable when the support substrate film is absent. On the other hand, if the optical element can be directly laminated on one supporting substrate film holding the polarizing element, omitting the point and adhesive layer not only leads to further reduction in thickness, but also a film excellent in durability and the like can be achieved. An industrial manufacturing method for laminating optical elements has not yet been established.

(1) Patent Document 1: JP-A-4-57017

(2) Patent Document 2: Japanese Patent Application Laid-Open No. 6-242317

(3) Patent Document 3: Japanese Patent Application Laid-Open No. 2002-48917

(4) Patent Document 4: Japanese Patent Application Laid-Open No. 2004-309904

(5) Patent Document 5: Japanese Patent No. 2640083

(6) Patent Document 6: Japanese Patent Application Laid-Open No. 11-194325

(7) Patent Document 7: Japanese Patent Application Laid-Open No. 11-194371

(8) Patent Document 8: Japanese Patent Application Laid-Open No. 2002-31717

(9) Patent Document 9: Japanese Patent Application Laid-Open No. 8-278491

[Disclosure of the Invention]

It is an object of the present invention to provide a polarizing plate which has a structure in which the thickness of the elliptically polarizing plate is reduced and problems such as peeling even under high temperature and high humidity conditions are not caused, A liquid crystal display device using the same, and an electroluminescent display device using the elliptically polarizing plate.

That is, the present invention relates to an elliptically polarizing plate in which a light-transmitting protective film, a polarizing element and an optically anisotropic element are laminated in this order, wherein the optically anisotropic element has at least positive uniaxiality in a twisted nematic orientation And a liquid crystal layer in which the orientation is fixed after hybrid nematic alignment is performed.

(1) A first step of obtaining a laminate (A) composed of a light-transmitting protective film / adhesive layer 1 / polarizing element by adhering a light-transmitting protective film to a polarizing element via an adhesive layer 1, (2) A layer made of a liquid crystalline composition showing at least positive uniaxial property is formed on an alignment substrate subjected to rubbing treatment and this layer is subjected to twisted nematic or hybrid nematic alignment and an optically anisotropic element in which the alignment is fixed is formed (3) a second step of obtaining a laminate (B) composed of an alignment substrate and an optically anisotropic element, (3) a step of irradiating the optically anisotropic element side of the laminate (B) And then the optically anisotropic element is transferred to the layered product (A) to obtain an elliptically polarizing plate composed of the light transmitting protective film / adhesive layer 1 / polarizing element / adhesive layer 2 / optically anisotropic element Each step of the third step A method of producing an elliptically polarizing plate characterized in that at least indirect.

(1) A first step of obtaining a laminate (A) composed of a light-transmitting protective film / adhesive layer 1 / polarizing element by adhering a light-transmitting protective film to a polarizing element via an adhesive layer 1, (2) The surface of the polarizing element of the layered product (A) is subjected to a rubbing treatment to form a layer composed of a liquid crystal composition exhibiting at least positive uniaxiality, and this layer is twisted nematic or hybrid nematic , And an optically anisotropic element in which the orientation is immobilized to obtain an elliptically polarizing plate composed of a light-transmitting protective film / adhesive layer 1 / a polarizing element / an optically anisotropic element at least through each step of the elliptically polarizing plate And a method for producing the same.

The present invention also relates to a liquid crystal display device in which the above-mentioned elliptically polarizing plate is disposed on at least one side of a liquid crystal cell.

The present invention also relates to an electroluminescent display comprising the above-described elliptically polarizing plate.

[Effects of the Invention]

The elliptically polarizing plate of the present invention is hard to cause damage to the optically anisotropic element layer in the step of bonding the optically anisotropic element and the polarizing element, and is excellent in adhesiveness of the optically anisotropic element. In addition, since the number of laminate layers constituting the elliptically polarizing plate is small, there is no interfacial peeling or bubble generation in the durability test. In the process of joining with the polarizing element, the joining can be performed in the form of a elongate film. Therefore, there is an advantage that the joining process can be more rationalized than the conventional method.

Hereinafter, the present invention will be described in detail.

In the present invention, an elliptically polarizing plate is manufactured by bonding an optical anisotropic element directly to a polarizing element or via an adhesive agent. By doing so, the number of layers can be reduced as compared with the elliptically polarizing plate in which the optically anisotropic element is bonded to the polarizing plate in which both sides of the conventional polarizing element are protected by optical films such as triacetyl cellulose film. As a result, it is possible to make the total thickness of the elliptically polarizing plate thinner, reduce the influence of shrinkage deformation due to the difference in elongation and shrinkage behavior of each layer due to heat or humidity, and eliminate the problem of peeling at the bonded interface It is possible.

The layer structure of the elliptically polarizing plate obtained in the present invention has any of the following structures (I) and (II), and if necessary, a member such as a light-transmitting overcoat layer is added again, There is no particular limitation except that an optically anisotropic element composed of a liquid crystal composition exhibiting uniaxial property is formed in a twisted nematic orientation or a hybrid nematic orientation in a liquid crystal state and a liquid crystal layer in which the orientation is fixed. Any structure of (I) or (II) may be used in that an elliptically polarizing plate having a thin thickness is obtained.

(I) Transparent protective film / adhesive layer 1 / polarizing element / adhesive layer 2 / optical anisotropic element

(II) Transparent protective film / adhesive layer 1 / polarizing element / optical anisotropic element

Hereinafter, the constituent members used in the present invention will be described in order. First, the liquid crystal composition used in the present invention will be described.

The optically anisotropic element used in the elliptically polarizing plate of the present invention includes at least a liquid crystal composition in which a liquid crystalline composition exhibiting an optically positive uniaxial property is aligned in a twisted nematic or hybrid nematic orientation in a liquid crystal state, will be. Specifically, it can be obtained by cooling the liquid crystal composition mainly composed of the liquid crystalline polymer oriented on the alignment substrate to a glass transition temperature (Tg) or lower and fixing the orientation. Such a liquid crystal composition is composed of a liquid crystalline polymer composition containing a liquid crystalline polymer as a main component having optically positive uniaxial property and an oyster-like liquid crystal polymer exhibiting liquid crystallinity upon melting is used as the liquid crystalline polymer. It is necessary that the molecular structure of the liquid crystalline phase is maintained even if the liquid crystal polymer is cooled from the molten state (liquid crystal state) to Tg or lower.

The liquid crystal phase at the time of melting of the liquid crystalline polymer may be any molecular alignment structure among smectic, nematic, twisted nematic, cholesteric and the like. Further, in the vicinity of the alignment substrate and air interface, homogeneous alignment or homeotropic alignment Then, a so-called hybrid orientation in which the average director of the liquid crystalline polymer is inclined from the normal direction of the film may be used.

As the liquid crystalline polymer, various main chain type liquid crystalline polymers, side chain type liquid crystalline polymers, or a mixture thereof can be used. Examples of the main chain type liquid crystalline polymer include polyester, polyamide, polycarbonate, polyimide, polyurethane, polybenzimidazole, polybenzoxazole, polybenzothiazole, polyazomethine, Based polymer, a polyester carbonate-based polymer, a polyesterimide-based liquid crystalline polymer, or a mixture thereof. Of these, a semiaromatic polyester-based liquid crystalline polymer in which mesogen groups imparting liquid crystallinity and alternating chains such as polymethylene, polyethylene oxide, and polysiloxane are interlinked and a wholly aromatic polyester-based liquid crystalline polymer having no bending chain are used in the present invention . As the side chain type liquid crystalline polymer, there may be mentioned a substance having a straight chain or cyclic skeleton chain such as polyacrylate, polymethacrylate, polyvinyl, polysiloxane, polyether or polymalonate A liquid crystalline polymer to which a mesogen group is bonded as a side chain, or a mixture thereof. Among them, a side chain type liquid crystalline polymer having a mesogen group bonded to the skeletal chain via a spacer having a bending chain and imparting liquid crystallinity, and a liquid crystalline polymer having a molecular structure having mesogens on both main and side chains, .

In order to induce a twisted nematic orientation, a liquid crystal composition forming a twisted nematic orientation may be prepared by adding a chiral agent to the composition, or adding various liquid crystal materials or non-liquid crystal materials having at least one chiral structural unit It is particularly preferable that the liquid crystal composition is a liquid crystal composition.

Examples of the chiral structural unit include optically active 2-methyl-1,4-butanediol, 2,4-pentanediol, 1,2-propanediol, 2-chloro-1,4-butanediol, 4-butanediol, 2-propyl-1,4-butanediol, 3-methylhexanediol, 3-methyladipic acid, naproxen derivatives, A unit derived from a structural unit derived from camphoric acid, binaphthol, menthol or the like, or a cholesteryl group-containing structural unit or a derivative thereof (for example, a derivative such as a diacetoxy compound) can be used. The structural unit may be any of R-structure and S-structure, or a mixture of R-structure and S-structure. In addition, these structural units are absolutely exemplary and the present invention has no reason to be limited by them.

In addition, even oligomers or low molecular weight liquid crystals can be polymerized by means of thermal crosslinking or photo crosslinking in the liquid crystal state by introduction of a crosslinkable group or by mixing appropriate crosslinking agents, or by cooling to a temperature below the liquid crystal transition temperature, Are included in the liquid crystalline polymer. Also, a discotic liquid crystal compound can be used without any problem. The liquid crystalline polymer is usually one that exhibits an optically positive or negative uniaxial property. These optical properties are appropriately selected according to the function required for the optically anisotropic element, but in the case of the twisted nematic-oriented polymeric liquid crystal layer, a liquid crystalline polymer exhibiting positive uniaxiality is preferably used.

