JP7328000B2 - Long laminate and organic EL display device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a long laminate and an organic EL display device.

An elliptically polarizing plate is an optical member in which a polarizing plate and a retardation plate are laminated. is used to prevent In order to suppress light leakage in the oblique direction in this elliptically polarizing plate, Patent Document 1 describes an optical film provided with optical compensation properties by combining two retardation plates each made of a horizontally aligned liquid crystal cured film. .

JP 2015-163938 A

However, an optical film manufactured using two horizontally aligned liquid crystal cured films as a retardation plate is generally manufactured by independently preparing each horizontally aligned liquid crystal cured film and then bonding the two together. There are many things. In addition, even when two horizontally aligned liquid crystal cured films are formed continuously, it is necessary to repeat the coating process of the composition for forming each horizontal liquid crystal cured film, which tends to complicate the manufacturing process. There is a problem that productivity tends to decrease.
In addition, in recent years, there is a continuous demand for thinner displays such as image display panels, and there is a demand for further thinning of retardation plates and elliptically polarizing plates, which are one of the components. It is

INDUSTRIAL APPLICABILITY The present invention can be manufactured more easily and with high productivity, and when incorporated as one member constituting an elliptically polarizing plate, it is possible to reduce the thickness of the polarizer by omitting the protective layer on one side of the polarizer. It is an object of the present invention to provide a long laminate that can obtain a retardation plate that has a high effect of suppressing light leakage and has a small change in front color hue.

The present invention provides the following preferred aspects.
[1] A long laminate having a first retardation layer, a photo-alignment film, and a second retardation layer in this order,
A long laminate satisfying the following formulas (1) and (2), wherein one of the first retardation layer and the second retardation layer is a stretched film and the other is a liquid crystal cured film.
10°≦θa≦30° or 60°≦θa≦80° (1)
2θa+40°≦θb≦2θa+50° (2)
[In the formula, θa is the smaller of the angles formed by the longitudinal direction of the long laminate and the slow axis of the first retardation layer, and θb is the longitudinal direction of the first retardation layer and the It is the smaller of the angles formed by the slow axes of the two retardation layers. ]
[2] The long laminate according to [1] above, wherein the first retardation layer satisfies the following formula (3) and the second retardation layer satisfies the following formula (4).
200nm<Re(550)<320nm (3)
100nm<Re(550)<160nm (4)
[In the formula, Re(550) represents an in-plane retardation value at a wavelength of 550 nm. ]
[3] The long laminate according to [1] or [2], wherein the photoreactive group of the photo-alignment film is a dimerization-reactive photoreactive group.
[4] The long laminate according to any one of [1] to [3], wherein the photo-alignment film has a number average molecular weight of 20,000 to 100,000.
[5] The long laminate according to any one of [1] to [4], wherein the photo-alignment film has a thickness of 100 to 300 nm.
[6] having a transparent protective layer, an adhesive layer, a polarizing layer, an adhesive layer, a first retardation layer, a photo-alignment film and a second retardation layer in this order;
The long laminate according to any one of [1] to [5], wherein the first retardation layer is a stretched film and the second retardation layer is a cured liquid crystal film.
[7] The long laminate according to [6] above, wherein the total light transmittance at 380 nm of the transparent protective layer is 30% or less.
[8] The long laminate according to the above [6] or [7], wherein the polarizing layer contains iodine as the dichroic dye, and the absorption axis of the polarizing layer is the longitudinal direction of the long laminate. body.
[9] An organic EL display device comprising a sheet obtained from the long laminate according to any one of [1] to [8].

According to the present invention, it can be manufactured more easily and with good productivity, and when incorporated as a member constituting an elliptically polarizing plate, it is possible to reduce the thickness by omitting the protective layer on one side of the polarizer. In addition, it is possible to provide a long laminate from which a retardation plate having a high suppressing effect on light leakage and a small frontal hue change can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows an example of the layer structure of the long laminated body of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic sectional drawing which shows an example of the layer structure of the long laminated body of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. It should be noted that the scope of the present invention is not limited to the embodiments described here, and various modifications can be made without departing from the gist of the present invention.

The long laminate of the present invention has a first retardation layer and a second retardation layer in this order, and a photo-alignment film is provided between the first retardation layer and the second retardation layer. have. An example of the layer structure of the long laminate of the present invention will be described below with reference to FIG. 1, but the laminate of the present invention is not limited to these embodiments.

FIG. 1 is a diagram showing a cross section of the long laminate of the present invention cut in the thickness direction. A long laminated body 11 of the present invention is formed by laminating a first retardation layer 1, a photo-alignment film 3 and a second retardation layer 2 in this order. In the layer structure of the long laminate 11 shown in FIG. 1, the photo-alignment film 3 is formed directly on the first retardation layer 1, and the first retardation layer 1 and the photo-alignment film 3 are adjacent to each other. exist as Further, in the layer structure of the long laminate 11 shown in FIG. 1, the second retardation layer 2 is formed directly on the photo-alignment film 3, and the photo-alignment film 3 and the second retardation layer 2 are adjacent to each other. Between the first retardation layer 1, the photo-alignment film 3, and the second retardation layer 2, as long as it does not affect the effect of the present invention, for example, an adhesive layer, a protective layer, etc. layer may be included, but by thinning the laminate, the effect of suppressing the frontal hue change and the flexibility when incorporated in the elliptically polarizing plate can be further improved, so the first retardation The layer 1, the photo-alignment film 3 and the second retardation layer 2 are preferably present adjacent to each other in this order.

In the long laminate of the present invention, one of the first retardation layer and the second retardation layer is a stretched film, and the other is a liquid crystal cured film, satisfying the following formulas (1) and (2). .
10°≦θa≦30° or 60°≦θa≦80° (1)
2θa+40°≦θb≦2θa+50° (2)
In formulas (1) and (2), θa is the smaller angle between the longitudinal direction of the long laminate and the slow axis of the first retardation layer, and θb is the first retardation layer. and the slow axis of the second retardation layer.

The long layered product of the present invention may be formed by laminating a retardation layer which is a stretched film and a retardation layer which is a liquid crystal cured film. When the long laminate of the present invention further includes a polarizing layer, a retardation layer made of a stretched film can also function as a protective layer for the polarizing layer, so a protective layer is provided on one side of the polarizing layer (polarizer). The retardation layer can be laminated without Therefore, in such a case, the retardation layer laminated on the polarizing layer via an adhesive layer is a stretched film, and the retardation layer laminated on the side opposite to the polarizing layer of the retardation layer is a liquid crystal cured film. is preferred.

In the long laminate of the present invention, the smaller angle (θa) of the angles formed by the slow axis of the first retardation layer with respect to the long axis direction of the long laminate is 10° to 30°. or 60 ° to 80 °, and the smaller angle (θb) of the angles formed by the longitudinal direction of the first retardation layer and the slow axis of the second retardation layer is in the range of 2θa + 40 ° to 2θa + 50 ° It is in. By laminating the first retardation layer and the second retardation layer so as to satisfy the above relationship, that is, the formulas (1) and (2), the long laminate of the present invention is an elliptically polarized light When incorporated as a member constituting a plate, the retardation plate can have a high effect of suppressing light leakage and a small change in front hue.

From the viewpoint of easily obtaining a retardation plate exhibiting excellent optical properties and having a high effect of suppressing light leakage and hue change, the value of θa is preferably 13° to 27° or 63° to 77°, more preferably. ranges from 15° to 25° or from 65° to 75°. The value of θb is preferably in the range of 2θa+42° to 2θa+48°, more preferably 2θa+44° to 2θa+46°.

In the long laminate of the present invention, the slow axis of the first retardation layer is represented by the formula On the first retardation layer that is at a specific angle that satisfies (1) and produces a slow axis in the above relationship with respect to the long laminate, the longitudinal direction of the first retardation layer (that is, , which is also the longitudinal direction of the second retardation layer). The long laminate of the present invention having such a configuration is, for example, a polymerizable material for forming a second retardation layer on the stretched film while conveying a long stretched film as the first retardation layer. Continuous production is possible by applying a polymerizable liquid crystal composition containing a liquid crystal compound and curing the polymerizable liquid crystal compound in an aligned state. Furthermore, for example, when forming an elliptically polarizing plate by laminating a polarizing film containing a polarizing layer, a long polarizing film wound into a roll is subjected to the so-called Roll to Roll method, the first retardation layer of the present invention. and the second retardation layer. Thereby, for example, it is possible to continuously produce a final product such as an elliptical polarizing plate using a commercially available general polarizing film roll, which is easier and more productive. can be manufactured.

In the long laminate of the present invention, it is preferable that the first retardation layer satisfies the following formula (3) and the second retardation layer satisfies the following formula (4).
200nm<Re(550)<320nm (3)
100nm<Re(550)<160nm (4)
[In the formula, Re(550) represents an in-plane retardation value at a wavelength of 550 nm. ]
When the first retardation layer has optical properties satisfying formula (3) and the second retardation layer has optical properties satisfying formula (4), the first retardation layer and the second The long laminate of the present invention, which is obtained by laminating two retardation layers, has a higher effect of suppressing light leakage and frontal hue change when incorporated as an elliptically polarizing plate, and has excellent optical characteristics. become a board.

In the present invention, the first retardation plate more preferably has optical properties satisfying formula (5), more preferably formula (6).
180nm<Re(550)<300nm (5)
200nm<Re(550)<280nm (6)
Also, the second retardation plate more preferably has optical properties satisfying formula (7), more preferably formula (8).
110nm<Re(550)<150nm (7)
130nm<Re(550)<145nm (8)

Both the first retardation layer and the second retardation layer preferably have optical properties represented by formula (9), and have optical properties represented by formulas (9) and (10) is more preferable.
Re(450)/Re(550)≧1.00 (9)
1.00≧Re(650)/Re(550) (10)
[In the formula, Re(λ) represents an in-plane retardation value at a wavelength of λnm. ]

The in-plane retardation value can be adjusted by the thickness d of the first retardation layer and the second retardation layer. Since the in-plane retardation value is determined by Re (λ) = (nx (λ) - ny (λ)) x d, the desired in-plane retardation value (Re (λ): wavelength λ (nm) In order to obtain the in-plane retardation value of each retardation layer in , the three-dimensional refractive index and the film thickness d should be adjusted. In the above formula, d represents the thickness of the target retardation layer, and nx is the principal refraction at the wavelength λ nm in the direction parallel to the plane of the retardation layer in the refractive index ellipsoid formed by the retardation layer. and ny is the refractive index at a wavelength λnm in a direction parallel to the plane of the retardation layer and perpendicular to the nx direction in the refractive index ellipsoid formed by the retardation layer. represent.

