JP2017003963A - Laminate and image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate of a polarizer and a touch panel that suppresses curvature due to an influence of temperature or humidity, and an image display device comprising the laminate and an image display element.SOLUTION: There is provided a laminate 3 comprising a touch panel 1 and a polarizer 2 laminated on the touch panel 1 and formed in a coating method, where the polarizer is a dye-based polarizer including at least one thermotropic liquid crystalline dichromatic colorant.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate and an image display device.

In recent years, an image display device equipped with a touch panel and an organic electroluminescence (hereinafter abbreviated as “EL”) display element has been widely used.
The organic EL display element is known to reduce display quality when viewed outdoors, since external light is reflected inside the image display device, and suppresses reflection of external light using a circularly polarizing plate. Techniques have been proposed (see, for example, Patent Document 1).
Recently, a flexible organic EL display element has been proposed, and a touch panel mounted with the organic EL display element has also been developed having a flexible sheet shape.

On the other hand, as a circularly polarizing plate, a laminate of a linearly polarizing plate and a quarter wavelength plate is widely used.
In addition, a linear polarizing plate in which both sides of a polarizer formed by stretching a composite of polyvinyl alcohol and iodine are sandwiched by a pair of protective films is widely used.

JP 2012-32418 A

The present inventors examined using the polarizing plate which excluded the protective film of the single side | surface of a polarizer as a linearly-polarizing plate in a circularly-polarizing plate from a viewpoint of thickness reduction of a device.
As a result of the study, the present inventors have clarified that the polarizing plate from which the protective film on one side of the polarizer is omitted has a problem that it is bent by temperature or humidity because of its low self-supporting property. In particular, the present inventors show that a laminate in which a polarizing plate and a touch panel (in particular, a touch panel having flexibility) without a protective film on one side of a polarizer are bent in the manufacturing process depending on temperature or humidity. It has also been clarified that there is a problem that productivity decreases.

  In view of the above, an object of the present invention is to provide a laminate of a polarizer and a touch panel, which has a small degree of bending due to the influence of temperature or humidity, and an image display apparatus having the laminate and an image display element. .

The present inventors diligently studied to solve the above problems.
First, the present inventors paid attention to the fact that a polarizing plate without a protective film on one side of a polarizer always curves in the stretching direction when it is curved by temperature or humidity.
Here, the stretched film inevitably has anisotropy in internal stress, and further, there is anisotropy in the change of internal stress generated inside the film due to temperature change or humidity change.
And when the perturbation of temperature change or humidity change was given to the stretched film, the stretched film would swell or shrink in order to eliminate the change of the generated internal stress. Since there is anisotropy in the change of internal stress, anisotropy also occurs in the degree of swelling or shrinkage.
Here, in the case of a stretched film formed using a polymer as a main material, since the polymer main chain is generally aligned in the stretching direction, the stretched film is considered to swell or shrink significantly in the stretching direction. Moreover, the polarizer which has spread widely is a film formed by stretching a composite of polyvinyl alcohol and iodine.
For this reason, the inventors of the present invention have an essential cause that the polarizing plate is stretched due to temperature or humidity, and similarly, the touch panel (especially flexible) It was presumed that the laminated body laminated with the touch panel had a significant curvature due to temperature or humidity.
Therefore, if a laminate of a polarizer and a touch panel that has no anisotropy in the change of internal stress due to temperature change or humidity change can be developed, not only can productivity be improved, but also socially desired devices. It is thought that it can contribute to thinning.

As described above, since the stretched film has anisotropy in the change of internal stress caused by temperature change or humidity change inside the film, the present inventors use the stretched film as a polarizer. The idea is that if a polarizer formed by a coating method is laminated on a touch panel, a laminate of a polarizer and a touch panel with a small degree of bending due to the influence of temperature or humidity can be manufactured, and the present invention is completed. It came to.
That is, it has been found that the above-described problem can be achieved by the following configuration.

[1] A laminate having a touch panel and a polarizer laminated on the touch panel and formed by a coating method.
[2] The laminate according to [1], wherein the polarizer is a dye-based polarizer containing at least one thermotropic liquid crystalline dichroic dye.
[3] The laminate according to [1] or [2], in which the touch panel, the polarizer, and the optical film A having in-plane retardation are laminated in this order.
[4] The laminate according to [3], wherein the optical film A satisfies the following formula (I).
120 nm <Re (550) <160 nm Formula (I)
Here, in formula (I), Re (550) represents in-plane retardation at a wavelength of 550 nm.
[5] The laminate according to [3] or [4], wherein the optical film A satisfies the following formula (II).
Re (450) ≦ Re (550) ≦ Re (650) Formula (II)
Here, in formula (II), Re (450), Re (550), and Re (650) represent in-plane retardations at a wavelength of 450 nm, a wavelength of 550 nm, and a wavelength of 650 nm, respectively.
[6] The laminate according to any one of [3] to [5], wherein the optical film A is a film formed by a coating method.
[7] Lamination according to any of [3] to [6], in which a touch panel, a polarizer, an optical film A, and an optical film B having retardation in the thickness direction are laminated in this order. body.
[8] The laminate according to [7], wherein the optical film B satisfies the following formula (III).
−100 nm <Rth (550) <− 20 nm Formula (III)
Here, in Formula (III), Rth (550) represents retardation in the thickness direction at a wavelength of 550 nm.
[9] An image display device comprising the laminate according to any one of [1] to [8] and an image display element.
[10] The image display device according to [9], wherein the image display element is an organic EL display element.

  According to the present invention, the present invention provides a laminate of a polarizer and a touch panel, which has a small degree of bending due to the influence of temperature or humidity, and an image display device having the laminate and an image display element. Can do.