Examples of the low-molecular liquid crystal include a liquid crystal compound selected from the group consisting of a Schiff's salt, a biphenyl-based, terphenyl-based, ester-based, thioester-based, stilbene- A low molecular weight liquid crystal compound having a molecular skeleton such as triphenylene type, truxucene type, phthalocyanine type, and porphyrin type, or a mixture of these compounds. When the liquid crystalline composition composed of the various liquid crystal compounds contains a polymerizable group such as a vinyl group, a (meth) acryloyl group, an epoxy group or an oxetanyl group, it is suitable for each polymerizable group, It is preferable to add various reaction initiators such as various radical initiators or cation generators.

The Tg of the liquid crystal composition is preferably room temperature or higher, more preferably 50 ° C or higher, so as not to affect orientation stability after orientation fixation. The Tg can be adjusted by a liquid crystalline polymer or a low molecular weight liquid crystal used in the liquid crystal composition, a chiral agent, or various compounds as needed, but the crosslinking means as described above may also be used.

The various compounds to be added according to the above-mentioned necessity may be any compound that does not disturb the orientation of the liquid crystal composition used in the present invention and does not deviate from the object of the present invention. In order to form the liquid crystal composition layer uniformly A surfactant, and a stabilizer.

Next, the alignment substrate will be described.

Examples of the alignment substrate include thermosetting resins such as polyimide, epoxy resin and phenol resin; Polyetherimide; Polyether ketones; Polyetheretherketone (PEEK); Polyketone; Polyethersulfone; Polyphenylene sulfide; Polyphenylene oxide; Polyethylene terephthalate; Polyesters such as polyethylene naphthalate and polybutylene terephthalate; Polyacetal; Polycarbonate; Poly (meth) acrylate; A polymer film exemplified by a thermoplastic resin such as polyvinyl alcohol can be used. An organic thin film made of a resin such as polyvinyl alcohol or polyimide derivative may be formed on the surface of the polymer film to control the orientation of the liquid crystal composition. The polymer film is subjected to alignment treatment such as rubbing treatment and is supplied to the alignment substrate.

As described above, in order to align the liquid crystal composition on the alignment substrate, normal rubbing treatment is performed. The rubbing treatment can be performed at an arbitrary angle with respect to the MD direction of the elongated alignment substrate. The angle of the rubbing direction with respect to the MD direction is appropriately set according to the function of the optically anisotropic element, but when the function as the color compensating plate is required, it is preferable that the angle is usually rubbed in the oblique direction with respect to the MD direction. The angle in the oblique direction is preferably in the range of -45 degrees to +45 degrees.

The rubbing treatment can be carried out by any method. For example, a rubbing roll may be arranged at an arbitrary angle with respect to the MD direction of the elongated film on the stage for transporting the elongated film in the MD direction, And the rubbing roll is rotated while the film is transported, thereby rubbing the surface of the film. The angle formed between the rubbing roll and the moving direction of the stage can be freely adjusted, and a suitable rubbing cloth is attached to the surface of the rubbing roll.

Examples of the method of forming the liquid crystalline composition layer by developing the liquid crystalline composition on the rubbing treatment surface of the alignment substrate include a method of dissolving the liquid crystalline composition in a suitable solvent and applying and drying the liquid crystalline composition, And a method of melt extrusion. From the viewpoint of uniformity of the film thickness and the like, a method of applying a solution and drying it is suitable. The solution coating method of the liquid crystalline composition is not particularly limited, and for example, a die coating method, a slot die coating method, a slide die coating method, a roll coating method, a bar coating method, an immersion impression method and the like can be adopted.

After the application, the solvent is removed by an appropriate drying method, and the liquid crystalline composition is heated at a predetermined temperature for a predetermined time to align the liquid crystalline composition in a twisted nematic orientation or a hybrid nematic orientation, and then cooled to Tg or less, The liquid crystal composition layer in which the alignment structure is immobilized can be formed by performing the reaction (curing) by, for example, light irradiation and / or heat treatment to fix the alignment.

The term "the alignment structure is immobilized" means that the alignment structure is maintained without being disturbed under the use conditions. Similarly, the alignment state can be formed in the liquid crystal cell. However, by fixing the alignment structure, a substrate such as glass is not required in the liquid crystal cell, and weight reduction, thinning, improvement in handling properties, and the like can be achieved.

As the light irradiation method, light from a light source such as a metal halide lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, an arc lamp, or a laser such as a spectrum holding an absorption wavelength region of a reaction initiator used is irradiated. The dose per square centimeter is generally in the range of 1 to 2000 mJ, preferably 10 to 1000 mJ as the cumulative dose. However, the case where the spectrum of the light source is remarkably different from the absorption region of the reaction initiator, or the case where the light source wavelength absorbing ability is present in various compounds constituting the liquid crystal composition, and the like are not limited. In such a case, a suitable photosensitizer or a mixture of two or more reaction initiators having different absorption wavelengths may be employed.

The temperature at the time of light irradiation is preferably within a temperature range in which the liquid crystalline composition takes a liquid crystal phase, and in order to sufficiently increase the curing effect, it is preferable to perform light irradiation at a temperature equal to or higher than Tg of the liquid crystalline composition.

The optically anisotropic element used in the elliptically polarizing plate of the present invention includes a liquid crystal layer in which a liquid crystal alignment structure of a twisted nematic orientation or a hybrid nematic orientation is immobilized.

The twisted nematic alignment liquid crystal layer means a layer in which a twisted nematic alignment structure having a structure in which the optic has a shrinkage and a structure in which optical shrinkage is twisted from one side to the other side. Therefore, the optical anisotropic element composed of the twisted nematic alignment liquid crystal layer has properties equivalent to multilayer polymerization in which the optically anisotropic layer is optically twisted so that the shrinkage of the optically anisotropic layer is continuously twisted, and a normal TN (twisted nematic) liquid crystal cell (= DELTA n: a value expressed by a product of birefringence DELTA n and thickness d) and a twist angle, as in the STN (super twisted nematic) liquid crystal cell and the like. The optically anisotropic element may preferably be a temperature compensation type in which the retardation changes when the temperature environment changes and the retardation is restored to its original value when the temperature returns to the original temperature.

The product (Δn · d) of the birefringence Δn of the twisted nematic alignment liquid crystal layer and the thickness d (nm) and the twist angle may be used for a liquid crystal display device or an electroluminescent display device, Is preferably from 50 nm to 1500 nm and the twist angle is from 5 degrees to 400 degrees from the viewpoint of optical properties.

The film thickness of the twisted nematic alignment liquid crystal layer is not particularly limited as long as the function of the optically anisotropic element can be exerted, and about 0.05 to 50 mu m, preferably about 0.1 to 30 mu m, is suitable.

Further, for example, in the case of using the STN-LCD type liquid crystal display device, the DELTA nd and the twist angle of the twisted nematic alignment liquid crystal layer depend on the retardation and the twist angle of the liquid crystal cell to be used, But it is preferably not less than 400 nm and not more than 1200 nm, more preferably not less than 120 but not more than 300 degrees, more preferably not less than 500 nm and not more than 1000 nm, more preferably not less than 160 nor more than 260 degrees, more preferably not less than 600 nor more than 850 nm nor more than 170 nor more than 250 degrees. The twist direction of the twisted nematic alignment liquid crystal layer is preferably opposite to the twist direction of the liquid crystal cell.

In addition, when used as an antireflection film of, for example, a liquid crystal display device or an electroluminescent display device, it is preferable that the twisted nematic alignment liquid crystal layer DELTA n.d for the light having a wavelength of 550 nm is 140 nm or more and 300 nm or less (2) 176 nm or more and 216 nm or less, 58 degrees or more and 70 degrees or less, and (3) a twist angle of 30 degrees or more and 85 degrees or less, More preferably from 230 nm to 270 nm, and from 70 to 80 degrees. There are two types of twist directions, but they may be right twisted or left twisted.

The hybrid nematic alignment liquid crystal layer is a layer including at least a hybrid nematic alignment liquid crystal layer in which a hybrid nematic alignment structure having an average inclination angle of 5 to 45 degrees formed by the liquid crystal composition in a liquid crystal state is immobilized.

Here, the hybrid nematic orientation in the present invention means that the liquid crystal molecules are aligned in a hybrid nematic orientation, and the angles constituted by the directors and liquid crystal layer planes of the liquid crystal molecules at this time are different from each other in the upper and lower surfaces of the layer It says. Therefore, it can be said that the angle changes continuously between the upper surface and the lower surface of the layer in consideration of the fact that the angle formed by the director and the layer plane is different in the vicinity of the upper surface interface and the lower surface interface.

Further, in the hybrid nematic alignment liquid crystal layer in which the hybrid nematic alignment state is immobilized, the directors of the liquid crystal molecules are directed at different angles in the entire film thickness direction of the layer. Therefore, when the layer is a structure called a layer, in the present case, there is no optical axis already.

The average inclination angle in the present invention means an average value of angles formed by the director of the liquid crystal molecules and the plane of the hybrid nematic alignment liquid crystal layer in the film thickness direction of the hybrid nematic alignment liquid crystal layer. In the hybrid nematic alignment liquid crystal layer provided in the present invention, the angle formed by the director and the layer plane in the vicinity of one interface of the layer is an absolute value, usually 25 to 90 degrees, preferably 35 to 85 degrees, And an angle of 45 to 80 degrees. On the opposite side of the surface, the absolute value is usually 0 to 20 degrees, preferably 0 to 10 degrees. The average inclination angle is an absolute value of usually 5 to 45 degrees, Is from 15 to 43 degrees, more preferably from 25 to 40 degrees. When the average inclination angle deviates from the above range, there is a fear that the contrast is lowered when viewed in the oblique direction, which is not preferable. In addition, the average inclination angle can be obtained by applying a crystal rotation method.