By combining the first retardation layer and the second retardation layer having the optical properties represented by formula (9) and / or formula (10), uniform polarization in a wide wavelength range of visible light A long laminate (retardation plate) exhibiting conversion performance can be obtained.

In the present invention, either one of the first retardation layer and the second retardation layer is a retardation layer formed of a stretched film. A stretched film is usually obtained by stretching a substrate. As the base material, a transparent base material capable of transmitting light, particularly visible light, is preferable, and a material having a transmittance of 80% or more with respect to light having a wavelength of 380 to 780 nm is preferable. Examples of transparent substrates include substrates formed from translucent resins. Translucent resins that form the substrate include polyolefins such as polyethylene and polypropylene; cyclic olefin resins such as norbornene polymers; polyvinyl alcohol; polyethylene terephthalate; cellulose, cellulose esters such as cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyethersulfone; polyetherketone; From the viewpoint of availability and transparency, polyethylene terephthalate, polymethacrylate, cellulose ester, cyclic olefin resin, or polycarbonate are preferred.

Cellulose ester is obtained by esterifying some or all of the hydroxyl groups contained in cellulose, and is commercially available. Cellulose ester substrates are also commercially available. Examples of commercially available cellulose ester substrates include "Fujitac (registered trademark) film" (Fuji Photo Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (Konica Minolta Opto Co., Ltd.). be done.

Polymethacrylic acid esters and polyacrylic acid esters (hereinafter, polymethacrylic acid esters and polyacrylic acid esters are also collectively referred to as "(meth)acrylic resins") can be obtained from the market.

(Meth)acrylic resins include, for example, homopolymers of methacrylic acid alkyl esters or acrylic acid alkyl esters, and copolymers of methacrylic acid alkyl esters and acrylic acid alkyl esters. Specific examples of methacrylic acid alkyl esters include methyl methacrylate, ethyl methacrylate and propyl methacrylate, and specific examples of acrylic acid alkyl esters include methyl acrylate, ethyl acrylate and propyl acrylate. Commercially available general-purpose (meth)acrylic resins can be used as such (meth)acrylic resins. As the (meth)acrylic resin, an impact-resistant grade (meth)acrylic resin may be used.

In order to improve the mechanical strength of the stretched film, the (meth)acrylic resin may contain rubber particles. Acrylic rubber particles are preferable as the rubber particles. Here, the acrylic rubber particles have rubber elasticity obtained by polymerizing an acrylic monomer containing an acrylic acid alkyl ester such as butyl acrylate or 2-ethylhexyl acrylate as a main component in the presence of a polyfunctional monomer. particles. The acrylic rubber particles may be a single layer of such particles having rubber elasticity, or may be a multi-layered structure having at least one rubber elastic layer. The multi-layered acrylic rubber particles include particles having rubber elasticity as a nucleus and a hard methacrylic acid alkyl ester polymer covering the nucleus, and a hard methacrylic acid alkyl ester polymer. A nucleus surrounded by a rubber-elastic acrylic polymer as described above, or a hard nucleus surrounded by a rubber-elastic acrylic polymer and further surrounded by a hard alkyl methacrylate Examples include those covered with a system polymer. It is preferable that the average diameter of the rubber particles formed in the elastic layer is usually in the range of 50 to 400 nm.

When the (meth)acrylic resin contains rubber particles, the content thereof is usually about 5 to 50 parts by mass per 100 parts by mass of the (meth)acrylic resin. Since the (meth)acrylic resin and the acrylic rubber particles are commercially available in a mixed state, the commercially available product may be used. Examples of commercially available (meth)acrylic resins containing acrylic rubber particles include "HT55X" and "Technoloy S001" sold by Sumitomo Chemical Co., Ltd. "Technolloy S001" is sold in film form.

Cyclic olefin resins are readily available on the market. Commercially available cyclic olefin resins include “Topas” (registered trademark) [Ticona (Germany)], “Arton” (registered trademark) [JSR Corporation], “ZEONOR” (registered trademark) [Japan Zeon Co., Ltd.], "ZEONEX" (registered trademark) [Nippon Zeon Co., Ltd.] and "APEL" (registered trademark) [Mitsui Chemicals, Inc.]. Such a cyclic olefin resin can be used as a substrate by forming a film by a known method such as a solvent casting method or a melt extrusion method. A commercially available cyclic olefin resin base material can also be used. Commercially available cyclic olefin resin substrates include "Escina" (registered trademark) [Sekisui Chemical Co., Ltd.], "SCA40" (registered trademark) [Sekisui Chemical Co., Ltd.], and "Zeonor Film" (registered trademark). ) [Optes Co., Ltd.] and “Arton Film” (registered trademark) [JSR Co., Ltd.].

When the cyclic olefin-based resin is a copolymer of a cyclic olefin and a linear olefin or an aromatic compound having a vinyl group, the content ratio of structural units derived from the cyclic olefin is the total structural units of the copolymer. It is usually 50 mol % or less, preferably in the range of 15 to 50 mol %. Linear olefins include ethylene and propylene, and vinyl-containing aromatic compounds include styrene, α-methylstyrene and alkyl-substituted styrenes. When the cyclic olefin-based resin is a terpolymer of a cyclic olefin, a chain olefin, and an aromatic compound having a vinyl group, the content of structural units derived from the chain olefin is The content of structural units derived from an aromatic compound having a vinyl group is usually 5 to 80 mol% of the total structural units, and the content of the structural units is usually 5 to 80 mol% of the total structural units of the copolymer. is. Such terpolymers have the advantage that relatively small amounts of expensive cyclic olefins can be used in their production.

A long substrate made of the resin as described above is continuously arranged such that the smaller angle between the orientation axis and the longitudinal direction of the substrate is 10° to 30° or 60° to 80°. A retardation layer composed of a long stretched film that satisfies the formula (1) can be produced by stretching in an oblique direction so as to be linearly inclined. As a method of stretching in an oblique direction, for example, a base roll in which a long base material is wound into a roll is prepared, the base material is continuously unwound from the base roll, and the unwound base material is is conveyed and heated, and stretched in an oblique direction inclined at a desired angle with respect to the longitudinal direction of the base material. As such a stretching method, for example, the methods described in JP-A-50-83482 and JP-A-2-113920 can be employed.

The heating temperature of the substrate when stretching the long substrate in the oblique direction is preferably in the range of the temperature (° C.) near the glass transition temperature of the substrate to the glass transition temperature + 100 ° C. The temperature near the glass transition temperature ( ° C.) to the glass transition temperature +50° C. is more preferable. In the present specification, "a temperature (°C) in the vicinity of the glass transition temperature" means about ±5°C of the glass transition temperature of the substrate.

In the long laminate of the present invention, the thickness of the retardation layer formed from the stretched film may be appropriately determined according to the structure of the long laminate, the display device to which it is applied, etc., but it is usually 300 μm or less. It is preferably 5 µm or more, more preferably 10 µm or more, and preferably 100 µm or less, more preferably 50 µm or less. When the thickness of the retardation layer formed of the stretched film is within the above range, it is preferable from the viewpoint of thinning the laminate, and when incorporated as a member constituting the elliptically polarizing plate, the effect of suppressing hue change and flexibility are obtained. easier to improve.

In the present invention, either one of the first retardation layer and the second retardation layer is a retardation layer formed from a cured liquid crystal film. A cured liquid crystal film is usually obtained by applying a polymerizable liquid crystal composition containing a polymerizable liquid crystal compound onto a photo-alignment film and curing the polymerizable liquid crystal composition in a state in which the polymerizable liquid crystal compound is aligned. The polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition forming the retardation layer is usually a liquid crystal compound having a polymerizable group, particularly a photopolymerizable group. The polymerizable liquid crystal compound is not particularly limited as long as it can form a liquid crystal cured film satisfying the above formula (2). For example, conventionally known rod-shaped or disk-shaped polymerizable liquid crystal compounds in the field of retardation films. can be used. As a polymerizable liquid crystal compound forming a retardation layer composed of a cured liquid crystal film, only one type may be used, or two or more types may be used in combination.

When the rod-shaped polymerizable liquid crystal compound is horizontally aligned with respect to the substrate, the optical axis of the polymerizable liquid crystal compound coincides with the long axis direction of the polymerizable liquid crystal compound, and the disk-shaped polymerizable liquid crystal compound is aligned. , the optical axis of the polymerizable liquid crystal compound is present in a direction orthogonal to the disk plane of the polymerizable liquid crystal compound. In order for a layer formed by polymerizing a polymerizable liquid crystal compound to exhibit an in-plane retardation, the polymerizable liquid crystal compound may be oriented in an appropriate direction. When the polymerizable liquid crystal compound is rod-shaped, an in-plane retardation is produced by aligning the optical axis of the polymerizable liquid crystal compound horizontally with respect to the substrate plane. In this case, the optical axis direction and the slow axis direction match. When the polymerizable liquid crystal compound is disk-shaped, an in-plane retardation is developed by aligning the optical axis of the polymerizable liquid crystal compound horizontally with respect to the plane of the substrate. In this case, the optical axis and the slow axis are orthogonal. The alignment state of the polymerizable liquid crystal compound can be adjusted by a combination of the photo-alignment film and the polymerizable liquid crystal compound, and by controlling the alignment state of the polymerizable liquid crystal compound, a retardation layer satisfying formula (2) can be formed. Obtainable.

As the rod-shaped polymerizable liquid crystal compound forming the retardation layer composed of the cured liquid crystal film, for example, a compound containing a group represented by the formula (A) (hereinafter also referred to as "polymerizable liquid crystal compound (A)"). mentioned. The polymerizable liquid crystal compound (A) generally tends to exhibit positive wavelength dispersion as a polymer obtained by polymerizing the polymerizable liquid crystal compound alone in a unidirectionally oriented state. A retardation layer having the optical properties represented by the above formulas (9) and (10) can be obtained by using them.

