JP2006171623A - Liquid crystal display - Google Patents

Abstract

[PROBLEMS] To prevent scattering of light from the rear without deteriorating the image characteristics from the front direction, preventing a decrease in screen contrast, and preventing reflection on the screen from any direction. Another object is to provide a reflective and / or transflective liquid crystal display device.
A liquid crystal display device in which a polarizing plate, an optical anisotropic body, and a liquid crystal cell are laminated, wherein the retardation value [Re (550)] of the optical anisotropic body measured at a wavelength of 550 nm and a wavelength of 450 nm. The ratio Re (450) / Re (550) to the retardation value [Re (450)] measured in Step 1 is 1.007 or less, and an antireflection laminate is formed on the outermost surface on the light incident side of the liquid crystal display device. A reflective or transflective liquid crystal display device having a low refractive index layer composed of aerogel and having a refractive index of 1.37 or less.
[Selection figure] None.

Description

  The present invention relates to a reflective or transflective liquid crystal display device. More specifically, the present invention is excellent in antireflection and scratch resistance, prevents deterioration in contrast when the screen is viewed from an oblique direction without deteriorating image characteristics from the front direction, and is viewed from any direction. The present invention also relates to a reflective or transflective liquid crystal display device having good black display quality and having a uniform and high contrast.

  In recent years, the liquid crystal display device is expected to expand the market as a display of a portable information terminal device that can make the most of its thin and light features. Since portable electronic devices are usually battery-driven, it is an important issue to reduce power consumption. Therefore, as a liquid crystal display device for portable use, a transflective or reflective liquid crystal display device that does not use a backlight that consumes a large amount of power, or is a low power consumption type that is not always used, and is thin and lightweight, is particularly noted. Has been.

  Since the reflective liquid crystal display device uses external light incident from the display surface, it has a drawback that the display becomes difficult to see when used in a dark environment. As a technique for solving this problem, in a reflection type liquid crystal display device with a single polarizing plate, a transflective plate having a property of transmitting a part of incident light is used instead of a reflecting plate, and a backlight is used. A transflective liquid crystal display device provided has been proposed. In this case, the backlight can be used as a reflection type (reflection mode) using external light, and in a dark environment, the backlight can be used as a transmission type (transmission mode).

Reflective liquid crystal display devices are also required to have color, high definition, and high display quality, which can efficiently capture light and improve brightness, and can improve contrast by eliminating white blur caused by light leakage. It is mandatory. However, even if these improvements are made, a part of the light incident from the outside is reflected on the surface of the display device, and the display screen glare, and the display quality is inevitably lowered due to reflection. As a method for preventing this surface reflection, an antiglare treatment or an antireflection treatment has been performed. As a specific example of the antireflection means, an antireflection layer composed of a plurality of inorganic oxides has been reported (Patent Documents 1 and 2). However, this antireflection layer cannot prevent sufficient light reflection. Furthermore, it is reported that this antireflection layer is combined with a convex antiglare layer (Patent Document 3). However, the convex shape of the antiglare layer causes backward light scattering, which may affect the contrast.
JP 2000-47187 A JP 2001-74910 A JP 2002-318383 A

  The present invention not only deteriorates the image characteristics from the front direction, but also prevents the scattering of light from the rear and prevents the contrast of the screen from being lowered, and also reflects on the screen from any direction. It is to provide a reflective or transflective liquid crystal display device that prevents.

  The present inventors are a liquid crystal display device having an output-side polarizer, an optical anisotropic body, and a liquid crystal cell, wherein the optical anisotropic body has an in-plane retardation value [Re (550)] measured at a wavelength of 550 nm. The ratio Re (450) / Re (550) to the in-plane retardation value [Re (450)] measured at a wavelength of 450 nm is 1.007 or less, and the airgel on the far side from the liquid crystal cell of the exit side polarizer By constructing a reflective or transflective liquid crystal display device comprising an antireflection laminate comprising a low refractive index layer having a refractive index of 1.37 or less, the screen can be viewed from any direction. It has been found that the image is not reflected on the screen, has a uniform and high contrast, and has an excellent antireflection effect. Based on this finding, the present invention has been completed.

  The reflective or transflective liquid crystal display device of the present invention has an optical anisotropic body having specific in-plane retardation characteristics, and a low refractive index layer made of airgel provided on the side far from the liquid crystal cell of the exit side polarizer. By combining with the antireflection laminate, the viewing angle is wide, there is no reflection, the scratch resistance is excellent, the black display quality is good from any direction, and it has a uniform and high contrast. The liquid crystal display device of the present invention can be suitably used as a display for a portable information terminal such as a personal computer, a cellular phone, a portable video game machine, and an electronic notebook.

  The reflective or transflective liquid crystal display device of the present invention includes an exit-side polarizer, an optical anisotropic body, and a liquid crystal cell, and the optical anisotropic body has an in-plane retardation value [Re ( 550)] and the in-plane retardation value [Re (450)] measured at a wavelength of 450 nm, Re (450) / Re (550) is 1.007 or less, which is far from the liquid crystal cell of the exit side polarizer. On the side, an antireflection laminate having a low refractive index layer composed of aerogel and having a refractive index of 1.37 or less is provided.

The liquid crystal cell constituting the liquid crystal display device of the present invention is obtained by encapsulating a liquid crystalline compound between a transparent electrode substrate having no reflection function and a transparent electrode substrate having a reflection function over the entire surface or a part thereof. When a substrate having a reflective function is used over the entire surface, a reflective liquid crystal display device can be obtained, and when a substrate having a reflective function is used in part, a transflective liquid crystal display device can be obtained.
A reflector is usually used to provide a reflection function. A metal plate is preferable as the reflecting plate. If the surface of the reflecting plate is smooth, only the regular reflection component may be reflected and the viewing angle may be narrowed. Therefore, it is preferable to introduce a concavo-convex structure (see Japanese Patent No. 2756206) on the surface of the reflector. Further, in the case of a transflective liquid crystal display device, it can be composed of a region that transmits light and a region that reflects light.

  The liquid crystal cell used in the present invention is not particularly limited depending on the kind of liquid crystal compound to be encapsulated, the method of operating the liquid crystal compound, and the like. For example, the TN (Twisted Nematic) method, STN (SuperTwisted Nematic) method, ECB ( There are an Electrically Controlled Birefringence (IPS) method, an IPS (In-Plane Switching) method, a VA (Vertical Alignment) method, an OCB (Optically Compensated Birefringence) method, a HAN (Hybrid Aligned Nematic) method, an ASM (Axially Symmetric Aligned Microcell) method, and the like. Further, there are various methods such as a halftone gray scale method, a domain division method, a display method using a ferroelectric liquid crystal and an antiferroelectric liquid crystal.

The exit-side polarizer used in the present invention can extract linearly polarized light from natural light. For example, there are an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film. The thickness of the polarizer is not particularly limited, but it is usually preferable to use a polarizer having a thickness of 5 to 80 μm. The exit side polarizer is usually provided on the transparent electrode substrate side that does not have a reflection function of the liquid crystal cell.
In the transflective liquid crystal device, an incident-side polarizer is further provided on the transparent electrode substrate side having a reflection function of the liquid crystal cell, and the liquid crystal cell is disposed between the output-side polarizer and the incident-side polarizer. The incident side polarizer has the same function and configuration as the exit side polarizer. In the transflective liquid crystal device, the transmission axis of the exit side polarizer and the transmission axis of the entrance side polarizer are preferably arranged so as to be substantially perpendicular.

