CN114167539A - Method and apparatus for producing polarizing film - Google Patents
Method and apparatus for producing polarizing film Download PDFInfo
- Publication number
- CN114167539A CN114167539A CN202111519263.XA CN202111519263A CN114167539A CN 114167539 A CN114167539 A CN 114167539A CN 202111519263 A CN202111519263 A CN 202111519263A CN 114167539 A CN114167539 A CN 114167539A
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- Prior art keywords
- film
- electromagnetic wave
- crosslinking
- polyvinyl alcohol
- alcohol resin
- Prior art date
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- Pending
Links
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- BHZRJJOHZFYXTO-UHFFFAOYSA-L potassium sulfite Chemical compound [K+].[K+].[O-]S([O-])=O BHZRJJOHZFYXTO-UHFFFAOYSA-L 0.000 description 1
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- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
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- DUNKXUFBGCUVQW-UHFFFAOYSA-J zirconium tetrachloride Chemical compound Cl[Zr](Cl)(Cl)Cl DUNKXUFBGCUVQW-UHFFFAOYSA-J 0.000 description 1
Images
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/12—Chemical modification
- C08J7/123—Treatment by wave energy or particle radiation
-
- 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
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
- B29C55/02—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of plates or sheets
- B29C55/04—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of plates or sheets uniaxial, e.g. oblique
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/24—Crosslinking, e.g. vulcanising, of macromolecules
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/28—Treatment by wave energy or particle radiation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L29/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal or ketal radical; Compositions of hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Compositions of derivatives of such polymers
- C08L29/02—Homopolymers or copolymers of unsaturated alcohols
- C08L29/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
-
- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
- D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
- D06P3/58—Material containing hydroxyl groups
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- 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
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- 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
- G02F1/133528—Polarisers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2329/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2329/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
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- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Mathematical Physics (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Textile Engineering (AREA)
- Polarising Elements (AREA)
Abstract
The invention provides a method and an apparatus for manufacturing a polarizing film, which can obtain a polarizing film with excellent optical characteristics and durability. A method for producing a polarizing film from a polyvinyl alcohol resin film, the polarizing film being produced by a method for producing a polarizing filmThe method for producing a film includes: a dyeing step of dyeing the polyvinyl alcohol resin film with a dichroic dye, a crosslinking step of crosslinking the polyvinyl alcohol resin film after the dyeing step with a crosslinking agent, an electromagnetic wave irradiation step of irradiating the polyvinyl alcohol resin film after the crosslinking step with an electromagnetic wave containing infrared rays, and a step of exposing the polyvinyl alcohol resin film after the irradiation with the electromagnetic wave to an absolute humidity of 80g/m3And a high humidity treatment step in the above atmosphere.
Description
The present application is a divisional application of application No. 201710701567.5 entitled "method and apparatus for producing polarizing film".
Technical Field
The present invention relates to a method and an apparatus for producing a polarizing film from a polyvinyl alcohol resin film.
Background
Polarizing plates are widely used as polarizing elements in image display devices such as liquid crystal display devices. A polarizing plate generally has a structure in which a transparent resin film (e.g., a protective film) is bonded to one surface or both surfaces of a polarizing film using an adhesive or the like.
The polarizing film is mainly manufactured by the following process: the method includes a step of immersing a raw material film made of a polyvinyl alcohol resin in a dyeing bath containing a dichroic dye such as iodine, a step of immersing the raw material film in a crosslinking bath containing a crosslinking agent such as boric acid, and the like, and a step of uniaxially stretching the film at any of the above-described stages. The uniaxial stretching includes: dry stretching in which stretching is performed in air, and wet stretching in which stretching is performed in a liquid such as the above-mentioned dyeing bath or crosslinking bath.
Since the polarizing film is crosslinked, it is likely to shrink when heated, and the durability may be insufficient. Further, when the stretch ratio is increased in order to improve the optical properties, shrinkage tends to occur, and the durability may be insufficient. Jp 2013-148806 a (patent document 1) discloses a polarizing film having excellent durability with a boron content as low as 1 to 3.5 wt%.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open publication No. 2013-148806
Disclosure of Invention
Problems to be solved by the invention
However, in the polarizing film, when the boron content is reduced, a sufficient degree of crosslinking cannot be obtained, and the optical properties may be reduced. The invention aims to provide a method and a device for manufacturing a polarizing film, which can obtain a polarizing film with excellent optical properties and durability in the method for manufacturing the polarizing film.
Means for solving the problems
The present invention provides a method and an apparatus for producing a polarizing film described below.
[ 1] A method for producing a polarizing film from a polyvinyl alcohol resin film, the method comprising:
a dyeing step of dyeing the polyvinyl alcohol resin film with a dichroic dye;
a crosslinking step of crosslinking the polyvinyl alcohol resin film after the dyeing step with a crosslinking agent;
an electromagnetic wave irradiation step of irradiating the polyvinyl alcohol resin film after the crosslinking step with an electromagnetic wave containing infrared rays; and
a high humidity treatment step of exposing the polyvinyl alcohol resin film irradiated with the electromagnetic wave to an absolute humidity of 80g/m3The above atmosphere.
The method for producing a polarizing film according to [ 1], further comprising a cleaning step of cleaning the polyvinyl alcohol resin film between the electromagnetic wave irradiation step and the high humidity treatment step.
[ 3 ] the method for producing a polarizing film according to [ 1] or [ 2], wherein in the electromagnetic wave irradiation step, a ratio of infrared radiation energy having a wavelength of more than 2 μm and not more than 4 μm in the electromagnetic wave is not less than 25% of total radiation energy.
The method for producing a polarizing film according to any one of [ 1] to [ 3 ], wherein the amount of heat of irradiation with the electromagnetic wave in the electromagnetic wave irradiation step is 100J/cm per unit volume of the polyvinyl alcohol resin film3Above and 50kJ/cm3The following.
The method for producing a polarizing film according to any one of [ 1] to [ 4 ], wherein the polyvinyl alcohol resin film is uniaxially stretched 1.04 to 1.2 times in the high-humidity treatment step.
[ 6 ] A polarizing film production apparatus for producing a polarizing film from a polyvinyl alcohol resin film, the polarizing film production apparatus comprising:
a dyeing section for dyeing the polyvinyl alcohol resin film with a dichroic dye;
a crosslinking section for crosslinking the dyed polyvinyl alcohol resin film with a crosslinking agent;
an electromagnetic wave irradiation unit that irradiates the polyvinyl alcohol resin film subjected to the crosslinking treatment with an electromagnetic wave containing infrared rays; and
a high humidity treatment part for exposing the polyvinyl alcohol resin film irradiated with the electromagnetic wave to an absolute humidity of 80g/m3The above atmosphere.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, a polarizing film production method and a polarizing film production apparatus capable of obtaining a polarizing film excellent in both optical characteristics and durability can be provided.
Drawings
Fig. 1 is a cross-sectional view schematically showing an example of the polarizing film manufacturing method and the polarizing film manufacturing apparatus used in the polarizing film manufacturing method of the present invention.
Fig. 2 is a graph showing a radiation energy spectrum of each electromagnetic wave irradiator.
Detailed Description
< method for producing polarizing film >
In the present invention, the polarizing film is obtained by orienting a uniaxially stretched polyvinyl alcohol resin film by adsorbing a dichroic dye (iodine or dichroic dye). The polyvinyl alcohol resin constituting the polyvinyl alcohol resin film is generally obtained by saponifying a polyvinyl acetate resin. The saponification degree thereof is usually about 85 mol% or more, preferably about 90 mol% or more, more preferably about 99 mol% or more. The polyvinyl acetate-based resin may be, for example, a copolymer of vinyl acetate and another monomer copolymerizable therewith, in addition to polyvinyl acetate which is a vinyl acetate homopolymer. Examples of the other copolymerizable monomer include unsaturated carboxylic acids, olefins, vinyl ethers, and unsaturated sulfonic acids. The polymerization degree of the polyvinyl alcohol resin is usually about 1000 to 10000, preferably about 1500 to 5000.
