WO2015098734A1 - 偏光子、ならびに、この偏光子を備える偏光板および偏光性積層フィルム - Google Patents
偏光子、ならびに、この偏光子を備える偏光板および偏光性積層フィルム Download PDFInfo
- Publication number
- WO2015098734A1 WO2015098734A1 PCT/JP2014/083672 JP2014083672W WO2015098734A1 WO 2015098734 A1 WO2015098734 A1 WO 2015098734A1 JP 2014083672 W JP2014083672 W JP 2014083672W WO 2015098734 A1 WO2015098734 A1 WO 2015098734A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- film
- polarizer
- resin
- stretching
- polarizing plate
- Prior art date
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
-
- 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
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- 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
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
- B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
-
- 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
- B32B7/04—Interconnection of layers
- B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
- G02B5/3041—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks
- G02B5/305—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks including organic materials, e.g. polymeric layers
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3075—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state for use in the UV
-
- 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
- B32B2307/00—Properties of the layers or laminate
- B32B2307/40—Properties of the layers or laminate having particular optical properties
- B32B2307/42—Polarizing, birefringent, filtering
-
- 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
- B32B2457/00—Electrical equipment
- B32B2457/20—Displays, e.g. liquid crystal displays, plasma displays
- B32B2457/202—LCD, i.e. liquid crystal displays
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
- G02B1/14—Protective coatings, e.g. hard coatings
Definitions
- the present invention relates to a polarizer, and a polarizing plate and a polarizing laminate film provided with the polarizer.
- the polarizing plate has been widely used in display devices such as liquid crystal display devices, particularly in recent years for various mobile devices such as smartphones and slate PCs.
- a polarizing plate has a configuration in which a protective film is bonded to one or both sides of a polarizer using an adhesive.
- Patent Documents 1 to 8 JP 2013-228726 A, JP 2013-210513 A, JP 2012-144690 A, JP 2009-109994 A, JP 2009-139585 A, JP 2010- No. 091603, JP 2010-091602 A, and JP 2008-170717 A describe a polarizing plate in which a protective film is bonded to a polarizer using a photocurable adhesive.
- a protective film of a polarizer instead of a material having a relatively high moisture permeability that can be bonded with a water-based adhesive such as a cellulose resin, a cycloolefin resin or an olefin resin having a lower moisture permeability.
- a water-based adhesive such as a cellulose resin, a cycloolefin resin or an olefin resin having a lower moisture permeability.
- Materials such as resin, acrylic resin, and polyethylene terephthalate resin have been used.
- such a material with low moisture permeability cannot be sufficiently adhered to the polarizer even when an aqueous adhesive is used, and is often adhered to the polarizer using a photocurable adhesive or the like.
- the cured layer of the adhesive may be altered by light, so that, for example, a protective film contains an ultraviolet absorber so as to ensure light resistance when used as a display device. It is desirable to make it. Further, for example, a coating type retardation film may be formed on the surface of the protective film. In these cases, the ultraviolet transmittance on the protective film side is remarkably lowered, and there is a problem that the adhesive cannot be sufficiently cured by light irradiation from the protective film side.
- a method using a photopolymerization initiator or a photosensitizer having an absorption band in a wavelength range of about 370 to 420 nm which is more visible as a component of a photocurable adhesive is known. Cited as a technology.
- the range of the absorption wavelength of the photopolymerization initiator or photosensitizer extends to the visible range, so that the polarizing plate itself is colored, and the polarizing plate has a neutral (uncolored) hue. There is a risk of inconvenience that it cannot be maintained.
- an object of the present invention is to provide a polarizer in which a photocurable adhesive is sufficiently cured by light irradiation and can maintain a neutral hue, and a polarizing plate including the polarizer and The object is to provide a polarizing laminate film.
- a polarizing plate comprising the polarizer according to [1] above and a protective film laminated on the polarizer via an adhesive layer made of a cured product of a light-transmitting adhesive.
- the protective film has a light transmittance at a wavelength of 365 nm of less than 5%.
- the photocurable adhesive contains a photopolymerization initiator having a maximum absorption wavelength between 280 and 320 nm.
- a photocurable adhesive is sufficiently cured by light irradiation, and a polarizer capable of maintaining a neutral hue, and a polarizing plate and a polarizing laminate film including the polarizer are provided. can do.
- FIG. 1 is a schematic cross-sectional view showing an example of a layer configuration of a polarizing plate according to the present invention.
- the polarizing plate of this invention is a polarizing plate with a single-sided protective film provided with the polarizer 5 and the protective film 10 laminated
- FIG. 2 is a schematic sectional view showing a state when the polarizing plate shown in FIG. 1 is arranged on the display cell.
- the protective film 10 is a protective film disposed outside when the polarizing plate 1 is disposed on the display cell 4, and when the polarizing plate 1 is disposed on the display cell 4. Moreover, it is a protective film that typically forms the outermost surface.
- the polarizing plate 1 can be disposed and bonded onto the display cell 4 using an adhesive layer 2 provided on the outer surface of the polarizer 5.
- the maximum absorbance of the polarizer at a wavelength of 280 to 320 nm is 0.70 or less, more preferably 0.68 or less.
- the absorbance is a value that can be measured with an absorptiometer or the like.
- the intensity of transmitted light when natural light (light having a wavelength of 280 to 320 nm) is incident on a sample (polarizer) as incident light is measured. It is obtained by the formula.
- T 0 the incident light intensity
- T the transmitted light intensity
- the measurement result of the absorbance of the polarizer varies depending on the polarization state of the incident light. For example, depending on the absorptiometer, some polarization may occur due to the influence of mirrors and optical elements between the light source and the sample (polarizer), or a polarization separation element such as a prism may be included. Caution must be taken. In the case of such a measuring machine, after measuring the polarizer at a certain angle, measure the same polarizer again in the direction rotated 90 degrees, and calculate the absorbance from the average value of these transmitted light intensities, The influence of the polarization direction of incident light can be eliminated.
- UV-B ultraviolet rays
- the polarizing plate can be stably used regardless of the type of the protective film. Can be manufactured. This effect is particularly effective when producing a polarizer of 10 ⁇ m or less. That is, in order to create a polarizer of 10 ⁇ m or less, a coating liquid is applied on a base film to form a polyvinyl alcohol-based resin layer, and the base is stretched together with the polarizer (the base film and the base film).
- a method for producing a polarizing laminated film comprising a polarizer provided on both sides of a base film, but at this time, polyvinyl alcohol resin layers are provided on both sides of the base film in order to prevent curling.
- the effect of the present invention is particularly useful because it is necessary to irradiate the photocurable adhesive with ultraviolet rays through two polarizers.
- the thickness of the polarizer 5 is preferably 10 ⁇ m or less, more preferably 7 ⁇ m or less. Setting the thickness of the polarizer 5 to 10 ⁇ m or less is advantageous for reducing the thickness of the polarizing plate.
- the polarizer 5 can be obtained by adsorbing and orienting a dichroic dye on a uniaxially stretched polyvinyl alcohol resin layer.
- a saponified polyvinyl acetate resin can be used as the polyvinyl alcohol resin constituting the polyvinyl alcohol resin layer.
- the polyvinyl acetate-based resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith.
- Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.
- a film formed of such a polyvinyl alcohol resin constitutes the polarizer 5.
- the method for forming the polyvinyl alcohol-based resin is not particularly limited, and can be formed by a known method. However, from the viewpoint that it is easy to obtain the polarizer 5 having a thickness of 10 ⁇ m or less, It is preferable to form a film by applying the solution on a base film.
- the polarizer 5 needs to be stretched and oriented, and is preferably stretched at a stretch ratio of more than 5 times, more preferably more than 5 times and not more than 17 times.
- the degree of saponification of the polyvinyl alcohol-based resin can be in the range of 80.0 to 100.0 mol%, preferably in the range of 90.0 to 99.5 mol%, more preferably 94.0. It is in the range of ⁇ 99.0 mol%.
- the degree of saponification is less than 80.0 mol%, the water resistance and heat-and-moisture resistance of the obtained polarizing plates 1 and 2 are lowered.
- a polyvinyl alcohol-based resin having a saponification degree exceeding 99.5 mol% is used, the dyeing speed becomes slow, the productivity decreases, and the polarizer 5 having sufficient polarization performance may not be obtained.
- the degree of saponification is the unit ratio (mol%) of the ratio of acetate groups (acetoxy groups: —OCOCH 3 ) contained in polyvinyl acetate resin, which is a raw material for polyvinyl alcohol resins, to hydroxyl groups by the saponification process.
- the following formula: Saponification degree (mol%) 100 ⁇ (number of hydroxyl groups) ⁇ (number of hydroxyl groups + number of acetate groups) Defined by The saponification degree can be determined according to JIS K 6726 (1994). The higher the degree of saponification, the higher the proportion of hydroxyl groups, and thus the lower the proportion of acetate groups that inhibit crystallization.
- the polyvinyl alcohol resin may be a modified polyvinyl alcohol partially modified.
- polyvinyl alcohol resins modified with olefins such as ethylene and propylene; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; alkyl esters of unsaturated carboxylic acids, acrylamide, and the like can be used.
- the proportion of modification is preferably less than 30 mol%, and more preferably less than 10%. When modification exceeding 30 mol% is performed, it becomes difficult to adsorb the dichroic dye, and the polarizer 5 having sufficient polarization performance cannot be obtained.
- the average degree of polymerization of the polyvinyl alcohol-based resin is preferably 100 to 10,000, more preferably 1500 to 8000, and further preferably 2000 to 5000.
- the average degree of polymerization of the polyvinyl alcohol resin can also be determined according to JIS K 6726 (1994).
- polyvinyl alcohol resins suitably used in the present invention are trade names, “PVA124” (degree of saponification: 98.0 to 99.0 mol%) manufactured by Kuraray Co., Ltd., “ PVA117 "(degree of saponification: 98.0 to 99.0 mol%),” PVA624 “(degree of saponification: 95.0 to 96.0 mol%),” PVA617 “(degree of saponification: 94.5 to 95) 5 mol%); “AH-26” (degree of saponification: 97.0 to 98.8 mol%) and “AH-22” (degree of saponification: 97.5 to 9) manufactured by Nippon Synthetic Chemical Industry Co., Ltd.
- the dichroic dye contained (adsorption orientation) in the polarizer 5 can be iodine or a dichroic organic dye.