  The optical anisotropic body used in the present invention has a ratio Re (450) / in-plane retardation value [Re (550)] measured at a wavelength of 550 nm and in-plane retardation value [Re (450)] measured at a wavelength of 450 nm. Re (550) is 1.007 or less, preferably 1.006 or less. The lower limit of the ratio Re (450) / Re (550) is preferably 0.5, more preferably 0.7. By providing an optical anisotropic body in which Re (450) / Re (550) falls within the above range, a color display with good color development can be obtained. Retardation includes film in-plane retardation (Re) and film thickness direction retardation (Rth). Retardation (Re) in the film plane can be obtained by Re = (nx−ny) × d, where the main refractive index in the film plane is nx and ny, and the film thickness is d (nm). . Retardation (Rth) in the film thickness direction is defined as follows: Rx = {ny} where ny is the main refractive index in the film plane, nz is the refractive index in the film thickness direction, and d (nm) is the film thickness. (Nx + ny) / 2−nz} × d. Re and Rth can be measured using a commercially available automatic birefringence meter (“KOBRA-21ADH” manufactured by Oji Scientific Instruments).

The optical anisotropic body used in the present invention preferably has an in-plane retardation Re (550) measured at a wavelength of 550 nm of 125 to 150 nm.
In the optical anisotropic body used in the present invention, the ratio Re (λ) / λ of the retardation Re (λ) at the wavelength λ is usually 0.22 to 0.28, preferably 0.23 to 0.23. It is preferably 0.27, more preferably in the range of 0.24 to 0.26.

The optical anisotropic body used in the present invention is not particularly limited even if it has a single layer structure and a laminated structure as long as it has the above characteristics. For example, a suitable optical anisotropic body includes an optical anisotropic body in which a quarter-wave plate and a half-wave plate are overlapped with each other along the slow axis direction.
Here, the quarter-wave plate is an optical anisotropic body having a retardation measured at a wavelength of 550 nm of 125 to 150 nm. The half-wave plate is an optically anisotropic body having a retardation measured at a wavelength of 550 nm and 250 to 300 nm.

(I) A quarter wavelength plate and a half wavelength plate can be obtained by stretching and orienting a transparent resin film.
The slow axis of the optical anisotropic body usually occurs in the stretching direction or a direction perpendicular thereto. The slow axis crossing angle of the quarter-wave plate and half-wave plate obtained by stretching the transparent resin is preferably 56 ° to 62 °, more preferably 57 ° to 61 °. When the slow axis crossing angle is in the above range, an optical anisotropic body excellent in broadband property can be obtained. The slow axis is the direction in which the phase delay becomes maximum when linearly polarized light is incident.

The transparent resin constituting the film can be used without particular limitation as long as it is a resin having a total light transmittance of 80% or more when formed into a 1 mm-thick molded body.
Specific examples of the transparent resin include a polymer resin having an alicyclic structure, a chain olefin polymer such as polyethylene and polypropylene, a polycarbonate polymer, a polyester polymer, a polysulfone polymer, and a polyethersulfone polymer. Resin having positive intrinsic birefringence such as polymer, polyvinyl alcohol polymer; negative intrinsic birefringence such as vinyl aromatic polymer, polyacrylonitrile polymer, polymethyl methacrylate polymer, cellulose ester polymer, etc. A resin having refraction can be mentioned. These can be used in combination of two or singly.

Among the resins having positive intrinsic birefringence, polymer resins and chain olefin polymers having an alicyclic structure are preferable, and particularly excellent in transparency, low hygroscopicity, dimensional stability, light weight, etc. A polymer resin having a cyclic structure is preferred.
Examples of the polymer having an alicyclic structure include a norbornene polymer, a monocyclic olefin polymer, and a vinyl alicyclic hydrocarbon polymer. Among these, norbornene-based polymers can be suitably used because they have good transparency and moldability. Examples of the norbornene-based polymer include a ring-opening polymer of a norbornene-based monomer, a ring-opening copolymer of a norbornene-based monomer and another monomer, and a hydrogenated product of these polymers; Examples include addition polymers of monomers, addition copolymers of norbornene monomers and other monomers, and hydrogenated products of these polymers. Among these, a hydrogenated product of a ring-opening polymer or a ring-opening copolymer of a norbornene monomer is particularly preferable because it is excellent in transparency.

Among the resins having negative intrinsic birefringence, at least one selected from vinyl aromatic polymers, polyacrylonitrile polymers, and polymethyl methacrylate polymers is preferable. Of these, vinyl aromatic polymers are more preferable from the viewpoint of high birefringence.
The vinyl aromatic polymer refers to a polymer of a vinyl aromatic monomer or a copolymer of a monomer copolymerizable with a vinyl aromatic monomer. Examples of the vinyl aromatic monomer include styrene; styrene derivatives such as 4-methylstyrene, 4-chlorostyrene, 3-methylstyrene, 4-methoxystyrene, 4-tert-butoxystyrene, α-methylstyrene, and the like. It is done. These may be used alone or in combination of two or more. Monomers copolymerizable with vinyl aromatic monomers include olefins such as propylene and butene; α, β-ethylenically unsaturated nitrile monomers such as acrylonitrile; acrylic acid, methacrylic acid, maleic anhydride, etc. Α, β-ethylenically unsaturated carboxylic acid; acrylic acid ester, methacrylic acid ester; maleimide; vinyl acetate; vinyl chloride; Among vinyl aromatic polymers, a copolymer of styrene or a styrene derivative and maleic anhydride is preferable from the viewpoint of high heat resistance.

  The transparent resin used in the present invention preferably has a glass transition temperature Tg of 90 ° C. or higher, particularly preferably 100 ° C. or higher, from the viewpoint of excellent heat resistance.

  The formation method in particular of the said transparent resin film is not restrict | limited, For example, conventionally well-known methods, such as a solution casting method and a melt extrusion method, are mentioned. Among them, the melt extrusion method that does not use a solvent can reduce the content of volatile components, is easy to produce a film having a large Rth of 100 μm or more, and is preferable from the viewpoint of manufacturing cost. Examples of the melt extrusion method include a method using a die, an inflation method, and the like, but a method using a T die is preferable because it is excellent in productivity and thickness accuracy.

  In the method for producing a film using a T die, the transparent resin is put into an extruder having a T die, and is usually 80 to 180 ° C. higher than the glass transition temperature of the transparent resin, preferably higher than the glass transition temperature. The transparent resin is melted at a temperature higher by 100 to 150 ° C., the molten resin is extruded from a T die, and the resin is cooled with a cooling roll or the like to form a film. If the melting temperature of the resin is excessively low, the fluidity of the transparent resin may be insufficient, and conversely if excessively high, the transparent resin may deteriorate.

  There is no particular restriction on the stretching method, for example, a uniaxial stretching method such as a method of uniaxial stretching in the longitudinal direction using a difference in peripheral speed between rolls, a method of uniaxial stretching in the transverse direction using a tenter; Simultaneous biaxial stretching method in which the gap between the clips to be opened is expanded in the longitudinal direction at the same time as the longitudinal direction of the guide rail, and the both ends after stretching in the longitudinal direction using the difference in peripheral speed between the rolls. Biaxial stretching method such as sequential biaxial stretching method in which a clip is held by a clip and stretched in the transverse direction using a tenter; Tenter stretching that can add feeding force, pulling force, or pulling force at different speeds in the lateral or longitudinal direction Machine, horizontal or vertical feed force, pulling force or pulling force at the same speed can be added, and the moving distance can be the same and the stretching angle can be fixed or the moving distance can be different. How to oblique stretching using a coater stretcher; and the like.

The retardation of the optical anisotropic body can be controlled, for example, by appropriately setting the stretching conditions such as the film material, the thickness of the film before stretching, the stretching ratio and the stretching temperature.
When the glass transition temperature of the transparent resin is Tg, the stretching of the film is preferably in a temperature range of Tg-30 ° C to Tg + 60 ° C, more preferably in a temperature range of Tg-10 ° C to Tg + 50 ° C, preferably It is carried out at a draw ratio of 1.01 to 2 times. The stretching speed is preferably 5 to 1000 mm / second, more preferably 10 to 750 mm / second. When the stretching speed is within the above range, stretching control is facilitated, and an optical anisotropic body with small variations in surface accuracy and retardation can be obtained.