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of an image display device of the present invention.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
Moreover, in this specification, a polarizing plate refers to what a protective film or a functional layer has been arrange | positioned at the surface of at least one of a polarizer, and distinguishes and uses a polarizing plate and a polarizer.
Next, terms used in this specification will be described.

<Retardation>
In the present specification, “Re (λ)” and “Rth (λ)” represent in-plane retardation and retardation in the thickness direction at the wavelength λ, respectively.
Re (λ) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or KOBRA WR (both manufactured by Oji Scientific Instruments). In selecting the measurement wavelength λnm, the wavelength selection filter can be exchanged manually, or the measurement value can be converted by a program or the like.

Here, when the film to be measured is represented by a uniaxial or biaxial refractive index ellipsoid, Rth (λ) is calculated by the following method.
Rth (λ) is Re (λ) with the in-plane slow axis (determined by KOBRA 21ADH or KOBRA WR) as the tilt axis (rotation axis) (in the absence of the slow axis, With respect to the film normal direction (with an arbitrary direction as the rotation axis), the light of wavelength λ nm is incident from each inclined direction in steps of 10 degrees from the normal direction to 50 degrees on one side, and a total of 6 points are measured. The KOBRA 21ADH or KOBRA WR is calculated based on the measured retardation value, the assumed value of the average refractive index, and the input film thickness value.

In the above case, in the case of a film having a direction in which the retardation value is zero at a certain tilt angle with the in-plane slow axis from the normal direction as the rotation axis, retardation at a tilt angle larger than the tilt angle. The value is calculated in KOBRA 21ADH or KOBRA WR after changing its sign to negative.
In addition, the retardation value is measured from the two inclined directions, with the slow axis as the tilt axis (rotation axis) (when there is no slow axis, the arbitrary direction in the film plane is the rotation axis), Based on the value, the assumed value of the average refractive index, and the input film thickness value, Rth can also be calculated from the following formulas (1) and (2).

  In the formula, Re (θ) represents a retardation value in a direction inclined by an angle θ from the normal direction. Further, nx represents the refractive index in the slow axis direction in the plane, ny represents the refractive index in the direction perpendicular to nx in the plane, and nz represents the refractive index in the direction perpendicular to nx and ny. d represents the film thickness of the film.

In the case where the film to be measured cannot be expressed by a uniaxial or biaxial refractive index ellipsoid, that is, a film having no so-called optical axis (OPTIC AXIS), Rth (λ) is calculated by the following method.
Rth (λ) represents Re (λ) as an in-plane slow axis (determined by KOBRA 21ADH or KOBRA WR) as a tilt axis (rotation axis) from −50 degrees to +50 degrees with respect to the film normal direction. 11 points of light having a wavelength of λ nm are incident from each inclined direction in 10 degree steps until KOBRA 21ADH is measured based on the measured retardation value, assumed average refractive index, and input film thickness value. Or it is calculated by KOBRA WR.

  In the above measurement, as the assumed value of the average refractive index, the values in the polymer handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can be used. Those whose average refractive index is not known can be measured with an Abbe refractometer. The average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), Polystyrene (1.59). By inputting the assumed value of the average refractive index and the film thickness, nx, ny, and nz are calculated in KOBRA 21ADH or KOBRA WR. Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.

[Laminate]
The laminate of the present invention is a laminate having a touch panel and a polarizer laminated on the touch panel and formed by a coating method.
Hereinafter, the member used for the laminated body of this invention is demonstrated in detail.

[Touch panel]
The touch panel included in the laminate of the present invention is an input device that can input information corresponding to an instruction image by touching the instruction image displayed in the image display area of the image display device with a finger or a touch pen. means.
Examples of the touch panel system include a projected capacitive system, a surface capacitive system, and a resistive film system, but are not particularly limited in the present invention, and any type of touch panel is suitable. Can be used for

In the present invention, the member on the surface of the touch panel on which the polarizer described later is formed is preferably a flexible transparent member having an average transmittance of visible light (400 to 800 nm) of 80% or more. It can be used suitably.
Specific examples of the polymer film include, for example, cellulose acylate films (eg, cellulose triacetate film, cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film); polyolefins such as polyethylene and polypropylene Polyester film such as polyethylene terephthalate and polyethylene naphthalate; Polyether sulfone film; Polyacrylic resin film such as polymethyl methacrylate; Polyurethane resin film; Polycarbonate film; Polysulfone film; Polyether film; Pentene film; polyetherketone film; (meth) acrylonitrile film; Imide film; Polyamide film; Polymer film having an alicyclic structure (for example, norbornene resin film such as Arton (manufactured by JSR)); Amorphous polyolefin (for example, cycloolefin polymer such as Zeonex (manufactured by Nippon Zeon)) ) Film;

[Polarizer]
The polarizer of the laminate of the present invention is not particularly limited as long as it is formed by a coating method among so-called linear polarizers having a function of converting natural light into specific linearly polarized light.
In the present invention, an absorption polarizer and a reflection polarizer can be used, and it is preferable to use an absorption polarizer.

{Polarizer material}
The polarizer is not particularly limited as long as it can be formed by a coating method, and an iodine polarizer, a dye polarizer using a dichroic dye, a polyene polarizer, and the like can be used. Among these, a dye-based polarizer using a dichroic dye is preferably used.
As the dichroic dye, for example, International Publication No. 1997/007184, JP-A-10-095980, JP-A-10-279945, JP-A-11-080735, JP-A-11-172252, JP-A-2000-239664. JP, 2008-179670, JP 2009-007485, JP 2009-007486, JP 2010-155924, JP 2011-231245, JP 2012-031384, JP 2013-139521. Can be used.