- the dichroic organic dye include: Red BR, Red LR, Red R, Pink LB, Rubin BL, Bordeaux GS, Sky Blue LG, Lemon Yellow, Blue BR, Blue 2R, Navy RY, Green LG, Violet LB, Violet B, Black H, Black B, Black GSP, Yellow 3G, Yellow R, Orange LR, Orange 3R, Scarlet GL, Scarlet KGL, Congo Red, Brilliant Violet BK, Spura Blue G, Spura Blue GL, Spura Orange GL, Direct Includes Sky Blue, Direct First Orange S and First Black.
- a dichroic dye may be used individually by 1 type, and may use 2 or more types together.
- Each of the protective films 10 is a thermoplastic resin, for example, a polyolefin resin such as a chain polyolefin resin (polypropylene resin, etc.) or a cyclic polyolefin resin (norbornene resin, etc.); cellulose triacetate, cellulose Cellulose ester resin such as diacetate; Polyester resin such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate; Polycarbonate resin; (Meth) acrylic resin; or a mixture or copolymer thereof It can be a resin film.
- a polyolefin resin such as a chain polyolefin resin (polypropylene resin, etc.) or a cyclic polyolefin resin (norbornene resin, etc.
- cellulose triacetate cellulose Cellulose ester resin such as diacetate
- Polyester resin such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate
- the cyclic polyolefin resin is a general term for resins that are polymerized using a cyclic olefin as a polymerization unit, and is described in, for example, JP-A-1-240517, JP-A-3-14882, JP-A-3-122137, and the like. Resin.
- cyclic polyolefin resins include ring-opening (co) polymers of cyclic olefins, addition polymers of cyclic olefins, copolymers of cyclic olefins and chain olefins such as ethylene and propylene (typically Are random copolymers), graft polymers obtained by modifying them with unsaturated carboxylic acids or derivatives thereof, and hydrides thereof.
- norbornene resins using norbornene monomers such as norbornene and polycyclic norbornene monomers as cyclic olefins are preferably used.
- cyclic polyolefin resins Various products are commercially available for cyclic polyolefin resins.
- Examples of commercial products of cyclic polyolefin resins are trade names, “Topas” (Topas Advanced Polymers GmbH, available from Polyplastics Co., Ltd.), “Arton” (manufactured by JSR Corporation), Includes “ZEONOR” (manufactured by Nippon Zeon Co., Ltd.), “ZEONEX” (manufactured by Nippon Zeon Co., Ltd.), and “Apel” (manufactured by Mitsui Chemicals, Inc.).
- the cellulose ester resin is an ester of cellulose and a fatty acid.
- Specific examples of the cellulose ester resin include cellulose triacetate, cellulose diacetate, cellulose tripropionate, and cellulose dipropionate.
- these copolymers and those in which a part of the hydroxyl group is modified with other substituents can also be used.
- cellulose triacetate triacetyl cellulose: TAC
- TAC triacetyl cellulose
- Many products of cellulose triacetate are commercially available, which is advantageous in terms of availability and cost.
- Examples of commercial products of cellulose triacetate are trade names of “Fujitac TD80” (manufactured by Fuji Film Co., Ltd.), “Fujitac TD80UF” (manufactured by Fuji Film Co., Ltd.), and “Fujitac TD80UZ” (Fuji Film Co., Ltd.). )), “Fujitac TD40UZ” (manufactured by Fujifilm), “KC8UX2M” (manufactured by Konica Minolta Opto), and “KC4UY” (manufactured by Konica Minolta Opto).
- the protective film 10 can also be a protective film having an optical function such as a retardation film and a brightness enhancement film.
- a retardation film provided with an arbitrary retardation value by stretching a transparent resin film made of the above material (uniaxial stretching or biaxial stretching) or forming a liquid crystal layer or the like on the film. It can be.
- the light transmittance of the protective film 10 at a wavelength of 365 nm is preferably less than 5%.
- the transmittance of the protective film for ultraviolet rays having a shorter wavelength (light rays having a wavelength of 280 to 320 nm: UV-B, etc.) is also low.
- the adhesive is cured by irradiating ultraviolet rays (UV-B, etc.) with the protective film laminated on the polarizer via the photocurable adhesive, the ultraviolet rays are irradiated from the protective film side.
- the photocurable adhesive cannot be cured.
- the thickness of the protective film 10 is preferably 80 ⁇ m or less, more preferably 60 ⁇ m or less, and even more preferably 50 ⁇ m or less, from the viewpoint of thinning the polarizing plate. Moreover, the thickness of the protective film 10 is normally 5 micrometers or more from a viewpoint of ensuring film strength.
- a surface treatment layer such as a hard coat layer, an antiglare layer, an antireflection layer, an antistatic layer, or an antifouling layer may be formed on the surface of the protective film 10 opposite to the polarizer 5. It can.
- the method for forming the surface treatment layer on the surface of the protective film is not particularly limited, and a known method can be used.
- the adhesive layer 15 is a layer made of a cured product of a photocurable adhesive.
- a photocurable adhesive refers to an adhesive that cures by irradiating an active energy ray such as ultraviolet rays.
- the thing containing resin and a photoreactive crosslinking agent can be mentioned.
- a photocurable adhesive can eliminate the need for a drying step, and 2) used for bonding a protective film with low moisture permeability. There is an advantage that there are many types of protective films that can be bonded compared to aqueous adhesives.
- Examples of the polymerizable compound include a photocurable epoxy compound; a photocurable vinyl compound such as a photocurable acrylic compound; and a photocurable urethane compound.
- photopolymerization initiator examples include a cationic photopolymerization initiator (for example, when using a photocurable epoxy compound) and a photoradical polymerization initiator (for example, when using a photocurable acrylic compound). .
- the maximum absorption wavelength of the photopolymerization initiator contained in the photopolymerizable adhesive used for bonding the protective film and the polarizer is preferably between 280 and 320 nm.
- a polarizing plate can be provided.
- the polarizing plate 1 is placed on another member (for example, the display cell 4 of the display device) on the outer surface of the polarizer 5 (the surface opposite to the adhesive layer 15). You may laminate
- the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 2 is usually based on a (meth) acrylic resin, styrene resin, or silicone resin as a base polymer, and a crosslinking agent such as an isocyanate compound, epoxy compound, or aziridine compound is added thereto. It consists of an adhesive composition. Furthermore, it can also be set as the adhesive layer which contains microparticles
- the thickness of the pressure-sensitive adhesive layer 2 can be 1 to 40 ⁇ m, but it is preferably formed thin as long as it does not impair the workability and durability characteristics, and specifically 3 to 25 ⁇ m. A thickness of 3 to 25 ⁇ m has good processability and is suitable for suppressing the dimensional change of the polarizer 5.
- the pressure-sensitive adhesive layer 2 is less than 1 ⁇ m, the adhesiveness is lowered, and when it exceeds 40 ⁇ m, problems such as the pressure-sensitive adhesive protruding easily occur.
- the method of forming the pressure-sensitive adhesive layer 2 is not particularly limited, and a pressure-sensitive adhesive composition (pressure-sensitive adhesive solution) containing each component including the above-described base polymer is applied to the surface of the polarizer 5,
- the pressure-sensitive adhesive layer 2 may be formed by drying, or the pressure-sensitive adhesive layer 2 may be transferred to the polarizer 5 after forming the pressure-sensitive adhesive layer 2 in the same manner on the separator (release film).
- a surface treatment such as a corona treatment may be applied to the surface of the polarizer 5 or the surface of the pressure-sensitive adhesive layer 2 as necessary.
- the polarizing plate 1 can further include another optical layer laminated on the protective film 10 or the polarizer 5.
- a reflective polarizing film that transmits a certain kind of polarized light and reflects polarized light that exhibits the opposite properties
- a film with an antiglare function having a concavo-convex shape on the surface
- a film with a surface antireflection function A reflective film having a reflective function on the surface
- a transflective film having both a reflective function and a transmissive function
- a viewing angle compensation film a reflective polarizing film that transmits a certain kind of polarized light and reflects polarized light that exhibits the opposite properties
- a film with an antiglare function having a concavo-convex shape on the surface
- a film with a surface antireflection function A reflective film having a reflective function on the surface
- a transflective film having both a reflective function and a transmissive function
- a viewing angle compensation film a viewing angle compensation
- DBEF (manufactured by 3M, Sumitomo 3M Co., Ltd. in Japan) can be used as a commercial product corresponding to a reflective polarizing film that transmits certain types of polarized light and reflects polarized light that exhibits the opposite properties.
- APF (manufactured by 3M, available from Sumitomo 3M Limited in Japan).
- the viewing angle compensation film examples include an optical compensation film in which a liquid crystal compound is applied to the substrate surface, and is oriented / fixed, a retardation film made of a polycarbonate resin, a retardation film made of a cyclic polyolefin resin, and the like. .
- WV film manufactured by Fujifilm Corporation
- NH film JX Nippon Mining & Metals. Energy Co., Ltd.
- NR Film manufactured by JX Nippon Oil & Energy Corporation
- the polarizing plate of the present invention can be preferably produced by, for example, the method shown in FIG.
- the manufacturing method of the polarizing plate shown by FIG. 3 is a method for manufacturing the polarizing plate 1 with a protective film, and the following process: (1) Resin layer forming step S10 in which a coating liquid containing a polyvinyl alcohol-based resin is applied to at least one surface of a base film and then dried to form a polyvinyl alcohol-based resin layer to obtain a laminated film.
- Stretching step S20 to stretch the laminated film to obtain a stretched film
- Dyeing step S30 to obtain a polarizing laminated film by dyeing the polyvinyl alcohol resin layer of the stretched film with a dichroic dye to form a polarizer
- Bonding process S40 which bonds the any one of a protective film through the adhesive bond layer on the polarizer of a light-polarizing laminated film, and obtains a bonding film
- Peeling step S50 to obtain a polarizing plate with a single-sided protective film by peeling and removing the base film from the bonding film.
- this step is a step of obtaining laminated film 100 by forming polyvinyl alcohol resin layers 61 and 62 on both surfaces of base film 30.
- the polyvinyl alcohol-based resin layers 61 and 62 are layers that become the polarizers 51 and 52 through the stretching step S20 and the dyeing step S30.
- the polyvinyl alcohol resin layers 61 and 62 can be formed by applying a coating liquid containing a polyvinyl alcohol resin on both surfaces of the base film 30 and drying the coating layer. The method of forming the polyvinyl alcohol-based resin layer by such coating is advantageous in that the thin film polarizers 51 and 52 can be easily obtained.
- the base film 30 can be composed of a thermoplastic resin, and among them, it is preferably composed of a thermoplastic resin that is excellent in transparency, mechanical strength, thermal stability, stretchability, and the like.
