阅读说明：本技术 层叠体、有机电致发光装置、液晶显示装置 (Laminate, organic electroluminescent device, and liquid crystal display device ) 是由 柴田直也 芥川畅之 吉政庆介 佐多博晓 于 2019-02-26 设计创作，主要内容包括：本发明提供一种具有起偏器及光学各向异性层且耐热性优异的层叠体、具有层叠体的有机电致发光装置及液晶显示装置。本发明的层叠体具有2个基板和配置于2个基板之间的偏振片,该层叠体中,偏振片具有起偏器及光学各向异性层,起偏器包含聚乙烯醇系树脂,光学各向异性层为使用包含由通式(I)表示的聚合性液晶化合物的组合物形成的层,基板的透湿度为10<Sup>-3</Sup>g/m<Sup>2</Sup>·day以下,偏振片的含水量为3.0g/m<Sup>2</Sup>以下,L<Sub>1</Sub>-G<Sub>1</Sub>-D<Sub>1</Sub>-Ar-D<Sub>2</Sub>-G<Sub>2</Sub>-L<Sub>2</Sub>……(I)。(The invention provides a laminate having a polarizer and an optically anisotropic layer and having excellent heat resistance, an organic electroluminescent device having the laminate, and a liquid crystal display device. The laminate of the present invention comprises 2 substrates and a polarizing plate disposed between the 2 substrates, wherein the polarizing plate comprises a polarizer and an optically anisotropic layer, the polarizer comprises a polyvinyl alcohol resin, the optically anisotropic layer is a layer formed using a composition comprising a polymerizable liquid crystal compound represented by general formula (I), and the substrates have a moisture permeability of 10 ‑3 g/m 2 Day or less, water content of polarizing plate 3.0g/m 2 Below, L 1 ‑G 1 ‑D 1 ‑Ar‑D 2 ‑G 2 ‑L 2 ……(I)。)

1. A laminate having 2 substrates and a polarizing plate disposed between the 2 substrates, wherein in the laminate,

the polarizing plate has a polarizer and an optically anisotropic layer,

the polarizer comprises a polyvinyl alcohol resin,

the optically anisotropic layer is a layer formed using a composition containing a polymerizable liquid crystal compound represented by the general formula (I),

the substrate has a moisture permeability of 10^-3g/m²The number of times of day is less than or equal to day,

the water content of the polarizing plate was 3.0g/m²In the following, the following description is given,

L₁-G₁-D₁-Ar-D₂-G₂-L₂(I)

in the general formula (I), D₁And D₂Each independently represents a single bond, -O-, -CO-O-, -C (═ S) O-, -CR¹R²-、-CR¹R²-CR³R⁴-、-O-CR¹R²-、-CR¹R²-O-CR³R⁴-、-CO-O-CR¹R²-、-O-CO-CR¹R²-、-CR¹R²-CR³R⁴-O-CO-、-CR¹R²-O-CO-CR³R⁴-、-CR¹R²-CO-O-CR³R⁴-、-NR¹-CR²R³-or-CO-NR¹-，

R¹、R²、R³And R⁴Each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms,

G₁and G₂Each independently represents a 2-valent alicyclic hydrocarbon group or aromatic hydrocarbon group having 5 to 8 carbon atoms, and a methylene group contained in the alicyclic hydrocarbon group may be substituted by-O-, -S-, or-NH-,

L₁and L₂Each independently represents an organic group having a valence of 1, selected from the group consisting of L₁And L₂At least 1 of the groups represents a 1-valent group having a polymerizable group,

ar represents a 2-valent aromatic ring group represented by the following general formula (II-1), general formula (II-2), general formula (II-3) or general formula (II-4),

general formula (VII)

In the general formulae (II-1) to (II-4), Q₁represents-S-, -O-or-NR¹¹-，R¹¹Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Y₁Z represents an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms₁、Z₂And Z₃Independently represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 1-valent carbon atom and 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group or-NR¹²R¹³or-SR¹²，Z₁And Z₂May be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring, R¹²And R¹³Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, A₁And A₂Each independently is selected from the group consisting of-O-, -NR²¹A group of the group consisting of-S-and-CO-, and R²¹X represents a hydrogen atom or a substituent, X represents a hydrogen atom or a non-metal atom of groups 14 to 16 to which a substituent may be bonded, Ax represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, Ay represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms and which may have a substituent, or an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, Ax and Ay may each have a substituent, Ax and Ay may be bonded to form a ring, and Q₂Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.

2. The laminate according to claim 1, wherein,

the water content of the polarizing plate was 2.3g/m²The following.

3. The laminate according to claim 1 or 2,

the thickness of the polarizer is less than 10 μm.

4. The laminate according to any one of claims 1 to 3,

re (450) as an in-plane retardation at a wavelength of 450nm of the optically anisotropic layer, Re (550) as an in-plane retardation at a wavelength of 550nm of the optically anisotropic layer, and Re (650) as an in-plane retardation at a wavelength of 650nm of the optically anisotropic layer satisfy the relationship Re (450). ltoreq.Re (550). ltoreq.Re (650).

5. The laminate according to any one of claims 1 to 4,

the optically anisotropic layer is a positive a plate.

6. The laminate according to any one of claims 1 to 5,

the optically anisotropic layer is a lambda/4 plate.

7. The laminate according to any one of claims 1 to 6,

a polarizer protective film on at least one surface of the polarizer,

at least 1 of the polarizer protective films contains a norbornene-based resin.

8. An organic electroluminescent device having the laminate according to any one of claims 1 to 7.

9. A liquid crystal display device having the laminate according to any one of claims 1 to 7.

Technical Field

The present invention relates to a laminate, an organic electroluminescent device, and a liquid crystal display device.

Background

Conventionally, a polarizing plate having an optically anisotropic layer and a polarizer has been used for an organic electroluminescent device, a liquid crystal display device, and the like for optical compensation, reflection prevention, and the like.

In recent years, polarizing plates (so-called broadband polarizing plates) have been developed which can provide the same effect to white light, which is a composite wave in which light rays in the visible light region are mixed, in accordance with light rays of all wavelengths, and in particular, optical anisotropic layers included in polarizing plates are also required to be thin in accordance with the demand for thin devices to which polarizing plates are applied.

In response to the above-mentioned demand, patent documents 1 and 2 propose the use of a polymerizable liquid crystal compound having reverse wavelength dispersion properties as a polymerizable compound for forming an optically anisotropic layer.

Prior art documents

Patent document

Patent document 1: international publication No. 2014/010325

Patent document 2: japanese patent laid-open publication No. 2011-207765

Disclosure of Invention

Technical problem to be solved by the invention

However, it was found that: when a polarizing plate having an optically anisotropic layer formed using a polymerizable liquid crystal (polymerizable liquid crystal compound) having reverse wavelength dispersibility described in patent documents 1 and 2 is produced, and the polarizing plate is sandwiched from both sides by substrates having low moisture permeability (for example, glass substrates) according to a practical use method (for example, a circular polarizing plate for preventing reflection in an organic electroluminescence type smartphone), and the obtained laminate is exposed for a long time under a high temperature condition, red tone unevenness occurs in the central portion in the plane of the laminate. The results of the analysis clearly show that: in the red tone region, the in-plane retardation (Re) greatly fluctuates, and the tone changes. Therefore, it is desired to develop a laminate having a polarizer and an optically anisotropic layer, in which a change in-plane retardation is suppressed even when exposed to high temperatures for a long time. Hereinafter, the case where the change in-plane retardation is suppressed when the laminate is exposed to high temperature is expressed as excellent heat resistance.