In the present invention, it is preferable to use a dye-based polarizer using a thermotropic liquid crystalline dichroic dye from the viewpoint of facilitating the formation of the polarizer by a coating method.
A method for producing a dye-based polarizer using a thermotropic liquid crystalline dichroic dye is not particularly limited. For example, after forming an alignment film on a support (for example, a touch panel, a temporary support, etc.), the thermotropic liquid crystal It can be prepared by applying a composition containing a dichroic dye, an alignment agent, a leveling agent, other additives and a solvent.

<Thermotropic liquid crystalline dichroic dye>
As the thermotropic liquid crystalline dichroic dye, for example, a thermotropic liquid crystalline dichroic dye described in JP2011-237513A can be suitably used.

  Specific examples of the thermotropic liquid crystalline dichroic dye are shown below, but are not limited to these compounds.

<Orienting agent>
Examples of the aligning agent include compounds (horizontal aligning agents) represented by the general formulas (1) to (3) described in paragraphs [0253] to [0292] of JP2011-237513A. These contents are cited in the present specification.

<Leveling agent>
As the leveling agent, for example, a coating leveling agent such as a fluorine-based nonionic surfactant, a special acrylic resin leveling agent, or a silicone leveling agent can be used.

<solvent>
Specific examples of the solvent include ketones (eg, acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, etc.), ethers (eg, dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons. (For example, hexane), alicyclic hydrocarbons (for example, cyclohexane), aromatic hydrocarbons (for example, toluene, xylene, trimethylbenzene), halogenated carbons (for example, dichloromethane, dichloroethane, dichlorobenzene) , Chlorotoluene, etc.), esters (eg, methyl acetate, ethyl acetate, butyl acetate, etc.), water, alcohols (eg, ethanol, isopropanol, butanol, cyclohexanol, etc.), cellosolves (eg, methyl cellosolve, ethyl acetate) Sorbs), cellosolve acetates, sulfoxides (for example, dimethyl sulfoxide), amides (for example, dimethylformamide, dimethylacetamide, etc.), etc., and these may be used alone or in combination of two or more. You may use together.

{Polarizer formation method (coating method)}
A method of applying a coating liquid (hereinafter also referred to as “polarizer-forming coating liquid”) comprising a composition containing the thermotropic liquid crystalline dichroic dye described above is not particularly limited. For example, a spin coating method is used. In addition, known and commonly used methods such as gravure printing method, flexographic printing method, ink jet method, die coating method, slit die coating method, cap coating method, and dipping can be performed.

In the present invention, a polarizer (hereinafter also referred to as “polarizer with a temporary support”) formed by coating on a temporary support is directly or directly on the touch panel using an adhesive or an adhesive. The touch panel surfaces may be bonded after being chemically or physically treated.
When a polarizer with a temporary support is bonded to the touch panel, the polarizer may be bonded to the touch panel on the temporary support side, or may be bonded to the touch panel on the polarizer side.
When a polarizer with a temporary support is attached to the touch panel on the polarizer side, the temporary support may be peeled off and may remain as part of the panel layer structure. When the temporary support remains as part of the layer structure of the panel, the temporary support may function as an optical film described later or may not function.
Moreover, when applying the polarizer-forming coating solution on the temporary support, the temporary support is preferably a flexible transparent member having an average transmittance of visible light (400 to 800 nm) of 80% or more, A polymer film can be suitably used.
Specific examples of the polymer film include, for example, cellulose acylate films (eg, cellulose triacetate film, cellulose diacetate film, cellulose acetate butyrate film, cellulose acetate propionate film); polyolefins such as polyethylene and polypropylene Polyester film such as polyethylene terephthalate and polyethylene naphthalate; Polyether sulfone film; Polyacrylic resin film such as polymethyl methacrylate; Polyurethane resin film; Polycarbonate film; Polysulfone film; Polyether film; Pentene film; polyetherketone film; (meth) acrylonitrile film; Imide film; Polyamide film; Polymer film having an alicyclic structure (for example, norbornene resin film such as Arton (manufactured by JSR)); Amorphous polyolefin (for example, cycloolefin polymer such as Zeonex (manufactured by Nippon Zeon)) ) Film;

{Thickness of polarizer}
The thickness of the polarizer is not particularly limited, and the lower limit is preferably 250 nm or more, more preferably 350 nm or more, and further preferably 450 nm or more. About an upper limit, 50 micrometers or less are preferable, 30 micrometers or less are more preferable, and 20 micrometers or less are further more preferable. Moreover, when using a dye-type polarizer, 5 micrometers or less are preferable, 3 micrometers or less are more preferable, and 1 micrometer or less is further more preferable.

[Optical film A having in-plane retardation]
The laminate of the present invention has the above-mentioned touch panel, the above-described polarizer, and the optical film A having in-plane retardation for the purpose of suppressing external light incident from the touch panel side from being reflected inside the image display device. Are preferably laminated in this order.

The optical film A preferably has a λ / 4 plate function for converting linearly polarized light into circularly polarized light.
The optical film A may be a single layer having a λ / 4 plate function, or may have a plurality of layers having a λ / 4 plate function. Examples of the combination of multiple layers include a combination of a λ / 4 plate and a λ / 2 plate.

In consideration of the case where the polarizer has retardation or wavelength dispersion characteristics, the in-plane retardation of the optical film A does not have to be strictly λ / 4, and preferably satisfies the following formula (I).
120 nm <Re (550) <160 nm Formula (I)
Here, in formula (I), Re (550) represents in-plane retardation at a wavelength of 550 nm.

