WO2020241705A1

WO2020241705A1 - Laminate for circular polarization element transfer and method for manufacturing optical article using same

Info

Publication number: WO2020241705A1
Application number: PCT/JP2020/020960
Authority: WO
Inventors: 柴野　博史
Original assignee: 東洋紡株式会社
Priority date: 2019-05-28
Filing date: 2020-05-27
Publication date: 2020-12-03
Also published as: JPWO2020241705A1; CN113874765A; KR20220011678A

Abstract

Provided is a means for dealing with further thinned image processing devices. In this laminate for circular polarization element transfer, a polarizer and a λ/4 retardation layer are laminated in this order on a releasable film, or a λ/4 retardation layer and a polarizer are laminated in this order on the releasable film. It is possible to manufacture an image display device having a circular polarization element by transferring the laminate to a constituent member of the image display device.

Description

A laminate for transferring a circularly polarizing element and a method for manufacturing an optical article using the same

The present invention relates to a laminate for transferring a circularly polarized element, and an optical article using the same (for example, a transparent conductive base material having a circularly polarized element, a touch panel having a circularly polarized element, and a transparent group for a surface cover having a circularly polarized element. The present invention relates to a method for manufacturing a material (an image display device having a material and a circular polarization element).

In recent years, organic EL display devices have been attracting attention as image display devices in various fields. In particular, the organic EL display device is expected not only as a means for reducing the thickness and weight of a large image display device such as a television because of its thinness, but also as a curved image display device and a flexible image display device. Has been done.

In the organic EL display device, a circular polarizing plate is attached to the visible side of the organic EL cell in order to prevent reflection of wiring and cells. Conventionally, a circular polarizing plate has a structure in which a λ / 4 retardation film is bonded to the organic EL cell side of the polarizing plate. The polarizing plate is obtained by attaching a polarizing element protective film to a polarizing element. As the polarizer protective film, a rigid film having a thickness of 40 to 100 μm such as triacetyl cellulose (TAC), acrylic resin, cyclic polyolefin (COP), and polyethylene terephthalate (PET) is used. Further, as the λ / 4 retardation film, a film obtained by stretching a resin having birefringence such as cyclic polyolefin or polycarbonate, or a TAC provided with a liquid crystal compound layer by coating is used.

It is also possible to reduce the thickness of the circular polarizing plate by omitting the polarizer protective film on the λ / 4 retardation film side of the polarizing plate and directly adhering the λ / 4 retardation film to one side of the polarizer. However, there is a limit to the thinning by this method.

In the organic EL display device, a touch panel is combined (for example, Patent Documents 1 and 2), and in an in-vehicle or outdoor organic EL display device (for example, a car navigation system, a back monitor, a side monitor, an instrument panel, etc.), the surface cover is transparent. Since a base material is often provided and many members are provided, even if the organic EL display cell is made thinner, there is a limit to making the organic EL display device thinner.

JP-A-2017-84153 JP-A-2017-128004

The present invention has been made against the background of the problems of the prior art. That is, one object of the present invention is to provide a means for supporting a further thinned image display device.

The present inventor has completed the present invention as a result of diligent studies to achieve such an object. That is, the present invention includes the following aspects.
Item 1.
A circle in which the polarizer and the λ / 4 retardation layer are laminated in this order on the releasable film, or the λ / 4 retardation layer and the polarizer are laminated in this order on the releasable film. Laminated body for transfer of polarizing element.
Item 2.
A method for manufacturing a transparent conductive base material having a circular polarization element.
(A) The λ / 4 retardation layer of the laminated body for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a releasable film on a transparent conductive substrate, is transparent conductivity. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (B) the transparent conductive substrate has a λ / 4 retardation layer and a polarizer on the releasable film. A method comprising laminating the circularly polarizing element transfer laminate so that the polarizers of the circularly polarized element transfer laminates laminated in this order are arranged on the transparent conductive base material side.
Item 3.
A method for manufacturing a touch panel having a circularly polarized element.
(C) The λ / 4 retardation layer of a laminate for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a transparent conductive base material of a touch panel, is described above. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the transparent conductive base material side, or (D) λ / 4 phase difference on the releasable film on the transparent conductive base material of the touch panel. The step of laminating the circularly polarizing element transfer laminate is included so that the polarizer of the circular polarization element transfer laminate in which the layers and the polarizers are laminated in this order is arranged on the transparent conductive substrate side. ,Method.
Item 4.
A method for manufacturing an image display device having a circular polarization element.
A method comprising a step of providing the touch panel on an image display device so that a touch panel of a touch panel having a circular polarization element or a circular polarization element manufactured by the method of item 3 is arranged on the visual side.
Item 5.
A method for manufacturing a transparent base material for a surface cover having a circular polarization element.
(E) The λ / 4 retardation layer of the circularly polarizing element transfer laminate in which the polarizer and the λ / 4 retardation layer are laminated in this order on the transparent substrate for the surface cover on the releasable film is the transparent. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (F) the transparent substrate for the surface cover, the λ / 4 retardation layer and the polarizer on the releasable film. A method comprising laminating the circularly polarizing element transfer laminate so that the polarizer of the circularly polarized element transfer laminate laminated in this order is arranged on the transparent substrate side.
Item 6.
A method for manufacturing an image display device having a circular polarization element.
The step of providing the transparent base material in the image display device so that the transparent base material for the surface cover of the transparent base material for the surface cover having a circular polarization element manufactured by the method of Item 5 is arranged on the visual side. ,Method.

The present invention makes it possible to further reduce the thickness of the image display device.

In the laminated body for transferring a circularly polarizing element of the present invention, the polarizer and the λ / 4 retardation layer are laminated in this order on the releasable film, or the λ / 4 retardation layer and the λ / 4 retardation layer are laminated on the releasability film. It is preferable that the polarizers are laminated in this order.

The stacking order of the polarizer and the λ / 4 retardation layer can be selected, for example, depending on the position at which the transfer target is incorporated in the image display device. For example, in the case of the image display cell-λ / 4 retardation layer-polarizer-transfer target, the stacking order is preferably the release film-λ / 4 retardation layer-polarizer. In the order of display cell-transfer target-λ / 4 retardation layer-polarizer, the stacking order is preferably releasable film-polarizer-λ / 4 retardation layer.

(Releasable film)
As the releasable film of the laminate for transferring the circularly polarizing element, a releasable film widely used as a releasable film can be appropriately used. The releasable film consists of a single layer or multiple layers and includes at least a base film. The base film is preferably a resin film. The resin of the resin film is not particularly limited, and any resin film such as polyester, polycarbonate, polyamide, polyimide, polyamideimide, polystyrene, triacetyl cellulose, polypropylene, and cyclic polyolefin can be used without limitation. Among these, polyester is preferable from the viewpoint of mechanical strength, heat resistance, supply stability, and the like, and polyethylene terephthalate is more preferable. Further, the base film may be an unstretched film or a stretched film. When it is a stretched film, it may be a uniaxially stretched film or a biaxially stretched film. Of these, a biaxially stretched polyethylene terephthalate film is preferable.

When the base film itself has releasability, the base film can be used as it is as a releasable film. Further, a surface treatment such as a corona treatment, a plasma treatment, or a flame treatment may be performed in order to adjust the releasability of the base film.

The releasable film may have a releasable layer on the base film. Examples of the release layer include silicone-based, amino resin-based, alkyd resin-based, long-chain acrylic resin-based, and the like, and the composition and type thereof can be appropriately selected according to the required peeling force.

The releasable film may have an easily adhesive layer between the base film and the releasable layer. As the easy-adhesion layer, those conventionally used in each base film such as polyester, acrylic, and polyurethane can be used, and can be selected according to the base film to be used and / or the release layer. ..

(Antistatic layer)
The laminated body for transferring a circularly polarizing element may have an antistatic layer on a releasable film. The antistatic layer is preferably provided between the base film and the release layer, or on the back surface of the base film (opposite the release surface). It is also preferable that an antistatic agent is added to the release layer so that the release layer has antistatic properties.

