JP6369240B2 - Liquid crystal compound having pyrrole or thiophene skeleton, liquid crystal composition and polymer thereof - Google Patents

Description

  The present invention relates to a compound having a 5-membered ring structure such as 2,5-substituted pyrrole, 1,3-substituted isoindoles or 2,5-substituted thiophenes, a liquid crystal composition containing the compound, and the liquid crystal composition The present invention relates to a polymer obtained from the above, an optically anisotropic film, and uses thereof.

  In recent years, liquid crystal compounds having a polymerizable group have been used for optically anisotropic films exhibiting birefringence (optical anisotropy) such as reflective polarizing plates and retardation plates. This compound exhibits birefringence in a liquid crystal state, and its orientation is fixed by polymerization. Examples of the fixed alignment state of the polymer include homogeneous (horizontal alignment), tilt (tilt alignment), homeotropic (vertical alignment), and twist (twist alignment).

  An optically anisotropic film having homogeneous orientation can be used as, for example, a composite retardation plate or a circularly polarizing plate by combining with a half-wave plate, a quarter-wave plate, or a film having other optical functions. (See Patent Document 1).

An optically anisotropic film having homeotropic orientation has an optical axis direction in the _nz direction,
Since the refractive index in the optical axis direction is larger than the refractive index in the orthogonal direction, the refractive index ellipsoid is classified as a positive C-plate. This positive C-plate can be applied to optical compensation such as a horizontally aligned liquid crystal mode, so-called IPS (In-Plane Switching) mode, for example, improvement of viewing angle characteristics of a polarizing plate by combining with a film having other optical functions. (Non-patent documents 1 to 3, Patent documents 2 and 3).

  As for the compound used for the application of the optical anisotropic body, the optical characteristics necessary for the optically anisotropic film differ depending on the application and purpose, and various liquid crystal compounds have been developed. Moreover, since it is often difficult to control the anisotropy alone, it is used as a liquid crystal composition in combination with various compounds.

  Such a liquid crystal composition is dissolved in an organic solvent and used as an ink for the purpose of adjusting coating properties. In order to produce a film having optical anisotropy using a liquid crystal composition, an ink in which a liquid crystal compound, a photopolymerization initiator, a surfactant, etc. are dissolved in an organic solvent to adjust the solution viscosity, leveling property, etc. Prepare. This ink is applied to an alignment-treated substrate, the solvent is dried, and the liquid crystal composition is aligned on the substrate. Next, the polymer is irradiated with ultraviolet rays to fix the alignment state. Usually, after the solvent is removed by drying, the polymerization is carried out at room temperature until polymerization, and during this time, the liquid crystal state must be maintained without precipitation of crystals. Therefore, the polymerizable compound used for the liquid crystal composition must maintain good compatibility with other liquid crystal compounds and high liquid crystallinity near room temperature. Furthermore, in order to be used as an ink, high solubility in an organic solvent is also required.

  In addition to the properties of optical anisotropy, the polymer obtained from the liquid crystal composition has high transparency, high mechanical strength, high adhesion to the substrate, low shrinkage, high heat resistance, and high resistance. Properties such as chemical properties are also required.

In an optically anisotropic layer formed of rod-like molecules, usually two refractive indexes ne (abnormal refractive index in a direction parallel to the molecular long axis) and no (normal in a direction perpendicular to the molecular long axis) of the anisotropic molecule (Refractive index) decreases as the wavelength increases. At this time, since ne has a larger refractive index change rate with respect to the wavelength than no, the refractive index anisotropy (Δn = ne−no) becomes smaller as the applied wavelength becomes larger. On the other hand, in a display device such as a liquid crystal display (LCD), the light source is white light composed of light having a wavelength of about 380 to 800 nm. A normal optical anisotropic layer is used to form a 1 / 2λ or 1 / 4λ plate. When designing and applying, the above-described wavelength dispersion causes a problem that the polarization state changes depending on the wavelength, and the light becomes colored. In order to prevent this problem, it is necessary to control the wavelength dispersion so that the designed phase difference is achieved at each wavelength, a material having a low dependency of refractive index anisotropy by wavelength (low wavelength dispersion characteristic), and further There is a demand for a material whose refractive index anisotropy increases as the wavelength increases (reverse wavelength dispersion characteristic).

In order to obtain an optically anisotropic layer having reverse wavelength dispersion characteristics, a method of laminating two retardation layers with respective angles in the direction of refractive index anisotropy has been proposed (Patent Document 4). And 5). However, since such a laminate requires two retardation layers, there are problems in manufacturing complexity for forming the laminate and an increase in the thickness of the optically anisotropic layer. .
In recent years, there has been a demand for an optically anisotropic layer having reverse wavelength dispersion without being laminated in order to solve such problems, and liquid crystalline compounds having reverse wavelength dispersion characteristics have been proposed (Patent Documents 6 to 6). 10).

  However, since the compound described in Patent Document 6 has a low refractive index anisotropy, it is necessary to increase the film thickness in order to obtain a desired phase difference, and since the aspect ratio is small, it is difficult to control the alignment uniformity. Has a long synthetic route, so there are concerns about problems such as difficulty in manufacturing. Since the compounds described in Patent Documents 7 and 8 have absorption in the visible region, they tend to cause a decrease in transmittance and color unevenness, and are not suitable for use in optical applications. The compounds described in Patent Documents 9 and 10 are relatively good in terms of optical properties and manufacturing processes, but further improvement in properties is required in terms of mechanical strength to the polymer, adhesion to the substrate, heat resistance, and the like. Yes.

JP 2002-372623 A International Publication No. 05/38517 US Patent Application Publication No. 2006/182900 JP-A-10-68816 JP 2001-4837 A Special table 2010-522893 JP 2009-179563 A International Publication No. 2012/169424 JP 2005-289980 A JP 2010-31223 A

M.S.Park et al, IDW '04 FMC8-4 M.Nakata et al, SID '06 P-58 K.J.Kim et al, SID '06 Digest p.1158-1161

  An object of the present invention is to provide a liquid crystal material that can provide an optically anisotropic layer that exhibits reverse wavelength dispersion or low wavelength dispersion in a single layer and has excellent surface hardness.

As a result of intensive studies, the inventors have found that a liquid crystalline compound having a 5-membered ring structure such as 2,5-substituted pyrrole, 1,3-substituted isoindoles or 2,5-substituted thiophenes has the above-mentioned problems. We have found that the problem can be solved and have completed the invention. That is, the present invention is as follows.

[1]
A compound represented by the following formula (I).

(In the formula (I),
A ¹ and A ² are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone -2,7-diyl, carbazole-3,6-diyl, anthracene-2
6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl, in which at least one hydrogen is fluorine , Chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons, or 1 to 1 carbons May be replaced by 5 alkanoyl;
Z ¹ and Z ² are each independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, at least one —CH ₂ — is —O—, —CO—, —COO—, —
May be replaced by OCO-, -CH = CH-, -CF = CF-, or -C≡C-, in which hydrogen may be replaced by halogen;
n and m are each independently an integer of 0 to 3, and 1 ≦ m + n ≦ 4;
X ¹ is —NR ³ — or —S—, R ³ is hydrogen or a monovalent organic group;
Each X ² is independently —O—, —S—, or —NR ⁴ —, and R ⁴ is hydrogen or methyl;
E is hydrogen, or two E's are bonded to each other to form an aromatic ring having 14 or less carbon atoms,
R ¹ and R ² are each independently hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, or 1 to 20 carbons. Alkoxy, an alkyl ester having 1 to 20 carbon atoms, or a group represented by the formula (4);

式（４）中、Ｙ^１は単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、または−ＯＣＯＯ−であり；Ｙ^２は単結合または炭素数１〜２０のアルキレンであり、該アルキレンにおいて少なくとも一つの−ＣＨ_２−は−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＨ＝ＣＨ−、または−Ｃ≡Ｃ−で置き換えられてもよく；ＰＧは、式（ＰＧ−１）〜（ＰＧ−８）のいずれか１つで表される重合性の基であり；

In formula (4), Y ¹ is a single bond, —O—, —COO—, —OCO—, or —OCOO—; Y ² is a single bond or alkylene having 1 to 20 carbon atoms, At least one —CH ₂ — may be replaced by —O—, —COO—, —OCO—, —CH═CH—, or —C≡C—; PG is represented by the formula (PG-1) to ( A polymerizable group represented by any one of PG-8);

In formulas (PG-1) to (PG-8),
Each R ⁵ is independently hydrogen, halogen, methyl, ethyl, or trifluoromethyl. )
[2]
The compound as described in [1] represented by following formula (1), (2), or (3).

(In Formula (1), (2), or (3),
A ¹ and A ² are each independently 1,4-phenylene, 1,4-cyclohexylene,
Pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone-2,7-diyl, carbazole-3,6-diyl, anthracene-2
6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl, in which at least one hydrogen is fluorine , Chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons, or 1 to 1 carbons May be replaced by 5 alkanoyl;
Z ¹ and Z ² are each independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, at least one —CH ₂ — is —O—, —CO—, —COO—, —
May be replaced by OCO-, -CH = CH-, -CF = CF-, or -C≡C-, in which hydrogen may be replaced by halogen;
n and m are each independently an integer of 0 to 3, and 1 ≦ m + n ≦ 4;
X ¹ is —NR ³ — or —S—, R ³ is hydrogen or a monovalent organic group;
Each X ² is independently —O—, —S—, or —NR ⁴ —, and R ⁴ is hydrogen or methyl;
R ¹ and R ² are each independently hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, or 1 to 20 carbons. Alkoxy, an alkyl ester having 1 to 20 carbon atoms, or a group represented by the formula (4);

In formula (4), Y ¹ is a single bond, —O—, —COO—, —OCO—, or —OCOO—; Y ² is a single bond or alkylene having 1 to 20 carbon atoms, At least one —CH ₂ — may be replaced by —O—, —COO—, —OCO—, —CH═CH—, or —C≡C—; PG is represented by the formula (PG-1) to ( A polymerizable group represented by any one of PG-8);

In formulas (PG-1) to (PG-8),
Each R ⁵ is independently hydrogen, halogen, methyl, ethyl, or trifluoromethyl. )
[3]
The compound according to [1] or [2], wherein R ¹ and / or R ² is a group represented by the formula (4).
[4]
The compound according to any one of [1] to [3], wherein X ¹ is any group of the following formulas (10) to (14).