- thermoplastic resins include, for example, polyolefin resins such as chain polyolefin resins and cyclic polyolefin resins (norbornene resins, etc.); polyester resins; (meth) acrylic resins; cellulose triacetate, Cellulose ester resins such as cellulose diacetate; Polycarbonate resins; Polyvinyl alcohol resins; Polyvinyl acetate resins; Polyarylate resins; Polystyrene resins; Polyethersulfone resins; Polysulfone resins; Polyamide resins; System resins; and mixtures and copolymers thereof.
- the base film 30 may have a single-layer structure made of one resin layer made of one kind or two or more kinds of thermoplastic resins, or a plurality of resin layers made of one kind or two or more kinds of thermoplastic resins.
- a laminated multilayer structure may be used.
- the base film 30 may be composed of a resin that can be stretched at a stretching temperature suitable for stretching the polyvinyl alcohol-based resin layers 61 and 62 when the laminated film 100 is stretched in the stretching step S20 described later. preferable.
- the chain polyolefin resin examples include a homopolymer of a chain olefin such as a polyethylene resin and a polypropylene resin, and a copolymer composed of two or more chain olefins.
- the base film 30 made of a chain polyolefin-based resin is preferable in that it is easily stretched stably at a high magnification.
- the base film 30 is composed mainly of a polypropylene resin (a polypropylene resin that is a propylene homopolymer or a copolymer mainly composed of propylene), a polyethylene resin (a polyethylene resin that is an ethylene homopolymer or ethylene). It is more preferable that it consists of a copolymer.
- the copolymer mainly composed of propylene which is one of the examples suitably used as the thermoplastic resin constituting the base film 30, is a copolymer of propylene and another monomer copolymerizable therewith.
- Examples of other monomers copolymerizable with propylene include ethylene and ⁇ -olefin.
- ⁇ -olefin an ⁇ -olefin having 4 or more carbon atoms is preferably used, and more preferably an ⁇ -olefin having 4 to 10 carbon atoms.
- Specific examples of the ⁇ -olefin having 4 to 10 carbon atoms include linear monoolefins such as 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene and 1-decene; Branched monoolefins such as methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene; including vinylcyclohexane.
- the copolymer of propylene and other monomers copolymerizable therewith may be a random copolymer or a block copolymer.
- the content of the other monomer in the copolymer is, for example, 0.1 to 20% by weight, preferably 0.5 to 10% by weight.
- the content of other monomers in the copolymer can be determined by measuring infrared (IR) spectrum according to the method described on page 616 of "Polymer Analysis Handbook" (1995, published by Kinokuniya Shoten). Can be sought.
- polypropylene resin a propylene homopolymer, a propylene-ethylene random copolymer, a propylene-1-butene random copolymer, or a propylene-ethylene-1-butene random copolymer is preferably used.
- the stereoregularity of the polypropylene resin is substantially isotactic or syndiotactic.
- the base film 30 made of a polypropylene-based resin having substantially isotactic or syndiotactic stereoregularity has relatively good handleability and excellent mechanical strength in a high temperature environment.
- the polyester-based resin is a resin having an ester bond, and is generally made of a polycondensate of a polyvalent carboxylic acid or a derivative thereof and a polyhydric alcohol.
- a polyvalent carboxylic acid or a derivative thereof a divalent dicarboxylic acid or a derivative thereof can be used, and examples thereof include terephthalic acid, isophthalic acid, dimethyl terephthalate, and dimethyl naphthalenedicarboxylate.
- a divalent diol can be used, and examples thereof include ethylene glycol, propanediol, butanediol, neopentyl glycol, and cyclohexanedimethanol.
- polyester resin is polyethylene terephthalate, which is a polycondensate of terephthalic acid and ethylene glycol.
- Polyethylene terephthalate is a crystalline resin, but the one in a state before crystallization treatment is more easily subjected to treatment such as stretching. If necessary, it can be crystallized during stretching or by heat treatment after stretching.
- a copolymerized polyester having a crystallinity lowered (or made amorphous) by further copolymerizing another monomer with a polyethylene terephthalate skeleton is also preferably used.
- examples of such resins include those obtained by copolymerizing cyclohexanedimethanol and isophthalic acid. Since these resins are also excellent in stretchability, they can be suitably used.
- polyester resins other than polyethylene terephthalate and copolymers thereof include, for example, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polycyclohexanedimethyl terephthalate. , Polycyclohexanedimethyl naphthalate, and mixtures and copolymers thereof.
- the (meth) acrylic resin is a resin containing a compound having a (meth) acryloyl group as a main constituent monomer.
- Specific examples of the (meth) acrylic resin include, for example, poly (meth) acrylic acid esters such as polymethyl methacrylate; methyl methacrylate- (meth) acrylic acid copolymer; methyl methacrylate- (meth) acrylic acid Ester copolymer; methyl methacrylate-acrylate ester- (meth) acrylic acid copolymer; (meth) methyl acrylate-styrene copolymer (MS resin, etc.); methyl methacrylate and alicyclic hydrocarbon group And a copolymer with the compound (for example, methyl methacrylate-cyclohexyl methacrylate copolymer, methyl methacrylate- (meth) acrylate norbornyl copolymer, etc.).
- a polymer based on a poly (meth) acrylic acid C 1-6 alkyl ester such as poly (meth) acrylic acid methyl is used, and more preferably methyl methacrylate is used as a main component (50 to 100). % Methyl methacrylate-based resin is used.
- Polycarbonate resin is an engineering plastic made of a polymer in which monomer units are bonded via a carbonate group, and is a resin having high impact resistance, heat resistance, flame retardancy, and transparency.
- the polycarbonate resin constituting the base film 30 may be a resin called a modified polycarbonate in which the polymer skeleton is modified in order to lower the photoelastic coefficient, a copolymerized polycarbonate with improved wavelength dependency, or the like.
- Polycarbonate resin is available in various products. Examples of commercially available polycarbonate-based resins are all “Panlite” (manufactured by Teijin Chemicals Ltd.), “Iupilon” (manufactured by Mitsubishi Engineering Plastics), “SD Polyca” (Sumitomo Dow). (Manufactured by Dow Chemical Co., Ltd.).
- polypropylene resins are preferably used from the viewpoints of stretchability and heat resistance.
- the matters described for the protective film are cited. Further, the chain polyolefin resin, polyester resin, (meth) acrylic resin, and polycarbonate resin as described above in relation to the base film 30 can also be used as a constituent material of the protective film.
- any suitable additive may be added to the base film 30 in addition to the thermoplastic resin described above.
- suitable additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, mold release agents, anti-coloring agents, flame retardants, nucleating agents, antistatic agents, pigments, and coloring agents.
- the content of the thermoplastic resin in the base film 30 is preferably 50 to 100% by weight, more preferably 50 to 99% by weight, still more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. . When the content of the thermoplastic resin in the base film 30 is less than 50% by weight, the high transparency inherent in the thermoplastic resin may not be sufficiently exhibited.
- the thickness of the base film 30 can be determined as appropriate, but generally it is preferably 1 to 500 ⁇ m, more preferably 1 to 300 ⁇ m, further preferably 5 to 200 ⁇ m, from the viewpoint of workability such as strength and handleability. Most preferred is 150 ⁇ m.
- the coating liquid is preferably a polyvinyl alcohol resin solution obtained by dissolving polyvinyl alcohol resin powder in a good solvent (for example, water).
- a good solvent for example, water
- the coating liquid may contain additives such as a plasticizer and a surfactant as necessary.
- a plasticizer polyol or a condensate thereof can be used, and examples thereof include glycerin, diglycerin, triglycerin, ethylene glycol, propylene glycol, and polyethylene glycol.
- the blending amount of the additive is preferably 20% by weight or less of the polyvinyl alcohol resin.
- the coating liquid is applied to the base film 30 by a wire bar coating method; a roll coating method such as reverse coating or gravure coating; a die coating method; a comma coating method; a lip coating method; a spin coating method;
- the method can be appropriately selected from a method such as a fountain coating method, a dipping method, and a spray method.
- the coating liquid When the coating liquid is applied to both surfaces of the base film 30, it can be performed one side at a time using the above-described method, or the base material can be formed using a dipping method, a spray coating method, or other special equipment. It is also possible to apply to both sides of the film 30 simultaneously.
- the drying temperature and drying time of the coating layer are set according to the type of solvent contained in the coating solution.
- the drying temperature is, for example, 50 to 200 ° C., preferably 60 to 150 ° C.
- the drying temperature is preferably 80 ° C. or higher.
- the drying time is, for example, 2 to 20 minutes.
- two polyvinyl alcohol resin layers 61 and 62 are formed on both surfaces of the base film 30.
- a polyvinyl alcohol-type resin layer is formed on both surfaces of the base film 30.
- curling of the film which may occur at the time of manufacturing the polarizing laminated film 300 can be suppressed, and one polarizing laminated film Since 300 to 2 polarizing plates can be obtained, it is advantageous in terms of production efficiency of the polarizing plate.
- the present invention is not limited to this, and the polyvinyl alcohol-based resin layer may be formed only on one surface of the base film 30.
- the thickness of the polyvinyl alcohol-based resin layers 61 and 62 in the laminated film 100 is preferably 3 to 30 ⁇ m, and more preferably 5 to 20 ⁇ m. If the polyvinyl alcohol-based resin layers 61 and 62 have a thickness within this range, the dichroic dye has good dyeability and excellent polarization performance through a stretching step S20 and a dyeing step S30, which will be described later, and a thickness of 10 ⁇ m or less.
- the polarizers 51 and 52 can be obtained. When the thickness of the polyvinyl alcohol resin layers 61 and 62 exceeds 30 ⁇ m, the thickness of the polarizers 51 and 52 may exceed 10 ⁇ m. Moreover, when the thickness of the polyvinyl alcohol-based resin layers 61 and 62 is less than 3 ⁇ m, the film becomes too thin after stretching and the dyeability tends to deteriorate.
- the surface of the base film 30 Prior to the application of the coating solution, in order to improve the adhesion between the base film 30 and the polyvinyl alcohol resin layers 61 and 62, the surface of the base film 30 is subjected to corona treatment, plasma treatment, and flame (flame). You may perform a process etc.
- polyvinyl chloride Prior to the application of the coating liquid, polyvinyl chloride is applied to the base film 30 via a primer layer or an adhesive layer in order to improve the adhesion between the base film 30 and the polyvinyl alcohol resin layers 61 and 62.
- the alcohol-based resin layers 61 and 62 may be formed.
- the primer layer can be formed by applying a primer layer forming coating solution to the surface of the substrate film 30 and then drying it.
- the primer layer forming coating solution contains a component that exhibits a certain degree of strong adhesion to both the base film 30 and the polyvinyl alcohol resin layers 61 and 62.