P11-B11-E11-B12-A11-B13- (A)
[In formula (A), P11 represents a polymerizable group.
A11 represents a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. The hydrogen atom contained in the divalent alicyclic hydrocarbon group and the divalent aromatic hydrocarbon group is a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group or a nitro group. A hydrogen atom contained in the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may be substituted with a fluorine atom.
B11 is -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -CO-NR ¹ -, -NR ¹ -CO-, -CO-, - represents CS- or a single bond. R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
B12 and B13 each independently represent -C≡C-, -CH=CH-, -CH ₂ -CH ₂ -, -O-, -S-, -C(=O)-, -C(=O ) -O-, -O-C(=O)-, -O-C(=O)-O-, -CH=N-, -N=CH-, -N=N-, -C(=O ) -NR ¹ -, -NR ¹ -C(=O)-, -OCH ₂ -, -OCF ₂ -, -CH ₂ O-, -CF ₂ O-, -CH=CH-C(=O)- represents O-, -OC(=O)-CH=CH- or a single bond; R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
E11 represents an alkanediyl group having 1 to 12 carbon atoms, the hydrogen atom contained in the alkanediyl group may be substituted with an alkoxy group having 1 to 5 carbon atoms, and the hydrogen atom contained in the alkoxy group may be substituted with a halogen atom. -CH ₂ - constituting the alkanediyl group may be replaced with -O- or -CO-. ]

The number of carbon atoms in the aromatic hydrocarbon group and alicyclic hydrocarbon group of A11 is preferably in the range of 3 to 18, more preferably in the range of 5 to 12, particularly 5 or 6. preferable. A11 is preferably a cyclohexane-1,4-diyl group or a 1,4-phenylene group.

E11 is preferably a linear alkanediyl group having 1 to 12 carbon atoms. —CH ₂ — constituting the alkanediyl group may be replaced with —O—.
Specifically, methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane -1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group and dodecane-1,12- Linear alkanediyl groups having 1 to 12 carbon atoms such as diyl groups; -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -, -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O- CH ₂ -CH ₂ - and -CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O-CH ₂ -CH ₂ -O-CH ₂ -CH ₂ - and the like.
B11 is preferably -O-, -S-, -CO-O- or -O-CO-, and more preferably -CO-O-.
B12 and B13 each independently represent -O-, -S-, -C(=O)-, -C(=O)-O-, -OC(=O)-, -OC (=O)-O- is preferred, and -O- or -OC(=O)-O- is more preferred.

［式（Ｐ－１１）～（Ｐ－１５）中、
Ｒ^２～Ｒ^６はそれぞれ独立に、炭素数１～６のアルキル基または水素原子を表わす。］ As the polymerizable group represented by P11, a radically polymerizable group or a cationically polymerizable group is preferable in terms of high polymerization reactivity, particularly photopolymerization reactivity, and handling is easy, and the production of the liquid crystal compound itself is also easy. Therefore, the polymerizable group is preferably a group represented by the following formulas (P-11) to (P-15).

[In the formulas (P-11) to (P-15),
R ² to R ⁶ each independently represent an alkyl group having 1 to 6 carbon atoms or a hydrogen atom. ]

Specific examples of the groups represented by formulas (P-11) to (P-15) include groups represented by the following formulas (P-16) to (P-20).

P11 is preferably a group represented by formulas (P-14) to (P-20), more preferably a vinyl group, a p-stilbene group, an epoxy group or an oxetanyl group.
More preferably, the group represented by P11-B11- is an acryloyloxy group or a methacryloyloxy group.

Examples of the polymerizable liquid crystal compound (A) include compounds represented by formula (I), formula (II), formula (III), formula (IV), formula (V) or formula (VI).
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-B16-E12-B17-P12 (I)
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-F11 (II)
P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-E12-B17-P12 (III)
P11-B11-E11-B12-A11-B13-A12-B14-A13-F11 (IV)
P11-B11-E11-B12-A11-B13-A12-B14-E12-B17-P12 (V)
P11-B11-E11-B12-A11-B13-A12-F11 (VI)
[In the formula,
A11, B11 to B13 and P11 are the same as in formula (A) above;
A12 to A14 are each independently synonymous with A11, B14 to B16 are each independently synonymous with B12, B17 is synonymous with B11, E12 is synonymous with E11, and P12 is synonymous with P11.
F11 is a hydrogen atom, an alkyl group having 1 to 13 carbon atoms, an alkoxy group having 1 to 13 carbon atoms, a cyano group, a nitro group, a trifluoromethyl group, a dimethylamino group, a hydroxy group, a methylol group, a formyl group, a sulfo group; (—SO ₃ H), a carboxy group, an alkoxycarbonyl group having 1 to 10 carbon atoms or a halogen atom, and —CH ₂ — constituting the alkyl group and the alkoxy group may be replaced with —O— good. ]

As a specific example of the polymerizable liquid crystal compound (A), "3.8.6 Network (fully crosslinked type)" in Liquid Crystal Handbook (Edited by Liquid Crystal Handbook Editing Committee, published by Maruzen Co., Ltd. on October 30, 2000). , Compounds having a polymerizable group among the compounds described in "6.5.1 Liquid crystal material b. Polymerizable nematic liquid crystal material", JP 2010-31223, JP 2010-270108, JP Examples thereof include polymerizable liquid crystals described in JP-A-2011-6360 and JP-A-2011-207765.

Specific examples of the polymerizable liquid crystal compound (A) include the following formulas (I-1) to (I-4), formulas (II-1) to (II-4), formulas (III-1) to formulas (III-26), formulas (IV-1) to (IV-26), formulas (V-1) to (V-2) and formulas (VI-1) to (VI-6) compound. In the following formula, k1 and k2 each independently represent an integer of 2-12. Such a polymerizable liquid crystal compound is preferable in terms of ease of synthesis or availability.

As the disk-shaped polymerizable liquid crystal compound forming the retardation layer composed of the cured liquid crystal film, for example, a compound containing a group represented by formula (B) (hereinafter also referred to as "polymerizable liquid crystal compound (B)"). is mentioned.

［式（Ｂ）中、Ｒ^１１は、それぞれ独立に、下記式（Ｂ－１）～（Ｂ－５）のいずれかを表す。］

[In the formula (B), each R ¹¹ independently represents any one of the following formulas (B-1) to (B-5). ]

X ¹¹ and Z ¹¹ in formulas (B-1) and (B-5) represent an alkanediyl group having 1 to 12 carbon atoms, and the hydrogen atoms contained in the alkanediyl groups have 1 to 5 carbon atoms. and a hydrogen atom contained in the alkoxy group may be substituted with a halogen atom. -CH ₂ - constituting the alkanediyl group may be replaced with -O- or -CO-. In formulas (B-1) to (B-4), m1 is 1 to 12.

Specific examples of the polymerizable liquid crystal compound (B) include "6.5.1 Liquid crystal material b. Liquid crystal material FIG. 6.21”, JP-A-7-258170, JP-A-7-30637, JP-A-7-309807, JP-A-8-231470 Polymerizable liquid crystal compounds described in etc.

Since any of the rod-shaped or disk-shaped polymerizable liquid crystal compounds described above can be used as a material capable of producing a retardation layer that satisfies the formula (2) by controlling the orientation of the polymerizable liquid crystal compound, the liquid crystal in the present invention Any of them can be used as the polymerizable liquid crystal compound forming the retardation layer composed of a cured film, but from the viewpoint of exhibiting birefringence, a rod-like polymerizable liquid crystal compound is preferable, and the polymerizable liquid crystal compound (A) is more preferable. .

The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition forming the retardation layer composed of the cured liquid crystal film is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass, and more preferably. is 85 to 98 parts by mass, more preferably 90 to 95 parts by mass. If the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the orientation of the resulting cured liquid crystal film.

A polymerizable liquid crystal composition forming a retardation layer composed of a cured liquid crystal film contains, in addition to a polymerizable liquid crystal compound, a solvent, a polymerization initiator, a leveling agent, an antioxidant, a photosensitizer, a reactive additive, and the like. It may further contain additives.

Since the polymerizable liquid crystal composition for forming the retardation layer is usually applied onto the photo-alignment film in a state of being dissolved in a solvent, it preferably contains a solvent. As the solvent, a solvent capable of dissolving the polymerizable liquid crystal compound is preferable, and a solvent inert to the polymerization reaction of the polymerizable liquid crystal compound is preferable. Examples of solvents include water, alcohols such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, 2-butoxyethanol and propylene glycol monomethyl ether. Solvent; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and methyl isobutyl ketone ketone solvents; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; alicyclic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents; chlorine-containing solvents such as chloroform and chlorobenzene; amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone (NMP) and 1,3-dimethyl-2-imidazolidinone; be done. These solvents can be used alone or in combination of two or more. Among these, alcohol solvents, ester solvents, ketone solvents, chlorine-containing solvents, amide solvents and aromatic hydrocarbon solvents are preferred.

The content of the solvent in the polymerizable liquid crystal composition is preferably 50 to 98 parts by mass, more preferably 70 to 95 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal composition. Therefore, the solid content in 100 parts by mass of the polymerizable liquid crystal composition is preferably 2 to 50 parts by mass. When the solid content is 50 parts by mass or less, the viscosity of the polymerizable liquid crystal composition is low, so that the thickness of the film becomes substantially uniform and unevenness tends to be less likely to occur. The solid content can be appropriately determined in consideration of the thickness of the cured liquid crystal film to be produced.

A polymerization initiator is a compound capable of initiating a polymerization reaction of a polymerizable liquid crystal compound or the like by generating reactive species with the contribution of heat or light. Reactive species include active species such as radicals or cations or anions. Among them, a photopolymerization initiator that generates radicals by light irradiation is preferable from the viewpoint that reaction control is easy.

Examples of photopolymerization initiators include benzoin compounds, benzophenone compounds, benzyl ketal compounds, α-hydroxyketone compounds, α-aminoketone compounds, oxime compounds, triazine compounds, iodonium salts and sulfonium salts. Specifically, Irgacure (registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369, Irgacure 379, Irgacure 127, Irgacure 2959, Irgacure 754, Irgacure 379EG (above, BASF Japan Corporation ), Seikuol BZ, Seikuol Z, Seikuol BEE (manufactured by Seiko Chemical Co., Ltd.), Kayacure BP100 (manufactured by Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow), Adeka Optomer SP- 152, Adeka Optomer SP-170, Adeka Optomer N-1717, Adeka Optomer N-1919, Adeka Arkles NCI-831, Adeka Arkles NCI-930 (manufactured by ADEKA Co., Ltd.), TAZ-A, TAZ -PP (manufactured by Nihon SiberHegner Co., Ltd.) and TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.).

Since the photopolymerization initiator can fully utilize the energy emitted from the light source and is excellent in productivity, it is preferable that the maximum absorption wavelength is 300 nm to 400 nm, more preferably 300 nm to 380 nm. Polymerization initiators and oxime photopolymerization initiators are preferred.

