Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
  • B32B7/02—Physical, chemical or physicochemical properties
  • B32B7/023—Optical properties
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B9/00—Layered products comprising a layer of a particular substance not covered by groups B32B11/00 - B32B29/00
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/30—Polarising elements
• • G—PHYSICS
  • G02—OPTICS
  • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
  • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
  • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
  • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
  • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
  • G02F1/1333—Constructional arrangements; Manufacturing methods
  • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
  • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B33/00—Electroluminescent light sources
  • H05B33/02—Details
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B33/00—Electroluminescent light sources
  • H05B33/12—Light sources with substantially two-dimensional [2D] radiating surfaces
  • H05B33/14—Light sources with substantially two-dimensional [2D] radiating surfaces characterised by the chemical or physical composition or the arrangement of the electroluminescent material, or by the simultaneous addition of the electroluminescent material in or onto the light source
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
  • H10K59/80—Constructional details
  • H10K59/87—Passivation; Containers; Encapsulations
  • H10K59/871—Self-supporting sealing arrangements
  • H10K59/8722—Peripheral sealing arrangements, e.g. adhesives, sealants
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
  • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
  • H10K59/80—Constructional details
  • H10K59/8791—Arrangements for improving contrast, e.g. preventing reflection of ambient light

Definitions

• the present invention relates to a circularly polarizing film laminate with an adhesive layer and an image display device.
• the optical laminate having a polarizing film constituting the image display device as described above is obtained by bonding a retardation film to a polarizing film in which protective films such as triacetyl cellulose are bonded adjacent to both sides of the polarizing film.
• a protective film is attached adjacent to one surface of the polarizing film and adjacent to the other surface of the polarizing film. It is disclosed that a mode (polarizing plate with a retardation layer) in which a retardation film is attached to the substrate is useful (Patent Documents 2 to 7).
• JP 2016-136181 A Japanese Patent Application Laid-Open No. 2020-64290 Japanese Patent Application Laid-Open No. 2020-64291 Japanese Patent Application Laid-Open No. 2020-64292 JP 2020-64293 A Japanese Patent Application Laid-Open No. 2020-76968 JP 2020-76939 A
• the above polarizing plate with a retardation layer is required to be circularly polarized light.
• an object of the present invention is to provide a circularly polarizing film laminate with an adhesive layer that can suppress changes in reflectance in a hot and humid environment.
• the present invention provides circularly polarized light in which a first transparent protective film is attached to one surface of a polarizing film via an adhesive layer, and a retardation film is attached to the other surface of the polarizing film via an adhesive layer.
• the present invention relates to a layered circularly polarizing film laminate.
• the present invention relates to an image display device comprising the circularly polarizing film laminate with the pressure-sensitive adhesive layer.
• the first transparent protective film is attached to one side of the polarizing film via an adhesive layer
• the retardation film is attached to the other side of the polarizing film with an adhesive layer.
• a circularly polarizing film laminate bonded via and a circularly polarizing film laminate with an adhesive layer having an adhesive layer on the retardation film side of the circularly polarizing film laminate, and the single transmittance is 41% or more 42 .5% or less.
• the pressure-sensitive adhesive layer-attached circularly polarizing film laminate of the present invention by setting the single transmittance within a certain range, a certain concentration of the iodine complex in the polarizing film is maintained even in a wet and hot environment, and changes in reflectance can be suppressed. .
• the first transparent protective film is attached to one side of the polarizing film via an adhesive layer
• the retardation film is attached to the other side of the polarizing film with an adhesive layer.
• a pressure-sensitive adhesive layer on the retardation film side of the circularly polarizing film laminate, and the single transmittance is 41% or more and 42.5% or less.
• the polarizing film is formed by adsorbing and aligning a dichroic substance such as iodine or a dichroic dye on a polyvinyl alcohol film. From the viewpoint of the initial polarizing performance of the polarizing film, the polarizing film is preferably an iodine-based polarizing film containing iodine as the dichroic substance.
• the polyvinyl alcohol (PVA)-based film has translucency in the visible light region, and can be used without particular limitation if it disperses and adsorbs dichroic substances such as iodine and dichroic dyes.
• the material for the polyvinyl alcohol-based film include polyvinyl alcohol and its derivatives.
• Derivatives of polyvinyl alcohol include, for example, polyvinyl formal and polyvinyl acetal; olefins such as ethylene and propylene; unsaturated carboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, and those modified with alkyl esters thereof, acrylamide and the like; is mentioned.
• the polyvinyl alcohol preferably has an average degree of polymerization of about 100 to 10,000, more preferably about 1,000 to 10,000, even more preferably about 1,500 to 4,500. .
• the polyvinyl alcohol preferably has a degree of saponification of about 80 to 100 mol %, more preferably about 95 mol % to 99.95 mol.