- the primer layer-forming coating solution usually contains a resin component that imparts such adhesion and a solvent.
- a thermoplastic resin excellent in transparency, thermal stability, stretchability and the like is preferably used, and examples thereof include (meth) acrylic resins and polyvinyl alcohol resins. Among these, polyvinyl alcohol resins that give good adhesion are preferably used.
- polyvinyl alcohol resin examples include polyvinyl alcohol resins and derivatives thereof.
- Polyvinyl alcohol resin derivatives include polyvinyl formal, polyvinyl acetal, etc., as well as polyvinyl alcohol resins modified with olefins such as ethylene and propylene; unsaturated carboxylic acids such as acrylic acid, methacrylic acid and crotonic acid. Denatured; modified with alkyl ester of unsaturated carboxylic acid; modified with acrylamide.
- solvent a general organic solvent or an aqueous solvent capable of dissolving the resin component.
- solvents include, for example, aromatic hydrocarbons such as benzene, toluene and xylene; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate and isobutyl acetate; Chlorinated hydrocarbons such as trichloroethylene and chloroform; alcohols such as ethanol, 1-propanol, 2-propanol and 1-butanol.
- the primer layer is formed using a primer layer forming coating solution containing an organic solvent
- the base film 30 may be dissolved, so the solvent is selected in consideration of the solubility of the base film 30. It is preferable to do.
- the primer layer is preferably formed from a coating solution containing water as a solvent.
- a crosslinking agent may be added to the primer layer forming coating solution.
- a suitable crosslinking agent is appropriately selected from known ones such as organic and inorganic based on the type of thermoplastic resin to be used. Examples of the crosslinking agent include epoxy-based, isocyanate-based, dialdehyde-based, and metal-based crosslinking agents.
- epoxy-based crosslinking agent either one-component curable type or two-component curable type can be used.
- Isocyanate-based crosslinking agents include tolylene diisocyanate, hydrogenated tolylene diisocyanate, trimethylolpropane-tolylene diisocyanate adduct, triphenylmethane triisocyanate, methylenebis (4-phenylmethane) triisocyanate, isophorone diisocyanate, and ketoximes thereof.
- a block thing or a phenol block thing etc. are mentioned.
- dialdehyde-based cross-linking agent examples include glyoxal, malondialdehyde, succindialdehyde, glutardialdehyde, maleidialdehyde, phthaldialdehyde and the like.
- metal-based crosslinking agent examples include metal salts, metal oxides, metal hydroxides, and organometallic compounds.
- metal salt, metal oxide, and metal hydroxide examples include divalent or higher valent metals such as magnesium, calcium, aluminum, iron, nickel, zirconium, titanium, silicon, boron, zinc, copper, vanadium, chromium, and tin. Examples thereof include salts, oxides and hydroxides of metals having a valence.
- An organometallic compound is a compound having in the molecule at least one structure in which an organic group is bonded directly to a metal atom or an organic group is bonded through an oxygen atom, a nitrogen atom, or the like.
- the organic group means a monovalent or polyvalent group containing at least a carbon element, and can be, for example, an alkyl group, an alkoxy group, an acyl group, or the like.
- the bond does not mean only a covalent bond, but may be a coordinate bond by coordination such as a chelate compound.
- organometallic compound examples include an organotitanium compound, an organozirconium compound, an organoaluminum compound, and an organosilicon compound.
- An organometallic compound may be used individually by 1 type, and may use 2 or more types together.
- organic titanium compounds include titanium orthoesters such as tetranormal butyl titanate, tetraisopropyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate; titanium acetylacetonate, titanium tetraacetylacetonate And titanium chelates such as polytitanium acetylacetonate, titanium octylene glycolate, titanium lactate, titanium triethanolamate, and titanium ethyl acetoacetate; and titanium acylates such as polyhydroxytitanium stearate.
- titanium orthoesters such as tetranormal butyl titanate, tetraisopropyl titanate, butyl titanate dimer, tetra (2-ethylhexyl) titanate, tetramethyl titanate
- titanium acetylacetonate titanium tetraacetylacetonate
- organic zirconium compound examples include zirconium normal propionate, zirconium normal butyrate, zirconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium bisacetylacetonate, zirconium acetylacetonate bisethylacetoacetate and the like.
- Examples of the organic aluminum compound include aluminum acetylacetonate and aluminum organic acid chelate.
- Examples of the organic silicon compound include compounds in which the ligands exemplified above for the organic titanium compound and the organic zirconium compound are bonded to silicon.
- polymeric crosslinking agents such as methylolated melamine resins and polyamide epoxy resins can also be used.
- polyamide epoxy resins include “Smilease Resin 650 (30)” and “Smilease Resin 675” (both trade names) sold by Taoka Chemical Co., Ltd.
- a polyvinyl alcohol-based resin is used as a resin component for forming the primer layer
- a polyamide epoxy resin, a methylolated melamine resin, a dialdehyde-based crosslinking agent, a metal chelate compound-based crosslinking agent, or the like is preferably used as the crosslinking agent.
- the ratio of the resin component to the crosslinking agent in the primer layer forming coating solution is within the range of about 0.1 to 100 parts by weight of the crosslinking agent with respect to 100 parts by weight of the resin component. And the like, and it is preferable to select from the range of about 0.1 to 50 parts by weight.
- the primer layer forming coating solution preferably has a solid content concentration of about 1 to 25% by weight.
- the thickness of the primer layer is preferably about 0.05 to 1 ⁇ m, more preferably 0.1 to 0.4 ⁇ m.
- the thickness is less than 0.05 ⁇ m, the effect of improving the adhesion between the base film 30 and the polyvinyl alcohol resin layers 61 and 62 is small, and when the thickness is more than 1 ⁇ m, it is disadvantageous for making the polarizing plate thin.
- the method of applying the primer layer forming coating solution to the base film 30 can be the same as the coating solution for forming the polyvinyl alcohol-based resin layer.
- the primer layer is applied to the surface (one surface or both surfaces of the base film 30) to which the coating liquid for forming the polyvinyl alcohol-based resin layer is applied.
- the drying temperature and drying time of the coating layer comprising the primer layer forming coating solution are set according to the type of solvent contained in the coating solution.
- the drying temperature is, for example, 50 to 200 ° C., preferably 60 to 150 ° C. When the solvent contains water, the drying temperature is preferably 80 ° C. or higher.
- the drying time is, for example, 30 seconds to 20 minutes.
- the order of application to the base film 30 is not particularly limited.
- a polyvinyl alcohol resin layer is formed on both sides.
- the primer layer and the polyvinyl alcohol-based resin layer are sequentially formed on one surface of the base film 30. May be.
- Stretching step S20 With reference to FIG. 5, this process extends
- the stretching process is usually uniaxial stretching.
- the stretching ratio of the laminated film 100 can be appropriately selected depending on the desired polarization characteristics, but is preferably more than 5 times and not more than 17 times, more preferably more than 5 times the original length of the laminated film 100. 8 times or less.
- the draw ratio is 5 times or less, the polyvinyl alcohol resin layers 61 and 62 are not sufficiently oriented, and the degree of polarization of the polarizers 51 and 52 may not be sufficiently high.
- the draw ratio exceeds 17 times, the film is likely to be broken during stretching, and the thickness of the stretched film 200 becomes unnecessarily thin, and the workability and handleability in subsequent processes may be reduced.
- the stretching process is not limited to one-stage stretching, and can be performed in multiple stages.
- all of the multistage stretching processes may be performed continuously before the dyeing process S30, or the second and subsequent stretching processes may be performed simultaneously with the dyeing process and / or the crosslinking process in the dyeing process S30.
- the stretching treatment may be longitudinal stretching that extends in the film longitudinal direction (film transport direction), and may be lateral stretching or oblique stretching that extends in the film width direction.
- the longitudinal stretching method include inter-roll stretching using a roll, compression stretching, stretching using a chuck (clip), and the like
- examples of the lateral stretching method include a tenter method.
- the stretching treatment either a wet stretching method or a dry stretching method can be adopted. However, it is preferable to use the dry stretching method because the stretching temperature can be selected from a wide range.
- the stretching temperature is set to be equal to or higher than the temperature at which the polyvinyl alcohol-based resin layers 61 and 62 and the entire base film 30 can be stretched, and preferably the phase transition temperature (melting point or glass transition temperature) of the base film 30. ) In the range of ⁇ 30 ° C. to + 30 ° C., more preferably in the range of ⁇ 30 ° C. to + 5 ° C., and still more preferably in the range of ⁇ 25 ° C. to + 0 ° C.
- the phase transition temperature means the highest phase transition temperature among the phase transition temperatures exhibited by the plurality of resin layers.
- the stretching temperature is lower than the phase transition temperature of ⁇ 30 ° C., it is difficult to achieve a high-magnification stretching of more than 5 times, or the fluidity of the base film 30 is too low and the stretching process tends to be difficult.
- the stretching temperature exceeds + 30 ° C. of the phase transition temperature, the fluidity of the base film 30 is too large and stretching tends to be difficult.
- the drawing temperature is within the above range, and more preferably 120 ° C. or higher. This is because when the stretching temperature is 120 ° C. or higher, there is no difficulty in the stretching treatment even at a high stretching ratio of more than 5 times.
- a zone heating method for example, a method in which hot air is blown and heated in a stretching zone such as a heating furnace adjusted to a predetermined temperature
- a heater heating method a method in which infrared heaters, halogen heaters, panel heaters, etc. are installed above and below the laminated film 100 and heated by radiant heat.
- the zone heating method is preferable from the viewpoint of the uniformity of the stretching temperature.
- the two nip roll pairs may be installed in the temperature-controlled stretching zone or outside the stretching zone, but they are installed outside the stretching zone to prevent adhesion between the laminated film 100 and the nip roll. Is preferred.
- the stretching temperature means the atmospheric temperature in the zone (for example, in the heating furnace) in the case of the zone heating method, and means the atmospheric temperature in the furnace in the case of heating in the furnace also in the heater heating method. Moreover, in the case of the method of heating roll itself, the surface temperature of a roll is meant.
- a preheat treatment step for preheating the laminated film 100 may be provided.
- the preheating method the same method as the heating method in the stretching process can be used.
- preheating may be performed at any timing before passing through the upstream nip roll, during passing, or after passing.
- preheating is preferably performed at a timing before passing through the hot roll.
- preheating is preferably performed at a timing before increasing the distance between chucks.
- the preheating temperature is preferably in the range of ⁇ 50 ° C. to ⁇ 0 ° C. of the stretching temperature, and more preferably in the range of ⁇ 40 ° C. to ⁇ 10 ° C. of the stretching temperature.