The thickness of the liquid crystal layer for the hybrid nematic alignment liquid crystal layer to exhibit a more preferable viewing angle improving effect for the liquid crystal display device depends on the system of the liquid crystal display element to be targeted and various optical parameters. But it is usually in the range of 0.1 탆 to 10 탆, preferably 0.2 탆 to 5 탆, particularly preferably 0.4 탆 to 4 탆. When the film thickness is less than 0.1 탆, there is a possibility that the compensation effect may not be sufficiently obtained. When the film thickness exceeds 10 mu m, the display of the liquid crystal display device may be unnecessarily colored.

In the in-plane apparent retardation value when viewed in the normal direction of the hybrid nematic alignment liquid crystal layer, the refractive index in the direction perpendicular to the director (hereinafter referred to as ne) and the refractive index in the direction perpendicular to the director no), and the value obtained by subtracting no from ne is taken as the apparent birefringence (DELTA n = ne-no), the apparent retardation value is the product of apparent birefringence and absolute thickness (DELTA n · D). This value can be easily obtained by polarimetric optical measurement of an ellipsometer or the like. DELTA nd of the hybrid nematic alignment liquid crystal layer is in the range of usually 10 nm to 400 nm, preferably 30 nm to 200 nm, and particularly preferably 50 nm to 150 nm with respect to monochromatic light at a wavelength of 550 nm. When? N d is less than 10 nm, there is a fear that the effect of enlarging the viewing angle may not be sufficiently obtained. When the thickness is larger than 400 nm, unnecessary coloration may occur in the liquid crystal display device when viewed in the oblique direction.

The detailed arrangement conditions of the hybrid nematic alignment liquid crystal layer in the liquid crystal display device of the present invention will be described below. However, when more specific arrangement conditions are described, the upper and lower portions of the hybrid nematic alignment liquid crystal layer, The inclination direction of the layer and the line oblique direction of the liquid crystal cell layer are respectively defined below.

Firstly, the upper and the lower portions of the optically anisotropic element composed of the hybrid nematic alignment liquid crystal layer are respectively defined according to the angle formed by the liquid crystal molecule director and the plane of the liquid crystal layer in the vicinity of the hybrid nematic interface constituting the optically anisotropic element. The plane constituted by the directors of the molecules and the plane of the liquid crystal layer constitutes an angle of 25 to 90 degrees to the acute angle side is defined as b plane and the plane constituting the angle of 0 to 20 degrees on the acute angle side is defined as c plane .

When viewing the c-plane through the liquid crystal layer from the b-plane of the optically anisotropic element, the angle formed by the projection component on the c-plane of the liquid crystal molecule director and the director is acute and the direction parallel to the projection component Is defined as an oblique direction of the hybrid nematic alignment liquid crystal layer (Figs. 1 and 2).

Next, in general, the driving low-molecular liquid crystal at the cell interface of the liquid crystal cell layer tends to have an angle which is not parallel to the cell interface, and this angle is generally referred to as a line inclination angle. And a direction parallel to the projection component of the director is defined as a line oblique direction of the liquid crystal cell layer (FIG. 3).

Next, the adhesive layer or the light-transmitting overcoat layer used in the present invention will be described.

As a material for forming the adhesive layer or the overcoat layer disposed on the twisted nematic orientation or the hybrid nematic orientation liquid crystal layer or the polarizing element, a twisted nematic alignment liquid crystal layer or a hybrid nematic alignment liquid crystal layer and a polarizing element, Film, and the like, and does not impair the optical characteristics of the respective materials, and examples thereof include acrylic resin, methacrylic resin, epoxy resin, ethylene-vinyl acetate copolymer, rubber, urethane, polyvinyl ether Or a mixture thereof, a thermosetting and / or a photo-curing type, and an electron beam-curing type. These adhesive layers include those having the function of a transparent protective layer (overcoat layer) for protecting the liquid crystal layer. Further, a pressure-sensitive adhesive may be used as the adhesive.

The reaction (curing) conditions of the above reactive components vary depending on conditions such as components constituting the adhesive, viscosity or reaction temperature, and therefore, appropriate conditions may be selected. For example, in the case of a photocurable type, various known photoinitiators are preferably added, and light from a light source such as a metal halide lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, an arc lamp, a laser, a synchrotron radiation source, The reaction may be carried out. The irradiation dose per unit area (1 square centimeter) is usually in the range of 1 to 2000 mJ, preferably 10 to 1000 mJ as the cumulative dose. However, there is no such limitation as when the absorption region of the photoinitiator is significantly different from the spectrum of the light source, or when the reactive compound itself has the ability to absorb the light source wavelength. In these cases, a suitable photosensitizer or a mixture of two or more photoinitiators having different absorption wavelengths may be employed. In the case of the electron beam hardening type, the acceleration voltage is usually 10 kV to 200 kV, preferably 50 kV to 100 kV.

The thicknesses of the adhesive layer and the overcoat layer vary depending on the components constituting the adhesive, the strength of the adhesive, or the use temperature, as described above, but are usually 1 to 30 탆, more preferably 3 to 10 탆. Outside of this range, the adhesive strength is insufficient, or the end portion is exuded, which is not preferable.

In order to control the optical characteristics or to control the peeling property or the erosion property of the substrate, various kinds of fine particles and the surface modifier may be added to these adhesives as long as they do not impair their properties.

Examples of the fine particles include fine particles having a refractive index different from that of the compound constituting the adhesive, conductive fine particles for improving antistatic performance without impairing transparency, and fine particles for improving abrasion resistance. More specifically, Fine alumina, ITO (indium tin oxide) fine particles, silver fine particles, various synthetic resin fine particles, and the like.

The surface modifier is not particularly limited as long as it has good compatibility with the adhesive and does not affect the curing property of the adhesive or the optical performance after curing. Examples of the surface modifier include ionic and nonionic water-soluble surfactants, oil-soluble surfactants, Surfactants, fluorine-based surfactants, organometallic surfactants such as silicones, and reactive surfactants. Particularly, a fluorine surfactant such as a perfluoroalkyl compound, a perfluoropolyether compound or the like or an organometallic surfactant such as silicon is particularly preferable because of its large surface modification effect. The addition amount of the surface modifier is preferably 0.01 to 10 mass%, more preferably 0.05 to 5 mass%, and still more preferably 0.1 to 3 mass% with respect to the adhesive. If the addition amount is less than this range, the effect of addition becomes insufficient, while if it is excessively large, adverse effects such as too low bonding strength may occur. The surface modifying agent may be used alone or in combination with a plurality of types as necessary.

Furthermore, various additives such as an antioxidant and an ultraviolet absorber may be added within the range not to impair the effect of the present invention.

The polarizing element usable in the present invention is not particularly limited, and various polarizing elements can be used. Examples of the polarizing element include a hydrophilic polymer film such as a polyvinyl alcohol film, a partially polymerized polyvinyl alcohol film, and an ethylene / acetylene vinyl copolymer system partially saponified film, and a dichroic substance such as iodine or a dichroic dye is adsorbed And polyene-based oriented films such as dehydrochloric acid-treated polyvinyl chloride films. Among them, a polyvinyl alcohol film is preferably stretched and a dichroic material (iodine, dye) is adsorbed and oriented. The thickness of the polarizing element is not particularly limited, but is generally about 5 to 50 mu m.

The polarizing element obtained by dying a polyvinyl alcohol film with iodine and uniaxially stretching can be produced by, for example, dying polyvinyl alcohol in an aqueous solution of iodine and stretching it to 3 to 7 times the original length. If necessary, it may be immersed in an aqueous solution of boric acid or potassium iodide. Further, if necessary, the alcohol film may be dipped in water and washed with water before dyeing. The polyvinyl alcohol film is washed with water to clean the surface of the polyvinyl alcohol film surface and the antiblocking agent, and the polyvinyl alcohol film is swollen to prevent unevenness such as uneven dyeing. The stretching may be carried out after dyeing with iodine, the stretching while dyeing, or the stretching and dyeing with iodine. It can be stretched either in an aqueous solution such as boric acid or potassium iodide or in a water bath.

As the translucent protective film disposed on one side of the polarizing element, an optically isotropic film is preferable. For example, triacetylcellulose such as Fujitack (manufactured by Fuji Photo Film Co., Ltd.) and Konica Kattaku (manufactured by Konica Corp.) (TAC) film; (Manufactured by Mitsui Chemicals, Inc.), acryprene film (manufactured by Mitsubishi Chemical Corporation), and the like, such as Artonfilm (manufactured by JSR Corporation), ZeonoaFilm and Zeonexfilm (manufactured by Nippon Zeon) Triacetyl cellulose, and cycloolefin-based polymers are preferable because of planarity, heat resistance, moisture resistance, etc. in the case of using an elliptically polarizing plate. The thickness of the translucent protective film is generally preferably from 1 to 100 mu m, more preferably from 5 to 50 mu m.

As the translucent protective film, a hard coat layer or a film subjected to a treatment for the purpose of anti-reflection treatment, anti-sticking, light diffusion or anti-glare may be used.

The hard coat treatment is carried out for the purpose of preventing the surface of the polarizing plate from being damaged or the like, for example, by a method in which a cured film excellent in hardness or slipperiness due to a suitable ultraviolet curable resin such as acrylic or silicone is added to the surface of the protective film . The antireflection treatment is carried out for the purpose of preventing the reflection of external light on the surface of the polarizing plate and can be achieved by forming an antireflection film or the like as in the prior art. Further, the anti-sticking treatment is carried out for the purpose of preventing adhesion to the adjacent layer.

