JP2018070688A - Side-chain type liquid crystal polymer, liquid crystal composition, retardation film, production method of retardation film, laminate for transfer, optical member, and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a side-chain type liquid crystal polymer suitable for the production of a retardation film excellent in heat resistance, a liquid crystal composition, a retardation film, a production method of a retardation film, a laminate for transfer, an optical member, and a polymer to be used for a display device.SOLUTION: The side-chain type liquid crystal polymer comprises a copolymer that has a main chain comprising a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain including a moiety showing liquid crystallinity, and that has a polymerizable group in at least one position selected from a side chain of any structural units in the main chain and terminals of the main chain. Preferably, a structural unit (C) including the polymerizable group comprises a structural unit represented by formula (III).SELECTED DRAWING: None

Description

  The present disclosure relates to a side-chain liquid crystal polymer, a liquid crystal composition, a retardation film, a method for producing a retardation film, a transfer laminate, an optical member, and a display device.

  In a light-emitting display device such as an organic light-emitting display device, a metal electrode having excellent reflectivity is provided in order to efficiently use light from a light-emitting layer. On the other hand, since the external light reflection is increased by using the metal electrode, the light emitting display device includes a circularly polarizing plate for suppressing the external light reflection.

  The light transmitted through the polarizing plate has optical anisotropy, and in the display device, the anisotropy causes a decrease in contrast due to a viewing angle. On the other hand, a technique for improving the viewing angle by using a retardation film, particularly a positive C type retardation film (positive C plate) is known.

The positive C plate can be obtained, for example, by aligning rod-like liquid crystal molecules in the plate perpendicularly to the plate surface.
For example, Patent Document 1 discloses a retardation having a homeotropic alignment liquid crystal film formed from a homeotropic alignment liquid crystalline composition containing a specific homeotropic alignment side chain type liquid crystal polymer and a photopolymerizable liquid crystal compound. A plate is disclosed.

JP 2003-149441 A

  Embodiments of the present disclosure include a side-chain liquid crystal polymer suitable for producing a retardation film having excellent heat resistance, a liquid crystal composition containing the side-chain liquid crystal polymer, a retardation film having a retardation layer having excellent heat resistance, It aims at providing the manufacturing method of the said phase difference film, the laminated body for transfer which transfers the phase difference layer excellent in heat resistance, the optical member containing the said phase difference layer, and the display apparatus containing the said phase difference layer.

  One embodiment of the present disclosure has a main chain including a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity, Provided is a side chain type liquid crystal polymer comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of a side chain of any constituent unit in the main chain and a terminal of the main chain.

  One embodiment of the present disclosure provides a side chain type liquid crystal polymer in which the copolymer includes a structural unit (C) having a side chain including the polymerizable group.

  One embodiment of the present disclosure provides a side-chain liquid crystal polymer in which the structural unit (C) includes the polymerizable group at the end of the side chain.

  One embodiment of the present disclosure provides a side-chain liquid crystal polymer in which the structural unit (C) includes a structural unit represented by the following general formula (III).

(In General Formula (III), R ²¹ represents a hydrogen atom or a methyl group, and R ²² represents — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —C ₂ H ₄ —. L ² represents a direct bond or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—. _{NH -, - COO-CH 2} -CH (OH) -, - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{OCO -, - O-CH 2} -CH (OH) -, - CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{O -, - NH-CH 2} -CH (OH) -, - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) - _{, -CH (NH 2) -CH 2} -NH -, - O -, - NH -, - S-CO-NH -, - NH-CO-S -, - S-CO -, - CO-S-, _{-S -, - S-CH 2} -CH (OH) -, - CH (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 R represents a linking group represented by —S—, —CH (OH) —, or —CH (NH ₂ ) —, and R ²³ represents — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O). _{n ′} —C ₂ H ₄ — represents a group, R ²⁴ represents a hydrogen atom or a methyl group, and m and m ′ are each independently an integer of 0 or more and 20 or less. Each is independently an integer of 1 to 8.)

  One embodiment of the present disclosure contains a side-chain liquid crystal polymer, a polymerizable liquid crystal compound, and a photopolymerization initiator, and the side-chain liquid crystal polymer is a non-liquid crystalline and non-polymerizable structural unit (A ) And a liquid crystalline structural unit (B) having a side chain containing a portion exhibiting liquid crystallinity, the group consisting of the side chain of any structural unit in the main chain and the end of the main chain A liquid crystal composition comprising a copolymer having a polymerizable group at at least one position selected from:

  One embodiment of the present disclosure provides a liquid crystal composition in which the copolymer has a structural unit (C) having a side chain containing the polymerizable group.

  One embodiment of the present disclosure provides a liquid crystal composition in which the structural unit (C) includes the polymerizable group at the end of a side chain.

  One embodiment of the present disclosure provides a liquid crystal composition in which the structural unit (C) includes a structural unit represented by the following general formula (III).

(In General Formula (III), R ²¹ represents a hydrogen atom or a methyl group, and R ²² represents — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —C ₂ H ₄ —. L ² represents a direct bond or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—. _{NH -, - COO-CH 2} -CH (OH) -, - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{OCO -, - O-CH 2} -CH (OH) -, - CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{O -, - NH-CH 2} -CH (OH) -, - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) - _{, -CH (NH 2) -CH 2} -NH -, - O -, - NH -, - S-CO-NH -, - NH-CO-S -, - S-CO -, - CO-S-, _{-S -, - S-CH 2} -CH (OH) -, - CH (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 R represents a linking group represented by —S—, —CH (OH) —, or —CH (NH ₂ ) —, and R ²³ represents — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O). _{n ′} —C ₂ H ₄ — represents a group, R ²⁴ represents a hydrogen atom or a methyl group, and m and m ′ are each independently an integer of 0 or more and 20 or less. Each is independently an integer of 1 to 8.)

  One embodiment of the present disclosure is a retardation film having a retardation layer, wherein the retardation layer contains a side-chain liquid crystal polymer and a polymerizable liquid crystal compound, and the side-chain liquid crystal polymer is A main chain having a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain containing a portion exhibiting liquid crystallinity, and any structure in the main chain Provided is a retardation film comprising a cured product of a liquid crystal composition, comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of side chains of units and terminals of main chains.

  One embodiment of the present disclosure includes the step of forming a retardation layer by polymerizing a side-chain liquid crystal polymer and a polymerizable liquid crystal compound after forming the liquid crystal composition of the above embodiment and aligning the liquid crystal. A method for producing a retardation film is provided.

  One embodiment of the present disclosure includes a retardation layer and a support that releasably supports the retardation layer, and the retardation layer includes a side-chain liquid crystal polymer and a polymerizable liquid crystal compound. The side chain type liquid crystal polymer has a main chain including a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity. A position consisting of a cured product of a liquid crystal composition comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of a side chain of any constituent unit in the main chain and an end of the main chain. Provided is a transfer laminate for use in transferring a phase difference layer.

  1 embodiment of this indication provides an optical member provided with a polarizing plate in the phase contrast film of the above-mentioned embodiment.

  One embodiment of the present disclosure provides a display device including the retardation film of the above embodiment or the optical member of the above embodiment.

  According to an embodiment of the present disclosure, a side-chain liquid crystal polymer suitable for producing a retardation layer having excellent heat resistance, a liquid crystal composition including the side-chain liquid crystal polymer, and a retardation having a retardation layer having excellent heat resistance A film, a method for producing the retardation film, a transfer laminate that transfers a retardation layer having excellent heat resistance, an optical member including the retardation layer, and a display device including the retardation layer can be provided.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a retardation film. FIG. 2 is a schematic cross-sectional view showing one embodiment of a retardation film. FIG. 3 is a schematic cross-sectional view showing one embodiment of a retardation film. FIG. 4 is a schematic cross-sectional view showing an embodiment of a transfer laminate. FIG. 5 is a schematic cross-sectional view showing an embodiment of a transfer laminate. FIG. 6 is a schematic cross-sectional view showing an embodiment of a transfer laminate. FIG. 7 is a schematic cross-sectional view showing one embodiment of the optical member. FIG. 8 is a schematic cross-sectional view showing one embodiment of a display device.

Hereinafter, embodiments and examples of the present disclosure will be described with reference to the drawings and the like. However, the present disclosure can be implemented in many different modes, and should not be construed as being limited to the description of the embodiments and examples illustrated below. In addition, the drawings may be schematically represented with respect to the width, thickness, shape, and the like of each part in comparison with actual aspects for clarity of explanation, but are merely examples, and the interpretation of the present disclosure may be interpreted. It is not limited. In addition, in the present specification and each drawing, elements similar to those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description may be omitted as appropriate. Further, for convenience of explanation, the description may be made using the terms “upper” or “lower”, but the vertical direction may be reversed.
In this specification, when a certain configuration such as a certain member or a certain region is “above (or below)” another configuration such as another member or another region, unless otherwise specified This includes not only when directly above (or directly below) other configurations, but also when above (or below) other configurations, i.e. This includes cases where components are included.

In the present disclosure, the alignment regulating force refers to an action of aligning liquid crystal compounds in the retardation layer in a specific direction.
In the present disclosure, (meth) acryl represents each of acryl or methacryl, (meth) acrylate represents each of acrylate or methacrylate, and (meth) acryloyl group represents each of acryloyl group or methacryloyl group. Represents.
Further, in the present specification, the terms “plate”, “sheet”, and “film” are not distinguished from each other only based on the difference in designations, and are referred to as “film surface (plate surface, sheet surface)”. Is a surface that coincides with the plane direction of the target film-like member (plate-like member, sheet-like member) when the target film-like (plate-like, sheet-like) member is viewed overall and globally. Refers to that.

A. Liquid crystal composition The liquid crystal composition of the present disclosure contains a side-chain liquid crystal polymer, a polymerizable liquid crystal compound, and a photopolymerization initiator, and the side-chain liquid crystal polymer has a non-liquid crystalline and non-polymerizable configuration. Having a main chain comprising a unit (A) and a liquid crystalline structural unit (B) having a side chain containing a liquid crystalline moiety, and the side chain of any structural unit in the main chain and the end of the main chain A liquid crystal composition comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of:

  The liquid crystal composition of the present disclosure can form a retardation layer having high heat resistance by introducing a polymerizable group into a side-chain liquid crystal polymer that is a component of the liquid crystal composition.

About the effect | action which the said liquid-crystal composition exhibits such an effect, it estimates as follows.
It is presumed that the liquid crystal composition is aligned on the substrate and then cured by light irradiation, whereby the polymerizable liquid crystal compound is firmly cross-linked with the side chain liquid crystal polymer and the heat resistance is increased. That is, a side chain type liquid crystal polymer having a polymerizable group and a polymerizable liquid crystal compound undergo a copolymerization reaction, whereby a bond network develops in the cured product of the liquid crystal composition. As a result, the liquid crystal composition It is estimated that phase difference fluctuations can be suppressed when exposed to high temperatures.