The antistatic layer is not particularly limited as long as it is a layer containing an antistatic agent. Antistatic agents include cationic antistatic agents such as quaternary ammonium salts; conductive polymers such as polyaniline and polythiophene; acicular metal fillers; conductive high refractive index such as tin-doped indium oxide fine particles and antimony-doped tin oxide fine particles. Examples include fine particles. Only one type of antistatic agent may be used, or two or more types may be used in combination.

The antistatic layer preferably contains a binder resin in addition to the antistatic agent. As the binder resin, for example, polyester, polyurethane, polyamide, acrylic and the like are used. Only one type of binder resin may be used, or two or more types may be used in combination.

(Polarizer)
Examples of the polarizer (also referred to as a polarizing plate, a polarizing film, a polarizing layer, etc.) include a uniaxially stretched polyvinyl alcohol (PVA) in which iodine or an organic bicolor dye is adsorbed (PVA polarizer). A composition obtained by coating (or coating) and orienting a composition composed of a liquid crystal compound and a bicolor dye (liquid crystal polarizer), a wire grid polarizing element, or the like can be used. In addition, in this specification, coating includes not only a wet process of coating and solidifying a liquid, but also a dry process such as vapor deposition, sputtering, and CVD.

Examples of the method of providing the polarizing element on the λ / 4 retardation layer or the releasable film include the methods (a) and (b) in the case of the PVA polarizer.
(A) A method of bonding PVA polarizers alone.
(B) A method for transferring a PVA polarizer on a releasable substrate.

Examples of the method (a) include a method in which a single PVA polarizer is bonded using an adhesive or an adhesive, and is applied to the release surface of the release film or the λ / 4 retardation layer on the release film. A method of adhering PVA polarizers using an adhesive or an adhesive is preferable. The thickness of this type of polarizer is preferably 5 to 50 μm, more preferably 10 to 30 μm, and particularly preferably 12 to 25 μm. The thickness of the adhesive or the pressure-sensitive adhesive is preferably 1 to 10 μm, more preferably 2 to 5 μm.

In the method (b), examples of the releasable substrate include those listed as releasable films, and unstretched or uniaxially stretched films such as PET or polypropylene are preferable. As a method of laminating a PVA polarizer on a releasable base material, PVA is applied to the releasable base material, stretched together with the releasable base material, and iodine or an organic dichroic dye is applied to the PVA. After adsorbing, a method of fixing the orientation with a boron compound can be mentioned. In addition, in this specification, a laminate of a releasable base material and a PVA polarizer may be referred to as a "laminate for PVA polarizer transfer".

If the laminate for circularly polarizing element transfer is laminated in the order of releasable film-polarizer-λ / 4 retardation layer, the polarizer of the laminate for PVA polarizer transfer is released from the releasable film. It may be transferred to the mold surface to be a "removable film-polarizer", but it is preferable that the PVA polarizer transfer laminate is directly used as a "removable film-polarizer". Further, if the laminate for transferring the circularly polarizing element is one in which the releasable film-λ / 4 retardation layer-polarizer is laminated in this order, the polarizer of the laminate for transferring the PVA polarizer is a releasable film. It is preferable to transfer to the upper λ / 4 retardation layer. As a transfer method, a λ / 4 retardation layer on a releasable film is attached to the polarizer surface (the surface on which the releasable base material is not laminated) of the PVA polarizer transfer laminate with an adhesive or an adhesive. In addition, there is a method of peeling off the releasable substrate if necessary. The thickness of this type of polarizer is preferably 1 to 10 μm, more preferably 2 to 8 μm, and particularly preferably 3 to 6 μm. The thickness of the adhesive or the pressure-sensitive adhesive is preferably 1 to 10 μm, more preferably 2 to 5 μm.

As the adhesive for bonding, a polyvinyl alcohol-based adhesive, an ultraviolet curable adhesive such as acrylic and epoxy, and a thermosetting adhesive such as epoxy and isocyanate (urethane) are preferably used. Further, the adhesive may be a hot melt adhesive. Examples of the adhesive include acrylic, urethane, and rubber. Further, as the pressure-sensitive adhesive, it is also preferable to use an acrylic-based transparent pressure-sensitive adhesive sheet for optics without a base material.

Examples of the method of providing the polarizing element on the λ / 4 retardation layer or the releasable film include the methods (c) and (d) in the case of the liquid crystal polarizer.
(C) A method of applying a paint for a liquid crystal polarizer.
(D) A method for transferring a liquid crystal polarizer on a releasable substrate.

As the method (c), a liquid crystal polarizer coating material containing a liquid crystal compound is applied to the release surface of the release film or the λ / 4 retardation layer on the release film to orient the liquid crystal compound. And the method of fixing. As a method of orienting and fixing the liquid crystal compound, a method of applying a liquid crystal polarizer paint on a rubbing-treated surface, heating and aligning the liquid crystal compound, and then curing and fixing with ultraviolet rays; Examples thereof include a method of irradiating polarized ultraviolet rays after coating to align and fix the liquid crystal compound. Further, before applying the liquid crystal polarizer paint, an orientation control layer is provided on the release surface of the release film or the λ / 4 retardation layer on the release film, that is, the release film is released. It is also a preferable method to laminate a liquid crystal polarizer on a λ / 4 retardation layer on a mold surface or a releasable film via an orientation control layer.

As the method (d), a liquid crystal polarizer is laminated on a releasable base material according to the above method (c), and an adhesive or an adhesive is used on the releasable substrate to release the release surface of the releasable film. Alternatively, a method of laminating the λ / 4 retardation layer on the releasable film and peeling off the releasable base material as necessary can be mentioned. Examples of the adhesive and the adhesive for bonding include the above-mentioned ones. As the releasable base material, those listed as the releasable base material of the laminate for PVA polarizer transfer, a metal belt, and the like can be used. In addition, in this specification, a laminate of a releasable base material and a liquid crystal polarizer may be referred to as a "laminate for transfer of a liquid crystal polarizer".

The thickness of the liquid crystal polarizer is preferably 0.1 to 7 μm, more preferably 0.3 to 5 μm, and particularly preferably 0.5 to 3 μm. The thickness of the adhesive or the pressure-sensitive adhesive is preferably 1 to 10 μm, more preferably 2 to 5 μm.

Further, the orientation control layer and the liquid crystal polarizer will be described in detail.
(Orientation control layer)
The paint for a liquid crystal polarizer may be directly applied to a release film or a λ / 4 retardation layer, but a method in which an orientation control layer is provided in advance and the coating is applied on the orientation control layer is also preferable. In the present specification, the orientation control layer and the liquid crystal polarizer may be regarded as one member, and the member may be referred to as a liquid crystal polarizer. The liquid crystal polarizer to be combined with the orientation control layer is sometimes called a liquid crystal polarizing layer in order to clearly distinguish it from the generic liquid crystal polarizer.

The orientation control layer may be any orientation control layer as long as the liquid crystal compound can be brought into a desired orientation state. Preferable examples of the orientation control layer are a rubbing treatment orientation control layer whose surface is rubbed and a photoalignment control layer in which molecules are oriented by irradiation with polarized light to generate an orientation function.

(Rubbing treatment orientation control layer)
A polymer is usually used as a material for the rubbing treatment orientation control layer. As the polymer, polyvinyl alcohol and its derivatives, polyimide and its derivatives, acrylic resins, polysiloxane derivatives and the like are preferably used. Only one type of polymer may be used, or two or more types may be used in combination.

As a method for forming the rubbing treatment orientation control layer, the surface of the coating film obtained by applying the coating material for the rubbing treatment orientation control layer containing the above polymer and solvent to the release film or the λ / 4 retardation layer is subjected to the rubbing treatment. A method including the step of performing is preferable. The coating material for the rubbing treatment orientation control layer may contain a cross-linking agent.