  The refractive index nz in the thickness direction of the optical anisotropic body used in the present invention is not particularly limited. For example, nz and other main refractive indexes nx and ny have a relationship of nx> ny> nz, nx> ny = nz, nx> nz> ny, nx = nz> ny, nz> nx> ny. Can be mentioned.

  The optical anisotropic body has a thickness of preferably 10 to 500 μm, more preferably 20 to 250 μm, and particularly preferably 20 to 120 μm.

(Ii) The quarter wavelength plate and the half wavelength plate can also be obtained by aligning and fixing a liquid crystal compound.
The liquid crystalline compound has optical anisotropy, and a film having optical anisotropy can be obtained by arranging and fixing the liquid crystalline compound in a certain direction. Specifically, a low molecular weight or high molecular weight liquid crystalline compound having a property of being polymerized or crosslinked by ultraviolet rays or heat in the presence of a polymerization initiator or a crosslinking agent, or a mixture thereof was aligned substantially uniformly. It can be obtained by immobilization by polymerization or crosslinking reaction.

Examples of the liquid crystalline compound used for obtaining the optical anisotropic body include a rod-like liquid crystalline compound, a discotic liquid crystalline compound, or a mixture thereof.
Examples of rod-like liquid crystalline compounds include azomethines, azoquinones, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, tolanes, cyano-substituted phenylpyrimidines, alkoxy-substituted compounds Examples include phenylpyrimidines, phenyldioxanes, alkenylcyclohexylbenzonitriles and the like. Moreover, not only the low molecular liquid crystalline compound as described above but also a polymer rod-shaped liquid crystalline compound can be used. Furthermore, specific examples of the rod-like liquid crystalline compound include polymerizable liquid compositions described in JP-A-7-294735, JP-A-2002-174724, and JP-A-8-283748. As an example of an optical anisotropic body using a rod-like liquid crystalline compound, a film in which liquid crystal is vertically aligned and showing a relationship of nz> nx≈ny shows a relationship of nz>nx> ny in a film having a tilted orientation. Things can be raised. Commercially available products such as a trade name NH film (manufactured by Nippon Oil Co., Ltd.) can be used as the tilted film.

  As the discotic liquid crystalline compound, various documents (for example, C. Desradade et al., Mol. Crysr. Liq. Cryst., Vol. 71, page 111 (1981); edited by the Chemical Society of Japan, Quarterly Chemical Review, No. .22, Liquid Crystal Chemistry, Chapter 5, Chapter 10, Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm. Page 1794 (1985); J. Zhang et al., J. Am. Chem. Soc., Vol. 116, page 2655 (1994); The polymerization of discotic liquid crystalline compounds is described in JP-A-8-27284. In order to fix the discotic liquid crystalline compound by polymerization, it is necessary to bond a polymerizable group to the discotic core of the discotic liquid crystalline compound via a linking group. Examples of such discotic liquid crystalline compounds include those described in JP-A No. 2000-284126. Commercially available products such as a trade name WV film (manufactured by Fuji Photo) may be used as an optical anisotropic body using a discotic liquid crystalline compound.

The alignment of the liquid crystalline compound can usually be performed by applying the liquid crystalline compound to the alignment film.
The alignment film is usually formed of a polymer compound having optical isotropy. Specifically, cellulose resin, polyimide, polyimide amide, polyether imide, polyester, polyarylate, polyvinyl alcohol, gelatin and the like can be mentioned. You may use these in combination of 2 or more types.
When a discotic liquid crystal is used as the liquid crystalline compound, the discotic liquid crystal molecules are aligned substantially perpendicularly to the plane direction of the film or laminate (average tilt angle in the range of 50 to 90 degrees). Is preferred. For this purpose, the surface energy of the alignment film is lowered by the functional group of the polymer constituting the alignment film, thereby bringing the discotic liquid crystalline compound into a standing state. Preferred examples of the functional group that lowers the surface energy of the alignment film include fluorine atoms and hydrocarbon groups having 10 or more carbon atoms. In order to allow fluorine atoms or hydrocarbon groups to be present on the surface of the alignment film, it is preferable to introduce fluorine atoms or hydrocarbon groups into the side chain rather than the main chain of the polymer. The fluorine atom content of the polymer containing fluorine atoms is preferably 0.05 to 80% by weight, more preferably 0.5 to 65% by weight, and still more preferably 1 to 60% by weight. Examples of the hydrocarbon group include aliphatic groups, aromatic groups, and combinations thereof. The aliphatic group may be cyclic, branched or linear, but is preferably an alkyl group, a cycloalkyl group, an alkenyl group or a cycloalkenyl group. The number of carbon atoms of the hydrocarbon group is preferably 10 to 100, more preferably 10 to 50, still more preferably 10 to 40. The main chain of such a polymer preferably has a polyimide structure or a polyvinyl alcohol structure. Polyimide can generally be synthesized by a condensation reaction of tetracarboxylic acid and diamine. When introducing a hydrocarbon group into polyimide, it is preferable to form a steroid structure in the main chain or side chain of the polyimide. The steroid structure present in the side chain corresponds to a hydrocarbon group having 10 or more carbon atoms, and has a function of vertically aligning the discotic liquid crystalline compound. Examples of the polyvinyl alcohol include fluorine-modified polyvinyl alcohol containing a repeating unit containing a fluorine atom in a range of 5 to 80 mol, and modified polyvinyl alcohol having a hydrocarbon group having 10 or more carbon atoms.

  In order to form an alignment film, the polymer compound is formed, and the alignment treatment is performed on the polymer film. A rubbing process is preferably used as the alignment process. The method for rubbing the polymer film is not particularly limited, and can be performed by a conventionally known method. For example, a method of imparting orientation to the surface of the polymer film by rubbing the surface of the polymer film in a predetermined direction (rubbing) using a cloth or roll such as rayon or nylon can be mentioned. Examples of the alignment treatment other than the rubbing treatment include a method of irradiating light such as linearly polarized ultraviolet light on the polymer film from a predetermined direction, a method of stretching the polymer film, and the like. In addition to the polymer film, an oblique deposition layer such as silicon oxide (SiO2) can be used as the alignment film. The thickness of the alignment film is usually 0.005 to 10 μm, preferably 0.01 to 1 μm.

On an optical anisotropic body such as a quarter-wave plate or a half-wave plate, an alignment film that has been subjected to an alignment treatment in a direction in which the angle formed with the slow axis of the optical anisotropic body is 50 to 70 degrees. The liquid crystal compound fixed film (corresponding to a half-wave plate) whose retardation measured at a wavelength of 550 nm is 250 to 300 nm or the retardation measured at a wavelength of 550 nm is 125 to 150 nm. By forming a fixed film (corresponding to a quarter-wave plate) of a liquid crystal compound, an optical anisotropic body corresponding to a superposition of a quarter-wave plate and a half-wave plate can be obtained. .
The direction of the alignment treatment intersects with the direction of the slow axis of the optical anisotropic body serving as the substrate in the range of 50 to 70 degrees, preferably 55 to 65 degrees, more preferably 58 to 62 degrees. . The liquid crystalline compound applied on the alignment film is aligned in a direction that coincides with the alignment direction of the alignment film. Therefore, by performing the alignment treatment at the angle as described above, a laminated body in which the slow axis of the optical anisotropic body of the substrate and the optical anisotropic body formed of the liquid crystalline compound intersect at a predetermined angle is obtained. be able to.

  The thickness of the optically anisotropic layer composed of the alignment-fixed film of the liquid crystalline compound is not particularly limited, but provides a sufficient function as a quarter-wave plate that gives a quarter-wave retardation to incident light. Above, it is preferable that it is 0.5-50 micrometers normally. By setting the type of the liquid crystal compound immobilization film and the thickness of the liquid crystal compound immobilization film layer to a predetermined one, a quarter wavelength plate composed of the liquid crystal compound immobilization film layer can be obtained. it can.