The optical film A preferably satisfies the following formula (II) for the purpose of suppressing a change in the color of reflected light.
Re (450) ≦ Re (550) ≦ Re (650) Formula (II)
Here, in formula (II), Re (450), Re (550), and Re (650) represent in-plane retardations at a wavelength of 450 nm, a wavelength of 550 nm, and a wavelength of 650 nm, respectively.

In recent years, there has been a strong demand for a thin layer of an image display device, and the optical film A can be formed by applying a material having a high refractive index anisotropy from the viewpoint of realizing a thin layer of a device. preferable.
As a material to be applied, a material that spontaneously develops optical anisotropy after coating is preferable, and a liquid crystalline compound can be particularly preferably used. The refractive index anisotropy at a wavelength of 550 nm of the material to be applied is preferably 0.01 or more, more preferably 0.03 or more, and further preferably 0.05 or more.
Further, the material to be applied may be applied as it is, or may be applied in a solution state after being dissolved in a solvent.
The material to be applied is applied directly or after the surface is chemically or physically treated on the surface of the polarizer or on the surface of the optical film B having retardation in the thickness direction described later. May be.
In addition, the material to be applied is formed on the temporary support by coating, and then has a retardation on the surface of the polarizer or in the thickness direction described later using an adhesive or an adhesive. You may transfer on the surface of the optical film B directly or after processing the surface chemically or physically.

  The lamination method when the optical film A is a plurality of layers is not particularly limited, for example, a method of laminating separately produced layers with an adhesive, a method of directly applying another layer to the previously produced layer, etc. Is mentioned.

[Optical film B having retardation in the thickness direction]
The laminate of the present invention has the above-mentioned touch panel, the above-described polarizer, the above-described optical film A, and the above-described touch panel for the purpose of favorably suppressing reflection of external light from directions other than the normal to the image display element surface. A laminated body in which the optical film B having retardation in the thickness direction is laminated in this order is preferable.

The optical film B preferably further satisfies the following formula (III) for the purpose of better suppressing reflection of external light from directions other than the normal to the surface of the image display element.
−100 nm <Rth (550) <− 20 nm Formula (III)
Here, in Formula (III), Rth (550) represents retardation in the thickness direction at a wavelength of 550 nm.

The optical film B may have a preferable retardation in the thickness direction as a single layer, or may have a preferable retardation in the thickness direction as a whole.
In addition, there are no particular limitations on the laminating method when the optical film B has a plurality of layers. For example, a method of laminating separately produced layers with an adhesive, or another layer is directly applied to the previously produced layer. Methods and the like.

{Optical film material}
The materials for the optical films A and B described above are not particularly limited, and may be a polymer film or a layer formed from a liquid crystalline compound.
From the viewpoint of reducing the thickness of the optical film, it is preferable to use a layer formed of a liquid crystalline compound.

<Liquid crystal compound>
The liquid crystalline compound is not particularly limited, and various known liquid crystalline compounds can be used according to the target optical characteristics.
The method for producing the layer formed from the liquid crystalline compound is not particularly limited. For example, a composition comprising an alignment film formed on a support and containing a liquid crystalline compound, an aligning agent, a leveling agent, other additives, a solvent, and the like. Can be applied. The liquid crystal compound in the composition may be one type or a plurality of types.

<Liquid crystal compound for optical film having in-plane retardation>
As the liquid crystal compound that can be used in producing the optical film A having in-plane retardation, any conventionally known liquid crystal compound may be used. For example, a general liquid crystal compound described in JP-A-2008-297210 may be used. Compounds represented by formula (I) (especially compounds described in paragraphs 0034 to 0039), compounds represented by general formula (1) described in JP 2010-84032 A (in particular, paragraphs 0067 to The compound described in 0073) may be used.
In particular, in combination with other liquid crystal compounds, azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, A rod-like liquid crystal compound selected from alkoxy-substituted phenylpyrimidines, phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles may be used.

As a particularly preferable example of the liquid crystalline compound that can be used in producing the optical film A having in-plane retardation, a compound represented by the following general formula (II) may be mentioned.
_{L 1 -G 1 -D 1 -Ar-} D 2 -G 2 -L 2 general formula (II)
In the formula, D ₁ and D ₂ are each independently —CO—O—, —O—CO—, —C (═S) O—, —O—C (═S) —, —CR ¹ R ^{2. -, - CR 1 R 2 -CR} 3 R 4 -, - O-CR 1 R 2 -, - CR 1 R 2 -O -, - CR 1 R 2 -O-CR 3 R 4 -, - CR 1 R ^2— O—CO—, —O—CO—CR ¹ R ² —, —CR ¹ R ² —O—CO—CR ³ R ⁴ —, —CR ¹ R ² —CO—O—CR ³ R ⁴ —, ^{-NR 1 -CR 2 R 3 -,} - CR 1 R 2 -NR 3 -, - CO-NR 1 -, or represents ^{-NR 1 -CO-, R 1, R} 2, R 3, and R ⁴ is Each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms, and G ₁ and G ₂ each independently represents a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms. , Methylene contained in the alicyclic hydrocarbon group The group may be substituted with —O—, —S—, —N (R ⁶ ) —, R ⁶ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and L ₁ and L ₂ are Each independently represents a monovalent organic group, at least one selected from the group consisting of L ₁ and L ₂ represents a monovalent group having a polymerizable group, and Ar represents the following general formula (II-1); Represents a divalent aromatic ring group represented by (II-2), (II-3), or (II-4):