These polyvinyl alcohol resins may be modified, and for example, polyvinyl formal, polyvinyl acetal, polyvinyl butyral, or the like modified with aldehydes may be used.
In the present invention, as a starting material for producing the polarizing film, an unstretched polyvinyl alcohol resin film (raw material film) having a thickness of 65 μm or less (for example, 60 μm or less), preferably 50 μm or less, more preferably 35 μm or less, and still more preferably 30 μm or less is used.
Thereby enabling to obtain a polarizing film of a film whose market demand is increasing. The width of the raw web film is not particularly limited, and may be, for example, about 400 to 6000 mm. The raw roll film is prepared, for example, as a roll (raw roll) of a long unstretched polyvinyl alcohol resin film.
The polyvinyl alcohol resin film used in the present invention may be laminated on a base film supporting the base film, that is, the polyvinyl alcohol resin film may be prepared as a laminated film formed of the base film and a polyvinyl alcohol resin film laminated thereon. In this case, the polyvinyl alcohol resin film can be produced by, for example, applying a coating liquid containing a polyvinyl alcohol resin to at least one surface of a base film and then drying the coating liquid.
As the substrate film, for example, a film containing a thermoplastic resin can be used. Specifically, the film is composed of a light-transmitting thermoplastic resin, preferably an optically transparent thermoplastic resin, and examples thereof include polyolefin resins such as chain polyolefin resins (polypropylene resins and the like) and cyclic polyolefin resins (norbornene resins and the like); cellulose resins such as triacetyl cellulose and diacetyl cellulose; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; a polycarbonate-based resin; (meth) acrylic resins such as methyl methacrylate resins; a polystyrene-based resin; a polyvinyl chloride resin; acrylonitrile-butadiene-styrene resins; acrylonitrile-styrene resin; polyvinyl acetate resin; a polyvinylidene chloride resin; a polyamide resin; a polyacetal resin; modified polyphenylene ether resin; a polysulfone-based resin; a polyether sulfone-based resin; a polyarylate-based resin; a polyamide imide resin; polyimide resins, and the like.
The polarizing film can be continuously manufactured as a long polarizing film by performing a drying process after performing a specific treatment process of continuously conveying the long raw material film along a film conveying path of a polarizing film manufacturing apparatus while winding the long raw material film from a raw material roll, immersing the long raw material film in a treatment liquid (hereinafter, also referred to as a "treatment bath") contained in a treatment tank, and then taking out the long raw material film. The treatment step is not limited to a method of immersing the film in the treatment bath as long as the treatment is performed by bringing the treatment liquid into contact with the film, and may be a method of treating the film by allowing the treatment liquid to adhere to the surface of the film by spraying, flowing down, dropping, or the like. When the treatment step is performed by immersing the film in the treatment bath, the treatment bath for performing one treatment step is not limited to one treatment bath, and the film may be sequentially immersed in two or more treatment baths to complete one treatment step.
Examples of the treatment liquid include a swelling liquid, a dyeing liquid, a crosslinking liquid, and a cleaning liquid. Further, as the treatment steps, there can be exemplified: a swelling step of swelling the raw web film by bringing the swelling solution into contact with the raw web film; a dyeing step of performing a dyeing treatment by bringing a dyeing liquid into contact with the swollen membrane; a crosslinking step of bringing the dyed film into contact with a crosslinking solution to perform crosslinking treatment; and a cleaning step of performing a cleaning treatment by bringing a cleaning liquid into contact with the crosslinked film. The uniaxial stretching treatment may be performed in a wet or dry manner between the series of treatment steps (i.e., before or after any one or more treatment steps and/or during any one or more treatment steps). Other treatment steps may be added as necessary.
In the present invention, an electromagnetic wave irradiation step of irradiating the film with an electromagnetic wave including infrared rays is performed after the crosslinking treatment. Further, after the electromagnetic wave irradiation step, the film was exposed to an absolute humidity of 80g/m3And a high humidity treatment step in the above atmosphere. By having the above two steps, the optical properties of the obtained polarizing film can be further improved, and the shrinkage force can be further suppressed. Since the shrinkage force can be suppressed, a polarizing film having excellent durability can be obtained.
An example of the method for producing the polarizing film of the present invention will be described in detail below with reference to fig. 1. Fig. 1 is a cross-sectional view schematically showing an example of the polarizing film manufacturing method and the polarizing film manufacturing apparatus used in the polarizing film manufacturing method of the present invention. The polarizing film manufacturing apparatus shown in fig. 1 exhibits the following configuration: the raw (unstretched) film 10 containing the polyvinyl alcohol resin is continuously wound from a raw roll 11 and conveyed along a film conveying path, and passes through a high-humidity treatment section 21 where high-humidity treatment is performed, sequentially through a swelling bath (swelling solution contained in a swelling tank) 13, a dyeing bath (dyeing solution contained in a dyeing tank) 15, a 1 st crosslinking bath (1 st crosslinking solution contained in a crosslinking tank) 17a, a 2 nd crosslinking bath (2 nd crosslinking solution contained in a crosslinking tank) 17b, and a cleaning bath (cleaning solution contained in a cleaning tank) 19 provided in the film conveying path. In order to further adjust the moisture content of the film after passing through the high-humidity treatment section 21, the film may be passed through a drying furnace (not shown). The obtained polarizing film 23 can be transported to, for example, a subsequent polarizing plate production step (step of bonding a protective film to one or both surfaces of the polarizing film 23) as it is. The arrows in fig. 1 indicate the film conveyance direction.
In the description of fig. 1, "treatment bath" is a generic term including a swelling bath, a dyeing bath, a crosslinking bath, and a cleaning bath, "treatment solution" is a generic term including a swelling solution, a dyeing solution, a crosslinking solution, and a cleaning solution, and "treatment bath" is a generic term including a swelling bath, a dyeing bath, a crosslinking bath, and a cleaning bath. The swelling bath, dyeing bath, crosslinking bath, and washing bath constitute a swelling part, a dyeing part, a crosslinking part, and a washing part, respectively, in the manufacturing apparatus of the present invention.
The film transport path of the polarizing film manufacturing apparatus can be constructed by arranging guide rollers 30 to 48, 60, 61 or nip rollers 50 to 55 at appropriate positions in addition to the treatment bath, the guide rollers 30 to 48, 60, 61 can support the film to be transported or further change the transport direction of the film, and the nip rollers 50 to 55 can press and nip the film to be transported, and apply a driving force to the film or further change the transport direction of the film by the rotation thereof. The guide rolls and the nip rolls can be disposed before and after each treatment bath and in the treatment bath, whereby the film can be introduced into and immersed in the treatment bath and removed from the treatment bath (see fig. 1). For example, by providing 1 or more guide rollers in each treatment bath and conveying the film along these guide rollers, the film can be immersed in each treatment bath.
In the polarizing film production apparatus shown in fig. 1, nip rollers (nip rollers 50 to 54) are arranged before and after each treatment bath, and thus, it is possible to perform roll-to-roll stretching in which longitudinal uniaxial stretching is performed by applying a circumferential speed difference between the nip rollers arranged before and after any 1 or more treatment baths.
In the polarizing film production apparatus shown in fig. 1, an electromagnetic wave irradiation unit 71 is disposed in the conveyance path downstream of the 2 nd crosslinking bath 17b and upstream of the cleaning bath 19, and an electromagnetic wave irradiation step is performed. Further, a high-humidity treatment section 21 is disposed on the conveyance path downstream of the cleaning bath 19, and a high-humidity treatment step is performed. Hereinafter, each step will be explained.
(swelling step)
The swelling step is performed for the purposes of removing foreign matters on the surface of the raw web film 10, removing a plasticizer in the raw web film 10, imparting dyeability, plasticizing the raw web film 10, and the like. The processing conditions are determined within a range that can achieve the object and that does not cause problems such as extreme dissolution and devitrification of the raw web film 10.