  The liquid crystal composition in the present disclosure contains at least a side-chain type liquid crystal polymer, a polymerizable liquid crystal compound, and a photopolymerization initiator, and may further contain other components as long as the effects thereof are not impaired. Hereinafter, each component which comprises a liquid-crystal composition is demonstrated in order.

1. Side Chain Type Liquid Crystal Polymer The side chain type liquid crystal polymer of the present disclosure comprises a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity. And a copolymer having a polymerizable group at least at one position selected from the group consisting of a side chain of any structural unit in the main chain and an end of the main chain.

  Having a polymerizable group in the side chain of any structural unit in the main chain means that the copolymer has a polymerizable group described later in addition to the structural units (A) and (B). It shows containing the structural unit (C) which has a side chain to contain. In addition, having a polymerizable group at the end of the main chain indicates that the constituent unit located at the end of the main chain further has a polymerizable group at the terminal portion.

As long as the effect of the copolymer is not impaired, the constitutional units (A) and (B), the constitutional unit (C) having a side chain containing a polymerizable group, which will be described later, and other other constitutions are included. You may have a unit.
Hereinafter, each part in the copolymer will be described.

(1) Non-liquid crystalline and non-polymerizable structural unit (A)
The non-liquid crystalline and non-polymerizable structural unit (A) is a structural unit having a non-liquid crystalline and non-polymerizable side chain such as an alkyl group, and a side chain type liquid crystal is obtained by the action of the structural unit (A). When the polymer is in a liquid crystal state, the mesogens (parts exhibiting liquid crystal properties) of the liquid crystalline structural unit (B) are homeotropically aligned. The structural unit (A) is preferably at least one selected from the group consisting of structural units represented by the following general formula (I) from the viewpoint of good vertical alignment.

(In General Formula (I), R ¹ is a hydrogen atom or a methyl group, and R ² is represented by — (CH ₂ ) _m —R ³ or — (C ₂ H ₄ O) _n —R ^4. R ³ represents a methyl group which may have a substituent, an aryl group which may have a substituent, or —OR ⁵ , and R ⁴ and R ⁵ each independently represents a substituent. An alkyl group which may have a substituent or an aryl group which may have a substituent, m is an integer of 1 to 22, and n is an integer of 1 to 8.

R ² represents — (CH ₂ ) _m —R ³ or — (C ₂ H ₄ O) _n —R ⁴ , and among them, — (CH ₂ ) _m —R from the viewpoint of good vertical alignment. ³ is preferred. M is an integer of 1 or more and 22 or less, preferably an integer of 1 or more and 17 or less. N is an integer of 1 or more and 8 or less, preferably 2 or more and 8 or less.

Examples of the substituent that the methyl group in R ³ may have include halogen atoms such as a fluorine atom, a chlorine atom, and a bromine atom.
The alkyl group for R ⁴ and R ⁵ may be linear, branched or cyclic, but is preferably linear.
As an alkyl group in R ⁴ and R ^5, an alkyl group having 1 to 20 carbon atoms is preferable, and specifically, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Linear alkyl groups such as n-hexyl group, n-octyl group and n-decyl group, branched alkyl groups such as i-propyl group, i-butyl group and t-butyl group, 1-propenyl group, 1 -Alkenyl group such as butenyl group, alkynyl group such as ethynyl group, 2-propynyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, norbornyl group, adamantyl group, etc. And cycloalkenyl groups such as 1-cyclohexenyl group. In the case of the cycloalkyl group, a cycloalkyl group in which a linear alkyl group is substituted is preferable.

Examples of the substituent that the alkyl group in R ⁴ and R ⁵ may have include a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom, a cyano group, a hydroxyl group, an alkoxy group, and a nitro group. . Of these, halogen atoms such as fluorine atom, chlorine atom and bromine atom are preferable.

The alkyl group in R ⁴ and R ⁵ is not particularly limited, but an alkyl group having 1 to 12 carbon atoms is preferable from the viewpoint of bending resistance and in-plane uniformity of retardation.

The aryl group in R ³ , R ⁴ , and R ⁵ is preferably an aryl group having 6 to 20 carbon atoms, and specifically includes a phenyl group, a naphthyl group, an anthracenyl group, etc. Among them, a phenyl group or A naphthyl group is preferred, and a phenyl group is more preferred.

Examples of the substituent that the aryl group in R ³ , R ⁴ , and R ⁵ may have include, for example, a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom, a cyano group, a hydroxyl group, an alkyl group, and an alkoxy group. , A nitro group, and the like. Examples of the alkyl group include those having 1 to 12 carbon atoms, and those having 1 to 9 carbon atoms, which may be linear alkyl groups, branched or ring structures. It may be an alkyl group containing Of these, halogen atoms such as fluorine atom, chlorine atom and bromine atom, and alkyl groups having 1 to 9 carbon atoms are preferable. Specific examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, cyclopentyl group, cyclohexyl group, cyclohexylmethyl group, cyclohexyl group. Examples thereof include an ethyl group and a cyclohexylpropyl group. The hydrogen atom of the alkyl group may be substituted with a halogen atom.

The non-liquid crystalline and non-polymerizable structural unit (A) possessed by the copolymer may be one type or two or more types.
Specific examples of the structural unit represented by the general formula (I) include the following chemical formulas (I-1) to (I-10).

  For the synthesis of the copolymer, a (meth) acrylic acid ester derivative that induces the structural unit (A) can be used as a monomer. The (meth) acrylic acid ester derivative which derives the structural unit (A) can be used alone or in combination of two or more.

As the content ratio of the structural unit (A) in the copolymer, the structural unit contained in the entire copolymer is from the viewpoint of improving the vertical alignment of the liquid crystalline structural unit (B) and having sufficient liquid crystal alignment. When the amount is 100 mol%, it is preferably set within the range of 10 mol% to 60 mol%, more preferably within the range of 10 mol% to 40 mol%, It is preferable to set within the range of mol% or more and 35 mol% or less, and particularly preferably within the range of 20 mol% or more and 30 mol% or less.
In addition, the content rate of each structural unit in a copolymer can be computed from the integrated value by < ¹ > H-NMR measurement.

(2) Liquid crystalline structural unit (B) having a side chain containing a portion exhibiting liquid crystallinity
The liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity is a structural unit having a side chain including a mesogen (portion exhibiting liquid crystallinity). In the present disclosure, the mesogen means that it has two or more ring structures, preferably three or more ring structures, and the ring structures are linked by a direct bond, or the ring structure contains 1 atom to 3 atoms. This is a partial structure connected through a relatively high rigidity. When the liquid crystalline structural unit (B) has such a mesogen (portion exhibiting liquid crystallinity) in the side chain, the liquid crystalline structural unit (B) is easily vertically aligned.

The ring structure may be an aromatic ring such as benzene, naphthalene or anthracene, or may be a cyclic aliphatic hydrocarbon such as cyclopentyl or cyclohexyl.
In the case where the ring structure is connected through 1 atom to 3 atoms, the structure of the connection part is -O-, -S-, -OC (= O)-, -C (= O) —O—, —O—C (═O) —O—, —NR′—C (═O) —, —C (═O) —NR′—, —O—C (═O) —NR '-, -NR'-C (= O) -O-, -NR'-C (= O) -NR'-, -O-NR'-, or -NR'-O-, -C = C- , -N = N- and the like (R 'is a hydrogen atom or a methyl group).
Among them, the mesogen is preferably a rod-shaped mesogen in which the ring structure is connected at the para position.

Moreover, it is preferable that the terminal of the side chain of the said liquid crystalline structural unit (B) is a polar group or has an alkyl group or an alkoxy group from the viewpoint of vertical alignment. Specific examples of the polar _{group, -F, -Cl, -CN, -OCF} 3, -OCF 2 H, -NCO, -NCS, -NO 2, -NHC (= O) -R '', —C (═O) —OR ″, —OH, —SH, —CHO, —SO ₃ H, or —NR ″ ₂ (R ″ is a hydrogen atom or a hydrocarbon group) and the like can be mentioned.
Examples of the alkyl group include linear, branched or cyclic alkyl groups having 1 to 6 carbon atoms. Examples of the alkoxy group include linear, branched or cyclic alkoxy groups having 1 to 6 carbon atoms.
The liquid crystalline structural unit (B) is preferably at least one selected from the group consisting of structural units represented by the following general formula (II) from the viewpoint of vertical alignment.

(In General Formula (II), R ¹¹ represents a hydrogen atom or a methyl group, R ¹² represents a group represented by — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —, ¹ is a direct bond, or a linking group represented by —O—, —O—C (═O) —, or —C (═O) —O—, and Ar ¹ has a substituent. Or an arylene group having 6 to 10 carbon atoms, and a plurality of L ¹ and Ar ¹ may be the same or different, and R ¹³ represents —F, —Cl, —CN, —OCF _{3. ^{, -OCF 2 H, -NCO, -NCS}} , -NO 2, -NHC (= O) -R 14, -C (= O) -OR 14, -OH, -SH, -CHO, -SO 3 H, —NR ¹⁴ ₂ , —R ¹⁵ , or —OR ¹⁵ , R ¹⁴ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ¹⁵ represents Represents an alkyl group having 1 to 6 carbon atoms, a is an integer of 2 to 4 and m and n are each independently an integer of 2 to 10.

In the general formula (II), a site formed by connecting 2 or more and 4 or less of -L ¹ -Ar ^1- is a mesogen.

M and n of R ^{12 in} the general formula (II) are each independently an integer of 2 or more and 10 or less. From the standpoint of vertical alignment, among them, m and n are preferably 2 or more and 8 or less, and more preferably 2 or more and 6 or less.

R ¹³ in the general formula (II) is —F, —Cl, —CN, —OCF ₃ , —OCF ₂ H, —NCO, —NCS, —NO ₂ , —NHC (═O) —R ¹⁴ , —C (═O) —OR ¹⁴ , —OH, —SH, —CHO, —SO ₃ H, —NR ¹⁴ ₂ , —R ¹⁵ , or —OR ¹⁵ , and among them, —Cl— _{,, -CN, -OCF 3, -OCF} 2 H, -NCO, -NCS, -NO 2, -NHC (= O) -R 14, -C (= O) -OR 14, -OH, -SH - CHO, —SO ₃ H, or —NR ¹⁴ ₂ is preferable, and —Cl, —CN, —OCF _3, or —C (═O) —OR ¹⁴ is more preferable.