The solvent for the paint for the rubbing treatment orientation control layer can be used without limitation as long as it dissolves the polymer material. Specific examples include water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, cellosolve and other alcohols; ester solvents such as ethyl acetate, butyl acetate and gamma butyrolactone; acetone, methyl ethyl ketone, cyclopentanone and cyclohexanone. Ketone-based solvents; aromatic hydrocarbon solvents such as toluene or xylene; ether-based solvents such as tetrahydrofuran or dimethoxyethane can be mentioned. Only one type of solvent may be used, or two or more types may be used in combination.

The concentration of the polymer in the coating for the rubbing treatment orientation control layer can be appropriately adjusted depending on the type of polymer and the thickness of the orientation control layer to be manufactured, but it should be 0.2 to 20% by mass in terms of solid content concentration. Is preferable, and the range of 0.3 to 10% by mass is particularly preferable.

As the coating method, known methods such as a gravure coating method, a die coating method, a coating method such as a bar coating method and an applicator method, and a printing method such as a flexographic method can be adopted.

It is preferable to dry (for example, heat dry) after application. The drying temperature depends on the material of the release film, but in the case of PET, it is preferably 30 ° C. to 170 ° C., more preferably 50 to 150 ° C., and further preferably 70 to 130 ° C. If the drying temperature is in such a range, it is not necessary to take a long drying time and the productivity is excellent, the optical function as designed can be achieved without heat elongation and heat shrinkage of the alignment film for transfer, and the flatness is also excellent. .. The drying time is, for example, 0.5 to 30 minutes, more preferably 1 to 20 minutes, still more preferably 2 to 10 minutes.

The thickness of the rubbing treatment orientation control layer is preferably 0.01 to 10 μm, more preferably 0.05 to 5 μm, and particularly preferably 0.1 μm to 1 μm.

The rubbing treatment can generally be carried out by rubbing the surface with paper or cloth in a certain direction. The rubbing treatment is preferably a method using a rubbing roller of a brushed cloth made of fibers such as nylon, polyester and acrylic. When the orientation control layer is provided so as to be oriented in a predetermined direction diagonally with respect to the longitudinal direction of the long film, the rubbing direction is preferably set to an angle suitable for the direction. The angle can be adjusted by adjusting the angle between the rubbing roller and the film, adjusting the transport speed of the film and the rotation speed of the roller, and the like.

(Photo-orientation control layer)
For the photo-orientation control layer, a paint containing a polymer and / or a monomer having a photoreactive group and a solvent (paint for a photo-orientation control layer) is applied to a releasable film or a λ / 4 retardation layer, and polarized light is preferable. Is preferably an alignment film to which an orientation regulating force is imparted by irradiating with polarized ultraviolet rays. The photoreactive group is preferably a group that produces a liquid crystal orientation ability by irradiation with light, and specifically, an orientation-inducing or isomerization reaction, a dimerization reaction, and a photocrosslinking reaction of molecules generated by irradiation with light. , Or a group that causes a photoreaction that is the origin of the liquid crystal orientation ability, such as a photodecomposition reaction. Among the photoreactive groups, those that cause a dimerization reaction or a photocrosslinking reaction are preferable in that they have excellent orientation and maintain a smectic liquid crystal state. The photoreactive group capable of causing the above reaction is preferably an unsaturated bond, particularly a double bond, and is a group consisting of a C = C bond, a C = N bond, an N = N bond, and a C = O bond. Groups having at least one selected from the above are particularly preferred.

Examples of the photoreactive group having a C = C bond include a vinyl group, a polyene group, a stilbene group, a stillbazol group, a stillbazolium group, a chalcone group, a cinnamoyl group and the like. Examples of the photoreactive group having a C = N bond include a group having a structure such as an aromatic Schiff base and an aromatic hydrazone. Examples of the photoreactive group having an N = N bond include those having an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bisazo group, a formazan group, and an azoxibenzene as a basic structure. Examples of the photoreactive group having a C = O bond include a benzophenone group, a coumarin group, an anthraquinone group, a maleimide group and the like. These groups may have substituents such as an alkyl group, an alkoxy group, an allyl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group and an alkyl halide group. The number of substituents is not particularly limited, but is, for example, 1, 2, 3, or 4.

Among them, a photoreactive group capable of causing a photodimerization reaction is preferable, and a cinnamoyl group and a chalcone group are a photo-orientation control layer in which the amount of polarized light required for photo-orientation is relatively small and the thermal stability and temporal stability are excellent. Is preferable because it is easy to obtain. Further, as the polymer having a photoreactive group, a polymer having a cinnamoyl group such that the terminal portion of the side chain of the polymer has a cinnamic acid structure is particularly preferable. Examples of the structure of the main chain include polyimide, polyamide, (meth) acrylic, polyester and the like.

Specific examples of the orientation control layer include JP-A-2006-285197, JP-A-2007-76839, JP-A-2007-138138, JP-A-2007-94071, and JP-A-2007-121721. , JP-A-2007-140465, JP-A-2007-156439, JP-A-2007-133184, JP-A-2009-109831, JP-A-2002-229039, JP-A-2002-265541, Orientation described in Kai 2002-317013, Japanese Patent Application Laid-Open No. 2003-520878, Japanese Patent Application Laid-Open No. 2004-522220, Japanese Patent Application Laid-Open No. 2013-33248, Japanese Patent Application Laid-Open No. 2015-7702, Japanese Patent Application Laid-Open No. 2015-129210. A control layer can be mentioned.

The solvent for the paint for the photo-orientation control layer can be used without limitation as long as it dissolves a polymer and a monomer having a photoreactive group. As a specific example, the one mentioned in the method of forming the rubbing treatment orientation control layer can be exemplified. It is also preferable to add a photopolymerization initiator, a polymerization inhibitor, and various stabilizers to the coating material for the photoalignment control layer. Further, a polymer having a photoreactive group, a polymer other than the monomer, and a monomer having no photoreactive group copolymerizable with the monomer having a photoreactive group may be added to the coating material for the photoorientation control layer.

Examples of the polymer or monomer concentration, coating method, and drying conditions of the coating material for the photo-orientation control layer are also those listed in the method for forming the rubbing treatment orientation control layer. The thickness is also the same as the preferable thickness of the rubbing treatment orientation control layer.

It is preferable to irradiate the polarized light from the direction of the photo-alignment control layer surface before orientation.

The wavelength of polarization is preferably in the wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, ultraviolet rays having a wavelength in the range of 250 to 400 nm are preferable. Examples of the polarized light source include xenon lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, ultraviolet light lasers such as KrF and ArF, and high-pressure mercury lamps, ultra-high pressure mercury lamps, and metal halide lamps are preferable. ..

Polarized light is obtained, for example, by passing light from the light source through a polarizer. The direction of polarization can be adjusted by adjusting the polarization angle of the polarizer. Examples of the polarizer include a polarizing filter, a polarizing prism such as a Gran Thomson and a Granter, and a wire grid type polarizer. The polarized light is preferably substantially parallel light.

By adjusting the angle of the polarized light to be irradiated, the direction of the orientation regulating force of the optical orientation control layer can be arbitrarily adjusted.

The irradiation intensity is different in kind and amount of a polymerization initiator or a resin (monomer), for example, preferably 10 ~ 10000mJ / cm ² at 365nm reference, and more preferably 20 ~ 5000mJ / cm ^2.

(Liquid crystal polarizer)
The liquid crystal polarizer has a function as a polarizer that allows light to pass through in only one direction, and preferably contains a dichroic dye.

<Dichroic pigment>
The dichroic dye is preferably an organic dye having a property that the absorbance in the major axis direction and the absorbance in the minor axis direction of the molecule are different.

The dichroic dye preferably has an absorption maximum wavelength (λMAX) in the range of 300 to 700 nm. Examples of such a dichroic dye include an acrydin dye, an oxazine dye, a cyanine dye, a naphthalene dye, an azo dye, an anthraquinone dye, and the like, and among them, the azo dye is preferable. Examples of the azo dye include a monoazo dye, a bisazo dye, a trisazo dye, a tetrakisazo dye, a stilbene azo dye, and the like, and a bisazo dye and / or a trisazo dye is preferable. The dichroic dye may be used alone or in combination of two or more, but it is preferable to combine two or more in order to adjust the color tone (achromatic color). In particular, it is preferable to combine three or more types. In particular, it is preferable to combine three or more kinds of azo compounds.