Referring to fig. 1, the swelling step may be performed by continuously unwinding the stock film 10 from the stock roll 11, conveying the same along the film conveying path, immersing the stock film 10 in the swelling bath 13 for a certain time, and then taking out the same. In the example of fig. 1, the raw web film 10 is conveyed along the film conveying path constituted by the guide rollers 60 and 61 and the nip roller 50 during the period from the winding of the raw web film 10 to the immersion in the swelling bath 13. In the swelling treatment, the film is conveyed along a film conveying path formed by the guide rollers 30 to 32 and the nip roller 51.
As the swelling liquid in the swelling bath 13, an aqueous solution in which boric acid (JP-A-10-153709), a chloride (JP-A-06-281816), an inorganic acid, an inorganic salt, a water-soluble organic solvent, an alcohol, or the like is added in an amount of about 0.01 to 10 wt% may be used in addition to pure water.
The temperature of the swelling bath 13 is, for example, about 10 to 50 ℃, preferably about 10 to 40 ℃, and more preferably about 15 to 30 ℃. The dipping time of the raw web film 10 is preferably about 10 to 300 seconds, and more preferably about 20 to 200 seconds. When the raw roll film 10 is a polyvinyl alcohol resin film stretched in advance in a gas, the temperature of the swelling bath 13 is, for example, about 20 to 70 ℃, preferably about 30 to 60 ℃. The dipping time of the raw web film 10 is preferably about 30 to 300 seconds, and more preferably about 60 to 240 seconds.
In the swelling treatment, the raw web film 10 is likely to swell in the width direction, and the film is likely to wrinkle. As one means for removing the wrinkles and conveying the film, there are: the guide rolls 30, 31 and/or 32 use rolls having a spreading function such as spreader rolls, helical rolls, nip rolls, or other spreading means such as a cloth guide, a bent roll (bent bar), a tenter frame. Another means for suppressing the occurrence of wrinkles is to perform a stretching process. For example, the uniaxial stretching treatment may be performed in the swelling bath 13 by utilizing the difference in peripheral speed between the nip roll 50 and the nip roll 51.
In the swelling treatment, since the film is swollen and expanded along the film transport direction, it is preferable to adopt means such as controlling the speeds of the nip rollers 50 and 51 arranged before and after the swelling bath 13 in order to eliminate the slack of the film in the transport direction without actively stretching the film. In addition, in order to stabilize the transport of the film in the swelling bath 13, it is also useful to Control the water flow in the swelling bath 13 by spraying water, or to use an EPC device (Edge Position Control device: a device for detecting the end of the film to prevent the film from being bent) in combination, or the like.
In the example shown in fig. 1, the film taken out of the swelling bath 13 is introduced into the dyeing bath 15 through the guide roll 32, the nip roll 51, and the guide roll 33 in this order.
(dyeing step)
The dyeing step is performed for the purpose of adsorbing and orienting the dichroic dye to the polyvinyl alcohol resin film after the swelling treatment. The treatment conditions are determined within a range that can achieve the object and that does not cause extreme problems such as dissolution and devitrification of the film. Referring to fig. 1, the dyeing step may be performed by conveying the film along a film conveying path constructed by nip rollers 51, guide rollers 33 to 36, and nip rollers 52, immersing the swollen film in a dyeing bath 15 (a treatment liquid stored in a dyeing bath) for a certain period of time, and then taking out the swollen film. In order to improve the dyeability of the dichroic dye, the film to be subjected to the dyeing step is preferably a film subjected to at least some uniaxial stretching treatment, or preferably subjected to the uniaxial stretching treatment at the time of dyeing treatment instead of or in addition to the uniaxial stretching treatment before the dyeing treatment.
When iodine is used as the dichroic dye, an aqueous solution having a concentration of iodine/potassium iodide/water of about 0.003 to 0.3/about 0.1 to 10/100 in terms of weight ratio can be used as the dyeing liquid in the dyeing bath 15. Instead of potassium iodide, other iodides such as zinc iodide may be used, or potassium iodide and other iodides may be used in combination. Further, a compound other than the iodide, for example, boric acid, zinc chloride, cobalt chloride, or the like may be coexistent. When boric acid is added, iodine is included, which is different from the crosslinking treatment described later, and if the aqueous solution contains about 0.003 parts by weight or more of iodine per 100 parts by weight of water, it can be regarded as the dyeing bath 15. The temperature of the dyeing bath 15 for dipping the film is usually about 10 to 45 ℃, preferably 10 to 40 ℃, and more preferably 20 to 35 ℃, and the dipping time of the film is usually about 30 to 600 seconds, preferably 60 to 300 seconds.
When a water-soluble dichroic dye is used as the dichroic dye, an aqueous solution having a concentration of dichroic dye/water of about 0.001 to 0.1/100 by weight ratio may be used as the dyeing liquid in the dyeing bath 15. The dyeing bath 15 may contain a dyeing assistant and the like, and may contain, for example, an inorganic salt such as sodium sulfate, a surfactant and the like. The dichroic dye may be used alone in 1 kind, or two or more kinds may be used in combination. The temperature of the dyeing bath 15 for dipping the film is, for example, about 20 to 80 ℃, preferably about 30 to 70 ℃, and the dipping time of the film is usually about 30 to 600 seconds, preferably about 60 to 300 seconds.
As described above, in the dyeing step, the uniaxial stretching of the film may be performed in the dyeing bath 15. The uniaxial stretching of the film can be performed by a method such as applying a circumferential speed difference between the nip roller 51 and the nip roller 52 arranged before and after the dyeing bath 15.
In the dyeing treatment, in order to convey the polyvinyl alcohol-based resin film while removing the film wrinkles, the guide rollers 33, 34, 35, and/or 36 may use a roller having a spreading function such as a spreader roller, a spiral roller, or a nip roller, or may use another spreading device such as a cloth guide, a bending roller, or a die holder, as in the swelling treatment. Another means for suppressing the occurrence of wrinkles is to perform stretching treatment, as in the swelling treatment.
In the example shown in fig. 1, the film taken out of the dyeing bath 15 is introduced into the crosslinking bath 17 through the guide roll 36, the nip roll 52, and the guide roll 37 in this order.
(crosslinking step)
The crosslinking step is a treatment for the purpose of imparting hydration resistance, adjusting the color (preventing the film from bluing, etc.), and the like by crosslinking. In the example shown in fig. 1, two crosslinking baths are arranged as the crosslinking baths for performing the crosslinking step, the 1 st crosslinking step for the purpose of water resistance is performed in the 1 st crosslinking bath 17a, and the 2 nd crosslinking step for the purpose of color hue adjustment is performed in the 2 nd crosslinking bath 17 b. Referring to fig. 1, the 1 st crosslinking step can be performed by conveying the film along a film conveying path constructed by nip rollers 52, guide rollers 37 to 40, and nip rollers 53a, immersing the dyed film in the 1 st crosslinking bath 17a (the 1 st crosslinking liquid stored in the crosslinking tank) for a certain period of time, and then taking out the film. The 2 nd crosslinking step can be carried out by conveying the film along a film conveying path constructed by the nip rollers 53a, the guide rollers 41 to 44, and the nip rollers 53b, immersing the film after the 1 st crosslinking step in the 2 nd crosslinking bath 17b (the 2 nd crosslinking liquid stored in the crosslinking tank) for a certain period of time, and then taking out the film. Hereinafter, the first crosslinking bath 17a and the second crosslinking bath 17b are both included when they are referred to as crosslinking baths, and the first crosslinking liquid 1 and the second crosslinking liquid 2 are both included when they are referred to as crosslinking liquids.