  In order to form an optical anisotropic body composed of a fixed film of a liquid crystal compound, specifically, it can be carried out as follows. First, on the optical anisotropic body, an alignment film is formed that is aligned in a direction in which an angle between the extending direction of the optical anisotropic body and the slow axis of the optical anisotropic body is 50 to 70 degrees. Next, an organic solvent solution of a liquid crystalline compound is applied onto the alignment film of the optical anisotropic body, and the solvent is removed by heating. Next, the liquid crystalline compound can be aligned in a predetermined direction by cooling to a temperature at which the liquid crystalline compound is in a liquid crystal state. Further, when the liquid crystalline compound is polymerized or crosslinked by ultraviolet rays or heat, the liquid crystalline compound is polymerized or crosslinked by ultraviolet rays or heat in the presence of a polymerization initiator or a crosslinking agent in an environment where the liquid crystal state is maintained. A compound-immobilized film can be formed.

  The method of laminating a quarter-wave plate and a half-wave plate is a method of laminating a wave plate, such as a method of laminating with an adhesive, a method of laminating by thermal welding or ultrasonic fusion, or a coextrusion method. A known method can be used, but it is preferable to laminate using an adhesive in order to use it in a wider wavelength region as a broadband wavelength plate and to have excellent durability.

  In the liquid crystal display device of the present invention, for the purpose of widening the viewing angle, in addition to the optical anisotropic body, other films having optical anisotropy are arranged in an arbitrary number and in arbitrary locations. Can do. Examples of the film having optical anisotropy include a uniaxial retardation film, a biaxial retardation film, and a laminate thereof. For example, examples of the uniaxial retardation plate include a C plate and an A plate.

The C plate is a retardation layer having no retardation or very small in-plane retardation and having a retardation only in the thickness direction, and an optical axis exists in a thickness direction perpendicular to the in-plane direction. The C plate is referred to as a positive C plate when its optical characteristic condition satisfies the following formula (1), and is referred to as a negative C plate when the following formula (2) is satisfied.
The following nx, ny, and nz represent the refractive indexes in the X-axis, Y-axis, and Z-axis directions in the retardation plate or the like, and the X-axis direction has the maximum refractive index in the plane of the layer. Direction (in-plane slow axis direction), and the Y-axis direction is a direction (in-plane fast axis direction) perpendicular to the X-axis direction in the plane of the layer, and the Z-axis direction is , The thickness direction of the layer perpendicular to the X-axis direction and the Y-axis direction.
nx≈ny <nz (1)
nx≈ny> nz (2)

The A plate is a retardation layer having no or very small retardation in the thickness direction and having retardation only in the plane, and the optical axis exists in the in-plane direction. The A plate is called a positive A plate when its optical characteristics satisfy the following formula (3), and is called a negative A plate when the following formula (4) is satisfied.
nx> ny≈nz (3)
nx≈nz> ny (4)
Examples of the biaxial retardation plate include a positive biaxial retardation plate (nz>nx> ny) and a negative biaxial retardation plate (nx>ny> nz).
As a retardation plate having uniaxiality or a retardation plate having biaxiality, a film obtained by stretching a film made of a material having a positive intrinsic birefringence value, a material having a negative intrinsic birefringence value such as a polystyrene resin, etc. A layered product in which layers made of a material having a positive intrinsic birefringence, such as norbornene-based resin, are stretched on both sides of the layer, or a discotic liquid crystal aligned in parallel or perpendicularly to the surface. Can be mentioned.
The in-plane retardation Re of the layer exhibiting birefringence and Rth which is the retardation perpendicular to the surface may be appropriately adjusted according to the liquid crystal mode to be used.

  In the liquid crystal display device of the present invention, an antireflection laminate is provided on the side (viewing side) far from the liquid crystal cell of the output side polarizer. This antireflection laminate has a low refractive index layer composed of aerogel and having a refractive index of 1.37 or less. Preferably, the hard coat layer and the low refractive index layer are directed away from the liquid crystal cell. It has in this order.

  The hard coat layer is a layer having a high surface hardness. Specifically, it is a layer having a hardness of “HB” or higher in the pencil hardness test specified in JIS K5600-5-4. Although the average thickness of a hard-coat layer is not specifically limited, Usually, it is 0.5-30 micrometers, Preferably it is 3-15 micrometers. The material for forming the hard coat layer may be any material that can form a layer having a pencil hardness specified in JIS K 5600-5-4 having a hardness of HB or higher. For example, silicone, melamine, epoxy, Examples thereof include organic hard coat materials such as acrylic and urethane acrylate; inorganic hard coat materials such as silicon dioxide; Among these, urethane acrylate-based and polyfunctional acrylate-based hard coat materials can be preferably used because of their high adhesive strength and excellent productivity.

  The refractive index of the hard coat layer is preferably 1.55 or more, and more preferably 1.60 or more. When the refractive index of the hard coat layer is 1.55 or more, the antireflection performance and scratch resistance in a wide band are improved, and the design of the low refractive index layer laminated on the hard coat layer becomes easy. The refractive index can be measured and determined using, for example, a known spectroscopic ellipsometer.

  The hard coat layer preferably further contains inorganic oxide particles. By adding inorganic oxide particles, a hard coat layer having excellent scratch resistance and a refractive index of 1.55 or more can be easily formed. As an inorganic oxide particle used for a hard-coat layer, a thing with a high refractive index is preferable. Specifically, inorganic oxide particles having a refractive index of 1.6 or more, particularly 1.6 to 2.3 are preferable. Examples of such inorganic oxide particles having a high refractive index include titania (titanium oxide), zirconia (zirconium oxide), zinc oxide, tin oxide, cerium oxide, antimony pentoxide, and antimony-doped tin oxide (ATO). Phosphorus-doped tin oxide (PTO), fluorine-doped tin oxide (FTO), tin-doped indium oxide (ITO), zinc-doped indium oxide (IZO), aluminum-doped zinc oxide (AZO) , Etc. Among these, antimony pentoxide is suitable as a component for adjusting the refractive index because it has a high refractive index and an excellent balance between conductivity and transparency.

A hard-coat layer is obtained by apply | coating the said hard-coat material to a transparent resin base material, drying and hardening. Before applying the hard coat material, plasma treatment, primer treatment, or the like can be applied to the surface of the substrate to increase the peel strength of the hard coat layer. As a curing method, there are a thermal curing method and an ultraviolet curing method. In the present invention, the ultraviolet curing method is preferable.
In addition, the substrate resin and the hard coat layer material are co-extruded to form a co-extruded film in which the substrate resin and the hard coat material are laminated. The thing of the structure which laminated | stacked the coating layer can be obtained.
The hard coat layer may have a concavo-convex shape formed on its surface in order to impart antiglare properties. The uneven shape is not particularly limited as long as it is a shape effective for imparting a known antiglare property.

The low refractive index layer has a refractive index of 1.37 or less. Preferably it is 1.37 to 1.25, more preferably 1.36 to 1.32. By providing this low refractive index layer, a liquid crystal display device having an excellent balance between visibility, scratch resistance and strength, and an excellent balance between antireflection performance and scratch resistance can be obtained. The thickness of the low refractive index layer is preferably 10 to 1,000 nm, and more preferably 30 to 500 nm.
The low refractive index layer is made of airgel. The airgel is a transparent porous body in which minute bubbles are dispersed in a matrix, and the diameter of the bubbles is mostly 200 nm or less. The content of air bubbles in the airgel is preferably 10 to 60% by volume, and more preferably 20 to 40% by volume. Examples of the airgel include silica aerogel and a porous body in which hollow particles are dispersed in a matrix.

  Silica airgel is a wet gel material consisting of a silica skeleton obtained by the hydrolysis polymerization reaction of alkoxysilane, in the presence of a solvent or dispersion medium such as alcohol or carbon dioxide, which is above the critical point of the solvent or dispersion medium. It can be produced by drying in a supercritical state. In supercritical drying, for example, a gel substance is immersed in liquefied carbon dioxide, and all or a part of the solvent contained in the gel substance is replaced with liquefied carbon dioxide having a lower critical point than that of the solvent. It can carry out by drying under supercritical conditions of a single system or a mixed system of carbon dioxide and a solvent. Silica airgel can also be produced in the same manner as described above using sodium silicate as a raw material. The refractive index of silica airgel can be freely changed according to the raw material mixing ratio of the airgel.