Accordingly, an object of the present invention is to provide a laminate having a polarizer and an optically anisotropic layer and having excellent heat resistance.

Another object of the present invention is to provide an organic electroluminescent device and a liquid crystal display device each having the laminate.

Means for solving the technical problem

As a result of intensive studies on the above problems, the present inventors have found that the above problems can be solved by the following configuration.

(1) A laminate having 2 substrates and a polarizing plate disposed between the 2 substrates, wherein in the laminate,

the polarizing plate has a polarizer and an optically anisotropic layer,

the polarizer comprises a polyvinyl alcohol resin,

the optically anisotropic layer is a layer formed using a composition containing a polymerizable liquid crystal compound represented by the general formula (I) described later,

the substrate has a moisture permeability of 10^-3g/m²The number of times of day is less than or equal to day,

the water content of the polarizing plate was 3.0g/m²The following.

(2) The laminate according to (1), wherein the polarizing plate has a water content of 2.3g/m²The following.

(3) The laminate according to (1) or (2), wherein the polarizer has a thickness of less than 10 μm.

(4) The laminate according to any one of (1) to (3), wherein Re (450) as an in-plane retardation at a wavelength of 450nm of the optically anisotropic layer, Re (550) as an in-plane retardation at a wavelength of 550nm of the optically anisotropic layer, and Re (650) as an in-plane retardation at a wavelength of 650nm of the optically anisotropic layer satisfy the relationship Re (450). ltoreq.Re (550). ltoreq.Re (650).

(5) The laminate according to any one of (1) to (4), wherein the optically anisotropic layer is a positive A plate.

(6) The laminate according to any one of (1) to (5), wherein the optically anisotropic layer is a λ/4 plate.

(7) The laminate according to any one of (1) to (6), wherein a polarizer protective film is provided on at least one surface of a polarizer,

at least 1 of the polarizer protective films contains a norbornene-based resin.

(8) An organic electroluminescent device having the laminate of any one of (1) to (7).

(9) A liquid crystal display device having the laminate of any one of (1) to (7).

Effects of the invention

According to the present invention, a laminate having a polarizer and an optically anisotropic layer and having excellent heat resistance can be provided.

Further, the present invention can provide an organic electroluminescent device and a liquid crystal display device each having the laminate.

Drawings

Fig. 1 is a schematic cross-sectional view showing an example of an embodiment of a laminate according to the present invention.

Fig. 2 is a schematic cross-sectional view showing another example of the embodiment of the laminate of the present invention.

Detailed Description

The polarizing plate, the organic electroluminescent device, and the liquid crystal display device of the present invention will be described below.

In the present specification, the numerical range expressed by the term "to" means a range in which the numerical values described before and after the term "to" are included as the lower limit value and the upper limit value.

The "orthogonal" and "parallel" angles are strict ranges of ± 10 °, and the "same" and "different" angles can be determined based on whether or not the difference is less than 5 °.

In the present specification, "visible light" means 380 to 780nm visible light. In the present specification, the measurement wavelength is 550nm when the measurement wavelength is not particularly described.

Next, terms used in the present specification will be described.

< slow axis >

In the present specification, the "slow axis" refers to a direction in which the in-plane refractive index is the largest. In addition, the term "slow axis" of the optically anisotropic layer refers to the slow axis of the entire optically anisotropic layer.

＜Re(λ)、Rth(λ)＞

The in-plane retardation (Re (λ)) and the retardation in the thickness direction (Rth (λ)) are values measured using light of a measurement wavelength using axoscan opmf-1 (manufactured by OptoScience, inc.).

Specifically, the average refractive index ((nx + ny + nz)/3) and the film thickness (d (μm)) were input by using Axoscan OPMF-1 as follows:

slow axis direction (°)

Re(λ)＝R0(λ)

Rth(λ)＝((nx+ny)/2-nz)×d。

R0 (. lamda.) is a numerical value calculated by Axoscan OPMF-1, but refers to Re (. lamda.).

In the present specification, the a plate is defined as follows.

The a plate has 2 types, namely a positive a plate (positive a plate) and a Negative a plate (Negative a plate), and when a refractive index in a slow axis direction (direction in which the in-plane refractive index is largest) in a film plane is nx, a refractive index in a direction orthogonal to the in-plane slow axis is ny, and a refractive index in a thickness direction is nz, the positive a plate satisfies a relationship of formula (a1), and the Negative a plate satisfies a relationship of formula (a 2). In addition, Rth of the positive a plate shows a positive value, and Rth of the negative a plate shows a negative value.

Formula (A1) nx > ny ≈ nz

Formula (A2) ny < nx ≈ nz

The term "substantially" as used herein includes not only the case where both are completely identical but also the case where both are substantially identical. The term "substantially the same" is included in "ny ≈ nz" even when (ny-nz) × d (where d is the thickness of the thin film) is-10 to 10nm, preferably-5 to 5nm, and is included in "nx ≈ n z" even when (nx-nz) × d is-10 to 10nm, preferably-5 to 5 nm.

The C plate has 2 types of Positive C plate (Positive C plate) and Negative C plate (Negative C plate), the Positive C plate satisfying the relationship of the formula (C1), and the Negative C plate satisfying the relationship of the formula (C2). In addition, Rth of the positive C plate shows a negative value, and Rth of the negative C plate shows a positive value.

Formula (C1) nz > nx ≈ ny

Formula (C2) nz < nx ≈ ny

The term "substantially" as used herein includes not only the case where both are completely identical but also the case where both are substantially identical. The term "substantially the same" is included in "nx ≈ ny" even when (nx-ny) × d (where d is the thickness of the thin film) is 0 to 10nm, preferably 0 to 5nm, for example.

The present invention is characterized in that the water content of the laminate is adjusted to fall within a predetermined range.

The present inventors have studied the cause of the above-described red color unevenness and found that: when the laminate is exposed to high temperature conditions, decomposition of the structure derived from the liquid crystal compound in the optically anisotropic layer rapidly occurs over a certain derivation period, and the variation in the value of in-plane retardation becomes large.

The reason why the decomposition occurs as described above is found to be influenced by moisture. Namely, it is considered that: when a laminate sandwiched by 2 substrates having low moisture permeability is subjected to heat treatment, moisture contained in a polarizer containing a polyvinyl alcohol resin is less likely to be discharged to the outside of the substrate due to the low moisture permeability of the substrates, and is in a state of being diffused into the optically anisotropic layer, and the decomposition is induced by the moisture. In particular, the polymerizable liquid crystal compound represented by the general formula (I) may have an electron-withdrawing property from the viewpoint of the property of reverse wavelength dispersibility, and as a result, it is estimated that: any carbon atom constituting the polymerizable liquid crystal compound becomes more positively polarized and is easily attacked by a nucleophilic species.