As the crosslinking liquid, a solution obtained by dissolving a crosslinking agent in a solvent can be used. Examples of the crosslinking agent include boron compounds such as boric acid and borax; glyoxal, glutaraldehyde, and the like. One kind of them may be used, or two or more kinds may be used in combination. As the solvent, for example, water may be used, and an organic solvent having compatibility with water may be further contained. The concentration of the crosslinking agent in the crosslinking solution is not limited to this, but is preferably in the range of 1 to 20% by weight, more preferably 6 to 15% by weight.
As the crosslinking liquid, an aqueous solution containing, for example, about 1 to 10 parts by weight of boric acid per 100 parts by weight of water can be used. When the dichroic dye used in the dyeing treatment is iodine, the crosslinking liquid preferably contains an iodide in addition to boric acid, and the amount thereof may be, for example, 1 to 30 parts by weight relative to 100 parts by weight of water. Examples of the iodide include potassium iodide and zinc iodide. In addition, compounds other than iodide, for example, zinc chloride, cobalt chloride, zirconium chloride, sodium thiosulfate, potassium sulfite, sodium sulfate, and the like may be coexistent.
In the crosslinking treatment, the concentrations of boric acid and iodide and the temperature of the crosslinking bath 17 may be appropriately changed according to the purpose. For example, in the case of the 1 st crosslinking liquid whose purpose is to achieve hydration resistance by crosslinking, the crosslinking treatment may be an aqueous solution having a concentration of boric acid/iodide/water of 3 to 10/1 to 20/100 by weight ratio. If necessary, other crosslinking agents may be used instead of boric acid, or boric acid and other crosslinking agents may be used in combination. The temperature of the first crosslinking bath 17a for dipping the film is usually about 50 to 70 ℃, preferably 53 to 65 ℃, and the dipping time of the film is usually about 10 to 600 seconds, preferably 20 to 300 seconds, more preferably 20 to 200 seconds. When the polyvinyl alcohol resin film stretched in advance before the swelling treatment is subjected to the dyeing treatment and the 1 st crosslinking treatment in this order, the temperature of the 1 st crosslinking bath 17a is usually about 50 to 85 ℃, preferably 55 to 80 ℃.
In the 2 nd crosslinked liquid for adjusting the hue, for example, when iodine is used as the dichroic dye, the concentration may be 1 to 5/3 to 30/100 in terms of the weight ratio boric acid/iodide/water. The temperature of the 2 nd crosslinking bath 17b for immersing the film is usually about 10 to 45 ℃, and the immersing time of the film is usually about 1 to 300 seconds, preferably 2 to 100 seconds.
The crosslinking treatment may be carried out a plurality of times, and is usually carried out 2 to 5 times. The composition and temperature of each crosslinking bath used in this case may be the same or different as long as they are within the above-mentioned ranges. The crosslinking treatment for imparting hydration resistance by crosslinking and the crosslinking treatment for adjusting the hue may be performed in a plurality of steps.
The uniaxial stretching treatment can be performed in the 1 st crosslinking bath 17a by the difference in the peripheral speed between the nip roll 52 and the nip roll 53 a. Further, the uniaxial stretching treatment can be performed in the 2 nd crosslinking bath 17b by the difference in the peripheral speed between the nip roller 53a and the nip roller 53 b.
In the crosslinking treatment, in order to convey the polyvinyl alcohol-based resin film while removing the wrinkles of the film, the guide rollers 38, 39, 40, 41, 42, 43, and/or 44 may use a roll having a spreading function such as a spreader roller, a helical roll, and a roll, or may use another spreading device such as a cloth guide, a bending roll, and a die holder, as in the swelling treatment. Another means for suppressing the occurrence of wrinkles is to perform stretching treatment, as in the swelling treatment.
In the example shown in FIG. 1, the film taken out of the 2 nd crosslinking bath 17b is introduced into the cleaning bath 19 through the guide roll 44 and the nip roll 53b in this order.
(cleaning Process)
The example shown in fig. 1 includes a cleaning step after the crosslinking step. The washing treatment is performed to remove excess chemical agents such as boric acid and iodine attached to the polyvinyl alcohol resin film. The cleaning step is performed by, for example, immersing the crosslinked polyvinyl alcohol resin film in the cleaning bath 19. The cleaning step may be performed as follows: instead of immersing the film in the cleaning bath 19, the cleaning solution may be sprayed onto the film or immersion in the cleaning bath 19 may be used in combination with spraying of the cleaning solution.
Fig. 1 shows an example of the cleaning treatment performed by immersing the polyvinyl alcohol resin film in the cleaning bath 19. The temperature of the cleaning bath 19 in the cleaning treatment is usually about 2 to 40 ℃, and the immersion time of the film is usually about 2 to 120 seconds.
In the cleaning process, in order to convey the polyvinyl alcohol resin film while removing wrinkles, rolls having a spreading function such as spreading rolls, spiral rolls, and nip rolls, or other spreading devices such as cloth guides, bending rolls, and tenter jigs may be used as the guide rolls 45, 46, 47, and/or 48. In the film cleaning process, a stretching process may be performed to suppress the occurrence of wrinkles.
(high humidity treatment Process)
In the example shown in fig. 1, the high-humidity treatment section 21 is provided after the cleaning bath 19, and the film is passed through the high-humidity treatment section 21, whereby the film is subjected to high-humidity treatment in which the film is exposed to a high-humidity atmosphere.
By performing a high humidity treatment in which the film is exposed to a high humidity atmosphere, the shrinkage force of the film can be suppressed. From the viewpoint of suppressing the shrinkage force of the film, the absolute humidity in the high-humidity treated section 21 was 80g/cm3Above, preferably 100g/cm3Above, further preferably 120g/cm3The above. Further, if the absolute humidity is excessively high, there is a possibility that dew condensation in the high-humidity treated portion or contamination of the film by dew condensation water may occur, and therefore, the absolute humidity is preferably 550g/m3Below, more preferably 400g/m3The following, more preferably 300g/m3Below, particularly preferably 180g/m3The following. By suppressing the shrinkage force, a polarizing film having excellent durability can be obtained.
The atmospheric temperature in the high-humidity treatment section 21 is preferably 40 ℃ or higher, more preferably 55 ℃ or higher, and still more preferably 60 ℃ or higher, from the viewpoint of easy adjustment of the absolute humidity to the above-described preferred value range and from the viewpoint of good film conveyance property. The temperature of the atmosphere is preferably 100 ℃ or lower, and from the viewpoint of obtaining excellent optical characteristics, it is preferably 90 ℃ or lower.
Exposing the film to an absolute humidity of 80g/cm3The high humidity treatment in the high humidity atmosphere is preferably 5 seconds or more, more preferably 10 seconds or more. The time varies depending on the temperature, but if the time is too long, the optical characteristics may deteriorate, and is preferably 60 minutes or less, more preferably 30 minutes or less, further preferably 10 minutes or less, and particularly preferably 5 minutes or less.
The high-humidity treatment step is preferably performed after the cleaning step, but the high-humidity treatment may be performed simultaneously with the cleaning treatment by spraying a cleaning liquid in the high-humidity treatment step, or the high-humidity treatment may be performed as the cleaning treatment in a case where the film is substantially cleaned by exposure to a high-humidity atmosphere.
The high-humidity treatment step may be performed as a treatment for drying the polyvinyl alcohol resin film, that is, a treatment for reducing the water content. Thus, when the moisture content can be appropriately adjusted, it is not necessary to separately perform the drying process before and after the high-humidity treatment step.
The moisture content of the film subjected to the high-humidity treatment step depends on the thickness of the film, but is usually about 13 to 50 wt%, preferably 30 to 50 wt%. The degree of decrease in the moisture content due to the high-humidity treatment step, i.e., the difference between the moisture content before the high-humidity treatment and the moisture content after the high-humidity treatment (moisture content difference Δ S), depends on the thickness of the film, and is, for example, 5 to 45% by weight, preferably 8 to 35% by weight. For example, when the thickness of the raw web film is about 40 μm or less, the moisture content difference Δ S may be less than 15 wt%.