α-Acetophenone compounds include 2-methyl-2-morpholino-1-(4-methylsulfanylphenyl)propan-1-one, 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutane-1 -one and 2-dimethylamino-1-(4-morpholinophenyl)-2-(4-methylphenylmethyl)butan-1-one and the like, more preferably 2-methyl-2-morpholino-1-( 4-methylsulfanylphenyl)propan-1-one and 2-dimethylamino-1-(4-morpholinophenyl)-2-benzylbutan-1-one. Commercially available α-acetophenone compounds include Irgacure 369, 379EG, and 907 (manufactured by BASF Japan Ltd.) and Seikuol BEE (manufactured by Seiko Kagaku Co., Ltd.).

Oxime-based photopolymerization initiators generate radicals such as phenyl radicals and methyl radicals when irradiated with light. Polymerization of the polymerizable liquid crystal compound favorably proceeds by these radicals, and among them, an oxime-based photopolymerization initiator that generates methyl radicals is preferable because of its high initiation efficiency of the polymerization reaction. Moreover, from the viewpoint of allowing the polymerization reaction to proceed more efficiently, it is preferable to use a photopolymerization initiator capable of efficiently utilizing ultraviolet rays having a wavelength of 350 nm or more. As a photopolymerization initiator capable of efficiently utilizing ultraviolet light having a wavelength of 350 nm or more, a triazine compound or a carbazole compound containing an oxime structure is preferable, and a carbazole compound containing an oxime ester structure is more preferable from the viewpoint of sensitivity. Examples of oxime photopolymerization initiators include 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methyl benzoyl)-9H-carbazol-3-yl]-1-(O-acetyloxime) and the like. Commercially available oxime ester photopolymerization initiators include Irgacure OXE-01, Irgacure OXE-02, Irgacure OXE-03 (manufactured by BASF Japan Ltd.), Adeka Optomer N-1919, and Adeka Arkles NCI-831. (above, manufactured by ADEKA Corporation) and the like.

The content of the photopolymerization initiator is usually 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, and more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. is. Within the above range, the reaction of the polymerizable group proceeds sufficiently and the orientation of the polymerizable liquid crystal compound is less likely to be disturbed.

By adding an antioxidant, the polymerization reaction of the polymerizable liquid crystal compound can be controlled. The antioxidant may be a primary antioxidant selected from phenolic antioxidants, amine antioxidants, quinone antioxidants, and nitroso antioxidants; It may be a secondary antioxidant selected from system antioxidants. In order to polymerize the polymerizable liquid crystal compound without disturbing the orientation of the polymerizable liquid crystal compound, the content of the antioxidant is usually 0.01 to 10 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. Yes, preferably 0.1 to 5 parts by mass, more preferably 0.1 to 3 parts by mass. An antioxidant can be used individually or in combination of 2 or more types.

Moreover, a photoinitiator can be made highly sensitive by using a photosensitizer. Examples of photosensitizers include xanthones such as xanthone and thioxanthone; anthracenes having substituents such as anthracene and alkyl ether; phenothiazine; and rubrene. A photosensitizer can be used individually or in combination of 2 or more types. The content of the photosensitizer is usually 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. 3 parts by mass.

The polymerizable liquid crystal composition for forming a retardation layer comprising a cured liquid crystal film may contain a reactive additive. The reactive additive preferably has a carbon-carbon unsaturated bond and an active hydrogen reactive group in its molecule. The term "active hydrogen-reactive group" as used herein means a group having reactivity with groups having active hydrogen such as carboxyl group (--COOH), hydroxyl group (--OH), amino group (--NH ₂ ), etc. Representative examples thereof include a glycidyl group, an oxazoline group, a carbodiimide group, an aziridine group, an imide group, an isocyanate group, a thioisocyanate group, a maleic anhydride group, and the like. The number of carbon-carbon unsaturated bonds and active hydrogen reactive groups in the reactive additive is usually 1 to 20 each, preferably 1 to 10 each.

At least two active hydrogen-reactive groups are preferably present in the reactive additive, and in this case, the plurality of active hydrogen-reactive groups may be the same or different.

The carbon-carbon unsaturated bond possessed by the reactive additive may be a carbon-carbon double bond, a carbon-carbon triple bond, or a combination thereof, preferably a carbon-carbon double bond. Among them, the reactive additive preferably contains a carbon-carbon unsaturated bond as a vinyl group and/or a (meth)acrylic group. Furthermore, the active hydrogen-reactive group is preferably at least one selected from the group consisting of an epoxy group, a glycidyl group and an isocyanate group, and a reactive additive having an acrylic group and an isocyanate group is particularly preferred.

Specific examples of reactive additives include compounds having a (meth)acrylic group and an epoxy group, such as methacryloxyglycidyl ether and acryloxyglycidyl ether; compounds having a group; compounds having a (meth)acrylic group and a lactone group, such as lactone acrylate and lactone methacrylate; compounds having a vinyl group and an oxazoline group, such as vinyloxazoline and isopropenyloxazoline; isocyanatomethyl acrylate , isocyanatomethyl methacrylate, 2-isocyanatoethyl acrylate and 20-isocyanatoethyl methacrylate, oligomers of compounds having a (meth)acrylic group and an isocyanate group. Also included are compounds having a vinyl group or vinylene group and an acid anhydride, such as methacrylic anhydride, acrylic anhydride, maleic anhydride and vinyl maleic anhydride. Among them, methacryloxyglycidyl ether, acryloxyglycidyl ether, isocyanatomethyl acrylate, isocyanatomethyl methacrylate, vinyloxazoline, 2-isocyanatoethyl acrylate, 2-isocyanatoethyl methacrylate and the above oligomers are preferred, isocyanatomethyl acrylate, 2-Isocyanatoethyl acrylate and said oligomers are particularly preferred.

［式（Ｙ）中、
ｎは１～１０までの整数を表わし、Ｒ１’は、炭素数２～２０の２価の脂肪族又は脂環式炭化水素基、或いは炭素数５～２０の２価の芳香族炭化水素基を表わす。各繰り返し単位にある２つのＲ２’は、一方が－ＮＨ－であり、他方が＞Ｎ－Ｃ（＝Ｏ）－Ｒ３’で示される基である。Ｒ３’は、水酸基又は炭素－炭素不飽和結合を有する基を表す。
式（Ｙ）中のＲ３’のうち、少なくとも１つのＲ３’は炭素－炭素不飽和結合を有する基である。］ Specifically, compounds represented by the following formula (Y) are preferred.

[In formula (Y),
n represents an integer from 1 to 10, R1' is a divalent aliphatic or alicyclic hydrocarbon group having 2 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 5 to 20 carbon atoms. Represent. One of the two R2' in each repeating unit is -NH- and the other is a group represented by >N-C(=O)-R3'. R3' represents a hydroxyl group or a group having a carbon-carbon unsaturated bond.
At least one R3' among R3' in the formula (Y) is a group having a carbon-carbon unsaturated bond. ]

化合物（ＹＹ）には、市販品をそのまま又は必要に応じて精製して用いることができる。市販品としては、例えば、Ｌａｒｏｍｅｒ（登録商標）ＬＲ－９０００（ＢＡＳＦ社製）が挙げられる。 Among the reactive additives represented by the formula (Y), a compound represented by the following formula (YY) (hereinafter sometimes referred to as compound (YY)) is particularly preferable (n is same meaning as above).

As the compound (YY), a commercially available product can be used as it is or after purification as necessary. Commercially available products include, for example, Laromer (registered trademark) LR-9000 (manufactured by BASF).

When the polymerizable liquid crystal composition contains a reactive additive, the content thereof is usually 0.1 to 30 parts by mass, preferably 0.1 to 5 parts by mass, with respect to 100 parts by mass of the polymerizable liquid crystal compound. Department.

In the long laminate of the present invention, the thickness of the retardation layer formed from the cured liquid crystal film may be appropriately determined according to the configuration of the long laminate, the display device to which it is applied, etc., but it is usually 10 μm or less. . It is preferably 0.5 μm or more, preferably 5 μm or less, more preferably 3 μm or less. When the thickness of the retardation layer formed from the liquid crystal cured film is in the above range, it is preferable from the viewpoint of thinning the laminate, and when incorporated as a member constituting an elliptically polarizing plate, the effect of suppressing hue change and flexibility is easier to improve.

A polymerizable liquid crystal composition for forming a retardation layer composed of a liquid crystal cured film is obtained by stirring a polymerizable liquid crystal compound and, if necessary, other components such as a solvent and a photopolymerization initiator at a predetermined temperature. be able to.

A retardation layer formed from a liquid crystal cured film is, for example,
A step of applying a polymerizable liquid crystal composition for forming a retardation layer onto a photo-alignment film to obtain a coating film;
drying the coating to form a dry coating; and
It can be produced by a method including a step of irradiating a dry coating film with an active energy ray to form a cured liquid crystal film.

In the present invention, the coating film of the polymerizable liquid crystal composition for forming the retardation layer can be usually formed by coating the polymerizable liquid crystal composition for forming the retardation layer on the photo-alignment film described below. . As the coating method of the polymerizable liquid crystal composition, there are usually a spin coating method, an extrusion method, a gravure coating method, a die coating method, a slit coating method, a bar coating method, an applicator method, and a flexographic method. A known method such as a printing method can be employed.

Then, a dry coating film is formed by removing the solvent by drying or the like. Drying methods include natural drying, ventilation drying, heat drying, and reduced pressure drying. By heating the coating film obtained from the polymerizable liquid crystal composition to a liquid crystal phase transition temperature or higher of the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition, the solvent is removed by drying from the coating film, and the polymerizable liquid crystal composition is Since the liquid crystal compound can be aligned in the horizontal direction, heat drying is preferable from the viewpoint of productivity and the like. In general, the liquid crystal phase transition temperature of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition may be lower than the liquid crystal phase transition temperature of the polymerizable liquid crystal compound alone.