In addition, it is considered that: since no substrate is present on the end face of the optically anisotropic layer, moisture can diffuse out of the laminate, but since the optically anisotropic layer is sandwiched between 2 substrates in the center, decomposition easily occurs, and a larger variation in the value of in-plane retardation occurs.

In contrast, in the present invention, the water content of the laminate itself including the optically anisotropic layer and the polarizer is adjusted to be within a predetermined range, whereby decomposition of the liquid crystal compound and the like are suppressed even when the laminate is exposed under high temperature conditions.

Fig. 1 shows a schematic cross-sectional view of an embodiment of the laminate of the present invention. The laminate 10A includes a1 st substrate 12A, a polarizing plate 14, and a2 nd substrate 12B in this order. That is, the polarizing plate 14 is disposed between the 1 st substrate 12A and the 2 nd substrate 12B. The polarizing plate 14 has a polarizer 16 and an optically anisotropic layer 18.

The respective members will be described in detail below.

< substrate (1 st substrate 12A and 2 nd substrate 12B) >

The laminate had 2 substrates. In fig. 1,2 substrates correspond to the 1 st substrate 12A and the 2 nd substrate 12B.

The substrate has a moisture permeability of 10^-3g/m²Day or less. Among them, from the viewpoint of durability of an organic electroluminescent device and a liquid crystal display device using a laminate, 10 is preferable^-4g/m²Day or less, more preferably 10^-5g/m²Day or less. The lower limit is not particularly limited, but is usually 10^-10g/m²Day or more.

The moisture permeability of the substrate was measured as follows. The measurement was carried out using a water vapor transmission rate measuring apparatus (AQUATRAN 2 (registered trademark) manufactured by MOCON, inc.) under the conditions of a measurement temperature of 40 ℃ and a relative humidity of 90%.

The material constituting the substrate is not particularly limited, and may be inorganic or organic.

The substrate is not particularly limited as long as the moisture permeability is lower than a predetermined value, but a glass substrate and a gas barrier film may be mentioned. More specifically, there are glass substrates such as sealing glass used in organic electroluminescent devices, glass for liquid crystal cells, and surface-coated glass, and gas barrier films such as high barrier films and barrier films used in organic electroluminescent devices.

The substrate may have a single-layer structure or a multi-layer structure.

The substrate is preferably transparent, preferably a so-called transparent substrate.

In the present specification, "transparent" means that the visible light transmittance is 60% or more, preferably 80% or more, and more preferably 90% or more. The upper limit is not particularly limited, but is usually less than 100%.

The thickness of the substrate is not particularly limited, but is preferably 800 μm or less, and more preferably 100 μm or less, from the viewpoint of thinning. The lower limit is not particularly limited, but is preferably 10 μm or more.

< polarizer >

The laminate has a polarizer. The polarizer is a so-called linear polarizer having a function of converting light into specific linearly polarized light.

The polarizer comprises a polyvinyl alcohol resin.

The polyvinyl alcohol resin is a resin containing-CH₂Examples of the resin having a repeating unit of-CHOH-include polyvinyl alcohol and ethylene-vinyl alcohol copolymer.

The polyvinyl alcohol resin is obtained by, for example, saponifying a polyvinyl acetate resin. Examples of the polyvinyl acetate resin include polyvinyl acetate which is a homopolymer of vinyl acetate, and copolymers with other monomers copolymerizable with vinyl acetate.

Examples of the other monomer copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

The saponification degree of the polyvinyl alcohol resin is not particularly limited, but is preferably 85 to 100 mol%, more preferably 95.0 to 99.95 mol%. The degree of saponification can be determined in accordance with JIS K6726-.

The average polymerization degree of the polyvinyl alcohol resin is not particularly limited, but is preferably 100 to 10000, more preferably 1500 to 8000. The average degree of polymerization can be determined in accordance with JIS K6726-.

The content of the polyvinyl alcohol resin in the polarizer is not particularly limited, but it is preferable that the polarizer contains the polyvinyl alcohol resin as a main component. The main component is a polyvinyl alcohol resin content of 50 mass% or more based on the total mass of the polarizer. The content of the polyvinyl alcohol resin is preferably 90 mass% or more with respect to the total mass of the polarizer. The upper limit is not particularly limited, but is usually 99.9 mass% or less.

The polarizer preferably further comprises a dichromatic substance. Examples of the dichromatic substance include iodine and an organic dye (dichromatic organic dye). That is, the polarizer preferably contains polyvinyl alcohol as a main component and contains a dichromatic substance.

The method for producing the polarizer is not particularly limited, and a known method may be mentioned, and a method in which a dichromatic substance is adsorbed to a substrate containing polyvinyl alcohol and stretched may be mentioned.

The thickness of the polarizer is not particularly limited, but is usually 20 μm or less, more usually 15 μm or less, and from the viewpoint of further improving the effect of the present invention, it is preferably 10 μm or less, more preferably less than 10 μm, and still more preferably 5 μm or less. The lower limit is not particularly limited, but is usually 2 μm or more, more usually 3 μm or more. For example, the thickness of the polarizer is preferably 2 to 10 μm.

< optically Anisotropic layer >

The laminate has an optically anisotropic layer. The optically anisotropic layer is a layer formed using a composition containing a polymerizable liquid crystal compound represented by the general formula (I) described later.

Hereinafter, first, the components in the composition for forming the optically anisotropic layer will be described in detail, and then, the method for producing the optically anisotropic layer and the characteristics thereof will be described in detail.

(polymerizable liquid Crystal Compound represented by the general formula (I))

The composition contains a polymerizable liquid crystal compound represented by the general formula (I). The polymerizable liquid crystal compound represented by the general formula (I) is a compound exhibiting liquid crystallinity.

L₁-G₁-D₁-Ar-D₂-G₂-L₂……(I)

In the general formula (I), D₁And D₂Each independently represents a single bond, -O-, -CO-O-, -C (═ S) O-, -CR¹R²-、-CR¹R²-CR³R⁴-、-O-CR¹R²-、-CR¹R²-O-CR³R⁴-、-CO-O-CR¹R²-、-O-CO-CR¹R²-、-CR¹R²-CR³R⁴-O-CO-、-CR¹R²-O-CO-CR³R⁴-、-CR¹R²-CO-O-CR³R⁴-、-NR¹-CR²R³-or-CO-NR¹-。

R¹、R²、R³And R⁴Each independently represents a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms. In the presence of a plurality of R¹、R²、R³And R⁴In the case of each of (1), a plurality of R¹A plurality of R²A plurality of R³And a plurality of R⁴Each may be the same as or different from each other.

G₁And G₂Each independently represents a 2-valent alicyclic hydrocarbon group or aromatic hydrocarbon group having 5 to 8 carbon atoms, and a methylene group contained in the alicyclic hydrocarbon group may be substituted by-O-, -S-, or-NH-.