L ¹ is a direct bond or a linking group represented by —O—, —O—C (═O) —, —C (═O) —O— from the viewpoint of imparting vertical alignment. Is preferred. L ¹ between two Ar ¹ is preferably a direct bond or a linking group represented by —O—C (═O) — or —C (═O) —O—. .

Examples of the arylene group having 6 to 10 carbon atoms that may have a substituent in Ar ¹ include a phenylene group and a naphthylene group, and among them, a phenylene group is more preferable. Examples of the substituent other than R ¹³ that the arylene group may have include an alkyl group having 1 to 5 carbon atoms, a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom.

The alkyl group having 1 to 6 carbon atoms of R ¹⁴ and R ¹⁵ may be linear, branched or cyclic, for example, methyl group, ethyl group, n-propyl group, n-butyl. Group, linear alkyl group such as n-pentyl group and n-hexyl group, branched alkyl group such as i-propyl group, i-butyl group, t-butyl group and 2-methylbutyl group, cyclopropyl group, cyclobutyl Group, a cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, and the like. Among them, an alkyl group having 1 to 5 carbon atoms is preferable.

  As the liquid crystalline structural unit (B), at least one selected from the group consisting of structural units represented by the following general formulas (II-1) to (II-3) is preferable because of excellent vertical alignment. Furthermore, at least one selected from the group consisting of structural units represented by the following general formulas (II-1) to (II-2) is preferable.

Here, the structural unit represented by the above general formula (II-1) ~ (II -3), R 12 ^and, respectively ^{R 13, R 12} in the general formula (II) ^and, similarly to ^{R 13} It is.

  1 type may be sufficient as the liquid crystalline structural unit (B) which a copolymer has, and 2 or more types may be sufficient as it.

  For the synthesis of the copolymer, a (meth) acrylic acid ester derivative that induces the liquid crystalline structural unit (B) can be used as a monomer. The monomer of the (meth) acrylic acid ester derivative which induces the liquid crystalline structural unit (B) can be used alone or in combination of two or more.

As the content ratio of the liquid crystalline structural unit in the copolymer, the vertical alignment of the liquid crystalline structural unit (B) is improved, and from the point of having sufficient liquid crystal alignment, the structural unit contained in the entire copolymer is When the amount is 100 mol%, it is preferably set within the range of 40 mol% or more and 90 mol% or less, more preferably set within the range of 40 mol% or more and 80 mol% or less, and further 45 mol%. It is preferably set within the range of 70 mol% or less, and particularly preferably within the range of 50 mol% or more and 65 mol% or less.
In addition, the content rate of each structural unit in a copolymer can be computed from the integrated value by < ¹ > H-NMR measurement.

(3) Site having a polymerizable group The side chain type liquid crystal polymer of the present disclosure has a polymerizable group at at least one position selected from the group consisting of the side chain of one of the constituent units in the main chain and the end of the main chain. The copolymer which has this is included.

  The polymerizable group of the copolymer reacts with and bonds to the polymerizable group of the polymerizable liquid crystal compound to be described later, thereby curing the liquid crystal composition containing the side chain liquid crystal polymer and the polymerizable liquid crystal compound. It has the role of increasing the bonding network and increasing the heat resistance of the cured product.

The position of the polymerizable group may be a side chain of any constituent unit in the main chain of the side chain type liquid crystal polymer, may be a terminal of the main chain, or may be both of them. Good.
Here, the case of having a polymerizable group in the side chain of any structural unit in the main chain means that the copolymer has a structural unit (C) having a side chain containing a polymerizable group described later. It shows that.

As long as the polymerizable group can react with the polymerizable group of the polymerizable liquid crystal compound, it may react with any polymerization method such as light or thermal radical polymerization, anionic polymerization, and cationic polymerization.
Examples of such polymerizable groups include cyclic ether-containing groups such as oxirane rings and oxetane rings, and ethylenic double bond-containing groups, among others, because they exhibit photocurability and are excellent in handleability. An ethylenic double bond-containing group is preferable. Examples of the ethylenic double bond-containing group include a vinyl group, an allyl group, and a (meth) acryloyl group. Among them, a (meth) acryloyl group is preferable.
Since polymerizable liquid crystal compounds having an ethylenic double bond-containing group as a polymerizable group are widely used, both the polymerizable liquid crystal compound and the side-chain liquid crystal polymer of the present disclosure contain an ethylenic double bond. It preferably has a group.

(3-1) Structural unit (C) having a side chain containing a polymerizable group
The structural unit (C) having a side chain containing a polymerizable group reacts and bonds with the polymerizable group of the polymerizable liquid crystal compound described below, thereby liquid crystal containing a side chain type liquid crystal polymer and the polymerizable liquid crystal compound. A structural unit that increases the bond network in the cured product of the composition.
From the viewpoint of enhancing heat resistance, it is preferable that a polymerizable group is included at the end of the side chain of the structural unit (C).

  Specific examples of the structure of the structural unit (C) having a side chain containing a polymerizable group include a structure selected from the group consisting of structural units represented by the following general formula (III).

(In General Formula (III), R ²¹ represents a hydrogen atom or a methyl group, and R ²² represents — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —C ₂ H ₄ —. L ² represents a direct bond or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—. _{NH -, - COO-CH 2} -CH (OH) -, - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{OCO -, - O-CH 2} -CH (OH) -, - CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{O -, - NH-CH 2} -CH (OH) -, - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) - _{, -CH (NH 2) -CH 2} -NH -, - O -, - NH -, - S-CO-NH -, - NH-CO-S -, - S-CO -, - CO-S-, _{-S -, - S-CH 2} -CH (OH) -, - CH (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 R represents a linking group represented by —S—, —CH (OH) —, or —CH (NH ₂ ) —, and R ²³ represents — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O). _{n ′} —C ₂ H ₄ — represents a group, R ²⁴ represents a hydrogen atom or a methyl group, and m and m ′ are each independently an integer of 0 or more and 20 or less. Each is independently an integer of 1 to 8.)

R ²² represents — (CH ₂ ) _m — or — (C ₂ H ₄ O) _n —C ₂ H ₄ —, and among them, — (CH ₂ ) _m — is preferable.

L ² is a direct bond, or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—NH—, —COO. _{-CH 2 -CH (OH) -,} - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 -OCO -, - O _{-CH 2 -CH (OH) -,} -CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 -O -, - NH _{-CH 2 -CH (OH) -,} - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 -NH -, - O -, - NH -, - S -CO-NH -, - NH-CO-S -, - S-CO -, - CO-S -, - S -, - S-CH 2 - _{CH (OH) -, - CH} (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 -S -, - CH (OH) - , or -CH (NH ₂₎ - is a linking group represented, among others, --OCO-NH- are preferred.

R ²³ represents a group represented by — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O) _{n ′} —C ₂ H ₄ —, among which — (CH ₂ ) _{m ′} — represents preferable.

  The structural unit (C) possessed by the copolymer may be one type or two or more types.

The content ratio of each structural unit in the copolymer when the copolymer contains the structural unit (C) is as follows. When the amount of the structural unit contained in the entire copolymer is 100 mol%, the structural unit (C ) Can be set within the range of 2.5 mol% or more and 40 mol% or less, and is preferably set within the range of 5 mol% or more and 35 mol% or less. It is preferable to set within a range of from mol% to 30 mol%. If the content ratio of the structural unit (C) is too small, the amount of bonding between the side chain type liquid crystal polymer and the polymerizable liquid crystal compound becomes insufficient, and sufficient heat resistance may not be obtained. If the content ratio of is too large, the liquid crystal orientation and solubility may decrease.
Even when the copolymer contains the structural unit (C) and further contains a polymerizable group at the end of the main chain, the preferred content of the structural unit (C) is the same as the above-described ratio.
In addition, the content rate of each structural unit in a copolymer can be computed from the integrated value by < ¹ > H-NMR measurement.

For the synthesis of the copolymer having the structural unit (C), the structural unit (C ′) corresponding to the precursor structure of the structural unit (C), that is, a reactive functional group capable of introducing a polymerizable group. A (meth) acrylic acid ester derivative that induces a structural unit (C ′) having a side chain containing can be used as a polymerizable group-introducing precursor monomer. The said polymerizable group introduction | transduction precursor monomer can be used individually by 1 type or in combination of 2 or more types.
As the polymerizable group-introducing precursor monomer, a (meth) acrylic acid ester derivative having a reactive functional group capable of introducing a polymerizable group, although not reactive with an ethylenic double bond, is used. Can do.
By using such a polymerizable group-introduced precursor monomer, first, the main chain of the copolymer is synthesized, and then the functional group present in the side chain of the structural unit (C ′) contained in the main chain and the functional group A polymerizable group is introduced by reacting a polymerizable group introducing agent having a polymerizable group and a functional group that reacts with the group to form a bond.
As a combination of a functional group having reactivity capable of introducing a polymerizable group (functional group having a side chain of a structural unit) and a functional group that reacts with the functional group (polymerizable functional group introducing agent), for example, Hydroxyl group and isocyanate group, amino group and isocyanate group, hydroxyl group and ester, amino group and ester, hydroxyl group and epoxy group, amino group and epoxy group, hydroxyl group and aziridine group, carboxylic acid and epoxy group, carboxylic acid and aziridine group, amino Group and aziridine group, hydroxyl group and halogen, hydroxyl group and mesylate group, hydroxyl group and triflate group, hydroxyl group and tosyloxy group, amino group and halogen, amino group and mesylate group, amino group and triflate group, amino group and tosyloxy group, etc. In each combination, which is the functional group on the structural unit side, which is a polymerizable functional group It may be a functional group of the side.

(3-2) End of main chain having polymerizable group Having a polymerizable group at the end of the main chain of the copolymer means that the main chain on any constituent unit located at the end of the main chain It shows that it has a structure in which a polymerizable group is introduced at the end of the chain.

  Specific examples of the terminal of the main chain having a polymerizable group include the following.

(In the general formula (IV), L ³ represents —S—CO—NH—, —S—CO—, —S—CH ₂ —CH (OH) —, —S—CH ₂ —CH (NH ₂ ) —, is a linking group represented by -S- ^{.R 25} _{is, - (CH 2) m -} , or _{- (C 2 H 4 O)} n -C 2 H 4 - represents a group represented by ^{.R 26} Represents a hydrogen atom or a methyl group, m is an integer of 0 to 20, and n is an integer of 1 to 8.)

  The structural unit located at the end of the main chain is not particularly limited as long as the effects of the side-chain liquid crystal polymer of the present disclosure are not impaired, and other structural units other than the structural units (A) to (C). It may be a unit.

  As a method for introducing a site having a polymerizable group at the end of the main chain, a monomer for deriving the structural units (A) and (B) described above is polymerized to synthesize the main chain of the copolymer, and then In addition, a method of introducing a polymerizable group by reacting a polymerizable group-introducing agent with a functional group generated at the end of the main chain may be mentioned.

