JP2005208607A - Manufacturing method for laminated polarizing plate, laminated polarizing plate obtained by the method, and image display apparatus using the laminated polarizing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated polarizing plate manufacturing method with which the occurrence of a projection and a swelled part on a cut surface can be prevented in manufacturing the laminated polarizing plate which is excellent in self-sustainability. <P>SOLUTION: The laminated polarizing plate is manufactured by laminating a polarizing plate and a resin film, and then, cutting the laminated body with dicing equipment. A film having a light transmissivity of ≥80%, and also, having a glass transfer temperature of ≥100°C is used as the resin film. It is preferable to use an epoxy-based resin film as the resin film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a laminated polarizing plate, a laminated polarizing plate obtained thereby, and an image display device using the same.

  In a liquid crystal display device, a polarizing plate is generally bonded to both surfaces of a liquid crystal cell. However, when the liquid crystal cell with the polarizing plate attached in this way is applied to a viewfinder such as a video camera or a digital camera, or a projector, the following problems occur.

  The viewfinder, projector, or the like takes a form in which a light source is irradiated from the back surface of the liquid crystal cell and an illuminated image is enlarged and projected by a magnifying lens system disposed in front of the liquid crystal cell. Therefore, the focal point of the magnifying lens is generally adjusted to the color filter disposed inside the liquid crystal cell. However, since the focal point of the magnifying lens system is close to the liquid crystal cell, as a result It often goes into depth. Then, if foreign matter such as dust adheres to the polarizing plate, even this foreign matter enters within the focal depth of the magnifying lens system, so the outline of this foreign matter is also projected, and the display quality is significantly reduced. It will become. In particular, since the polarizing plate is generally produced by bonding a polarizing film and a transparent protective layer, foreign matter is mixed in the polarizing plate during the production, or when adhering to the liquid crystal cell, There is a possibility that foreign matter may enter the interface between the liquid crystal cell and the polarizing plate.

In recent years, in order to solve such a problem, a method of disposing a polarizing plate with a sufficient distance outside the liquid crystal cell has been newly disclosed (for example, see Patent Document 1). Thus, if the polarizing plate is disposed at a position sufficiently away from the liquid crystal cell, the polarizing plate will not be focused even if the magnification lens system is focused on the liquid crystal cell. For this reason, even when a foreign substance is mixed inside the polarizing plate, the foreign substance does not enter the depth of focus, and it is possible to prevent the display quality from being affected.
JP-A-6-258637

  However, if it is set as the form of the said patent document 1, the following problems will arise. That is, the polarizing plate has poor rigidity and is not self-supporting, and it is difficult to arrange the polarizing plate at a sufficient distance from the liquid crystal cell. For this reason, it is essential to dispose a cover member on the outside of the liquid crystal cell substrate and attach a polarizing plate thereon. However, such a structure complicates the manufacturing process of the liquid crystal display device and causes problems such as an increase in size, cost, and a reduction in screen size. Such a problem occurs not only in the liquid crystal display device but also in other display devices.

  Accordingly, the present invention provides a production method capable of producing a laminated polarizing plate that can be arranged at a certain distance from a display device such as a liquid crystal cell, and a laminated plate polarization obtained thereby. It is an object of the present invention to provide a board and an image display device using the same.

  In order to achieve the above object, the manufacturing method of the present invention is a manufacturing method of a laminated polarizing plate, and has a polarizing film, a light transmittance of 80% or more, and a glass transition temperature of 100 ° C. or more. It is a manufacturing method including a laminating step of laminating a resin film to form a laminate film, and a dicer cutting step of dicing the laminate film to divide it into laminated polarizing plates.

  The laminated polarizing plate of the present invention is a laminated polarizing plate in which a polarizing plate and a resin film are laminated, and is a laminated polarizing plate obtained by the production method of the present invention.

  The image display device of the present invention is an image display device including an image display element and a polarizing plate, wherein the polarizing plate is the laminated polarizing plate of the present invention, and the laminated polarizing plate is The image display device is arranged at a certain distance from the image display element.

  In order to achieve the above object, the present inventors first made a series of studies on the self-supporting property of the polarizing plate. As a result, if a resin film having a light transmittance of 80% or more and a glass transition temperature of 100 ° C. or more is laminated on the polarizing film, the rigidity of the polarizing film can be improved while maintaining transparency. As a result, it was found that self-reliance can be imparted. Next, the laminate film needs to be cut into various shapes and sizes according to the use of the polarizing plate. However, when the conventional cutting method is applied to the cutting of the laminate film, Problems arise. In other words, conventional laser irradiation was used exclusively for cutting a polarizing plate, but when the polarizing plate was cut with a laser, the polarizing plate deteriorated due to the heat of the laser, and a protrusion such as a whisper on the cut surface. Or the cut surface is raised. The protrusions are difficult to remove even after washing. In addition, when the polarizing plate on which such protrusions or protrusions are generated is attached to the housing of the product, the protrusions are mixed into the housing, or attachment failure occurs due to the protrusions. This problem also occurs in the laminate film of the present invention. In order to solve this problem, the present inventors have conducted further research focusing on the cutting method. When the laminate film is cut by a dicer, the above-described protrusions and bumps are formed. It was found that the occurrence can be prevented. In addition, when the conventional polarizing plate is cut by the dicer method, protrusions and protrusions still occur on the cut surface. However, when Dicer cutting is applied to the laminate film, no protrusions and bumps are generated. However, the reason for this is unknown. As described above, according to the manufacturing method of the present invention, it is possible to prevent the occurrence of protrusions and bulges on the cut surface. Therefore, the laminated polarizing plate of the present invention obtained by the manufacturing method is applied to a product casing. At the time of attachment, problems such as mixing of projections and poor attachment can be prevented. Moreover, since the laminated polarizing plate obtained by the production method of the present invention is excellent in self-supporting property, for example, in a liquid crystal display device used in a viewfinder and a projector such as a digital camera, it is independent from the liquid crystal cell. Can be arranged with a distance of. In addition, in the present invention, the effect of employing dicer cutting is that gas is generated by laser irradiation, whereas gas generation is prevented by dicer cutting, and the degree of cleaning processing in the subsequent process can be reduced. In addition, cutting by the dicer method is a method of cutting a blade containing abrasive grains such as diamond in a metal or resin surface while rotating at high speed, and there are a wet method using water and a dry method not using water. is there.