L₁And L₂Each independently represents an organic group having a valence of 1, selected from the group consisting of L₁And L₂At least 1 of the groups represents a 1-valent group having a polymerizable group.

Ar represents a 2-valent aromatic ring group represented by the following general formula (II-1), general formula (II-2), general formula (II-3) or general formula (II-4).

[ chemical formula 1]

General formula (VII)

In the above general formulae (II-1) to (II-4), Q₁represents-S-, -O-or-NR¹¹-，

R¹¹Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,

Y₁represents an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms (the aromatic hydrocarbon group and the aromatic heterocyclic group may have a substituent),

Z₁、Z₂and Z₃Independently represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 1-valent carbon atom and 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group or-NR¹²R¹³or-SR¹²，

Z₁And Z₂May be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring, R¹²And R¹³Each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms,

A₁and A₂Each independently is selected from the group consisting of-O-, -NR²¹A radical of the group consisting of-S-and-CO-, R²¹Represents a hydrogen atom or a substituent, X represents a hydrogen atom or a group 14 to 16 non-metal atom to which a substituent may be bonded (preferably, examples thereof include ═ O, ═ S, ═ NR ', -C (R') R '(in which R' represents a substituent)),

ax represents an organic group having 2 to 30 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and preferably includes an aromatic hydrocarbon ring group; an aromatic heterocyclic group; an alkyl group having 3 to 20 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring; an alkenyl group having 3 to 20 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring; an alkenyl group having 3 to 20 carbon atoms of at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring,

ay represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms having at least one aromatic ring selected from the group consisting of an aromatic hydrocarbon ring and an aromatic heterocyclic ring, and a preferable mode of the organic group is the same as that of the organic group of Ax,

the aromatic rings in Ax and Ay may have a substituent, respectively, Ax and Ay may be bonded to each other to form a ring,

Q₂represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.

Examples of the substituent include a halogen atom, an alkyl group, a halogenated alkyl group, an alkenyl group, an aryl group, a cyano group, an amino group, a nitro group, a nitroso group, a carboxyl group, an alkylsulfinyl group having 1 to 6 carbon atoms, an alkylsulfonyl group having 1 to 6 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylsulfanyl group having 1 to 6 carbon atoms, an N-alkylamino group having 1 to 6 carbon atoms, an N, N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfamoyl group having 1 to 6 carbon atoms, an N, N-dialkylsulfamoyl group having 2 to 12 carbon atoms, and a combination thereof.

With respect to the definition and preferred ranges of the respective substituents of the liquid crystal compound represented by the general formula (I), with respect to D₁、D₂、G₁、G₂、L₁、L₂、R¹、R²、R³、R⁴、Q₁、Y₁、Z₁And Z₂Reference can be made to D of the compound (A) described in Japanese patent laid-open publication No. 2012-021068¹、D²、G¹、G²、L¹、L²、R⁴、R⁵、R⁶、R⁷、X¹、Y¹、Q¹、Q²In connection with A₁、A₂And X, A of the compound represented by the general formula (I) described in Japanese patent laid-open No. 2008-107767 can be referred to₁、A₂Description of X for Ax, Ay, Q₂Reference may be made to Ax, Ay, Q of the compound represented by the general formula (I) described in International publication No. 2013/018526¹The description is related to. With respect to Z₃Reference can be made to Q in relation to the compound (A) described in Japanese patent laid-open publication No. 2012-021068¹The description of (1).

In particular, as a composition consisting of L₁And L₂The organic radicals represented are each particularly preferably represented by the formula-D₃-G₃-Sp-P₃The group shown.

D₃And D₁The meaning is the same.

G₃Represents a single bond, a 2-valent aromatic or heterocyclic group having 6 to 12 carbon atoms, or a 2-valent alicyclic hydrocarbon group having 5 to 8 carbon atoms, wherein a methylene group contained in the alicyclic hydrocarbon group may be replaced by-O-, -S-or-NR⁷-substituted, wherein R⁷Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

Sp represents a single bond, represented by- (CH)₂)_n-、-(CH₂)_n-O-、-(CH₂-O-)_n-、-(CH₂CH₂-O-)_m、-O-(CH₂)_n-、-O-(CH₂)_n-O-、-O-(CH₂-O-)_n-、-O-(CH₂CH₂-O-)_m、-C(＝O)-O-(CH₂)_n-、-C(＝O)-O-(CH₂)_n-O-、-C(＝O)-O-(CH₂-O-)_n-、-C(＝O)-O-(CH₂CH₂-O-)_m、-C(＝O)-N(R⁸)-(CH₂)_n-、-C(＝O)-N(R⁸)-(CH₂)_n-O-、-C(＝O)-N(R⁸)-(CH₂-O-)_n-、-C(＝O)-N(R⁸)-(CH₂CH₂-O-)_mOr- (CH)₂)_n-O-(C＝O)-(CH₂)_n-C(＝O)-O-(CH₂)_n-a spacer group of the formula. Wherein n represents an integer of 2 to 12, m represents an integer of 2 to 6, and R⁸Represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. and-CH in each of the above groups₂The hydrogen atom of-may be substituted by methyl.

P₃Represents a polymerizable group.

The polymerizable group is not particularly limited, but is preferably a polymerizable group capable of radical polymerization or cationic polymerization.

Examples of the radical polymerizable group include known radical polymerizable groups, and an acryloyl group or a methacryloyl group is preferable. It is known that an acryloyl group is generally polymerized at a high rate, and from the viewpoint of improving productivity, an acryloyl group is preferable, but a methacryloyl group can be similarly used as a polymerizable group for a highly birefringent liquid crystal.

Examples of the cationically polymerizable group include known cationically polymerizable groups, and examples thereof include alicyclic ether groups, cyclic acetal groups, cyclic lactone groups, cyclic thioether groups, spiroorthoester groups, and vinyloxy groups. Among them, an alicyclic ether group or an ethyleneoxy group is preferable, and an epoxy group, an oxetanyl group or an ethyleneoxy group is more preferable.

Examples of particularly preferable polymerizable groups include the following.

[ chemical formula 2]

In the present specification, the "alkyl group" may be any of linear, branched and cyclic groups, and examples thereof include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, an isopentyl group, a neopentyl group, a1, 1-dimethylpropyl group, a n-hexyl group, an isohexyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group and a cyclohexyl group.

Preferred examples of the liquid crystal compound represented by the general formula (I) are shown below, but the liquid crystal compound is not limited thereto.

[ chemical formula 3]

[ chemical formula 4]

[ chemical formula 5]

In the above formula, "+" indicates a bonding position.

II-2-8

[ chemical formula 6]

II-2-9

[ chemical formula 7]

In the formulae II-2-8 and II-2-9, the group adjacent to the acryloyloxy group represents an allyl group (a group in which a methyl group is substituted with a vinyl group), and represents a mixture of positional isomers in which the methyl group is different in position.