(In the formulas (10) to (14),
A ¹ and A ² are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone -2,7-diyl, carbazole-3,6-diyl, anthracene-2
, 6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl, which contains at least one hydrogen, Fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons or 1 to 1 carbons May be replaced by 5 alkanoyl;
A ³ and A ⁴ are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone -2,7-diyl, carbazole-3,6-diyl, anthracene-2
, 6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl, which contains at least one hydrogen, Fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons or 1 to 1 carbons May be replaced by 5 alkanoyl;
Z ¹ , Z ² , and Z ³ are each independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, at least one —CH ₂ — is —O—, —CO—, —CO.
O—, —OCO—, —CH═CH—, —CF═CF— or —C≡C— may be substituted, in which hydrogen may be replaced with halogen;
n and m are each independently an integer of 0 to 3, and 1 ≦ m + n ≦ 4;
p is an integer from 0 to 2;
Y is each independently —O—, —S—, or —NR ⁴ —, and R ⁴ is hydrogen or methyl;
R ¹ and R ² are each independently hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, or 1 to 20 carbons. Alkoxy, an alkyl ester having 1 to 20 carbon atoms, or a group represented by the formula (4);

式（４）中、Ｙ^１は単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−または−ＯＣＯＯ−であり；Ｙ^２は単結合または炭素数１〜２０のアルキレンであり、該アルキレンにおいて少なくとも一つの−ＣＨ_２−は−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；ＰＧは式（ＰＧ−１）〜（ＰＧ−８）のいずれか１つで表される重合性の基であり；

In formula (4), Y ¹ is a single bond, —O—, —COO—, —OCO— or —OCOO—; Y ² is a single bond or an alkylene having 1 to 20 carbon atoms, One —CH ₂ — may be replaced by —O—, —COO—, —OCO—, —CH═CH— or —C≡C—; PG is represented by the formula (PG-1) to (PG-8) A polymerizable group represented by any one of

In formulas (PG-1) to (PG-8),
Each R ⁵ is independently hydrogen, halogen, methyl, ethyl, or trifluoromethyl;
In formula (10),
R ⁶ is hydrogen, and at least one —CH ₂ — is —O—, —CO—, —COO—, —OCO.
It is a C1-C10 alkyl, a fluoroalkyl group, or a cyano group which may be replaced by-, -CH = CH-, -CF = CF- or -C≡C-. )
[5]
A ¹ and A ² are each independently 1,4-phenylene or 1,4-cyclohexylene, in which at least one hydrogen is fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, Difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbon atoms, alkoxy having 1 to 5 carbon atoms, alkyl ester having 1 to 5 carbon atoms or alkanoyl having 1 to 5 carbon atoms may be substituted [1] to [1] 4].
[6]
A ¹ and A ² are 1,4-cyclohexylene and X ² is —O—.
The compound according to any one of [1] to [5].

[7]
A liquid crystal composition containing the compound according to any one of [1] to [6].
[8]
A polymer obtained by polymerizing the liquid crystal composition according to [7] by light irradiation.
[9]
An optically anisotropic film obtained by polymerizing the liquid crystal composition according to [7].
[10]
A liquid crystal display device having the optically anisotropic film according to [9].

The compound represented by the formula (I) of the present invention may be used alone or mixed with other known polymerizable liquid crystal compounds or a composition containing several of them and uniformly oriented in any form. It provides a material that reduces the wavelength dependence of the refractive index anisotropy of the material or exhibits reverse wavelength dispersion. In addition, a polymer obtained by polymerizing the liquid crystal composition of the present invention and a film containing the polymer are excellent in mechanical strength such as surface hardness as well as the effect on the wavelength dependency. Therefore, the polymer of the present invention is suitable for uses such as a retardation film, an optical compensation film, a polarizing element, a circular polarizing element, an elliptical polarizing element, a color compensation film, and a viewing angle compensation film.

Terms used in this specification are as follows. First, the meaning of the term “liquid crystalline” is not limited to having a liquid crystal phase. That is, a liquid crystal compound is a generic term for a compound having a liquid crystal phase and a compound having no liquid crystal phase but useful as a component of a liquid crystal composition. The liquid crystal phase is a nematic phase, a smectic phase, a cholesteric phase or the like, and often means a nematic phase. The liquid crystal lower limit temperature is a lower limit temperature indicating a liquid crystal phase, and is a temperature at which the liquid crystal phase transitions to a crystal. Polymerizability means the ability of a monomer to polymerize and give a polymer by means such as light, heat, or catalyst. A liquid crystal compound having a polymerizable group in the liquid crystal compound is called a polymerizable liquid crystal compound, and the polymerizable liquid crystal compound is included in the liquid crystal compound. The polymerizable compound means a compound having a polymerizable group that does not exhibit liquid crystallinity. A case where a compound has one polymerizable group may be referred to as a monofunctional or monofunctional compound. Moreover, when a compound has two or more polymeric groups, it may be called by the name corresponding to the number of polyfunctionality or polymeric groups. The compound represented by formula (1) may be referred to as compound (1). The compounds represented by other formulas may be referred to according to the same simplified method.

The term “at least one” used in describing the structure of a compound means that there is at least one of the number as well as the position. For example, the expression “at least one A may be replaced by B, C or D” means that at least one A is replaced by B, at least one A is replaced by C, and at least one A In addition to the case where A is replaced by D, the case where a plurality of A are replaced by at least two of B to D is also included. However, the definition that at least one —CH ₂ — may be replaced by —O— does not include such replacement that results in the bonding group —O—O—. Further, when at least one —CH ₂ — is replaced by —O—, the carbon number does not exceed the stated range.
For example, Z ¹ or Z ² in formula (1), (2), or (3) is alkylene having 1 to 20 carbons, and in this alkylene, at least one —CH ₂ — is replaced by —O—. However, the number of carbon atoms of the alkylene including the substitution with —O— does not exceed 20 in this case. This rule is the same for other definitions.

≪Compound≫
The liquid crystalline compound usually has a rod-like or disk-like molecular shape in which an aromatic ring or alicyclic ring is used as a core skeleton, and a flexible group composed of alkyl or the like is bonded thereto. The compound of the present invention has, as the core skeleton, formula (I) having a 5-membered ring structure such as 2,5-substituted pyrrole, 1,3-substituted isoindoles, or 2,5-substituted thiophenes, preferably formula The structure is (1), (2), or (3).

この式（Ｉ）、好ましくは式（１）、（２）、または（３）中、Ａ¹およびＡ²は、それぞれ独立して１，４−フェニレン、１，４−シクロへキシレン、ピリジン−２，５−ジイル、ナフタレン−２，６−ジイル、フルオレン−２，７−ジイル、フルオレノン−２，７−ジイル、カルバゾール−３，６−ジイル、アントラセン-２，６−ジイル、アントラセ
ン−１，６−ジイル、アントラキノン−２，６−ジイル、アントラキノン−１，５−ジイル、またはアゾベンゼン−４，４’−ジイルである。また、ｎまたはｍが２以上である場合、このＡ¹はその繰り返し毎に異なっていてもよい（Ａ²も同様である）。

In this formula (I), preferably in formula (1), (2) or (3), A ¹ and A ² are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine- 2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone-2,7-diyl, carbazole-3,6-diyl, anthracene-2,6-diyl, anthracene-1, 6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl. Further, when n or m is 2 or more, this A ¹ may be different for each repetition (the same applies to A ² ).

At this time, in order to increase the reverse wavelength dispersion of the refractive index anisotropy, it is preferable to select 1,4-cyclohexylene as A ¹ and / or A ² , and particularly Z ¹ and / or Z ^2. Is a single bond, A ¹ and / or A ² connected to X ² is preferably 1,4-cyclohexylene.

  In these divalent groups, at least one hydrogen is fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, The alkyl ester having 1 to 5 carbon atoms or the alkanoyl having 1 to 5 carbon atoms may be substituted. However, in order to impart high liquid crystallinity to the compound and to produce the compound at a low cost, it is preferable that these divalent hydrogens are not substituted with a group other than fluorine, and are not substituted with fluorine. Is more preferred.

Formula (I) Preferably, in Formula (1), (2), or (3), Z ¹ and Z ² are each independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, One —CH ₂ — is —O—, —CO—, —COO—, —OCO—, —CH═CH—,
-CF = CF-, or -C≡C- may be substituted, and in the alkylene, hydrogen may be substituted by halogen. However, both Z ¹ and Z ² are preferably single bonds in order to impart high liquid crystallinity to the compound and to produce the compound at low cost.
n and m are each independently an integer of 0 to 3, and 1 ≦ m + n ≦ 4.
In order to improve the liquid crystal properties of the compound of the formula (I), preferably the formula (1), (2), or (3), or to maintain compatibility when a liquid crystal composition is used, n + m Is particularly preferably 2 or 3.

R ¹ and R ² are each independently hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, or 1 to 20 carbons. Alkoxy, an alkyl ester having 1 to 20 carbon atoms, or a group represented by the formula (4).

In formula (4), Y ¹ is a single bond, —O—, —COO—, —OCO—, or —OCOO—; Y ² is a single bond or alkylene having 1 to 20 carbon atoms, At least one —CH ₂ — may be replaced by —O—, —COO—, —OCO—, —CH═CH—, or —C≡C—; PG is represented by the formula (PG-1) to ( It is a polymerizable group represented by any one of PG-8).

Here, each R ⁵ is independently hydrogen, halogen, methyl, ethyl, or trifluoromethyl.
E in formula (I) is hydrogen, or two E's are bonded to each other to form an aromatic ring having 14 or less carbon atoms (not including the carbon to which E is bonded). The aromatic ring is preferably a benzene ring, a naphthalene ring, or an anthracene ring.