  Hereinafter, the production method of the present invention will be described with examples. As described above, the production method of the present invention is a laminate in which a polarizing plate film and a resin film having a light transmittance of 80% or more and a glass transition temperature of 100 ° C. or more are laminated to form a laminate film. It is a manufacturing method including the process and the dicer cutting process of dicing the said laminated body film and dividing | segmenting into a lamination type polarizing plate. The said resin film WHEREIN: The preferable range of the said light transmittance is 80 to 100%, More preferably, it is 85 to 100%, The said glass transition temperature has the preferable range of 100 to 400 degreeC, More preferably, it is 150. It is the range of -400 degreeC.

  It does not restrict | limit especially as said polarizing plate film, A conventionally well-known polarizing plate as mentioned later can be used. On the other hand, the resin film is not particularly limited as long as it has a transmittance of 80% or more and a glass transition temperature of 100 ° C. or higher, but a resin film having excellent transparency, impact resistance, and heat resistance is preferable. A specific example will be described later. The glass transition temperature can be determined from the peak value of tan δ from the result of viscoelasticity measurement from −30 ° C. to 200 ° C., for example, using a viscoelasticity measuring apparatus ARES manufactured by TA Instruments Japan. .

  The thickness of the resin film is not particularly limited, but is preferably 0.05 mm to 1.5 mm, for example.

  The lamination method of the polarizing plate film and the resin film is not particularly limited, and can be performed by a conventionally known method. Moreover, when laminating | stacking with an adhesive agent or an adhesive, the kind in particular is not restrict | limited, The below-mentioned thing can be used.

  Next, cutting (dicing) by the dicer method will be described. The dicing apparatus used for the dicing is not particularly limited, and for example, a cutting dicing apparatus (dicer) for cutting a semiconductor wafer, various glasses, plastics, a semiconductor package, a substrate material, or the like can be used. As described above, the dicing apparatus includes a wet type using water and a dry type not using water, both of which can be used. There are a single dicer and a dicer to which a plurality of blades such as a dual dicer can be mounted, both of which can be used. The method for fixing the laminate to the dicing apparatus is not particularly limited. For example, there are a method of fixing with both an adhesive tape and a dicing ring, and a method of fixing to a dedicated fixing jig by suction. As the adhesive tape, for example, a normal pressure sensitive type or a radiation curable type can be used. In particular, it is preferable that the adhesive strength is strong before dicing and that the adhesive strength can be significantly reduced by irradiation after dicing. The thickness of the pressure-sensitive adhesive tape is not particularly limited, but is, for example, in the range of 30 to 1000 μm, and preferably in the range of 100 to 300 μm from the viewpoint of securing a depth for cutting a tape described later.

  The dicing blade mounted on the dicing apparatus is not particularly limited, and for example, a semiconductor wafer, various types of glass, plastic, a semiconductor package, and a substrate for cutting a substrate can be used. The thickness of the dicing blade is not particularly limited, but is, for example, in the range of 30 to 1000 μm, preferably in the range of 30 to 500 μm, more preferably in the range of 30 to 500 μm from the viewpoint of cutting stability and cutting efficiency. It is in the range of ˜300 μm. The roughness of the dicing blade is not particularly limited, but is, for example, in the range of # 200 to # 1000 from the viewpoints of life, smoothness of the cut surface, clogging, and the like. The number of rotations of the dicing blade at the time of dicing is, for example, in the range of 10,000 to 60000 rpm, and preferably in the range of 30000 to 60000 rpm from the viewpoint of unevenness of the cut surface, cutting speed, and the like. The direction of rotation is not particularly limited, and there is no problem even in a so-called up mode, down mode, or a combination thereof.

  The dicing speed is, for example, in the range of 10 to 300 mm / second, and preferably in the range of 50 to 200 mm / second from the viewpoints of cutting efficiency and stability of the cut surface.

  When the above-described wet dicer is used, during dicing, cutting is performed while water is applied for the purpose of cooling and cleaning, and the amount of water at that time is optimally adjusted depending on the apparatus and conditions.

  When using the adhesive tape, it is preferable to cut into the tape. The depth of cutting the tape is, for example, in the range of more than 0 μm and not more than 200 μm, and preferably in the range of 30 to 120 μm from the viewpoint of the stability of the cutting quality.

  Normally, in dicing, one line is cut once, but one line can be cut a plurality of times. In this case, there is an advantage that the cut surface becomes smoother and dust on the cut line can be removed. In this case, if a dual dicer is used, cutting can be performed more efficiently. The first cutting depth and the second cutting depth can be arbitrarily set. It is possible to cut all of the laminate in the first cut, and in the second cut, the same line can be cut and cleaned, and the depth is changed between the first cut and the second cut. It is also possible to reduce the load. Moreover, the order of cutting can also be set arbitrarily. The cutting direction and cutting speed on the same line can be changed.

  The shape and size of the laminated polarizing plate cut out from the laminate are not particularly limited, and may be determined according to, for example, the shape and size of the image display device in which it is used. As the cut shape, for example, there is a quadrangle, and the cut may be performed in the absorption axis direction and the vertical axis direction (or the direction perpendicular to the polarization axis) of the polarizing plate in the laminate film. For example, in the case of a laminated polarizing plate applied to a liquid crystal display device used in a viewfinder of a video camera or a digital camera, for example, a laminated polarizing plate having a product size of 10 mm × 11 mm is obtained from a 200 mm × 200 mm square laminated film. At least 200 can be obtained.

  After cutting the laminated polarizing plate, it is preferable to perform a cleaning treatment as necessary. The type of cleaning is not particularly limited. For example, in the case of a wet process, liquid cleaning such as water, air cleaning that blows air (air blow), and the like may be used, and these may be combined. In order to remove excess water, air blow may be performed again.

  As described above, when dicing is performed on a dicing substrate such as a single adhesive tape to form a plurality of laminated polarizing plates, the other surface of these laminated polarizing plates (the dicing substrate) A surface protective sheet may be attached to the opposite surface) via an adhesive. In addition, after pasting a single surface protective sheet in this way, the dicing substrate on the surface opposite to the laminated polarizing plate is peeled off, and a single surface protective sheet is pasted on this surface instead. May be.

  The top view of FIG. 1 shows an example in which a plurality of laminated polarizing plates of the present invention cut into a square are arranged on a single surface protective sheet. In the figure, arrows A and B indicate the polarization axis of the polarizing plate or an absorption axis perpendicular thereto, and a and b indicate the cut surfaces of the laminated polarizing plate 21. As illustrated, a plurality of laminated polarizing plates 21 cut out in the polarization axis direction and the absorption axis direction are arranged on the surface protection sheet 22 at equal intervals. In the present invention, the arrangement distance (pitch) between the laminated polarizing plates is not particularly limited.