• the average degree of polymerization and the degree of saponification can be determined according to JIS K 6726.
• the polarizing film may contain a water-soluble radical scavenger from the viewpoint of suppressing changes in reflectance in a high-temperature environment.
• the water-soluble radical scavenger is preferably a compound that can dissolve at least 1 part by weight in 100 parts by weight of water at 25°C, from the viewpoint of easily migrating to water in the polarizing film. It is more preferable to be a compound that can dissolve 2 parts by weight or more per part, and more preferably a compound that can dissolve 5 parts by weight or more per 100 parts by weight of water at 25°C.
• the water-soluble radical scavengers may be used alone or in combination of two or more.
• the water-soluble radical scavenger can suppress changes in transmittance and reflectance due to coloring of polyvinyl alcohol, which is the main component of the polarizing film, in a high-temperature environment.
• the water-soluble radical scavenger include hindered phenol-based, hindered amine-based, phosphorus-based, sulfur-based, benzotriazole-based, benzophenone-based, hydroxylamine-based, salicylic acid ester-based, and triazine-based compounds.
• a compound having a function can be mentioned.
• the water-soluble radical scavenger is preferably a compound having a nitroxy radical or a nitroxide group, for example.
• an N-oxyl compound (as a functional group, C--N(--C)--O . ) from the viewpoint of having a relatively stable radical in the air at room temperature.
• O. represents an oxy radical
• N-oxyl compounds include compounds having an organic group having the following structure.
• R 1 represents an oxy radical
• R 2 to R 5 independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms
• n represents 0 or 1.
• the left side of the dotted line indicates an arbitrary organic group.
• the water-soluble radical scavenger preferably has a molecular weight of 1,000 or less, more preferably 500 or less, and 300 or less, from the viewpoint of efficiently capturing radicals generated in the polarizing film. is more preferred.
• the content of the water-soluble radical scavenger is 0.005% by weight or more from the viewpoint of suppressing changes in reflectance in a high-temperature environment. preferably 0.01% by weight or more, more preferably 0.1% by weight or more, and preferably 10% by weight or less, and 5% by weight or less is more preferable, and 2% by weight or less is even more preferable.
• the content of boron in the polarizing film is preferably 3.5% by weight or more, more preferably 4% by weight or more, in the polarizing film from the viewpoint of suppressing change in reflectance in a moist and hot environment. is more preferable, and from the viewpoint of suppressing cracking of the polarizing film in a high-temperature environment, it is preferably 5.2% by weight or less, more preferably 4.9% by weight or less, in the polarizing film. .
• the content of potassium in the polarizing film is preferably 0.3% by weight or more from the viewpoint of suppressing a change in reflectance in a moist and heat environment, and is 0.35% by weight or more. From the viewpoint of suppressing the reflection hue change in a high-temperature environment, it is preferably 0.8% by weight or less, more preferably 0.6% by weight or less, in the polarizing film. .
• the polarizing film is obtained by a conventional method for producing a polarizing film, for example, by subjecting the polyvinyl alcohol film to any swelling step and washing step, and at least a dyeing step, a cross-linking step, and a stretching step.
• the polarizing film contains the water-soluble radical scavenger
• the treatment bath in any one or more of the swelling step, the washing step, the dyeing step, the cross-linking step, and the stretching step is , as long as it contains a water-soluble radical scavenger.
• the polarizing film preferably has a thickness of 1 ⁇ m or more, more preferably 2 ⁇ m or more, from the viewpoint of improving the initial degree of polarization of the polarizing film. It is preferably 20 ⁇ m or less from the viewpoint of suppressing polyene formation in the lower layer.
• a polarizing film having a thickness of about 8 ⁇ m or less a laminate containing a polyvinyl alcohol-based resin layer formed on a thermoplastic resin substrate is used as the polyvinyl alcohol-based film, and the following thin film is used.
• a method for manufacturing a polarizing film can be applied.
• a polarizing film (thin polarizing film) is obtained by a conventional method for manufacturing a polarizing film.
• the polarizing film contains the water-soluble radical scavenger, any one or more of the insolubilizing treatment step, the cross-linking treatment step, the washing treatment step, the dyeing treatment step, and the underwater stretching treatment step
• the treatment bath in the treatment step may contain the water-soluble radical scavenger.
• the first transparent protective film is not particularly limited, and various transparent protective films used for polarizing films can be used.
• a material constituting the transparent protective film for example, a thermoplastic resin that is excellent in transparency, mechanical strength, thermal stability, water barrier property, isotropy, etc. is used.
• the thermoplastic resin include cellulose ester-based resins such as triacetyl cellulose, polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate, polyethersulfone-based resins, polysulfone-based resins, polycarbonate-based resins, nylon and aromatic resins.