In formulas (II-1) to (II-4), Q ₁ represents —S—, —O—, or NR ¹¹ —, and R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Y ₁ represents an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms, and Z ₁ , Z ₂ and Z ₃ are each independently a hydrogen atom Or an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR ¹² R ¹³ or SR ¹² , Z ₁ and Z ₂ may combine with each other to form an aromatic ring or an aromatic heterocyclic ring, and R ¹² and R ¹³ each independently represent a hydrogen atom or carbon represents the number 1-6 alkyl group, a ₁ and a ₂ each independently ^{is, -O -, - NR 21 -} (R 21 also represents a hydrogen atom Represents a substituent group), represents a group selected from the group consisting of —S— and CO—, X represents a hydrogen atom or a non-metal atom of Groups 14 to 16 to which a substituent group may be bonded, and Ax represents Represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and Ay is a carbon atom optionally having a hydrogen atom or a substituent. Represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an alkyl group of 1 to 6 or an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and Ax and Ay have The aromatic ring may have a substituent, Ax and Ay may be bonded to form a ring, and Q ₂ is a hydrogen atom or a carbon number that may have a substituent. 1-6 alkyl groups are represented.

For the definition and preferred range of each substituent of the compound represented by the general formula (II), D ¹ , D ² , G ¹ , G ² , L, and the like relating to the compound (A) described in JP2012-21068A ¹ , L ² , R ¹ , R ² , R ³ , R ⁴ , X ¹ , Y ¹ , Q ¹ , Q ² are respectively described as D ₁ , D ₂ , G ₁ , G ₂ , L ₁ , L ₂ , Reference can be made to R ¹ , R ² , R ³ , R ⁴ , X ¹ , and Y ¹ , Z ₁ , Z ₂ ,
JP A ₁ of the compound represented by formula (I) described in 2008-107767 JP, A _2, and the description of X respectively A _1, A _2, and X can refer for, in WO2013 / 018526 Ax of the compound represented by the general formula described (I), Ay, the description with respect to Q ¹ can refer Ax, Ay, for Q _2, respectively. Regarding Z ₃ , the description relating to Q ¹ relating to the compound (A) described in JP2012-21068A can be referred to.

In particular, the organic groups represented by L ₁ and L ₂ are each particularly preferably a group represented by —D ₃ —G ₃ —Sp—P ₃ . D ₃ is synonymous with D ₁ . G ₃ represents a single bond, a divalent aromatic or heterocyclic group having 6 to 12 carbon atoms, or a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms, and the above alicyclic hydrocarbon group The methylene group contained in may be substituted with —O—, —S—, or —NR ⁷ —, wherein R ⁷ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Sp is a single bond, — (CH ₂ ) _n —, — (CH ₂ ) _n —O—, — (CH ₂ —O—) _n —, — (CH ₂ CH ₂ —O—) _m , —O—. _{(CH 2) n -, -} O- (CH 2) n -O -, - O- (CH 2 -O-) n -, - O- (CH 2 CH 2 -O-) m, -C (= _{O) -O- (CH 2) n} -, - C (= O) -O- (CH 2) n -O -, - C (= O) -O- (CH 2 -O-) n -, - C (= O) -O- (CH 2 CH 2 -O-) m, -C (= O) -N (R 8) - (CH 2) n -, - C (= O) -N (R 8 _{) - (CH 2) n -O} -, - C (= O) -N (R 8) - (CH 2 -O-) n -, - C (= O) -N (R 8) - (CH 2 CH ₂ —O— represents a spacer group represented by _m . Here, n represents an integer of 2 to 12, m represents an integer of 2 to 6, and R ⁸ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. P ₃ represents a polymerizable group.

The polymerizable group is not particularly limited, but a polymerizable group capable of radical polymerization or cationic polymerization is preferable. As the radical polymerizable group, a generally known radical polymerizable group can be used, and preferable examples include acryloyl group and methacryloyl group. In this case, it is known that the acryloyl group is generally fast in the polymerization rate, and the acryloyl group is preferable from the viewpoint of productivity improvement, but the methacryloyl group is also used as the polymerizable group of the highly birefringent liquid crystal. be able to. As the cationic polymerizable group, generally known cationic polymerizable groups can be used. Specifically, the alicyclic ether group, the cyclic acetal group, the cyclic lactone group, the cyclic thioether group, the spiro orthoester group, the vinyloxy group, and the like. Examples include groups. Of these, alicyclic ether groups and vinyloxy groups are preferable, and epoxy groups, oxetanyl groups, and vinyloxy groups are particularly preferable.
Examples of particularly preferred polymerizable groups include the following.

In the present specification, the “alkyl group” may be any of linear, branched, or cyclic. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, 1,1-dimethyl A propyl group, n-hexyl group, isohexyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group and the like can be mentioned.
Although a preferable example is shown below as a compound represented by general formula (II), it is not specifically limited to these.

<Liquid crystal compound for optical film having retardation in thickness direction>
As the liquid crystalline compound that can be used in producing the optical film B having retardation in the thickness direction, a rod-like liquid crystalline compound is preferable.
The liquid crystal compound is preferably a liquid crystal compound exhibiting a smectic phase or a nematic phase liquid crystal state, and more preferably a liquid crystal compound exhibiting a nematic phase liquid crystal state.
As the liquid crystalline compound that can be used when producing the optical film B having retardation in the thickness direction, the liquid crystalline compound that can be used when producing the optical film A having in-plane retardation described above and A similar liquid crystal compound can be used, but a compound represented by the following general formula (IA) or a compound represented by the following general formula (IIA) can also be used.