  Next, in the production method of the present invention, a conventionally known polarizing plate film can be used, and in general, a polarizing plate (polarizing film) having a transparent protective layer disposed on one side or both sides thereof can be used. The polarizer is not particularly limited, and a conventionally known polarizing film can be used. Specifically, for example, a film prepared by adsorbing a dichroic substance such as iodine or a dichroic dye to various films by using a conventionally known method, crosslinking, stretching, and drying are used. it can. Among these, a film that transmits linearly polarized light when natural light is incident is preferable, and a film that is excellent in light transmittance and degree of polarization is preferable. Examples of the various films for adsorbing the dichroic substance include hydrophilic polymer films such as PVA films, partially formalized PVA films, ethylene / vinyl acetate copolymer partially saponified films, and cellulose films. In addition to these, polyene oriented films such as PVA dehydrated products and polyvinyl chloride dehydrochlorinated products can also be used. Among these, PVA film is preferable. Moreover, although the thickness of the said polarizing film is the range of 5-80 micrometers, for example, it is not limited to this.

  The transparent protective layer is not particularly limited, and a conventionally known transparent film can be used. For example, a transparent protective layer having excellent transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, and the like is preferable. Specific examples of the material for such a transparent protective layer include, for example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as diacetyl cellulose and triacetyl cellulose, and acrylic polymers such as polymethyl acrylate and polymethyl methacrylate. Examples thereof include polymers, styrene polymers such as polystyrene and acrylonitrile / styrene copolymer (AS resin), and polycarbonate polymers. In addition, polyethylene, polypropylene, polyolefin having a cyclo or norbornene structure, polyolefin polymer such as ethylene / propylene copolymer, vinyl chloride polymer, nylon or aromatic polyamide polymer, imide polymer, sulfone polymer, polyether sulfone Polymers, polyether ether ketone polymers, vinylidene chloride polymers, vinyl alcohol polymers, vinyl butyral polymers, arylate polymers, polyoxymethylene polymers, epoxy polymers, blends of the above-mentioned various polymers, and the like. Among these, cellulose polymers such as triacetylcellulose are preferable. Although the thickness of a transparent protective film does not have limitation in particular, Generally it is 500 micrometers or less, 1-300 micrometers is preferable, More preferably, it is 5-200 micrometers.

  The polarizer and the transparent protective layer are laminated and integrated with, for example, an adhesive. Examples of the adhesive include isocyanate adhesives, polyvinyl alcohol adhesives, gelatin adhesives, vinyl latex adhesives, and water-based polyester adhesives.

  For the purpose of various treatments such as hard coat treatment, antireflection treatment, anti-sticking treatment, diffusion treatment, antiglare treatment, antiglare treatment with antireflection, antistatic treatment, and antifouling treatment on the surface of the polarizing film. It may be given accordingly.

  The hard coat treatment is intended to prevent scratches on the surface of the polarizing film, for example, by a method of forming a cured film having excellent hardness and slip properties on the surface of the film with an ultraviolet curable resin such as acrylic or silicone. It can be carried out. The antireflection treatment is performed for the purpose of preventing reflection of external light on the surface of the optical film, and can be performed by forming a conventionally known antireflection film (physical optical thin film, coating thin film) or the like.

  The anti-glare treatment is intended to prevent the external light from being reflected on the surface of the optical film and preventing the visibility of the light transmitted through the polarizing plate from being impaired. For example, a fine concavo-convex structure may be imparted to the film surface by thinning the film by a sandblasting method, an embossing method, or the like, or by a film forming method in which transparent fine particles are blended in a film forming material. The fine particles used for forming the fine surface irregularities have an average particle size of, for example, 0.5 to 50 μm, and are inorganic such as silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Transparent fine particles composed of a system material can be used. When forming a fine surface relief structure, the amount of fine particles used is generally about 2 to 50 parts by weight, preferably 5 to 25 parts by weight, per 100 parts by weight of the resin. The antiglare layer may also serve as a diffusion layer (viewing angle expanding function or the like) for diffusing the light transmitted through the polarizing plate to expand the viewing angle.

  Next, as the resin film that can be used in the production method of the present invention, those having excellent transparency, impact resistance, and heat resistance as described above are preferable. For example, epoxy resin, polyester resin, acrylic resin, methacrylic resin, Resin, polycarbonate (PC) resin, polyethylene naphthalate (PEN) resin, polyethylene terephthalate (PET) resin, triacetyl cellulose (TAC) resin, polynorbornene resin (for example, trade name ARTON resin) Manufactured by JSR), polyimide resins, polyetherimide resins, polyamide resins, polysulfone resins, polyphenylene sulfide resins, polyethersulfone resins, and the like. These resins may be used alone to produce the resin film, or two or more of them may be used in combination to produce the resin film. Among these, acrylic resins or epoxy resins are preferable.

  The epoxy resin preferably has an epoxy equivalent of 100 to 1000 and a softening point of 120 ° C. or less from the viewpoint of physical properties such as flexibility and strength of the obtained resin film. Furthermore, from the viewpoint of obtaining an epoxy-based resin-containing liquid that is excellent in coating property and developability to a film, for example, a two-component mixed type that exhibits a liquid state at a coating temperature, particularly at room temperature. It is preferable to use it.

  Examples of the epoxy resin include bisphenol A type, bisphenol F type, bisphenol S type, bisphenol type obtained by adding water thereto; novolak type such as phenol novolak type and cresol novolak type; triglycidyl isocyanurate type and hydantoin type Such as nitrogen-containing ring type; alicyclic type; aliphatic type; aromatic type such as naphthalene type; low water absorption type such as glycidyl ether type and biphenyl type; dicyclo type, ester type, ether ester type, etc. Examples include modified types. These resins may be used alone or in combination of two or more. Among these, bisphenol A type epoxy resins, alicyclic epoxy resins, and triglycidyl isocyanurate type epoxy resins are preferable, and alicyclic epoxy resins are particularly preferable from the viewpoint of discoloration prevention.

  Moreover, since the said epoxy resin is excellent in optical isotropy, it is preferable that a phase difference is 5 nm or less, Most preferably, it is 1 nm. Similarly, resins other than epoxy resins are preferably excellent in optical isotropy. Specifically, the phase difference is preferably 5 nm or less, and particularly preferably 1 nm or less.