Preferred azo compounds include dyes described in JP-A-2007-126628, JP-A-2010-168570, JP-A-2013-101328, and JP-A-2013-210624.

It is also a preferable form that the dichroic dye is a dichroic dye polymer introduced into the side chain of a polymer such as acrylic. Examples of the dichroic dye polymer include polymers listed in JP-A-2016-4055 and polymers obtained by polymerizing compounds [Chemical formula 6] to [Chemical formula 12] in JP-A-2014-206682.

The content of the dichroic dye in the liquid crystal polarizer is preferably 0.1 to 30% by mass, preferably 0.5 to 20% by mass in the liquid crystal polarizer from the viewpoint of improving the orientation of the dichroic dye. More preferably, 1.0 to 15% by mass is further preferable, and 2.0 to 10% by mass is particularly preferable.

It is preferable that the liquid crystal polarizer further contains a polymerizable liquid crystal compound in order to improve the film strength, the degree of polarization, and the film homogeneity. The polymerizable liquid crystal compound also includes a film after polymerization.

<Polymerizable liquid crystal compound>
The polymerizable liquid crystal compound is preferably a compound having a polymerizable group and exhibiting liquid crystallinity.
The polymerizable group means a group involved in the polymerization reaction, and is preferably a photopolymerizable group. Here, the photopolymerizable group refers to a group that can undergo a polymerization reaction with an active radical, an acid, or the like generated from a photopolymerization initiator described later. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloyloxy group, a methacryloyloxy group, an oxylanyl group, an oxetanyl group and the like. Of these, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxylanyl group, and an oxetanyl group are preferable, and an acryloyloxy group is more preferable. The liquid crystal compound may be a thermotropic liquid crystal or a riotropic liquid crystal. The thermotropic liquid crystal may be a nematic liquid crystal or a smectic liquid crystal.

As the polymerizable liquid crystal compound, a smectic liquid crystal compound is preferable in that higher polarization characteristics can be obtained, and a higher-order smectic liquid crystal compound is more preferable. When the liquid crystal phase formed by the polymerizable liquid crystal compound is a higher-order smectic phase, a liquid crystal polarizer having a higher degree of orientation order can be produced.

Specific preferred polymerizable liquid crystal compounds include, for example, JP-A-2002-308832, JP-A-2007-16207, JP-A-2015-163596, JP-A-2007-510946, JP-A-2013-114131. No., WO2005 / 045485, Lub et al. Recl.Trav.Chim.Pays-Bas, 115, 321-328 (1996) and the like.

The content ratio of the polymerizable liquid crystal compound in the liquid crystal polarizer is preferably 70 to 99.5% by mass, more preferably 75 to 99% by mass in the liquid crystal polarizer from the viewpoint of increasing the orientation of the polymerizable liquid crystal compound. It is more preferably 80 to 97% by mass, and particularly preferably 83 to 95% by mass.

The liquid crystal polarizer can be provided by applying a paint for the liquid crystal polarizer. The paint for a liquid crystal polarizer may contain additives such as a solvent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a leveling agent, a polymerizable non-liquid crystal compound, and a cross-linking agent. Only one type of additive may be used, or two or more types may be used in combination.

As the solvent, those listed as the solvent for the paint for the orientation control layer are preferably used.

The polymerization initiator is not limited as long as it polymerizes a polymerizable liquid crystal compound, but a photopolymerization initiator that generates active radicals by light is preferable. Examples of the polymerization initiator include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts, sulfonium salts and the like.

As the sensitizer, a photosensitizer is preferable, and examples thereof include xanthone compounds, anthracene compounds, phenothiazines, and rubrenes.

Examples of the polymerization inhibitor include hydroquinones, catechols, and thiophenols.

The polymerizable non-liquid crystal compound is preferably one that copolymerizes with the polymerizable liquid crystal compound, and examples thereof include (meth) acrylates when the polymerizable liquid crystal compound has a (meth) acryloyloxy group. The (meth) acrylates may be monofunctional or polyfunctional. By using polyfunctional (meth) acrylates, the strength of the polarizer can be improved. When a polymerizable non-liquid crystal compound is used, the content thereof is preferably 1 to 15% by mass, more preferably 2 to 10% by mass, and particularly 3 in the liquid crystal polarizer in order to suppress a decrease in the degree of polarization. It is preferably about 7% by mass.

Examples of the cross-linking agent include a polymerizable liquid crystal compound and a compound capable of reacting with a functional group of a polymerizable non-liquid crystal compound, and examples thereof include an isocyanate compound, a melamine, an epoxy resin, and an oxazoline compound.

A liquid crystal polarizer can be produced by applying a paint for a liquid crystal polarizer on a release film, a λ / 4 retardation layer, or an orientation control layer, and then drying, heating, and curing as necessary. ..

Drying is preferably performed in a dryer (warm air dryer, infrared dryer, etc.) at a temperature of 30 to 170 ° C. The drying temperature is more preferably 50 to 150 ° C., further preferably 70 to 130 ° C., and the drying time is preferably 0.5 to 30 minutes, more preferably 1 to 20 minutes, still more preferably 2 to 10 minutes. preferable.

Heating can be performed to more strongly orient the dichroic dye and the polymerizable liquid crystal compound in the liquid crystal polarizer. The heating temperature is preferably in the temperature range in which the polymerizable liquid crystal compound forms a liquid crystal phase.

When the liquid crystal polarizer paint contains a polymerizable liquid crystal compound, it is preferably cured. Examples of the curing method include heating and light irradiation, and light irradiation is preferable. By curing, the dichroic dye can be fixed in an oriented state. The curing is preferably carried out in a state where the polymerizable liquid crystal compound has a liquid crystal phase formed therein, and may be cured by irradiating light at a temperature indicating the liquid crystal phase. Examples of the light in the light irradiation include visible light, ultraviolet light and laser light. Ultraviolet light is preferable because it is easy to handle.

The irradiation intensity is different in kind and amount of a polymerization initiator or a resin (monomer), for example, preferably 100 ~ 10000mJ / cm ² at 365nm reference, more preferably 200 ~ 5000mJ / cm ^2.

In the liquid crystal polarizer, by applying the coating material for the liquid crystal polarizer on the alignment control layer, the dye is oriented along the orientation direction of the alignment layer and has a polarization transmission axis in a predetermined direction. If the above is not provided, the liquid crystal polarizer can be oriented by irradiating polarized light to cure the liquid crystal compound-containing composition.

Any method may be used for providing the polarizer, but the methods (b), (c), and (d) are particularly preferable.

(Λ / 4 phase difference layer)
The λ / 4 retardation layer can convert light that has been linearly polarized by the polarizer into circularly polarized light. As the λ / 4 retardation layer, a coat layer coated with a paint for a λ / 4 retardation layer is preferable, and a coat layer coated with a paint containing a liquid crystal compound or a polymer compound is more preferable. A coat layer coated with a paint containing a liquid crystal compound is particularly preferable.

Examples of the polymer compound used for the λ / 4 retardation layer include polymers such as polyimide, polyamideimide, polyester, polyetherketone, polyaryletherketone, and polyesterimide having at least one aromatic ring in the repeating unit. Be done.

As the liquid crystal compound used for the λ / 4 retardation layer, a rod-shaped liquid crystal compound is preferable, and a polymerizable rod-shaped liquid crystal compound having a polymerizable group such as a double bond is preferable in terms of being able to fix the orientation state.

Examples of the rod-shaped liquid crystal compound include JP-A-2002-030042, JP-A-2004-204190, JP-A-2005-263789, JP-A-2007-119415, JP-A-2007-186430, and special publications. Examples thereof include rod-shaped liquid crystal compounds having a polymerizable group described in Kaihei 11-513360.