The anti-glare treatment is carried out for the purpose of preventing external light from being reflected from the surface of the polarizing plate and hindering the visibility of the light transmitted through the polarizing plate. For example, the anti-glare treatment may be carried out by a sandblasting method or an embossing method, Or by giving a micro concavo-convex structure to the surface of the protective film in an appropriate manner. Examples of the fine particles contained in the formation of the surface micro concavo-convex structure include conductive particles containing silica, alumina, titania, zirconia, silver oxide, indium oxide, cadmium oxide, antimony oxide or the like having an average particle diameter of 0.5 to 50 μm Organic fine particles including inorganic fine particles, crosslinked or uncrosslinked polymers, and the like can be used. In the case of forming the surface micro concavo-convex structure, the amount of the fine particles to be used is generally about 2 to 50 parts by weight, preferably 5 to 25 parts by weight per 100 parts by weight of the transparent resin forming the surface micro concavo-convex structure. The anti-glare layer may have a light diffusion layer (a magnifying function for viewing, etc.) for diffusing the polarized-plate transmitted light to enlarge the viewing angle or the like.

The antireflection layer, the anti-sticking layer, the light diffusion layer, the anti-glare layer, and the like can be disposed not only on the light transmissive protective film itself, but also as a separate optical layer separate from the light transmissive protective film.

Next, the method for producing the elliptically polarizing plate of the present invention will be described in detail.

The layer configuration of the elliptically polarizing plate obtained in the present invention is selected from the following two types as shown in Figs. 4 and 5.

(1) Transparent protective film / adhesive layer 1 / polarizing element / adhesive layer 2 / optical anisotropic element

(2) Transparent protective film / adhesive layer 1 / polarizing element / optical anisotropic element

The method for producing the elliptically polarizing plate is not particularly limited, but it can be produced by the following method as an example.

First, the manufacturing method of the structure (I) will be described.

The composition (I)

(1) a first step of obtaining a layered product (A) comprising a light-transmitting protective film / adhesive layer 1 / polarizing element by adhering a light-transmitting protective film to a polarizing element via an adhesive layer 1,

(2) A layer made of a liquid crystalline composition exhibiting at least positive uniaxial property is formed on an alignment substrate subjected to rubbing treatment, and this layer is subjected to twisted nematic or hybrid nematic alignment, A second step of forming a device to obtain a layered product (B) composed of an orientation substrate / optically anisotropic element,

(3) The optically anisotropic element side of the layered product (B) is adhered to the polarizing element side of the layered product (A) via the adhesive layer 2, and then the oriented substrate is peeled off, A) to obtain an elliptically polarizing plate composed of a light transmitting protective film / adhesive layer 1 / polarizing element / adhesive layer 2 / optically anisotropic element

And at least the steps of FIG.

Hereinafter, the manufacturing method from the first step to the third step will be described in order.

First, a method of manufacturing the layered product (A) which is the first step will be described.

After the adhesive layer 1 is formed on the polarizing element, the light-transmitting protective film and the polarizing element are closely contacted with each other through the adhesive layer 1, and the adhesive layer is reacted (cured) if necessary. Thus, the layered product (A) obtained by bonding on the light transmitting protective film through the adhesive layer 1 can be obtained.

Next, a method for producing the layered product (B) which is the second step will be described.

After rubbing the substrate with a foil or the like on the alignment substrate, a coating film of a liquid crystalline composition exhibiting at least positive uniaxiality is formed by a suitable method, and if necessary, the solvent or the like is removed and heated to form a twisted nematic Alignment or hybrid nematic alignment is completed, and the orientation of the liquid crystalline composition is fixed according to a suitable means for the liquid crystalline composition used. Thus, a layered product (B) having a liquid crystal layer in which a twisted nematic orientation or a hybrid nematic orientation is immobilized can be obtained on an alignment substrate.

Next, the manufacturing method of the third step will be described.

After the side of the twisted nematic orientation or the hybrid nematic alignment liquid crystal layer (optically anisotropic element) of the laminate (B) is brought into close contact with the side of the polarizing element of the laminate (A) through the adhesive layer 2, After the adhesive layer is reacted (cured), the alignment substrate is peeled off and the optically anisotropic element is transferred to the layered product (A).

Thus, the elliptically polarizing plate of the present invention including the light-transmitting protective film / adhesive layer 1 / polarizing element / adhesive layer 2 / optical anisotropic element can be obtained.

When the twisted nematic alignment of the layered product (B) or the transfer of the hybrid nematic alignment liquid crystal layer into the layered product (A) is carried out, the liquid crystal layer is transferred onto a substrate different from the alignment substrate as necessary, It may be re-transferred to the sifter (A).

In order to protect the surface of the optically anisotropic element layer of the obtained elliptically polarizing plate, a light-transmitting overcoat layer may be disposed or a temporary surface protective film may be bonded. Here, the light-transmitting overcoat may be selected from among the above-mentioned adhesives.

Next, a manufacturing method of the structure (II) will be described.

The composition (II)

(1) A first step of obtaining a laminate (A) composed of a light-transmitting protective film / adhesive layer 1 / polarizing element by adhering a light-transmitting protective film to a polarizing element via an adhesive layer 1,

(2) The polarizing element of the layered product (A) is subjected to a rubbing treatment to form a layer composed of a liquid crystalline composition exhibiting at least positive uniaxiality, and this layer is subjected to twisted nematic or hybrid nematic orientation , And an optically anisotropic element in which the orientation is immobilized to form an elliptically polarizing plate composed of a light-transmitting protective film / adhesive layer 1 / polarizing element / optical anisotropic element.

Hereinafter, the manufacturing method from the first step to the second step will be described in order.

First, the manufacturing method of the layered product (A) which is the first step is the same as the constitution (I).

The manufacturing method of the second step will be described.

The polarizing element of the layered product (A) produced in the first step is subjected to rubbing treatment to form a coating film of a liquid crystalline composition exhibiting at least positive uniaxial property by a suitable method, and if necessary, the solvent or the like is removed, The twisted nematic or hybrid nematic orientation of the liquid crystalline composition is completed, and the orientation of the liquid crystalline composition is fixed by means suitable for the liquid crystalline composition used. Thus, an elliptically polarizing plate including a transparent protective film / adhesive layer 1 / polarizing element / optical anisotropic element having an optically anisotropic element composed of a liquid crystal layer in which a twisted nematic or hybrid nematic liquid crystal alignment was immobilized was laminated on the laminate A .

For the purpose of protecting the surface of the optically anisotropic element layer of the obtained elliptically polarizing plate, a light-transmitting overcoat layer may be disposed or a temporary surface protective film may be bonded. Here, the light-transmitting overcoat may be selected from the above-mentioned adhesives.

Further, in a second step of the structure (II), an orientation film suitable for nematic orientation of the liquid crystal composition is arranged on the polarizing element in accordance with the orientation of the polarizing element to the liquid crystal composition, and then rubbing is performed, Is also included in the present invention (Fig. 6).

In the present invention, it is also possible to laminate a plurality of optically anisotropic element layers by repeatedly laminating the optically anisotropic element layers on the alignment substrate through an adhesive layer or an adhesive layer.

It is preferable that the light-transmitting protective film or polarizing element used for producing the layered product (A) is surface-treated.

Examples of the surface treatment include saponification treatment, corona discharge treatment, flame treatment, low-pressure UV irradiation, plasma treatment, and the like, as appropriate methods for the light-transmitting protective film or polarizing element. More preferably, as the light transmitting protective film, for example, saponification treatment is used when triacetyl cellulose is used, and corona discharge treatment when a cycloolefin polymer is used. The polarizing element is preferably subjected to a corona discharge treatment.

The saponification treatment is carried out by contacting an aqueous alkali solution, which is a conventional method. As the alkali aqueous solution, potassium hydroxide, sodium hydroxide, or the like is used, and as the alkali concentration, about 0.1 to 10 mass%, preferably 0.5 to 5 mass%, and more preferably about 1 to 3 mass% Do. As the treatment conditions, a mild condition at room temperature for 1 to 60 minutes, preferably 30 minutes or less, more preferably 15 minutes or less is sufficient. Needless to say, it is necessary to sufficiently wash the water after the treatment.

Similar to the saponification treatment, the corona discharge treatment is also carried out on the surface of the substrate which is isotropic in contact with the pressure-sensitive adhesive layer, under normal conditions. The treatment conditions depend on the type of the substrate and the corona treatment apparatus to be used, but it is preferable that the energy density is 1 to 300 W · min / m 2, for example. The surface tension is increased by the corona discharge treatment, but it is preferably higher than 40 dyn / cm.

The formation of the point / adhesive layer may be carried out in the same manner as the formation of the above-described liquid crystalline composition layer. Further, a so-called non-support point adhesive in which the point / adhesive layer is formed on a suitable substrate subjected to easy peeling treatment It may be used. The optical anisotropic element and the polarizing element may be subjected to pressure heating by using a laminator, a roller, a pressurizer or the like for the purpose of improving the bonding strength and preventing the generation of air bubbles due to the remaining air on the bonding interface.

The optical anisotropic element, the polarizing element, and the translucent hobob film can be laminated successively in a state in which they are aligned in the MD direction in the form of elongated films when they are bonded.

In addition to the above-mentioned manufacturing methods, these three methods may also be used in which the optical anisotropic element and the light-transmitting protective film are bonded to both sides of the polarizing element at the same time, or the optical anisotropic element and the light- .

The total thickness of the elliptically polarizing plate of the present invention thus obtained varies depending on the thickness of each of the light-transmitting protective film, polarizing element, adhesive, optical anisotropic element, and the like, but is preferably 150 탆 or less, and more preferably 100 탆 or less. When the total thickness exceeds 150 탆, when the elongated film is wound in a predetermined length on the roll, the roll diameter becomes too large, which makes it difficult to store in a conventional transportation packaging container, Which is not preferable.

Further, an elliptically polarizing plate in which at least one optical film is laminated may be used in addition to the elliptically polarizing plate of the present invention.