The moisture content of the film after the high-humidity treatment step (polarizing film in the case where the high-humidity treatment step is the final step) depends on the thickness of the film, but is preferably 5 to 30% by weight, and more preferably 6 to 15% by weight from the viewpoint of the transportability of the film after the high-humidity treatment step. If the moisture content is too low, the film is likely to be cracked during transportation, and if the moisture content is too high, the film ends are likely to be curled due to dehumidification.
In general, the thinner the film, the more easily the moisture is dissipated, and therefore, the thinner the raw web film, the lower the moisture content after the high-humidity treatment step. If the moisture content is too low, the film conveyance property tends to be low.
The high-humidity treatment step may be performed immediately after the crosslinking step or the cleaning step, or may be performed after another step is performed after the crosslinking step or the cleaning step. As another step, a drying treatment may be mentioned. However, from the viewpoint of more effectively suppressing the increase in the shrinkage force, it is preferable to directly supply the film in the crosslinking step or the cleaning step to the high-humidity treatment step.
(stretching Process)
As described above, the raw web film 10 is subjected to the uniaxial stretching treatment by the wet or dry method between the above-described series of treatment steps (i.e., before and after any one or more treatment steps and/or during any one or more treatment steps). Specific examples of the uniaxial stretching treatment include inter-roll stretching in which 2 nip rolls constituting a film transport path (for example, 2 nip rolls arranged before and after a treatment bath) are subjected to longitudinal uniaxial stretching by applying a circumferential speed difference therebetween, hot-roll stretching as described in japanese patent No. 2731813, tenter stretching, and the like, and preferable is the inter-roll stretching. The uniaxial stretching step may be performed a plurality of times from the raw web film 10 to the polarizing film 23. As described above, the stretching treatment is also advantageous for suppressing the occurrence of wrinkles in the film.
The final cumulative stretching ratio of the polarizing film 23 based on the raw material film 10 is usually about 4.5 to 7 times, preferably 5 to 6.5 times. The stretching step may be performed in any treatment step, and in the case where the stretching treatment is performed in 2 or more treatment steps, the stretching treatment may be performed in any treatment step.
From the viewpoint of suppressing the shrinkage force of the film, the stretching step preferably includes a 1 st stretching step of performing uniaxial stretching treatment until the end of the cleaning step, and a 2 nd stretching step of performing uniaxial stretching treatment in the high-humidity treatment step. By providing the 1 st stretching step and the 2 nd stretching step, the contraction force can be suppressed more than in the case where the same stretching magnification is achieved only by the 1 st stretching step.
The uniaxial stretching treatment in the 2 nd stretching step may be either dry stretching or wet stretching, but when stretching is performed in a high humidity atmosphere, dry stretching is usually used. The uniaxial stretching treatment by dry stretching may be inter-roll stretching, hot-roll stretching, tenter stretching, or the like in which longitudinal uniaxial stretching is performed by applying a circumferential speed difference between 2 nip rolls. The stretching ratio in the 2 nd stretching step is preferably 1.01 to 1.4 times, more preferably 1.04 to 1.2 times.
The tension applied to the film in the 2 nd stretching step is preferably 50 to 5000N/m from the viewpoint of more effectively suppressing an increase in the shrinking force. The film tension is more preferably 300 to 1500N/m from the viewpoint of suppressing the occurrence of wrinkles in the film.
(electromagnetic wave irradiation step)
In the apparatus shown in fig. 1, the film is taken out from the 2 nd crosslinking step 17b, and after passing through the nip roll 53b and before being immersed in the cleaning bath 19, the film is irradiated with electromagnetic waves (electromagnetic wave irradiation step). In the apparatus shown in fig. 1, electromagnetic waves are irradiated by an electromagnetic wave irradiation unit 71. The electromagnetic wave used in the electromagnetic wave irradiation step of the present invention is an electromagnetic wave containing infrared rays, and the ratio of the radiation energy of the infrared rays having a wavelength of more than 2 μm and not more than 4 μm is preferably not less than 25%, more preferably not less than 28%, and still more preferably not less than 35% of the total radiation energy of the electromagnetic wave. By irradiating the film with such an electromagnetic wave, the optical properties of the obtained polarizing film can be improved. The upper limit of the ratio of the radiant energy of infrared rays having a wavelength of more than 2 μm and not more than 4 μm for the electromagnetic wave used in the present invention is not particularly limited, but is, for example, not more than 80%. Electromagnetic waves having a wavelength of 0.75 μ n to 1000 μm are generally referred to as infrared rays.
The present invention is a method in which the high-humidity treatment step is performed or an electromagnetic wave irradiation step is performed before the high-humidity treatment step, and therefore, the shrinkage force of the polarizing film can be further suppressed and the optical characteristics can be further improved. The mechanism by which the shrinkage force of the polarizing film can be suppressed and the optical properties can be improved is not clear, but it is presumed that the molecular motion in the film is excited by the electromagnetic wave irradiation step, whereby the immobilization of the dichroic dye such as iodine in the film after the crosslinking treatment is promoted, and that the high humidity treatment in this state contributes to the suppression of the shrinkage force and the improvement of the optical properties.
Fig. 2 shows a radiation energy spectrum of each electromagnetic wave irradiator. Table 1 shows the ratio of the radiation energy of the electromagnetic wave in each wavelength region (represented by the range of wavelength x μm) to the total radiation energy for each electromagnetic wave irradiator. The electromagnetic wave irradiators shown in fig. 2 and table 1 were a halogen heater (heat source temperature 2600 ℃ c.), a short wavelength infrared heater (heat source temperature 2200 ℃ c.), a high-speed response medium wavelength infrared heater (heat source temperature 1600 ℃ c.), a carbon heater (heat source temperature 1200 ℃ c.), a carbon heater (heat source temperature 950 ℃ c.), and a medium wavelength infrared heater (heat source temperature 900 ℃ c.).
[ Table 1]
In the electromagnetic wave irradiation unit 71 of the present invention, it is preferable to irradiate an electromagnetic wave having an infrared ray whose wavelength exceeds 2 μm and is 4 μm or less in which the ratio of the irradiation energy to the total irradiation energy is 25% or more, from the viewpoint of further suppressing the shrinkage force and further improving the optical characteristics. As shown in Table 1, the ratio of the radiation energy of the infrared ray having a wavelength of more than 2 μm and not more than 4 μm in the short wavelength infrared ray heater (heat source temperature of 2200 ℃), the high-speed response medium wavelength infrared ray heater (heat source temperature of 1600 ℃), the carbon heater (heat source temperature of 1200 ℃), the carbon heater (heat source temperature of 950 ℃), and the medium wavelength infrared ray heater (heat source temperature of 900 ℃) was not less than 25% of the total radiation energy.
The electromagnetic wave irradiation unit 71 may be constituted by 1 electromagnetic wave irradiator or a plurality of electromagnetic wave irradiators. When the electromagnetic wave irradiators are configured by a plurality of electromagnetic wave irradiators, it is preferable to select the plurality of electromagnetic wave irradiators so that the radiation energy of infrared rays having a wavelength of more than 2 μm and not more than 4 μm emitted from the plurality of electromagnetic wave irradiators reaches 25% or more of the total radiation energy of electromagnetic waves emitted from the plurality of electromagnetic wave irradiators. In fig. 1, the electromagnetic wave irradiation unit 71 is configured to irradiate only one surface of the film with electromagnetic waves, and a plurality of electromagnetic wave irradiators may be arranged so that both surfaces of the film are irradiated with electromagnetic waves. The electromagnetic wave irradiation section 71 is preferably configured such that the entire region of the polyvinyl alcohol resin film to be irradiated in the width direction is irradiated with electromagnetic waves.