The heating temperature of the coating film can be appropriately determined in consideration of the polymerizable liquid crystal compound to be used, the material of the substrate for forming the retardation layer composed of the photo-alignment film or stretched film, etc., but usually the polymerizable liquid crystal compound is used. A temperature equal to or higher than the liquid crystal phase transition temperature is required to cause the phase transition to the liquid crystal phase state. In order to horizontally align the polymerizable liquid crystal compound while removing the solvent contained in the polymerizable liquid crystal composition, the heating temperature is preferably the liquid crystal phase (e.g., nematic phase or smectic phase) transition temperature of the polymerizable liquid crystal compound. The temperature is 3° C. or higher, more preferably 5° C. or higher than the temperature. Although the upper limit of the heating temperature is not particularly limited, it is preferably 180° C. or less, more preferably 150° C. or less in order to avoid damage to the coating film or the retardation layer formed of the stretched film due to heating.
The liquid crystal phase transition temperature can be measured using, for example, a polarizing microscope equipped with a temperature control stage, a differential scanning calorimeter (DSC), a thermogravimetric differential thermal analyzer (TG-DTA), or the like. Further, when two or more kinds of polymerizable liquid crystal compounds are used in combination, the phase transition temperature is obtained by polymerization in which all the polymerizable liquid crystal compounds constituting the polymerizable liquid crystal composition are mixed in the same ratio as the composition in the polymerizable liquid crystal composition. It means a temperature measured using a mixture of polymerizable liquid crystal compounds in the same manner as in the case of using one type of polymerizable liquid crystal compound.

The heating time can be appropriately determined according to the heating temperature, the type of polymerizable liquid crystal compound used, the type of solvent, its boiling point and its amount, etc., but it is usually 15 seconds to 10 minutes, preferably 0.5 to 10 minutes. Five minutes.

The removal of the solvent from the coating film may be carried out simultaneously with the heating of the polymerizable liquid crystal compound to the liquid crystal phase transition temperature or higher, or may be carried out separately. Before heating to the liquid crystal phase transition temperature or higher of the polymerizable liquid crystal compound, the solvent in the coating film is moderately added under conditions in which the polymerizable liquid crystal compound contained in the coating film obtained from the polymerizable liquid crystal composition is not polymerized. A pre-drying step may be provided for removal. Examples of the drying method in the preliminary drying step include a natural drying method, a ventilation drying method, a heat drying method and a reduced pressure drying method, and the drying temperature (heating temperature) in the drying step depends on the type of polymerizable liquid crystal compound used, the can be determined as appropriate according to the type of , its boiling point, its amount, and the like.

Next, in the obtained dried coating film, the polymerizable liquid crystal compound is polymerized while maintaining the horizontal alignment state of the polymerizable liquid crystal compound, thereby forming a cured liquid crystal film in which the polymerizable liquid crystal compound is horizontally aligned. . Examples of the polymerization method include a thermal polymerization method and a photopolymerization method, and the photopolymerization method is preferable from the viewpoint of easy control of the polymerization reaction. In photopolymerization, the light irradiated to the dry coating film includes the type of polymerization initiator contained in the dry coating film, the type of polymerizable liquid crystal compound (especially the type of polymerizable group possessed by the polymerizable liquid crystal compound), and It is appropriately selected according to the amount. Specific examples thereof include at least one kind of light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays and γ-rays, and active electron beams. Among them, ultraviolet light is preferable in that it is easy to control the progress of the polymerization reaction and that a widely used photopolymerization apparatus in the field can be used. It is preferable to select the types of the polymerizable liquid crystal compound and the polymerization initiator contained in the polymerizable liquid crystal composition. The polymerization temperature can also be controlled by light irradiation while cooling the dry coating film with an appropriate cooling means at the time of polymerization. By adopting such cooling means, if the polymerization of the polymerizable liquid crystal compound is carried out at a lower temperature, the material of other layers constituting the long laminate of the present invention, such as the base material forming the first retardation layer, can be obtained. Even if a material having relatively low heat resistance is used for the second retardation layer, the cured liquid crystal film of the second retardation layer can be appropriately formed. It is also possible to accelerate the polymerization reaction by raising the polymerization temperature within a range in which problems (such as deformation due to heat) due to heat during light irradiation do not occur. A patterned cured film can also be obtained by performing masking or development during the photopolymerization.

Examples of the light source of the active energy ray include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, halogen lamps, carbon arc lamps, tungsten lamps, gallium lamps, excimer lasers, and wavelength ranges. LED light sources, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, etc., which emit light in the range of 380 to 440 nm can be used.

The UV irradiation intensity is usually 10 to 3,000 mW/cm ² . The ultraviolet irradiation intensity is preferably in the wavelength range effective for activation of the polymerization initiator. The light irradiation time is usually 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, still more preferably 0.1 seconds to 1 minute. be. When irradiated once or multiple times with such an irradiation intensity of ultraviolet rays, the cumulative amount of light is 10 to 3,000 mJ/cm ² , preferably 50 to 2,000 mJ/cm ² , more preferably 100 to 1,000 mJ/cm. ² .

In the present invention, the coating film of the composition for forming a retardation layer, which is a cured liquid crystal film, is usually formed on the photo-alignment film. The photo-alignment film has an alignment control force that aligns the polymerizable liquid crystal compound in a desired direction. By using a photo-alignment film as the alignment film, it is easy to control the alignment angle of the polymerizable liquid crystal compound with high accuracy, and it is easy to obtain a cured liquid crystal film that is long and has excellent optical properties. In the present invention, the polymerizable liquid crystal compound is oriented in a desired direction, and as a photo-alignment film for obtaining a retardation layer that satisfies the formula (2), the polymerizable liquid crystal compound is usually oriented horizontally with respect to the coating plane. A horizontal alignment photo-alignment film having an alignment control force for alignment is used.

A photo-alignment film is usually formed by applying a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter also referred to as a “composition for forming a photo-alignment film”) to a substrate, and removing the solvent and then polarizing the film. (preferably polarized UV). The photo-alignment film is also advantageous in that the direction of the alignment regulating force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light.

A photoreactive group refers to a group that exhibits liquid crystal alignment ability upon irradiation with light. Specific examples include groups involved in photoreactions that cause liquid crystal alignment ability, such as orientation induction of molecules caused by light irradiation, isomerization reactions, dimerization reactions, photocrosslinking reactions, photodecomposition reactions, and the like. Among them, a dimerization-reactive group or a group involved in a photocrosslinking reaction is preferable, and a dimerization-reactive photoreactive group is more preferable, from the viewpoint of excellent orientation. As the photoreactive group, a group having an unsaturated bond, particularly a double bond is preferable, and a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond Groups having at least one selected from the group consisting of a heavy bond (N=N bond) and a carbon-oxygen double bond (C=O bond) are particularly preferred.

Photoreactive groups having a C═C bond include vinyl groups, polyene groups, stilbene groups, stilbazole groups, stilbazolium groups, chalcone groups and cinnamoyl groups. Photoreactive groups having a C═N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. The photoreactive group having an N=N bond includes an azobenzene group, an azonaphthalene group, an aromatic heterocyclic azo group, a bisazo group, a formazan group, and a group having an azoxybenzene structure. Photoreactive groups having a C=O bond include benzophenone, coumarin, anthraquinone and maleimide groups. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups, and halogenated alkyl groups.

Among them, a dimerization-reactive photoreactive group that participates in the photodimerization reaction is preferable, and a photoalignment film that requires a relatively small amount of polarized light irradiation required for photoalignment and has excellent thermal stability and stability over time can be obtained. A cinnamoyl group and a chalcone group are preferred because they are easy to use. As the polymer having a photoreactive group, a polymer having a cinnamoyl group having a cinnamic acid structure at the end of the polymer side chain is particularly preferred.

The content of the polymer or monomer having a photoreactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of polymer or monomer and the thickness of the desired photo-alignment film. It is preferably at least 0.2% by mass, more preferably in the range of 0.3 to 10% by mass. The composition for forming a photo-alignment film may contain a polymeric material such as polyvinyl alcohol or polyimide, or a photosensitizer, as long as the properties of the photo-alignment film are not significantly impaired.

The coating film of the composition for forming a photo-alignment film may be formed on the substrate, but by forming it directly on the retardation layer formed of the stretched film, the manufacturing process of the long laminate is reduced. It is possible to manufacture a long laminate with high productivity. Examples of the solvent contained in the composition for forming a photo-alignment film include the same solvents as those previously exemplified as the solvent that can be used in the polymerizable liquid crystal composition for forming a retardation layer composed of a cured liquid crystal film. It can be appropriately selected according to the solubility of the polymer or monomer having the group.

The content of the polymer or monomer having a photoreactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of polymer or monomer and the thickness of the desired photo-alignment film. It is preferably at least 0.2% by mass, more preferably in the range of 0.3 to 10% by mass. The composition for forming a photo-alignment film may contain a polymer material such as polyvinyl alcohol or polyimide, or a photosensitizer, as long as the properties of the photo-alignment film are not significantly impaired.

The method of applying the composition for forming a photo-alignment film on the retardation layer formed of a stretched film includes the same method as the method of applying the polymerizable liquid crystal composition for forming the retardation layer on the photo-alignment film. be done. When the long laminate of the present invention is produced by a roll-to-roll type continuous production method, a printing method such as a gravure coating method, a die coating method, or a flexo method is usually employed as the coating method.

Examples of methods for removing the solvent from the coated composition for forming a photo-alignment film include natural drying, ventilation drying, heat drying, and vacuum drying.

In order to irradiate the polarized light, the polarized UV is irradiated directly to the coated photo-alignment film-forming composition after removing the solvent, and the polarized light is irradiated from the retardation layer side formed from the stretched film, A format in which polarized light is transmitted and irradiated may be used. Moreover, it is particularly preferable that the polarized light is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in a wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb the light energy. Specifically, UV (ultraviolet rays) with a wavelength in the range of 250 to 400 nm is particularly preferred. Examples of the light source used for the polarized irradiation include a xenon lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, and an ultraviolet light laser such as KrF or ArF. preferable. Among these, high-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are preferable because of their high emission intensity of ultraviolet rays having a wavelength of 313 nm. Polarized UV can be emitted by passing the light from the light source through a suitable polarizer. As such a polarizer, a polarizing filter, a polarizing prism such as Glan-Thompson or Glan-Taylor, or a wire grid type polarizer can be used.

The number average molecular weight of the photo-alignment film is preferably 20,000 to 100,000, more preferably 25,000 or more, still more preferably 30,000 or more, and more preferably 90,000 or less, still more preferably 80,000 or less. When the number average molecular weight of the photo-alignment film is within the above range, the adhesion with the layer adjacent to the photo-alignment film is enhanced, and the first retardation layer and the second retardation layer are separated through the photo-alignment film. A long laminate laminated with good adhesion can be obtained. The number average molecular weight of the photo-alignment film can be controlled by adjusting the amount of the monomer used in the composition for forming the photo-alignment film, the type and amount of the polymerization initiator, and the like.
The term "number average molecular weight of the photo-alignment film" as used herein substantially corresponds to the number average molecular weight of the polymer constituting the cured photo-alignment film, using a measuring instrument such as gel permeation chromatography. is the molecular weight calculated by measuring the cured photo-alignment film itself. Detailed measurement and calculation methods will be described in Examples below.