• Polyamide resins such as group polyamides, polyimide resins, polyolefin resins such as polyethylene, polypropylene, ethylene/propylene copolymers, (meth)acrylic resins, cyclic polyolefin resins having a cyclo or norbornene structure (norbornene resins ), polyarylate-based resins, polystyrene-based resins, polyvinyl alcohol-based resins, and mixtures thereof.
• the transparent protective film may be a cured layer formed from thermosetting resins such as (meth)acrylic, urethane, acrylic urethane, epoxy, and silicone or ultraviolet curable resins.
• cellulose ester-based resins polycarbonate-based resins, (meth)acrylic-based resins, cyclic polyolefin-based resins, and polyester-based resins are suitable.
• the transparent protective film contains any appropriate additives such as ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, anti-coloring agents, flame retardants, antistatic agents, pigments, colorants, and the like. You can
• the first transparent protective film is typically arranged on the viewing side of the image display device, as will be described later. Therefore, other layers such as a hard coat layer, an anti-sticking layer, a diffusion layer or an anti-glare layer can be provided on the surface of the first transparent protective film on which the polarizing film is not adhered. In addition, the above other layer can be provided on the protective film itself, or can be provided separately from the protective film.
• the thickness of the first transparent protective film can be determined as appropriate, but in general, it is preferably about 1 to 200 ⁇ m from the viewpoint of strength, workability such as handleability, and thin layer properties. It is more preferably about 100 ⁇ m, more preferably about 10 to 50 ⁇ m.
• the first transparent protective film preferably has a moisture permeability of 1 g/(m 2 ⁇ 24 h) or more, and 2 g/(m 2 ⁇ 24 h) or more, and from the viewpoint of durability in a moist and heat environment, the moisture permeability is preferably 1000 g / (m 2 ⁇ 24 h) or less, and 600 g / (m 2 ⁇ 24 h) or less It is more preferable to have
• the moisture permeability was determined according to the moisture permeability test (cup method) of JIS Z0208, a sample cut to 60 mm in diameter was set in a moisture permeability cup containing about 15 g of calcium chloride, and the temperature was 40°C and the humidity was 90% RH. H. It can be calculated by measuring the weight increase of calcium chloride before and after it is placed in a constant temperature machine and left for 24 hours.
• the retardation film includes, for example, a film produced by stretching and orienting a polymer film, a film in which a liquid crystal material is oriented and fixed, and the like, and suppresses the change in retardation in a high temperature and moist heat environment. From the viewpoint of this, it is preferable to have a retardation layer, which is an alignment fixed layer of a liquid crystal compound, and a second transparent protective film. As will be described later, the retardation film is typically arranged on the image display cell side of the image display device.
• the second transparent protective film may be the same as the first transparent protective film, but is preferably optically isotropic from the viewpoint of reducing the viewing angle dependence of antireflection. .
• “Optically isotropic” means that the in-plane retardation Re(550) is 0 nm to 10 nm and the thickness direction retardation Rth(550) is ⁇ 10 nm to +10 nm.
• the thickness of the second transparent protective film can be determined as appropriate, but in general, it is preferably about 1 to 200 ⁇ m from the viewpoint of strength, workability such as handleability, thin layer property, etc. It is more preferably about 100 ⁇ m, more preferably about 10 to 50 ⁇ m.
• the second transparent protective film preferably has a moisture permeability of 100 g/(m 2 ⁇ 24 h) or more, more preferably 200 g/(m 2 ⁇ 24 h) or more, from the viewpoint of production efficiency in the drying process after bonding. is more preferable.
• the fixed alignment layer of the liquid crystal compound is a layer in which the liquid crystal compound is aligned in a predetermined direction in the layer and the alignment state is fixed. It is an encompassing concept.
• liquid crystal compound examples include liquid crystal compounds whose liquid crystal phase is a nematic phase (nematic liquid crystal).
• a liquid crystal compound for example, a liquid crystal polymer or a liquid crystal monomer can be used. Either lyotropic or thermotropic mechanism may be used to develop the liquid crystallinity of the liquid crystal compound.
• the liquid crystal polymer and liquid crystal monomer may be used alone or in combination.
• the liquid crystal monomer is preferably a polymerizable monomer and/or a crosslinkable monomer from the viewpoint that the alignment state of the liquid crystal monomer can be fixed by polymerizing or cross-linking the liquid crystal monomer.
• a polymer is formed by polymerization and a three-dimensional network structure is formed by cross-linking, but these are non-liquid crystalline. Therefore, the formed retardation layer does not undergo a transition to a liquid crystal phase, a glass phase, or a crystal phase due to a change in temperature, which is peculiar to liquid crystalline compounds. As a result, the retardation layer becomes a highly stable retardation layer that is not affected by temperature changes.
• the temperature range in which the liquid crystal monomer exhibits liquid crystallinity varies depending on the type.