As a specific rod-shaped liquid crystal compound,
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-Ph2-OCO-Ph1-O- (CH ₂ ) _n -OCO-CH = CH ₂
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-NPh-OCO-Ph1-O- (CH ₂ ) _n -OCO-CH = CH ₂
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-Ph2-OCH ₃
CH ₂ = CHCOO- (CH ₂ ) _m- O-Ph1-COO-Ph1-Ph1-CH ₂ CH (CH ₃ ) C ₂ H ₅
(During the ceremony,
m and n are integers from 2 to 6
Ph1 and Ph2 are 1,4-phenylene groups (Ph2 may have a methyl group substituted at the 2-position).
NPh is a 2,6-naphthylene group)
Can be mentioned.

These rod-shaped liquid crystal compounds are commercially available from BASF as LC242 and the like, and they can be used.

A plurality of types of these rod-shaped liquid crystal compounds may be used in combination at any ratio.

The method of forming the λ / 4 retardation layer may be a method of applying the paint for the λ / 4 retardation layer to the release surface of the release film or the polarizer on the release film. A method of transferring the λ / 4 retardation layer on the mold base material to a polarizer may be used. The laminate of the releasable base material and the λ / 4 retardation layer may be referred to as a "laminate for transfer of the retardation layer". As the releasable base material of the retardation layer transfer laminate, those listed in the releasable substrate of the PVA polarizer laminate can be used.

The λ / 4 retardation layer coating material may contain a solvent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a leveling agent, a polymerizable non-liquid crystal compound, a cross-linking agent and the like. As these, those described in the orientation control layer or the liquid crystal polarizer can be used.

As a method for orienting the liquid crystal compound used for the λ / 4 retardation layer, the same method as the above-mentioned orientation of the liquid layer polarizer can be adopted. That is, a method of directly applying a paint for a λ / 4 retardation layer to a releasable film or a polarizer to irradiate polarized ultraviolet rays, a method of rubbing the surface of a releasable film or a polarizer, a polarizer and λ. A method of providing an orientation control layer between the / 4 retardation layers can be mentioned. As for these conditions, the conditions described in the orientation control layer or the liquid crystal polarizer are used as preferable conditions.

The λ / 4 retardation layer may be a single λ / 4 retardation layer, or may be a composite λ / 4 retardation layer of a λ / 4 retardation layer and a λ / 2 retardation layer. .. In the present specification, the single λ / 4 retardation layer and the composite λ / 4 retardation layer may be collectively referred to as a λ / 4 retardation layer, and other retardation layers such as the C plate layer described later. May also be referred to as a λ / 4 retardation layer.

The in-plane retardation of the λ / 4 retardation layer is preferably 100 to 180 nm, more preferably 120 to 150 nm. The in-plane retardation of the λ / 2 retardation layer is preferably 200 to 360 nm, more preferably 240 to 300 nm.

(Angle of slow axis of λ / 4 retardation layer)
In the case of a single λ / 4 retardation layer, the angle formed by the orientation axis (slow phase axis) of the λ / 4 retardation layer and the transmission axis of the polarizer is preferably 35 to 55 degrees, more preferably 40 to 50 degrees. Degrees, more preferably 42-48 degrees.

In the case of a composite λ / 4 retardation layer in which a λ / 4 retardation layer and a λ / 2 retardation layer are combined, the orientation axis (slow phase axis) of each retardation layer is λ / 4 phase difference between the two layers. It is preferable that they are arranged at such an angle. Specifically, the angle (θ) formed by the orientation axis (slow phase axis) of the λ / 2 retardation layer and the transmission axis of the polarizer is preferably 5 to 20 degrees, more preferably 7 to 17 degrees. The angle formed by the orientation axis (slow phase axis) of the λ / 2 retardation layer and the orientation axis (slow phase axis) of the λ / 4 retardation layer is preferably in the range of 2θ + 45 degrees ± 10 degrees, more preferably 2θ + 45 degrees ±. It is in the range of 5 degrees, more preferably in the range of 2θ + 45 degrees ± 3 degrees.

Examples of the λ / 4 retardation layer include JP-A-2008-149757, JP-A-2002-303722, WO2006 / 100830, JP-A-2015-64418, JP-A-2018-10086, and the like. It can be used as a reference.

Further, in order to reduce the change in coloring when viewed from an angle, it is also a preferable form to provide a C plate layer on the λ / 4 retardation layer. As the C plate layer, a positive or negative C plate layer is selected according to the characteristics of the λ / 4 retardation layer and the λ / 2 retardation layer.

In the composite λ / 4 retardation layer, for example, as a method of laminating the λ / 4 retardation layer and the λ / 2 retardation layer, for example,
-A method in which a λ / 2 retardation layer is provided on the polarizer by transfer and a λ / 4 retardation layer is provided on the polarizer by transfer.-A λ / 2 retardation layer is provided on the polarizer by transfer and λ is provided on the λ / 2 retardation layer. A method of providing a / 4 retardation layer by coating ・ A method of providing a λ / 2 retardation layer on a polarizer by coating and a λ / 4 retardation layer on it by transfer ・ λ / 2 on a polarizer Method of providing a retardation layer and a λ / 4 retardation layer by coating ・ A λ / 4 retardation layer and a λ / 2 retardation layer are provided in this order on a releasable substrate, and these are transferred onto a polarizer. The method can be mentioned.

As a method of laminating the C plate on the λ / 4 retardation layer, a method of providing the C plate layer on the λ / 4 retardation layer by transfer, a method of providing the C plate layer on the releasable substrate, and further Various methods can be adopted, such as a method in which a single λ / 4 retardation layer or a composite λ / 4 retardation layer is provided on the top and these are transferred to a polarizer.

(Interlayer protective layer)
The laminated body for transferring a circularly polarizing element includes a plurality of layers between any two layers (for example, between a polarizer and a λ / 4 retardation layer, a surface on which the λ / 4 retardation layer is not laminated, and a plurality of layers. An interlayer protective layer may be provided between the retardation layers, between the adhesive or the pressure-sensitive adhesive and the polarizer or the λ / 4 retardation layer). The interlayer protection layer can prevent the components of each layer or the solvent used from migrating to other adjacent layers, causing a decrease in the degree of polarization or a change in the phase difference. The interlayer protection layer may be provided on the releasable substrate together with the λ / 4 retardation layer and / or the polarizer and transferred to the target.

Examples of the interlayer protection layer include a transparent resin layer. Examples of the transparent resin include, but are not limited to, polyvinyl alcohol, ethylene vinyl alcohol copolymer, polyester, polyurethane, polyamide, polystyrene, acrylic resin, epoxy resin and the like. The transparent resin may be crosslinked with a crosslinking agent to form a crosslinked structure. Further, a curable (for example, photocurable) composition such as acrylic such as a hard coat may be cured (for example, photocurable). Further, the interlayer protection layer may also serve as an orientation control layer.

In order to protect the surface (polarizer surface, λ / 4 retardation layer surface, etc.) transferred to the surface of the target surface, the circular polarizing element transfer laminate may have a masking film bonded to that surface. Good. As the masking film, a base material such as polyethylene, polypropylene, or polyester provided with an adhesive layer such as acrylic, rubber, or polyolefin is preferably used. Instead of the masking fill, the releasable substrate used for transferring the polarizer, the λ / 4 retardation layer, or the like may remain.

The circular polarization element transfer laminate can be provided with a circular polarization element containing a λ / 4 retardation layer and a polarizer on the surface of the target by transferring to the surface of the target. When transferring to the subject, the above-mentioned adhesive or adhesive can be used. The adhesive or pressure-sensitive adhesive for transferring to the target may be provided in advance on the laminated body for transferring the circular polarization element. In this case, a separator may be further laminated on the adhesive layer or the adhesive layer. As the separator, those mentioned in the releasable base material of the laminate for PVA polarizer transfer can be used. The releasable base material and the masking film are preferably peeled off immediately before being transferred to the target or immediately before the adhesive layer or the pressure-sensitive adhesive layer is provided.