[ chemical formula 8]

[ chemical formula 9]

[ chemical formula 10]

[ chemical formula 11]

[ chemical formula 12]

[ chemical formula 13]

[ chemical formula 14]

[ chemical formula 15]

[ chemical formula 16]

[ chemical formula 17]

[ chemical formula 18]

[ chemical formula 19]

[ chemical formula 20]

[ chemical formula 21]

[ chemical formula 22]

The content of the polymerizable liquid crystal compound represented by the general formula (I) in the composition is not particularly limited, but is preferably 50 to 100% by mass, and more preferably 70 to 99% by mass, based on the total solid content in the composition.

The solid content is other components excluding the solvent in the composition, and is calculated as a solid content even if the solid content is liquid.

The composition may contain a liquid crystal compound other than the polymerizable liquid crystal compound represented by the general formula (I). Examples of the other liquid crystal compounds include known liquid crystal compounds (rod-like liquid crystal compounds and discotic liquid crystal compounds). The other liquid crystal compound may have a polymerizable group.

The content of the other liquid crystal compound in the composition is preferably 0 to 50% by mass, more preferably 10 to 40% by mass, based on the total mass of the polymerizable liquid crystal compound represented by the general formula (I).

The other liquid crystal compound is preferably a liquid crystal compound having a cyclohexane ring in which 1 hydrogen atom is partially substituted with a linear alkyl group.

Here, the "cyclohexane ring in which 1 hydrogen atom is substituted with a linear alkyl group" refers to, for example, a cyclohexane ring in which a hydrogen atom of a cyclohexane ring present on the molecular terminal side is substituted with 1 linear alkyl group in the case of having 2 cyclohexane rings, as shown in the following general formula (2).

The compound is, for example, a compound having a structure represented by the following general formula (2), and among them, a compound having a (meth) acryloyl group represented by the following general formula (3) is preferable from the viewpoint of obtaining a laminate excellent in heat resistance.

[ chemical formula 23]

In the general formula (2), a represents a bonding site.

And, in the above general formulae (2) and (3), R²Represents an alkyl group having 1 to 10 carbon atoms, n represents 1 or 2, W¹And W²Each independently represents an alkyl group, an alkoxy group or a halogen atom, and W¹And W²Can be bonded to each other to formA ring structure which may have a substituent.

In the general formula (3), Z represents-COO-, L represents an alkylene group having 1 to 6 carbon atoms, and R³Represents a hydrogen atom or a methyl group.

Examples of the above-mentioned compounds include compounds represented by the following formulae A-1 to A-5. In addition, in the following formula A-3, R⁴Represents an ethyl or butyl group.

[ chemical formula 24]

Examples of the other liquid crystal compounds include compounds represented by the formulae (M1), (M2) and (M3) described in paragraphs [0030] to [0033] of Japanese patent laid-open No. 2014-077068.

(polymerizable monomer)

The composition may further contain another polymerizable monomer other than the polymerizable liquid crystal compound represented by the general formula (I) and another liquid crystal compound having a polymerizable group. Among them, from the viewpoint of further improving the strength of the optically anisotropic layer, a polymerizable compound (polyfunctional polymerizable monomer) having 2 or more polymerizable groups is preferable.

The polyfunctional polymerizable monomer is preferably a polyfunctional radical polymerizable monomer. Examples of the polyfunctional radical polymerizable monomer include polymerizable monomers described in paragraphs [0018] to [0020] in Japanese patent laid-open publication No. 2002-296423.

When the composition contains the polyfunctional polymerizable monomer, the content of the polyfunctional polymerizable monomer is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, and still more preferably 0.1 to 5% by mass, based on the total solid content in the composition.

(polymerization initiator)

The composition may comprise a polymerization initiator.

As the polymerization initiator, a photopolymerization initiator capable of initiating a polymerization reaction by irradiation with ultraviolet rays is preferable.

Examples of the photopolymerization initiator include an α -carbonyl compound (described in U.S. Pat. Nos. 2367661 and 2367670), an acyloin ether (described in U.S. Pat. No. 2448828), an α -hydrocarbon-substituted aromatic acyloin compound (described in U.S. Pat. No. 2722512), a polynuclear quinone compound (described in U.S. Pat. Nos. 3046127 and 2951758), a combination of a triarylimidazole dimer and p-aminophenyl ketone (described in U.S. Pat. No. 3549367), an acridine and phenazine compound (described in Japanese patent publication No. 60-105667 and U.S. Pat. No. 4239850), an oxadiazole compound (described in U.S. Pat. No. 4212970), and an acylphosphine oxide compound (described in Japanese patent publication No. 63-040799, Japanese patent publication No. 5-029234, a naphthoquinone compound, a naphtho, Japanese patent laid-open Nos. H10-095788 and H10-029997).

As the polymerization initiator, an oxime type polymerization initiator is preferable, and a compound represented by the general formula (2) is more preferable.

[ chemical formula 25]

In the above general formula (2), X²Represents a hydrogen atom or a halogen atom.

In the general formula (2), Ar²Represents a 2-valent aromatic group, D⁷Represents a C1-12 organic group with a valence of 2.

And, in the above general formula (2), R¹¹Represents an alkyl group having 1 to 12 carbon atoms, Y²Represents an organic group having a valence of 1.

In the above general formula (2), as X²Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a chlorine atom is preferable.

In the above general formula (2), Ar is²The 2-valent aromatic group represented by (a) includes, for example, aromatic hydrocarbon rings having a benzene ring, a naphthalene ring, an anthracene ring, a phenanthroline ring, and the like; furan ring, pyrrole ring, thiophene ring, pyridine ring, thiazole ringAnd 2-valent groups of aromatic heterocycles such as benzothiazole ring.

In the above general formula (2), D is⁷The organic group having a valence of 2 and having 1 to 12 carbon atoms includes, for example, a linear or branched alkylene group having 1 to 12 carbon atoms, and specifically includes a methylene group, an ethylene group and a propylene group.

In the above general formula (2), R is¹¹Examples of the alkyl group having 1 to 12 carbon atoms include a methyl group, an ethyl group and a propyl group.

In the above general formula (2), Y is²Examples of the 1-valent organic group include those having a benzophenone skeleton ((C)₆H₅)₂CO) functional groups. Specifically, as in the groups represented by the following general formula (2a) and the following general formula (2b), a functional group having a benzophenone skeleton in which a terminal benzene ring is unsubstituted or monosubstituted is preferable. In the following general formulae (2a) and (2b), a bonding position is represented by a bonding position to a carbon atom of a carbonyl group in the general formula (2).

[ chemical formula 26]

Examples of the compound represented by the above general formula (2) include a compound represented by the following formula S-1 and a compound represented by the following formula S-2.

[ chemical formula 27]

The content of the polymerization initiator in the composition is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, relative to the total solid content in the composition.

(solvent)

The composition may contain a solvent from the viewpoint of workability in forming the optically anisotropic layer.