• the temperature range is preferably 40°C to 120°C, more preferably 50°C to 100°C, most preferably 60°C to 90°C.
• any suitable liquid crystal monomer is adopted, for example, JP-T-2002-533742 (WO00/37585), EP358208 (US5211877), EP66137 (US4388453), WO93/22397, EP0261712, DE19504224, DE4408171, and Polymerizable mesogenic compounds described in GB2280445 and the like can be used.
• Specific examples of such polymerizable mesogenic compounds include LC242 (trade name) available from BASF, E7 (trade name) available from Merck, and LC-Sillicon-CC3767 (trade name) available from Wacker-Chem.
• a nematic liquid crystal monomer is preferable as the liquid crystal monomer.
• the alignment fixed layer of the liquid crystal compound is formed by subjecting the surface of a predetermined substrate to an alignment treatment, coating the surface with a coating liquid containing a liquid crystal compound, and orienting the liquid crystal compound in the direction corresponding to the alignment treatment. , can be formed by fixing the orientation state.
• orientation treatment Any suitable orientation treatment may be employed as the orientation treatment, and specific examples include mechanical orientation treatment, physical orientation treatment, and chemical orientation treatment. Specific examples of mechanical orientation treatment include rubbing treatment and stretching treatment. Specific examples of physical orientation treatment include magnetic orientation treatment and electric field orientation treatment. Specific examples of chemical alignment treatment include oblique vapor deposition and photo-alignment treatment. Arbitrary appropriate conditions can be adopted as the processing conditions for various alignment treatments depending on the purpose.
• the alignment of the liquid crystal compound is carried out by treating it at a temperature that exhibits a liquid crystal phase depending on the type of liquid crystal compound. By performing such a temperature treatment, the liquid crystal compound assumes a liquid crystal state, and the liquid crystal compound is aligned in accordance with the orientation treatment direction of the surface of the base material.
• the alignment state is fixed, for example, by cooling the aligned liquid crystal compound.
• the orientation state is fixed by subjecting the oriented liquid crystal compound to a polymerization treatment or a crosslinking treatment.
• the liquid crystal compound and a method for forming the alignment fixed layer for example, the method described in JP-A-2006-163343 can be used as a reference.
• the alignment fixed layer a form in which the discotic liquid crystal compound is aligned in any one of vertical alignment, hybrid alignment, and tilt alignment can be mentioned.
• the discotic plane of the discotic liquid crystal compound is oriented substantially perpendicular to the film plane of the retardation layer.
• the average angle between the film surface and the disk surface of the discotic liquid crystal compound is preferably 70° to 90°, more preferably 80° to 90°. , more preferably 85° to 90°.
• Discotic liquid crystal compounds generally have a cyclic mother nucleus such as benzene, 1,3,5-triazine, or calixarene at the center of the molecule, and a linear alkyl group, alkoxy group, or substituted benzoyl A liquid crystal compound having a discotic molecular structure in which oxy groups and the like are radially substituted as side chains.
• Representative examples of discotic liquid crystals include C.I. Destrade et al., Mol. Cryst. Liq. Cryst. 71, 111 (1981), benzene derivatives, triphenylene derivatives, truxene derivatives and phthalocyanine derivatives; Kohne et al., Angew. Chem.
• discotic liquid crystal compounds include compounds described in JP-A-2006-133652, JP-A-2007-108732, and JP-A-2010-244038.
• the retardation layer may be a single layer of an alignment fixed layer of a liquid crystal compound.
• the thickness thereof is preferably 0.5 ⁇ m to 7 ⁇ m, more preferably 1 ⁇ m to 5 ⁇ m.
• a retardation layer is typically provided to impart antireflection properties to a polarizing plate, and can function as a ⁇ /4 plate when the retardation layer is a single layer of an orientation-fixed layer.
• the in-plane retardation Re(550) of the retardation layer is preferably 100 nm to 190 nm, more preferably 110 nm to 170 nm, still more preferably 130 nm to 160 nm.
• the retardation layer may exhibit a reverse wavelength dispersion characteristic in which the retardation value increases according to the wavelength of the measurement light, or exhibits a positive wavelength dispersion characteristic in which the retardation value decreases according to the wavelength of the measurement light. Alternatively, it may exhibit a flat wavelength dispersion characteristic in which the retardation value hardly changes even with the wavelength of the measurement light.
• the angle ⁇ between the slow axis of the retardation layer and the absorption axis of the polarizing film is preferably 40° to 50°, more preferably 42° to 48°, and still more preferably about 45°. . If the angle ⁇ is within such a range, a circularly polarizing film laminate having excellent circularly polarizing properties can be obtained.
• the retardation layer may have a laminated structure of a first orientation fixed layer and a second orientation fixed layer.