In the electromagnetic wave irradiation step, the electromagnetic wave is preferably irradiated from the upper side in the direction perpendicular to the film surface. The distance between the electromagnetic wave radiation port of the electromagnetic wave radiation device and the film in the electromagnetic wave radiation section 71 is preferably 2 to 40cm, and more preferably 5 to 20 cm. Among them, it is preferable to irradiate while appropriately selecting the distance in consideration of the radiation energy of the electromagnetic wave radiated from the electromagnetic wave irradiator, the temperature of the film surface, and the like. The temperature of the film surface when irradiated with electromagnetic waves is preferably maintained at 30 to 90 ℃, more preferably 40 to 80 ℃.
In the electromagnetic wave irradiation step, the heat quantity of irradiation of electromagnetic waves per unit volume of the film is usually set to 100J/cm3Above, can be set to 50kJ/cm3The following. From the viewpoint of improving the optical characteristics of the polarizing film, 100J/cm is preferable3Above, more preferably 500J/cm3More preferably 1000J/cm or more3The above. In addition, from the viewpoint of suppressing deterioration of the film due to temperature rise, the heat quantity of irradiation of electromagnetic waves per unit volume of the film is preferably 10kJ/cm3Less than, more preferably 5000J/cm3The lower limit is more preferably 3000J/cm3The following. In general, the moisture content of the film is reduced in proportion to the amount of heat of irradiation with electromagnetic waves, but the electromagnetic wave irradiation step of the present invention is not intended to reduce the moisture content of the film, and therefore the amount of heat of irradiation can be appropriately selected, and is preferably appropriately selected within the above range。
The electromagnetic wave irradiation step may be performed on the film immersed in at least one crosslinking bath, and is not limited to the film immersed in all crosslinking baths as shown in fig. 1. That is, in the example shown in fig. 1, the electromagnetic wave irradiation step may be performed on the film after immersion in the 1 st crosslinking bath and before immersion in the 2 nd crosslinking bath, or the electromagnetic wave irradiation step may be performed on the film after immersion in the 2 nd crosslinking bath. Among these, the step of irradiating with electromagnetic waves is preferable because boric acid incorporated into the film by immersion in the crosslinking bath can be crosslinked, and therefore, the step of irradiating with electromagnetic waves to the film immersed in all the crosslinking baths can crosslink boric acid more efficiently. The electromagnetic wave irradiation step may be performed after the crosslinking step and before the high-humidity treatment step, and may be performed before or after the cleaning step.
The irradiation with electromagnetic waves is preferably performed within 10 seconds, more preferably within 5 seconds, after the film is taken out from the crosslinking bath. The shorter the time from the removal from the crosslinking bath to the irradiation with the electromagnetic wave, the more the optical properties of the polarizing film can be further improved by the irradiation with the electromagnetic wave. In the electromagnetic wave irradiation step, it is preferable that the amount of water molecules adhering to the film surface is small. This is because: if water molecules exist on the surface of the film, the effect of exciting molecular motion in the film by electromagnetic wave irradiation is reduced because the water molecules on the surface of the film absorb infrared rays. Since the crosslinking liquid adheres to the surface of the film immediately after the film is taken out from the crosslinking bath, it is preferable to provide a liquid removing mechanism for removing the crosslinking liquid before the electromagnetic wave irradiation step. In fig. 1, the nip roller 53b also functions as a liquid removing mechanism for removing the crosslinking liquid adhering to the film surface. As the liquid removing mechanism, a mechanism for removing liquid by blowing air to the film, a blade for removing liquid by contacting with the film, or the like can be used in addition to the nip roller.
From the viewpoint of economy, if the film processing speed is set to a high speed, specifically, if the processing speed is set to a processing speed as high as 10 to 100 m/min, the electromagnetic wave irradiation time becomes short, and the irradiation heat amount may be insufficient. In order to cope with this, a plurality of electromagnetic wave irradiators are provided in parallel, whereby sufficient irradiation heat can be obtained.
(drying Process)
The treatment of drying the polyvinyl alcohol resin film may be performed after the washing step and before or after the high-humidity treatment step. The method of drying the film is not particularly limited.
For example, a drying oven equipped with a hot air dryer may be used. The drying temperature is, for example, about 30 to 100 ℃, and the drying time is, for example, about 30 to 600 seconds. The treatment of drying the polyvinyl alcohol resin film may be performed using a far infrared heater. The thickness of the polarizing film 23 obtained in the above manner is, for example, about 5 to 30 μm.
In consideration of the balance with the visibility correction polarization degree Py, the visibility correction monomer transmittance Ty of the obtained polarizing film is preferably 40 to 47%, more preferably 41 to 45%. The visibility correction polarization degree Py is preferably 99.9% or more, more preferably 99.95% or more, and the larger the value, the more preferable. The greater the visibility-correcting monomer transmittance Ty of the polarizing film, the greater the effect of improving the optical characteristics obtained by the present invention. Therefore, the present invention is particularly advantageous in the case of manufacturing a polarizing film having a visibility correcting monomer transmittance Ty of 41% or more, further 42% or more, further 43.5% or more. According to the present invention, for example, a polarizing film having a Ty of 43.5% or more and a Py of 99.994% or more can be obtained. Ty and Py were measured as described in the examples section below.
The obtained polarizing film may be wound around a winding roll in sequence to be in a roll form, or may be directly subjected to a polarizing plate production step (a step of laminating a protective film or the like on one or both surfaces of the polarizing film) without being wound.
(other treatment Process for polyvinyl alcohol resin film)
Processes other than the above-described process may also be applied. Examples of processing that may be appended include: the treatment (color correction treatment) of dipping in an aqueous iodide solution not containing boric acid, or the treatment (zinc treatment) of dipping in an aqueous solution not containing boric acid but containing zinc chloride or the like, is performed after the crosslinking step.
< polarizing plate >
A polarizing plate can be obtained by bonding a protective film to at least one surface of the polarizing film produced as described above via an adhesive. Examples of the protective film include films containing acetyl cellulose resins such as triacetyl cellulose and diacetyl cellulose; films comprising polyester resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate; polycarbonate resin films and cycloolefin resin films; an acrylic resin film; a film of a chain olefin resin containing a polypropylene resin.
In order to improve the adhesiveness between the polarizing film and the protective film, the surface of the polarizing film and/or the protective film to be bonded may be subjected to surface treatment such as corona treatment, flame treatment, plasma treatment, ultraviolet irradiation, primer coating treatment, saponification treatment, or the like. Examples of the adhesive used for bonding the polarizing film and the protective film include: an active energy ray-curable adhesive such as an ultraviolet ray-curable adhesive; an aqueous adhesive such as an aqueous solution of a polyvinyl alcohol resin, an aqueous solution containing a crosslinking agent, and a urethane emulsion adhesive. The ultraviolet-curable adhesive may be a mixture of an acrylic compound and a photo radical polymerization initiator, a mixture of an epoxy compound and a photo cation polymerization initiator, or the like. Further, a cationically polymerizable epoxy compound may be used in combination with a radically polymerizable acrylic compound, and a photo cationic polymerization initiator and a photo radical polymerization initiator may be used in combination as initiators.
Examples
The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.
< example 1>
The polarizing film of example 1 was produced from a polyvinyl alcohol resin film using the production apparatus shown in fig. 1. Specifically, a long polyvinyl alcohol (PVA) raw roll film (KURARAY co., trade name "KURARAY vinyl VF-PE # 6000", manufactured by LTD) having a thickness of 60 μm was continuously conveyed while being rolled out from the roll, and was immersed in a swelling bath containing pure water at 30 ℃ for a retention time of 89 seconds (swelling step). Then, the film taken out of the swelling bath was immersed in a dyeing bath at 30 ℃ containing iodine at a retention time of 156 seconds with a potassium iodide/boric acid/water ratio of 2/0.3/100 (weight ratio) (dyeing step). Subsequently, the film taken out of the dyeing bath was immersed in a first crosslinking bath at 56 ℃ with a residence time of 67 seconds at 12/4/100 (weight ratio) of potassium iodide/boric acid/water, and then immersed in a second crosslinking bath at 40 ℃ with a residence time of 11 seconds at 9/3/100 (weight ratio) of potassium iodide/boric acid/water (crosslinking step). In the dyeing step and the crosslinking step, longitudinal uniaxial stretching is performed by roll-to-roll stretching in a bath. The total stretching ratio based on the raw web film was set to 5.69 times.