The structure of the group represented by R ¹ or R ² is preferably selected from the group represented by the above formula (4) when the present technology is applied to film use. Here, as the selection of the polymerizable group represented by the formulas (PG-1) to (PG-8), an appropriate one can be selected depending on the film production conditions. However, when creating a film by photocuring that is usually used, an acrylic group or a methacryl group represented by the formula (PG-1), or an epoxy group represented by the formula (PG-3) or (PG-4) is selected. This is preferable from the viewpoints of high curability, solubility in a solvent, low crystallinity, and difficulty in forming orientation defects.

Formula (I) of the present invention, preferably, in the compound of Formula (1), (2), or (3), each X ² is independently —O—, —S—, or —NR ⁴ —. , R ⁴ is hydrogen or methyl.
X ¹ is —NR ³ — or —S—, and R ³ is hydrogen or a monovalent organic group. Incidentally, when ^{X 1} is -S-, it is preferred that ^{R 1} and ^{R 2} is a group represented by the formula (4). Limited to the selection of a monovalent organic group of R ³ is not, it can be widely selected from known monovalent organic group. At this time, it is preferable to select an aromatic monovalent organic group as R ^{3 in} order to obtain a material having a large refractive index anisotropy and reverse wavelength dispersion characteristic of the present invention. As specifically ^{X 1,} it is preferable to select one of the following formulas (10) to (14).

In formulas (10) to (14),
A ¹ and A ² are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone- 2,7-diyl, carbazole-3,6-diyl, anthracene-2
, 6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl or azobenzene-4,4′-diyl, in which at least one hydrogen is fluorine , Chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbon atoms, alkoxy having 1 to 5 carbon atoms, alkyl ester having 1 to 5 carbon atoms, or 1 to 5 carbon atoms May be replaced by alkanoyl.

A ³ and A ⁴ are each independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl, naphthalene-2,6-diyl, fluorene-2,7-diyl, fluorenone -2,7-diyl, carbazole-3,6-diyl, anthracene-2
, 6-diyl, anthracene-1,6-diyl, anthraquinone-2,6-diyl, anthraquinone-1,5-diyl, or azobenzene-4,4′-diyl, which contains at least one hydrogen, Fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons or 1 to 1 carbons May be replaced by 5 alkanoyl;

Z ¹ , Z ² , and Z ³ are each independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, at least one —CH ₂ — is —O—, —CO—, —CO.
O—, —OCO—, —CH═CH—, —CF═CF— or —C≡C— may be substituted, and in the alkylene, hydrogen may be substituted with a halogen.
n and m are each independently an integer of 0 to 3 and 1 ≦ m + n ≦ 4, and p is an integer of 0 to 2.
Y is independently —O—, —S—, or —NR ⁴ —, and R ⁴ is hydrogen or methyl.
R ¹ and R ² are the same as in the above formula (I).
R ⁶ is hydrogen, and at least one —CH ₂ — is —O—, —CO—, —COO—, —
An alkyl having 1 to 10 carbon atoms, a fluoroalkyl group, or a cyano group that may be replaced by OCO-, -CH = CH-, -CF = CF-, or -C≡C-.

Among the compounds represented by the above formula (I), preferably the formula (1), (2), or (3), it exhibits a good liquid crystal phase at a relatively low temperature, has a low clearing point, and dissolves in an organic solvent. From the viewpoint of high compatibility and high compatibility with other compounds, compounds represented by the following formula are preferred. In the following compounds, R ¹ and R ² are the same as described above, and R ¹⁰ is independently hydrogen, fluorine, chlorine, a methyl group, a methoxy group, a methylthio group, a hydroxy group, or an amino group.

The compound represented by the formula (I) of the present invention, preferably the formula (1), (2), or (3) can be synthesized by combining known organic synthetic chemistry techniques. Methods for introducing the desired end groups, rings and linking groups into the starting material are described by Houben-Wyle, Methods of Organic Chemistry, Georg Thieme Verlag, Stuttgart, Organic Syntheses, John Wily & Sons. , Inc.), Organic Reactions (John Wily & Sons Inc.), Comprehensive Organic Synthesis (Pergamon Press), and New Experimental Chemistry Course (Maruzen) Have been described. The structure of the synthesized compound can be confirmed by, for example, a proton NMR spectrum.

≪Liquid crystal composition≫
The liquid crystal composition of the present invention contains at least one compound represented by the formula (I). The liquid crystal composition of the present invention has a nematic or smectic liquid crystal phase at a relatively low temperature. When the liquid crystal composition of the present invention is coated on a plastic substrate that has been subjected to an alignment treatment such as a rubbing treatment or a support substrate whose surface is coated with a plastic thin film, a homogeneous alignment or a hybrid alignment is used. Become. Further, when a non-polymerizable or polymerizable optically active compound described later is added to the liquid crystal composition of the present invention, the twist alignment is obtained. When a compound having a cardo structure described later or a monofunctional liquid crystal compound is added to the liquid crystal composition of the present invention, homeotropic alignment is easily obtained.

  Constituents other than compound (I) include other liquid crystal compounds (excluding polymerizable liquid crystal compounds), other polymerizable liquid crystal compounds, surfactants, and other polymerizable compounds (however, polymerizable liquid crystal compounds are Ex.), Polymerization initiators, photosensitizers, chain transfer agents, antioxidants, UV absorbers, radical scavengers, light stabilizers, optically active compounds, silane coupling agents, solvents, and other additives May be contained within a range not impairing the effects of the present invention.

  Other liquid crystal compounds can be selected from compounds described in a liquid crystal compound database (LiqCryst, LCI Publisher GmbH, Hamburg, Germany). Among these, a compound represented by the following formula (LC) is preferable.

In the formula (LC), A ² is independently any divalent group selected from 1,4-phenylene, 1,4-cyclohexylene, pyridine-2,5-diyl and naphthalene-2,6-diyl. In the divalent group, at least one hydrogen is fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons , An alkyl ester having 1 to 5 carbon atoms, or an alkanoyl having 1 to 5 carbon atoms; Z ² is independently a single bond or alkylene having 1 to 20 carbon atoms, and in the alkylene, at least one —CH ₂ — is —
O—, —CO—, —COO—, —OCO—, —CH═CH—, —CF═CF—, or —C≡C— may be substituted, and at least one hydrogen is replaced with a halogen. B is an integer of 1 to 5; R ² is independently hydrogen, fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, alkyl having 1 to 10 carbons, Alternatively, it is alkoxy having 1 to 10 carbon atoms, and in the alkyl, at least one —CH ₂ — may be replaced by —CH═CH—.

  Specific examples of the compound represented by the above formula (LC) are shown below.

The liquid crystal composition of the present invention is the sum of the compound of the present invention represented by the formula (I) (preferably the formula (1), (2) or (3)) and the compound represented by the formula (LC). In an amount of 100% by weight, the compound of the present invention represented by the formula (I) (preferably the formula (1), (2) or (3))
90% by weight and preferably 10 to 99% by weight of the compound represented by the formula (LC) are contained. Furthermore, in order to reduce the wavelength dispersion of the liquid crystal composition without increasing the viscosity of the liquid crystal composition, the compound represented by the formula (I) is contained in an amount of 5 to 30% by weight and the compound represented by the formula (LC). It is more preferable to contain 70 to 95% by weight.

  As other polymerizable liquid crystal compounds, compounds represented by the following formulas (M1), (M2) and (M3) are preferable.

In formulas (M1), (M2) and (M3),
R ³ is hydrogen or methyl;
A ³ is independently 1,4-phenylene, 1,4-cyclohexylene, pyridine-
2,5-diylnaphthalene-2,6-diyl or fluorene-2,7-diyl, and in this 1,4-phenylene, at least one hydrogen is fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl. , Difluoromethyl, trifluoromethyl, alkyl having 1 to 5 carbons, alkoxy having 1 to 5 carbons, alkyl ester having 1 to 5 carbons, or alkanoyl having 1 to 5 carbons. In -2,7-diyl, at least one 9-position hydrogen may be replaced by fluorine or alkyl having 1 to 5 carbons;
Z ³ each independently represents a single bond, —C ₂ H ₄ —, —COO—, —OCO—, —C≡C—,
-CH = CHCOO -, - OCOCH = CH -, - COOC 2 H 4 -, - C 2 H 4 OCO -, - C 2 H 4 COO-, or -OCOC ₂ H ₄ - a and;
R ⁴ is cyano, alkyl having 1 to 10 carbons, and at least one CH ₂ — in the alkyl may be replaced by —O—;
Q is a single bond, —O—, —COO—, —OCO—, or —OCOO—;
p is an integer from 0 to 12; c is an integer from 1 to 3; d is an integer from 0 to 2.

  The compound (M1) is a monofunctional polymerizable liquid crystal compound, and it is easy to control the liquid crystal temperature range, optical characteristics, and orientation of the liquid crystal composition. The compound (M2) is a bifunctional polymerizable liquid crystal compound, and since this polymer has a three-dimensional structure, it becomes a hard polymer compared to the compound (M1) having one polymerizable group. The compound (M3) is a trifunctional polymerizable liquid crystal compound, and this polymer can form a stronger network, and becomes a harder polymer as compared with a compound having one or two polymerizable groups. . Hereinafter, the compounds (M1), (M2) and (M3) and compounds derived therefrom may be collectively referred to as the compound (M).

  Hereinafter, preferable examples of the compound (M1) are shown.

式（Ｍ１−１）〜（Ｍ１−２０）において、Ｒ³は独立して水素またはメチルであり、
ｐは独立して１〜１２の整数である。

In formulas (M1-1) to (M1-20), R ³ is independently hydrogen or methyl,
p is an integer of 1-12 independently.

  Hereinafter, preferable examples of the compound (M2) are shown.

式（Ｍ２−１）〜（Ｍ２−３０）において、Ｒ³は独立して水素またはメチルであり、
ｐは独立して１〜１２の整数である。式中に２つ以上のｐがあるとき、任意の２つ以上のｐは同一でもよく、異なっていてもよい。

In formulas (M2-1) to (M2-30), R ³ is independently hydrogen or methyl,
p is an integer of 1-12 independently. When there are two or more ps in the formula, any two or more ps may be the same or different.

  Hereinafter, preferable examples of the compound (M3) are shown.