• one of the first fixed orientation layer and the second fixed orientation layer can function as a ⁇ /4 plate, and the other can function as a ⁇ /2 plate. Therefore, the thicknesses of the first alignment fixed layer and the second alignment fixed layer can be adjusted so as to obtain the desired in-plane retardation of the ⁇ /4 plate or the ⁇ /2 plate.
• the thickness of the first oriented fixed layer is, for example, 2.0 ⁇ m to 3 ⁇ m.
• the thickness of the second alignment fixed layer is, for example, 1.0 ⁇ m to 2.0 ⁇ m.
• the in-plane retardation Re(550) of the first alignment fixed layer is preferably 200 nm to 300 nm, more preferably 230 nm to 290 nm, still more preferably 250 nm to 280 nm.
• the in-plane retardation Re(550) of the second textured fixed layer is as described above for the single-layer textured fixed layer.
• the angle formed by the slow axis of the first alignment fixed layer and the absorption axis of the polarizing film is preferably 10° to 20°, more preferably 12° to 18°, still more preferably about 15°. be.
• the angle formed by the slow axis of the second alignment fixed layer and the absorption axis of the polarizing film is preferably 70° to 80°, more preferably 72° to 78°, still more preferably about 75°. be. With such a configuration, it is possible to obtain characteristics close to ideal reverse wavelength dispersion characteristics, and extremely excellent antireflection characteristics can be realized.
• the liquid crystal compounds constituting the first alignment fixed layer and the second alignment fixed layer, the method for forming the first alignment fixed layer and the second alignment fixed layer, the optical characteristics, etc. are described above for the single-layer alignment fixed layer. As explained in
• ⁇ Adhesive layer> The first transparent protective film and the retardation film are attached to the polarizing film via an adhesive layer.
• various adhesives used in polarizing films can be applied.
• examples include isocyanate adhesives, polyvinyl alcohol adhesives, gelatin adhesives, vinyl latex adhesives, water-based polyester and the like. These adhesives are usually used as adhesives consisting of an aqueous solution (water-based adhesives) and contain 0.5 to 60% by weight of solids.
• polyvinyl alcohol-based adhesives are preferable, and acetoacetyl group-containing polyvinyl alcohol-based adhesives are more preferable.
• the water-based adhesive may contain a cross-linking agent.
• a cross-linking agent a compound having at least two functional groups in one molecule that are reactive with components such as polymers constituting the adhesive is usually used. Examples include alkylenediamines; isocyanates; epoxies; Aldehydes: amino-formaldehydes such as methylol urea and methylol melamine.
• the amount of the cross-linking agent compounded in the adhesive is usually about 10 to 60 parts by weight per 100 parts by weight of components such as polymers constituting the adhesive.
• examples of the adhesive include active energy ray-curable adhesives such as UV-curable adhesives and electron beam-curable adhesives.
• active energy ray-curable adhesive include (meth)acrylate adhesives.
• examples of the curable component in the (meth)acrylate adhesive include a compound having a (meth)acryloyl group and a compound having a vinyl group.
• examples of compounds having a (meth)acryloyl group include alkyl (meth)acrylates having 1 to 20 carbon atoms, chain alkyl (meth)acrylates, alicyclic alkyl (meth)acrylates, and polycyclic alkyl (meth)acrylates.
• (Meth)acrylate adhesives include hydroxyethyl (meth)acrylamide, N-methylol (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-ethoxymethyl (meth)acrylamide, (meth)acrylamide, (meth) Nitrogen-containing monomers such as acryloylmorpholine may also be included.
• (Meth)acrylate-based adhesives contain tripropylene glycol diacrylate, 1,9-nonanediol diacrylate, tricyclodecanedimethanol diacrylate, cyclic trimethylolpropane formal acrylate, dioxane glycol diacrylate, and EO as crosslinking components.
• a polyfunctional monomer such as modified diglycerin tetraacrylate may be included.
• a compound having an epoxy group or an oxetanyl group can also be used as a cationic polymerization-curable adhesive.
• the compound having an epoxy group is not particularly limited as long as it has at least two epoxy groups in the molecule, and various commonly known curable epoxy compounds can be used.
• the adhesive may contain appropriate additives as necessary.
• the additives include silane coupling agents, coupling agents such as titanium coupling agents, adhesion promoters such as ethylene oxide, ultraviolet absorbers, deterioration inhibitors, dyes, processing aids, ion trapping agents, and antioxidants. agents, tackifiers, fillers, plasticizers, leveling agents, foaming inhibitors, antistatic agents, heat stabilizers, hydrolysis stabilizers, and the like.
• the adhesive may be applied to any of the first transparent protective film, the retardation film side, and the polarizing film side, or may be applied to both. After lamination, a drying process is performed to form an adhesive layer consisting of a coated dry layer. After the drying step, ultraviolet rays or electron beams can be applied, if necessary.