The thickness of the photo-alignment film is preferably 100 to 300 nm, more preferably 120 nm or more, still more preferably 130 nm or more, and more preferably 280 nm or less, still more preferably 270 nm or less. When a retardation layer composed of a cured liquid crystal film is formed on a retardation layer composed of a stretched film via a photo-alignment film, the liquid crystal orientation of the polymerizable liquid crystal compound constituting the retardation layer composed of a cured liquid crystal film is different from that of the stretched film. May be affected by orientation. When the thickness of the photo-alignment film is within the above range, the influence of the orientation of the stretched film on the orientation of the polymerizable liquid crystal compound constituting the retardation layer of the cured liquid crystal film is suppressed, and the polymerizable liquid crystal compound is accurately aligned in the desired direction. A retardation layer composed of a well-aligned liquid crystal cured film can be obtained.

The long laminated body of the present invention, which is formed by laminating the first retardation layer, the photo-alignment layer and the second retardation layer in this order, functions as a retardation plate. By further laminating a polarizing layer in addition to such a structure, a long laminate having a function as an elliptically polarizing plate can be obtained.

An example of the layer structure of the long laminate of the present invention that functions as an elliptically polarizing plate will be described with reference to FIG. FIG. 2 is a diagram showing a cross section of the long laminate of the present invention cut in the thickness direction. In the long laminated body 11 of the present invention shown in FIG. A polarizing layer 4 is present on the surface of the retardation layer 1 opposite to the photo-alignment film 3 via an adhesive layer 5, and an adhesive layer is provided on the surface of the polarizing layer 4 opposite to the first retardation layer 1. A protective layer 6 is present via 5 . Another layer such as a protective layer may be present between the first retardation layer 1 and the polarizing layer 4 via the adhesive layer 5, but the first retardation layer 1 and the polarizing layer 4 are From the viewpoint of enhancing adhesion with the polarizing plate 13 included, the first retardation layer 1 and the polarizing layer 4 are preferably adjacent to each other with the adhesive layer 5 interposed therebetween. One of the first retardation layer 1 and the second retardation layer 2 is a stretched film, and the other is a liquid crystal cured film, but from the viewpoint of antireflection function, the first retardation layer 1 is a stretched film. , and the polarizing plate 13 is preferably laminated on the surface of the first retardation layer 1 opposite to the photo-alignment film via an adhesive layer.

A polarizing layer is a layer having a polarizing function. Examples of such a layer include a stretched film to which a dye having anisotropic absorption is adsorbed, or a film containing a film coated with a dye having anisotropic absorption as a polarizer. Dyes having absorption anisotropy include, for example, dichroic dyes.

A film containing, as a polarizer, a stretched film to which a dye having anisotropic absorption is adsorbed is usually produced by uniaxially stretching a polyvinyl alcohol resin film, dyeing the polyvinyl alcohol resin film with a dichroic dye, It is produced through a step of adsorbing the dichroic dye, a step of treating the polyvinyl alcohol-based resin film on which the dichroic dye is adsorbed with an aqueous boric acid solution, and a step of washing with water after the treatment with the aqueous boric acid solution.

A polyvinyl alcohol-based resin is obtained by saponifying a polyvinyl acetate-based resin. Polyvinyl acetate-based resins include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate with other monomers copolymerizable therewith. Other monomers copolymerizable with vinyl acetate include, for example, unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

The degree of saponification of the polyvinyl alcohol resin is usually about 85 to 100 mol %, preferably 98 mol % or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol resin is generally about 1,000 to 10,000, preferably 1,500 to 5,000.

A film obtained by forming such a polyvinyl alcohol-based resin is used as a raw film for the polarizing layer 2 . The method of forming the polyvinyl alcohol-based resin into a film is not particularly limited, and the film can be formed by a known method. The film thickness of the polyvinyl alcohol-based raw film can be, for example, about 10 to 150 μm.

The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before dyeing with a dichroic dye, simultaneously with dyeing, or after dyeing. When uniaxial stretching is performed after dyeing, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. It is also possible to carry out uniaxial stretching in these multiple stages. In the uniaxial stretching, the film may be uniaxially stretched between rolls having different circumferential speeds, or may be uniaxially stretched using hot rolls. The uniaxial stretching may be dry stretching in which the film is stretched in the atmosphere, or may be wet stretching in which the polyvinyl alcohol resin film is stretched in a swollen state using a solvent. The draw ratio is usually about 3 to 8 times.

Dyeing a polyvinyl alcohol resin film with a dichroic dye is performed, for example, by immersing the polyvinyl alcohol resin film in an aqueous solution containing a dichroic dye.

Specifically, iodine and dichroic organic dyes are used as dichroic dyes. Dichroic organic dyes include C.I. I. Dichroic direct dyes composed of disazo compounds such as DIRECT RED 39, and dichroic direct dyes composed of compounds such as trisazo and tetrakisazo are included. In the present invention, iodine is preferably contained as a dichroic dye in the polarizing layer. The polyvinyl alcohol-based resin film is preferably immersed in water before dyeing.

When iodine is used as the dichroic dye, a method of dyeing by immersing a polyvinyl alcohol-based resin film in an aqueous solution containing iodine and potassium iodide is usually employed. The content of iodine in this aqueous solution is usually about 0.01 to 1 part by mass per 100 parts by mass of water. The content of potassium iodide is usually about 0.5 to 20 parts by mass per 100 parts by mass of water. The temperature of the aqueous solution used for dyeing is usually about 20 to 40°C. The immersion time (dyeing time) in this aqueous solution is usually about 20 to 1,800 seconds.

On the other hand, when a dichroic organic dye is used as the dichroic dye, a method of dyeing by immersing a polyvinyl alcohol-based resin film in an aqueous solution containing a water-soluble dichroic dye is usually employed. The content of the dichroic organic dye in this aqueous solution is usually about 1×10 ⁻⁴ to 10 parts by mass, preferably 1×10 ⁻³ to 1 part by mass, more preferably about 1×10 −3 to 1 part by mass, per 100 parts by mass of water. is 1×10 ⁻³ to 1×10 ⁻² parts by mass. This aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing aid. The temperature of the dichroic dye aqueous solution used for dyeing is usually about 20 to 80°C. The immersion time (dyeing time) in this aqueous solution is usually about 10 to 1,800 seconds.

Boric acid treatment after dyeing with a dichroic dye can usually be performed by a method of immersing a dyed polyvinyl alcohol-based resin film in an aqueous boric acid solution. The content of boric acid in the boric acid aqueous solution is usually about 2 to 15 parts by mass, preferably 5 to 12 parts by mass, per 100 parts by mass of water. When iodine is used as the dichroic dye, the boric acid aqueous solution preferably contains potassium iodide, and the content of potassium iodide in that case is usually 0.1 to 0.1 per 100 parts by mass of water. It is about 15 parts by mass, preferably 5 to 12 parts by mass. The immersion time in the boric acid aqueous solution is usually about 60 to 1,200 seconds, preferably 150 to 600 seconds, more preferably 200 to 400 seconds. The temperature of boric acid treatment is usually 50°C or higher, preferably 50 to 85°C, more preferably 60 to 80°C.

The polyvinyl alcohol-based resin film after boric acid treatment is usually washed with water. The water washing treatment can be performed, for example, by immersing the boric acid-treated polyvinyl alcohol-based resin film in water. The temperature of water in the water washing process is usually about 5 to 40°C. The immersion time is usually about 1 to 120 seconds.

After washing with water, a drying treatment is performed to obtain a polarizer. The drying treatment can be performed using, for example, a hot air dryer or a far-infrared heater. The drying temperature is usually about 30 to 100°C, preferably 50 to 80°C. The drying time is usually about 60 to 600 seconds, preferably 120 to 600 seconds. The drying process reduces the moisture content of the polarizer to a practical level. Its moisture content is usually about 5 to 20% by mass, preferably 8 to 15% by mass. When the moisture content is within the above range, a polarizer having moderate flexibility and excellent thermal stability can be obtained.

The thickness of the polarizer obtained by subjecting the polyvinyl alcohol resin film to uniaxial stretching, dyeing with a dichroic dye, boric acid treatment, washing with water and drying is preferably 5 to 40 μm.

Examples of the film coated with a dye having anisotropic absorption include a film obtained by coating a composition containing a dichroic dye having liquid crystallinity or a composition containing a dichroic dye and a polymerizable liquid crystal. mentioned.

It is preferable that the film coated with the dye having anisotropic absorption is thin, but if it is too thin, the strength tends to decrease and the processability tends to be poor. The thickness of the film is usually 20 μm or less, preferably 5 μm or less, more preferably 0.5 to 3 μm.

Specific examples of the film coated with a dye having absorption anisotropy include films described in JP-A-2012-33249.

A transparent protective layer may be laminated on one side or both sides of the polarizing layer thus obtained, for example, via an adhesive layer. The transparent protective layer can contribute to prevention of shrinkage and expansion of the polarizer, prevention of deterioration of the polarizing layer due to temperature, humidity, ultraviolet rays, etc., and prevention of scratches on the polarizing layer.

In the present invention, the transparent protective layer means a protective layer having transparency capable of transmitting visible light, and the term “transparency” refers to a visibility correction transmittance of 80% or more for light rays having a wavelength of 380 nm to 780 nm. It means a characteristic. On the other hand, from the viewpoint of improving the effect of suppressing deterioration of the polarizing layer due to ultraviolet rays, the total light transmittance at 380 nm of the transparent protective layer is preferably 30% or less, more preferably 25% or less, and still more preferably 20% or less. The lower the total light transmittance at 380 nm of the transparent protective layer, the better, but it is usually 0.1% or more.

As the transparent protective layer, a layer having excellent mechanical strength, thermal stability and/or isotropy in addition to transparency is preferable. Specifically, for example, a film composed of a translucent resin can be used, and examples of the substrate for forming the first retardation layer include those exemplified above.

Although the thickness of the transparent protective layer is not particularly limited, it is generally 300 μm or less, preferably 20 to 200 μm, more preferably 30 to 150 μm from the viewpoint of thinning the long laminate. More preferably, it is 40 to 100 μm.