  Epoxy resins include, for example, curing agents, curing accelerators, and anti-aging agents, modifiers, surfactants, dyes, pigments, anti-discoloring agents and ultraviolet absorbers that have been conventionally used as necessary. Various conventionally known additives such as these may be appropriately blended. For example, when an acid anhydride curing agent and a phosphorus curing catalyst are blended with an epoxy resin such as a bisphenol A type epoxy resin, an alicyclic epoxy resin, or a triglycidyl isocyanurate type, it can be cured.

  The said hardening | curing agent is not restrict | limited in particular, According to the kind of epoxy resin to be used, it determines suitably. For example, organic acid compounds such as tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid and methylhexahydrophthalic acid; ethylenediamine, propylenediamine, diethylenetriamine, triethylenetetramine and their amine adducts, metaphenylenediamine, diamino Amine compounds such as diphenylmethane and diaminodiphenyl sulfone; amide compounds such as dicyandiamide and polyamide; hydrazide compounds such as dihydragit; methylimidazole, 2-ethyl-4-methylimidazole, ethylimidazole, isopropylimidazole, 2, 4-dimethylimidazole, phenylimidazole, undecylimidazole, heptadecylimidazole, 2-phenyl-4-methylimidazole, etc. Imidazole compounds: methyl imidazoline, 2-ethyl-4-methyl imidazoline, ethyl imidazoline, isopropyl imidazoline, 2,4-dimethyl imidazoline, phenyl imidazoline, undecyl imidazoline, heptadecyl imidazoline, 2-phenyl-4-methyl imidazoline, etc. Imidazoline compounds; phenol compounds; urea compounds; polysulfide compounds; acid anhydride compounds and the like. These may be used alone or in combination of two or more. Among them, it is preferable to use acid anhydride compounds because they are excellent in preventing discoloration.

  Examples of the acid anhydride compounds include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, nadic anhydride, glutaric anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride. , Hexahydrophthalic acid anhydride, methyl hexahydrophthalic acid anhydride, methyl nadic acid anhydride, dodecenyl succinic acid anhydride, dichlorosuccinic acid anhydride, benzophenone tetracarboxylic acid anhydride, chlorendic acid anhydride, trihydroxyethyl And isocyanurate anhydride. Among these, colorless to light yellow and those having a molecular weight of about 140 to about 200 are preferable. Specific examples include trihydroxyethyl isocyanurate-modified phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride. And methylhexahydrophthalic anhydride.

  The blending ratio of the epoxy resin and the curing agent is, for example, when an acid anhydride curing agent is used as the curing agent, the acid anhydride equivalent is 0.5 to 1 with respect to 1 equivalent of the epoxy group of the epoxy resin. It is preferable to mix | blend so that it may become 5 equivalent, More preferably, it is 0.7-1.2 equivalent. If it is such a range, the more excellent hue and moisture resistance will be shown after hardening. In addition, also when using another hardening | curing agent individually or in combination of 2 or more types, the compounding ratio is based on the said equivalent ratio.

  Examples of the curing accelerator include tertiary amines, imidazoles, quaternary ammonium salts, organometallic salts, phosphorus compounds, urea compounds, and the like. Two or more types may be used in combination. Among these, tertiary amines, imidazoles and phosphorus compounds are particularly preferable.

  It is preferable that the compounding quantity of the said hardening accelerator is 0.05-7.0 weight part with respect to 100 weight part of epoxy resins, More preferably, it is 0.2-4.0 weight part. If it is such a range, sufficient hardening promotion effect can be acquired and discoloration can fully be prevented.

  The anti-aging agent is not particularly limited, and conventionally known materials can be used, and examples thereof include phenol compounds, amine compounds, organic sulfur compounds, phosphine compounds, and the like.

  The modifying agent is not particularly limited, and conventionally known ones can be used, and examples thereof include glycols, silicones and alcohols.

  A surfactant may be further added to the epoxy resin. By adding the surfactant, the surface of the film can be smoothed when the epoxy resin film is formed while being in contact with air by the casting method. Examples of the surfactant include silicones, acrylics, and fluorines, and silicones are particularly preferable.

  The method for producing the resin film is not particularly limited, and can be produced by a conventionally known method. Examples thereof include a casting method, a casting method, an injection method, an extrusion molding method, and a roll coating method.

  For example, a gas barrier layer, a hard coat layer, or the like may be formed on the resin film. The material for forming these layers, the forming method and the thickness thereof are not particularly limited. As an example of the forming material, polyvinyl alcohol or a partially saponified product thereof is preferable as the gas barrier layer, and a thermosetting or radiation curable (for example, UV, EB, etc.) three-dimensional cross-linked acrylic resin is used as the hard coat layer. Is preferred.

  In this invention, it is preferable to laminate | stack the said polarizing plate film and the said resin film, and to integrate with an adhesive agent or an adhesive. In this case, the adhesive or pressure-sensitive adhesive that can be used is not particularly limited, but for example, an acrylic or vinyl alcohol-based, silicone-based, polyester-based, polyurethane-based, polyether-based polymer adhesive or pressure-sensitive adhesive, Examples thereof include rubber adhesives and pressure-sensitive adhesives. In addition, an adhesive or pressure-sensitive adhesive composed of a water-soluble crosslinking agent of vinyl alcohol polymer such as glutaraldehyde, melamine, or oxalic acid can be used. For example, the adhesive or pressure-sensitive adhesive is hardly peeled off due to the influence of humidity or heat, and is excellent in light transmittance and polarization degree. Among these, acrylic adhesives or pressure-sensitive adhesives are most preferably used from the viewpoint of transparency and durability. The adhesive or the pressure-sensitive adhesive is not limited to the type such as a thermal crosslinking type, a light (ultraviolet ray, electron beam) crosslinking type, or the like. These adhesives and pressure-sensitive adhesives can be used for other purposes, for example, when the laminated polarizing plate of the present invention and a surface protective sheet are laminated.

  The acrylic adhesive or pressure-sensitive adhesive may have a transparent acrylic polymer as a main ingredient, and may be appropriately added with additives as necessary, or may be combined with an inorganic filler or the like. The acrylic polymer is mainly composed of at least one of acrylic acid alkyl ester and methacrylic acid alkyl ester, and has a hydroxyl group, a carboxyl group, an amino group, an amide group, a sulfone group in order to improve adhesion to the protective film of the polarizing plate. It is obtained by adding a modifying monomer that can be copolymerized with the main component having a polar group such as an acid group and a phosphoric acid group, and polymerizing them by a conventional method, and adjusting the heat resistance. For the purpose, a crosslinking treatment is appropriately performed as necessary.