Next, an electromagnetic wave irradiator (Medium-wavelength infrared heater (MW heater) product name: gold 8 Medium-wave twist tube emitter, manufactured by Heraeus corporation, having a heat source temperature of 900 ℃ and a maximum energy density of 60kW/m was used for the film taken out of the 2 nd crosslinking bath 17b and passed through a nip roller 53b2) An electromagnetic wave radiation port was disposed at a position 5cm from the film surface, and electromagnetic waves were irradiated at an output of 30% with respect to the maximum irradiation output of the electromagnetic wave irradiator. The heat quantity of irradiation of electromagnetic waves per unit volume of the film was 560J/cm3. Further, the irradiation heat amount of the electromagnetic wave per unit volume of the film is calculated by the following equation.
(irradiation heat quantity of electromagnetic wave per unit volume of membrane) { (maximum energy density) × (heater heating portion surface area) × output power (%)/(electromagnetic wave irradiation area) } × (electromagnetic wave irradiation time)/(membrane thickness)
The output power (%) represents a ratio (%) of the output power of the actual irradiation to the maximum irradiation output power of the electromagnetic wave irradiator.
After being taken out from the 2 nd crosslinking bath 17b, the time required for the film to reach the irradiation position of the electromagnetic wave irradiator after being carried and to be irradiated with the electromagnetic wave was 5 seconds.
Making film irradiated with electromagnetic wave at 5 deg.CThe cleaning bath 19 containing pure water was immersed for a retention time of 3 seconds (cleaning step). Then, the temperature and the absolute humidity in the high humidity treatment section 21 were set to 75 ℃ and 147g/cm3And a relative humidity of 61%, and the film was exposed to a high-humidity environment with a retention time of 60 seconds. At this time, uniaxial stretching treatment was performed 1.14 times in total. Finally, the mixture was dried in a drying oven at a temperature of 30 ℃ and a concentration of 10g/cm3And a drying step of drying the film with a residence time of 120 seconds to obtain a polarizing film. The thickness of the obtained polarizing film was 23 μm.
< examples 2 to 3>
In the electromagnetic wave irradiation step, a polarizing film was obtained in the same manner as in example 1, except that the output (%) of the electromagnetic wave irradiator and the amount of heat of electromagnetic wave irradiation per unit volume of the film were as shown in table 2. The thickness of the obtained polarizing film was 23 μm.
< comparative example 1>
A polarizing film was obtained in the same manner as in example 1, except that the electromagnetic wave irradiation step was not performed.
The thickness of the obtained polarizing film was 23 μm.
< comparative example 2>
Polarizing films were obtained in the same manner as in example 1 except that the output (%) of the electromagnetic wave irradiator and the amount of heat of irradiation of electromagnetic waves per unit volume of the film in the electromagnetic wave irradiation step were set as shown in table 2, the high-humidity treatment step was not performed, and the temperature in the drying step was set as shown in table 2. The thickness of the obtained polarizing film was 23 μm.
< comparative example 3>
Polarizing films were obtained in the same manner as in example 1, except that the electromagnetic wave irradiation step and the high-humidity treatment step were not performed, the high-humidity treatment step was not performed, and the temperature in the drying step was set as shown in table 2. The thickness of the obtained polarizing film was 23 μm.
[ evaluation of polarizing film ]
(a) Measurement of monomer transmittance, degree of polarization and b-value of Cross color
The polarizing films obtained in the examples and comparative examples were measured for MD transmittance and TD transmittance in the wavelength range of 380 to 780nm using an integrating sphere-equipped spectrophotometer ("V7100" manufactured by japan spectrographs), and the monomer transmittance and the degree of polarization at each wavelength were calculated based on the following formulas.
Monomer transmittance (%) - (MD + TD)/2
Degree of polarization (%) { (MD-TD)/(MD + TD) } × 100
"MD transmittance" means: the transmittance when the direction of the polarized light from the Gelanthompson prism is parallel to the transmission axis of the polarizing film sample is represented by "MD" in the above formula. In addition, "TD transmittance" means: the transmittance when the direction of the polarized light from the Gelanotumpson prism is orthogonal to the transmission axis of the polarizing film sample is represented by "TD" in the above formula. Regarding the resulting monomer transmittance and degree of polarization, the transmittance was measured by JIS Z8701: 1999 "color expression method-XYZ color system and X10Y10Z10Visibility correction was performed in a 2-degree field of view (C light source) of the color system "to obtain the visibility correction cell transmittance (Ty), visibility correction polarization (Py), and b-value of the cross hue. Table 2 shows the calculation results.
(b) Measurement of contractile force
From the polarizing films obtained in the examples and comparative examples, measurement samples having a width of 2mm and a length of 10mm with the absorption axis direction (MD, stretching direction) as the long side were cut out. This sample was placed in a thermomechanical analyzer (TMA) "EXSTAR-6000" manufactured by SII Nano Technology inc, and a shrinkage force (MD shrinkage force) in the longitudinal direction (absorption axis direction, MD) generated when the sample was held at 80 ℃ for 4 hours was measured while keeping the dimension constant. The smaller the contractile force measured in this way, the more excellent the durability, so that it is more preferable, for example, 4N/2mm or less.
[ Table 2]
| Example 1 | Example 2 | Example 3 | Comparative example 1 | Comparative example 2 | Comparative example 3 | |
| PVA raw material thickness (mum) | 60 | 60 | 60 | 60 | 60 | 60 |
| Total draw ratio | 6.49 | 6.49 | 6.49 | 6.49 | 5.69 | 5.69 |
| Types of electromagnetic wave irradiators | MN | MW | MW | MW | ||
| Output Power (%) of |
30 | 50 | 70 | 70 | ||
| Electromagnetic radiation heat (J/cm3) | 560 | 920 | 1290 | 1290 | ||
| The ratio of the radiation energy of infrared rays having a wavelength of more than 2 μm and not more than 4 |
46％ | 46％ | 46％ | 46％ | ||
| Temperature (. degree. C.) in the high humidity treatment step | 75 | 75 | 75 | 75 | ||
| Relative humidity in the high humidity treatment step (%) | 61 | 61 | 61 | 61 | ||
| Absolute humidity (g/cm3) of high humidity treatment step | 147 | 147 | 147 | 147 | ||
| Stretching ratio in high humidity treatment step | 1.14 | 1.14 | 1.14 | 1.14 | ||
| Temperature (. degree.C.) in the drying |
30 | 30 | 30 | 30 | 80 | 80 |
| Visibility correction monomer transmittance Ty (%) | 43.59 | 43.67 | 43.69 | 43.63 | 43.4 | 43.25 |
| Visibility correction polarization degree Py (%) | 99.995 | 99.995 | 99.996 | 99.992 | 99.994 | 99.995 |
| Contractile force (N/2mm) | 3.9 | 3.98 | 3.9 | 3.99 | 3.97 | 3.97 |
| B value of orthorhombic color | -1.2 | -0.91 | -0.54 | -1.83 | -0.45 | -0.35 |
As shown in Table 2, the polarizing films of examples 1 to 3 have more excellent optical characteristics than those of comparative examples 1 to 3. As shown in table 2, the polarizing films of examples 1 to 3 can suppress the shrinkage force even more than those of comparative examples 2 and 3, though the total stretching ratio is higher.
Description of the symbols
10 comprises a raw material film of a polyvinyl alcohol resin, 11 raw material rolls, 13 swelling baths, 15 dyeing baths, 17a 1 st crosslinking bath, 17b 2 nd crosslinking bath, 19 cleaning baths, 21 high-humidity treatment sections, 23 polarizing films, 30 to 48, 60, 61 guide rolls, 50 to 52, 53a, 53b, 54, 55 nip rolls, and 71 electromagnetic wave irradiation sections.