As another embodiment, the porous body in which hollow particles are dispersed in a matrix is a porous body in which hollow fine particles having voids inside fine particles are dispersed in a binder resin. The binder resin is made of polyester resin, acrylic resin, urethane resin, vinyl chloride resin, epoxy resin, melamine resin, so as to meet the conditions such as dispersibility of hollow fine particles, transparency of the porous body, and strength of the porous body. Fluorine resin, silicone resin, butyral resin, phenol resin, vinyl acetate resin, UV curable resin, electron beam curable resin, emulsion resin, water-soluble resin, hydrophilic resin, mixture of these resins, and modified products of these resins And a hydrolyzable organic silicon compound such as alkoxysilane and a hydrolyzate thereof. Among these, hydrolyzable organosilicon compounds such as acrylic resins, epoxy resins, urethane resins, silicone resins, alkoxysilanes, and hydrolysates thereof have good fine particle dispersibility and high strength of the porous body. Therefore, it can be preferably used.
The hydrolyzable organosilicon compound such as alkoxysilane and the hydrolyzate thereof are formed from one or more compounds selected from the group consisting of the following (a) to (c), and in the molecule: — (O—Si) _m —O— (wherein _m represents a natural number) has a bond.
(A) Formula (1): A compound represented by SiX ₄ .
(B) At least one partial hydrolysis product of the compound represented by the formula (1).
(C) At least one complete hydrolysis product of the compound represented by the formula (1).

As the hollow fine particles, fine particles of an inorganic compound can be used without particular limitation, but inorganic hollow fine particles in which cavities are formed inside the outer shell are preferable, and silica-based hollow fine particles can be particularly preferably used. . The inorganic hollow fine particles include (A) a single layer of an inorganic oxide, (B) a single layer of a composite oxide composed of several kinds of inorganic oxides, and (C) a double layer of the above (A) and (B). Things can be used.
The outer shell may be porous with pores, or the pores may be closed and the pores sealed against the outside of the outer shell. The outer shell is preferably a plurality of inorganic oxide coating layers comprising an inner first inorganic oxide coating layer and an outer second inorganic oxide coating layer. By providing the second inorganic oxide coating layer on the outer side, the fine pores of the outer shell are closed to make the outer shell dense, and furthermore, the inorganic hollow fine particles in which the inner pores are sealed can be obtained. In particular, when a fluorine-containing organic silicon compound is used for forming the second inorganic oxide coating layer, the refractive index is lowered, dispersibility in an organic solvent is improved, and antifouling properties are further imparted. Examples of such fluorine-containing organic silicon compounds include 3,3,3-trifluoropropyltrimethoxysilane, methyl-3,3,3-trifluoropropyldimethoxysilane, heptadecafluorodecylmethyldimethoxysilane, and heptadecafluorodecyl. Examples include trichlorosilane, heptadecafluorodecyltrimethoxysilane, trifluoropropyltrimethoxysilane, and tridecafluorooctyltrimethoxysilane.

  Although there is no restriction | limiting in particular in the average particle diameter of inorganic hollow microparticles, it is preferable that it is 5-2,000 nm, and it is more preferable that it is 20-100 nm. If the average particle size is less than 5 nm, the effect of lowering the refractive index due to hollowness may be reduced. When the average particle diameter exceeds 2,000 nm, the transparency is extremely deteriorated and the contribution due to diffuse reflection may be increased. The average particle diameter can be determined as a number average particle diameter by observation with a transmission electron microscope.

  In the antireflection laminate used in the present invention, the maximum reflectance of light with an incident angle of 5 degrees and a wavelength of 430 nm to 700 nm from the viewing side is usually 1.4% or less, preferably 1.3%. It is as follows. The reflectance at a wavelength of 550 nm at an incident angle of 5 degrees is usually 0.7% or less, and preferably 0.6% or less. Further, the maximum reflectance at a wavelength of 430 nm to 700 nm at an incident angle of 20 degrees is usually 1.5% or less, preferably 1.4% or less. The reflectance at an incident angle of 20 degrees and a wavelength of 550 nm is usually 0.9% or less, preferably 0.8% or less. When each reflectance is in the above range, a liquid crystal display device having excellent visibility without reflection of external light and glare can be obtained. For the reflectance, a spectrophotometer (UV-visible near-infrared spectrophotometer V-550, manufactured by JASCO Corporation) is used.

Further, the antireflection laminate has a reflectance variation of 20% or less, preferably 10% or less, before and after the steel wool test. If the variation in reflectance exceeds 20%, the screen may be blurred or glaring. The steel wool test is a test in which the surface of the antireflection laminate is rubbed back and forth 10 times with a load of 0.025 MPa applied to steel wool # 0000. The reflectance is measured five times at five arbitrary locations in the plane, and is calculated from the arithmetic average value of these measured values. The change in reflectance before and after the steel wool test was determined by the following formula. Rb represents the reflectance before the steel wool test, and Ra represents the reflectance after the steel wool test.
ΔR = (Rb−Ra) / Rb × 100 (%) (i)

Similarly, the fluctuation of the total light transmittance before and after the steel wool test is usually within 10%, preferably within 8%, more preferably within 6%. The total light transmittance is measured five times at five locations in the plane, and is calculated from the arithmetic average value of these measured values. The fluctuation of the total light transmittance before and after the steel wool test was determined by the following formula. Rc represents the total light transmittance before the steel wool test, and Rd represents the total light transmittance after the steel wool test.
ΔR = (Rc−Rd) / Rc × 100 (%) (ii)

  In the liquid crystal display device of the present invention, in addition to the exit side polarizer, the entrance side polarizer, the optical anisotropic body, the liquid crystal cell, and the antireflection laminate, other films or layers may be provided. In addition, a prism array sheet, a lens array sheet, a light diffusion plate, a light guide plate, a diffusion sheet, a brightness enhancement film, and the like can be arranged in one or more layers at appropriate positions. In the liquid crystal display device of the present invention, a cold cathode tube, a mercury flat lamp, a light emitting diode, electroluminescence, or the like can be used as a backlight.

FIG. 1 is a schematic view showing a transflective liquid crystal display device that can be used in the present invention.
The transflective liquid crystal display device includes a backlight and a light guide plate (21) in order from the bottom, a polarizing plate (20) on the top, and a half-wave plate (19) and a quarter-wave plate on the top. An optical anisotropic body consisting of (18) is provided. The half-wave plate (19) and the quarter-wave plate (18) have their slow axes intersecting at an angle of about 60 °. Furthermore, a transflective liquid crystal cell comprising a transparent electrode (17) having a partially reflecting function, a liquid crystal layer (16) and a transparent electrode (15) is provided thereon, and a quarter-wave plate (14). And an optical anisotropic body made of a half-wave plate (13). The half-wave plate (13) and the quarter-wave plate (14) have their slow axes intersecting at an angle of about 60 °. A polarizing plate (12) and an antireflection laminate (10) are stacked thereon.

FIG. 2 is a schematic view showing a reflective liquid crystal display device that can be used in the present invention.
The reflective liquid crystal display device includes, in order from the bottom, a reflective liquid crystal cell comprising a reflective plate (37), a liquid crystal layer (36) and a transparent electrode (35), a quarter wavelength plate (34) and a half wavelength plate ( 33), an optical anisotropic body, a polarizing plate (32), and an antireflection laminate (31). The half-wave plate (33) and the quarter-wave plate (34) have their slow axes intersecting at an angle of about 60 °. In the case of color display, a color filter layer is further provided on the upper side of the liquid crystal cell.