  The acrylic acid alkyl ester or methacrylic acid alkyl ester is, for example, a linear or branched acrylic acid alkyl ester or methacrylic acid alkyl ester whose alkyl group has 1 to 18 carbon atoms, preferably 4 to 12 carbon atoms. can give. For example, butyl acrylate, isobutyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, isononyl acrylate, allyl acrylate, lauryl acrylate, stearyl acrylate, butyl methacrylate, isobutyl methacrylate, methacrylic acid Examples include hexyl, 2-ethylhexyl methacrylate, isooctyl methacrylate, isononyl methacrylate, allyl methacrylate, lauryl methacrylate, stearyl methacrylate, and the like. These may be used alone or in combination of two or more. . Monoethylenically unsaturated monomers copolymerizable with these acrylic acid alkyl esters or methacrylic acid alkyl esters may be used in combination with monomers having the following polar groups in order to increase adhesion to the polarizing plate. .

  Examples of the monomer having a polar group include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride, anhydrous Acid anhydride monomers such as itaconic acid; styrenesulfonic acid, allylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamide-2-methylpropanesulfonic acid, acrylamidepropanesulfonic acid, methacrylamidepropanesulfonic acid Sulfonic acid group-containing monomers such as sulfopropyl acrylate, sulfopropyl methacrylate, acryloyloxynaphthalenesulfonic acid, methacryloyloxynaphthalenesulfonic acid; 2-hydroxyethylacrylo Phosphoric acid group-containing monomers such as ruphosphate; acrylamide, N, N-dimethylacrylamide, N-butylacrylamide, N-methylolacrylamide, N-methylolpropaneacrylamide, methacrylamide, N, N-dimethylmethacrylamide, N-butylmethacrylamide N-substituted amide monomers such as N-methylol methacrylamide, N-methylol propane methacrylamide; aminoethyl acrylate, N, N-dimethylaminoethyl acrylate, t-butylaminoethyl acrylate, amino methacrylate Alkylaminoalkyl monomers such as ethyl, N, N-dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate; methoxyethyl acrylate, ethoxyethyl acrylate, methacryl Alkoxyalkyl monomers such as methoxyethyl and ethoxyethyl methacrylate; N-acryloyloxymethylenesuccinimide, N-acryloyl-6-oxyhexamethylenesuccinimide, N-acryloyl-8-oxyoctamethylenesuccinimide, N-methacryloyloxymethylenesuccinimide Succinimide monomers such as N-methacryloyl-6-oxyhexamethylenesuccinimide and N-methacryloyl-8-oxyoctamethylenesuccinimide; vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinyl Pyrimidine, vinyl piperazine, vinyl pyrazine, vinyl pyrrole, vinyl imidazole, vinyl oxazole, vinyl mole Vinyl monomers such as holine, N-vinylcarboxylic acid amides, styrene, α-methylstyrene, N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy groups such as glycidyl acrylate and glycidyl methacrylate Containing acrylic monomer: polyethylene glycol acrylate, polypropylene glycol acrylate, methoxyethylene glycol acrylate, methoxypolypropylene glycol acrylate, polyethylene glycol methacrylate, polypropylene glycol methacrylate, methoxyethylene glycol methacrylate, methoxypolypropylene glycol methacrylate, etc. Glycol-based acrylic ester monomer; tetrahydrofurfuryl acrylate, fluorine acrylate DOO, silicone acrylate, tetrahydrofurfuryl methacrylate, fluorine methacrylate, silicone methacrylate, acrylic ester monomers such as 2-methoxyethyl acrylate.

  When the acrylic acid alkyl ester or methacrylic acid alkyl ester is copolymerized with a monoethylenically unsaturated monomer, the blending ratio of the acrylic acid alkyl ester or methacrylic acid alkyl ester as the main component is, for example, 60 to 95. % By weight, preferably 80 to 95% by weight, and the blending ratio of the monoethylenically unsaturated monomer may be appropriately set so as to be 100% by weight together with the alkyl acrylate ester or the alkyl methacrylate ester. For example, it is 40 to 5% by weight, preferably 20 to 5% by weight. By using it in such a range, it is possible to obtain an anti-cracking adhesive having excellent adhesion to the polarizing plate and good impact force relaxation characteristics.

  The acrylic polymer can be prepared using a conventionally known method. For example, a mixture of the main component and two or more monomers of the polar group-containing monomer component can be prepared by a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, a suspension polymerization method, or the like. In this case, a polymerization initiator may be used as necessary, and examples thereof include a thermal polymerization initiator and a photopolymerization initiator.

  Examples of the thermal polymerization initiator include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, and di (2-ethoxyethyl) peroxide. Organic peroxides such as oxydicarbonate, t-butylperoxyneodecanoate, t-butylperoxybivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, diacetyl peroxide; 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane 1-carbonitrile), 2,2′-azobis (2, 4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethyl-4-methyl) Xylvaleronitrile), dimethyl 2,2′-azobis (2-methylpropionate), 4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2-hydroxymethylpropionitrile) ), 2,2′-azobis [2- (2-imidazolin-2-yl) propane] and the like.

  Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, methoxyacetophenone, and 2,2-dimethoxy. Acetophenone compounds such as 2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) -phenyl] -2-morpholinopropane-1; benzoin Benzoin ether compounds such as ethyl ether, benzoin isopropyl ether and anisoin methyl ether; α-ketol compounds such as 2-methyl-2-hydroxypropiophenone; ketal compounds such as benzyldimethyl ketal; 2-naphthalenesulfonyl Aromatic sulfonyl chloride compounds such as loride; Photoactive oxime compounds such as 1-phenone-1,1-propanedione-2- (ο-ethoxycarbonyl) oxime; benzophenone, benzoylbenzoic acid, 3,3′-dimethyl And benzophenone compounds such as -4-methoxybenzophenone.

  The usage-amount of these polymerization initiators can be suitably determined according to the kind within the range of 0.005-5 weight part per 100 weight part of monomers, for example. When using the said photoinitiator, it is preferable that it is 0.005-1 weight part, for example, 0.05-0.5 weight part especially. In such a range, the reactivity between the monomer and the photopolymerization initiator is further improved, so that the adhesiveness between the adhesive layer and the polarizing plate film or the resin film is further improved, and the hue is extremely excellent. An adhesive or pressure-sensitive adhesive is obtained. When using a thermal polymerization initiator, for the same reason as described above, for example, 0.01 to 5 parts by weight, particularly 0.05 to 3 parts by weight is preferable.