The optical film is not particularly limited as long as it is excellent in transparency and uniformity, but a liquid crystalline film comprising a polymer stretched film or liquid crystal can be preferably used. Examples of the polymer stretched film include monoaxial or biaxial retardation films made of cellulose, polycarbonate, polyarylate, polysulfone, polyacrylic, polyether sulfone, cyclic olefin polymer, and the like. Among them, a polycarbonate-based or cyclic olefin-based polymer is preferable in terms of cost and film uniformity.

The liquid crystal film made of the liquid crystal referred to herein is not particularly limited as long as it is a film that can orient the liquid crystal and utilize the optical anisotropy generated in the aligned state. Known optically functional films such as nematic liquid crystals or discotic liquid crystals, smectic liquid crystals and the like can be used.

The molecular alignment structure of the liquid crystalline film may be any molecular alignment structure among Smectic, Nematic, Twisted Nematic, Cholesteric and the like. In the vicinity of the alignment substrate and the vicinity of the air interface, homogeneous alignment and homeotropic alignment Called hybrid alignment in which the average director of the liquid crystalline polymer is inclined from the normal direction of the film.

The optical film exemplified here may be used in a single sheet or in a plurality of sheets each time the liquid crystal display device is constituted. Further, both the polymer stretched film and the liquid crystal film may be used.

Hereinafter, a liquid crystal display device to which the elliptically polarizing plate of the present invention is applied will be described.

The liquid crystal display of the present invention holds at least the elliptically polarizing plate. When the elliptically polarizing plate of the present invention is disposed in the liquid crystal cell, it is necessary to dispose the optically anisotropic element side of the elliptically polarizing plate on the liquid crystal cell side.

The liquid crystal display device generally comprises a polarizing plate, a liquid crystal cell, and a member such as a retardation compensating plate, a reflecting layer, a light diffusing layer, a backlight, a front light, a light control film, a light guide plate, a prism sheet, There is no particular limitation except that The position of use of the elliptically polarizing plate is not particularly limited, and may be one position or plural positions.

The polarizing plate used in the liquid crystal display device is not particularly limited, and any one obtained from the same polarizing element can be used as long as it is used in the above-mentioned elliptically polarizing plate.

The liquid crystal cell is not particularly limited, and a common liquid crystal cell such as a liquid crystal layer interposed between a pair of transparent substrates provided with electrodes can be used.

The transparent substrate constituting the liquid crystal cell is not particularly limited as long as the material exhibiting liquid crystallinity constituting the liquid crystal layer is oriented in a specific alignment direction. Specifically, any of a transparent substrate having a property that the substrate itself has a property of aligning liquid crystals, a transparent substrate provided with an alignment film having a property of aligning liquid crystals thereon, etc. may be used. A well-known electrode can be used for the liquid crystal cell. Usually, the liquid crystal layer can be provided on the surface of the transparent substrate on which the liquid crystal layer is in contact. In the case of using the substrate having the alignment film, the liquid crystal layer can be provided between the substrate and the alignment film.

The material exhibiting liquid crystallinity forming the liquid crystal layer is not particularly limited, and examples thereof include various ordinary low-molecular liquid crystal materials, polymer liquid crystal materials, and mixtures thereof capable of forming various liquid crystal cells. In addition, a dye, a chiral agent, a non-liquid crystalline substance and the like may be added to these to the extent that liquid crystallinity is not impaired.

In addition to the electrode substrate and the liquid crystal layer, the liquid crystal cell may have various components necessary for forming liquid crystal cells of various types described later.

Examples of the liquid crystal cell include TN (Twisted Nematic), STN (Super Twisted Nematic), ECB (Electrically Controlled Birefringence), IPS (In-Plane Switching), VA (Vertical Alignment) Various schemes such as a Birefringence method, a HAN (Hybrid Aligned Nematic) method, an ASM (Axially Symmetric Aligned Microcell) method, a halftone gray scale method, a domain division method or a ferroelectric liquid crystal display method using an antiferroelectric liquid crystal .

There is also no particular limitation on the driving method of the liquid crystal cell. Passive matrix method that can be used for STN-LCD or the like and active matrix method using active electrodes such as TFT (Thin Film Transistor) electrode and TFD , A plasma addressing method, or the like.

When the elliptically polarizing plate of the present invention is applied to a liquid crystal display device, it is preferable that the elliptically polarizing plate is located closer to the observer side (front side) than the liquid crystal cell of the liquid crystal display device, As shown in Fig.

The retardation compensating plate can be appropriately selected from the optical film used in the present invention described above, and the retardation compensating plate can be used in one sheet, or a plurality of sheets can be used. Further, both of a polymer stretched film and an optical compensation film composed of a liquid crystal may be used.

Examples of the reflective layer include, but are not limited to, metals such as aluminum, silver, gold, chromium, and platinum, alloys containing them, oxides such as magnesium oxide, multilayer films of dielectrics, liquid crystals showing selective reflection, . These reflective layers may be planar or curved. The reflective layer may have a diffuse reflectivity by being processed to have a surface shape such as a concavo-convex shape or the like; an electrode on the electrode substrate opposite to the observer side of the liquid crystal cell; a reflective layer which is thinned, Or the like, and may be a transflective layer that allows a part of light to be transmitted therethrough, or a combination thereof.

The light diffusion layer is not particularly limited as long as it has a property of diffusing incident light isotropically or anisotropically. For example, it may be composed of two or more kinds of regions, having a difference in refractive index between the regions, or having irregularities on the surface shape. Examples of the two or more kinds of regions having a refractive index difference between the regions include particles in which a particle having a refractive index different from that of the matrix is dispersed in the matrix. The light-diffusing layer itself may have a self-adhesive property.

The thickness of the light-diffusing layer is not particularly limited, but is usually preferably 10 탆 or more and 500 탆 or less.

The total light transmittance of the light-diffusing layer is preferably 50% or more, more preferably 70% or more. The haze value of the light-diffusing layer is usually 10 to 95%, preferably 40 to 90%, more preferably 60 to 90%.

The backlight, the front light, the light control film, the light guide plate, and the prism sheet are not particularly limited and publicly known ones can be used.

The liquid crystal display device of the present invention can be provided with other constituent members in addition to the above-described constituent members. For example, by attaching a color filter to the liquid crystal display device of the present invention, a color liquid crystal display device capable of performing multicolor or pure color display with high color purity can be manufactured.

Next, an organic electroluminescent display device (organic EL display device) to which the elliptically polarizing plate of the present invention is applied will be described.

In general, in an organic EL display device, a transparent electrode, an organic light emitting layer, and a metal electrode are sequentially laminated on a transparent substrate to form a light emitting body (organic electroluminescent light emitting element). Here, the organic luminescent layer is a laminate of various organic thin films, for example, a laminate of a hole injection layer composed of a triphenylamine derivative or the like and a luminescent layer composed of a fluorescent organic solid such as anthracene, or a laminate of such a luminescent layer and a phenylene derivative Layered structure of the electron injection layer, or a laminate of the hole injection layer, the light-emitting layer and the electron injection layer, and the like are known.

In the organic EL display device, when a voltage is applied to the transparent electrode and the metal electrode, holes and electrons are injected into the organic light emitting layer, and the energy generated by the recombination of the holes and the electrons excites the fluorescent substance, It emits light on the principle of emitting light when going back. The mechanism of recombination in the middle, like the ordinary diode, can be expected from these, the current and the light emission intensity show strong nonlinearity accompanied by rectification with respect to the applied voltage.

In the organic EL display device, at least one of the electrodes must be transparent in order to emit light from the organic light emitting layer, and a transparent electrode usually formed of a transparent conductor such as indium tin oxide (ITO) is used as the anode. On the other hand, in order to facilitate the electron injection and increase the luminous efficiency, it is important to use a material having a small duty function on the cathode, and metal electrodes such as Mg-Ag and Al-Li are generally used.

In the organic EL display device having such a structure, the organic luminescent layer is formed with an extremely thin film with a thickness of about 10 nm. Therefore, the organic light-emitting layer almost completely transmits the light, like the transparent electrode. As a result, light emitted from the surface of the transparent substrate at the time of non-emission and transmitted through the transparent electrode and the organic light-emitting layer and then reflected by the metal electrode is again emitted to the surface side of the transparent substrate. The face looks like a mirror face.

An organic electroluminescent display device comprising an organic electroluminescent light emitting element having a transparent electrode on a surface side of an organic light emitting layer emitting light by application of a voltage and a metal electrode on a back surface side of the organic light emitting layer, And a phase difference plate can be provided between the transparent electrode and the polarizing plate.

The retardation plate and the polarizing plate have the effect of being polarized light that is incident from the outside and reflected from the metal electrode so that the mirror surface of the metal electrode can not be visually recognized from the outside by the polarizing action. In particular, the mirror surface of the metal electrode can be completely shielded by configuring the retarder plate as a quarter wave plate and adjusting the angle formed by the polarizing direction of the polarizer and the retarder to be π / 4.

That is, only the linearly polarized light component is transmitted through the polarizing plate by external light incident on the organic EL display device. This linearly polarized light is usually elliptically polarized by the retardation plate, but particularly when the retardation plate is a quarter wave plate and the angle constituted by the polarizing direction of the polarizing plate and the retardation plate is π / 4, it becomes circularly polarized light.

The circularly polarized light passes through the transparent substrate, the transparent electrode, and the organic thin film, is reflected by the metal electrode, passes again through the organic thin film, the transparent electrode, and the transparent substrate, and becomes linearly polarized again in the retarder. Therefore, since this linearly polarized light is orthogonal to the polarization direction of the polarizing plate, it can not transmit through the polarizing plate. As a result, the mirror surface of the metal electrode can be completely shielded.

When the elliptically polarizing plate of the present invention is applied to the organic EL display device, it is preferable to arrange it on the observer side (front side) of the organic EL display device as viewed from the observer side in order to prevent reflection of external light as described above .