Examples of the solvent include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone), ethers (e.g., dioxane and tetrahydrofuran), aliphatic hydrocarbons (e.g., hexane), alicyclic hydrocarbons (e.g., cyclohexane), aromatic hydrocarbons (e.g., toluene, xylene, and trimethylbenzene), halogenated carbons (e.g., dichloromethane, dichloroethane, dichlorobenzene, and chlorotoluene), esters (e.g., methyl acetate, ethyl acetate, and butyl acetate), water, alcohols (e.g., ethanol, isopropanol, butanol, and cyclohexanol), cellosolves (e.g., methyl cellosolve and ethyl cellosolve), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide), and amides (e.g., dimethylformamide and dimethylacetamide).

One of them may be used alone or 2 or more may be used simultaneously.

(leveling agent)

The composition may contain a leveling agent from the viewpoint of keeping the surface of the optically anisotropic layer smooth.

The leveling agent is preferably a fluorine-based leveling agent or a silicon-based leveling agent because the leveling effect is high with respect to the amount added, and more preferably a fluorine-based leveling agent because bleeding (blooming, bleeding) is less likely to occur.

Examples of the leveling agent include compounds described in paragraphs [0079] to [0102] of Japanese patent laid-open No. 2007-069471, polymerizable liquid crystal compounds represented by the general formula (I) (particularly, compounds described in paragraphs [0020] to [0032 ]) described in Japanese patent laid-open No. 2013-047204, polymerizable liquid crystal compounds represented by the general formula (I) (particularly, compounds described in paragraphs [0022] to [0029 ]) described in Japanese patent laid-open No. 2012-211306, liquid crystal alignment promoters represented by the general formula (I) (particularly, compounds described in paragraphs [0076] to [0078] and [0082] to [0084 ]) described in Japanese patent laid-open No. 2002-129162, and compounds represented by formulae (I), (II) and (III) described in Japanese patent laid-open No. 2005-099248 (particularly, [0092] the compound described in paragraphs [0096 ]). Further, the functional group may also function as an alignment control agent described later.

(alignment controlling agent)

The composition may further comprise an orientation controlling agent, as necessary.

The orientation control agent can form various orientation states such as homeotropic orientation (Vertical orientation), tilt orientation, hybrid orientation, and cholesteric orientation in addition to uniform orientation, and can control and realize a specific orientation state more uniformly and more precisely.

As the orientation control agent for promoting uniform orientation, for example, a low molecular orientation control agent or a high molecular orientation control agent can be used.

As the low-molecular orientation controlling agent, for example, the descriptions of paragraphs [0009] to [0083] of Japanese patent laid-open publication No. 2002-.

Further, as the orientation controlling agent for the polymer, for example, the paragraphs [0021] to [0057] of Japanese patent laid-open No. 2004-198511 and the paragraphs [0121] to [0167] of Japanese patent laid-open No. 2006-106662 are referred to and are incorporated herein by reference.

Examples of the orientation control agent for forming or promoting the vertical orientation include a boric acid compound and an onium salt compound, and specifically, compounds described in paragraphs [0023] to [0032] of Japanese patent laid-open No. 2008-225281, paragraphs [0052] to [0058] of Japanese patent laid-open No. 2012-208397, paragraphs [0024] to [0055] of Japanese patent laid-open No. 2008-026730, and paragraphs [0043] to [0055] of Japanese patent laid-open No. 2016-193869, and the contents thereof are incorporated in the present specification.

In the case where the composition contains an orientation controlling agent, the content of the orientation controlling agent is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, relative to the total solid content in the composition.

(other Components)

The composition may further contain components other than the above-mentioned components, and examples thereof include a surfactant, a tilt angle controlling agent, an orientation assistant, a plasticizer, a crosslinking agent, and the like.

(method for producing optically Anisotropic layer)

The method for producing the optically anisotropic layer is not particularly limited, and known methods can be used.

For example, a cured coating film (optically anisotropic layer) can be produced by applying the composition to a predetermined substrate (for example, a support layer described later) to form a coating film, and subjecting the obtained coating film to a curing treatment (irradiation with an active energy ray (light irradiation treatment) and/or a heating treatment). Further, an alignment film described later may be used as necessary.

The composition can be applied by a known method (for example, a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, and a die coating method).

In the method for producing an optically anisotropic layer, it is preferable that the alignment treatment of the liquid crystal compound contained in the coating film is performed before the curing treatment of the coating film.

The orientation treatment can be performed by drying or heating at room temperature (for example, 20 to 25 ℃). In the case where the liquid crystal phase formed in the alignment treatment is a thermotropic liquid crystal compound, it can be generally transferred in accordance with a change in temperature or pressure. In the case of a liquid crystal compound having lyotropic properties, the amount can be changed depending on the composition ratio such as the amount of the solvent.

When the orientation treatment is a heat treatment, the heating time (heat aging time) is preferably 10 seconds to 5 minutes, more preferably 10 seconds to 3 minutes, and still more preferably 10 seconds to 2 minutes.

The curing treatment (irradiation with an active energy ray (light irradiation treatment) and/or heating treatment) of the coating film described above can also be referred to as a fixing treatment for fixing the alignment of the liquid crystal compound.

Preferably, the immobilization treatment is performed by irradiation with an active energy ray (preferably, ultraviolet ray), and the liquid crystal is immobilized by polymerization of the liquid crystal compound.

(characteristics of optically Anisotropic layer)

The optically anisotropic layer is a film formed using the composition described above.

The optical characteristics of the optically anisotropic layer are not particularly limited, but preferably function as a λ/4 plate.

The λ/4 plate is a plate having a function of converting linearly polarized light of a certain specific wavelength into circularly polarized light (or converting circularly polarized light into linearly polarized light), and refers to a plate (optically anisotropic layer) in which an in-plane retardation Re (λ) at a specific wavelength λ nm satisfies Re (λ) ═ λ/4.

In the formula, it can be achieved at any wavelength in the visible light region (for example, 550nm), but it is preferable that the in-plane retardation Re (550) at a wavelength of 550nm satisfies the relationship of 110 nm. ltoreq. Re (550). ltoreq.160 nm, and more preferably, 110 nm. ltoreq. Re (550). ltoreq.150 nm.

It is preferable that Re (450) which is an in-plane retardation of the optically anisotropic layer measured at a wavelength of 450nm, Re (550) which is an in-plane retardation of the optically anisotropic layer measured at a wavelength of 550nm, and Re (650) which is an in-plane retardation of the optically anisotropic layer measured at a wavelength of 650nm are in the relationship of Re (450). ltoreq.Re (550). ltoreq.Re (650). That is, this relationship can be referred to as a relationship indicating the inverse wavelength dispersion property.

The range of Re (550)/Re (450) is not particularly limited, but is preferably 1.05 to 1.25, more preferably 1.13 to 1.23. The range of Re (650)/Re (550) is not particularly limited, but is preferably 1.01 to 1.25, more preferably 1.01 to 1.10.

The optically anisotropic layer may be an a plate or a C plate, and is preferably a positive a plate.

The positive a plate can be obtained by, for example, horizontally aligning the polymerizable liquid crystal compound represented by the general formula (I).