• the thickness of the adhesive layer is not particularly limited, and when a water-based adhesive or the like is used, it is preferably about 30 to 5000 nm, more preferably about 100 to 1000 nm. When using an electron beam curing adhesive or the like, the thickness is preferably about 0.1 to 100 ⁇ m, more preferably about 0.5 to 10 ⁇ m.
• the circularly polarizing film laminate may further include other retardation layers.
• Other optical properties of the retardation layer for example, refractive index properties, in-plane retardation, Nz coefficient, photoelastic coefficient), thickness, arrangement position, etc. can be appropriately set according to the purpose.
• the adhesive layer-attached circularly polarizing film laminate of the present invention has an adhesive layer on the retardation film side of the circularly polarizing film laminate.
• the adhesive layer-attached circularly polarizing film laminate has a single transmittance of 41% or more and 42.5% or less.
• the adhesive layer-attached circularly polarizing film laminate preferably has a single transmittance of 41% or more, more preferably 41.2% or more, from the viewpoint of suppressing changes in reflectance in a high-temperature environment.
• the single transmittance is preferably 42.5% or less, more preferably 42.3% or less, and 42.1% or less. is more preferable.
• the single transmittance was measured using a spectrophotometer with an integrating sphere (for example, product name: V7100, manufactured by JASCO Corporation) with a JIS Z8701 2-degree field of view (C light source) and corrected for visibility. Y value.
• an integrating sphere for example, product name: V7100, manufactured by JASCO Corporation
• JIS Z8701 2-degree field of view C light source
• the total thickness including from the polarizing film to the adhesive layer is 30 ⁇ m or more from the viewpoint of reducing the occurrence rate of appearance defects (such as cracks) that occur during handling work. It is preferably 50 ⁇ m or more, more preferably 50 ⁇ m or more, and preferably 150 ⁇ m or less, more preferably 100 ⁇ m or less from the viewpoint of antireflection in a high-temperature environment.
• Adhesive layer As the adhesive that forms the adhesive layer, various adhesives used in polarizing films can be applied. Alkyl ether-based adhesives, polyvinyl alcohol-based adhesives, polyvinyl porolidone-based adhesives, polyacrylamide-based adhesives, cellulose-based adhesives, and the like can be mentioned. Among these, acrylic pressure-sensitive adhesives are preferred.
• the acrylic pressure-sensitive adhesive contains an acrylic polymer as a base polymer, and examples thereof include the acrylic pressure-sensitive adhesives described in JP-A-2017-75998.
• the acrylic polymer in the acrylic pressure-sensitive adhesive has a monomer unit of (meth)acrylic acid alkyl ester as a main skeleton.
• a (meth)acrylic acid alkyl ester having an alkyl group having 1 to 20 carbon atoms is preferably used, and the content of the (meth)acrylic acid alkyl ester is It is preferably 40% by weight or more, more preferably 60% by weight or more, relative to the total amount of the constituent monomer components.
• a monomer unit such as a nitrogen-containing monomer unit or a hydroxyl group-containing monomer may be included.
• a cross-linking agent may be used to form a cross-linked structure in the pressure-sensitive adhesive layer.
• Commonly used cross-linking agents such as cross-linking agents and metal chelate-based cross-linking agents can be used.
• the amount of the cross-linking agent used is generally 10 parts by weight or less, preferably 5 parts by weight or less, per 100 parts by weight of the base polymer.
• Silane coupling agents terpene-based tackifiers, styrene-based tackifiers, phenol-based tackifiers, rosin-based tackifiers, epoxy-based tackifiers, etc.
• a tackifier may be added.
• an ultraviolet absorber may be added.
• adhesives may contain additives such as plasticizers, softeners, antidegradants, fillers, colorants, antioxidants, surfactants, and antistatic agents. can be used as long as it does not impair the
• the adhesive is applied to a separator that has been subjected to a release treatment, dried to form an adhesive layer, and then transferred to a polarizing film or the like, or the adhesive is polarized.
• a method of applying to a film or the like and drying to form an adhesive layer can be exemplified.
• the thickness of the adhesive layer is not particularly limited, and is, for example, about 1 to 100 ⁇ m, preferably about 2 to 50 ⁇ m.
• the image display device of the present invention includes the pressure-sensitive adhesive layer-attached circularly polarizing film laminate.
• the image display device include a liquid crystal display device and an electroluminescence (EL) display device (eg, an organic EL display device and an inorganic EL display device).
• the pressure-sensitive adhesive layer-attached circularly polarizing film laminate is laminated such that the retardation film side faces the image display cell (for example, liquid crystal cell, organic EL cell, inorganic EL cell) side.
• a front transparent member is disposed on the viewing side of the adhesive layer-attached circularly polarizing film laminate. Examples of the front transparent member include a front transparent plate (window layer) and a touch panel.
• a transparent plate having appropriate mechanical strength and thickness is used as the front transparent plate.