  In performing the polymerization reaction, a polyfunctional acrylate or methacrylate having two or more acryloyl groups or methacryloyl groups in the molecule as a cross-linking agent (internal cross-linking agent) is added together with the polymerization initiator as necessary. The shear strength may be increased by increasing the cohesive force of the impact force relaxation member. Such polyfunctional acrylates or methacrylates are, for example, hexanediol diacrylate, ethylene glycol diacrylate, (poly) propylene glycol diacrylate, neopentyl glycol diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, pentaerythritol. Triacrylate, dipentaerythritol hexaacrylate, epoxy acrylate, polyester acrylate, urethane acrylate, hexanediol dimethacrylate, (poly) ethylene glycol dimethacrylate, (poly) propylene glycol dimethacrylate, neopentyl glycol dimethacrylate, pentaerythritol dimethacrylate, Trimethylolpropane tri Methacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexa methacrylate.

  The polyfunctional acrylate or methacrylate is used in an amount of, for example, 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight per 100 parts by weight of the monomer. In addition, in the case of trifunctional or higher polyfunctionality, it is preferable to reduce the number. By setting it as such a range, the outstanding crosslinking degree is shown after photopolymerization, and it is excellent in the adhesiveness of an adhesive bond layer, a polarizing plate film, or a resin film.

  The polymerization reaction can be performed by, for example, a photopolymerization method such as ultraviolet rays or a thermal polymerization method, depending on the type of the polymerization initiator. From the viewpoint of processability to the pressure-sensitive adhesive sheet and physical properties of the adhesive, the photopolymerization method is particularly preferable. The photopolymerization method is preferably performed, for example, in an oxygen-free atmosphere substituted with an inert gas such as nitrogen gas, or in a state where it is shielded from air by coating with an ultraviolet transmissive film.

In the photopolymerization method, ultraviolet rays are electromagnetic radiation having a wavelength range of about 180 to 460 nm, but electromagnetic radiation having longer or shorter wavelengths may be used. As the ultraviolet ray source, for example, an irradiation device such as a mercury arc, a carbon arc, a low pressure mercury lamp, a medium / high pressure mercury lamp, a metal halide lamp, a chemical lamp, or a black light lamp can be used. The intensity of the ultraviolet light can be appropriately set by adjusting the distance to the irradiated object or the voltage. In consideration of irradiation time (productivity), it is usually desirable to use an integrated light amount of 0.5 to ¹⁰ J / cm ² . Furthermore, when the coating thickness of the adhesive is 0.2 mm or more, the adhesive swells due to the heat of polymerization, and the smoothness may be impaired. By cooling during photopolymerization, Swelling can be suppressed.

  If necessary, the adhesive or pressure-sensitive adhesive may further contain one or more plasticizers having good transparency. The blending amount is, for example, 5 to 300 parts by weight, preferably 10 to 200 parts by weight, per 100 parts by weight of the monomer (or polymer thereof).

  Examples of such plasticizers include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, di-2-ethylhexyl phthalate, diisononyl phthalate, diisodecyl phthalate, dibutylbenzyl phthalate, and dioctyl phthalate. Phthalic acid compounds such as butylphthalylbutyl glycolate, diisobutyl adipate, diisononyl adipate, diisodecyl adipate, dibutoxyethyl adipate, dibutyl sebacate, di-2-ethylhexyl sebacate, etc. Sebacic acid compounds such as triethylene phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresylphenyl phosphate, and other fatty acid compounds such as dioctyl sebacate and methylacetylricinolate , Epoxy compounds such as diisodecyl-4,5-epoxytetrahydrophthalate, trimellitic compounds such as tributyl trimellitic acid, tri-2-ethylhexyl trimellitic acid, tri-n-octyl trimellitic acid, triisodecyl trimellitic acid Other examples include butyl oleate, chlorinated paraffin, polypropylene glycol, polytetramethylene glycol, or polyoxyalkylene glycols such as polybutene and polyisobutylene.

  Furthermore, the adhesive or the pressure-sensitive adhesive may be, for example, a pigment having a near-infrared (800-1100 nm) or neon light (570-590 nm) absorption property or a pigment such as a dye, as long as the transparency is not impaired. Various additives such as tackifiers, antioxidants, anti-aging agents, UV absorbers, silane coupling agents, natural products, synthetic resins, acrylic oligomers, glass fibers, glass beads, etc. Good. Moreover, it is good also as an adhesive agent which contains microparticles | fine-particles and shows light diffusibility.

  In the production method of the present invention, the surface protective sheet is preferably a sheet containing a resin having excellent mechanical strength and excellent heat resistance, for example. Examples of the resin include polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as diacetyl cellulose and triacetyl cellulose, acrylic polymers such as polymethyl acrylate and polymethyl methacrylate, polystyrene, acrylonitrile and styrene. Examples thereof include styrene polymers such as polymers (AS resins) and polycarbonate polymers. Polyethylene, polypropylene, polyolefin having a cyclo or norbornene structure, polyolefin polymer such as ethylene / propylene copolymer, vinyl chloride polymer, nylon, aromatic polyamide polymer, imide polymer, sulfone polymer, polyether sulfone Examples thereof include a polymer, a polyether ether ketone polymer, a vinylidene chloride polymer, a vinyl alcohol polymer, a vinyl butyral polymer, an arylate polymer, a polyoxymethylene polymer, an epoxy polymer, or a blend of the aforementioned polymers. Of these, polyesters such as polyethylene terephthalate and polyethylene naphthalate are preferred.

  Next, in the cut surface of the laminated polarizing plate of the present invention, the protrusion is preferably 10 μm or less, and the length of the protrusion is preferably 50 μm or less, more preferably the protrusion is 5 μm or less. Yes, the length of the protrusion is 30 μm or less, and the most preferable is the absence of bumps and protrusions (below the measurement limit). In addition, the length of the said protrusion and protrusion can be measured by the method described in the below-mentioned Example, for example.

  Next, the image display apparatus of the present invention will be described. The image display device of the present invention has an image display element and the laminated polarizing plate of the present invention, and the laminated polarizing plate is disposed at a certain distance from the image display element. is there. It is preferable that nothing exists between the image display element and the laminated polarizing plate, that is, a gap. As the image display element, a liquid crystal cell is preferable, but the present invention is not limited to this. For example, self-luminous light such as an organic electroluminescence (EL) display, a plasma display panel (PDP), and a field emission display (FED). It can also be used for type display devices. Examples of the liquid crystal display device include a liquid crystal display device for a viewfinder of a video camera and a digital camera, and a liquid crystal display device for a projector.