式（Ｍ３−１）〜（Ｍ３−１０）において、Ｒ³は独立して水素またはメチルであり、
ｐは独立して１〜１２の整数である。式中に２つ以上のｐがあるとき、任意の２つ以上のｐは同一でもよく、異なっていてもよい。

In formulas (M3-1) to (M3-10), R ³ is independently hydrogen or methyl,
p is an integer of 1-12 independently. When there are two or more ps in the formula, any two or more ps may be the same or different.

  The polymerizable liquid crystal composition of the present invention comprises a compound of the present invention represented by the formula (I) (preferably the formula (1), (2), or (3)), the formula (M1), and (M2). And the compound of the present invention represented by the formula (I) (preferably the formula (1), (2), or (3)) in a total amount of 100% by weight of the compound represented by (M3). It is preferable to contain 1 to 99% by weight, and more preferably 10 to 80% by weight. Furthermore, in an optical compensation film manufactured using this material, it is more preferable to contain 50 to 80% by weight in order to reduce wavelength dispersion or increase reverse wavelength dispersion while maintaining the retardation value. When the content of each component in the liquid crystal composition is in the above range, a wavelength dispersion control of refractive index anisotropy can be easily performed, and a liquid crystal composition having good coating properties can be obtained. The effect of the polymer can be remarkably exhibited. Moreover, you may further contain the compound represented by the said formula (LC).

  The liquid crystal composition of the present invention may further contain a surfactant. As the surfactant, a nonionic surfactant is preferable. When the nonionic surfactant is contained in the liquid crystal composition, it has an effect of improving the smoothness of the coating film formed from the liquid crystal composition. is there.

  A preferred ratio in the case of adding a nonionic surfactant is the compound of the present invention represented by the formula (I) (preferably the formula (1), (2), or (3)) and, if necessary, The weight ratio with respect to the total weight of the compounds represented by the formulas (M1), (M2) and (M3) added is 0.0001 to 0.5. A more preferable range of the weight ratio is 0.0001 to 0.005.

Examples of the nonionic surfactant include a silicone-based nonionic surfactant, a fluorine-based nonionic surfactant, and a hydrocarbon-based nonionic surfactant.
Examples of the silicone-based nonionic surfactant include polyflow ATF-2, granol 100, granol 115, granol 400, granol 410, granol 435 manufactured by Kyoeisha Chemical Co., Ltd. based on unmodified silicone or modified silicone. , Granol 440, Granol 450, Granol B-1484, Polyflow KL-250, Polyflow KL-260, Polyflow KL-270, Polyflow KL-280, BYK-300, BYK-302, BYK-306, BYK-307, BYK- 310, BYK-315, BYK-320, BYK-322, BYK-323, BYK-325, BYK-
330, BYK-331, BYK-333, BYK-337, BYK-341, BYK-342, BYK-344, BYK-345, BYK-346, BYK-347, BYK-348, BYK-370, BYK-375, And BYK-377, BYK-378, BYK-3500, BYK-3510, and BYK-3570.

  Examples of the fluorine-based non-ionic surfactant include BYK-340, aftergent 251, aftergent 221MH, aftergent 250, FTX-215M, FTX-218M, FTX-233M, FTX-245M, FTX-290M, FTX. -209F, FTX-213F, Aftergent 222F, FTX-233F, FTX-245F, FTX-208G, FTX-218G, FTX-240G, FTX-206D, Aftergent 212D, FTX-218, FTX-220D, FTX-230D , FTX-240D, FTX-720C, FTX-740C, FTX-207S, FTX-211S, FTX-220S, FTX-230S, KB-L82, KB-L85, KB-L97, KB-L109, KB-L110, B-F2L, KB-F2M, KB-F2S, KB-F3M, and the like KB-FaM the like.

  Examples of the hydrocarbon-based nonionic surfactant include Polyflow No. 1 mainly composed of an acrylic polymer. 3, Polyflow No. 50EHF, Polyflow No. 54N, Polyflow No. 75, Polyflow No. 77, Polyflow No. 85HF, Polyflow No. 90, polyflow no. 95, Polyflow No. 99C, BYK-350, BYK-352, BYK-354, BYK-355, BYK-358N, BYK-361N, BYK-380N, BYK-381, BYK-392, and BYK-Silclean3700.

  The above-mentioned polyflow and granol are both names of products sold by Kyoeisha Chemical Co., Ltd. BYK is the name of a product sold by Big Chemie Japan. Footent, FTX and KB are names of products sold by Neos Co., Ltd.

Said surfactant may be used independently and may mix and use 2 or more.
Next, other polymerizable compounds, additives, and organic solvents are exemplified. These compounds may be commercially available products.

  Other polymerizable compounds include compounds such as vinyl derivatives, styrene derivatives, (meth) acrylic acid derivatives, oxirane derivatives, oxetane derivatives, sorbic acid derivatives, fumaric acid derivatives, and itaconic acid derivatives, which do not have liquid crystallinity. Is mentioned. Other polymerizable compounds having no liquid crystallinity include a compound having one polymerizable group, a compound having two polymerizable groups, and a polyfunctional compound having three or more polymerizable groups.

Examples of the compound having one polymerizable group include styrene, nucleus-substituted styrene, acrylonitrile, vinyl chloride, vinylidene chloride, vinyl pyridine, N-vinyl pyrrolidone, vinyl sulfonic acid, vinyl fatty acid (eg, vinyl acetate), α, β-ethylenically unsaturated carboxylic acid (eg, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, etc.), alkyl ester of (meth) acrylic acid (alkyl having 1 to 18 carbon atoms), (meth) acrylic Hydroxyalkyl esters of acids (hydroxyalkyls having 1 to 18 carbon atoms), aminoalkyl esters of (meth) acrylic acid (aminoalkyls having 1 to 18 carbon atoms), alkyl ethers containing ether oxygen of (meth) acrylic acid (ether oxygen) Containing alkyl having 3 to 18 carbon atoms, such as methoxyethyl ester, Toxiethyl ester, methoxypropyl ester, methyl carbyl ester, ethyl carbyl ester, and butyl carbyl ester), N-vinylacetamide, vinyl pt-butylbenzoate, vinyl N, N-dimethylaminobenzoate, vinyl benzoate, Vinyl pivalate, vinyl 2,2-dimethylbutanoate, vinyl 2,2-dimethylpentanoate, vinyl 2-methyl-2-butanoate, vinyl propionate, vinyl stearate, vinyl 2-ethyl-2-methylbutanoate, Dicyclopentanyloxylethyl (meth) acrylate, isobornyloxylethyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, dimethyladamantyl (meth) acrylate, dicyclopentanyl (meth) Acrylate, dicyclopentenyl (meth) acrylate, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl-2-hydroxyethyl Phthalic acid, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, polyethylene glycol having a polymerization degree of 1 to 100, polypropylene glycol, copolymer of ethylene oxide and propylene oxide, etc. A poly (alkylene glycol) mono (meth) acrylate ester or di (meth) acrylate ester, or a polyethylene glycol having a degree of polymerization of 1 to 100 whose end is capped with an alkyl group having 1 to 6 carbon atoms, Polypropylene Co - le, and polyalkylene glycol having a copolymer of ethylene oxide and propylene oxide - such as Le mono (meth) acrylic acid esters.

  Examples of the compound having two polymerizable groups include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, neopentyl glycol diacrylate, and dimethylol tricyclo. Decane diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, bisphenol A EO addition diacrylate, bisphenol A glycidyl diacrylate (Biscoat V # 700), polyethylene glycol di Examples thereof include acrylates and methacrylate compounds of these compounds.

  Examples of the compound having three or more polymerizable groups include pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylol EO-added tri (meth) acrylate, and tris (meth) acryloyloxyethylphosphine. Fate, tris ((meth) acryloyloxyethyl) isocyanurate, alkyl-modified dipentaerythritol tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (Meth) acrylate, alkyl-modified dipentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol hexa ( ) Acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, alkyl-modified dipentaerythritol penta (meth) acrylate, biscoat V # 802 (number of functional groups = 8), biscoat V # 1000 (number of functional groups = average 14), etc. Can be mentioned. “Biscoat” is a trade name of Osaka Organic Chemical Co., Ltd. Those having a functional group of 16 or more can be obtained by acrylating them using Boltorn H20 (16 functions), Boltorn H30 (32 functions), and Boltorn H40 (64 functions) sold by Perstorp Specialty Chemicals.

  Examples of other polymerizable compounds further include polymerizable fluorene derivatives having a cardo structure. These compounds are suitable for controlling the orientation direction and further increasing the degree of curing of the polymer. Examples of polymerizable fluorene derivatives having a cardo structure are shown in formulas (α-1) to (α-6).

また、その他の重合性化合物としては、さらに、ビスフェノール構造を有する重合性化合物が挙げられる。これらの化合物は、液晶組成物の被膜形成能や配向均一性の補助に適している。重合性ビスフェノール誘導体の例を式（Ｎ−１）〜（Ｎ−６）に示す。

In addition, examples of other polymerizable compounds include polymerizable compounds having a bisphenol structure. These compounds are suitable for assisting the film forming ability and alignment uniformity of the liquid crystal composition. Examples of the polymerizable bisphenol derivative are shown in formulas (N-1) to (N-6).

上記のその他の重合性化合物は単独で使用してもよく、２つ以上を混合して使用してもよい。また、これらの化合物は市販品であってもよい。

The other polymerizable compounds may be used alone or in combination of two or more. These compounds may be commercially available products.

  In order to optimize the polymerization rate, a polymerization initiator may be added to the liquid crystal composition. Examples of the polymerization initiator include a photo radical initiator. Examples of the photo radical polymerization initiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one (Darocur 1173), 1-hydroxycyclohexyl phenyl ketone, and 2,2-dimethoxy-1,2-diphenylethane. -1-one (Irgacure 651), 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184), Irgacure 127, Irgacure 500 (mixture of Irgacure 184 and benzophenone), Irgacure 2959, Irgacure 907, IRGACURE 369, IRGACURE 379, IRGACURE 754, IRGACURE 1300, IRGACURE 819, IRGACURE 1700, IRGACURE 1800, IRGACURE 1850, IRGACURE 1870, Rokyua 4265, Darocure MBF, Darocure TPO, Irgacure 784, Irgacure 754, Irgacure OXE01, and the like IRGACURE OXE02 the like. Both Darocur and Irgacure are names of products sold by BASF Japan.