[Industrial Availability]

The elliptically polarizing plate of the present invention is characterized in that the number of laminate layers constituting the elliptically polarizing plate is small, and no interface separation or bubble generation occurs under high temperature and high humidity conditions. In addition, the bonding process with the polarizing element can be performed in the form of a long film, so that the bonding process can be rationalized, which is of great industrial value.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited thereto.

The analytical methods used in the examples are as follows. In this embodiment, optical parameters such as DELTA n d are values at a wavelength of 550 nm unless otherwise specified.

(1) Measurement of log viscosity

Was measured at 30 캜 in a mixed solvent of phenol / tetrachloroethane (60/40 by mass ratio) using a Ubero type viscometer.

(2) Microscopic observation

And the alignment state of the liquid crystal was observed with a BH2 polarization microscope manufactured by Olympus Optics.

(3) Polarization analysis measurement of the liquid crystal composition layer

And an ellipsometer (DVA-36VWLD) manufactured by Mizogiri Gokaku Co., Ltd. was used.

(4) Measurement of DELTA nd and twist angle of the liquid crystal composition layer

RETS-100 manufactured by Otsuka Electronics Co., Ltd. was used.

(5) Parameter measurement of hybrid nematic alignment liquid crystal layer

The automatic reprographic system KOBRA21ADH manufactured by Oji Scientific Instruments Co., Ltd. was used.

(6) Measurement of film thickness

SURFACE TEXTURE ANALYSIS SYSTEM manufactured by SLOAN (Dektak 3030ST) was used. In addition, a method of obtaining the film thickness from the interference wave measurement (V-570, ultraviolet, visible, near infrared spectrophotometer V-570, manufactured by Nippon Gosei Co., Ltd.) and refractive index data was also used.

≪ Example 1 >

(1) Construction of laminate A

The TAC film (40 mu m, manufactured by Fuji Photo Film Co., Ltd.) was immersed in a 2 mass% aqueous solution of potassium hydroxide for 5 minutes at room temperature, saponified, washed in water and dried. A saponified TAC film was bonded to one side of the polarizing element in which iodine was adsorbed on the stretched polyvinyl alcohol using an acrylic adhesive as the adhesive layer 1 to obtain a laminate A. The total film thickness was 65 占 퐉 and thinner than the conventional one (105 占 퐉).

(Preparation of liquid crystalline composition solution B and laminate D)

50 mmol of terephthalic acid, 50 mmol of 2,6-naphthalenedicarboxylic acid, 40 mmol of methylhydroquinone diacetate, 60 mmol of catechol diacetate and 60 mg of N-methylimidazole were subjected to polymerization at 270 DEG C for 12 hours under a nitrogen atmosphere. The obtained reaction product was dissolved in tetrachloroethane and purified by reprecipitation with methanol to obtain 14.7 g of a liquid crystalline polyester (polymer 1). The liquid crystalline polyester had a logarithmic viscosity of 0.17 (dl / g), a nematic phase as a liquid crystal phase, an isotropic liquid crystal phase transition temperature of 250 占 폚 or higher and a glass transition point of 115 占 폚.

Subsequently, 90 mmol of biphenyldicarbonyl chloride, 10 mmol of terephthaloyl chloride and 105 mmol of S-2-methyl-1,4-butanediol were reacted at room temperature for 20 hours in dichloromethane, and the reaction solution was poured into methanol to reprecipitate, 12.0 g of a gum polyester (polymer 2) was obtained. The logarithmic viscosity of the polymer 2 was 0.12 (dl / g).

A liquid crystal composition containing a mixed polymer composed of 19.82 g of the polymer 1 and 0.18 g of the polymer 2 was prepared, and a liquid crystal composition solution B was prepared by preparing a? -Butyrolactone solution of 8% by mass.

A 150 mm diameter rubbing roll with a rayon cloth was installed at an angle while rotating the elongated PEEK film having a width of 650 mm and a thickness of 100 m and rubbed continuously at a high speed to obtain an oriented substrate film having a rubbing angle of 25 degrees. Here, the rubbing angle means an angle in a direction counterclockwise from the MD direction when the rubbing surface is viewed from above. The liquid crystalline composition solution B was continuously coated on the orientation substrate film using a die coater and dried, and then the liquid crystalline composition was oriented by heating at 150 DEG C for 10 minutes and then cooled to room temperature to fix the alignment, Layer (optical anisotropic element) and a PEEK film.

The thickness of the obtained liquid crystalline composition layer of the layered product D was 4 占 퐉.

Since the birefringence of the PEEK film used as the alignment substrate is large, it is difficult to measure the optical parameters of the liquid crystalline composition layer in the form of the layer D, and the liquid crystalline composition layer is transferred onto the triacetyl cellulose (TAC) film as follows.

That is, an ultraviolet curable adhesive was applied on the liquid crystalline composition layer on the PEEK film so as to have a thickness of 5 mu m, laminated on a TAC film (40 mu m thick, manufactured by Fuji Photo Film Co., Ltd.) , The PEEK film was peeled off to obtain a laminate composed of the liquid crystal composition layer / adhesive layer / TAC film. The obtained laminate was subjected to parameter measurement by RETS-100 manufactured by Otsuka Electronics Co., Ltd. As a result, twisted nematic alignment was obtained. The twist angle was -240 deg. And DELTA nd was 800 nm.

(Construction of elliptically polarizing plate E)

A commercially available UV curable adhesive (UV-3400, manufactured by Donga Synthetic Co., Ltd.) was applied on the optically anisotropic element of the layered product D as an adhesive layer 2 with a thickness of 5 탆, and the polarizing element side of the thus- And the adhesive layer 2 was cured by UV irradiation of about 600 mJ. Thereafter, the PEEK film was peeled off from the laminate in which the PEEK film / optical anisotropic element / adhesive layer 2 / polarizing element / adhesive layer 1 / TAC film were integrated, and the optically anisotropic element was transferred onto the laminate A to remove the TAC film / An elliptically polarizing plate E composed of layer 1 / polarizing element / adhesive layer 2 / optically anisotropic element was obtained. The total thickness of this elliptically polarizing plate E was 75 탆.

As a result of optical inspection of this elliptically polarizing plate E, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate E was adhered to a glass plate via an acrylic adhesive, placed in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

≪ Example 2 >

(Preparation of adhesive)

As an urethane-based adhesive, 100 parts of "EL-436A" (an aqueous solution having a solid content concentration of 35% by mass), which is a main polyester polyol precursor polymer, was added with 100 parts of an isocyanate-based curing agent "EL -436B "(product of 100% active ingredient), and further diluted with water to a solid concentration of 20%. On the other hand, as a polyvinyl alcohol-based adhesive, there was used a gelatine-modified polyvinyl alcohol "Kurarupofaru KL318" (a saponification product of a copolymer having a molar ratio of vinyl acetate and sodium itaconate of about 98: 2, 90 mol%, molecular weight: about 85,000) 3% aqueous solution was prepared. The resulting urethane-based adhesive and a polyvinyl alcohol aqueous solution were mixed at a mass ratio of 1: 1 (solid content: mass ratio of 20: 3) to prepare a mixed adhesive.

(Construction of laminate F)

A polarizing element having iodine adsorbed on the stretched polyvinyl alcohol was coated on one side with a mixed adhesive prepared as the adhesive layer 1 within one minute, and a Zeonoa film (film thickness: 40 m, manufactured by Japan Xionics Co., Ltd.) Was subjected to a corona treatment under the conditions of 250 W · min / m 2 and bonded to the corona-treated surface within 30 seconds after the corona treatment to construct a laminate F. The total film thickness was about 65 占 퐉, which was thinner than the conventional one (105 占 퐉).

(Construction of elliptically polarizing plate G)

A commercially available UV curable adhesive (UV-3400, manufactured by Donga Synthetic Co., Ltd.) was applied as an adhesive layer 2 to a thickness of 5 탆 on the optically anisotropic element of the prepared layered product D in Example 1, And the adhesive layer 2 was cured by UV irradiation of about 600 mJ. Thereafter, the PEEK film was peeled off from the laminate in which the PEEK film / optical anisotropic element / adhesive layer 2 / polarizing element / adhesive layer 1 / Zeonoa film were integrated, and the optically anisotropic element was transferred onto the laminate F, / Adhesive layer 1 / polarizing element / adhesive layer 2 / elliptically polarizing plate G composed of optical insulator. The total thickness of this elliptically polarizing plate G was 75 탆.

As a result of optical inspection of this elliptically polarizing plate G, no damage such as stains or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate G was adhered to a glass plate through an acrylic adhesive, placed in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

≪ Example 3 >

(Construction of elliptically polarizing plate H)

A solution of the liquid crystal composition prepared by varying the mixing ratio of polymer 1 and polymer 2 synthesized in Example 1 on the side of the polarizing element of Working Example 2 was successively coated with a die coater and dried, × 10 minutes to align the liquid crystal composition. Subsequently, the orientation was fixed by cooling to room temperature to obtain an elliptically polarizing plate H composed of the Zeonoah film / adhesive layer 1 / polarizing element / optical anisotropic element. The total thickness of this elliptically polarizing plate H was 70 탆.

The optically anisotropic element layer had a twisted nematic orientation, the twist angle was -65 degrees, and nd was 190 nm. The elliptically polarizing plate was subjected to a polarization analysis with an ellipsometer (DVA-36VWLD, manufactured by Mizogiri Gokaku Co., Ltd.). As a result, it was confirmed that the ellipticity was 0.94 at a wavelength of 550 nm and was a circularly polarizing plate having good circularly polarized light characteristics.

As a result of optical inspection of this elliptically polarizing plate H, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate H was adhered to a glass plate via an acrylic adhesive, placed in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

<Example 4>

(Construction of laminate J)

A 5 mass% solution of an alkyl-modified polyvinyl alcohol (PVA, PVA-117H, manufactured by Kuraray Co., Ltd.) (having a mass ratio of water to isopropyl alcohol of 1: 1) was continuously coated with a die coater, dried, and heat-treated at 130 캜 to obtain a laminate J composed of a Zeonoa film / adhesive layer 1 / polarizing element / PVA alignment film.