- a heat setting treatment step may be provided after the stretching treatment in the stretching step S20.
- the heat setting process is a process in which heat treatment is performed at a temperature equal to or higher than the crystallization temperature while maintaining the tensioned state with the end of the stretched film 200 held by a clip. By this heat setting treatment, crystallization of the polyvinyl alcohol-based resin layers 61 ′ and 62 ′ is promoted.
- the temperature of the heat setting treatment is preferably in the range of ⁇ 0 ° C. to ⁇ 80 ° C. of the stretching temperature, and more preferably in the range of ⁇ 0 ° C. to ⁇ 50 ° C. of the stretching temperature.
- this step is a step in which the polyvinyl alcohol resin layers 61 ′ and 62 ′ of the stretched film 200 are dyed with a dichroic dye and adsorbed and oriented to obtain polarizers 51 and 52. .
- the polarizing laminated film 300 in which the polarizers 51 and 52 are laminated on both surfaces of the base film 30 ′ is obtained.
- the dyeing step can be performed by immersing the entire stretched film 200 in a solution (dye solution) containing a dichroic dye.
- a solution in which the above dichroic dye is dissolved in a solvent can be used.
- a solvent for the dyeing solution water is generally used, but an organic solvent compatible with water may be further added.
- the concentration of the dichroic dye in the dyeing solution is preferably 0.01 to 10% by weight, more preferably 0.02 to 7% by weight, and further preferably 0.025 to 5% by weight. preferable.
- iodine When iodine is used as the dichroic dye, it is preferable to further add an iodide to the dyeing solution containing iodine because the dyeing efficiency can be further improved.
- iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Is mentioned.
- the concentration of iodide in the dyeing solution is preferably 0.01 to 20% by weight. Of the iodides, it is preferable to add potassium iodide.
- the ratio of iodine to potassium iodide is preferably in the range of 1: 5 to 1: 100, more preferably in the range of 1: 6 to 1:80. Preferably, it is in the range of 1: 7 to 1:70.
- the immersion time of the stretched film 200 in the dyeing solution is usually in the range of 15 seconds to 15 minutes, preferably 30 seconds to 3 minutes.
- the temperature of the dyeing solution is preferably in the range of 10 to 60 ° C., more preferably in the range of 20 to 40 ° C.
- sucked to a polyvinyl alcohol-type resin layer can be orientated favorably.
- the dyeing step S30 is performed after the laminated film 100 is subjected to at least some stretching treatment. That is, the stretched film 200 obtained by subjecting the stretching process to the target magnification in the stretching process S20 can be used for the dyeing process S30, and after performing the stretching process at a lower ratio than the target in the stretching process S20. In the dyeing step S30, the stretching process can be performed until the total stretching ratio reaches the target ratio.
- the dyeing step S30 can include a cross-linking treatment step performed subsequent to the dyeing treatment.
- the crosslinking treatment can be performed by immersing the dyed film in a solution containing a crosslinking agent (crosslinking solution).
- a crosslinking agent conventionally known substances can be used, and examples thereof include boron compounds such as boric acid and borax, glyoxal, and glutaraldehyde.
- a crosslinking agent may be used individually by 1 type, and may use 2 or more types together.
- the crosslinking solution can be a solution in which a crosslinking agent is dissolved in a solvent.
- a solvent for example, water can be used, but an organic solvent compatible with water may be further included.
- the concentration of the crosslinking agent in the crosslinking solution is preferably in the range of 1 to 20% by weight, more preferably in the range of 6 to 15% by weight.
- the crosslinking solution can contain iodide.
- iodide By adding iodide, the polarization performance in the plane of the polarizers 51 and 52 can be made more uniform.
- iodide include potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide, and titanium iodide. Is mentioned.
- the concentration of iodide in the cross-linking solution is preferably 0.05 to 15% by weight, and more preferably 0.5 to 8% by weight.
- the immersion time of the dyed film in the crosslinking solution is usually 15 seconds to 20 minutes, preferably 30 seconds to 15 minutes.
- the temperature of the crosslinking solution is preferably in the range of 10 to 90 ° C.
- the crosslinking treatment can be performed simultaneously with the dyeing treatment by blending a crosslinking agent in the dyeing solution. Further, a stretching process may be performed during the crosslinking process.
- the specific mode for carrying out the stretching treatment during the crosslinking treatment is as described above. Moreover, you may perform the process immersed in a crosslinking solution 2 or more times using 2 or more types of crosslinking solutions from which a composition differs.
- the washing process usually includes a water washing process.
- the water washing treatment can be performed by immersing the film after the dyeing treatment or after the crosslinking treatment in pure water such as ion exchange water or distilled water.
- the water washing temperature is usually in the range of 3 to 50 ° C., preferably 4 to 20 ° C.
- the immersion time in water is usually 2 to 300 seconds, preferably 3 to 240 seconds.
- the washing step may be a combination of a water washing step and a washing step with an iodide solution.
- liquids such as methanol, ethanol, isopropyl alcohol, butanol, and propanol can be appropriately contained in the cleaning liquid used in the water cleaning step and / or the cleaning process using the iodide solution.
- any appropriate method such as natural drying, blow drying, and heat drying can be adopted.
- the drying temperature is usually 20 to 95 ° C.
- the drying time is usually about 1 to 15 minutes.
- this process is a protective film on the polarizer 51 of the polarizing laminate film 300, that is, on the surface opposite to the base film 30 ′ side of the polarizer 51 via an adhesive layer. It is the process of bonding 10 and obtaining the bonding film 400.
- the protective film 10 is bonded to the polarizer 51 through the adhesive layer 15.
- the bonding of the protective film through the adhesive layer is performed by, for example, applying an adhesive to the bonding surface of the protective film 10 and / or the polarizer 51 using a known means, and then applying the adhesive coating layer.
- stacking the protective film 10 and the polarizer 5 through and bonding using a bonding roll etc. is mentioned.
- a curing step is performed in which the photocurable adhesive is cured by irradiating active energy rays after the above-described pasting.
- the type of the active energy ray is not particularly limited, but an active energy ray (ultraviolet ray) having a peak wavelength at a wavelength of 400 nm or less is preferable, and UV-B having a peak wavelength between 280 and 320 nm is more preferable.
- the light source of the active energy ray is not particularly limited, but a high pressure mercury lamp, a low pressure mercury lamp, a medium pressure mercury lamp, an ultrahigh pressure mercury lamp, a chemical lamp, a black light lamp, a microwave excitation mercury lamp, a metal halide lamp, etc. are preferably used. It is done.
- the light irradiation intensity to the photocurable adhesive is appropriately determined depending on the composition of the photocurable adhesive, but the irradiation intensity in the wavelength region effective for activating the polymerization initiator is 0.1 to 6000 mW / cm 2 . It is preferable to set so as to be. When the irradiation intensity is 0.1 mW / cm 2 or more, the reaction time does not become too long, and when the irradiation intensity is 6000 mW / cm 2 or less, the light emitted from the light source and the light generated by the curing of the photocurable adhesive There is little possibility of causing yellowing of the curable adhesive and deterioration of the polarizers 51 and 52.
- the light irradiation time to the photocurable adhesive is also appropriately determined depending on the composition of the photocurable adhesive, and the integrated light amount expressed as the product of the irradiation intensity and the irradiation time is 10 to 10,000 mJ / cm 2 . It is preferable to set so as to be.
- the integrated light amount is 10 mJ / cm 2 or more, a sufficient amount of active species derived from the polymerization initiator can be generated to advance the curing reaction more reliably, and when it is 10000 mJ / cm 2 or less, the irradiation time is long. It does not become too much, and good productivity can be maintained.
- the surface of the protective film 10 on the side of the polarizer 51 is subjected to plasma treatment, corona treatment, ultraviolet irradiation treatment, frame in order to improve adhesion to the polarizer 51.
- Surface treatments easily adhesive treatment
- plasma treatment, corona treatment or saponification treatment is preferably performed.
- plasma treatment or corona treatment is usually performed.
- a saponification process is normally performed.
- the saponification treatment include a method of immersing in an alkaline aqueous solution such as sodium hydroxide or potassium hydroxide.
- This step is a step of peeling and removing the base film 30 ′ (and the polarizer 52) from the bonding film 400 obtained by bonding the protective film. Through this step, the polarizing plate 1 with a single-sided protective film in which the protective film 10 is laminated on one side of the polarizer 51 can be obtained.
- the method for peeling and removing the base film 30 ′ is not particularly limited, and can be peeled by the same method as the peeling step of a separator (peeling film) performed with a normal pressure-sensitive adhesive polarizing plate.
- the substrate film 30 ′ may be peeled off as it is after the bonding step S ⁇ b> 40, or may be wound once in a roll after the bonding step S ⁇ b> 40 and peeled off while being unwound in the subsequent steps.
- the method for achieving the absorbance of the polarizer defined in the present invention is not particularly limited.
- control by adjusting the potassium iodide content in the staining solution used in the staining step, and / or the crosslinking step By carrying out the control by adjusting the boric acid content and potassium iodide content in the crosslinking solution used in the above, the absorbance of the polarizer can be controlled efficiently.
- the light absorbency of a polarizer can be controlled efficiently also by the temperature of the washing
- the potassium iodide content in the staining solution varies depending on the method of dyeing, but the amount of potassium iodide is preferably 10 parts by weight or less, more preferably 7 parts by weight with respect to 100 parts by weight of the solvent (such as water). Part or less, more preferably 5 parts by weight or less.
- the absorbance of the polarizer can be easily controlled within the range of the present invention.
- the crosslinking process is carried out in two stages, and by adjusting the ratio of boric acid content and potassium iodide content in the second tank crosslinking solution, it is efficient.
- the absorbance of the polarizer can be controlled within the range of the present invention.
- the boric acid content is preferably 5.0 to 10.0 parts by weight with respect to 100 parts by weight of the solvent (such as water), and the potassium iodide content Is preferably 10 parts by weight or less, more preferably 7 parts by weight or less, and still more preferably 5 parts by weight or less.
- the absorbance of the polarizer can be controlled efficiently by relatively reducing the potassium iodide.
- the absorbance of the polarizer tends to be controlled within the range of the present invention even if the number of parts of potassium iodide is relatively large.
- the temperature of the cleaning liquid is raised too much, there is a problem that the hue in crossed Nicols becomes extremely blue or yellowing occurs during the heat resistance test. Therefore, the cleaning process is performed in two stages using a cleaning tank and a cleaning shower, the temperature of the cleaning liquid in the cleaning tank is set to a relatively low temperature, and the temperature of the cleaning liquid ejected from the cleaning shower is set to a relatively high temperature. It is preferable.