  An example of the liquid crystal display device of the present invention is shown in the sectional view of FIG. As shown in the figure, this apparatus includes a liquid crystal cell 31 and the laminated polarizing plate 32 of the present invention, and the liquid crystal cell 31 and the laminated polarizing plate 32 are separated from each other. Is a laminate of a polarizing plate 303 and a resin film 302. An arrow 300 in the figure indicates the eyepiece direction.

  The type of the liquid crystal cell forming the liquid crystal display device can be arbitrarily selected. For example, it is represented by an active matrix driving type represented by a thin film transistor type, a twisted nematic (TN) type, or a super twisted nematic (STN) type. Various types of liquid crystal cells such as simple matrix drive type can be used. Among these, the laminated polarizing plate of the present invention is particularly preferably used for TN cells, VA (Vertical Alignment) cells, OCB (Optically Aligned Birefringence) cells, and IPS (In Plane Switching) cells.

  In addition, the liquid crystal cell has a structure in which liquid crystal is usually injected into a gap between opposing liquid crystal cell substrates, and the liquid crystal cell substrate is not particularly limited, and for example, a glass substrate or a plastic substrate can be used. The material for the plastic substrate is not particularly limited, and conventionally known materials can be used.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. However, the present invention is not limited to the following examples. The characteristics of the laminated polarizing plate were evaluated by the following methods.

(1) Measurement of the raised surface of the cut surface For the 10 mm × 11 mm laminated polarizing plate, the thickness of the central portion and the vicinity of the cut surface was measured with a micrometer, and the difference was taken as the raised shape.

(2) Measurement of protrusion on cut surface Using a laser microscope or an optical microscope, the length of the protrusion generated on the cut surface (a, b in FIG. 1) of the laminated polarizing plate is observed from above and measured. did.

(3) Measurement of surface contamination The polarizing plate side surface and the resin film side surface of the laminated polarizing plate were observed visually. And the thing with a dirt was evaluated as "x", and the thing without a dirt was evaluated as "(circle)".

(Preparation of polarizing film)
First, a polyvinyl alcohol film (thickness 80 μm) was stretched 5 times in an aqueous iodine solution and dried to prepare a polarizer. Subsequently, a UV urethane hard coat layer having a reflectance of 1% or less and a physical optical thin film (AR layer) were formed in this order on one side of a triacetyl cellulose film (TAC film). Then, the treated TAC film was laminated on one side of the polarizer, and the untreated TAC film was laminated on the other side of the polarizer via an adhesive, respectively, to produce a polarizing film (thickness: 195 μm, Light transmittance 45%).

(Production of resin film)
100 parts by weight of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 120 parts by weight of methyltetrahydrophthalic anhydride as a curing agent, and tetra-n-butylphosphonium O, O-diethyl phosphoroyl as a curing accelerator 2 parts by weight of dithioate was added to each, and mixed by stirring, and a prefilm was formed using a casting method. Further, the prefilm was thermally cured at 180 ° C. for 30 minutes to produce an epoxy film (thickness 700 μm, 380 mm × 280 mm). Subsequently, an acrylic urethane UV resin was applied to one side of the epoxy film to form a protective layer (thickness 3 μm), thereby obtaining a resin film. The light transmittance of this resin film was 91.7%, and the glass transition temperature was 180 ° C.

(Adhesive preparation)
100 parts by weight of butyl acrylate, 5.0 parts by weight of acrylic acid, 0.075 parts by weight of 2-hydroxyethyl acrylate, 0.3 parts by weight of azobisisonitrile and 250 parts by weight of ethyl acetate are mixed and stirred. However, the reaction was carried out at about 60 ° C. for 6 hours to obtain an acrylic polymer solution having a weight average molecular weight of 1,630,000. In the acrylic polymer solution, 0.6 parts by weight of an isocyanate polyfunctional compound (trade name Coronate L; manufactured by Nippon Polyurethane Industry) and a silane coupling agent (trade name KBM403) with respect to 100 parts by weight of the polymer solid content. ; Manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.08 part by weight were added to prepare an adhesive solution. The 90 ° peel peel strength of the obtained adhesive solution was 10 N / 25 mm.

(Surface protection sheet production)
On the PET film (thickness 50 micrometers), the said adhesive was apply | coated so that it might become thickness 10 micrometers, and it was made to dry, and the surface protection sheet was obtained.

(Laminate production)
The untreated TAC film side of the polarizing plate was bonded to the epoxy film side of the resin film via the adhesive (thickness 23 μm). The said surface protection sheet was bonded together by the said adhesive on both surfaces of this laminated body.

(Cutting method)
A dicing tape (thickness 170 μm, trade name ELEP Holder NBD5170K; manufactured by Nitto Denko Corporation) was attached to the treated TAC film side of the polarizing plate of the laminate, and the dicing tape side was mounted on a dicing fixture.

  Next, using a dicer (DAD341 dicer; manufactured by Disco) and a grindstone (blade, thickness 0.15 mm, trade name Z1100LS3 # 600; manufactured by Disco) under the conditions of a rotational speed of 20000 rpm and a speed of 10 mm / sec. Then, the laminate was cut. In addition, the dicing tape located under the said laminated body cut | disconnected to 100 micrometers among thickness 170 micrometers. Then, about 110 10 mm × 11 mm laminated polarizing plates were produced from the 150 mm × 150 mm laminated body.

(Washing and UV irradiation method)
The laminated polarizing plate cut on the dicing tape is subjected to spinner cleaning (DCS140; manufactured by Disco Corporation), and then irradiated with black light from the dicing tape side for 2 minutes to obtain the laminated polarizing plate and the dicing tape. The laminated polarizing plate was finally peeled from the dicing tape.

  Using a dicer (DFD651 dicer; manufactured by Disco) and a grindstone (blade, thickness 200 μm, trade name Z1110LS3 # 400; manufactured by Disco), cutting the laminate under the conditions of a rotational speed of 50000 rpm and a speed of 100 mm / sec. A laminated polarizing plate was produced in the same manner as in Example 1 except that the above was performed.