(Construction of elliptically polarizing plate K)

The liquid crystalline composition solution B prepared in Example 1 was continuously applied and dried on the PVA alignment layer of the layered product J using a die coater and then heat-treated at 150 캜 for 10 minutes to align the liquid crystal composition. Subsequently, the film was cooled to room temperature to fix the orientation, thereby obtaining an elliptically polarizing plate K composed of Zeonoia film / adhesive layer 1 / polarizing element / PVA alignment film / optical anisotropic element. The total thickness of this elliptically polarizing plate K was 73 탆.

As a result of optical inspection of this elliptically polarizing plate K, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate K was adhered to a glass plate via an acrylic adhesive, placed in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

&Lt; Comparative Example 1 &

(Construction of laminate L)

In Example 1, the side of the optically anisotropic element of the patterned layered product D was transferred to a triacetylcellulose (TAC) film (40 m) through an ultraviolet curable adhesive. That is, the adhesive is applied on the optically anisotropic element on the PEEK film so as to have a thickness of 5 탆, laminated on the TAC film, and the adhesive is cured by irradiating ultraviolet rays from the TAC film side, Optical anisotropic element / adhesive layer / TAC film).

(Construction of elliptically polarizing plate N)

A polarizing plate M was prepared by bonding a saponified TAC film to both sides of a polarizing element in which iodine was adsorbed on stretched polyvinyl alcohol using an acrylic adhesive.

An optically anisotropic element side of the laminate L was bonded to the polarizing plate M via an acrylic pressure-sensitive adhesive to form an elliptically polarizing plate N. Since the elliptically polarizing plate N is twice as thick as about 200 탆 in thickness, and the winding thickness becomes large, the processing length in one operation can not be shortened as compared with the construction of the elliptically polarizing plate of Examples 1 to 4.

An acrylic pressure-sensitive adhesive was applied to a TAC film on the optically anisotropic element side of the elliptically polarizing plate N and adhered to a glass plate. As a result of performing the same test as in Example 1, peeling of 0.5 mm at the end was observed after 500 hours passed.

&Lt; Example 5 >

Using the elliptically polarizing plate E obtained in Example 1, an STN transmissive liquid crystal display device was constructed in the arrangement as shown in Fig. In the present embodiment, the apparatus was constructed by setting the counterclockwise rotation direction to + from the polarizing element 4 side toward the liquid crystal cell 8 side and the clockwise rotation direction to -, but the polarizing element 4 to the liquid crystal cell 8 side It is presupposed that exactly the same result is obtained even if the same experiment is carried out by setting the clockwise rotation direction to + and the counterclockwise rotation direction to -.

FIG. 8 shows the relationship between the angles? 1 and? 5 in the respective structural members of the STN-type transflective liquid crystal display device.

8, the alignment direction 81 on the side of the elliptically polarizing plate 1 side of the liquid crystal layer in the liquid crystal cell 8 and the alignment direction 82 on the side of the polarizing plate 9 constitute the angle? 1. The direction 61 of the alignment axis on the side of the polarizing element 4 side of the optical anisotropic element 6 and the direction 62 of the alignment axis on the side of the liquid crystal cell 8 side constitute the angle? 2. The absorption axis 41 of the polarizing element 4 and the angle? 3 with the orientation axis direction 61 on the surface of the optically anisotropic element 6 on the side of the polarizing element 4 constitute an angle? 3 between the absorption axis 41 of the polarization element 4 and the polarization axis of the liquid crystal layer And the alignment direction 81 on the surface on the side of the small 4 constitutes the angle? 4. The absorption axis 91 of the polarizing plate 9 forms an angle? 5 with the absorption axis 41 of the polarizing element 4.

And twisted by? 1 = +240 degrees using ZLI-2293 as a liquid crystal material. The product? Nd of the refractive index anisotropy? N of the liquid crystal material in the liquid crystal cell 8 and the thickness d of the liquid crystal layer was about 830 nm.

The optical anisotropic element 6 was prepared in the same manner as the optical anisotropic element of Example 1. [ The nd of the optical anisotropic element 6 was about 800 nm, and the twist angle was -240 degrees. At this time, the angle? 3 = +45 degrees from the absorption axis 41 of the polarizing element 4 to the alignment axis 61 on the surface of the optically anisotropic element 6 on the polarizing plate side is equal to +45 degrees from the absorption axis 41 of the polarizing element 4 The angle? 4 from the top to the alignment direction 81 was +135 degrees.

(SQW-062, made by Sumitomo Chemical Co., Ltd.) was disposed on the back surface side (lower side of the drawing) of the backlight 10 of the liquid crystal cell 9. The angle? 5 from the absorption axis 41 of the polarizing element 4 to the absorption axis 91 of the polarizing plate 9 was +90 degrees.

A normally transparent adhesive layer was disposed between the elliptically polarizing plate 1 and the liquid crystal cell 8 and the polarizing plate 9.

As a result of examining the optical characteristics at the time of lighting (transmission mode) by arranging the backlight 10 on the liquid crystal display device by applying a driving voltage from the driving circuit (not shown) (1/2 40 duty and optimal bias driving) A contrast indication was obtained. Especially in the transmissive mode.

&Lt; Example 6 >

In Example 3, the produced elliptically polarizing plate H was adhered as an elliptically polarizing plate 1 defined in Fig. 9 on the transparent glass substrate 12 of the organic EL element of the commercial organic EL display 11 via an acrylic adhesive, thereby preparing an organic EL display device . As a result, it was found that an organic EL display device exhibiting a remarkable effect of preventing external light reflection and showing excellent visibility was obtained as compared with the case where the elliptically polarizing plate of the present invention was not disposed.

&Lt; Example 7 >

(Construction of liquid crystalline polymer solution C and laminate P)

100 mmol of 6-hydroxy-2-naphthoic acid, 100 mmol of terephthalic acid, 50 mmol of chlorohydroquinone, 50 mmol of tert-butylcatechol and 600 mmol of acetic anhydride were subjected to acetylation reaction at 140 ° C for 2 hours under a nitrogen atmosphere. Followed by polymerization at 270 ° C for 2 hours, at 280 ° C for 2 hours, and at 300 ° C for 2 hours. The obtained reaction product was dissolved in tetrachloroethane and purified by reprecipitation in methanol to obtain 40.0 g of a liquid crystalline polyester (polymer 1). The liquid crystalline polyester had a logarithmic viscosity of 0.35 (dl / g), a nematic phase as a liquid crystal phase, an isotropic liquid crystal phase transition temperature of 300 占 폚 or higher and a glass transition point of 135 占 폚.

To prepare a? -Butyrolactone solution (liquid crystalline polymer solution C) in which 8 mass% of polymer 1 was dissolved.

A 150 mm diameter rubbing roll with a rayon cloth was installed at an angle while rotating the elongated PEEK film having a width of 650 mm and a thickness of 100 m and rubbed continuously at high speed to obtain an oriented substrate film having a rubbing angle of 45 degrees. Here, the rubbing angle means an angle from the MD direction to the counterclockwise direction when the rubbing surface is viewed from above. The liquid crystalline composition solution C was continuously applied on the orientation substrate film using a die coater and dried, and then the liquid crystalline polymer was oriented by heating at 150 占 폚 for 10 minutes and then cooled to room temperature to fix the orientation, Layer and a PEEK film. The thickness of the obtained layered product P was 0.6 占 퐉.

Since the PEEK film used as the alignment substrate has a large birefringence, it is difficult to measure the optical parameters of the liquid crystalline polymer layer in the form of the layer P, and the liquid crystalline polymer layer is transferred onto the triacetyl cellulose (TAC) film as follows.

That is, an ultraviolet curable adhesive for optics was applied on the liquid crystalline polymer layer on the PEEK film so as to have a thickness of 5 mu m, laminated on a TAC film (40 mu m thick, manufactured by Fuji Photo Film Co., Ltd.) After the adhesive was cured, the PEEK film was peeled off to obtain a laminate composed of the liquid crystal composition layer / adhesive layer / TAC film. The obtained laminate was subjected to parameter measurement with an automatic birefringence system KOBRA21ADH manufactured by Oji Scientific Instruments Co., Ltd. As a result, the liquid crystalline polymer layer formed a hybrid nematic alignment structure, and the nd of the layer was 90 nm, The inclination angle was 28 degrees.

(Construction of elliptically polarizing plate Q)

A commercially available UV curable adhesive (UV-3400, manufactured by Donga Synthetic Co., Ltd.) was applied on the liquid crystalline polymer layer (optically anisotropic element) of the layered product P as an adhesive layer 2 to a thickness of 5 탆, The polarizing element side of the laminate A was laminated, and the adhesive layer 2 was cured by UV irradiation of about 600 mJ. Thereafter, the PEEK film was peeled off from the laminate in which the PEEK film / optical anisotropic element / adhesive layer 2 / polarizing element / adhesive layer 1 / TAC film were integrated, and the optically anisotropic element was transferred onto the laminate A to remove the TAC film / An elliptically polarizing plate Q composed of layer 1 / polarizing element / adhesive layer 2 / optically anisotropic element was obtained. The total thickness of the elliptically polarizing plate Q was 75 탆.