- the temperature of the cleaning liquid in the cleaning tank is preferably set to 5 to 13 ° C.
- the temperature of the cleaning liquid ejected from the cleaning shower is preferably set to 13 to 20 ° C.
- the time for the washing step is about 5 to 60 seconds in total.
- the final total draw ratio is preferably 6.0 times or less.
- the final total draw ratio is preferably 5.0 times or more.
- the stretching temperature is preferably 170 ° C. or lower.
- the polarizing plate of the present invention can be applied to a display device.
- this display device can include display cell 4 and polarizing plate 1 according to the present invention, which is disposed on at least one surface thereof.
- the polarizing plate 1 can be disposed and bonded onto the display cell 4 using an adhesive layer 2 provided on the outer surface of the polarizer 5.
- the protective film 10 of the polarizing plate 1 forms the outer surface (typically the outermost surface) of the display device.
- a typical example of the display device is a liquid crystal display device in which the display cell 4 is a liquid crystal cell, but may be another display device such as an organic EL device.
- the polarizing plate may be disposed on at least one surface of the display cell 4, but may be disposed on both surfaces.
- polarizing plates are usually disposed on both sides of the liquid crystal cell.
- the polarizing plates on both sides may be the polarizing plates according to the present invention, or only one polarizing plate may be the polarizing plates according to the present invention.
- the polarizing plate according to the present invention may be a polarizing plate on the front side (viewing side) or a polarizing plate on the rear side (backlight side) based on the liquid crystal cell.
- a conventionally known type of liquid crystal cell can be used.
- Example 1 (1) Primer layer forming step Polyvinyl alcohol powder (“Z-200” manufactured by Nippon Synthetic Chemical Industry Co., Ltd., average polymerization degree 1100, saponification degree 99.5 mol%) was dissolved in 95 ° C. hot water, A polyvinyl alcohol aqueous solution having a concentration of 3% by weight was prepared. The resulting aqueous solution was mixed with a crosslinking agent (“Smiles Resin 650” manufactured by Taoka Chemical Co., Ltd.) at a ratio of 5 parts by weight to 6 parts by weight of the polyvinyl alcohol powder to form a primer layer forming coating solution. Got.
- a crosslinking agent (“Smiles Resin 650” manufactured by Taoka Chemical Co., Ltd.)
- an unstretched polypropylene (PP) film (melting point: 163 ° C.) having a thickness of 90 ⁇ m was prepared as a base film, and both sides of the base film were subjected to corona treatment. Then, the primer layer-forming coating solution is applied to one corona-treated surface of the base film using a small-diameter gravure coater and dried at 80 ° C. for 10 minutes to form a primer layer having a thickness of 0.2 ⁇ m. did. Further, a similar primer layer was formed on the opposite surface of the base film.
- PP polypropylene
- the stretched film prepared in the above (3) is about 30 ° C. dyed aqueous solution containing iodine and potassium iodide (containing 0.6 parts by weight iodine and 10 parts by weight potassium iodide per 100 parts by weight water). After the polyvinyl alcohol resin layer was dyed for 180 seconds, the excess dye solution was washed away with pure water at 10 ° C.
- a crosslinking treatment was performed by immersing in a crosslinking aqueous solution (containing 9.5 parts by weight of boric acid and 4 parts by weight of potassium iodide per 100 parts by weight of water) for 60 seconds. Thereafter, the film was washed with pure water at 10 ° C. for 10 seconds and finally dried at 40 ° C. for 300 seconds to obtain a polarizing laminated film comprising a polarizer / primer layer / base film / primer layer / polarizer. Both polarizers had a thickness of 6.7 ⁇ m.
- polarizing plate (bonding process and peeling process)
- a cyclic polyolefin resin film (“ZD12” manufactured by Nippon Zeon Co., Ltd., thickness 50 ⁇ m) was prepared as a protective film disposed on the outside (viewing side) when the polarizing plate was disposed on the display cell.
- the protective film had a light transmittance of 2.6% at a wavelength of 365 nm.
- the light transmittance was measured using a spectrophotometer (UV2450) manufactured by Shimadzu Corporation.
- a photocurable adhesive (“KR-70T” manufactured by ADEKA) was applied to the corona-treated surface using a small-diameter gravure coater, After arrange
- the photocurable adhesive is irradiated with ultraviolet rays so that the cumulative amount of UVB light is 250 mJ / cm 2 (that is, ultraviolet rays are 2
- the adhesive layer is cured by passing through a single polarizer and the adhesive layer is cured to form a protective film / adhesive layer / polarizer / primer layer / base film / primer layer. /
- the bonding film which consists of a layer structure of a polarizer was obtained (bonding process).
- the layer structure of the base film / primer layer / polarizer (polarizer on the side opposite to the protective film) was peeled off from the obtained laminated film (peeling step).
- the layer structure including the base film was easily peeled to obtain a polarizing plate with a single-sided protective film having a layer structure of protective film / adhesive layer / polarizer / primer layer.
- Example 1 except that the amounts of boric acid and potassium iodide contained in the second aqueous crosslinked solution (parts per 100 parts by weight of water) and the temperature of the washing tank and the washing shower were as shown in Table 1. Similarly, a polarizing laminate film and a polarizing plate were produced.
- the V7100 In measurement at wavelengths from 280 nm to 320 nm, the V7100 is equipped with a Glan-Thompson prism, which is a polarization separation element, but the sample film was placed so as to be in a crossed Nicol position with respect to the Glan-Thompson prism. And the average value of the transmittance when the sample film in that state was placed 90 degrees was determined, and this average value was used as the transmittance of the sample.
- Glan-Thompson prism which is a polarization separation element
- the maximum absorbance for each sample film is shown in Table 1.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Polarising Elements (AREA)
- Laminated Bodies (AREA)
- Liquid Crystal (AREA)
Abstract
Description
[2] 上記[1]に記載の偏光子と、光透過性接着剤の硬化物からなる接着剤層を介して前記偏光子に積層された保護フィルムとを備える偏光板。
[3] 前記保護フィルムの波長365nmにおける光線透過率が5%未満である、上記[2]に記載の偏光板。
[4] 前記光硬化性接着剤は、最大吸収波長が280~320nmの間にある光重合開始剤を含有する、上記[2]または[3]に記載の偏光板。