The optically anisotropic layer may have a single-layer structure or a multi-layer structure. In the case of a multilayer structure, it may be a stack of an a plate (e.g., a positive a plate) and a C plate (e.g., a positive C plate).

In addition, in the case where the optically anisotropic layer is a multilayer structure, each layer corresponds to a layer formed using the above-described composition.

The thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.5 to 10 μm, more preferably 1.0 to 5 μm, from the viewpoint of thinning.

The relationship between the transmission axis of the polarizer and the slow axis of the optically anisotropic layer in the laminate is not particularly limited.

When the laminate is used for antireflection purposes, the optically anisotropic layer is preferably a λ/4 plate, and the angle formed by the transmission axis of the polarizer and the slow axis of the optically anisotropic layer is preferably within a range of 45 ± 10 ° (35 to 55 °).

When the laminate is used for optical compensation of a tilt angle of an IPS (In-Plane-Switching) liquid crystal, the optical anisotropic layer preferably has a multilayer structure of a positive A plate and a positive C plate having λ/4 plates, and the angle formed by the transmission axis of the polarizer and the slow axis of the optical anisotropic layer is In the range of 0 + -10 DEG (-10 DEG to 10 DEG) or 90 + -10 DEG (80 DEG to 100 DEG).

< other layer >

The laminate of the present invention may have other members than the above-described substrate, polarizer, and optically anisotropic layer.

The laminate may also have a polarizer protective film. More specifically, as shown in fig. 2, a laminate 10B as another embodiment of the laminate of the present invention includes a1 st substrate 12A, a1 st polarizer protective film 20A, a polarizer 16, a2 nd polarizer protective film 20B, an optically anisotropic layer 18, and a2 nd substrate 12B in this order. In addition, in fig. 2, the embodiment having 2 polarizer protective films (the 1 st polarizer protective film 20A and the 2 nd polarizer protective film 20B) has been described, but the embodiment is not limited to this, and may be an embodiment having only one of the 1 st polarizer protective film 20A and the 2 nd polarizer protective film 20B.

Among them, the laminate preferably has a polarizer protective film on the surface of the polarizer on the side opposite to the optically anisotropic layer. That is, a laminate obtained by laminating an optically anisotropic layer, a polarizer and a polarizer protective film in this order is preferable. In the above-described embodiment, the laminate may have an adhesive layer or an adhesive layer between the optically anisotropic layer and the polarizer.

The polarizer protective film may have any structure, including, for example, a transparent support or a hard coat layer, or a laminate of a transparent support and a hard coat layer.

As the hard coat layer, a known layer can be used, and for example, a layer obtained by polymerizing and curing a polyfunctional monomer may be used.

As the transparent support, a known transparent support (preferably, a transparent resin support) can be used. Examples of the material forming the transparent support include cellulose resins typified by triacetylcellulose (hereinafter, also referred to as cellulose acylate), norbornene resins (ZEONEX, ZEONOR, ARTON, manufactured by jsrcorporaton, and the like manufactured by Zeon corporation), acrylic resins, polyester resins, and polystyrene resins. Among them, cellulose-based resins and norbornene-based resins are preferable, and norbornene-based resins are more preferable.

The norbornene-based resin is a resin having a norbornene skeleton. More specifically, cycloolefin polymers (COP) and cycloolefin copolymers (COC) can be mentioned.

The thickness of the polarizer protective film is not particularly limited, but is preferably 40 μm or less, more preferably 25 μm or less, from the viewpoint of enabling reduction in the thickness of the polarizing plate. The lower limit is not particularly limited, but is usually 10 μm or more.

The laminate may include an alignment film. The alignment film is a layer having a function of determining an alignment direction of a liquid crystal compound disposed thereon.

The alignment film is generally a film (layer) provided on one surface of the above optically anisotropic layer.

Examples of the alignment film include a rubbing film of a layer containing an organic compound such as a polymer, an inclined vapor deposition film of an inorganic compound, and a film having microgrooves.

The alignment film may be a so-called photo alignment film (photo alignment film) which is an alignment film formed by irradiating a photo-alignment material with polarized light or unpolarized light.

The alignment film is preferably formed by rubbing the surface of a layer containing an organic compound such as a polymer (polymer layer). The rubbing treatment is performed by rubbing the surface of the polymer layer several times in a certain direction (preferably, the longitudinal direction of the support) with paper or cloth. Examples of the polymer used for forming the alignment film include a polyimide resin and a polyvinyl alcohol resin.

The thickness of the alignment film is not particularly limited as long as the film can exhibit an alignment function, but is preferably 0.01 to 5 μm, and more preferably 0.05 to 2 μm.

To ensure adhesion between the layers, the laminate may have an adhesive or bonding layer between the layers.

The laminate may have a transparent support between the layers.

The laminate may further have an optically anisotropic layer other than the optically anisotropic layer formed using the composition containing the polymerizable liquid crystal compound represented by the above general formula (I).

The other optically anisotropic layer may be an a plate or a C plate.

The laminate may include a touch sensor. The structure of the touch sensor is not particularly limited, but an ITO (Indium Tin Oxide) thin film, a silver mesh thin film, a copper mesh thin film, and a silver nanowire thin film of a capacitance system may be used. The laminate may further include a refractive index matching layer so that the ITO electrode is not visible.

< polarizing plate >

The polarizing plate comprises at least the above optically anisotropic layer and a polarizer.

The water content of the polarizing plate was 3.0g/m²Hereinafter, from the viewpoint of obtaining a laminate having more excellent heat resistance, 2.3g/m is preferable²Below, more preferably 1.5g/m²Below, particularly preferably 0.8g/m²The following. The lower limit is not particularly limited, but is usually 0.1g/m²The above.

The method of adjusting the water content of the polarizing plate is not particularly limited, and for example, a method of adjusting the water content of the polarizing plate by leaving the polarizing plate still in a predetermined environment may be mentioned. As described later, a predetermined laminate was obtained by sandwiching a polarizing plate having a predetermined water content between 2 glass plates.

The object of the measurement of the water content is a polarizing plate including an optically anisotropic layer and a polarizer, and including a member located therebetween. For example, in the case where an optically anisotropic layer, an adhesive layer, a polarizer protective film, and a polarizer are arranged in this order, the measurement target of the water content corresponds to a polarizing plate including the optically anisotropic layer, the adhesive layer, the polarizer protective film, and the polarizer.

In the case where a polarizer protective film is disposed on the surface of the polarizer on the side opposite to the optically anisotropic layer side, the polarizing plate including the polarizer protective film is a measurement target of the water content. For example, in the case where an optically anisotropic layer, an adhesive layer, a polarizer protective film, a polarizer, and a polarizer protective film are disposed in this order, the measurement target of the water content corresponds to a polarizing plate including the optically anisotropic layer, the adhesive layer, the polarizer protective film, the polarizer, and the polarizer protective film. For example, in the case where an optically anisotropic layer, an adhesive layer, a polarizer, and a polarizer protective film are disposed in this order, the measurement target of the water content corresponds to a polarizing plate including the optically anisotropic layer, the adhesive layer, the polarizer, and the polarizer protective film.