In the long laminate of the present invention, the retardation layer formed from the stretched film can also function as a transparent protective layer. Therefore, by providing a transparent protective layer only on one surface of the polarizing layer and laminating a retardation layer formed of a stretched film on the surface of the protective layer opposite to the transparent protective layer, a thinner layer can be obtained. A long laminate (long elliptically polarizing plate) can be obtained. Therefore, in the present invention, a transparent protective layer, an adhesive layer, a polarizing layer, an adhesive layer, a retardation layer formed from a stretched film, a retardation layer formed from a photo-alignment film and a liquid crystal cured film are laminated in this order. It includes laminates (long elliptically polarizing plates). A long laminate having such a configuration can realize a reduction in thickness compared to a long laminate (elliptically polarizing plate) in which both of the two retardation layers are made of stretched films. In addition, in a long laminate in which both retardation layers are liquid crystal cured films, it is necessary to provide transparent protective layers on both sides of the polarizing layer in order to secure a sufficient protective function for the polarizing layer. On the other hand, in the long laminate of the present invention in which the retardation layer made of a stretched film can also function as a protective layer for the polarizing layer, the transparent protective layer on one side of the polarizing layer is a retardation layer made of a stretched film. This is advantageous in that a thinner laminate can be obtained while ensuring a sufficient protective function for the polarizing layer.

The pressure-sensitive adhesive/adhesive for forming the adhesive layer is not particularly limited, and includes, for example, pressure-sensitive adhesives, water-based adhesives, active energy ray-curable adhesives, and the like. Among them, active energy ray-curable adhesives and water-based adhesives are preferable from the viewpoint of thinning the formed adhesive layer.

The thickness of the adhesive layer may be appropriately determined according to the type of adhesive used, the layer structure of the long laminate, and the like. The thickness of the adhesive layer is usually 0.001 to 5 μm, preferably 0.01 to 2 μm, more preferably 0, from the viewpoint of achieving a thin laminate while ensuring sufficient interlayer adhesion. 0.01 to 0.5 μm.

The long laminate of the present invention, which is obtained by laminating the first retardation layer, the photo-alignment film and the second retardation layer in this order, can be continuously produced by the Roll to Roll method, so productivity can be manufactured well. When the first retardation layer is a stretched film and the second retardation layer is a liquid crystal cured film, for example,
(a) a step of preparing a substrate roll in which a substrate forming a first retardation layer is wound around a winding core;
(b) continuously feeding the substrate from the substrate roll;
(c) a step of stretching the conveyed base material at a desired angle oblique to the longitudinal direction of the base material to form a long first retardation layer;
(d) continuously forming a photo-alignment film on the first retardation layer obtained in (c); and
(e) It can be produced by a method including a step of continuously forming a cured liquid crystal film as a second retardation layer on the photo-alignment film obtained in (d) above.

In the above method, the steps (a) to (c) of forming the first retardation layer, the step (d) of forming the photo-alignment film, and the step (e) of forming the second retardation layer are continuous. After step (c) and / or step (d), a long first retardation layer formed or a long length in which a photo-alignment film is laminated on the first retardation layer The laminate may be wound around a winding core, and the subsequent steps may be performed separately and not continuously. Further, instead of steps (a) to (c), a commercially available long stretched film roll that satisfies the formula (1) may be used, and the first retardation layer, the photo-alignment film and the second position When layers other than the retardation layer are included, a step of forming the other layers may be included.

The method for producing the first retardation layer made of the stretched film by the method including the above steps (a) to (c) is as described above as the method for producing the retardation layer formed from the stretched film. Further, on the retardation layer made of a long stretched film, a second retardation layer made of a liquid crystal cured film is formed so that the slow axis of the obtained retardation layer has a specific angle with respect to the longitudinal direction. By doing so, the long laminate of the present invention that satisfies the formulas (1) and (2) is obtained. The method for forming the retardation layer composed of the liquid crystal cured film is as described above.

Furthermore, the long laminate of the present invention containing a polarizing layer and a transparent protective layer can be obtained by performing the steps (a) to (e) above,
(f) Step of continuously laminating a polarizing layer on the surface of the first retardation layer or the second retardation layer opposite to the photo-alignment film via an adhesive layer (g) Retardation layer of the polarizing layer It can be manufactured by a method including a step of continuously laminating a transparent protective layer on the surface opposite to the surface with an adhesive layer interposed therebetween. Steps (f) and (g) may be performed continuously with steps (a) to (e), or separately from steps (a) to (e), an adhesive layer may be provided on one or both sides of the polarizing layer. First, a long laminate with a transparent protective layer formed through is produced, and the laminate is a first retardation layer, a long laminate composed of a photo-alignment film and a second retardation layer. It may be laminated thereon via an adhesive layer.

In the long laminate of the present invention, when the first retardation layer and the second retardation layer and the polarizing layer are laminated, the slow axis of the first retardation layer and the absorption axis of the polarizing layer The angle formed is 12 to 25° or 65 to 78°, and the angle formed by the slow axis of the second retardation layer and the absorption axis of the polarizing layer is 2θa+42°≦θb≦2θa+48°. preferable. The first retardation layer constituting the long laminate of the present invention satisfies the formula (1), and the slow axis is oblique to the longitudinal direction at a specific angle. By using a retardation layer having such a slow axis, a general polarizing film such as produced by uniaxially stretching a polyvinyl alcohol resin film in the traveling direction (longitudinal direction) can be made into a long film. It can be laminated with the retardation layer by the Roll to Roll method. As a result, a long laminate that functions as an elliptically polarizing plate can be continuously produced using a commercially available general polarizing film roll without requiring special operations or equipment. Allows for efficient manufacturing.

The long laminate of the present invention may have a structure similar to that of a conventional general elliptically polarizing plate, or a polarizing film and a retardation plate. Such a configuration includes, for example, an adhesive layer (sheet) for bonding the long laminate of the present invention functioning as an elliptically polarizing plate to a display element such as an organic EL.

In the present invention, the width, length, and the like of the long laminate are not particularly limited, and can be appropriately determined according to the layer structure, application, manufacturing equipment, and the like of the long laminate. The length of the long laminate is usually 10 to 10,000 m, preferably 50 to 5,000 m.

The long laminate of the present invention has a high effect of suppressing light leakage when incorporated as a member constituting an elliptically polarizing plate, and has a small change in front color hue, so it is suitable as a constituent member of a display device. Available. Therefore, the present invention also includes a display device including a sheet obtained from the long laminate of the present invention.

The long laminate of the present invention can be used for various display devices.
A display device is a device having a display element, and includes a light-emitting element or a light-emitting device as a light source. Examples of display devices include liquid crystal displays, organic electroluminescence (EL) displays, inorganic electroluminescence (EL) displays, touch panel displays, electron emission displays (e.g. field emission displays (FED), surface field emission displays). (SED)), electronic paper (display device using electronic ink or electrophoretic element, plasma display device, projection display device (e.g. grating light valve (GLV) display device, display device having digital micromirror device (DMD) ) and piezoelectric ceramic displays, etc. Liquid crystal display devices include transmissive liquid crystal display devices, transflective liquid crystal display devices, reflective liquid crystal display devices, direct view liquid crystal display devices, projection type liquid crystal display devices, and the like. The display device may be a display device for displaying a two-dimensional image, or a stereoscopic display device for displaying a three-dimensional image.In particular, the long laminate of the present invention is an organic electroluminescence (EL) display devices and inorganic electroluminescence (EL) display devices The long laminate of the present invention can be incorporated into various display devices as sheets of various sizes and shapes. These display devices can exhibit good image display characteristics by being provided with the elliptically polarizing plate of the present invention having excellent optical characteristics.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Unless otherwise specified, "%" and "parts" in the examples mean % by mass and parts by mass, respectively.

溶剤（９５部）：シクロペンタノン 1. Example 1
(1) Preparation of composition for forming a photo-alignment film A composition for forming a photo-alignment film was obtained by mixing the following components and stirring the resulting mixture at 80°C for 1 hour.
Photo-orientable material (5 parts):

Solvent (95 parts): Cyclopentanone

(2) Preparation of polymerizable liquid crystal composition The composition of the polymerizable liquid crystal composition is shown below. After mixing each component and stirring the resulting solution at 80° C. for 1 hour, the mixture was cooled to room temperature to obtain a polymerizable liquid crystal composition.
<Composition>
Polymerizable liquid crystal: LC242 (manufactured by BASF) 19.2 parts Polymerization initiator: Irg907 (manufactured by BASF Japan) 0.5 parts Leveling agent: BYK-361N (manufactured by BYK Chemie Japan) 0.1 parts Reactive additive: LR -9000 1.1 parts (Laromer (registered trademark) manufactured by BASF Japan)
Solvent: PGMEA 79.1 parts
(Propylene glycol 1-monomethyl ether 2-acetate)

(3) Production of first retardation layer made of stretched film With reference to the first retardation phase of JP-A-2013-235272, a long cycloolefin polymer (COP) film manufactured by Nippon Zeon Co., Ltd. (Product name: ZEONOR) was obliquely stretched with respect to the direction (width direction) perpendicular to the traveling direction to form a first retardation layer. When performing the oblique stretching, one peripheral edge of the COP film was pulled in the width direction as it was, and the other peripheral edge was pulled in an oblique direction with respect to the width direction. When the retardation value of the obtained retardation film was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd., Re (550) = 271 nm, the retardation of the longitudinal direction and the first retardation layer The smaller angle among the angles formed by the axes was 15°. Moreover, when the film thickness of the first retardation layer was measured with an ellipsometer, it was 1.9 μm.

(4) Production of long laminate (retardation plate) (i) Preparation of photo-alignment film The first retardation layer is treated with a corona treatment device (AGF-B10, manufactured by Kasuga Denki Co., Ltd.) with an output of 0. The treatment was performed once under the conditions of 3 kW and a treatment speed of 3 m/min. A composition for forming a photo-alignment film was applied to the corona-treated surface using a bar coater, dried at 80° C. for 1 minute, and irradiated with a polarized UV irradiation device (SPOT CURE SP-7; manufactured by Ushio Inc.). , polarized UV exposure was performed at an angle of 75° with respect to the longitudinal direction of the COP with an integrated light dose of 100 mJ/cm ² . The film thickness of the resulting photo-alignment film was measured with an ellipsometer and found to be 150 nm.
(ii) Number Average Molecular Weight of Photo-Alignment Film The number average molecular weight of the obtained photo-alignment film was measured according to the following method.
Apparatus; HLC-8220GPC (manufactured by Tosoh Corporation)
Column; TOSOH TSKgel Multipore HXL-M
Column temperature; 40°C
Solvent; THF (tetrahydrofuran)
Flow rate; 1.0 mL/min Detector; RI
Calibration standard material; TSK STANDARD POLYSTYRENE F-40, F-4, F-288, A-5000, A-500
(iii) Formation of second retardation layer composed of liquid crystal cured film On the obtained photo-alignment film, the polymerizable liquid crystal composition prepared in (2) above is applied with a bar coater and dried at 100 ° C. for 1 minute. After that, using a high-pressure mercury lamp, a second retardation layer is formed by irradiating ultraviolet rays (in a nitrogen atmosphere, integrated light amount at a wavelength of 365 nm: 1200 mJ/cm ² ), and a long laminate (1) is obtained. Obtained. The film thickness of the obtained second retardation layer was measured with a laser microscope and found to be 970 nm.
The retardation value of the obtained second retardation layer was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd., Re (550) = 135 nm, and the longitudinal direction of the first retardation layer and the slow axis of the second retardation layer, the smaller angle was 75°.