[5] 前記偏光子の厚みが10μm以下である、上記[2]~[4]のいずれかに記載の偏光板。
[6] 基材フィルムと、該基材フィルムの両面に設けられた上記[1]に記載の偏光子とを備える偏光性積層フィルム。
図1は、本発明に係る偏光板の層構成の一例を示す概略断面図である。図1に示される偏光板1のように、本発明の偏光板は、偏光子5と、その一方の面に接着剤層15を介して積層される保護フィルム10とを備える片面保護フィルム付偏光板であることができる。図2は、図1に示される偏光板を表示用セル上に配置したときの状態を示す概略断面図である。図2に示されるように、保護フィルム10は、偏光板1を表示用セル4上に配置する際に外側に配置される保護フィルムであり、偏光板1を表示用セル4上に配置したときに、典型的には最外面を形成する保護フィルムである。偏光板1は、偏光子5の外面に設けた粘着剤層2を用いて表示用セル4上に配置・貼合することができる。
本発明において、偏光子の波長280~320nmにおける最大吸光度は0.70以下であり、より好ましくは0.68以下である。
吸光度 = -log10(T/T0)
ここで、T0は入射光強度、Tは透過光強度である。
ケン化度(モル%)=100×(水酸基の数)÷(水酸基の数+酢酸基の数)
で定義される。ケン化度は、JIS K 6726(1994)に準拠して求めることができる。ケン化度が高いほど、水酸基の割合が高いことを示しており、従って結晶化を阻害する酢酸基の割合が低いことを示している。
保護フィルム10はそれぞれ、熱可塑性樹脂、例えば、鎖状ポリオレフィン系樹脂(ポリプロピレン系樹脂等)、環状ポリオレフィン系樹脂(ノルボルネン系樹脂等)のようなポリオレフィン系樹脂;セルローストリアセテート、セルロースジアセテートのようなセルロースエステル系樹脂;ポリエチレンテレフタレート、ポリエチレンナフタレート、ポリブチレンテレフタレートのようなポリエステル系樹脂;ポリカーボネート系樹脂;(メタ)アクリル系樹脂;又はこれらの混合物、共重合物等からなる透明樹脂フィルムであることができる。
接着剤層15は、光硬化性接着剤の硬化物からなる層である。
図2に示されるように、偏光子5の外面(接着剤層15とは反対側の面)に、偏光板1を他の部材(例えば、表示装置の表示用セル4)に貼合するための粘着剤層2を積層してもよい。
偏光板1は、保護フィルム10又は偏光子5上に積層される他の光学層をさらに含むことができる。他の光学層としては、ある種の偏光光を透過し、それと逆の性質を示す偏光光を反射する反射型偏光フィルム;表面に凹凸形状を有する防眩機能付フィルム;表面反射防止機能付フィルム;表面に反射機能を有する反射フィルム;反射機能と透過機能とを併せ持つ半透過反射フィルム;視野角補償フィルムなどが挙げられる。
本発明の偏光板は、例えば図3に示される方法によって好適に製造することができる。図3に示される偏光板の製造方法は、保護フィルム付の偏光板1を製造するための方法であり、下記工程:
(1)基材フィルムの少なくとも一方の面にポリビニルアルコール系樹脂を含有する塗工液を塗工した後、乾燥させることによりポリビニルアルコール系樹脂層を形成して積層フィルムを得る樹脂層形成工程S10、
(2)積層フィルムを延伸して延伸フィルムを得る延伸工程S20、
(3)延伸フィルムのポリビニルアルコール系樹脂層を二色性色素で染色して偏光子を形成することにより偏光性積層フィルムを得る染色工程S30、
(4)偏光性積層フィルムの偏光子上に、接着剤層を介して保護フィルムのいずれか一方を貼合して貼合フィルムを得る貼合工程S40、
(5)貼合フィルムから基材フィルムを剥離除去して片面保護フィルム付偏光板を得る剥離工程S50
をこの順で含む。
図4を参照して、本工程は、基材フィルム30の両面にポリビニルアルコール系樹脂層61,62を形成して積層フィルム100を得る工程である。このポリビニルアルコール系樹脂層61,62は、延伸工程S20及び染色工程S30を経て偏光子51,52となる層である。ポリビニルアルコール系樹脂層61,62は、ポリビニルアルコール系樹脂を含有する塗工液を基材フィルム30の両面に塗工し、塗工層を乾燥させることにより形成することができる。このような塗工によりポリビニルアルコール系樹脂層を形成する方法は、薄膜の偏光子51,52を得やすい点で有利である。
基材フィルム30は熱可塑性樹脂から構成することができ、中でも透明性、機械的強度、熱安定性、延伸性等に優れる熱可塑性樹脂から構成することが好ましい。このような熱可塑性樹脂の具体例は、例えば、鎖状ポリオレフィン系樹脂、環状ポリオレフィン系樹脂(ノルボルネン系樹脂等)のようなポリオレフィン系樹脂;ポリエステル系樹脂;(メタ)アクリル系樹脂;セルローストリアセテート、セルロースジアセテートのようなセルロースエステル系樹脂;ポリカーボネート系樹脂;ポリビニルアルコール系樹脂;ポリ酢酸ビニル系樹脂;ポリアリレート系樹脂;ポリスチレン系樹脂;ポリエーテルスルホン系樹脂;ポリスルホン系樹脂;ポリアミド系樹脂;ポリイミド系樹脂;及びこれらの混合物、共重合物を含む。
塗工液は、好ましくはポリビニルアルコール系樹脂の粉末を良溶媒(例えば水)に溶解させて得られるポリビニルアルコール系樹脂溶液である。ポリビニルアルコール系樹脂の詳細は、上述のとおりである。
上記塗工液を基材フィルム30に塗工する方法は、ワイヤーバーコーティング法;リバースコーティング、グラビアコーティングのようなロールコーティング法;ダイコート法;カンマコート法;リップコート法;スピンコーティング法;スクリーンコーティング法;ファウンテンコーティング法;ディッピング法;スプレー法等の方法から適宜選択することができる。
プライマー層は、プライマー層形成用塗工液を基材フィルム30の表面に塗工した後、乾燥させることにより形成することができる。プライマー層形成用塗工液は、基材フィルム30とポリビニルアルコール系樹脂層61,62との両方にある程度強い密着力を発揮する成分を含む。プライマー層形成用塗工液は通常、このような密着力を付与する樹脂成分と溶媒とを含有する。樹脂成分としては、好ましくは透明性、熱安定性、延伸性等に優れる熱可塑樹脂が用いられ、例えば、(メタ)アクリル系樹脂、ポリビニルアルコール系樹脂等が挙げられる。中でも、良好な密着力を与えるポリビニルアルコール系樹脂が好ましく用いられる。
図5を参照して、本工程は、基材フィルム30及びポリビニルアルコール系樹脂層61,62からなる積層フィルム100を延伸して、延伸された基材フィルム30’及びポリビニルアルコール系樹脂層61’,62’からなる延伸フィルム200を得る工程である。延伸処理は通常、一軸延伸である。
図6を参照して、本工程は、延伸フィルム200のポリビニルアルコール系樹脂層61’,62’を二色性色素で染色してこれを吸着配向させ、偏光子51,52とする工程である。本工程を経て基材フィルム30’の両面に偏光子51,52が積層された偏光性積層フィルム300が得られる。
図7を参照して、本工程は、偏光性積層フィルム300の偏光子51上、すなわち、偏光子51の基材フィルム30’側とは反対側の面に、接着剤層を介して保護フィルム10を貼合して貼合フィルム400を得る工程である。
本工程は、保護フィルムを貼合して得られた貼合フィルム400から基材フィルム30’(および偏光子52)を剥離除去する工程である。この工程を経て、偏光子51の片面に保護フィルム10が積層された片面保護フィルム付の偏光板1を得ることができる。
本発明で規定する偏光子の吸光度を達成する方法は、特に制約されるものではないが、例えば、染色工程で用いる染色液中のヨウ化カリウム含有量の調整による制御、および/または、架橋工程で用いる架橋溶液中のホウ酸含有量およびヨウ化カリウム含有量の調整による制御を実施することで、効率よく偏光子の吸光度を制御できる。また、染色工程における架橋工程後の洗浄工程で用いる洗浄液の温度、洗浄液中での滞留時間によっても、効率よく偏光子の吸光度を制御できる。
本発明の偏光板は、表示装置に適用することができる。図2を参照して、この表示装置は、表示用セル4と、その少なくとも一方の面に配置される、上述の本発明に係る偏光板1とを含むものであることができる。
(1)プライマー層形成工程
ポリビニルアルコール粉末(日本合成化学工業(株)製の「Z-200」、平均重合度1100、ケン化度99.5モル%)を95℃の熱水に溶解し、濃度3重量%のポリビニルアルコール水溶液を調製した。得られた水溶液に架橋剤(田岡化学工業(株)製の「スミレーズレジン650」)をポリビニルアルコール粉末6重量部に対して5重量部の割合で混合して、プライマー層形成用塗工液を得た。
ポリビニルアルコール粉末((株)クラレ製の「PVA124」、平均重合度2400、ケン化度98.0~99.0モル%)を95℃の熱水に溶解し、濃度8重量%のポリビニルアルコール水溶液を調製し、これをポリビニルアルコール系樹脂層形成用塗工液とした。
上記(2)で作製した積層フィルムに対して、フローティングの縦一軸延伸装置を用いて160℃で5.8倍の自由端一軸延伸を実施し、延伸フィルムを得た。延伸後のポリビニルアルコール系樹脂層の厚みは共に6.1μmであった。
上記(3)で作製した延伸フィルムを、ヨウ素とヨウ化カリウムとを含む30℃の染色水溶液(水100重量部あたりヨウ素を0.6重量部、ヨウ化カリウムを10重量部含む。)に約180秒間浸漬してポリビニルアルコール系樹脂層の染色処理を行った後、10℃の純水で余分な染色水溶液を洗い流した。
偏光板を表示用セル上に配置する際に外側(視認側)に配置される保護フィルムとして、環状ポリオレフィン系樹脂フィルム(日本ゼオン(株)製の「ZD12」、厚み50μm)を用意した。この保護フィルムの波長365nmにおける光線透過率は2.6%であった。なお、光線透過率の測定は、(株)島津製作所製の分光光度計(UV2450)を用いて実施した。
第2架橋水溶液に含まれるホウ酸およびヨウ化カリウムの量(水100重量部あたりの部数)と、水洗槽および水洗シャワーの温度を表1に示されるとおりとしたこと以外は、実施例1と同様にして偏光性積層フィルムおよび偏光板を作製した。
実施例1~6および比較例1~4で得られた偏光性積層フィルム(保護フィルムが貼合されていない)の片側の偏光子を基材フィルムより剥離し、基材フィルム上に残った方の偏光子(すなわち、「基材フィルム/プライマー層/偏光子」の層構成からなる試料フィルム)について、吸光度を測定した。吸光度は吸光光度計(日本分光(株)製:V7100)を用いて測定し、波長280nmから波長320nmの各波長での測定を行った。V7100としては、紫外領域が測定できるタイプ(窓材が石英ガラスのもの)を用いた。波長280nmから波長320nmの各波長での測定において、V7100には偏光分離素子であるグラントムソンプリズムが設置されているが、試料フィルムを該グラントムソンプリズムに対してクロスニコル位置となるように配置したときの透過率と、その状態の試料フィルムを90度回して配置したときの透過率の平均値を求めて、この平均値を試料の透過率とした。
各波長における吸光度=-log10( 各波長における透過率(%) / 100)
そして、波長280nmから波長320nmにおける吸光度のうち、最大の値をその試料の最大吸光度として採用した。各試料フィルムについての最大吸光度を表1に示す。
実施例1~6および比較例1~4で得られた偏光板の保護フィルムと反対側の面を、感圧式接着剤(リンテック(株)製:P-3132)を用いてガラス板に貼合し、保護フィルム側からカッターの刃を用いて、1mm角の升目が100升形成されるように保護フィルムのみに碁盤目状の切り込みを入れ、「JIS D0202 4.15 碁盤目付着性試験方法」に準じたクロスカット試験を実施した。試験後に剥がれずに残った升目の数を表1に示す。
接着剤層における光硬化性接着剤のモノマー反応率の評価のために、耐湿熱試験を実施した。接着剤層中に未反応モノマーが残っている場合には、耐湿熱試験で偏光子の脱色が起こる。実施例1~6および比較例1~4で得られた偏光板の保護フィルムと反対側の面を、粘着剤(リンテック(株)製:P-3132)を用いて無アルカリガラス板に貼合した後、温度80℃、湿度90%RHの環境下に48時間放置した。
Claims (6)
- 波長280~320nmにおける最大吸光度が0.70以下である偏光子。
- 請求項1に記載の偏光子と、光透過性接着剤の硬化物からなる接着剤層を介して前記偏光子に積層された保護フィルムとを備える偏光板。
- 前記保護フィルムの波長365nmにおける光線透過率が5%未満である、請求項2に記載の偏光板。
- 前記光硬化性接着剤は、最大吸収波長が280~320nmの間にある光重合開始剤を含有する、請求項2または3に記載の偏光板。
- 前記偏光子の厚みが10μm以下である、請求項2~4のいずれか1項に記載の偏光板。
- 基材フィルムと、該基材フィルムの両面に設けられた請求項1に記載の偏光子とを備える偏光性積層フィルム。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020167019490A KR101903869B1 (ko) | 2013-12-26 | 2014-12-19 | 편광자 및 이 편광자를 구비하는 편광판 및 편광성 적층 필름 |
JP2015554828A JP6279615B2 (ja) | 2013-12-26 | 2014-12-19 | 偏光子、ならびに、この偏光子を備える偏光板および偏光性積層フィルム |
CN201480071287.5A CN105849601B (zh) | 2013-12-26 | 2014-12-19 | 偏振器以及具有该偏振器的偏振板和偏振性层叠膜 |
US15/107,957 US10132975B2 (en) | 2013-12-26 | 2014-12-19 | Polarizing plate having a photo-curable adhesive |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013-269552 | 2013-12-26 | ||
JP2013269552 | 2013-12-26 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2015098734A1 true WO2015098734A1 (ja) | 2015-07-02 |
Family
ID=53478591
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2014/083672 WO2015098734A1 (ja) | 2013-12-26 | 2014-12-19 | 偏光子、ならびに、この偏光子を備える偏光板および偏光性積層フィルム |
Country Status (6)
Country | Link |
---|---|
US (1) | US10132975B2 (ja) |
JP (3) | JP6279615B2 (ja) |
KR (1) | KR101903869B1 (ja) |
CN (1) | CN105849601B (ja) |