  Using a dicer (DFD651 dicer; manufactured by Disco) and a grindstone (blade, thickness 200 μm, trade name Z1110LS3 # 400; manufactured by Disco), the thickness of the resin film is 300 μm, and the rotational speed is 50000 rpm and the speed is 150 mm / second. A laminated polarizing plate was produced in the same manner as in Example 1 except that the laminate was cut twice on the same line under the above conditions. In the same cutting twice, the first cutting depth and the second cutting depth were both set to the depth of cutting the dicing tape by 50 μm. Further, the cutting order was the order of X-axis direction → Y-axis direction → X-axis direction → Y-axis direction. The X-axis direction is a polarization axis or an absorption axis, and the Y-axis direction is a direction perpendicular to the X-axis direction.

  A laminated polarizing plate was produced in the same manner as in Example 1 except that a commercially available acrylic plate (thickness 1 mm, trade name Acrylite; manufactured by Mitsubishi Rayon Co., Ltd.) was used as the resin film. The commercially available acrylic plate had a light transmittance of 93% and a glass transition temperature of 105 ° C.

(Comparative Example 1)
A laminated polarizing plate was produced in the same manner as in Example 1 except that a PET film (thickness 38 μm) (trade name T-600; manufactured by Mitsubishi Chemical Corporation) was used instead of the epoxy resin film. The PET film had a light transmittance of 92% and a glass transition temperature of 90 ° C.

(Comparative Example 2)
A laminated polarizing plate was produced in the same manner as in Example 1 except that the laminate was cut using a CO ₂ laser (trade name LC-100A; manufactured by Roland) instead of the dicer. . In addition, the said cutting | disconnection was performed by irradiating a laser twice with 25W and the cutting speed of 60 mm / sec.

  With respect to the laminated polarizing plates obtained in Examples 1 to 4 and Comparative Examples 1 and 2, the ridges of the end surfaces (cut surfaces) and the lengths of the protrusions were measured. The results are shown in Table 1 below. As shown in Table 1 below, in Examples 1 to 4, compared to Comparative Examples 1 and 2, the bulge of the cut surface and the generation of protrusions on the cut surface could be reduced. In all the examples, there was no surface contamination, but in Comparative Example 2 which was laser cut, surface contamination occurred.

(Table 1)
Bump of cut surface (μm) Length of protrusion (μm) Surface contamination Example 1 <5 10 ○
Example 2 <525
Example 3 <520
Example 4 <530
Comparative Example 1 10 100 ○
Comparative Example 2 35 70 ×

  According to the manufacturing method of the present invention, it is possible to suppress the rise of the cut surface and the generation of protrusions on the cut surface, and it is possible to obtain a self-supporting laminated polarizing plate having sufficient rigidity. The laminated polarizing plate obtained by the production method of the present invention can be applied to any image display device, and among them, a liquid crystal display device for a viewfinder such as a video camera or a digital camera, and a liquid crystal display device for a projector. Are preferably used.

It is a top view which shows an example of the laminated polarizing plate of this invention. It is sectional drawing which shows an example of the liquid crystal display device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 Laminated polarizing plate 22 Surface protection sheet 31 Liquid crystal cell 32 Laminated polarizing plate 302 Resin film 303 Polarizing plate 300 Eyepiece direction A Vertical axis B Absorption axis

Claims (21)

  A method for producing a laminated polarizing plate, comprising a step of laminating a polarizing plate film and a resin film having a light transmittance of 80% or more and a glass transition temperature of 100 ° C. or more to form a laminate film. And a dicer cutting step of dicing the laminate film to divide the laminate film into laminated polarizing plates.   The resin film is an epoxy resin, polyimide resin, polyester resin, acrylic resin, methacrylic resin, polycarbonate (PC) resin, polyethylene naphthalate (PEN) resin, polyethylene terephthalate (PET) resin, 2. The resin composition comprises at least one resin selected from the group consisting of acetylcellulose (TAC), norbornene resin, polyetherimide resin, polyamide resin, polysulfone resin, polyphenylene sulfide resin, and polyethersulfone resin. The manufacturing method as described.   The manufacturing method according to claim 1, wherein the resin film is at least one of an epoxy resin film and an acrylic resin film.   The manufacturing method according to claim 1, wherein the phase difference of the resin film is 5 nm or less.   The light transmittance of the said resin film is the range of 80 to 100%, The manufacturing method in any one of Claim 1 to 4.   The manufacturing method according to any one of claims 1 to 5, wherein a glass transition temperature of the resin film is in a range of 100 to 400 ° C.   The manufacturing method according to claim 1, wherein the resin film has a thickness in a range of 0.05 to 1.5 mm.   The manufacturing method according to claim 1, wherein in the dicer cutting step, the cutting direction is at least one of a polarization axis direction and an absorption axis direction in the polarizing film.   The dicer cutting conditions in the dicer cutting step are selected from the group consisting of a dicing blade thickness of 30 to 1000 μm, a dicing blade roughness # 200 to # 1000, a dicing blade rotation speed of 10,000 to 60000 rpm, and a dicing speed of 10 to 300 mm / sec. The production method according to claim 1, wherein the at least one condition is satisfied.   The manufacturing method according to any one of claims 1 to 9, wherein in the dicer cutting step, the laminate film is fixed to a dicing apparatus with an adhesive sheet, and the dicer is cut in this state.   The manufacturing method according to claim 1, wherein in the dicer cutting step, dicer cutting is performed in accordance with the shape and size of an image display device in which the laminated polarizing plate is used.   The manufacturing method according to claim 11, wherein the image display device is a viewfinder liquid crystal display device or a projector liquid crystal display device.   It is a laminated polarizing plate by which the polarizing plate and the resin film were laminated | stacked, Comprising: The laminated polarizing plate manufactured by the method in any one of Claims 1-12.   The laminated polarizing plate according to claim 13, wherein the cut surface has a raised portion of 10 μm or less.   The multilayer polarizing plate according to claim 13 or 14, wherein the length of the protrusion on the cut surface is 50 µm or less.   The multilayer polarizing plate according to any one of claims 13 to 15, which is used for a viewfinder liquid crystal display device or a projector liquid crystal display device.   An image display device including an image display element and a polarizing plate, wherein the polarizing plate is the laminated polarizing plate according to any one of claims 13 to 15, and the laminated polarizing plate is the image display element. And an image display device arranged at a certain distance.   The image display device according to claim 17, wherein a gap is provided between the image display element and the eccentric plate.   The image display device according to claim 17 or 18, wherein the image display element is a liquid crystal cell.   The image display device according to claim 19, which is for a viewfinder or a projector.   The image display device according to claim 20, wherein the viewfinder is a viewfinder of a video camera or a digital camera.

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