(4) Other Structural Units The copolymer of the present disclosure includes, in addition to the structural units (A), (B), and (C), the structural units (A), (B), and (C). You may have the structural unit which does not correspond to any. By including other structural units in the copolymer, for example, solvent solubility, heat resistance, reactivity, and the like can be improved.
These other structural units may be one kind or two or more kinds.

  The content ratio of the other structural unit in the copolymer is preferably in the range of 0 mol% or more and 30 mol% or less when the amount of the structural unit contained in the copolymer is 100 mol%. More preferably, it is in the range of 0 mol% or more and 20 mol% or less. When the content ratio of the structural unit is large, the content ratios of the structural units (A) and (B) are relatively decreased, and it may be difficult to obtain the effect of the embodiment of the present disclosure.

(5) Copolymer In the embodiment of the present disclosure, the side chain type liquid crystal polymer may be a block copolymer having respective block portions of the structural units (A) and (B), and each of the structural units is not present. It may be a random copolymer arranged in a regular manner. However, in the present embodiment, a random copolymer is preferable from the viewpoint of uniformly exhibiting effects such as liquid crystal alignment and heat resistance throughout the copolymer.

  Further, the mass average molecular weight Mw of the side chain type liquid crystal polymer which is a copolymer is not particularly limited, but is preferably in the range of 5000 to 80000, more preferably in the range of 8000 to 50000, More preferably, it is in the range of not less than 10,000 and not more than 36000. By being in the said range, it is excellent in stability of a liquid crystal composition, and is excellent in the handleability at the time of retardation layer formation.

  The mass average molecular weight Mw is a value measured by GPC (gel permeation chromatography). For the measurement, HLC-8120GPC manufactured by Tosoh Corporation was used, the elution solvent was N-methylpyrrolidone to which 0.01 mol / liter of lithium bromide was added, and the polystyrene standard for calibration curve was Mw377400, 210500, 96000, 50400. , 206500, 10850, 5460, 2930, 1300, 580 (Easi PS-2 series manufactured by Polymer Laboratories) and Mw1090000 (manufactured by Tosoh Corporation), and TSK-GEL ALPHA-M × 2 (Tosoh Corporation) (Made by Co., Ltd.).

In this embodiment, the manufacturing method of a side chain type liquid crystal polymer is not specifically limited. For example, in the case of a copolymer having the structural units (A), (B), and (C), a monomer that derives the structural unit (A), a monomer that induces the structural unit (B), and a structural unit A monomer for deriving the precursor structural unit (C ′) of (C) is mixed at a desired ratio, and polymerized to a desired average molecular weight by a known polymerization means to form a main chain portion of the copolymer. Then, a compound having a polymerizable group such as an ethylenic double bond and a functional group that reacts with the functional group to form a bond with the functional group present in the side chain of the precursor structural unit (C ′) (polymerization) The polymerizable group may be introduced by reacting the polymerizable group introducing agent).
In addition, the monomer for deriving the structural unit (A), the monomer for deriving the structural unit (B), and the monomer deriving the precursor structural unit (C ′) of the structural unit (C) are each polymerized by known polymerization means. Then, the obtained polymers may be linked, and the monomer for deriving the structural unit (A), the monomer for deriving the structural unit (B), and the precursor structural unit (C ′) are derived. After any one or two of the monomers are polymerized by a known polymerization means, another monomer is added for further polymerization, and then the functional group present in the side chain of the precursor structural unit (C ′) The polymerizable group may be introduced by reacting a functional group that reacts with the functional group to form a bond and a compound having a polymerizable group such as an ethylenic double bond (polymerizable group introducing agent).

  As the polymerization means, a method generally used for polymerization of a compound having a vinyl group can be employed. For example, anionic polymerization or living radical polymerization can be used. In this embodiment, in particular, a method in which polymerization proceeds in a living manner, such as group transfer polymerization (GTP) disclosed in “J. Am. Chem. Soc.” 105, 5706 (1983), is used. Is preferred. According to this method, it is easy to make the molecular weight, molecular weight distribution, etc. within a desired range, so that the characteristics of the obtained side chain type liquid crystal polymer can be made uniform.

  Examples of the method of reacting the functional group of the precursor structural unit (C ′) with the functional group of the polymerizable group-introducing agent include the method described in paragraph 0076 of JP2011-145663A.

Further, when a copolymer having a polymerizable group at the end of the main chain is used, for example, after synthesizing the copolymer having the structural units (A) and (B) by living radical polymerization or the like, Polymerization is performed by reacting the functional group generated at the terminal with a functional group that reacts with the functional group to form a bond and a compound having a polymerizable group such as an ethylenic double bond (polymerizable group introducing agent). The method of introduce | transducing a sex group is mentioned.
For example, a structural unit (by reversible addition-fragmentation chain transfer) which is a kind of living radical polymerization using a RAFT (reversible addition-cleavage chain transfer) agent which is a kind of chain transfer agent having a thiocarbonylthio structure is used. When a copolymer having A) and (B) is synthesized, a thiol group is generated when the end of the main chain of the obtained copolymer is hydrolyzed, and thus reacts with the thiol group to form a bond. A copolymer having a polymerizable group at the end of the main chain can be obtained using a polymerizable group-introducing agent. RAFT polymerization has characteristics such that a polymer having a narrow molecular weight distribution can be synthesized while controlling the molecular weight, and one end of the polymer can be functionalized.
The chain transfer agent is one that pulls out radicals from the growth terminal of the radical polymerization reaction and stops the growth. The radical transferred to the chain transfer agent becomes a new polymerization reaction initiating species and is added to another radical polymerizable monomer to start growth of a new polymer. This process is called chain transfer of radical polymerization, and it is known that the reaction rate of the radical polymerizable monomer increases as the frequency of chain transfer increases.
The RAFT agent used in the present disclosure is not particularly limited, and examples thereof include benzyl benzodithioate and benzyl-1H-pyrrole-1-carbodithioate.
Examples of the polymerizable group-introducing agent to be reacted with the thiol group at the end of the main chain include compounds having a functional group that reacts with thiol such as an isocyanate group, an ester, an epoxy, an aziridine group, a halogen, or a tosyloxy group.

The said side chain type liquid crystal polymer may be used individually by 1 type, and may be used in combination of 2 or more type. In the present embodiment, the content of the side-chain liquid crystal polymer is 20 parts by mass with respect to 100 parts by mass of the solid content of the liquid crystal composition from the viewpoint that the effect of exhibiting liquid crystal orientation and excellent heat resistance can be obtained. It is preferably 80 parts by mass or less, more preferably 25 parts by mass or more and 70 parts by mass or less, and still more preferably 30 parts by mass or more and 60 parts by mass or less.
In the present disclosure, the solid content refers to all components except the solvent. For example, the polymerizable liquid crystal compound described later is included in the solid content even if it is liquid.

2. Polymerizable liquid crystal compound In the embodiment of the present disclosure, the polymerizable liquid crystal compound can be appropriately selected from conventionally known ones. In the present embodiment, it is preferably a polymerizable liquid crystal compound having a polymerizable group at at least one end of a rod-shaped mesogen because it is easily vertically aligned in combination with the side-chain liquid crystal polymer. A polymerizable liquid crystal compound having a polymerizable group at the terminal is more preferable.
The mesogen or rod-shaped mesogen included in the polymerizable liquid crystal compound can be the same as the mesogen or rod-shaped mesogen included in the liquid crystalline structural unit in the side-chain liquid crystal polymer.

  Examples of the polymerizable group possessed by the polymerizable liquid crystal compound include cyclic ether-containing groups such as oxirane rings and oxetane rings, and ethylenic double bond-containing groups. Among them, it exhibits photocurability and is excellent in handleability. From the viewpoint, an ethylenic double bond-containing group is preferable. Examples of the ethylenic double bond-containing group include a vinyl group, an allyl group, and a (meth) acryloyl group. Among them, a (meth) acryloyl group is preferable.

  In the present embodiment, the polymerizable liquid crystal compound exhibits a liquid crystal alignment property and is excellent in heat resistance, among others, the compound represented by the following general formula (V) and the following general formula (VI). One or more compounds selected from the above compounds are preferred.

(In general formula (V), R ³¹ represents a hydrogen atom or a methyl group, and R ³² represents a group represented by — (CH ₂ ) _p — or — (C ₂ H ₄ O) _{p ′} —. L ³ is a direct bond or a linking group represented by —O—, —O—C (═O) —, or —C (═O) —O—, and Ar ³ has a substituent. And an arylene group having 6 to 10 carbon atoms, and a plurality of L ³ and Ar ³ may be the same or different, and R ³³ represents —F, —Cl, —CN. , —OCF ₃ , —OCF ₂ H, —NCO, —NCS, —NO ₂ , —NHC (═O) —R ³⁴ , —C (═O) —OR ³⁴ , —OH, —SH, —CHO, — _{^{SO 3 H, -NR 34 2,}} -R 35, or ^{-OR 35, R 34} is a hydrogen atom or a carbon atom number of 1 to 6 alkyl groups R ³⁵ represents an alkyl group having 1 to 6 carbon atoms, b is an integer of 2 to 4 and p and p ′ are each independently an integer of 2 to 10).

(In General Formula (VI), R ⁴¹ and R ⁴² each independently represent a hydrogen atom or a methyl group, and R ⁴³ represents — (CH ₂ ) _q — or — (C ₂ H ₄ O) _{q ′} —. R ⁴⁴ represents a group represented by — (CH ₂ ) _r —, or — (OC ₂ H ₄ ) _{r ′} —, and L ⁴ represents a direct bond or —O—, In the linking group represented by —O—C (═O) — or —C (═O) —O—, Ar ⁴ is an arylene having 6 to 10 carbon atoms which may have a substituent. And a plurality of L ⁴ and Ar ⁴ may be the same or different, c is an integer of 2 or more and 4 or less, and q, q ′, r and r ′ are each independently 2 or more and 10 or less. Is an integer.)

In the general formula (V), p, p ′ and q, q ′, r, and r ′ in the general formula (VI) are each independently preferably 2 or more and 8 or less from the viewpoint of vertical alignment. Or less, more preferably 2 or more and 5 or less.
In the general formulas (V) and (VI), a site formed by connecting 2 or more and 4 or less of -L ³ -Ar ³ -and -L ⁴ -Ar ^4- is a mesogen.

  As the mesogen structure contained in the polymerizable liquid crystal compound, partial structures represented by the following chemical formulas (VII-1) to (VII-4) are preferably used, and among them, the following chemical formula (VII) including three or more ring structures is used. -1), a partial structure represented by at least one selected from the group consisting of (VII-2) and (VII-4) is preferably used. The hydrogen atom in the phenylene group or naphthylene group in the partial structure represented by the following chemical formulas (VII-1) to (VII-4) may be substituted with an alkyl group having 1 to 3 carbon atoms or a halogen atom. .