It is preferable that the laminated body for transferring a circularly polarizing element does not have a self-supporting film other than a film for a manufacturing process as a constituent layer. A self-supporting film is an independently manufactured film. Examples of the self-supporting film include a polarizer protective film. The film for a manufacturing process is a member used for manufacturing a laminate for transferring a circularly polarizing element, but is finally removed by an image display device. For example, a releasable film, a releasable base material, and masking. Examples include films and separators. Each layer constituting the laminated body for transferring a circularly polarizing element other than the film for a manufacturing process does not exist by itself, and is preferably provided by coating or by transfer. This makes it possible to further reduce the thickness and weight.

(Transfer target)
Circular polarization element Examples of the target for providing the circular polarization element using the transfer laminate include the substance itself that causes reflection and the transparent substance that exists between the substance that causes reflection and the observer. Not limited. Preferred objects include a transparent conductive base material and a transparent base material for a surface cover.

The circular polarization element transfer laminate is laminated on the target surface so that the λ / 4 retardation layer or the polarizer of the circular polarization element transfer laminate is arranged on the target surface, and the releasable film is peeled off. This makes it possible to provide a circularly polarizing element on the surface of the target. It should be noted that the releasable film of the laminated body for transferring the circularly polarizing element does not need to be peeled off immediately after the lamination, and is not peeled off for surface protection until the final form (or until the use). It may be peeled off immediately before it becomes the final form (or immediately before it is used).

(Transparent conductive base material with circular polarization element)
The transparent conductive base material having the circular polarization element is preferably one in which a laminate for transferring the circular polarization element is laminated (transferred) on the transparent conductive base material. The transparent conductive base material preferably has a transparent conductive layer provided on at least one side (preferably both sides) of the transparent base material. Examples of the transparent base material include resin films such as glass, PET, TAC, COP, acrylic, and polycarbonate. Examples of the transparent conductive layer include a resin coat in which tin-doped indium oxide, a metal mesh, a mesh of a conductive paste, a needle-like metal filler, CNT, and the like are dispersed. By laminating the circularly polarized light element on the transparent conductive base material using the laminated body for transferring the circularly polarized light element, the transparent conductive base material has an antireflection function by the circularly polarized light element without substantially increasing the thickness. Can be made.

In one embodiment, a method for producing a transparent conductive base material having a circular polarization element is used.
(A) The λ / 4 retardation layer of the laminated body for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a releasable film on a transparent conductive substrate, is transparently conductive. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (B) the transparent conductive substrate has a λ / 4 retardation layer and a polarizer on the releasable film. It is preferable to include a step of laminating the circularly polarizing element transfer laminate so that the polarizers of the circularly polarizing element transfer laminates laminated in this order are arranged on the transparent conductive base material side.

(Touch panel with circular polarization element)
The touch panel having the circular polarization element is preferably one in which a laminate for transferring the circular polarization element is laminated (transferred) on the transparent conductive base material of the touch panel. Examples of the transparent conductive base material include the same as those described above. By laminating the circularly polarized light element on the transparent conductive base material of the touch panel using the laminated body for transferring the circularly polarized light element, the touch panel is provided with the antireflection function by the circularly polarized light element without substantially increasing the thickness. Can be done.

The circular polarization element may be provided on either the transparent base material side or the transparent conductive layer side of the transparent conductive base material. Further, when the coat layer or the like is present on the transparent conductive layer, the circular polarization element may be provided on the coat layer or the like.

A circularly polarized element may be provided on the transparent conductive base material before the touch panel is processed, or a circularly polarized element may be provided at an intermediate stage of the touch panel processing or after the processing. The circularly polarized light element may be provided on the surface on the visual side of the touch panel or on the surface on the opposite side (the surface on the image display cell side). Further, in the case of a capacitance type touch panel, the circular polarization element may exist as a part of the dielectric layer between the two transparent conductive base materials.

When the image display cells are stacked on the touch panel, the circularly polarized light element may exist as an intermediate layer between the touch panel and the image display cells. When the surface cover is laminated on the touch panel, the circularly polarized light element may exist as an intermediate layer between the touch panel and the surface cover.

In one embodiment, a method for manufacturing a touch panel having a circularly polarized light element is used.
(C) The λ / 4 retardation layer of a laminate for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a transparent conductive base material of a touch panel, is described above. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the transparent conductive base material side, or (D) λ / 4 phase difference on the releasable film on the transparent conductive base material of the touch panel. The step of laminating the circularly polarizing element transfer laminate is included so that the polarizer of the circular polarization element transfer laminate in which the layers and the polarizers are laminated in this order is arranged on the transparent conductive substrate side. Is preferable.

(Transparent base material for surface cover)
The transparent base material for a surface cover having a circular polarization element is preferably one in which a laminate for transferring a circular polarization element is laminated (transferred) on the transparent base material for a surface cover. Examples of the transparent base material for the surface cover include a glass plate, acrylic, polyester, polycarbonate, polystyrene, polypropylene, polymethylpentene, a film or sheet of polyurethane or the like.

When the image display cell is laminated on the surface cover, the circular polarization element may exist as an intermediate layer between the surface cover and the image display cell.

In one embodiment, a method for manufacturing a transparent base material for a surface cover having a circularly polarizing element is used.
(E) The λ / 4 retardation layer of the multilayer body for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a releasable film on a transparent substrate for a surface cover, is transparent. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (F) the transparent substrate for the surface cover, the λ / 4 retardation layer and the polarizer on the releasable film. It is preferable to include a step of laminating the circularly polarizing element transfer laminate so that the polarizer of the circularly polarizing element transfer laminate laminated in this order is arranged on the transparent substrate side. The transparent base material is preferably a transparent base material for a surface cover of an image display device.

(Image display device)
The image display device can be used without particular limitation as long as it has a function of preventing reflection by a circularly polarizing element. The image display device preferably has the transparent conductive base material having the above-mentioned circular polarization element, the touch panel having the circular polarization element, or the surface cover having the circular polarization element. For example, the image display device has a transparent conductive base material, a circular polarization element, and an image display cell in this order, has a circular polarization element, a transparent conductive base material, and an image display cell in this order, and a touch panel. , The circular polarization element, and the image display cell in this order, the circular polarization element, the touch panel, and the image display cell in this order, or the surface cover, the circular polarization element, and the image display cell in this order. That is preferable. Further, as the image display device, for example, an organic EL display device, a micro LED display device, or the like is a preferable example. Further, it can be suitably used for a foldable type (folding type) or rollable type (winding type) image display device. The image display device of the present invention can be made thinner, and has good foldability and winding property.

In one embodiment, a method for manufacturing an image display device having a circularly polarized light element is used.
(G) A step of providing the touch panel in the image display device so that the touch panel of the touch panel having the circular polarization element is arranged on the visual recognition side (so that the circular polarization element is arranged on the image display cell side).
(H) A step of providing the touch panel in the image display device so that the circular polarization element of the touch panel having the circular polarization element is arranged on the viewing side (so that the touch panel is arranged on the image display cell side), or (I). ) The transparent base material for the surface cover having the circular polarization element is arranged so that the transparent base material for the surface cover is arranged on the viewing side (so that the circular polarization element is arranged on the image display cell side). It is preferable to include a step of providing the image display device.

Hereinafter, the present invention will be described in more detail with reference to Examples. In the present invention, it is preferable that the laminate for transferring a circular polarization element is transferred to a transparent conductive base material. The present invention is not limited to the following examples, and it is also possible to carry out modifications as appropriate to the extent that the gist of the present invention can be met. All of them are included in the technical scope of the present invention.

The retardation measurement of the retardation layer in the laminated body of the example is as follows.

(Measurement of retardation of retardation layer)
An orientation control layer and a retardation layer are provided on the non-easy adhesive layer surface of a polyester film having a thickness of 50 μm (Cosmo Shine (TM) A4100 manufactured by Toyobo Co., Ltd.) under the same conditions as in the examples described later, and this is a glass plate (35 mm). It was transferred to × 35 mm) to prepare a sample for measurement. An ultraviolet curable adhesive was used for the transfer.
Using an automatic birefringence meter (KOBRA-WR, Oji Measurement Co., Ltd.), the retardation value (Re) measured from the vertical direction was measured when the wavelength used was 590 nm, and the slow phase in the film plane was measured. The retardation value was measured in the same manner by tilting the axis from 0 degrees to 50 degrees every 10 degrees with respect to the normal direction of the film with the axis as the inclination axis (rotation axis), and Rth was obtained from this value, the thickness, and the average refractive index. ..
The thickness was determined by embedding the film in an epoxy resin, cutting out a cross-sectional section, and observing with a polarizing microscope. The average refractive index used was 1.60.