TW (1) | TWI630111B (ja) |
WO (1) | WO2015098734A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108152876A (zh) * | 2016-12-02 | 2018-06-12 | 住友化学株式会社 | 偏振膜及偏振性层叠膜的制造方法 |
KR20180123215A (ko) * | 2016-03-09 | 2018-11-15 | 닛토덴코 가부시키가이샤 | 경화성 수지 조성물, 편광 필름 및 그 제조 방법, 광학 필름 그리고 화상 표시 장치 |
US11061175B2 (en) | 2016-05-17 | 2021-07-13 | Nitto Denko Corporation | Polarizing film, method for producing same, optical film, image display device, and adhesion improvement-treated polarizer |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR102476698B1 (ko) * | 2018-10-15 | 2022-12-14 | 닛토덴코 가부시키가이샤 | 위상차층 부착 편광판 및 이를 이용한 화상 표시 장치 |
KR102659449B1 (ko) * | 2020-08-04 | 2024-04-19 | 삼성에스디아이 주식회사 | 편광판 및 이를 포함하는 광학표시장치 |
JP7159375B2 (ja) * | 2021-03-10 | 2022-10-24 | 住友化学株式会社 | 光学積層体及び表示装置、並びに光学積層体の製造方法 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010091603A (ja) * | 2008-10-03 | 2010-04-22 | Sumitomo Chemical Co Ltd | 偏光板および液晶表示装置 |
JP2012144690A (ja) * | 2010-12-24 | 2012-08-02 | Nitto Denko Corp | 活性エネルギー線硬化型接着剤組成物、偏光板、光学フィルムおよび画像表示装置 |
JP2012159778A (ja) * | 2011-02-02 | 2012-08-23 | Sumitomo Chemical Co Ltd | 偏光性積層フィルム、偏光板または基材フィルム付き偏光板の製造方法、および、両面積層フィルム、両面偏光性積層フィルム、両面貼合フィルム、片面貼合フィルム |
Family Cites Families (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2825157B2 (ja) | 1988-03-22 | 1998-11-18 | ジェイエスアール株式会社 | 重合体の製造方法 |
JP2881751B2 (ja) | 1989-03-10 | 1999-04-12 | 三井化学株式会社 | メッキ用組成物およびメッキ物 |
JP2712643B2 (ja) | 1989-10-06 | 1998-02-16 | 日本合成ゴム株式会社 | 熱可塑性樹脂成形品 |
JP3825508B2 (ja) | 1996-09-17 | 2006-09-27 | 住友化学株式会社 | ヨウ素系偏光フィルムの製造方法 |
JP4726145B2 (ja) | 2007-01-11 | 2011-07-20 | 日東電工株式会社 | 偏光板用接着剤、偏光板、その製造方法、光学フィルムおよび画像表示装置 |
JP5204608B2 (ja) | 2007-10-10 | 2013-06-05 | 日東電工株式会社 | 偏光板、光学フィルムおよび画像表示装置 |
JP2009134121A (ja) | 2007-11-30 | 2009-06-18 | Nitto Denko Corp | 偏光板、光学フィルムおよび画像表示装置 |
JP2009139585A (ja) | 2007-12-05 | 2009-06-25 | Nitto Denko Corp | 偏光板、光学フィルムおよび画像表示装置 |
JP2010085626A (ja) | 2008-09-30 | 2010-04-15 | Sumitomo Chemical Co Ltd | 偏光板、ならびにそれを用いた液晶パネルおよび液晶表示装置 |
CN101713838A (zh) | 2008-10-03 | 2010-05-26 | 住友化学株式会社 | 偏振片和液晶显示装置 |
JP2010091602A (ja) | 2008-10-03 | 2010-04-22 | Sumitomo Chemical Co Ltd | 偏光板および液晶表示装置 |
JP5430126B2 (ja) * | 2008-11-13 | 2014-02-26 | キヤノン株式会社 | 偏光子 |
JP5337467B2 (ja) * | 2008-12-16 | 2013-11-06 | 日東電工株式会社 | 偏光板の製造方法 |
CN201615978U (zh) * | 2009-12-16 | 2010-10-27 | 深圳市三利谱光电科技有限公司 | 宽视角tft型液晶显示器用偏光片 |
KR20120002815A (ko) | 2010-07-01 | 2012-01-09 | 동우 화인켐 주식회사 | 편광자의 제조방법 |
WO2012050047A1 (ja) * | 2010-10-12 | 2012-04-19 | シャープ株式会社 | 表示装置 |
JP2012203211A (ja) | 2011-03-25 | 2012-10-22 | Sumitomo Chemical Co Ltd | 偏光板および液晶表示装置 |
CN102759758A (zh) * | 2011-04-21 | 2012-10-31 | 富士胶片株式会社 | 光学膜、偏振片和液晶显示装置 |
JP5682517B2 (ja) | 2011-09-12 | 2015-03-11 | コニカミノルタ株式会社 | 偏光板保護フィルム及び偏光板 |
JP5855947B2 (ja) * | 2012-01-12 | 2016-02-09 | 住友化学株式会社 | 光硬化性接着剤、それを用いた偏光板および積層光学部材 |
JP5840959B2 (ja) * | 2012-01-16 | 2016-01-06 | エムテックスマート株式会社 | 塗布方法及び装置 |
JP6327659B2 (ja) | 2012-03-30 | 2018-05-23 | 日東電工株式会社 | 偏光板のセットおよび液晶表示装置 |
JP6308721B2 (ja) | 2012-03-30 | 2018-04-11 | 日東電工株式会社 | 偏光フィルム、光学フィルムおよび画像表示装置 |
US20160003995A1 (en) * | 2013-03-21 | 2016-01-07 | Konica Minolta, Inc. | Optical film, circularly polarizing plate, and organic electroluminescent display device |
JPWO2014188935A1 (ja) * | 2013-05-21 | 2017-02-23 | コニカミノルタ株式会社 | 位相差フィルム、該位相差フィルムを用いた円偏光板および画像表示装置 |
-
2014
- 2014-12-19 US US15/107,957 patent/US10132975B2/en active Active
- 2014-12-19 WO PCT/JP2014/083672 patent/WO2015098734A1/ja active Application Filing
- 2014-12-19 KR KR1020167019490A patent/KR101903869B1/ko active IP Right Grant
- 2014-12-19 CN CN201480071287.5A patent/CN105849601B/zh active Active
- 2014-12-19 JP JP2015554828A patent/JP6279615B2/ja active Active
- 2014-12-25 TW TW103145448A patent/TWI630111B/zh active
-
2018
- 2018-01-16 JP JP2018005034A patent/JP6855398B2/ja active Active
-
2019
- 2019-11-26 JP JP2019213237A patent/JP2020042298A/ja active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2010091603A (ja) * | 2008-10-03 | 2010-04-22 | Sumitomo Chemical Co Ltd | 偏光板および液晶表示装置 |
JP2012144690A (ja) * | 2010-12-24 | 2012-08-02 | Nitto Denko Corp | 活性エネルギー線硬化型接着剤組成物、偏光板、光学フィルムおよび画像表示装置 |
JP2012159778A (ja) * | 2011-02-02 | 2012-08-23 | Sumitomo Chemical Co Ltd | 偏光性積層フィルム、偏光板または基材フィルム付き偏光板の製造方法、および、両面積層フィルム、両面偏光性積層フィルム、両面貼合フィルム、片面貼合フィルム |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20180123215A (ko) * | 2016-03-09 | 2018-11-15 | 닛토덴코 가부시키가이샤 | 경화성 수지 조성물, 편광 필름 및 그 제조 방법, 광학 필름 그리고 화상 표시 장치 |
KR102565069B1 (ko) | 2016-03-09 | 2023-08-09 | 닛토덴코 가부시키가이샤 | 경화성 수지 조성물, 편광 필름 및 그 제조 방법, 광학 필름 그리고 화상 표시 장치 |
US11061175B2 (en) | 2016-05-17 | 2021-07-13 | Nitto Denko Corporation | Polarizing film, method for producing same, optical film, image display device, and adhesion improvement-treated polarizer |
CN108152876A (zh) * | 2016-12-02 | 2018-06-12 | 住友化学株式会社 | 偏振膜及偏振性层叠膜的制造方法 |
JP2018091980A (ja) * | 2016-12-02 | 2018-06-14 | 住友化学株式会社 | 偏光フィルム及び偏光性積層フィルムの製造方法 |
TWI795379B (zh) * | 2016-12-02 | 2023-03-11 | 日商住友化學股份有限公司 | 偏光膜及偏光性積層膜之製造方法 |
Also Published As
Publication number | Publication date |
---|---|
JP6855398B2 (ja) | 2021-04-07 |
KR20160102478A (ko) | 2016-08-30 |
US20160320538A1 (en) | 2016-11-03 |
JP2018097373A (ja) | 2018-06-21 |
US10132975B2 (en) | 2018-11-20 |
CN105849601A (zh) | 2016-08-10 |
CN105849601B (zh) | 2019-04-12 |
TWI630111B (zh) | 2018-07-21 |
JP6279615B2 (ja) | 2018-02-14 |
JP2020042298A (ja) | 2020-03-19 |
JPWO2015098734A1 (ja) | 2017-03-23 |
TW201531405A (zh) | 2015-08-16 |
KR101903869B1 (ko) | 2018-10-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5932760B2 (ja) | 偏光子及びそれを含む偏光板 | |
JP5636134B2 (ja) | 積層フィルム、並びに、偏光性積層フィルムの製造方法及び偏光板の製造方法 | |
WO2012096079A1 (ja) | 偏光性積層フィルムの製造方法および偏光板の製造方法 | |
JP6855398B2 (ja) | 偏光板、貼合フィルム、及びこれらの製造方法 | |
KR101435358B1 (ko) | 편광성 적층 필름과 편광판의 제조 방법 | |
JP5996516B2 (ja) | 偏光子及びそれを含む偏光板 | |
WO2014065425A1 (ja) | 偏光性積層フィルムの製造方法および偏光板の製造方法 | |
JP6349082B2 (ja) | 偏光板及び表示装置 | |
KR101901479B1 (ko) | 편광판의 제조 방법 | |
JP6262514B2 (ja) | 偏光板 | |
JP6049600B2 (ja) | 偏光子及びそれを含む偏光板 | |
WO2014157730A1 (ja) | 偏光性積層フィルムの製造方法および偏光板の製造方法 | |
WO2014136984A1 (ja) | 偏光性積層フィルムの製造方法および偏光板の製造方法 | |
JP6653729B2 (ja) | 偏光板及び表示装置 | |
JP6342963B2 (ja) | 偏光板 | |
JP2018084827A (ja) | 偏光板 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 14874793 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2015554828 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15107957 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20167019490 Country of ref document: KR Kind code of ref document: A |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 14874793 Country of ref document: EP Kind code of ref document: A1 |