• a transparent plate for example, a transparent resin plate such as acrylic resin or polycarbonate resin, or a glass plate is used.
• the touch panel for example, various types of touch panels such as resistive type, capacitive type, optical type, ultrasonic type, etc., and glass plates and transparent resin plates having a touch sensor function are used.
• a capacitive touch panel is used as the front transparent member, it is preferable that a front transparent plate made of glass or a transparent resin plate is provided on the viewing side of the touch panel.
• the image display device may have a curved shape, or may be bent or bent for use.
• Example 1> ⁇ Preparation of polarizing film> A polyvinyl alcohol film having an average degree of polymerization of 2,400, a degree of saponification of 99.9 mol % and a thickness of 45 ⁇ m was prepared. A polyvinyl alcohol film is immersed in a swelling bath (water bath) at 30° C. for 30 seconds between rolls having different peripheral speed ratios, and stretched by 2.2 times in the conveying direction while swelling (swelling step).
• a swelling bath water bath
• the polarizing film was adjusted to a predetermined transmittance. It was immersed for 30 seconds while adjusting the iodine concentration and stretched 3.3 times in the transport direction based on the original polyvinyl alcohol film (polyvinyl alcohol film not stretched at all in the transport direction) while dyeing (dyeing process). . Then, the dyed polyvinyl alcohol film is placed in a 40° C.
• crosslinking bath an aqueous solution with a boric acid concentration of 3.5% by weight, a potassium iodide concentration of 3.0% by weight, and a zinc sulfate concentration of 3.6% by weight.
• crosslinking step for 28 seconds and stretched up to 3.6 times in the conveying direction with respect to the original polyvinyl alcohol film (crosslinking step).
• the obtained polyvinyl alcohol film was placed in a drawing bath (an aqueous solution having a boric acid concentration of 4.5% by weight, a potassium iodide concentration of 5.0% by weight, and a zinc sulfate concentration of 5.0% by weight) at 64°C.
• the fluorescent X-ray intensity (kcps) of potassium element was measured using a fluorescent X-ray analyzer (manufactured by Rigaku, trade name “ZSX100E”, measurement diameter: ⁇ 10 mm).
• the thickness ( ⁇ m) of the polarizing film was measured using a spectroscopic film thickness meter (manufactured by PEACOCK, trade name “DG-205”).
• the potassium content (% by weight) was determined from the obtained fluorescent X-ray intensity and thickness using the following formula.
• ⁇ Method for measuring content (% by weight) of water-soluble radical scavenger in polarizing film About 20 mg of the polarizing film was collected, quantified, dissolved by heating in 1 mL of water, diluted with 4.5 mL of methanol, the resulting extract was filtered through a membrane filter, and the filtrate was subjected to HPLC (Waters ACQUITY UPLC H-class Bio) was used to measure the concentration of the water-soluble radical scavenger.
• ⁇ Preparation of polarizing film> polyvinyl alcohol resin containing an acetoacetyl group (average degree of polymerization: 1,200, degree of saponification: 98.5 mol%, degree of acetoacetylation: 5 mol%) and methylol melamine at a weight ratio of 3: The aqueous solution contained in 1 was used. Using this adhesive, HC was applied to a triacetyl cellulose film (manufactured by Fujifilm, trade name "TJ40UL") as a first transparent protective film on one side (viewing side) of the polarizing film obtained above.
• TJ40UL triacetyl cellulose film
• a transparent protective film having a thickness of 48 ⁇ m (water vapor permeability of 300 g/(m 2 ⁇ 24 h)) was formed, and a second transparent protective film having a thickness of 40 ⁇ m was formed on the other surface (the image display cell side).
• System transparent protective film manufactured by Konica Minolta, KC4CT, moisture permeability of 800 g / (m 2 ⁇ 24 h)
• a roll laminator is laminated with a roll laminator, and then heated and dried in an oven (temperature is 90 ° C., time is 10 minutes) to prepare a polarizing film in which transparent protective films were laminated on both sides of the polarizing film.
• the direction of the orientation treatment was set at 15° to the direction of the absorption axis of the polarizing film when viewed from the viewing side when the film was attached to the polarizing film.
• the above liquid crystal coating solution was applied to the alignment-treated surface using a bar coater, and dried by heating at 90° C. for 2 minutes to align the liquid crystal compound.
• a metal halide lamp was used to irradiate the liquid crystal layer thus formed with light of 1 mJ/cm 2 to cure the liquid crystal layer, thereby forming a liquid crystal alignment fixed layer A on the PET film.
• the liquid crystal alignment fixed layer A had a thickness of 2.5 ⁇ m and an in-plane retardation Re (550) of 270 nm.
• the coating thickness was changed and the orientation treatment direction was set to be 75° to the direction of the absorption axis of the polarizing film when viewed from the viewing side.