The present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples. Parts and% are based on weight unless otherwise specified.
Measurements and evaluations performed in Examples and Comparative Examples are as follows.
(Main refractive index)
Using an automatic birefringence meter [Oji Scientific Instruments Co., Ltd., KOBRA-21], the direction of the in-plane slow axis of the optical anisotropic body is obtained at a wavelength of 550 nm, the refractive index nx in the in-plane slow axis direction, The refractive index ny in the direction perpendicular to the slow axis and the refractive index nz in the thickness direction are measured.
(Retardation)
Measurements were made using a high-speed spectroscopic ellipsometer [JA Woollam, M-2000U].

(Reflectance)
The reflectance was determined using a spectrophotometer [manufactured by JASCO Corporation: “UV-visible near-infrared spectrophotometer V-570”.
(Refractive index of low refractive index layer and hard coat layer)
High-speed spectroscopic ellipsometry [J. A. Using Woollam, M-2000U], it was calculated from the spectrum in the wavelength region of 400 to 1000 nm when the incident angles were measured at 55, 60, and 65 degrees, respectively.
(Scratch resistance)
The surface state after reciprocating the surface 10 times with a load of 0.025 MPa applied to steel wool # 0000 is visually observed.
○: Scratches are not observed ×: Scratches are observed

(Visibility)
The panel when black was displayed was visually observed and evaluated in two stages.
○: No glare or reflection is seen ×: Glare or reflection is seen (broadband)
The liquid crystal display panel was installed in an environment with an ambient brightness of 500 lux, and the reflected color was visually observed.
○: Reflection color is black ×: Reflection color is blue (contrast ratio)
A liquid crystal display panel is installed in an environment with an ambient brightness of 500 lux. Using a transmissive mode liquid crystal display, the luminance at a position of 5 degrees from the front during dark display and bright display is measured by a color luminance meter (Topcon Corporation). Manufactured by a color luminance meter BM-7). Then, the ratio between the brightness of bright display and the brightness of dark display (= brightness of bright display / brightness of dark display) is calculated, and this is used as contrast (CR). The greater the contrast (CR), the better the visibility.

(Production Example 1) Production of raw film 1 A pellet of a norbornene-based polymer (trade name: ZEONOR 1420R, manufactured by Nippon Zeon Co., Ltd., glass transition temperature: 136 ° C., saturated water absorption: less than 0.01% by weight) For 4 hours at 110 ° C. Then, a short disk extrusion having a coat hanger type T-die having a lip width of 650 mm with an average surface roughness Ra = 0.04 μm, in which a leaf disk-shaped polymer filter (filtration accuracy of 30 μm) is installed, and the tip of the die lip is chrome-plated The pellets were melt extruded at 260 ° C. using a machine to obtain a raw film 1 having a thickness of 100 μm and a width of 600 mm. The retardation value [Re (550)] was 3 nm.

(Production Example 2) Preparation of raw fabric film 2 Layer (II layer) made of norbornene polymer used in Production Example 1, styrene-maleic acid copolymer (manufactured by Nova Chemical Co., Ltd., trade name “Daylark D332”, A layer (I layer) composed of a glass transition temperature of 130 ° C. and an oligomer component content of 3% by weight, and a modified ethylene-vinyl acetate copolymer (manufactured by Mitsubishi Chemical Co., Ltd., trade name “Modic AP A543”, Vicat softening point 80 ° C) is an original film in which an adhesive layer (III layer) is laminated in the order of II layer (30 μm) -III layer (6 μm) -I layer (150 μm) -III layer (6 μm) -II layer (30 μm) 2 was obtained by coextrusion molding.

Production Example 3 Preparation of High Refractive Index Layer Composition H1 Hexafunctional urethane acrylate oligomer (trade name: NK Oligo U-6HA, Shin-Nakamura Chemical Co., Ltd.) 30 parts, butyl acrylate 40 parts, isoboronyl methacrylate ( Product name: 30 parts of NK Ester IB (manufactured by Shin-Nakamura Chemical Co., Ltd.) and 10 parts of 2,2-diphenylethane-1-one were mixed with a homogenizer, and a 40% by weight methyl isobutyl ketone dispersion of antimony pentoxide fine particles (average) Particle diameter 20 nm: hydroxyl groups are bonded to the antimony atoms appearing on the surface of the pyrochlore structure at a ratio of 1)), and the weight of the antimony pentoxide fine particles is 50 in the total solid content H1 of the high refractive index layer forming composition H1. By mixing at a ratio of weight%, a composition H1 for forming a high refractive index layer was prepared.

(Production Example 4) Preparation of composition L1 for forming a low refractive index layer 356 parts of methanol was added to 208 parts of tetraethoxysilane, 18 parts of water and 18 parts of 0.01N hydrochloric acid aqueous solution were further added, and mixed well using a disper. To obtain a mixed solution. The mixed solution was stirred for 2 hours in a constant temperature bath at 25 ° C. to obtain a silicone resin solution having a weight average molecular weight of 850. Next, as a hollow silica fine particle, a hollow silica isopropanol dispersion sol (solid content 20 wt%, average primary particle diameter of about 35 nm, outer shell thickness of about 8 nm, manufactured by Catalyst Kasei Kogyo Co., Ltd.) is added to the silicone resin solution. / Silicon resin (condensed compound equivalent) is added so that the weight ratio is 70/30 based on the solid content, and further diluted with methanol so that the total solid content is 1% by weight, for forming a low refractive index layer Composition L1 was prepared.

(Production Example 5) Preparation of coating solution L2 for forming a low refractive index layer Hollow silica particles / silicone resin (condensed compound equivalent) was made to have a weight ratio of 8: 2 on a solid basis, and composition L1 Similarly, a composition L2 for forming a low refractive index layer was obtained.

(Production Example 6) Preparation of composition L3 for forming a low refractive index layer 90 parts of methyl methacrylate, 40 parts of n-butyl acrylate, 20 parts of γ-metaloxypropyltrimethoxysilane, and 130 parts of xylene were mixed and stirred. Warming to 80 ° C. gave a mixture. Next, a solution of 4 parts of azobisisovaleronitrile in 10 parts of xylene was added dropwise to the 80 ° C. mixture over 30 minutes. After the addition, the mixture was maintained at 80 ° C. for 5 hours to obtain a silyl group having a solid content concentration of 50%. A vinyl resin solution containing was obtained.
The molecular weight of the silyl group-containing vinyl resin (molecular weight in terms of polystyrene as measured by gel permeation chromatography) was about 12,000, and it was estimated that the resin contains an average of 6 silyl groups per molecule. .
Next, 100 parts of methyltrimethoxysilane, 10 parts of dimethyldimethoxysilane, 50 parts of the silyl group-containing vinyl resin solution obtained above, 10 parts of aluminum tris (ethyl) acetoacetate, and 30 parts of isopropyl alcohol are mixed, and further ion exchange is performed. 30 parts of water was added and reacted at 60 ° C. for 4 hours. Next, the mixture was cooled to room temperature, and 7 parts of acetylacetone was added to obtain a composition L3 for forming a low refractive index layer.

(Production Example 7) Production of polarizer A polyvinyl alcohol film having an average polymerization degree of about 2,400 and a saponification degree of 99.9 mol% or more and a thickness of 75 μm was uniaxially stretched at a draw ratio of 5 times by a dry method, and further a tension state was obtained. While being kept, it was immersed in pure water at 60 ° C. for 1 minute. Next, it was immersed in an aqueous solution having a weight ratio of iodine / potassium iodide / water of 0.15 / 5/100 at 28 ° C. for 35 seconds and dyed. Thereafter, the mixture was immersed in an aqueous solution of potassium iodide / boric acid / water having a weight average molecular weight of 5,000 at a weight ratio of 26 / 9.5 / 100 at 76 ° C. for 300 seconds. After being washed with pure water at 15 ° C. for 2 seconds and then dried at 50 ° C., a polarizer having iodine adsorbed and oriented on polyvinyl alcohol was obtained.