When other members such as a touch sensor are disposed between 2 substrates in the laminate, the measurement of the water content can be performed using an object to be measured that includes the other members and a polarizing plate, in the case where the other members hardly affect the water content.

The method of measuring the water content is a mass obtained by converting the initial mass of the polarizing plate to be measured and the amount of change in the dry mass after drying at 120 ℃ for 2 hours (initial mass-dry mass) per unit area. For example, when a laminate is produced by holding a polarizing plate in a stationary state under a predetermined environment and adjusting the water content of the polarizing plate and sandwiching the polarizing plate between 2 glass plates, the water content of the polarizing plate immediately before sandwiching the polarizing plate between 2 glass plates can be measured by the above-described method. In addition, when a laminate having 2 substrates and polarizing plates disposed between the 2 substrates is decomposed and the water content of the polarizing plates is measured, the laminate can be decomposed in an environment at a temperature of 25 ℃ and a humidity of 60% within 30 minutes to take out the polarizing plates, and the water content of the polarizing plates can be calculated by the above-described method.

< method for producing laminate >

The method for producing the laminate is not particularly limited, and known methods can be used.

The following methods may be mentioned: first, after an optically anisotropic layer formed on a predetermined support was bonded to a polarizer, the support was peeled off to produce a polarizing plate including the optically anisotropic layer and the polarizer, and the polarizing plate was sandwiched between 2 substrates to produce a laminate by adjusting the water content of the polarizing plate.

In addition, in the production of the polarizing plate, an optically anisotropic layer may be formed directly on the polarizer.

< use >)

The polarizing plate in the laminate of the present invention is useful as an antireflection plate.

More specifically, in the case where the optically anisotropic layer in the polarizing plate is a λ/4 plate, the laminate can be suitably used as an antireflection plate. In particular, as described above, in the case where the optically anisotropic layer in the laminate has a multilayer structure of the positive a plate and the positive C plate, the total Rth of the optically anisotropic layers can be adjusted to be close to zero, and the visibility in the oblique direction can be improved.

In the case where the optically anisotropic layer has a multilayer structure of a positive a plate (preferably a positive a plate functioning as a λ/4 plate) and a positive C plate, the positive a plate may be disposed on the polarizer side, and the positive C plate may be disposed on the polarizer side.

When the laminate is used as an antireflection plate, the laminate can be applied to various image display devices such as a liquid crystal display device, a plasma display panel, an organic electroluminescence device, and a cathode ray tube display device.

The optically anisotropic layer in the laminate of the present invention is useful as an optical compensation film.

The optical compensation film can be suitably used for optical compensation of a liquid crystal display device, and can improve color tone change in viewing from an oblique direction and light leakage in black display. For example, an optical compensation film can be provided between a polarizer and a liquid crystal cell of an IPS liquid crystal display device. In particular, in optical compensation of IPS liquid crystal, the optically anisotropic layer in the laminate includes a positive a plate and a positive C plate, whereby a large effect can be obtained.

In the case where the optically anisotropic layer has a multilayer structure of a positive a plate (preferably a positive a plate functioning as a λ/4 plate) and a positive C plate, the positive a plate may be disposed on the polarizer side, and the positive C plate may be disposed on the polarizer side. In the case where the polarizer, the positive a plate, and the positive C plate are arranged in this order, the angle formed by the slow axis of the positive a plate and the absorption axis of the polarizer is preferably in the range of 90 ° ± 10 °. When the polarizer, the positive C plate, and the positive a plate are arranged in this order, the slow axis of the positive a plate is preferably parallel to the absorption axis of the polarizer.

The positive a plate and the positive C plate preferably exhibit reverse wavelength dispersibility.

< organic electroluminescent device, liquid crystal display device >

The laminate can be preferably used for an organic electroluminescence device (preferably, an organic EL (electroluminescence) display device) and a liquid crystal display device.

(organic EL display device)

As an example of the organic EL display device of the present invention, a preferred embodiment includes a laminate and an organic EL display panel of the present invention in this order from the viewing side. The optically anisotropic layer included in the laminate is preferably disposed on the organic EL display panel side of the polarizer. In this case, the polarizing plate may be used as a so-called antireflection plate.

In the laminate of the present invention, the substrate disposed on the organic EL display panel side among the 2 substrates can function as a sealing layer of the organic EL display panel. For example, when the substrate is a glass substrate, the glass substrate disposed on the organic EL display panel side among the 2 glass substrates in the laminate of the present invention can function as so-called sealing glass.

An organic EL display panel is a display panel including organic EL elements in which an organic light-emitting layer (organic electroluminescent layer) is interposed between electrodes (between a cathode and an anode). The structure of the organic EL display panel is not particularly limited, and a known structure can be adopted.

Among them, as an organic EL display device including a laminate, there is a mode of an organic EL display device for a smartphone or a tablet pc, and as a configuration corresponding to the laminate, a cover glass/(touch sensor)/(polarizer protective film)/polarizer/(polarizer protective film)/optically anisotropic layer/(touch sensor)/glass for organic EL sealing, a high barrier film, or an organic EL barrier film is assumed. In addition, the component representations represented by () in the above structure may be absent.

(liquid Crystal display device)

The liquid crystal display device of the present invention is an example of an image display device, and includes the laminate of the present invention and the liquid crystal layer.

In the present invention, among the polarizing plates provided on both sides of the liquid crystal layer, the polarizing plate in the laminate of the present invention is preferably used as the front polarizing plate, and more preferably, the polarizing plate in the laminate of the present invention is used as the front and rear polarizing plates. The optically anisotropic layer included in the polarizing plate is preferably disposed on the liquid crystal layer side of the polarizer. In this case, the optically anisotropic layer can be suitably used as an optical compensation film.

In the laminate of the present invention, the substrate disposed on the liquid crystal layer side among the 2 substrates may function as a substrate disposed on both sides of the liquid crystal layer. For example, when the substrates are glass substrates, the glass substrate disposed on the liquid crystal side among the 2 substrates in the laminate of the present invention can function as a glass substrate in a liquid crystal cell composed of a liquid crystal layer and the 2 glass substrates sandwiching the liquid crystal layer.

Among them, as a liquid crystal display device including a laminate, a mode of an IPS liquid crystal display device for smart phones and tablet personal computers can be cited, and as a configuration corresponding to the laminate, cover glass/(touch sensor)/(polarizer protective film)/polarizer/(polarizer protective film)/optically anisotropic layer/glass for liquid crystal cell is assumed. In addition, the component representations represented by () in the above structure may be absent.

The liquid crystal display device is preferably a VA (Vertical Alignment: Vertical Alignment) mode, an OCB (optically compensated Bend) mode, an IPS mode, an FFS (Fringe Field Switching) mode, or a TN (Twisted Nematic) mode, but is not limited thereto.

Like the IPS mode, the FFS mode is switched to a mode in which liquid crystal molecules are always horizontal to the surface of the liquid crystal layer, and is considered to be one of the IPS modes in the present invention.