  Preferable specific examples of the compound represented by the general formula (V) and the compound represented by the general formula (VI) include those represented by the following chemical formulas (1) to (17). It is not limited.

In the present embodiment, the polymerizable liquid crystal compound can be used alone or in combination of two or more.
In the present embodiment, the content ratio of the polymerizable liquid crystal compound is 20 parts by mass or more and 80 parts by mass with respect to 100 parts by mass of the solid content of the liquid crystal composition from the viewpoint of obtaining the effect of exhibiting vertical alignment and excellent heat resistance. The mass is preferably 30 parts by mass or less, more preferably 30 parts by mass or more and 75 parts by mass or less, and still more preferably 40 parts by mass or more and 70 parts by mass or less.

3. Photopolymerization initiator In this embodiment, the photopolymerization initiator can be appropriately selected from conventionally known ones. Specific examples of such photopolymerization initiators include, for example, aromatic ketones containing thioxanthone, α-aminoalkylphenones, α-hydroxyketones, acylphosphine oxides, oxime esters, aromatic oniums. Preferred examples include salts, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds. Among them, at least one selected from the group consisting of acylphosphine oxide polymerization initiators, α-aminoalkylphenone polymerization initiators, α-hydroxyketone polymerization initiators, and oxime ester polymerization initiators is preferable.

  Examples of the acyl phosphine oxide polymerization initiator include bis (2,4,6-trimethylbenzoyl) -phenyl-phosphine oxide (for example, trade name: Irgacure 819, manufactured by BASF), bis (2,6-dimethoxy). Benzoyl) -2,4,4-trimethyl-pentylphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (trade name: Lucirin TPO: manufactured by BASF, etc.) and the like.

  Examples of the α-aminoalkylphenone polymerization initiator include 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one (for example, Irgacure 907, manufactured by BASF), 2- Benzyl-2- (dimethylamino) -1- (4-morpholinophenyl) -1-butanone (eg Irgacure 369, manufactured by BASF), 2- (dimethylamino) -2-[(4-methylphenyl) methyl] Examples include -1- [4- (4-morpholinyl) phenyl] -1-butanone (Irgacure 379EG, manufactured by BASF).

  Examples of the α-hydroxyketone polymerization initiator include 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane. -1-one (for example, trade name: Irgacure 127, manufactured by BASF), 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (for example, trade name: Irgacure 2959, manufactured by BASF), 1-hydroxy-cyclohexyl-phenyl-ketone (for example, trade name: Irgacure 184, manufactured by BASF, etc.), oligo {2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone} ( For example, trade name: ESACURE ONE, Lamberti, etc.).

  As the oxime ester polymerization initiator, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] (trade name: Irgacure OXE-01, manufactured by BASF), Ethanone, 1- [9-Ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (o-acetyloxime) (trade name: Irgacure OXE-02, manufactured by BASF), Methanone, Ethanone , 1- [9-Ethyl-6- (1,3-dioxolane, 4- (2-methoxyphenoxy) -9H-carbazol-3-yl]-, 1- (o-acetyloxime) (trade name ADEKA OPT- N-1919, manufactured by ADEKA).

In this embodiment, a photoinitiator can be used individually by 1 type or in combination of 2 or more types.
In this embodiment, the content ratio of the photopolymerization initiator is 0.1 parts by mass with respect to 100 parts by mass of the solid content of the liquid crystal composition from the viewpoint of promoting the curing of the side chain type liquid crystalline polymer and the polymerizable liquid crystal compound. It is preferably 10 parts by mass or less, more preferably 1 part by mass or more and 8 parts by mass or less.

4). Other Components The liquid crystal composition of the present embodiment may further contain other components as long as the effect is not impaired. Specifically, as other components, a leveling agent, a polymerization inhibitor, an antioxidant, a light stabilizer, and a solvent from the viewpoint of coating properties may be contained. These may be appropriately selected from conventionally known materials.
As the leveling agent, it is preferable to use a fluorine-based or silicone-based leveling agent. Specific examples of the leveling agent include, for example, the Megafac series manufactured by DIC Corporation described in JP2010-122325A, the TSF series manufactured by Momentive Performance Materials Japan, and Neos Corporation. Examples include the footage series. When using a leveling agent in this embodiment, it is preferable that the content rate shall be 0.001 mass part or more and 5 mass parts or less with respect to 100 mass parts of solid content of a liquid-crystal composition.

  The liquid crystal composition of the present embodiment may contain a solvent as necessary from the viewpoint of coatability. The solvent may be appropriately selected from conventionally known solvents that can dissolve or disperse each component contained in the liquid crystal composition. Specifically, for example, hydrocarbon solvents such as hexane and cyclohexane, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ether solvents such as tetrahydrofuran and propylene glycol monoethyl ether (PGME), chloroform, dichloromethane and the like Alkyl halide solvents, ester solvents such as ethyl acetate, propylene glycol monomethyl ether acetate, amide solvents such as N, N-dimethylformamide, and sulfoxide solvents such as dimethyl sulfoxide, methanol, ethanol, propanol, etc. Examples include alcohol solvents. In the present embodiment, the solvents can be used alone or in combination of two or more as a mixed solvent.

  The liquid crystal composition of the present embodiment is suitable for the production of a liquid crystal alignment film, and the side chain type liquid crystal polymer is easily vertically aligned, and accordingly, the polymerizable liquid crystal compound is easily vertically aligned. Suitable for the production of layers.

B. Retardation Film The retardation film of the present disclosure is a retardation film having a retardation layer, wherein the retardation layer contains a side chain type liquid crystal polymer and a polymerizable liquid crystal compound, and the side chain type liquid crystal. The polymer has a main chain including a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity, and any of the main chains It is made of a cured product of a liquid crystal composition containing a copolymer having a polymerizable group at at least one position selected from the group consisting of the side chain of the constituent unit and the end of the main chain.
In the retardation film of the present embodiment, since the retardation layer is formed of a cured product of the liquid crystal composition, as described above, the side chain liquid crystal polymer and the liquid crystalline polymer compound are combined to form a polymer. As the network develops, it exhibits high heat resistance.
Hereinafter, the structure of such a retardation film will be described. However, since the side-chain liquid crystal polymer and the polymerizable liquid crystal compound contained in the liquid crystal composition are as described above, description thereof is omitted here. .

The layer structure of the retardation film will be described with reference to the drawings. 1 to 3 each show an embodiment of a retardation film of the present disclosure. One embodiment of the retardation film 10 shown in the example of FIG. 1 is a retardation film in which an alignment film 3 and a retardation layer 1 are laminated on a substrate 2 in this order. One embodiment of the retardation film 10 shown in the example of FIG. 2 is a retardation film composed of only the retardation layer 1. In one embodiment of the retardation film 10 shown in the example of FIG. 3, the retardation layer 1 is directly formed on the substrate 2 ′. The retardation film shown in the example of FIG. 3 may be provided with a means for expressing the orientation regulating force on the surface of the substrate 2 ′ on the retardation layer 1 side.
In addition, as described above, the liquid crystal composition containing the above-described side chain type liquid crystal polymer and the polymerizable liquid crystal compound is such that the side chain type liquid crystal polymer is easily vertically aligned. Can easily be vertically aligned, and therefore can exhibit vertical alignment without using an alignment film.

1. Retardation layer Retardation layer 1 of an embodiment of this indication consists of a hardened material of a liquid crystal composition containing a side chain type liquid crystal polymer and a polymerizable liquid crystal compound.
Here, the side-chain type liquid crystal polymer and the polymerizable liquid crystal compound may be the same as those described in the liquid crystal composition of the embodiment of the present disclosure, and thus the description thereof is omitted here.

  The retardation layer is hardened in a state in which the liquid crystalline structural unit (B) having a side chain including a portion exhibiting liquid crystallinity possessed by the side chain liquid crystal polymer and the polymerizable liquid crystal compound are vertically aligned. Preferably there is. The cured product of the liquid crystal composition according to the embodiment of the present disclosure includes a structure in which the polymerizable group of the side chain type liquid crystal polymer and at least a part of the polymerizable group of the polymerizable liquid crystal compound are polymerized. As described above, since the structure in which at least a part of the polymerizable group of the side chain type liquid crystalline polymer is polymerized as well as the polymerizable group of the polymerizable liquid crystal compound is included, the retardation layer of the present embodiment is durable. The retardation layer has improved properties and heat resistance.

In addition, the liquid crystalline structural unit contained in the retardation layer includes nuclear magnetic resonance (NMR), infrared spectroscopy (IR), gas chromatogram mass spectrometry (GC-MS), X-ray photoelectron spectroscopy (XPS), It can be confirmed by using one or more methods from known analysis methods that can obtain molecular structure information such as time-of-flight secondary ion mass spectrometry (TOF-SIMS).
Moreover, it can be confirmed that the polymerizable liquid crystal compound is vertically aligned by measuring the phase difference with an automatic birefringence measuring apparatus (for example, trade name: KOBRA-WR, manufactured by Oji Scientific Instruments). .

The retardation layer has an in-plane main refractive index of nx, ny, a refractive index in the thickness direction of nz, and nx> ny, when the film thickness is about 1 μm or more and 10 μm or less. For example, it is preferable that (nx−ny) = 0 or more and about 0.0005 or less and (nx−nz) = − 0.1200 or more and −0.1030 or less. Further, it is preferable that nx is about 1.5314 to 1.5354, ny is about 1.5314 to 1.5354, and nz is about 1.6391 to 1.6472.
The phase difference can be measured by an automatic birefringence measuring apparatus (for example, trade name: KOBRA-WR, manufactured by Oji Scientific Instruments). Anisotropy that increases the phase difference of the phase difference layer can be confirmed from the chart of the optical phase difference and the angle of incidence of the measurement light when the measurement light is incident on the surface of the phase difference layer perpendicularly or obliquely.

  Further, the retardation layer includes a structure in which at least a part of the polymerizable group of the side-chain liquid crystal polymer included in the liquid crystal composition of the embodiment of the present disclosure and the polymerizable group of the polymerizable liquid crystal compound is polymerized. This can be confirmed by collecting and analyzing the material from the retardation layer. As an analysis method, NMR, IR, GC-MS, XPS, TOF-SIMS, and a combination thereof can be applied.

  The retardation layer may contain other components such as a photopolymerization initiator, a leveling agent, a polymerization inhibitor, an antioxidant, and a light stabilizer. In some cases, components such as a photopolymerization initiator that may be decomposed when irradiated with light to react with a polymerizable group are not included in the retardation layer.