(Production Example 8) Production of Polarizer P One side of a triacetyl cellulose film (KC8UX2M) manufactured by Konica Minolta Co., Ltd. was coated with 25 ml / ■ of 1.5N potassium hydroxide in isopropyl alcohol and dried at 25 ° C. for 5 seconds. did. The surface of the film was dried by washing with running water for 10 seconds and blowing air at 25 ° C. In this way, only one surface of the triacetylcellulose film was saponified.
The surface of the saponified film was laminated on one side of the polarizer obtained in Production Example 9 by using a roll-to-roll method using a polyvinyl alcohol-based adhesive, and triacetylcellulose was applied to the incident side of the polarizer. Films were laminated to obtain a polarizer P.

(Production Example 9) Production of optical anisotropic bodies C1, C2 and C3 The raw film 1 obtained in Production Example 1 was subjected to oven temperature (preheating temperature, stretching temperature, heat setting temperature) 140 using a stretching machine. Stretching was performed at 0 ° C., a stretching speed of 6 m / min, and a longitudinal stretching ratio of 1.5 times and 1.3 times to obtain optical anisotropic bodies C1 and C2, respectively.
The retardation values [Re (550)] at a wavelength of 550 nm of the obtained optical anisotropic bodies C1 and C2 were 265 nm and 132.5 nm, respectively.
On one side of the optical anisotropic body C1, the optical anisotropic body C2 is passed through an acrylic adhesive (Sumitomo 3M, DP-8005 clear) so that the crossing angle of each slow axis is 59 °. As a result, a bonded optically anisotropic body C3 was obtained. The ratio Re (450) / Re (550) between Re (550) of the optical anisotropic body C3 and the retardation value [Re (450)] at a wavelength of 450 nm was 1.005.

(Production Example 10) Production of optical anisotropic body C4 On one side of optical anisotropic body C1, a product name NH film manufactured by Nippon Oil Co., Ltd. was passed through an acrylic adhesive (Sumitomo 3M, DP-8005 clear), respectively. A bonded optically anisotropic body C4 was obtained so that the crossing angle of the slow axes of the film was 59 °. The ratio Re (450) / Re (550) of Re (550) of this optical anisotropic body C4 to the retardation value [Re (450)] at a wavelength of 450 nm was 0.86.

(Production Example 11) Production of optical anisotropic bodies C5 and C6 The original film 2 was stretched at a stretching temperature of 138 ° C, a stretching ratio of 1.5 times, and a stretching speed of 115% / min with respect to the width direction using a tenter stretching machine. Then, the film was obliquely tilted in the direction of -13 ° and wound up in a roll shape over 3000 m to obtain an optical anisotropic body C5.
The retardation Re (550) at a wavelength of 550 nm of the obtained optical anisotropic body C5 was measured and found to be 137.2 nm.
On one side of the optical anisotropic body C5, the optical anisotropic body C1 obtained in Production Example 9 crosses each slow axis through an acrylic adhesive (DP-8005 clear, manufactured by Sumitomo 3M Limited). Bonded optical anisotropic body C6 was obtained so that the angle was 59 °. Re (450) / Re (550) of the optical anisotropic body C6 was 0.81.

(Production Example 12) Production of optical anisotropic bodies C7, C8 and C9 The raw film 1 obtained in Production Example 1 was subjected to oven temperature (preheating temperature, stretching temperature, heat setting temperature) 170 using a stretching machine. Stretching was performed at 0 ° C., a film feed speed of 6 m / min, and a longitudinal stretching ratio of 1.75 times and 1.45 times to obtain optical anisotropic bodies C7 and C8, respectively.
The obtained optical anisotropic bodies C7 and C8 had retardation values Re (550) at a wavelength of 550 nm of 265 nm and 132.5 nm, respectively.
On one side of the optical anisotropic body C7, the optical anisotropic body C8 is passed through an acrylic adhesive (manufactured by Sumitomo 3M, DP-8005 clear) so that the crossing angle of each slow axis is 59 °. Thus, an optically anisotropic body C9 was obtained. Re (450) / Re (550) of this optical anisotropic body C9 was 1.010.

(Production Example 13) Preparation of Polarizing Plate 2A with Low Refractive Index Layer Corona discharge treatment on both surfaces of the raw film 1 obtained in Production Example 1 using a high frequency transmitter (high frequency power supply AGI-024 manufactured by Kasuga Denki Co.) Was performed at an output of 0.8 KW to obtain a base film having a surface tension of 0.072 N / m.
Next, the hard coat layer forming composition H1 obtained in Production Example 3 was applied to one side of the base film using a die coater, and dried for 5 minutes in a drying oven at 80 ° C. Got. Then, the laminated film 1A which irradiated with the ultraviolet-ray (integrated irradiation amount 300mJ / cm2) and laminated | stacked the hard-coat layer of thickness 5 micrometers was obtained. The hard coat layer had a refractive index of 1.62 and a pencil hardness of H.
On the hard coat layer side of the laminated film 1A, the low refractive index layer-forming composition L1 obtained in Production Example 4 was applied with a wire bar coater, left to stand for 1 hour and dried, and the resulting coating was applied. Heat treatment was performed in an oxygen atmosphere at 120 ° C. for 10 minutes to obtain a substrate with a low refractive index layer in which a low refractive index layer having a thickness of 100 nm was laminated. Roll-toe using an acrylic adhesive so that the surface of the obtained base material with a low refractive index layer on which the low refractive index layer is not laminated overlaps one side of the polarizer obtained in Production Example 7. By laminating by a roll method, a polarizing plate 2A with a low refractive index layer was obtained.

(Production Example 14) Manufacture of observer-side polarizing plate PO1 The optically anisotropic body C3 obtained in Production Example 9 and the polarizing plate 2A with a low refractive index layer obtained in Production Example 13 were combined with a polarizing plate with a low refractive index layer. The crossing angle between the transmission axis of the plate 2A and the slow axis of the optical anisotropic body C1 laminated on the optical anisotropic body C3 is 15 °, and the C1 side of the optical anisotropic body C3 and the polarized light with a low refractive index layer The observer side polarizing plate PO1 was prepared by stacking so that the polarizer side of the plate 2A was in contact therewith.

Production Example 15 Production of Backlight Side Polarizing Plate PB1 The optical anisotropic body C3 obtained in Production Example 9 and the polarizer P obtained in Production Example 8 were combined with the transmission axis of the polarizer P and the optical anisotropic body. The backlight is laminated so that the crossing angle of the slow axis of the optical anisotropic body C1 laminated on C3 is 15 ° and the C1 side of the optical anisotropic body C3 and the polarizer side of the polarizer P are in contact with each other. A side polarizing plate PB1 was produced.

(Example 1) Manufacture of liquid crystal display device 1 As a TN mode transflective liquid crystal cell, the pretilt angle of the two interfaces of the base is 2 degrees, the twist angle is 70 degrees to the left twist, Δnd is 230 nm in the reflective display section, and the transmissive display section And approximately 262 nm were used. The liquid crystal film thickness was 3.5 μm in the reflective electrode region (reflective display portion) and 4.0 μm in the transparent electrode region (transmissive display portion).
The observer-side polarizing plate PO1 obtained in Production Example 14, the liquid crystal cell, and the backlight-side polarizing plate PB1 obtained in Production Example 15 are laminated in this order, and then contacted with the backlight-side polarizing plate. Similarly, a diffusion sheet, a light guide plate, and a backlight were assembled in this order to produce the liquid crystal display device 1. The evaluation results of the manufactured liquid crystal display device 1 are shown in Table 1.

Example 2 Production of Liquid Crystal Display 2 Observation in the same manner as in Production Example 14 except that the optical anisotropic body C4 obtained in Production Example 10 was used instead of the optical anisotropic body C3 in Production Example 14. A person-side polarizing plate PO2 was obtained.
Next, in Production Example 15, a backlight-side polarizing plate PB2 was obtained in the same manner as in Production Example 15, except that the optical anisotropic body C4 obtained in Production Example 10 was used instead of the optical anisotropic body C3. .
Furthermore, in Example 1, the observer side polarizing plate PO2 is used instead of the observer side polarizing plate PO1, and the backlight side polarizing plate PB2 is used instead of the backlight side polarizing plate PB1. A liquid crystal display device 2 was produced by the same method. The evaluation results of the manufactured liquid crystal display device 2 are shown in Table 1.