Claims (6)
1. A method for producing a polarizing film from a polyvinyl alcohol resin film, the method comprising:
a dyeing step of dyeing the polyvinyl alcohol resin film with a dichroic dye;
a crosslinking step of crosslinking the polyvinyl alcohol resin film after the dyeing step with a crosslinking agent;
an electromagnetic wave irradiation step of irradiating the polyvinyl alcohol resin film after the crosslinking step with an electromagnetic wave containing infrared rays; and
a high humidity treatment step of exposing the polyvinyl alcohol resin film irradiated with the electromagnetic wave to an absolute humidity of 80g/m3In the above-mentioned atmosphere, the gas,
in the electromagnetic wave irradiation step, the ratio of the radiant energy of infrared rays having a wavelength of more than 2 μm and not more than 4 μm in the electromagnetic wave is not less than 25% of the total radiant energy,
a cleaning step of cleaning the polyvinyl alcohol resin film between the electromagnetic wave irradiation step and the high-humidity treatment step,
in the electromagnetic wave irradiation step, electromagnetic waves are irradiated by a short-wavelength infrared heater, a high-speed response medium-wavelength infrared heater, or a carbon heater.
2. The method for producing a polarizing film according to claim 1,
in the electromagnetic wave irradiation step, the amount of heat of irradiation with the electromagnetic wave is 100J/cm per unit volume of the polyvinyl alcohol resin film3Above and 50kJ/cm3The following.
3. The method for producing a polarizing film according to claim 1 or 2,
in the high-humidity treatment step, the polyvinyl alcohol resin film is uniaxially stretched 1.04 to 1.2 times.
4. The method for producing a polarizing film according to claim 1 or 2,
in the crosslinking step, the polyvinyl alcohol resin film after the dyeing step is immersed in a crosslinking liquid in which a crosslinking agent is dissolved in water,
removing the crosslinking liquid adhering to the surface of the polyvinyl alcohol resin film before the electromagnetic wave irradiation step.
5. A polarizing film manufacturing apparatus for manufacturing a polarizing film from a polyvinyl alcohol resin film, the polarizing film manufacturing apparatus comprising:
a dyeing section for dyeing the polyvinyl alcohol resin film with a dichroic dye;
a crosslinking section for crosslinking the dyed polyvinyl alcohol resin film with a crosslinking agent;
an electromagnetic wave irradiation unit that irradiates the polyvinyl alcohol resin film subjected to the crosslinking treatment with an electromagnetic wave containing infrared rays; and
a high-humidity treatment section for exposing the polyvinyl alcohol resin film irradiated with the electromagnetic wave to an absolute humidity of 80g/m3In the above-mentioned atmosphere, the gas,
the electromagnetic wave irradiation unit is an electromagnetic wave irradiation unit that irradiates an electromagnetic wave in which a ratio of radiant energy of infrared rays having a wavelength of more than 2 μm and not more than 4 μm is not less than 25% of total radiant energy,
the electromagnetic wave irradiation part is a short wavelength infrared heater, a high-speed response medium wavelength infrared heater or a carbon heater.
6. The polarizing film manufacturing apparatus according to claim 5,
in the crosslinking section, the dyed polyvinyl alcohol resin film is immersed in a crosslinking liquid that is a solution obtained by dissolving a crosslinking agent in water to perform crosslinking treatment,
a liquid removing mechanism for removing the crosslinking liquid adhering to the surface of the crosslinked polyvinyl alcohol resin film is provided in front of the electromagnetic wave irradiation unit, and the crosslinking liquid is removed by the liquid removing mechanism,
a cleaning section for cleaning the polyvinyl alcohol resin film is provided between the electromagnetic wave irradiation section and the high-humidity treatment section.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013228718A (en) * | 2012-03-30 | 2013-11-07 | Kuraray Co Ltd | Manufacturing method of polyvinyl alcohol-based polymer film |
| CN104094141A (en) * | 2012-01-23 | 2014-10-08 | 住友化学株式会社 | Polarizing film, method for manufacturing same, and polarizing plate |
| KR20150101510A (en) * | 2014-02-26 | 2015-09-04 | 동우 화인켐 주식회사 | Method of preparing polarizer |
| WO2016093278A1 (en) * | 2014-12-12 | 2016-06-16 | 住友化学株式会社 | Method for manufacturing polarizing film, and polarizing film |
| WO2016093277A1 (en) * | 2014-12-12 | 2016-06-16 | 住友化学株式会社 | Method for producing polarizing film, and polarizing film |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5994706A (en) * | 1982-11-22 | 1984-05-31 | Mitsui Toatsu Chem Inc | Manufacture of polarizing film |
| JP2005002176A (en) * | 2003-06-10 | 2005-01-06 | Asahi Denka Kogyo Kk | Film, method for producing the same, and polarizing plate using the film |
| JP4213616B2 (en) * | 2004-03-31 | 2009-01-21 | 大日本印刷株式会社 | Base film for liquid crystal panel, functional film for liquid crystal panel, method for producing functional film, and apparatus for producing functional film |
| US7573637B2 (en) * | 2004-08-03 | 2009-08-11 | Seiko Epson Corporation | Intrinsic polarizer and method of manufacturing an intrinsic polarizer |
| GB0520489D0 (en) * | 2005-10-07 | 2005-11-16 | Kontrakt Technology Ltd | Organic compound, optical crystal film and method of producing thereof |
| JP2008122502A (en) * | 2006-11-09 | 2008-05-29 | Sumitomo Chemical Co Ltd | Method of manufacturing polarizing plate |
| US8623476B2 (en) * | 2008-11-28 | 2014-01-07 | Fujifilm Corporation | Polarizing element and method of producing the same |
| JP2012123229A (en) * | 2010-12-09 | 2012-06-28 | Sumitomo Chemical Co Ltd | Manufacturing method of polarizing laminate film and polarizing plate |
| JP6371031B2 (en) * | 2012-07-02 | 2018-08-08 | 住友化学株式会社 | Polarizing plate manufacturing method and manufacturing apparatus |
| TWI537287B (en) | 2013-11-06 | 2016-06-11 | Chang Chun Petrochemical Co | Polyvinyl alcohol-based polymer film and method for producing the same |
| JPWO2015098491A1 (en) * | 2013-12-25 | 2017-03-23 | コニカミノルタ株式会社 | Cellulose ester film, method for producing the same, and polarizing plate |
| JP6460314B2 (en) * | 2014-11-13 | 2019-01-30 | 福田 英樹 | Umbrella ties and umbrella units |
-
2017
- 2017-08-11 KR KR1020170102173A patent/KR102512665B1/en active IP Right Grant
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- 2017-08-16 CN CN201710701567.5A patent/CN107765353A/en active Pending
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104094141A (en) * | 2012-01-23 | 2014-10-08 | 住友化学株式会社 | Polarizing film, method for manufacturing same, and polarizing plate |
| JP2013228718A (en) * | 2012-03-30 | 2013-11-07 | Kuraray Co Ltd | Manufacturing method of polyvinyl alcohol-based polymer film |
| KR20150101510A (en) * | 2014-02-26 | 2015-09-04 | 동우 화인켐 주식회사 | Method of preparing polarizer |
| WO2016093278A1 (en) * | 2014-12-12 | 2016-06-16 | 住友化学株式会社 | Method for manufacturing polarizing film, and polarizing film |
| WO2016093277A1 (en) * | 2014-12-12 | 2016-06-16 | 住友化学株式会社 | Method for producing polarizing film, and polarizing film |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2018032023A (en) | 2018-03-01 |
| TWI729190B (en) | 2021-06-01 |
| KR102512665B1 (en) | 2023-03-21 |
| TW201809760A (en) | 2018-03-16 |
| JP7123532B2 (en) | 2022-08-23 |
| CN107765353A (en) | 2018-03-06 |
| KR20180020894A (en) | 2018-02-28 |
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