  What is necessary is just to set the thickness of a phase difference layer suitably according to a use. Especially, it is preferable that they are 0.1 micrometer or more and 5 micrometers or less, and it is more preferable that they are 0.5 micrometer or more and 3 micrometers or less.

2. Alignment film In this specification, an alignment film refers to a layer for aligning liquid crystal components contained in a retardation layer in a certain direction.
As the alignment film used in the embodiment of the present disclosure, it is preferable to use a vertical alignment film because the liquid crystal composition of the embodiment of the present disclosure is easily aligned vertically.
The vertical alignment film is an alignment film having a function of vertically aligning the major axis of the mesogen of the liquid crystalline component contained in the retardation layer by being provided as a coating film.

The vertical alignment film is an alignment film having an alignment regulating force in the vertical direction, and various vertical alignment films used for the production of the C plate and various vertical alignment films applied to VA liquid crystal display devices can be applied. For example, a polyimide alignment film, an alignment film made of an LB film, or the like can be applied. Specifically, as the constituent material of the alignment film, for example, lecithin, silane-based surfactant, titanate-based surfactant, pyridinium salt-based polymer surfactant, silane coupling-based vertical such as n-octadecyltriethoxysilane Composition for alignment film, composition for polyimide vertical alignment film such as soluble polyimide having long chain alkyl group or alicyclic structure in side chain and polyamic acid having long chain alkyl group or alicyclic structure in side chain Can be applied.
In addition, as a composition for vertical alignment films, a composition for a polyimide-based vertical alignment film “JALS-2021” and “JALS-204” manufactured by JSR Co., Ltd., and “RN-1517” manufactured by Nissan Chemical Industries, Ltd. Commercial products such as “SE-1211”, “EXPOA-018”, “Fine Cure PXV-18” manufactured by Sanyo Chemical Industries, Ltd. can be applied. Further, a vertical alignment film described in JP-A-2015-191143 may be used.

  Although the formation method of an alignment film is not specifically limited, For example, it can be set as an alignment film by apply | coating the composition for alignment films mentioned later on the base material mentioned later, and providing an alignment control force. The means for imparting the alignment regulating force to the alignment film can be a conventionally known one.

  The thickness of the alignment film may be set as appropriate as long as the liquid crystalline components in the retardation layer can be aligned in a certain direction. The thickness of the alignment film is usually in the range of 1 nm to 10 μm, and preferably in the range of 60 nm to 5 μm.

3. Base Material In this embodiment, examples of the base material include a glass base material, a metal foil, and a resin base material. Especially, it is preferable that a base material has transparency, and it can select suitably from a conventionally well-known transparent base material. As a transparent substrate, in addition to a glass substrate, acetyl cellulose resins such as triacetyl cellulose, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyester resins such as polylactic acid, polypropylene, polyethylene, polymethylpentene, etc. It is formed using resins such as olefin resin, acrylic resin, polyurethane resin, polyether sulfone, polycarbonate, polysulfone, polyether, polyether ketone, acrylonitrile, methacrylonitrile, cycloolefin polymer, cycloolefin copolymer. Transparent resin base materials.

  The transparent substrate preferably has a transmittance in the visible light region of 80% or more, and more preferably 90% or more. Here, the transmittance | permeability of a transparent base material can be measured by JISK7361-1 (the test method of the total light transmittance of a plastic-transparent material).

Moreover, when forming a phase difference layer by a roll-to-roll system, it is preferable that a transparent base material is a flexible material which has the flexibility which can be wound up in roll shape.
Such flexible materials include cellulose derivatives, norbornene polymers, cycloolefin polymers, polymethyl methacrylate, polyvinyl alcohol, polyimide, polyarylate, polyethylene terephthalate, polysulfone, polyethersulfone, amorphous polyolefin, modified acrylic polymer, polystyrene. And epoxy resins, polycarbonates, polyesters, and the like. Among these, it is preferable to use a cellulose derivative or polyethylene terephthalate in the present embodiment. This is because the cellulose derivative is particularly excellent in optical isotropy, and therefore can be excellent in optical characteristics. Polyethylene terephthalate is preferable because it has high transparency and excellent mechanical properties.

The thickness of the substrate used in the present embodiment is not particularly limited as long as it is within the range that can provide the necessary self-supporting property, depending on the use of the retardation film, etc., but usually within the range of about 10 μm or more and 200 μm or less. It is.
In particular, the thickness of the substrate is preferably in the range of 25 μm to 125 μm, and more preferably in the range of 30 μm to 100 μm. When the thickness is thicker than the above range, for example, after forming a long retardation film and cutting it into a single-phase retardation film, the processing waste increases or the cutting blade wears out. This is because there is a case that becomes faster.

The configuration of the substrate used in the present embodiment is not limited to a configuration consisting of a single layer, and may have a configuration in which a plurality of layers are laminated. When it has the structure by which the several layer was laminated | stacked, the layer of the same composition may be laminated | stacked, and the several layer which has a different composition may be laminated | stacked.
For example, when the alignment film used in the present embodiment contains an ultraviolet curable resin, a primer layer for improving the adhesion between the transparent substrate and the ultraviolet curable resin is formed on the substrate. May be. This primer layer has only adhesiveness to both the base material and the ultraviolet curable resin, is visible optically transparent, and can pass ultraviolet light. For example, a vinyl chloride / vinyl acetate copolymer system Urethane-based ones can be appropriately selected and used.

Further, when the vertical alignment film is not provided, an anchor coat layer may be laminated on the substrate. The anchor coat layer can improve the strength of the substrate and ensure good vertical alignment. As the anchor coat material, a metal alkoxide, particularly a metal silicon alkoxide sol can be used. Metal alkoxides are usually used as alcoholic solutions. Since the anchor coat layer requires a uniform and flexible film, the thickness of the anchor coat layer is preferably about 0.04 μm to 2 μm, and more preferably about 0.05 μm to 0.2 μm.
When the substrate has an anchor coat layer, a binder layer is further laminated between the substrate and the anchor coat layer, or the anchor coat layer contains a material that enhances adhesion to the substrate. The adhesion between the material and the anchor coat layer may be improved. As the binder material used for forming the binder layer, a material that can improve the adhesion between the base material and the anchor coat layer can be used without particular limitation. Examples of the binder material include a silane coupling agent, a titanium coupling agent, and a zirconium coupling agent.

4). Method for producing retardation film A method for producing a retardation film according to an embodiment of the present disclosure is as follows.
Forming a liquid crystal composition according to an embodiment of the present disclosure;
A step of aligning the liquid crystalline constituent unit of the side chain type liquid crystal polymer in the liquid crystal composition formed into a film, and the polymerizable liquid crystal compound;
It has the process of forming a phase difference layer by having the process of superposing | polymerizing the said side chain type liquid crystal polymer and the said polymeric liquid crystal compound after the process of aligning.
As the liquid crystal composition, the same liquid crystal composition as that described in “A. Liquid crystal composition” can be used, and the description thereof is omitted here.

(1) Film forming step of liquid crystal composition A liquid crystal composition is uniformly coated on a support to form a film.
The support here may be on the base material, or may be on the orientation film of the base material provided with the orientation film.

  The coating method may be any method that can form a film with a desired thickness with high accuracy, and may be selected as appropriate. For example, gravure coating method, reverse coating method, knife coating method, dip coating method, spray coating method, air knife coating method, spin coating method, roll coating method, printing method, dip pulling method, curtain coating method, die coating method, casting Method, bar coating method, extrusion coating method, E-type coating method and the like.

(2) Step of orienting liquid crystal component Next, the liquid crystal constituent unit of the side chain type liquid crystal polymer in the liquid crystal composition formed and the temperature at which the polymerizable liquid crystal compound can be vertically aligned are adjusted and heated. . By the heat treatment, the liquid crystalline structural unit of the side chain type liquid crystal polymer and the polymerizable liquid crystal compound can be vertically aligned and dried, and can be fixed while maintaining the alignment state.
Since the temperature at which vertical alignment is possible differs depending on each substance in the liquid crystal composition, it is necessary to appropriately adjust the temperature. For example, it is preferably performed within a range of 40 ° C. or higher and 200 ° C. or lower, and more preferably performed within a range of 40 ° C. or higher and 100 ° C. or lower.
As the heating means, known heating and drying means can be appropriately selected and used.
In addition, the heating time may be selected as appropriate, and is selected, for example, within a range of 10 seconds to 2 hours, preferably 20 seconds to 30 minutes.

(3) Step of polymerizing side chain type liquid crystal polymer and polymerizable liquid crystal compound In the alignment step, the coating film fixed in a state where the alignment state of the liquid crystalline component is maintained is irradiated with light, for example, to form side chains. A liquid crystal polymer and a polymerizable liquid crystal compound can be polymerized, and a retardation layer made of a cured product of the liquid crystal composition can be obtained.
As the light irradiation, ultraviolet irradiation is preferably used. For the ultraviolet irradiation, ultraviolet rays emitted from light rays such as ultra-high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halide lamp can be used. Irradiation of energy beam source may if appropriately selected, accumulative exposure at an ultraviolet wavelength of 365 nm, is preferably in the range of, for example, 10 mJ / cm ² or more 10000 mJ / cm ² or less.

5. Applications The retardation film of the present disclosure is suitably used as a retardation film having a positive C-type retardation layer. The retardation film of the present disclosure is suitably used, for example, as a viewing angle compensation film, and is suitably used for optical members for various display devices as described later.

C. A laminate for transfer, comprising a retardation layer and a support that releasably supports the retardation layer,
The retardation layer contains a side-chain liquid crystal polymer and a polymerizable liquid crystal compound, and the side-chain liquid crystal polymer has a non-liquid crystalline and non-polymerizable structural unit (A) and a portion exhibiting liquid crystallinity. A main chain containing a liquid crystalline structural unit (B) having a side chain containing, and at least one position selected from the group consisting of a side chain of one of the structural units in the main chain and an end of the main chain Comprising a cured product of a liquid crystal composition comprising a copolymer having a polymerizable group,
It is the transfer laminated body used for transfer of a phase difference layer.

In the transfer laminate of the present embodiment, since the retardation layer is made of a cured product of the liquid crystal composition, it exhibits vertical alignment and has improved durability and heat resistance. According to the transfer laminate of the present embodiment, for example, the retardation layer of the present disclosure, which is a thin film not including a substrate, can be transferred to any other optical member or the like.
According to the transfer laminate of the present embodiment, for example, the retardation film 10 composed only of the retardation layer 1 shown in the example of FIG. 2 or the base material is not included as shown in the example of FIG. A retardation film comprising the laminate 26 in which the film 23 and the retardation layer 21 are laminated can be provided. That is, as long as the retardation layer can be peeled at least, an alignment film or the like may be laminated on the retardation layer used for transfer of the transfer laminate.
Hereinafter, the configuration of such a transfer laminate will be described, but the description of the liquid crystal composition of the embodiment of the present disclosure is omitted here because it is as described above.