In General Formula (IA) and General Formula (IIA), R ^{101 to} R ¹⁰⁴ are each independently — (CH ₂ ) _n —OOC—CH═CH ₂ , and n represents an integer of 2 to 8. X ₁₀₁ and Y ₁₀₁ each independently represent a hydrogen atom or a methyl group.
From the viewpoint of suppressing crystal precipitation, in the general formula (IA) or (IIA), X and Y preferably represent a methyl group. From the viewpoint of exhibiting properties as a liquid crystal, n is preferably an integer of 4 to 8.

[Image display device]
The image display apparatus of this invention has the laminated body which has the polarizer and touch panel of this invention, and an image display element.

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of an image display device of the present invention.
As shown in FIG. 1, the image display device 10 includes a laminate 3 having a touch panel 1 and a polarizer 2, and an image display element 4.
In this invention, you may have another member between each member.

The image display element used in the present invention is not particularly limited, and various known elements such as a liquid crystal display element and an organic EL display element can be used.
Among these, the organic EL display element is preferable because it has a high original reflectance and a large effect according to the present invention.

  Hereinafter, the present invention will be specifically described based on examples. The materials, reagents, amounts and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the present invention is not limited to the following examples.

[Example 1]
<Production of touch panel 1>
In Example 101 of JP 2014-10814 A, the same as Example 101 except that a commercially available polymethyl methacrylate film having a thickness of 50 μm was used as the transparent substrate (front plate) instead of a glass transparent substrate. A capacitive input device (hereinafter referred to as “touch panel 1”) was produced by the method described above.

<Surface Treatment of Touch Panel 1: Formation of Alignment Film 1a>
An alignment film 1a was formed on the surface of the touch panel 1 on the polymethyl methacrylate film side using a coating liquid for forming an alignment film 1 having the following composition, and the surface of the alignment film 1a was further rubbed.
―――――――――――――――――――――――――――――――――
Composition of coating solution for alignment film 1 formation ―――――――――――――――――――――――――――――――――
Modified polyvinyl alcohol below 2.4 parts by weight Isopropyl alcohol 1.6 parts by weight Methanol 36 parts by weight Water 60 parts by weight ―――――――――――――――――――――――――― ―――――――

<Production of Polarizer 1: Production of Laminate of Touch Panel 1 and Polarizer 1>
A dye polarizer coating solution 1 having the following composition was prepared.
―――――――――――――――――――――――――――――――――
Composition of Dye Polarizer Coating Solution 1 ――――――――――――――――――――――――――――――――――
Dichroic dye PB-7 50 parts by mass Dichroic dye C-3 30 parts by mass Dichroic dye C-19 20 parts by mass The following fluorine-containing compound C 0.3 parts by mass Chloroform 1130 parts by mass ―――――――――――――――――――――――――――

Fluorine-containing compound C

On the surface of the alignment film 1a subjected to the rubbing treatment, the dye polarizer coating solution 1 was cast for 10 seconds at 2000 rpm using a spin coater.
Next, after aging for 15 seconds while maintaining the temperature of the coating film at 160 ° C., the film was cooled to room temperature, and a polarizer 1 was formed on the touch panel 1. The formed polarizer 1 had an absorption axis oriented parallel to the rubbing direction.
By the above procedure, a laminate of the touch panel 1 and the polarizer 1 (hereinafter referred to as “touch panel 1 with a polarizer”) was produced.

[Example 2]
<Surface Treatment of Polarizer 1: Formation of Alignment Film 1b>
The alignment film 1b was formed on the surface of the polarizer 1 touch panel 1 manufactured in Example 1 on the side of the polarizer 1 using the above-described coating liquid for forming the alignment film 1. Further, the surface of the alignment film 1b was rubbed in a direction of 45 ° with respect to the rubbing direction applied to the surface of the alignment film 1a.

<Production of A plate 1: Production of a laminate of the touch panel 1 with a polarizer and the A plate 1>
A coating solution 1 for A plate having the following composition for forming an optical film having in-plane retardation (hereinafter referred to as “A plate”) was prepared.
―――――――――――――――――――――――――――――――――
Composition of coating liquid 1 for A plate ―――――――――――――――――――――――――――――――――
The following reverse wavelength dispersion liquid crystalline compound R-3 100 parts by mass photopolymerization initiator (Irgacure 819, manufactured by BASF Corp.) 3.0 parts by mass The following fluorine-containing compound A 0.8 parts by mass The following crosslinkable polymer O-2 0 .3 parts by mass chloroform 588 parts by mass ――――――――――――――――――――――――――――――――――

On the surface of the alignment film 1b subjected to the rubbing treatment, the coating liquid 1 for A plate was applied using a bar coater.
Next, after aging for 60 seconds while maintaining the temperature of the coating film at 100 ° C., the coating film was cooled to 70 ° C. and air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 70 mW / cm ² under air. The A plate 1 was formed by fixing the alignment state by irradiating with 1000 mJ / cm ² of ultraviolet rays.
By the above procedure, a laminate (hereinafter referred to as “touch panel 1 with a circularly polarizing plate”) in which the A plate 1 was formed on the polarizer 1 side of the touch panel with polarizer 1 produced in Example 1 was produced.

The retardation of the A plate 1 in the touch panel 1 with a circularly polarizing plate was measured as follows.
The alignment film 1b was formed on the glass substrate surface by the same method except that the touch panel 1 was changed to a commercially available glass substrate, and a rubbing treatment was performed. Next, an A plate 1 was produced on the alignment film 1b using the A plate coating solution 1 in the same manner as in Example 2.
Using the A plate 1 produced on the surface of the glass substrate as a specimen, the retardation of the A plate 1 in the touch panel 1 with a circularly polarizing plate was measured. When the phase difference was measured using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments), Re at a wavelength of 450 nm, a wavelength of 550 nm, and a wavelength of 650 nm was 108 nm, 130 nm, and 137 nm, respectively. It was. Rth at a wavelength of 550 nm was 65 nm.