Each layer in the laminated body of the example will be described below.

(Polarizer)
(1) Laminate for PVA Polarizer Transfer As a thermoplastic resin base material, polyethylene terephthalate having an ultimate viscosity of 0.62 dl / d is melted and kneaded with an extruder, and then extruded into a sheet on a cooling roll to a thickness of 100 μm. A stretched film was produced. An aqueous solution of polyvinyl alcohol having a degree of polymerization of 2400 and a degree of saponification of 99.9 mol% was applied to one side of this unstretched film and dried to form a PVA layer.
The obtained laminate was stretched twice in the longitudinal direction between rolls having different peripheral speeds at 120 ° C. and wound up. Next, the obtained laminate was treated with a 4% boric acid aqueous solution for 30 seconds, then immersed in a mixed aqueous solution of iodine (0.2%) and potassium iodide (1%) for 60 seconds for staining, followed by It was treated with a mixed aqueous solution of potassium iodide (3%) and boric acid (3%) for 30 seconds.
Further, this laminate was uniaxially stretched in the longitudinal direction in a mixed aqueous solution of boric acid (4%) and potassium iodide (5%) at 72 ° C., subsequently washed with a 4% potassium iodide aqueous solution, and the aqueous solution was prepared with an air knife. After removal, the solution was dried in an oven at 80 ° C., both ends were slit and wound to obtain a PVA polarizer transfer laminate having a width of 50 cm and a length of 1000 m. The total draw ratio was 6.5 times, and the thickness of the PVA polarizer was 5 μm. The thickness was read by embedding the PVA polarizer transfer laminate in an epoxy resin, cutting out a section, and observing it with an optical microscope. This PVA polarizer is labeled PVA in Table 1.

(2) Liquid crystal polarizers The following compounds (d) and the following compounds according to the description in paragraph [0134] of JP-A-2007-510946 and Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996). (E) was synthesized.

The following dye (f) was synthesized according to Example 1 of JP-A-63-301850.

The following dye (g) was synthesized according to Example 2 of JP-A-5-49710.

The following dye (h) was synthesized according to the method for producing the compound of the general formula (1) of Japanese Patent Publication No. 63-1357.

(D) 75 parts by mass, (e) 25 parts by mass, (f) 2.5 parts by mass, (g) 2.5 parts by mass, (h) 2.5 parts by mass, IRGACURE ™ 369E (manufactured by BASF) ) 6 parts by mass and 250 parts by mass of ortho-xylene were mixed and dissolved to prepare a coating material for a liquid crystal polarizer. The liquid crystal polarizer obtained by applying this paint is labeled as liquid crystal coating in Table 1.

(Example 1)
(Preparation of Laminate 1 for Transfer of Phase Difference Layer)
Orientation control layer paint with a width of 50 cm (Cosmo Shine (TM) A4100 manufactured by Toyobo Co., Ltd., thickness 50 μm) is applied to the non-easy adhesive layer surface, dried at 100 ° C, and the orientation control layer with a thickness of 0.5 μm. Was formed. Further, the orientation control layer was treated with a rubbing roll wrapped with a nylon blanket. The film was hung diagonally on the rubbing roll, and the direction of the rubbing roll, the running speed of the film, and the number of rotations of the rubbing roll were adjusted so that the rubbing direction was 45 degrees with respect to the flow direction of the film. Subsequently, after applying the retardation layer paint, the solvent was evaporated by heating at 110 ° C. for 3 minutes, and the rod-shaped liquid crystal compound was oriented. Further, it was irradiated with ultraviolet rays for 30 seconds in an environment of 110 ° C. to obtain a stack 1 for transfer of a retardation layer having a length of 200 m. The Re of the retardation layer was 140 nm, and the Rth was 70 nm.

The PVA polarizer transfer laminate and the retardation layer transfer laminate 1 are unwound, and an ultraviolet curable adhesive is applied to the polarizer surface (PVA surface) of the PVA polarizer transfer laminate to form an adhesive surface. After superimposing the retardation layer surface of the retardation layer transfer laminate 1, the retardation layer transfer laminate side is irradiated with ultraviolet rays to adhere and wind up, and the circularly polarizing element transfer laminate having a length of 200 m ( Obtained a roll of CP1). In CP1, the thermoplastic resin base material of the PVA polarizer transfer laminate and the polyester film of the retardation layer transfer laminate 1 are peeled off immediately before transfer to the object (ITO layer).

(Example 2)
A paint for an orientation control layer was applied to the polarizer surface of the PVA polarizer transfer laminate and dried at 100 ° C. to provide an orientation control layer having a thickness of 0.5 μm. Further, the orientation control layer was treated with a rubbing roll wrapped with a brushed nylon cloth. The rubbing direction was 45 degrees with respect to the flow direction of the film. Subsequently, after applying the retardation layer coating material, the solvent was evaporated by heating at 110 ° C. for 3 minutes, and the rod-shaped liquid crystal compound was oriented. Further, it was irradiated with ultraviolet rays for 30 seconds in an environment of 110 ° C. to obtain a laminated body (CP2) for transferring a circularly polarized light element. The Re of the retardation layer was 140 nm.

(Example 3)
A 50 cm wide polyester film (Cosmo Shine (TM) A4100 manufactured by Toyobo Co., Ltd., 50 μm thick) is coated with a paint for an orientation control layer on the non-easy adhesive layer surface, dried at 100 ° C., and a 0.5 μm thick orientation control layer. Was provided. Further, the orientation control layer was treated with a rubbing roll wrapped with a nylon blanket. The rubbing direction was set to be the flow direction of the film. Then, a paint for a liquid crystal polarizer was applied to the rubbing treated surface and dried at 110 ° C. for 3 minutes to form a film having a thickness of 2 μm, which was then irradiated with ultraviolet rays to obtain a laminate for transferring a liquid crystal polarizer. Subsequently, an orientation control layer and a retardation layer are provided on the polarizer surface of this liquid crystal polarizer transfer laminate in the same manner as in Example 2, and the circular polarization element transfer laminate (CP3) is wound as a roll having a length of 200 m. I took it.

(Example 4)
After applying the hard coat layer paint to the non-easy adhesive layer surface of a polyester film with a width of 50 cm (Cosmo Shine (TM) A4100 manufactured by Toyo Boseki Co., Ltd., thickness 50 μm) and drying it in an oven at 90 ° C. to evaporate the solvent. A hard coat layer having a thickness of 3 μm was formed by irradiating with ultraviolet rays. Further, the hard coat layer was treated with a rubbing roll wrapped with a nylon blanket. The rubbing direction was parallel to the flow direction of the film. Then, in the same manner as in Example 3, a liquid crystal polarizer paint was applied to the rubbing treated surface to obtain a liquid crystal polarizer transfer laminate. A retardation layer was provided on the polarizer surface of the liquid crystal polarizer transfer laminate in the same manner as in Example 2, and the circular polarization element transfer laminate (CP4) was wound as a roll having a length of 200 m.

The configurations of Examples 1 to 4 are shown in Table 1.

(Example 5)
As the laminate for transfer of the retardation layer, it is carried out except that the non-easy adhesive layer surface of the polyester film is corona-treated and the retardation layer is provided on the corona-treated surface (laminator for transfer of the retardation layer 2). In the same manner as in Example 1, a roll of a laminated body (CP5) for transferring a circularly polarizing element having a length of 200 m was obtained. In CP5, the thermoplastic resin base material of the PVA polarizer transfer laminate is peeled off and used immediately before transfer to the object (glass substrate).