The layer structure of the transfer laminate will be described with reference to the drawings. 4 and 5 each show an embodiment of the transfer laminate of the present disclosure.
One embodiment of the transfer laminate 20 shown in the example of FIG. 4 is a transfer laminate in which an alignment film 13 and a retardation layer 11 are laminated in this order on a second substrate 12. And the phase difference layer 16 provided for the above, and a support 15 that releasably supports the phase difference layer, and 15 having an alignment film 13 provided on the second substrate 12. In the transfer laminate shown in the example of FIG. 4, the peel strength between the second substrate 12 and the alignment film 13 is greater than the peel strength between the alignment film 13 and the retardation layer 11. This is an example of a transfer laminate that is peeled off at the interface 17 between the alignment film and the retardation layer and can transfer the retardation layer 11 (16).
One embodiment of the transfer laminate 30 shown in the example of FIG. 5 is a transfer laminate in which an alignment film 23 and a retardation layer 21 are laminated in this order on a second base material 22. The retardation layer to be provided includes a retardation layer 26 to be used for transfer composed of the retardation layer 21 and the alignment film 23, and a support 25 that detachably supports the retardation layer. In the transfer laminate shown in the example of FIG. 5, the peel strength between the second base material 22 and the alignment film 23 is smaller than the peel strength between the alignment film 23 and the retardation layer 21. The retardation layer 26 peeled off at the interface 27 between the second substrate 22 and the alignment film 23 and used for transfer is an example of a transfer laminate that can transfer the retardation layer 21 and the alignment film 23. is there.

  For example, whether the peel strength between the second base material and the alignment film is larger or smaller than the peel strength between the alignment film and the retardation layer is determined by the separation of the retardation layer and at which interface Can be confirmed. It can be analyzed, for example, by IR or the like at which interface.

  In addition, in the embodiment of the transfer laminate 40 shown in the example of FIG. 6, the second substrate 32 is used as a retardation layer 36 to be transferred and a support 35 that releasably supports the retardation layer. And a phase difference layer 31 is laminated on the second base material 32 in this order.

Hereinafter, although this embodiment is described, the retardation layer can be the same as the retardation layer described in “B. Retardation film”, and thus the description thereof is omitted here.
In addition, the alignment film and the base material may be the same as the alignment film and the base material described in “B. Retardation film”, and examples of the method for adjusting the peel strength include the following methods. be able to.

In order to obtain the transfer laminate 20 shown in the example of FIG. 4, the peel strength between the second substrate 12 and the alignment film 13 is made larger than the peel strength between the alignment film 13 and the retardation layer 11. For example, a method in which the solvent contained in the composition for forming an alignment film can dissolve the second substrate can be used. As the second substrate, a resin substrate is preferably used, and surface treatment for improving the adhesiveness may be performed on the substrate surface. In such a case, the adhesion between the resin base material and the alignment film can be improved.
In addition, in order to reduce the peel strength between the alignment film and the retardation layer so that the peel strength between the substrate and the alignment film is greater than the peel strength between the alignment film and the retardation layer, the solvent resistance of the alignment film It is also preferable to make the value relatively high. When the solvent resistance of the alignment film is relatively high, when forming the retardation layer by applying the liquid crystal composition on the alignment film, the alignment film is difficult to dissolve in the solvent in the liquid crystal composition. The adhesion between the alignment film and the retardation layer can be lowered.

On the other hand, in order to obtain the transfer laminate 30 shown in the example of FIG. In order to do this, for example, a release treatment may be applied to the surface of the substrate, or a release layer may be formed. Thereby, the peelability of a base material can be improved and the peel strength of a base material and an orientation layer can be made smaller than the peel strength of an orientation layer and a phase difference layer.
Examples of the mold release treatment include surface treatment such as fluorine treatment and silicone treatment. Examples of the material for the release layer include a fluorine release agent, a silicone release agent, and a wax release agent. Examples of the method for forming the release layer include a method in which a release agent is applied by a coating method such as dip coating, spray coating, or roll coating.
Further, in order to obtain the transfer laminate 40 shown in the example of FIG. 6, if necessary, the surface of the base material may be subjected to a release treatment or a release layer is formed. Also good.

Although the base material used for the transfer laminate may or may not have flexibility, it is preferable to have flexibility because the base material is easily peeled off.
The thickness of the base material used for the transfer laminate is usually the above-mentioned due to the balance between sufficient self-supporting strength and flexibility sufficient to adapt to the transfer laminate production and transfer process of this embodiment. In the case of a sheet of material, it is preferably in the range of 20 μm to 200 μm.

  The retardation layer transferred from the transfer laminate of the present disclosure is suitably used for the same application as the retardation film, and the positive C-type retardation layer can be transferred to optical members for various display devices. And can be suitably used to provide a thin film optical member.

D. Optical member The optical member of this indication equips the retardation film of this indication with a polarizing plate.

The optical member of this embodiment will be described with reference to the drawings. FIG. 7 is a schematic cross-sectional view showing one embodiment of the optical member.
In the example of the optical member 60 in FIG. 7, the polarizing plate 50 is disposed on the retardation film 10 of the present disclosure. Between the retardation film 10 and the polarizing plate 50, you may have the adhesion layer (adhesion layer) as needed (not shown).

In the present embodiment, the polarizing plate has a plate shape that allows only light oscillating in a specific direction to pass therethrough, and can be appropriately selected from conventionally known polarizing plates. For example, a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer saponified film, which is dyed with iodine or a dye and stretched can be used.
In the present embodiment, the pressure-sensitive adhesive or adhesive for the pressure-sensitive adhesive layer (adhesive layer) may be appropriately selected from conventionally known pressure-sensitive adhesives (pressure-sensitive adhesives), two-component curable adhesives, Any adhesive form such as an ultraviolet curable adhesive, a thermosetting adhesive, and a hot melt adhesive can be suitably used.

  In addition to the polarizing plate, the optical member of the present embodiment may further include other layers included in the known optical member. Examples of the other layers include an antireflection layer, a diffusion layer, an antiglare layer, an antistatic layer, and a protective film, in addition to other retardation layers different from the retardation layer of the present embodiment. However, it is not limited to these.

  The optical member of this embodiment can be used as an optical member that suppresses reflection of external light, for example. The optical member of the present disclosure in which the retardation film of the present disclosure and a circularly polarizing plate are laminated is suitably used, for example, as an optical member for suppressing external light reflection for a light-emitting display device. It can be suitably used as a wide viewing angle polarizing plate for display devices.

E. Display Device A display device according to the present disclosure includes the retardation film of the present embodiment or the optical member of the present embodiment.
Examples of the display device include a light emitting display device and a liquid crystal display device, but are not limited thereto.

  Among them, in order to include the retardation film of the present embodiment or the optical member of the present embodiment, in particular, in a light emitting display device such as an organic light emitting display device having a transparent electrode layer, a light emitting layer, and an electrode layer in this order. This has the effect of improving the viewing angle while suppressing external light reflection.

An example of a display device according to the present disclosure will be described with reference to the drawings. FIG. 8 is a schematic cross-sectional view illustrating a light-emitting display device according to an embodiment of the present disclosure.
In the example of the light emitting display device 100 of FIG. 8, the polarizing plate 50 is disposed on the light exit surface side of the retardation film 10, and the transparent electrode layer 71, the light emitting layer 72, and the electrode layer 73 are disposed on the opposite surface. And in this order.
Examples of the light emitting layer 72 include a structure in which a hole injection layer, a hole transport layer, a light emitting layer, and an electron injection layer are stacked in this order from the transparent electrode layer 71 side. In the present embodiment, the transparent electrode layer, the hole injection layer, the hole transport layer, the light emitting layer, the electron injection layer, the electrode layer, and other configurations can be appropriately selected from known ones. The light-emitting display device thus manufactured can be applied to, for example, a passive drive type organic EL display and an active drive type organic EL display.
Note that the display device of the present embodiment is not limited to the above-described configuration, and may be a known configuration appropriately selected.

  Hereinafter, the embodiment of the present disclosure will be specifically described with reference to examples. The embodiments of the present disclosure are not limited by these descriptions.

<Measurement method of mass average molecular weight (Mw)>
The mass average molecular weight measurement was performed using HLC-8120GPC manufactured by Tosoh Corporation, the elution solvent was N-methylpyrrolidone to which 0.01 mol / liter of lithium bromide was added, and the polystyrene standard for calibration curve was Mw377400, 210500, 96000, 50400, 206500, 10850, 5460, 2930, 1300, 580 (Easi PS-2 series manufactured by Polymer Laboratories) and Mw1090000 (manufactured by Tosoh Corporation), and the measurement column is TSK-GEL ALPHA-M × 2. The book was made by Tosoh Corporation.

(Synthesis Example 1: Synthesis of liquid crystal monomer b)
First, according to the following scheme 1, 4- [2- (acryloyloxy) ethyloxy] benzoic acid was synthesized.

  Next, according to the following scheme 2, a liquid crystal monomer b was obtained. Specifically, 4- [2- (acryloyloxy) ethyloxy] benzoic acid obtained above (179.4 g, 759.4 mmol), 4′-cyano-4-hydroxybiphenyl (148.3 g, 759.4 mmol) ), 35% hydrochloric acid solution (2.373 g), and N, N-dimethylaminopyridine (DMAP) (2.739 g, 22.78 mmol) in dichloromethane (1243 g) suspension in N, N-dicyclohexylcarbodiimide (DCC). ) (170.8 g, 827.8 mmol) in dichloromethane (170.8 g) was added dropwise. After completion of dropping, the mixture was stirred overnight, the precipitate was filtered, and the solvent was distilled off. Methanol (1421 g) was added to the resulting crude product, and the mixture was stirred for 1 hour at room temperature and purified by suspension. The precipitate was filtered, and the obtained crystals were dried to obtain 4′-cyano-4- {4- [2- (acryloyloxy) ethyloxy] benzoate} (the following chemical formula b) in a yield of 92.9%. (301.1 g, 728.3 mmol).

(Synthesis Example 2: Synthesis of side chain type liquid crystal polymer A-1)
A non-liquid crystalline and non-polymerizable monomer represented by the following chemical formula a, a polymerizable group-introducing precursor monomer represented by the following chemical formula c, and a polymerizable group introducing agent represented by the following chemical formula d were prepared (any Also made by Tokyo Chemical Industry Co., Ltd.).