[Example 3]
<Preparation of temporary support with alignment film 2>
An alignment film 2 is formed on the surface of a commercially available PET (polyethylene terephthalate) film using a coating liquid for forming an alignment film 2 having the following composition, and a temporary support with an alignment film 2 using PET as a temporary support is produced. did.
―――――――――――――――――――――――――――――――――
Composition of coating solution for alignment film 2 formation ―――――――――――――――――――――――――――――――――
Polyvinyl alcohol PVA103 (manufactured by Kuraray Co., Ltd.) 2.4 parts by mass Isopropyl alcohol 1.6 parts by mass Methanol 36 parts by mass Water 60 parts by mass ―――――――――――――――――――――― ―――――――――――

<Preparation of C plate 1>
A C-plate coating solution 1 having the following composition for forming an optical film having retardation in the thickness direction (hereinafter referred to as “C-plate”) was prepared.
―――――――――――――――――――――――――――――――――
Composition of coating liquid 1 for C plate ―――――――――――――――――――――――――――――――――
80 parts by mass of the following liquid crystal compound B01 20 parts by mass of the following liquid crystal compound B02 1 part by mass of the following vertical alignment agent S01 0.5 part by mass of the vertical alignment agent S02 0.5 parts by mass of ethylene oxide modified trimethylolpropane triacrylate (V # 360, Osaka Organic Chemistry) 8 parts by mass Irgacure 907 (manufactured by BASF) 3 parts by mass Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 1 part by mass The following fluorine-containing compound B03 0.4 part by mass methyl ethyl ketone 170 parts by mass cyclohexanone 30 parts by mass ―――――――――――――――――――――――――――――――――

The coating liquid 1 for C plate was apply | coated on the surface of the alignment film 2 of the temporary support body with the alignment film 2 produced above using the bar coater.
Next, after aging for 60 seconds while maintaining the temperature of the coating film at 60 ° C., ultraviolet rays of 1000 mJ / cm ² using an air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) of 70 mW / cm ² under air. The C plate 1 was formed by fixing the orientation state, and a temporary support with the C plate 1 was produced.

<Lamination of C plate 1>
The C plate 1 side of the temporary support with the C plate 1 was bonded to the side of the A plate 1 of the touch panel 1 with a circularly polarizing plate produced in Example 2 using an adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.). The temporary support body was peeled after bonding, and the laminated body (henceforth "the touch panel 2 with a circularly-polarizing plate") of the touchscreen 1 with a circularly-polarizing plate and C plate 1 was produced.

The retardation of the C plate 1 on the touch panel 2 with a circularly polarizing plate was measured as follows.
The alignment film 2 was formed on the glass substrate surface in the same manner as in Example 3 except that the surface of the PET film was changed to the surface of a commercially available glass substrate. Further, the C plate 1 was formed on the surface of the alignment film 2 using the C plate coating solution 1 in the same manner as in Example 3.
Retardation of the C plate 1 in the touch panel 2 with a circularly polarizing plate was measured using the C plate 1 produced on the glass substrate surface as a specimen. When the phase difference was measured using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments), Re was 0 nm and Rth was −60 nm at a wavelength of 550 nm.

[Comparative Example 1]
<Preparation of Polarizing Plate 1>
{Preparation of polarizer 2}
A roll-shaped polyvinyl alcohol film having a thickness of 80 μm was continuously stretched 5 times in the conveying direction in an aqueous iodine solution and dried to obtain a polarizer 2 having a thickness of 20 μm.

{Preparation of protective film}
The surface of the cellulose triacetate film (TD80UL, manufactured by Fuji Film) was subjected to alkali saponification treatment to produce a protective film.
In the alkali saponification treatment, a cellulose triacetate film is first immersed in an aqueous 1.5 N sodium hydroxide solution at 55 ° C. for 2 minutes and then washed in a water bath at room temperature, and 0.1 N sulfuric acid at 30 ° C. is used. Neutralized. Then, it was washed again in a room temperature water bath and further dried with hot air at 100 ° C.

{Lamination of polarizer 2 and protective film}
The alkali saponification surface of the cellulose triacetate film was bonded to one side of the polarizer 2. For pasting, an aqueous polyvinyl alcohol adhesive solution was used.
By the above procedure, a polarizing plate 1 in which a protective film was bonded to one side of the polarizer 2 was produced.

<Preparation of Laminate of Touch Panel 1 and Polarizer 2>
The protective film side of the polarizing plate 1 was bonded to the polymethyl methacrylate film side of the touch panel 1 produced using an adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.). By this procedure, a laminate of the touch panel 1 and the polarizer 2 (hereinafter referred to as “touch panel 2 with a polarizer”) was produced.

[Comparative Example 2]
<Surface treatment of polarizer 2>
The surface of the polarizer 2 of the touch panel 2 with a polarizer produced in Comparative Example 1 was rubbed in a direction of 45 ° with respect to the extending direction of the polarizer 2.

<Preparation of A plate 1>
The A plate 1 was formed by applying the A plate coating solution 1 to the surface of the polarizer 2 subjected to the rubbing treatment of the polarizer touch panel 2 in the same manner as in Example 2.
By the above procedure, a laminate (hereinafter referred to as “touch panel 3 with a circularly polarizing plate”) in which the A plate 1 was formed on the polarizer 2 side of the touch panel 2 with a polarizer was produced.
The touch panel 3 with a circularly polarizing plate was curved in the aging process for forming the A plate 1.