(5) Preparation of long laminate (elliptically polarizing plate) (i) Preparation of water-based adhesive To 100 parts of water, 3 parts of carboxyl group-modified polyvinyl alcohol (Kuraray Poval KL318; manufactured by Kuraray Co., Ltd.) and water-soluble polyamide epoxy A water-based adhesive was prepared by adding 1.5 parts of a resin (Sumireze Resin 650; an aqueous solution having a solid concentration of 30%, manufactured by Sumika Chemtex Co., Ltd.).

(ii) Production of polarizing layer A 30 µm-thick polyvinyl alcohol film (average degree of polymerization: about 2400, degree of saponification: 99.9 mol% or more) was uniaxially stretched by about 5 times by dry stretching and kept in a tensioned state. It was immersed in pure water at 40° C. for 40 seconds. After that, it was dyed by immersing it in a dyeing aqueous solution having a mass ratio of iodine/potassium iodide/water of 0.044/5.7/100 at 28° C. for 30 seconds. Next, it was immersed in an aqueous boric acid solution having a mass ratio of potassium iodide/boric acid/water of 11.0/6.2/100 at 70° C. for 120 seconds. Subsequently, after washing with pure water at 8°C for 15 seconds, the film was dried at 60°C for 50 seconds and then at 75°C for 20 seconds while maintaining a tension of 300N. A polarizing layer (polarizer) having a thickness of 12 μm was obtained.

A triacetyl cellulose film (TAC; KC2UA; manufactured by Konica Minolta, Inc., total light transmittance at 380 nm: 18%, thickness: 25 μm) was saponified on one side of the obtained polarizing layer as a front transparent protective layer. The treated film is laminated on the other surface of the long laminate (1) so that the surface of the polarizing layer opposite to the TAC film is on the first retardation layer side, and the thickness of the adhesive layer obtained between A water-based adhesive prepared to have a thickness of 50 nm was injected, and the layers were bonded together with a nip roll. The resulting laminate was dried at 60° C. for 2 minutes while maintaining a tension of 430 N/m, and an elliptically polarized light having a triacetyl cellulose film as a transparent protective film on one side and a long laminate (1) on one side. got a board The layer structure of the elliptically polarizing plate is a front transparent protective layer/adhesive layer/polarizing layer/adhesive layer/first retardation layer composed of stretched film/photo-alignment film/second retardation layer composed of cured liquid crystal film. there were.

(6) Confirmation of adhesion A sample for adhesion test (10 cm long × 10 cm wide) is cut out from the prepared long elliptically polarizing plate, and a 5 cm cellotape (registered trademark) is attached to one end of the sample. After adhering so that the adhesive part was 2 cm, the sellotape was peeled off in the direction of 90° to the adhesive surface, and the adhesiveness was evaluated according to the following evaluation criteria. Table 1 shows the results.
<Evaluation Criteria>
(I) Adhesion between the photo-alignment film and the first retardation layer ○: No peeling occurred between the photo-alignment film and the first retardation layer and / or the second retardation layer △: Photo-alignment Partial peeling occurred between the film and the first retardation layer and / or the second retardation layer ×: the photo-alignment film and the first retardation layer and / or the second retardation layer Almost or completely peeled off The peeling of the alignment film layer is shown in the column of "photo-alignment film layer" in Table 1.
(ii) Adhesion between the polarizing layer and the retardation layer ○: No peeling occurred between the polarizing layer and the retardation layer △: Partial peeling occurred between the polarizing layer and the retardation layer ×: Polarized light Peeling between the polarizing plate and the retardation layer is almost or completely separated from the retardation layer.

(7) Measurement of SCI reflectance The surface of the elliptically polarizing plate on the side of the second retardation layer was attached to a mirror using an adhesive. The SCI reflectance and reflection hues a* and b* of the elliptically polarizing plate attached to the mirror were measured using CM2600d manufactured by Konica Minolta. Table 1 shows the results.

2. Example 2
A long laminate was produced in the same manner as in Example 1, except that the first retardation layer and the second retardation layer were changed as shown in Table 1, and various physical properties were evaluated. Table 1 shows the results.

3. Example 3
A long laminate was produced in the same manner as in Example 1, except that the first retardation layer and the second retardation layer were changed as shown in Table 1, and various physical properties were evaluated. Table 1 shows the results.

4. Example 4
A long laminate was produced in the same manner as in Example 1, except that the first retardation layer and the second retardation layer were changed as shown in Table 1, and various physical properties were evaluated. Table 1 shows the results.

5. Example 5
Instead of triacetyl cellulose as the front protective layer, a norbornene resin film containing an ultraviolet absorber (product name Zeonor, manufactured by Nippon Zeon Co., Ltd., total light transmittance at 380 nm: 8%) was used. A long laminate was produced in the same manner as in Example 1, except that the second retardation layer was changed as shown in Table 1, and various physical properties were evaluated. Table 1 shows the results.

6. Example 6
A long laminate was produced in the same manner as in Example 1, except that the photo-alignment film having the number average molecular weight shown in Table 1 was used, and various physical properties were evaluated. Table 1 shows the results.

7. Example 7
A long laminate was produced in the same manner as in Example 1, except that the photo-alignment film having the number average molecular weight shown in Table 1 was used, and various physical properties were evaluated. Table 1 shows the results.

8. Example 8
A saponified triacetyl cellulose film (TAC; KC2UA; manufactured by Konica Minolta, Inc.) is applied to one surface of the polarizing layer, and a triacetyl cellulose film (TAC; KC2UA; manufactured by Konica Minolta, Inc.) is applied to the other surface. were laminated with a water-based adhesive to obtain a polarizing plate. In the same manner as in Example 1, except that the non-saponified triacetyl cellulose surface of the obtained polarizing plate and the first retardation layer of the long laminate (1) were laminated with a water-based adhesive, a long A scale laminate was produced and various physical properties were evaluated. Table 1 shows the results.

9. Example 9
In the same manner as in Example 1, except that the long laminate (1) was laminated so that the surface opposite to the TAC film of the polarizing layer was on the (second) retardation layer side made of the cured liquid crystal film, the front surface A long laminate (elliptically polarizing plate) composed of a transparent protective layer / adhesive layer / polarizing layer / adhesive layer / retardation layer composed of a cured liquid crystal film / photo-alignment film / retardation layer composed of a stretched film is produced, Various physical properties were evaluated. Table 1 shows the results.

10. Comparative example 1
Table 1 shows the smaller of the angles formed by the longitudinal direction and the slow axis of the first retardation layer and the angle formed by the longitudinal direction of the first retardation layer and the slow axis of the second retardation layer. A long laminate was produced in the same manner as in Example 1 except that the angle described in 1. was used, and various physical properties were evaluated. Table 1 shows the results.

11. Comparative example 2
Table 1 shows the smaller of the angles formed by the longitudinal direction and the slow axis of the first retardation layer and the angle formed by the longitudinal direction of the first retardation layer and the slow axis of the second retardation layer. A long laminate was produced in the same manner as in Example 1 except that the angle described in 1. was used, and various physical properties were evaluated. Table 1 shows the results.

12. Comparative example 3
Table 1 shows the smaller of the angles formed by the longitudinal direction and the slow axis of the first retardation layer and the angle formed by the longitudinal direction of the first retardation layer and the slow axis of the second retardation layer. A long laminate was produced in the same manner as in Example 1 except that the angle described in 1. was used, and various physical properties were evaluated. Table 1 shows the results.

1: first retardation layer 2: second retardation layer 3: photo-alignment film 4: polarizing layer 5: adhesive layer 6: protective layer 11: long laminate 12: retardation plate 13: polarizing plate

Claims (8)

A long laminate having a first retardation layer, a photo-alignment film, and a second retardation layer in this order,
The photo-alignment film has a number average molecular weight of 20,000 to 100,000,
A long laminate satisfying the following formulas (1) and (2), wherein one of the first retardation layer and the second retardation layer is a stretched film and the other is a liquid crystal cured film.
10°≦θa≦30° or 60°≦θa≦80° (1)
2θa+40°≦θb≦2θa+50° (2)
[In the formula, θa is the smaller of the angles formed by the longitudinal direction of the long laminate and the slow axis of the first retardation layer, and θb is the longitudinal direction of the first retardation layer and the It is the angle formed with the slow axis of the second retardation layer. ] 2. The long laminate according to claim 1, wherein the first retardation layer satisfies the following formula (3), and the second retardation layer satisfies the following formula (4).
200nm<Re(550)<320nm (3)
100nm<Re(550)<160nm (4)
[In the formula, Re(550) represents an in-plane retardation value at a wavelength of 550 nm. ] 3. The long laminate according to claim 1, wherein the photoreactive group of the photo-alignment film is a dimerization-reactive photoreactive group. The long laminate according to any one of claims 1 to 3 , wherein the photo-alignment film has a thickness of 100 to 300 nm. Having a transparent protective layer, an adhesive layer, a polarizing layer, an adhesive layer, a first retardation layer, a photo-alignment film and a second retardation layer in this order,
The long laminate according to any one of claims 1 to 4 , wherein the first retardation layer is a stretched film and the second retardation layer is a liquid crystal cured film. 6. The long laminate according to claim 5 , wherein the transparent protective layer has a total light transmittance at 380 nm of 30% or less. 7. The long laminate according to claim 5 , wherein the polarizing layer contains iodine as a dichroic dye, and the absorption axis of the polarizing layer is in the longitudinal direction of the long laminate. An organic EL display device comprising a sheet obtained from the long laminate according to any one of claims 1 to 7 .

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