Examples of the photo radical polymerization initiator include p-methoxyphenyl-2,4-bis (trichloromethyl) triazine, 2- (p-butoxystyryl) -5-trichloromethyl-1,3,4-oxadiazole. 9-phenylacridine, 9,10-benzphenazine, benzophenone / Michler's ketone mixture, hexaarylbiimidazole / mercaptobenzimidazole mixture, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, Benzyldimethyl ketal, 2-methyl-1- [4- (
Methylthio) phenyl] -2-morpholinopropan-1-one, 2,4-diethylxanthone / p-dimethylaminobenzoic acid methyl mixture, benzophenone / methyltriethanolamine mixture, and the like.

  The preferred addition amount of the radical photopolymerization initiator is the compound represented by the formula (I) (preferably the formula (1), (2), or (3)) and the formula (M1) added as necessary. , (M2) and (M3) in a weight ratio with respect to the total weight of the compounds, it is 0.0001 to 0.20. A more preferable range of this weight ratio is 0.001 to 0.15. A more preferable range is 0.01 to 0.15. The said photo radical initiator may be used independently, and may mix and use 2 or more. These polymerization initiators may be commercially available products.

  Further, a sensitizer may be added to these photo radical polymerization initiators. Examples of the sensitizer include isopropylthioxanthone, diethylthioxanthone, ethyl-4dimethylaminobenzoate (Darocur EDB), 2-ethylhexyl-4-dimethylaminobenzoate (Darocur EHA), and the like. These sensitizers may be used alone or in combination of two or more. These sensitizers may be commercially available products.

  A chain transfer agent may be added to the liquid crystal composition in order to control the polymerization reaction rate and mechanical properties of the polymer. By using a chain transfer agent, the reaction rate and chain length of the resulting polymer can be controlled. Increasing the amount of chain transfer agent decreases the polymerization reaction rate and decreases the length of the polymer chain. A preferred chain transfer agent is a thiol compound. Examples of monofunctional thiols are dodecanethiol, 2-ethylhexyl- (3-mercaptopropionate. Examples of multifunctional thiols are trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate), 1,4-bis (3-mercaptobutyryloxy) butane (Karenz MT BD1), pentaerythritol tetrakis (3-mercaptobutyrate) (Karenz MT PE1), and 1,3, 5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (Karenz MT NR1) “Karenz” is Showa Denko KK These chain transfer agents may be used alone or in combination of two or more. It may be used. These chain transfer agents may be commercially available.

  A polymerization inhibitor can be added to the liquid crystal composition in order to prevent initiation of polymerization during storage. Known polymerization inhibitors can be used, but preferred examples thereof include 2,5-di (t-butyl) hydroxytoluene (BHT), hydroquinone, methylene blue, diphenylpicric hydrazide (DPPH), phenothiazine, N, N-dimethyl. Nitroso compounds such as -4-nitrosoaniline, o-hydroxybenzophenone, and benzothiazine derivatives such as 2H-1,3-benzothiazine-2,4- (3H) dione.

  In order to improve the storage stability of the liquid crystal composition, a polymerization inhibitor may be added. When radicals are generated in the liquid crystal composition or the liquid crystal composition solution, the polymerization reaction of the polymerizable compound is promoted. In order to prevent this, it is preferable to add a polymerization inhibitor. As the polymerization inhibitor, a phenol-based antioxidant, a sulfur-based antioxidant, and a phosphoric acid-based antioxidant can be used.

In order to further improve the weather resistance of the liquid crystal composition, an ultraviolet absorber, a light stabilizer (radical scavenger), an antioxidant and the like may be added.
Examples of the ultraviolet absorber include Tinuvin PS, Tinuvin P, Tinuvin 99-2, Tinuvin 109, Tinuvin 213, Tinuvin 234, Tinuvin 326, Tinuvin 328, Tinuvin 329, Tinuvin 384-2, Tinuvin 571, Tinuvin 900, Tinuvin 928 , Tinuvin 1130, Tinuvin 400, Tinuvin 405, Tinuvin 460, Tinuvin 479
, Tinuvin 5236, ADK STAB LA-32, ADK STAB LA-34, ADK STAB LA-36, ADK STAB LA-31, ADK STAB 1413, ADK STAB LA-51 and the like. “Tinubin” is a trade name of BASF Japan, and “Adeka Stub” is a trade name of ADEKA. These ultraviolet absorbers may be used alone or in combination of two or more. These ultraviolet absorbers may be commercially available products.

  Examples of the light stabilizer include Tinuvin 111FDL, Tinuvin 123, Tinuvin 144, Tinuvin 152, Tinuvin 292, Tinuvin 622, Tinuvin 770, Tinuvin 765, Tinuvin 780, Tinuvin 905, Tinuvin 5100, Tinuvin 5050, 5060, Tinuvin 5151, Chimassorb 119FL, Kimasorb 944FL, Kimasorb 944LD, ADK STAB LA-52, ADK STAB LA-57, ADK STAB LA-62, ADK STAB LA-67, ADK STAB LA-63P, ADK STAB LA-68LD, ADK STAB LA-77, ADK STAB LA-82, ADK STAB LA-82 -87, Siasorb UV-3346 manufactured by Cytec, Goodlite UV-3034 manufactured by Goodrich, and the like. “Kimasorb” is a trade name of BASF Japan. These light stabilizers may be used alone or in combination of two or more. These light stabilizers may be commercially available products.

  Antioxidants include, for example, ADEKA ADK STAB AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, Sumitizer BHT and Sumitizer BBM sold by Sumitomo Chemical Co., Ltd. -S, and Sumilizer GA-80, and Irganox 1076, Irganox 1010, Irganox 3114, and Irganox 245 etc. which are sold from BASF Japan Ltd. are mentioned. These antioxidants may be used alone or in combination of two or more. These antioxidants may be commercially available products.

A silane coupling agent may be added to the liquid crystal composition in order to control the adhesion with the substrate. Examples of the silane coupling agent include vinyl trialkoxysilane, 3-isocyanatopropyltriethoxysilane, N- (2-aminoethyl) 3-aminopropyltrialkoxysilane, N- (1,3-dimethylbutylidene). -3- (trialkoxysilyl) -1-propanamine, 3-glycidoxypropyltrialkoxysilane, 3-chlorotrialkoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrialkoxysilane, etc. Can be mentioned. Also, in the above alkoxysilane, dialkoxymethylsilane in which one of the alkoxy groups (three) is replaced with methyl may be used as the silane coupling agent. These silane coupling agents may be used alone or in combination of two or more. These silane coupling agents may be commercially available products.

  The liquid crystal composition of the present invention comprises a liquid crystal composition and a solvent by diluting the liquid crystal composition with a solvent or dissolving each component of the liquid crystal composition in the solvent in order to facilitate coating. A solution of the liquid crystal composition may be prepared and applied. Examples of the solvent include ester solvents, amide solvents, alcohol solvents, ether solvents, glycol monoalkyl ether solvents, aromatic hydrocarbon solvents, halogenated aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents. Examples include solvents, halogenated aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, ketone solvents, and acetate solvents.

Examples of ester solvents include alkyl acetate (eg, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, 3-methoxybutyl acetate, isobutyl acetate, pentyl acetate and isopentyl acetate), ethyl trifluoroacetate, alkyl propionate (Example:
Methyl propionate, methyl 3-methoxypropionate, ethyl propionate, propyl propionate and butyl propionate), alkyl butyrate (eg methyl butyrate, ethyl butyrate, butyl butyrate, isobutyl butyrate and propyl butyrate), dialkyl malonate (eg : Diethyl malonate), alkyl glycolate (eg methyl glycolate and ethyl glycolate), alkyl lactate (eg methyl lactate, ethyl lactate, isopropyl lactate, n-propyl lactate, butyl lactate and ethylhexyl lactate), monoacetin, γ -Butyrolactone and γ-valerolactone are preferred.

  Examples of amide solvents include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N-methylpropionamide, N, N-dimethylformamide, N, N-diethylformamide, N, N-diethylacetamide, N, N-dimethylacetamidodimethylacetal, N-methylcaprolactam, dimethylimidazolidinone and the like are preferable.

  Examples of alcohol solvents include methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, t-butyl alcohol, sec-butyl alcohol, butanol, 2-ethylbutanol, n-hexanol, and n-heptanol. , N-octanol, 1-dodecanol, ethylhexanol, 3,5,5-trimethylhexanol, n-amyl alcohol, hexafluoro-2-propanol, glycerin, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol , Dipropylene glycol, tripropylene glycol, hexylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pen Njioru, 2,4-pentanediol, 2,5-hexanediol, 3-methyl-3-methoxybutanol, cyclohexanol and methylcyclohexanol is preferred.

  As the ether solvent, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, bis (2-propyl) ether, 1,4-dioxane, tetrahydrofuran (THF) and the like are preferable.

  Glycol monoalkyl ether solvents include ethylene glycol monoalkyl ether (eg, ethylene glycol monomethyl ether and ethylene glycol monobutyl ether), diethylene glycol monoalkyl ether (eg, diethylene glycol monoethyl ether), triethylene glycol monoalkyl ether, propylene glycol Monoalkyl ether (eg, propylene glycol monobutyl ether), dipropylene glycol monoalkyl ether (eg, dipropylene glycol monomethyl ether), ethylene glycol monoalkyl ether acetate (eg, ethylene glycol monobutyl ether acetate), diethylene glycol monoalkyl ether acetate ( Example: Diethylene glycol Ethyl ether acetate), triethylene glycol monoalkyl ether acetate, propylene glycol monoalkyl ether acetate (eg, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and propylene glycol monobutyl ether acetate), dipropylene glycol monoalkyl ether acetate ( Examples: Dipropylene glycol monomethyl ether acetate) and diethylene glycol methyl ethyl ether are preferred.