As a result of optical inspection of the elliptically polarizing plate Q, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate Q was adhered to a glass plate via an acrylic adhesive, put in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

&Lt; Example 8 >

(Construction of elliptically polarizing plate R)

In Example 7, a commercially available UV-curable adhesive (UV-3400, manufactured by Donga Synthetic Co., Ltd.) was applied on the optically anisotropic element of the work-restrained laminate P as an adhesive layer 2 with a thickness of 5 탆, The polarizing element side of the laminate F was laminated, and the adhesive layer 2 was cured by UV irradiation of about 600 mJ. Thereafter, the PEEK film was peeled off from the laminate in which the PEEK film / optical anisotropic element / adhesive layer 2 / polarizing element / adhesive layer 1 / Zeonoa film were integrated, and the optically anisotropic element was transferred onto the laminate F, / Adhesive layer 1 / polarizing element / adhesive layer 2 / elliptically polarizing plate R made of an optically anisotropic element. The total thickness of this elliptically polarizing plate R was 75 탆.

As a result of optical inspection of this elliptically polarizing plate R, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate R was adhered to a glass plate through an acrylic pressure-sensitive adhesive, put in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

&Lt; Example 9 >

(Construction of elliptically polarizing plate S)

In Example 2, a 150 mm diameter rubbing roll with a rayon woven fabric was installed at an angle while rotating the small-sized laminate F, and the rubbing was continuously performed by rotating at a high speed to obtain an oriented substrate film having a rubbing angle of 45 degrees. Here, the rubbing angle means an angle from the MD direction to the counterclockwise direction when the rubbing surface is viewed from above. The liquid crystalline composition solution C prepared in Example 7 was continuously applied and dried at a coating rate different from that in Example 7 using a die coater and then heat treated at 150 캜 for 10 minutes to orient the liquid crystalline polymer and then cooled to room temperature To thereby obtain an elliptically polarizing plate S (Zeonoa film / adhesive layer 1 / polarizing element / optical anisotropic element) having optical anisotropic elements composed of a liquid crystalline polymer layer. The total thickness of this elliptically polarizing plate S was 70 탆.

As in Example 7, only the liquid crystalline polymer layer was transferred onto a TAC film and the optical parameters were measured. As a result, the polymer liquid crystal layer formed a hybrid nematic alignment structure, and the ndnd of the polymer liquid crystal layer was 90 nm, Was 28 degrees.

As a result of optical inspection of the elliptically polarizing plate S, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate S was adhered to a glass plate via an acrylic adhesive, placed in a constant temperature and humidity chamber at 60 ° C and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

&Lt; Example 10 >

(Construction of elliptically polarizing plate T)

A 150 mm diameter rubbing roll with a rayon cloth attached thereto was installed obliquely on the surface of the PVA alignment film while rotating the small-layered laminate J in Example 4, and the rubbing was continuously performed by rotating at a high speed to obtain an oriented substrate film with a rubbing angle of 45 did. Here, the rubbing angle means an angle from the MD direction to the counterclockwise direction when the rubbing surface is viewed from above. The liquid crystalline composition solution C prepared in Example 7 was continuously applied and dried in the same manner as in Example 9 using a die coater, and then heat-treated at 150 占 폚 for 10 minutes to align the liquid crystalline polymer. Subsequently, the film was cooled to room temperature to fix the orientation, thereby obtaining an elliptically polarizing plate T (Zeonoa film / adhesive layer 1 / polarizing element / PVA alignment film / optical anisotropic element) having optical anisotropic elements composed of a liquid crystalline polymer layer. The total thickness of this elliptically polarizing plate T was 73 탆.

As a result of optical inspection of the elliptically polarizing plate T, no damage such as spots or scratches was observed. The optically anisotropic element side of the elliptically polarizing plate T was adhered to a glass plate through an acrylic adhesive, put in a constant temperature and humidity chamber at 60 캜 and 90% RH, taken out after 500 hours, and observed. As a result, Not confirmed.

&Lt; Comparative Example 2 &

(Construction of polarizing plate U)

A polarizing plate U was prepared by bonding a saponified TAC film to both sides of a polarizing element in which iodine was adsorbed on stretched polyvinyl alcohol using an acrylic adhesive.

(Construction of laminate V)

In Example 7, the side of the optically anisotropic element of the copying laminate P was transferred to a triacetylcellulose (TAC) film (40 mu m) through an ultraviolet curable adhesive. That is, the adhesive was applied on the liquid crystalline polymer layer on the PEEK film so as to have a thickness of 5 탆, laminated on the TAC film, and the adhesive was cured by irradiating ultraviolet rays from the TAC film side, (Optical anisotropic element / adhesive layer / TAC film).

(Construction of elliptically polarizing plate W)

An optically anisotropic element side of the laminate V was bonded to the polarizing plate U via an acrylic pressure-sensitive adhesive to form an elliptically polarizing plate W. The elliptically polarizing plate W had a thick thickness of about 200 탆 and the winding thickness was increased, so that the processing length in one operation could not be shorter than that of the elliptically polarizing plates of Examples 7 to 10.

An acrylic pressure-sensitive adhesive was applied to the optically anisotropic element side of the elliptically polarizing plate W and adhered to a glass plate. As a result of performing the same test as in Example 7, peeling of 0.5 mm at the end was observed after 500 hours passed.

&Lt; Example 11 >

Using the elliptically polarizing plate Q obtained in Example 7, a transmissive liquid crystal display device was constructed as shown in Fig.

The used liquid crystal cell 8 was homogeneously oriented by using ZLI-1695 (Merck) as a liquid crystal material. The thickness of the liquid crystal layer was 4.9 mu m, the angle of the pretilt at both interfaces of the substrates of the liquid crystal layer was 2 degrees, and DELTA nd of the liquid crystal cell was about 320 nm.

(SQW-062, manufactured by Sumitomo Chemical Co., Ltd.) was placed on the observer side (upper side of the figure) of the liquid crystal cell 8, and a polycarbonate uniaxially stretched between the polarizing plate 9 and the liquid crystal cell 8 Retardation compensation plate 16 made of a film (made by Nippon Zeon Co., Ltd., nd is about 140 nm) was disposed.

The absorption axis of the polarizing plate 9 and the polarizing element 4, the slow axis of the phase difference compensating plate 16, the linear inclining direction of both interfaces of the liquid crystal cell 7, and the slanting direction of the optically anisotropic element 6 were arranged under the conditions described in FIG. A backlight 10 is provided on the back surface side of the elliptically polarizing plate 1.

The optical characteristics of the liquid crystal display device at the time of lighting (transmission mode) were examined by applying a driving voltage from 0 V to 5 V from the driving circuit (not shown) and disposing the backlight 10. As a result, clear and high contrast and viewing angle dependency It was found that few characteristics were obtained.

1 is a conceptual diagram for explaining the inclination angle and the twist angle of liquid crystal molecules.

2 is a conceptual diagram of an alignment structure of a liquid crystalline film constituting an optically anisotropic element.

3 is a conceptual diagram for explaining the line oblique direction of the liquid crystal cell.

4 is a cross-sectional elevation view schematically showing a configuration example of the elliptically polarizing plate of the present invention.

5 is a cross-sectional elevation view schematically showing another configuration example of the elliptically polarizing plate of the present invention.

6 is a cross-sectional elevation view schematically showing another configuration example of the elliptically polarizing plate of the present invention.

7 is a conceptual diagram of a liquid crystal display device used in the fifth embodiment.

8 is a plan view for explaining the axis angle relationship between the absorption axis of the polarizing plate and the liquid crystal cell and the optically anisotropic layer in the liquid crystal display device of Example 5. Fig.

Fig. 9 is a conceptual diagram of an organic EL display used in Embodiment 6; Fig.

10 is a conceptual diagram of a liquid crystal display used in Example 11. Fig.

11 is a plan view for explaining the axis angle relationship between the absorption axis of the polarizing plate and the liquid crystal cell and the optically anisotropic layer in the liquid crystal display device of Example 11. Fig.

(Explanation of Symbols)

The present invention relates to a polarizing plate and a polarizing plate, and more particularly, to an optical polarizing plate, a liquid crystal cell, and a polarizing plate, A polarizing element 4 on the observer side, 61 an optical anisotropic element 6, and a polarizing element 6 on the observer side. 81: orientation axis of the optically anisotropic layer 6 on the side of the liquid crystal cell 8, 81: orientation direction of the liquid crystal layer in the liquid crystal cell 8 on the side of the polarization element 4 side, 82: Direction of the layer on the backlight 10 side, 91: absorption axis of the polarizing plate 9

Claims (24)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete (1) a first step of obtaining a laminate (A) composed of a light-transmitting protective film / adhesive layer 1 / polarizing element by adhering a light-transmitting protective film to a polarizing element via an adhesive layer 1, and (2) The surface of the polarizing element of the layered product (A) is subjected to a rubbing treatment to form a layer composed of a liquid crystalline composition exhibiting at least positive uniaxial property on the polarizing element, and this layer is subjected to twisted nematic orientation or hybrid Nematic A second step of obtaining an elliptically polarizing plate composed of a light-transmitting protective film / adhesive layer 1 / polarizing element / optical anisotropic element by forming an optically anisotropic element by immobilizing said composition in this orientation after tick orientation Wherein the elliptically polarizing plate is a elliptically polarizing plate. The method for producing an elliptically polarizing plate according to claim 16, wherein an alignment film forming a nematic alignment of the liquid crystal composition exhibiting at least positive uniaxial property is disposed on the polarizing element, and then rubbing treatment is performed. The method for producing an elliptically polarizing plate according to claim 16 or 17, wherein the light-transmitting protective film is triacetyl cellulose or cycloolefin-based polymer. The method for producing an elliptically polarizing plate according to claim 16 or 17, wherein the light-transmitting protective film is surface-treated. The method of manufacturing an elliptically polarizing plate according to claim 16 or 17, wherein the surface treatment is a saponification treatment or a corona discharge treatment. The method for producing an elliptically polarizing plate according to claim 16 or 17, wherein the polarizing element is surface-treated. The method of manufacturing an elliptically polarizing plate according to claim 21, wherein the surface treatment is a corona discharge treatment. delete delete

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