[Comparative Example 3]
<Preparation of C plate 1>
C plate of temporary support with C plate 1 produced in Example 3 using adhesive (SK2057, manufactured by Soken Chemical Co., Ltd.) on the side of A plate 1 of touch panel 3 with circularly polarizing plate produced in Comparative Example 2 One side was bonded. The temporary support body was peeled after bonding, and the laminated body (henceforth "the touchscreen 4 with a circularly-polarizing plate") of the touchscreen 3 with a circularly-polarizing plate and C plate 1 was produced.
Since the touch panel 3 with a circularly polarizing plate was curved, the touch panel 4 with a circularly polarizing plate was also curved to the same extent.

[An endurance test]
Durability tests (heat resistance test and moisture resistance test) of the touch panels 1 and 2 with a polarizer and the touch panels 1 and 2 with a circularly polarizing plate were performed. The results are shown in Table 1 below.
In addition, since the touch panels 3 and 4 with a circularly polarizing plate produced in Comparative Examples 2 and 3 were already curved when the production was completed, the durability test was not performed.

<Heat resistance test>
The touch panel 1 and 2 with a 5 cm square polarizer and the touch panel 1 and 2 with the same size circular polarizing plate are placed in an environment having a temperature of 25 ° C. and a volumetric absolute humidity of 11.5 g / m ³ (relative humidity of 50%). After standing for a period of time, the degree of bending after further placing in an environment at a temperature of 60 ° C. and a volumetric absolute humidity of 11.7 g / m ³ (relative humidity 9%) was measured.
The degree of bending was measured by placing the sample on a horizontal table so that the bending direction was the upper surface, and measuring the maximum value of the height of the curved part floating from the horizontal table.
The evaluation criteria were A for less than 1 mm, B for 1 mm or more and less than 5 mm, and C for 5 mm or more.

<Moisture resistance test>
A sample of touch panel 1 and 2 with a 5 cm square polarizer and touch panel 1 and 2 with the same size circular polarizer is placed in an environment with a temperature of 25 ° C. and a volumetric absolute humidity of 11.5 g / m ³ (relative humidity of 50%). After being left for a period of time, the degree of curvature after further 24 hours in an environment of a temperature of 25 ° C. and a volumetric absolute humidity of 2.3 g / m ³ (relative humidity of 10%) was measured. The measurement of the degree of bending and the evaluation criteria are in accordance with the heat resistance test.

From the results shown in Table 1, the touch panel 1 with a polarizer and the touch panels 1 and 2 with a polarizing plate both have an evaluation result of A heat resistance test and a humidity resistance test, and the degree of bending due to the influence of temperature or humidity is small. (Examples 1-3).
On the other hand, as for the touch panel 2 with a polarizer, the evaluation results of the heat resistance test and the moisture resistance test are both C, and it was found that the degree of bending due to the influence of temperature or humidity is large (Comparative Example 1). Moreover, since the touchscreens 3 and 4 with a polarizing plate were curved 5 mm or more before implementing an endurance test, it is thought that the degree of curvature by the influence of temperature or humidity is large (Comparative Examples 2-3).
From the above results, it was found that the touch panel with a polarizer and the touch panel with a circularly polarizing plate manufactured by laminating the polarizers produced by the coating process have a small degree of curvature due to the influence of temperature or humidity. .

[Mounting on organic EL display elements and evaluation of reflected light]
Disassemble the GALAXY S4 manufactured by SAMSUNG equipped with an organic EL display element, peel the used circularly polarizing plate and the touch panel, and use the circularly polarizing plate touch panels 1 and 2 prepared in Examples 2 and 3 as pressure-sensitive adhesives. The organic EL image display device was produced by pasting each of the materials. It was confirmed that any touch panel with a circularly polarizing plate functions well as an antireflection plate.

DESCRIPTION OF SYMBOLS 1 Touch panel 2 Polarizer 3 Laminated body 4 Image display element 10 Image display apparatus

Claims (10)

  A laminate having a touch panel and a polarizer laminated on the touch panel and formed by a coating method.   The laminate according to claim 1, wherein the polarizer is a dye-based polarizer containing at least one thermotropic liquid crystalline dichroic dye.   The laminate according to claim 1 or 2, wherein the touch panel, the polarizer, and the optical film A having in-plane retardation are laminated in this order. The laminate according to claim 3, wherein the optical film A satisfies the following formula (I).
120 nm <Re (550) <160 nm Formula (I)
Here, in the formula (I), Re (550) represents in-plane retardation at a wavelength of 550 nm. The laminate according to claim 3 or 4, wherein the optical film A satisfies the following formula (II).
Re (450) ≦ Re (550) ≦ Re (650) Formula (II)
Here, in the formula (II), Re (450), Re (550), and Re (650) represent in-plane retardation at a wavelength of 450 nm, a wavelength of 550 nm, and a wavelength of 650 nm, respectively.   The laminate according to any one of claims 3 to 5, wherein the optical film A is a film formed by a coating method.   The lamination according to any one of claims 3 to 6, wherein the touch panel, the polarizer, the optical film A, and the optical film B having retardation in the thickness direction are laminated in this order. body. The laminate according to claim 7, wherein the optical film B satisfies the following formula (III).
−100 nm <Rth (550) <− 20 nm Formula (III)
Here, in the formula (III), Rth (550) represents retardation in the thickness direction at a wavelength of 550 nm.   The image display apparatus which has a laminated body of any one of Claims 1-8, and an image display element.   The image display device according to claim 9, wherein the image display element is an organic electroluminescence display element.