Aromatic hydrocarbon solvents include benzene, toluene, xylene, mesitylene, ethylbenzene, diethylbenzene, i-propylbenzene, n-propylbenzene, t-butylbenzene, s-butylbenzene, n-butylbenzene, and tetralin. . Preferred examples of the halogenated aromatic hydrocarbon solvent include chlorobenzene. As the aliphatic hydrocarbon solvent, hexane and heptane are preferable. As the halogenated aliphatic hydrocarbon solvent, chloroform, dichloromethane, carbon tetrachloride, dichloroethane, trichloroethylene, tetrachloroethylene and the like are preferable. As the alicyclic hydrocarbon solvent, cyclohexane, decalin and the like are preferable.

As the ketone solvent, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, methyl propyl ketone, and the like are preferable.
As the acetate solvent, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, methyl acetoacetate, 1-methoxy-2-propyl acetate and the like are preferable.

  From the viewpoint of the solubility of the liquid crystal compound, it is preferable to use an amide solvent, an aromatic hydrocarbon solvent, or a ketone solvent. Considering the boiling point of the solvent, an ester solvent, an alcohol solvent, an ether solvent, a glycol monoalkyl A combined use of an ether solvent is also preferred. Although there is no particular limitation regarding the selection of the solvent, when a plastic substrate is used as the supporting base, it is necessary to lower the drying temperature in order to prevent deformation of the substrate and to prevent the solvent from attacking the substrate. Solvents preferably used in such cases are aromatic hydrocarbon solvents, ketone solvents, ester solvents, ether solvents, alcohol solvents, acetate solvents, glycol monoalkyl ether solvents.

  The ratio of the solid content in the solution of the liquid crystal composition is 5 to 70% by weight based on the total weight of the solution. A preferable range of this ratio is 10 to 50% by weight, and a more preferable range is 10 to 40% by weight. These solvents may be used alone or in combination of two or more. These solvents may be commercially available products.

In the following description, a polymer (optical anisotropic film) obtained by polymerizing a liquid crystal composition may be referred to as a liquid crystal film. The liquid crystal film can be obtained as follows.
First, a liquid crystal composition is applied on a support substrate in a fluid state to form a coating film. When a solution of the liquid crystal composition is prepared, it is applied onto a support substrate and dried to form a coating film. The coating film is irradiated with light to polymerize the liquid crystal composition, and the nematic alignment formed in the liquid crystal state by the composition in the coating film is fixed.
Examples of the material of the support substrate that can be used include glass and plastic. Plastics include polyimide, polyamideimide, polyamide, polyetherimide, polyetheretherketone, polyetherketone, polyketonesulfide, polyethersulfone, polysulfone, polyphenylenesulfide, polyphenyleneoxide, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. , Polyacetal, polycarbonate, polyarylate, acrylic resin, polyvinyl alcohol, polypropylene, cellulose, triacetyl cellulose and partially saponified product thereof, epoxy resin, phenol resin, and cycloolefin resin. The support substrate is usually in the form of a sheet or film.

Examples of cycloolefin resins include, but are not limited to, norbornene resins and dicyclopentadiene resins. Among these, those having no unsaturated bond or hydrogenated unsaturated bond are preferably used. For example, hydrogenated products of ring-opening (co) polymers of one or more norbornene monomers, addition (co) polymers of one or more norbornene monomers, norbornene monomers and olefin monomers Addition copolymers with (ethylene, α-olefin, etc.), norbornene monomers and cycloolefin monomers (cyclopentene, cyclooctene, 5,6-dihydrodicyclopentadiene, etc.), and these Examples include modified products such as ZEONEX, ZEONOR (both trade names, manufactured by ZEON Corporation), ARTON (trade names, manufactured by JSR Corporation), TOPAS (trade names, manufactured by Ticona), APEL (trade name, manufactured by Mitsui Chemicals), Essina (trade name, manufactured by Sekisui Chemical Co., Ltd.), OPTOREZ (trade name, Hitachi) Adult Co., Ltd.) and the like.

A film made of these plastics (plastic film) that can be used as a support substrate may be a uniaxially stretched film or a biaxially stretched film. These films may be subjected to a surface treatment such as a hydrophilic treatment such as corona treatment or plasma treatment, or a hydrophobic treatment. There are no particular restrictions on the method of hydrophilization treatment, but corona treatment or plasma treatment is preferred, and a particularly preferred method is plasma treatment. For the plasma treatment, a method described in JP 2002-226616 A, JP 2002-121648 A, or the like may be used.
Further, an anchor coat layer may be formed in order to improve the adhesion between the liquid crystal film and the plastic film. As long as such an anchor coat layer enhances the adhesion between the liquid crystal film and the plastic film, there is no problem whether it is an inorganic material or an organic material. The plastic film may be a laminated film. Instead of plastic film, use a metal substrate such as aluminum, iron or copper with slit-shaped grooves on the surface, or a glass substrate such as alkali glass, borosilicate glass or flint glass whose surface is etched into a slit shape. You can also.

  In the case of forming a liquid crystal film of homogeneous alignment and hybrid alignment prior to the formation of the coating film of the liquid crystal composition, a physical or mechanical surface by rubbing or the like is formed on the support substrate such as a glass substrate or a plastic film. Process. When a homeotropic alignment liquid crystal film is formed, surface treatment such as rubbing is often not performed, but rubbing treatment may be performed in order to prevent alignment defects. Any method can be used for the rubbing treatment, but usually a rubbing cloth made of materials such as rayon, cotton, polyamide, etc. is applied to a metal roll etc., while rotating the roll while in contact with the support substrate or polymer film. A method of moving, a method of moving the support substrate side while fixing the roll, and the like are employed. The rubbing treatment may be performed directly on the support substrate, or a polymer film such as polyimide generally called an alignment film may be provided on the support substrate in advance, and the polymer film may be subjected to the rubbing treatment. The rubbing process is as described above. Depending on the type of the supporting substrate, silicon oxide can be inclinedly deposited on the surface to impart orientation ability.

  In addition, when forming a liquid crystal film of homogeneous alignment and hybrid alignment, in addition to performing physical and mechanical surface treatment by rubbing or the like, polyimide or polyacrylate or the like generally referred to as a photo-alignment film on the support substrate in advance. A polymer film may be provided, and the polymer film may be subjected to polarized UV treatment.

  Examples of coating methods for obtaining a uniform film thickness when applying a liquid crystal composition or a solution thereof include spin coating, micro gravure coating, gravure coating, wire bar coating, dip coating, and spray coating. A meniscus coating method and a die coating method. In particular, a wire bar coating method or the like in which a shear stress is applied to the liquid crystal composition at the time of application may be used for controlling the alignment of the liquid crystal composition without performing surface treatment of the substrate by rubbing or the like.

  When the solution of the liquid crystal composition of the present invention is applied, heat treatment may be performed in order to form a polymerizable liquid crystal layer having a uniform film thickness on the support substrate after application, that is, a layer of the liquid crystal composition. For the heat treatment, a hot plate, a drying furnace, blowing of hot air or hot air can be used.

The temperature and time when heat-treating the coating film, the wavelength of light used for light irradiation, the amount of light irradiated from the light source, etc. are the types and composition ratios of the compounds used in the liquid crystal composition, and whether a photopolymerization initiator is added. The preferred range varies depending on the amount of addition and the amount thereof. Accordingly, the conditions regarding the temperature and time of the heat treatment of the coating film described below, the wavelength of the light used for light irradiation, and the amount of light irradiated from the light source are merely an approximate range.

  The heat treatment of the coating film is preferably performed under the condition that uniform alignment of the polymerizable liquid crystal is obtained. You may carry out above the liquid crystal phase transition point of a liquid-crystal composition. An example of a heat treatment method is a method in which the coating film is heated to a temperature at which the liquid crystal composition exhibits a nematic liquid crystal phase to form a nematic alignment in the liquid crystal composition in the coating film. The nematic alignment may be formed by changing the temperature of the coating film within a temperature range in which the liquid crystal composition exhibits a nematic liquid crystal phase. This method is a method in which a nematic orientation is substantially completed in a coating film by heating the coating film to a high temperature range of the above temperature range, and then the order is further ordered by lowering the temperature. Regardless of which of the above heat treatment methods is employed, the heat treatment temperature is room temperature (25 ° C.) to 120 ° C. A preferable range of this temperature is room temperature (25 ° C.) to 80 ° C., and a more preferable range is room temperature (25 ° C.) to 60 ° C. The heat treatment time is 5 seconds to 2 hours. A preferable range of this time is 10 seconds to 40 minutes, and a more preferable range is 20 seconds to 20 minutes. In order to raise the temperature of the layer made of the liquid crystal composition to a predetermined temperature, the heat treatment time is preferably 5 seconds or more. In order not to lower the productivity, it is preferable to set the heat treatment time within 2 hours. In this way, the polymerizable liquid crystal layer according to the present invention is obtained.

The nematic alignment state of the liquid crystal compound formed in the polymerizable liquid crystal layer is fixed by polymerizing the liquid crystal compound by light irradiation. The wavelength of light used for light irradiation is not particularly limited. Electron beams, ultraviolet rays, visible rays, infrared rays (heat rays), etc. can be used. Usually, ultraviolet rays or visible rays may be used. The wavelength range is 150 to 500 nm. A preferable range is 250 to 450 nm, and a more preferable range is 300 to 400 nm.
Examples of light sources are low-pressure mercury lamps (sterilization lamps, fluorescent chemical lamps, black lights), high-pressure discharge lamps (high-pressure mercury lamps, metal halide lamps), short arc discharge lamps (ultra-high pressure mercury lamps, xenon lamps, mercury xenon lamps). is there. Preferred examples of the light source are a metal halide lamp, a xenon lamp, an ultrahigh pressure mercury lamp, and a high pressure mercury lamp. The wavelength region of the irradiation light source may be selected by installing a filter or the like between the light source and the polymerizable liquid crystal layer and passing only a specific wavelength region.
The amount of light irradiated from the light source is ² to 5000 mJ / cm ² when reaching the coating surface. A preferable range of the light amount is 10 to 3000 mJ / cm ² , and a more preferable range is 100 to 2000.
mJ / cm ² . It is preferable that the temperature condition at the time of light irradiation is set similarly to the above heat treatment temperature. The atmosphere of the polymerization environment may be any of a nitrogen atmosphere, an inert gas atmosphere, and an air atmosphere, but a nitrogen atmosphere or an inert gas atmosphere is preferable from the viewpoint of improving curability.