(Example 6)
A paint for an orientation control layer was applied to the retardation layer surface of the retardation layer transfer laminate 1 and dried at 100 ° C. to provide an orientation control layer having a thickness of 0.5 μm. Further, the orientation control layer was treated with a rubbing roll wrapped with a nylon blanket. The rubbing direction was set to be the flow direction of the film. Then, a liquid crystal polarizer paint is applied to the rubbing treated surface, dried at 110 ° C. for 3 minutes to form a film having a thickness of 2 μm, and then irradiated with ultraviolet rays to obtain a laminated body for transferring a circularly polarizing element (CP6). It was wound as a roll with a length of 200 m.

(Example 7)
The liquid crystal polarizer transfer laminate of Example 3 and the retardation layer transfer laminate 2 of Example 5 are unwound, and an ultraviolet curable adhesive is applied to the polarizer surface of the liquid crystal polarizer transfer laminate. After the adhesive surface and the retardation layer surface of the retardation layer transfer laminate 2 are overlapped, ultraviolet rays are irradiated from the retardation layer transfer laminate side to bond and wind up, and a circular polarizing element transfer having a length of 200 m is performed. A roll of laminated body (CP7) was obtained. In CP7, the polyester film of the liquid crystal polarizer transfer laminate is peeled off and used immediately before transfer to the object (glass substrate).

Table 2 shows the configurations of Examples 5 to 7.

Evaluation 1
The laminated body for transferring the circularly polarizing element (CP1) was unwound, cut out to a required size, and then the polyester film of the laminated body for transferring the retardation layer 1 was peeled off. An optical pressure-sensitive adhesive sheet is used to bond the ITO surface of a glass substrate on which ITO is laminated to the peeled surface (orientation control layer surface), and the obtained laminate is used as a thermoplastic resin base material for a PVA polarizer transfer laminate. (Releasable film) was peeled off. Subsequently, an optical adhesive sheet was attached to the peeled surface, and further, it was attached to the ITO surface of a transparent conductive polyester film having an ITO layer on one surface and a hard coat layer on the other surface, which were separately prepared. We made a model of a touch sensor equipped with a polarizing element. When the obtained touch sensor model was placed on the organic EL display device with the glass surface facing down and the antireflection effect was confirmed, the reflection of wiring etc. was reduced and the antireflection effect was high. It turned out.

When a model of a touch sensor equipped with a circular polarization element was similarly prepared and evaluated using the circular polarization element transfer laminates CP2 and CP3, it was found to have a high antireflection effect. In CP2 and CP3, the ITO surface of the glass substrate was bonded to the retardation layer surface using an optical adhesive sheet. Further, in CP3, when the transparent conductive polyester film was bonded to the ITO surface, the polyester film of the liquid crystal polarizer transfer laminate was peeled off instead of the thermoplastic resin base material of the PVA polarizer transfer laminate.

Evaluation 2
A model of a touch sensor was prepared in which the ITO surface of a glass substrate on which ITO was laminated and the ITO surface of a TAC film on which ITO was laminated were bonded with an optical adhesive.
The circular polarization element transfer laminate (CP4) was unwound, cut out to a required size, and then the polyester film of the retardation layer transfer laminate 1 was peeled off.
After bonding the retardation layer surface of CP4 to the TAC film surface of the touch sensor model using an optical adhesive, the polyester film of the liquid crystal polarizer transfer laminate is peeled off, and the touch sensor equipped with a circular polarizing element A model was created. When the obtained touch sensor model was placed on the organic EL display device with the glass surface facing down and the antireflection effect was confirmed, the reflection of wiring etc. was reduced and the antireflection effect was high. It turned out.

Evaluation 3
A touch sensor model in which the ITO surface of a glass substrate on which ITO is laminated and the ITO surface of a transparent conductive polyester film having an ITO layer on one surface and a hard coat layer on the other surface are bonded together with an optical adhesive. Prepared.
After unwinding the laminated body for transferring a circularly polarizing element (CP5) and cutting it into a required size, the thermoplastic resin base material of the laminated body for transferring a PVA polarizer was peeled off.
After bonding the polarizing element surface (PVA surface) of CP5 to the glass surface of the touch sensor model using an optical adhesive, the polyester film of the retardation layer transfer laminate was peeled off to provide a circular polarizing element. A model of the touch sensor was created. When the obtained touch sensor model was overlaid on the organic EL display device with the circular polarization element side down and the antireflection effect was confirmed, the reflection of wiring etc. was reduced and it had a high antireflection effect. It turned out that.

When a model of a touch sensor equipped with a circular polarization element was similarly prepared and evaluated using the circular polarization element transfer laminates CP6 and CP7, it was found to have a high antireflection effect. In CP6, the liquid crystal polarizer surface was attached to the glass surface of the touch sensor model using an optical adhesive sheet. In CP7, the polyester film of the liquid crystal polarizer transfer laminate was peeled off instead of the thermoplastic resin base material of the PVA polarizer transfer laminate when the touch sensor model was bonded to the glass surface.

In evaluations 1, 2 and 3, it was possible to incorporate the circular polarization element function into the touch sensor without significantly increasing the thickness.

Evaluation 4
The laminated body for transferring the circularly polarizing element (CP5) was unwound, cut out to a required size, and then the thermoplastic resin base material of the laminated body for transferring the PVA polarizer was peeled off. The polarizer surface and a polycarbonate sheet having a thickness of 1 mm were bonded together using an optical adhesive sheet to obtain a polycarbonate sheet in which circularly polarizing elements were laminated.
When the obtained polycarbonate sheet on which the circularly polarized light elements were laminated was placed on the organic EL display device with the circularly polarized light element side down and the antireflection effect was confirmed, the reflection of wiring etc. was reduced and the reflection was high. It was found to have a preventive effect.
The obtained polycarbonate sheet on which the circular polarization elements are laminated can be used as a surface cover sheet of an organic EL display device having an antireflection function with almost no increase in thickness.

Claims

A circle in which the polarizer and the λ / 4 retarder are laminated in this order on the releasable film, or the λ / 4 retardation layer and the polarizer are laminated in this order on the releasable film. Laminated body for transfer of polarizing element.
A method for manufacturing a transparent conductive base material having a circular polarization element.
(A) The λ / 4 retardation layer of the laminated body for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a releasable film on a transparent conductive substrate, is transparently conductive. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (B) the transparent conductive substrate has a λ / 4 retardation layer and a polarizer on the releasable film. A method comprising laminating the circularly polarizing element transfer laminate so that the polarizers of the circularly polarized element transfer laminates laminated in this order are arranged on the transparent conductive base material side.
A method for manufacturing a touch panel having a circularly polarized element.
(C) The λ / 4 retardation layer of a laminate for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a transparent conductive base material of a touch panel, is described above. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the transparent conductive base material side, or (D) λ / 4 phase difference on the releasable film on the transparent conductive base material of the touch panel. The step of laminating the circularly polarizing element transfer laminate is included so that the polarizer of the circular polarization element transfer laminate in which the layers and the polarizers are laminated in this order is arranged on the transparent conductive substrate side. ,Method.
A method for manufacturing an image display device having a circular polarization element.
A method comprising a step of providing the touch panel on an image display device so that a touch panel of a touch panel having a circular polarization element or a circular polarization element manufactured by the method of claim 3 is arranged on the visual side.
A method for manufacturing a transparent base material for a surface cover having a circular polarization element.
(E) The λ / 4 retardation layer of the multilayer body for transferring a circularly polarizing element, in which a polarizer and a λ / 4 retardation layer are laminated in this order on a releasable film on a transparent substrate for a surface cover, is transparent. The step of laminating the laminate for transferring the circularly polarizing element so as to be arranged on the substrate side, or (F) the transparent substrate for the surface cover, the λ / 4 retardation layer and the polarizer on the releasable film. A method including a step of laminating the circularly polarizing element transfer laminate so that the polarizer of the circularly polarized element transfer laminate laminated in this order is arranged on the transparent substrate side.
A method for manufacturing an image display device having a circular polarization element.
A step of providing the transparent base material in the image display device so that the transparent base material for the surface cover of the transparent base material for the surface cover having a circularly polarizing element produced by the method of claim 5 is arranged on the visual side. Including, method.