Non-liquid crystalline and non-polymerizable monomer a (manufactured by Tokyo Chemical Industry) (6.22 g, 61.6 mmol), liquid crystal monomer b obtained in Synthesis Example 1 (50.9 g, 123 mmol), polymerizable group-introduced precursor monomer c Cyclohexanone (155.5 g) was added to (2.96 g, 20.5 mmol), and dissolved by stirring at 80 ° C. in a nitrogen atmosphere. A solution of azobisisobutyronitrile (AIBN) (825 mg, 5.03 mmol) dissolved in cyclohexanone (9.5 g) was added dropwise to the reaction solution over 30 minutes. Stir for hours. After completion of the reaction, the temperature was raised to 105 ° C. and stirred for 12 minutes to deactivate the initiator. Then, after cooling to room temperature, 10 degreeC methanol was dripped at another container which is stirring, and was stirred for 20 minutes. After removing the supernatant, the slurry was filtered, and the resulting crude product was again stirred in methanol at 10 ° C. for 20 minutes, and the supernatant was removed and filtered. The obtained crystals were dried to obtain a polymerizable group-introduced precursor polymer in a yield of 85%.
N, N-dimethylacetamide (DMAc) (35.8 g) was added to the obtained polymerizable group-introduced precursor polymer (5.00 g), and a calcium chloride tube was attached to the reaction vessel and stirred at 60 ° C. to dissolve. . Methylhydroquinone (40.0 mg), polymerizable group-introducing agent d (160 mg, 1.03 mmol) and dibutyltin dilaurate (40.0 μg) were added and stirred for 4.5 hours. As a result of IR analysis in the system, since the peak at 2260 cm ⁻¹ disappeared, it was judged that the reaction was completed. After completion of the reaction, the reaction mixture was cooled to room temperature, and then methanol (205 g) at room temperature was dropped into another stirring vessel and stirred for 20 minutes. After removing the supernatant, the resulting slurry was filtered, and the resulting crude product was again stirred in methanol (205 g) at 9 ° C. for 20 minutes, and the supernatant was removed and filtered. The obtained crystals were dried to obtain side chain liquid crystal polymer A-1 in a yield of 76% (3.91 g).

(Synthesis of side chain type liquid crystal polymers A-2 to A-7 and B)
In Synthesis Example 2, side chain liquid crystal polymers A-2 to A-8 and B were synthesized in the same manner as Synthesis Example 2 except that the composition of each component was changed as shown in Table 1.

(Synthesis of side chain type liquid crystal polymer A-8)
In Synthesis Example 2, the amount of each component added was monomer a (2.55 g, 25.3 mmol), monomer b (20.9 g, 50.6 mmol), polymerizable group-introduced precursor monomer c (1.22 g, 8. 43 mmol), side chain liquid crystal polymer A-8 was synthesized in the same manner as in Synthesis Example 2 except that AIBN (4.00 mg, 2.07 mmol) was changed.

[Example 1]
(Preparation of liquid crystal composition)
In 283 parts by weight of cyclohexanone and 283 parts by weight of methyl ethyl ketone, 30 parts by weight of the side chain type liquid crystal polymer A-1, 70 parts by weight of the polymerizable liquid crystal compound C, and a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, Irgacure) 907) was dissolved to prepare a liquid crystal composition of Example 1.

[Examples 2 to 8 and Comparative Example 1]
In Example 1, the liquid crystal compositions of Examples 2 to 8 and Comparative Example 1 were obtained in the same manner as Example 1 except that the side chain type liquid crystal polymer was changed as shown in Table 2.

[Evaluation]
Using a PET substrate having a thickness of 38 μm, a vertical alignment film composition (Fine Cure PXV-18 manufactured by Sanyo Chemical Industries, Ltd.) is coated on one side so as to have a film thickness of 3 μm, and polarized light of 20 mJ / cm ² . An alignment film was produced by irradiating ultraviolet rays.
Subsequently, the prepared liquid crystal composition is applied on the alignment film by a die head coating method, dried at a drying temperature of 85 ° C. for 60 seconds, and then irradiated with ultraviolet rays (UV) to form a retardation layer to obtain an optical film. It was.
Thereafter, the retardation layer was transferred to a glass with adhesive, and the retardation Rth (nm) in the thickness direction was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. The same measurement was performed again after heating for 1 hour. Here, when the phase difference Rth (nm) before heating is 100%, the ratio of the phase difference decreased after heating is shown in Table 2 as the variation rate (%) of the phase difference before and after heating.

In Examples 1 to 8 using the side chain type liquid crystal polymer having a polymerizable group, the variation rate of the retardation before and after heating was 8.2 to 11.9%. On the other hand, the variation in retardation after the heat test of Comparative Example 1 using the side chain type liquid crystal polymer having no polymerizable group was 15.8%.
From this, it was shown that the heat resistance of the produced optical film is improved by introducing a polymerizable group into the side chain type liquid crystal polymer.

DESCRIPTION OF SYMBOLS 1 Phase difference layer 2, 2 'Base material 3 Orientation film 10 Phase difference film 11, 21, 31 Phase difference layer 12, 22, 32 Second base material 13, 23 Orientation film 15, 25, 35 Peelable support body 16, 26, 36 Retardation layer 17 used for transfer Interface 27 between alignment film and retardation layer Interface 20, 30, 40 between second substrate and alignment film Transfer laminate 50 Polarizing plate 60 Optical member 71 Transparent Electrode layer 72 Light emitting layer 73 Electrode layer 100 Light emitting display device

Claims (13)

  A main chain having a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline structural unit (B) having a side chain containing a portion exhibiting liquid crystallinity, and any structure in the main chain A side chain type liquid crystal polymer comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of a side chain of a unit and a terminal of a main chain.   The side chain type liquid crystal polymer according to claim 1, wherein the copolymer includes a structural unit (C) having a side chain containing the polymerizable group.   The side chain type liquid crystal polymer according to claim 2, wherein the structural unit (C) contains the polymerizable group at the end of the side chain. The side-chain liquid crystal polymer according to claim 2 or 3, wherein the structural unit (C) includes a structural unit represented by the following general formula (III).
(In General Formula (III), R ²¹ represents a hydrogen atom or a methyl group, and R ²² represents — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —C ₂ H ₄ —. L ² represents a direct bond or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—. _{NH -, - COO-CH 2} -CH (OH) -, - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{OCO -, - O-CH 2} -CH (OH) -, - CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{O -, - NH-CH 2} -CH (OH) -, - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) - _{, -CH (NH 2) -CH 2} -NH -, - O -, - NH -, - S-CO-NH -, - NH-CO-S -, - S-CO -, - CO-S-, _{-S -, - S-CH 2} -CH (OH) -, - CH (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 R represents a linking group represented by —S—, —CH (OH) —, or —CH (NH ₂ ) —, and R ²³ represents — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O). _{n ′} —C ₂ H ₄ — represents a group, R ²⁴ represents a hydrogen atom or a methyl group, and m and m ′ are each independently an integer of 0 or more and 20 or less. Each is independently an integer of 1 to 8.)   A portion containing a side-chain liquid crystal polymer, a polymerizable liquid crystal compound, and a photopolymerization initiator, wherein the side-chain liquid crystal polymer has a non-liquid crystalline and non-polymerizable structural unit (A) and a liquid crystalline property. A main chain containing a liquid crystalline structural unit (B) having a side chain containing, and at least one position selected from the group consisting of a side chain of one of the structural units in the main chain and an end of the main chain A liquid crystal composition comprising a copolymer having a polymerizable group.   The liquid crystal composition according to claim 5, wherein the copolymer has a structural unit (C) having a side chain containing the polymerizable group.   The liquid crystal composition according to claim 6, wherein the structural unit (C) contains the polymerizable group at a terminal of a side chain. The liquid crystal composition according to claim 6 or 7, wherein the structural unit (C) includes a structural unit represented by the following general formula (III).
(In General Formula (III), R ²¹ represents a hydrogen atom or a methyl group, and R ²² represents — (CH ₂ ) _m —, or — (C ₂ H ₄ O) _n —C ₂ H ₄ —. L ² represents a direct bond or —OCO—NH—, —NH—COO—, —NH—CO—NH—, —OCO—, —COO—, —NH—CO—, —CO—. _{NH -, - COO-CH 2} -CH (OH) -, - CH (OH) -CH 2 -OCO -, - COO-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{OCO -, - O-CH 2} -CH (OH) -, - CH (OH) -CH 2 -O -, - O-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 - _{O -, - NH-CH 2} -CH (OH) -, - CH (OH) -CH 2 -NH -, - NH-CH 2 -CH (NH 2) - _{, -CH (NH 2) -CH 2} -NH -, - O -, - NH -, - S-CO-NH -, - NH-CO-S -, - S-CO -, - CO-S-, _{-S -, - S-CH 2} -CH (OH) -, - CH (OH) -CH 2 -S -, - S-CH 2 -CH (NH 2) -, - CH (NH 2) -CH 2 R represents a linking group represented by —S—, —CH (OH) —, or —CH (NH ₂ ) —, and R ²³ represents — (CH ₂ ) _{m ′} — or — (C ₂ H ₄ O). _{n ′} —C ₂ H ₄ — represents a group, R ²⁴ represents a hydrogen atom or a methyl group, and m and m ′ are each independently an integer of 0 or more and 20 or less. Each is independently an integer of 1 to 8.)   A retardation film having a retardation layer, wherein the retardation layer contains a side-chain liquid crystal polymer and a polymerizable liquid crystal compound, and the side-chain liquid crystal polymer is non-liquid crystalline and non-polymerizable. Having a main chain comprising the structural unit (A) and a liquid crystalline structural unit (B) having a side chain containing a liquid crystalline moiety, and the side chain and main chain of any structural unit in the main chain A retardation film comprising a cured product of a liquid crystal composition, comprising a copolymer having a polymerizable group at at least one position selected from the group consisting of terminals.   A step of forming a retardation layer by polymerizing a side chain type liquid crystal polymer and a polymerizable liquid crystal compound after forming the liquid crystal composition according to any one of claims 5 to 8 and aligning the liquid crystal. A method for producing a retardation film. A retardation layer and a support that releasably supports the retardation layer,
The retardation layer contains a side-chain liquid crystal polymer and a polymerizable liquid crystal compound, and the side-chain liquid crystal polymer has a non-liquid crystalline and non-polymerizable structural unit (A) and a portion exhibiting liquid crystallinity. A main chain containing a liquid crystalline structural unit (B) having a side chain containing, and at least one position selected from the group consisting of a side chain of one of the structural units in the main chain and an end of the main chain Comprising a cured product of a liquid crystal composition comprising a copolymer having a polymerizable group,
A laminate for transfer used for transferring a retardation layer.   An optical member comprising a polarizing plate in the retardation film according to claim 9.   A display device comprising the retardation film according to claim 9 or the optical member according to claim 12.