  When the polymerizable liquid crystal layer according to the present invention and a liquid crystal film obtained by polymerizing the polymerizable liquid crystal layer with light or heat are used in various optical elements, or when applied as an optical compensation element used in a liquid crystal display device, Control of the tilt angle distribution is extremely important.

One method of controlling the tilt angle is a method of adjusting the type and composition ratio of the liquid crystal compound used in the liquid crystal composition. The tilt angle can also be controlled by adding other components to the liquid crystal composition. The tilt angle of the liquid crystal film can also be controlled by the type and amount of the surfactant added as one of the other components, the type and amount of the solvent in the liquid crystal composition. The tilt angle of the liquid crystal film can also be controlled by the type of support substrate or polymer film, rubbing conditions, drying conditions of the coating film of the liquid crystal composition, heat treatment conditions, and the like. Furthermore, the irradiation atmosphere in the photopolymerization step after alignment, the temperature at the time of irradiation, and the like also affect the tilt angle of the liquid crystal film. That is, it can be considered that almost all conditions in the manufacturing process of the liquid crystal film affect the tilt angle to some extent. Therefore, by optimizing the liquid crystal composition and appropriately selecting various conditions for the production process of the liquid crystal film, an arbitrary tilt angle can be obtained.

  In the homogeneous orientation, the tilt angle is uniformly close to 0 degrees from the substrate interface to the free interface, and is particularly distributed in the range of 0 to 5 degrees. This alignment state is obtained by applying the liquid crystal composition of the present invention to the surface of a support substrate subjected to surface treatment such as rubbing to form a coating film.

An optically active compound may be added to the liquid crystal composition of the present invention. Preferred examples of the optically active compound are compounds represented by formulas (Op-1) to (Op-25). In these formulas, Ak represents alkyl having 1 to 15 carbons or alkoxy having 1 to 15 carbons, and Me, Et and Ph represent methyl, ethyl and phenyl, respectively. P ² is a polymerizable group, and is preferably a group containing (meth) acryloyloxy, vinyloxy, oxiranyl, or oxetanyl. The liquid crystal composition of the present invention may be used as a raw material of a polymer described below, or as a liquid crystal that is a constituent element of a liquid crystal display element.

具体例として、特開２０１１−１４８７６２号公報のｐ．７０の段落０１５９〜ｐ．８１の段落０１７０記載のものがある。

As a specific example, p. 70, paragraphs 0159-p. 81, paragraph 0170.

  A liquid crystal composition containing an appropriate amount of a compound having optical activity or a liquid crystal composition containing an appropriate amount of a polymerizable compound having optical activity is coated on an alignment-treated substrate and polymerized to form a helical structure ( A retardation film exhibiting a twist structure is obtained. The helical structure is fixed by polymerization of the liquid crystal composition. The properties of the obtained liquid crystal film depend on the helical pitch of the obtained helical structure. The helical pitch length can be adjusted depending on the type and amount of the optically active compound. One optically active compound may be added, but a plurality of optically active compounds may be used for the purpose of offsetting the temperature dependence of the helical pitch. The liquid crystal composition may contain other polymerizable compounds in addition to the optically active compound.

In the selective reflection of visible light, which is a characteristic of the liquid crystal film as described above, the helical structure acts on incident light and reflects circularly polarized light and elliptically polarized light. The selective reflection characteristic is expressed by λ = n · Pitch (λ is the central wavelength of selective reflection, n is the average refractive index, and Pitch is the helical pitch). By changing n or Pitch, the center wavelength (λ) and wavelength width are changed. (Δλ) can be appropriately prepared. In order to improve color purity, the wavelength width (Δλ) may be reduced, and when broadband reflection is desired, the wavelength width (Δλ) may be increased. Furthermore, this selective reflection is greatly influenced by the thickness of the polymer. In order to maintain color purity, the thickness must not be too small. In order to maintain uniform orientation, the thickness must not be too large. Accordingly, it is necessary to prepare an appropriate thickness, preferably 0.5 to 25 μm, and more preferably 1 to 10 μm.

  By making the helical pitch shorter than visible light, a negative C plate described in W. H. de Jeu, Physical Properties of Liquid Crystalline Materials, Gordon and Breach, New York (1980) can be prepared. In order to shorten the helical pitch, it can be achieved by using an optically active compound having a large twisting force (HTP: helical twisting power) and further increasing the amount of addition. Specifically, a negative C plate can be prepared by setting λ to 350 nm or less, preferably 200 nm or less. This negative type C plate is an optical compensation film suitable for VAN type, VAC type, OCB type and the like among liquid crystal display elements.

  The liquid crystal film may be used for a reflective film in which the reflection wavelength region as described in JP-A-2004-333671 is set to the near infrared (wavelength 800 to 2500 nm) by making the helical pitch longer than visible light. it can. Increasing the helical pitch can be achieved, for example, by using an optically active compound having a small twisting force or by reducing the amount of optically active compound added.

  Any optically active compound may be used as long as it induces a helical structure and can be appropriately mixed with the liquid crystal composition as a base. In addition, either a polymerizable compound or a non-polymerizable compound may be used, and an optimum compound can be added according to the purpose. In consideration of heat resistance and solvent resistance, a polymerizable compound is more preferable.

  Further, among the optically active compounds, those having a large twisting force (HTP: helical twisting power) are suitable for shortening the helical pitch. Representative examples of compounds having a large twisting force are disclosed in British Patent Application No. 2298202 and German Patent Application Publication No. 10221751.

  The thickness (film thickness) of the liquid crystal film varies depending on the retardation corresponding to the target element and the birefringence (optical anisotropy value) of the liquid crystal film. Accordingly, the thickness range is 0.05 to 100 μm as a guide, although it varies depending on the purpose. A more preferable range is 0.1 to 50 μm, and a further preferable range is 0.5 to 20 μm. The preferred haze value of the liquid crystal film is 1.5% or less, and the preferred transmittance is 80% or more. A more preferable haze value is 1.0% or less, and a more preferable transmittance is 95% or more. The transmittance preferably satisfies these conditions in the visible light region.

As the birefringence (optical anisotropy value) of the liquid crystal film is higher, the thickness can be reduced. The thinner the thickness, the better the optical properties such as haze value and transmittance.
The liquid crystal film is effective as an optical compensation element applied to liquid crystal display elements (particularly active matrix type and passive matrix type liquid crystal display elements). Examples of liquid crystal display element types suitable for using this liquid crystal film as an optical compensation film are IPS type (in-
Plane switching), OCB type (optically compensated birefringence), TN type (twisted nematic), STN type (super twisted nematic), ECB type (electrically controlled birefringence), DAP Type (alignment phase deformation effect), CSH type (color super homeotropic), VAN / VAC type (vertically oriented nematic / cholesteric), OMI type (optical mode interference), SBE type (super birefringence effect), etc. It is. Further, the liquid crystal film can be used as a phase letter for a display element such as a guest-host type, a ferroelectric type, or an antiferroelectric type. Note that the optimum values of parameters such as the thickness distribution and thickness of the tilt angle required for the liquid crystal film strongly depend on the type of liquid crystal display element to be compensated and its optical parameters, and therefore differ depending on the type of element.

The liquid crystal film can also be used as an optical element integrated with a polarizing plate or the like. In this case, the liquid crystal film is disposed outside the liquid crystal cell. On the other hand, since the liquid crystal film as the optical compensation element has little or no elution of impurities into the liquid crystal filled in the cell, it can be arranged inside the liquid crystal cell. For example, when the method disclosed in Japanese Patent Application Laid-Open No. 2008-01943 is applied, the function of the color filter can be further improved by forming the polymerizable liquid crystal layer of the present invention on the color filter.
The type of polarizing plate used in the optical element to which the present liquid crystal film can be applied is not particularly limited, and includes not only a widely used absorption type polarizing plate doped with iodine, but also a reflective polarizing type such as a wire grid polarizing plate. It can also be suitably used for optical compensation of the plate.

  The liquid crystal film may contain additives such as a dichroic dye. The homogeneously oriented liquid crystal film combined with the dichroic dye can also be used as an absorptive polarizing plate. The homogeneously oriented liquid crystal film combined with the fluorescent dye can also be used as a polarized light emitting film.

EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not restrict | limited by these Examples.
<Confirmation of compound structure>
The structure of the synthesized compound was confirmed by measurement of proton NMR (Bruker: DRX-500) at 500 MHz. The described numerical value represents ppm, s represents a singlet, d represents a doublet, t represents a triplet, and m represents a multiplet.

<Phase transition temperature>
A sample was placed on a hot plate of a melting point measuring apparatus equipped with a polarizing microscope, and the temperature was raised at a rate of 3 ° C./min. The temperature at which the phase transitions to another phase was measured. C is a crystal, G is a glass state, N is a nematic phase, S is a smectic phase, and I is an isotropic liquid. The NI point is the upper limit temperature of the nematic phase or the transition temperature from the nematic phase to the isotropic liquid. “C 50 N 63 I” indicates that the crystal transitioned to a nematic phase at 50 ° C. and the nematic phase to an isotropic liquid at 63 ° C. The parentheses indicate a monotropic liquid crystal phase.

<Polymerization conditions>
Under a nitrogen atmosphere, light having an intensity of 30 mW / cm ² (365 nm) was irradiated for 30 seconds using a 250 W ultra-high pressure mercury lamp (manufactured by Ushio Inc., Multilight-250) at room temperature.

<Evaluation of orientation>
(1) Creation of a rubbing-treated glass substrate with an alignment film A glass substrate having a thickness of 1.1 mm is spin-coated with a polyamic acid for low pretilt angle (horizontal alignment mode) (Rixon aligner: manufactured by PIA-5370 JNC). Then, after removing the solvent from the spin-coated coating film on an 80 ° C. hot plate, the coating film baked in an oven at 230 ° C. for 30 minutes was rubbed using a rayon cloth.

(2) Observation method by visual observation A substrate on which a retardation film was formed was sandwiched and observed between two polarizing plates arranged in crossed Nicols, and the substrate was rotated in a horizontal plane to confirm the light and dark state. The substrate on which the retardation film was formed was observed with a polarizing microscope, and the presence or absence of alignment defects was confirmed.