Example 3 Production of Liquid Crystal Display 3 Polycarbonate film (trade name Pure Ace WR-W, manufactured by Teijin Ltd.) with Re (450) / Re (550) of 0.86 and the low value obtained in Production Example 13 In the polarizing plate 2A with a refractive index layer, the crossing angle between the transmission axis of the polarizing plate 2A with the low refractive index layer and the slow axis of the polycarbonate film is 45 °, and the polarization of the polarizing film 2A with the polycarbonate film and the low refractive index layer The observer side polarizing plate PO3 was produced by stacking so that the child side was in contact.
Next, the above-mentioned polycarbonate film and the polarizer P obtained in Production Example 8 were used, and the crossing angle between the transmission axis of the polarizer P and the slow axis of the polycarbonate film was 45 °, and the polarization of the polycarbonate film and the polarizer P was The backlight side polarizing plate PB3 was produced by stacking so that the child sides were in contact with each other.
Furthermore, in Example 1, the observer side polarizing plate PO3 is used instead of the observer side polarizing plate PO1, and the backlight side polarizing plate PB3 is used instead of the backlight side polarizing plate PB1. A liquid crystal display device 3 was produced by the same method.
The evaluation results of the manufactured liquid crystal display device 3 are shown in Table 1.

Example 4 Production of Liquid Crystal Display 4 Observation in the same manner as in Production Example 14 except that the optical anisotropic body C6 obtained in Production Example 11 was used instead of the optical anisotropic body C3 in Production Example 14. A person-side polarizing plate PO4 was obtained.
Next, in Production Example 15, a backlight-side polarizing plate PB4 was obtained in the same manner as in Production Example 15, except that the optical anisotropic body C6 obtained in Production Example 11 was used instead of the optical anisotropic body C3. .
Further, in Example 1, the observer side polarizing plate PO4 is used instead of the observer side polarizing plate PO1, and the backlight side polarizing plate PB4 is used instead of the backlight side polarizing plate PB1. The liquid crystal display device 4 was produced by the same method.
The evaluation results of the manufactured liquid crystal display device 4 are shown in Table 1.

(Example 5) Production of liquid crystal display device 5 In Production Example 13, the composition L2 for forming a low refractive index layer obtained in Production Example 5 was used in place of the composition L1 for forming a low refractive index layer. A polarizing plate 2B with a low refractive index layer was obtained in the same manner as in Production Example 13.
Subsequently, an observer-side polarizing plate PO5 was obtained in the same manner as in Manufacturing Example 14 except that the polarizing plate 2B with a low refractive index layer was used instead of the polarizing plate 2A with a low refractive index layer in Manufacturing Example 14.
Further, in Example 1, the liquid crystal display device 5 was produced in the same manner as in Example 1 except that the observer side polarizing plate PO5 was used instead of the observer side polarizing plate PO1.
The evaluation results of the manufactured liquid crystal display device 5 are shown in Table 1.

Comparative Example 1 Production of Liquid Crystal Display Device 6 The optical anisotropic body C9 obtained in Production Example 12 and the polarizing plate 2A with a low refractive index layer obtained in Production Example 13 are combined with the polarizing plate 2A with a low refractive index layer. The crossing angle of the slow axis of the optical anisotropic body C7 laminated on the optical anisotropic body C9 is 15 °, and the C7 side of the optical anisotropic body C9 and the polarizing plate 2A with a low refractive index layer Were laminated so that the polarizer side would be in contact with each other, to produce an observer side polarizing plate PO6.
Next, an optical anisotropic body C7 obtained by stacking the optical anisotropic body C9 obtained in Production Example 12 and the polarizer P obtained in Production Example 8 on the transmission axis of the polarizer P and the optical anisotropic body C9. The observer side polarizing plate PB5 was produced by stacking so that the crossing angle of the slow axis was 15 ° and the C7 side of the optical anisotropic body C9 was in contact with the polarizer side of the polarizer P.
Further, in Example 1, the observer side polarizing plate PO6 is used instead of the observer side polarizing plate PO1, and the backlight side polarizing plate PB5 is used instead of the backlight side polarizing plate PB1. A liquid crystal display device 6 was produced by the same method.
The evaluation results of the manufactured liquid crystal display device 6 are shown in Table 1.

(Comparative Example 2) Production of liquid crystal display device 7 In Production Example 13, the composition for forming low refractive index layer L3 obtained in Production Example 6 was used instead of the composition for forming low refractive index layer L1. A polarizing plate 2C with a low refractive index layer was obtained in the same manner as in Production Example 13.
Subsequently, an observer-side polarizing plate PO7 was obtained in the same manner as in Manufacturing Example 14 except that the polarizing plate 2C with a low refractive index layer was used instead of the polarizing plate 2A with a low refractive index layer in Manufacturing Example 14.
Further, in Example 1, the liquid crystal display device 7 was produced in the same manner as in Example 1 except that the observer side polarizing plate PO7 was used instead of the observer side polarizing plate PO1.
The evaluation results of the manufactured liquid crystal display device 7 are shown in Table 1.

(Comparative example 3) Production of liquid crystal display device 8 On the surface having the hard coat layer of the laminated film 1A obtained in Production Example 13, an MgF ₂ layer 89 nm, a TiO ₂ layer 112 nm, and an MgF ₂ layer 188 nm were arranged in this order. It was used and laminated at a substrate temperature of 80 ° C. to obtain a three-layer antireflection layer laminated film. The surface on the side where the antireflection layer of the obtained antireflection layer laminated film is not laminated is overlapped with one side of the polarizer obtained in Production Example 7, and bonded using an acrylic adhesive, A polarizing plate 2D with an antireflection layer was obtained.
Subsequently, an observer-side polarizing plate PO8 was obtained in the same manner as in Manufacturing Example 14 except that the polarizing plate 2D with an antireflection layer was used instead of the polarizing plate 2A with a low refractive index layer in Manufacturing Example 14.
Further, in Example 1, a liquid crystal display device 8 was produced in the same manner as in Example 1 except that the observer side polarizing plate PO8 was used instead of the observer side polarizing plate PO1.
The evaluation results of the manufactured liquid crystal display device 8 are shown in Table 1.

It is a figure which shows the one aspect | mode of the transflective liquid crystal display device of this invention. It is a figure which shows the one aspect | mode of the reflection type liquid crystal display device of this invention.

Explanation of symbols

10, 31, 32: Antireflection laminate; 12, 20, 32: Polarizing plate; 13, 19, 33: 1/2 wavelength plate; 15, 35: Transparent electrode; 16, 36: Liquid crystal layer; Transparent electrode having function; 37: reflector; 14, 18, 34 ... quarter-wave plate, 21 ... backlight and light guide plate

Claims (4)

A liquid crystal display device having an exit side polarizer, an optical anisotropic body, and a liquid crystal cell,
Ratio Re (450) / Re (550) of the in-plane retardation value [Re (550)] measured at a wavelength of 550 nm and the in-plane retardation value [Re (450)] measured at a wavelength of 450 nm. ) Is 1.007 or less,
A reflective or transflective liquid crystal comprising an antireflection laminate comprising a low refractive index layer composed of aerogel and having a refractive index of 1.37 or less on the side farther from the liquid crystal cell of the exit side polarizer Display device. The liquid crystal display device according to claim 1, wherein the optical anisotropic body has Re (550) of 125 to 150 nm. The liquid crystal display device according to claim 1, wherein the optical anisotropic body includes one obtained by stretching and aligning a transparent resin film or one obtained by aligning and fixing a liquid crystalline compound. The liquid crystal display device according to claim 1, wherein the optical anisotropic body includes one obtained by stretching and aligning a transparent resin film having negative intrinsic birefringence.

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