• a liquid crystal alignment fixed layer B was formed.
• the liquid crystal alignment fixed layer B had a thickness of 1.5 ⁇ m and an in-plane retardation Re (550) of 140 nm.
• an acrylic polymer solution having a weight average molecular weight (Mw) of 1,800,000.
• Mw weight average molecular weight
• 0.02 parts of an isocyanate cross-linking agent manufactured by Tosoh Corporation, trade name "Takenate D110N", trimethylolpropane/xylylene diisocyanate adduct
• silane 0.2 parts of a coupling agent manufactured by Shin-Etsu Chemical Co., Ltd., trade name “X-41-1056” was added to prepare a solution of an acrylic pressure-sensitive adhesive composition.
• Example 2 In the preparation of the polarizing film, the compound represented by the general formula (2) was not added to the washing bath, and the boron content in the obtained polarizing film was 4.6% by weight, and the potassium content was A pseudo image display panel was produced in the same manner as in Example 1, except that the concentration of the drawing bath was adjusted to 0.5% by weight.
• Example 3 In the preparation of the polarizing film, the resulting polarizing film has a boron content of 4.6% by weight, a potassium content of 0.5% by weight, and is stretched so that the single transmittance of the polarizing film is 42.0%.
• a pseudo image display panel was produced using a pressure-sensitive adhesive layer-attached circularly polarizing film laminate having a single transmittance of 42.4% in the same manner as in Example 2, except that the concentration of the bath was adjusted. Single transmittance of circularly polarizing film laminate with adhesive layer is 42.4%
• Example 4 In the preparation of the polarizing film, the resulting polarizing film has a boron content of 4.6% by weight, a potassium content of 0.5% by weight, and is stretched so that the single transmittance of the polarizing film is 40.7%.
• a pseudo image display panel was produced using a pressure-sensitive adhesive layer-attached circularly polarizing film laminate having a single transmittance of 41.2% in the same manner as in Example 1, except that the concentration of the bath was adjusted.
• Example 1 In the preparation of the polarizing film, the single transmission was performed in the same manner as in Example 2, except that the concentration of the iodine aqueous solution in the dyeing bath was adjusted so that the single transmission of the resulting polarizing film was 42.6%.
• a pseudo image display panel was produced using a circularly polarizing film laminate with an adhesive layer having a ratio of 43.0%.
• the temperature rise and pressure reduction in the second reactor were started, and the internal temperature was brought to 240° C. and the pressure to 0.2 kPa in 50 minutes. After that, polymerization was allowed to proceed until a predetermined stirring power was obtained. When a predetermined power was reached, nitrogen was introduced into the reactor to restore the pressure, the polyester carbonate-based resin produced was extruded into water, and strands were cut to obtain pellets. After vacuum drying the obtained polyester carbonate resin (pellet) at 80 ° C.
• a single screw extruder (Toshiba Machine Co., Ltd., cylinder setting temperature: 250 ° C.), T die (width 200 mm, setting temperature: 250 ° C.), a chill roll (set temperature: 120 to 130° C.) and a film forming apparatus equipped with a winder to prepare a long resin film having a thickness of 130 ⁇ m.
• the obtained long resin film was stretched while being adjusted so as to obtain a predetermined retardation to obtain a PEC film (retardation film) having a thickness of 48 ⁇ m.
• the stretching conditions were a stretching temperature of 143° C. and a stretching ratio of 2.8 in the width direction.
• Re(550) of the obtained retardation film was 141 nm.
• the pseudo image display panel obtained above was placed in a hot air oven at a temperature of 105° C. for 1000 hours, and the difference in transmittance ( ⁇ Ts) and the difference in reflectance ( ⁇ reflectance) before and after introduction (heating) were measured. It was measured.
• Single transmittance was measured using a spectrophotometer (LPF-200, manufactured by Otsuka Electronics Co., Ltd.).
• the single transmittance is a Y value corrected for visual sensitivity using a 2-degree field of view (C light source) of Jls Z 8701-1982.
• the measurement wavelength is 380 to 780 nm (every 5 nm).
• Reflectance is measured by placing a pseudo image display panel on a reflector (manufactured by Toray Film Co., Ltd., trade name "DMS-X42"; reflectance 86%) and using a spectrophotometer (manufactured by Konica Minolta, CM-2600d). It was measured by the SCI method.
• ⁇ Ts The determination ( ⁇ Ts) in the durability test is as follows. ⁇ : ⁇ Ts (%) is 0% or more and less than 1%. ⁇ : ⁇ Ts (%) is 1% or more and less than 3%. x: ⁇ Ts (%) is 3% or more.
• the determination ( ⁇ reflectance) in the durability test is as follows. ⁇ : ⁇ reflectance (%) is 0% or more and less than 0.5%. x: ⁇ reflectance (%) is 0.5 or more.

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