(3) Measurement with ellipsometer Using an OPTIPRO ellipsometer manufactured by Shintec Co., Ltd., the substrate on which the retardation film was formed was irradiated with light having wavelengths of 550 nm and 450 nm. Retardation of the incident angle of these lights at 90 ° with respect to the film surface was measured. Retardation (phase delay, also called retardation) is represented by Δn × d. The symbol Δn is the optical anisotropy value, and the symbol d is the thickness of the polymer film. As a chromatic dispersion characteristic, a value obtained from the following equation was used as an index.
Chromatic dispersion characteristic = retardation measured with 450 nm light / retardation measured with 550 nm light In other words, the smaller the chromatic dispersion characteristic value, the higher the reverse chromatic dispersion.

<Film thickness measurement>
The liquid crystal film layer of the glass substrate with the liquid crystal film was shaved, and the step was measured using a fine shape measuring device (Alphastep IQ, manufactured by KLA TENCOR Co., Ltd.).

<Pencil hardness>
It measured according to the method of JIS standard "JIS-K-5400 8.4 pencil scratch test".

  Example 1 The compound (1-22-1) shown below was synthesized as follows.

1-Phenylpyrrole-2,5-dicarboxylic acid synthesized according to J. Chem. Soc., Perkin Trans. 2, 2109 (1998); 1.0 g (4.3 mmol), trans-4- (trans-4-n- Pentylcyclohexyl) cyclohexanol; 2.3 g (9.1 mmol) and 4-N, N-dimethylpyridine; 0.1
To 1 g (0.87 mmol) of CH ₂ Cl ₂ (16 ml) solution, N, N′-Dicyclohexylcarbodiimide; 1.9 g (9.1 mmol) of CH ₂ Cl ₂ (4 ml) was added at 5 ° C. or less. After stirring overnight at room temperature, the reaction solution was filtered, and the filtrate was washed 3 times with pure water (30 ml). The organic layer was dried over anhydrous MgSO ₄ , filtered and the solvent was removed under reduced pressure. The residue was purified by column chromatography (SiO ₂ / toluene) and recrystallization (toluene / MeOH (methanol)) to obtain the desired product (1-22-1). Yield 2.4 g (80%).

The phase transition temperature and NMR analysis value of the obtained compound (1-22-1) are as follows.
Phase transition temperature (℃): C 157.4 N 173.0 I
¹ H-NMR (CDCl ₃ ; δ ppm): 7.39-7.46, 7.19-7.23 (m, 5H), 7.01 (s, 2H), 4.56-4.64 (m, 2H), 0.7-1.9 (m, 62H).

[Example 2]
The following compound (1-42-1) was synthesized as follows.

1-Phenylpyrrole-2,5-dicarboxylic acid; 1.0 g (4.3 mmol) and trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol; 3.3 g (9.1 mmol) In the same manner as in Example 1, the compound represented by formula (1-42-1) was synthesized. Yield 2.4 g (62%).
At this time, the raw material trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol is obtained by reacting trans-1,4-cyclohexan-diol with 4- (acryloxy-n-butyloxy) benzoic acid. ,Obtained.
¹ H-NMR (CDCl ₃ ; δ ppm): 8.15 (d, 4H, d = 8.80 Hz), 7.39-7.46, 7.19-7.23 (m, 5H), 7.01 (s, 2H), 7.00 (d, 4H, d = 8.70Hz), 6.40-6.44 (m, 2H), 6.11-6.16 (m, 2H), 5.83-5.85 (m, 2H), 4.58-4.63 (m, 4H), 4.26 (t, 4H, d = 6.15 Hz), 4.09 (t, 4H, d = 6.20Hz),
1.89-1.96 (m, 24H).

[Example 3]

Using 2,5-Dihydroxyhexa-2,4-dienedioic acid diethyl ester and 2-Aminofluorene according to the same method as J. Chem. Soc., Perkin Trans. 2, 2109 (1998), 1-Fluorenepyrrole-2, 5-dicarboxylic acid was obtained. Using this compound; 1.8 g (5.6 mmol) and trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol; 3.1 g (12 mmol), the compound ( 1-45-1) was obtained. Yield 2.7 g (Yield 4
7%).
¹ H-NMR (CDCl ₃ ; δ ppm): 8.15 (d, 4H, d = 8.80 Hz), 7.80 (d, 1H, d = 7.90 Hz), 7.79 (d, 1H, d = 6.40 Hz), 7.53 (d , 1H, d = 7.30Hz), 7.38 (s, 1H), 7.38 (t, 1H, d = 7.55), 7.30-7.32 (m, 1H), 7.20-7.30 (m, 1H), 7.02 (s, 2H ), 7.00 (d, 4H, d = 8.70Hz), 6.40-6.44 (m, 2H), 6.11-6.16 (m, 2H), 5.83-5.85 (m, 2H), 4.58-4.63 (m, 4H), 4.26 (t, 4H, d = 6.15Hz), 4.09 (t, 4H, d = 6.20Hz), 1.89-1.96 (m, 24H).

[Example 4]

Using 2,5-Dihydroxyhexa-2,4-dienedioic acid diethyl ester and 1,4-Phenylenediamine, according to the method described in J. Chem. Soc., Perkin Trans. 2, 2109 (1998), 1,1 ′ -(1,4-phenylene) bis (pyrrole-2,5-dicarboxylic acid) was obtained. This compound; 1.0 g (2.6
mmol) and trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol;
Compound (1-47-1) was obtained in the same manner as in Example 1 using 0 g (11 mmol).
Yield 2.1 g (45% yield).
¹ H-NMR (CDCl ₃ ; δ ppm): 8.13 (d, 8H, d = 8.70Hz), 7.20 (s, 4H), 7.01 (s, 4H), 7.00 (d, 8H, d = 8.70Hz), 6.40 -6.44 (m, 4H), 6.10-6.16 (m, 4H), 5.82-5.84 (m, 4H)
), 4.57-4.63 (m, 8H), 4.24 (t, 8H, d = 6.10Hz), 4.07 (t, 8H, d = 6.10Hz), 1.89-1.96 (m, 52H).

[Example 5]

Synthesis, 252 (1975), 1,3-Dimthoxycarbonylisoindole synthesized; 2.0 g (6
. 5 mmol) in a solution of EtOH (ethanol) / H ₂ O = 20 mL / 20 ml, NaO
H: 0.76 g (19 mmol) was used and hydrolyzed by stirring overnight at room temperature. After the reaction, EtOH was distilled off under reduced pressure, and 6N HCl was added to the residue to adjust to pH = 1. The resulting precipitate was filtered to obtain 1,3-Dicarbonylisoindole. Yield 1.6 g (89% yield).
This compound; 1.0 g (3.6 mmol) and trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol; 2.7 g (7.4 mmol) were reacted according to the same method as in Example 1. By doing so, a compound represented by the formula (2-18-1) was obtained. Yield 2.6g
(Yield 75%).

Tetrahedron Lett., 21, 1871 (1973)に従い合成した1,3-Benzothiophene dicarboxylic acid；１．０ｇ（４．５ｍｍｏｌ）とtrans-4-((4-acryloxy-n-butyloxy)phenylcarbonyloxy)cyclohexanol；３．４ｇ(９．４ｍｍｏｌ)とを、実施例１と同様な方法に従って反応させる事により、式（２−２４−１）で表される化合物を得た。収量３．４ｇ （収率 ８２％）。 [Example 6]

1,3-Benzothiophene dicarboxylic acid synthesized according to Tetrahedron Lett., 21, 1871 (1973); 1.0 g (4.5 mmol) and trans-4-((4-acryloxy-n-butyloxy) phenylcarbonyloxy) cyclohexanol; 4 g (9.4 mmol) was reacted according to the same method as in Example 1 to obtain a compound represented by the formula (2-24-1). Yield 3.4 g (82% yield).

[Example 7]
Compound (M2-7-1): Compound (M1-14-1): Compound (M1-16-1) = 50: 25: The weight ratio with respect to 100% by weight of the liquid crystal mixture (mother liquid crystal) of 25% by weight. 0.2 nonionic fluorosurfactant (manufactured by Neos Co., Ltd., trade name “Factent FTX-218”) and a weight ratio of 4 polymerization initiator Irgacure 907 (manufactured by Ciba Japan) were added. Furthermore, cyclopentanone / propylene glycol monomethyl ether acetate (PGMEA) = 7
/ 3 (weight ratio) was added to obtain an ink solution having a solid content of 30% by weight.

Next, this liquid crystal composition was applied onto a glass substrate with a rubbed alignment film by spin coating. The substrate was heated at 80 ° C. for 3 minutes, cooled at room temperature for 2 minutes, and the polymerizable liquid crystal layer from which the solvent was removed was polymerized in the air with ultraviolet rays to obtain an optically anisotropic film in which the alignment state of the liquid crystal was fixed. It was. When this film was observed with a polarizing microscope, it had no alignment defect and had a uniform homogeneous alignment. When the retardation (Re) of the optically anisotropic film was measured, the measured values of retardation at 90 degrees with respect to the film surface were 140.3 nm and 151.0 nm at 550 nm and 450 nm, respectively. Therefore, the wavelength dispersion characteristic was 1.0762.
Compound (1-22-1) was mixed with this mother liquid crystal so that the weight ratio of compound (1-22-1): mother liquid crystal = 21:79. Furthermore, the polymerization initiator and the surfactant were mixed at the same weight ratio as described above, and dissolved in a solvent to obtain an ink solution having a solid content of 30% by weight. The obtained ink solution was uniformly mixed without phase separation or the like.
This ink solution was applied to the substrate in the same manner as described above to obtain an optically anisotropic film. At this time, the applicability of the ink solution was good. Further, when the prepared optically anisotropic film was observed with a polarizing microscope, it had no alignment defect and had a homogeneous alignment. When the retardation (Re) of this film was measured, the measured values of retardation at 90 degrees with respect to the film surface were 145.8 nm and 154.6 nm at 550 nm and 450 nm, respectively. Therefore, the wavelength dispersion characteristic was 1.0604.

[Example 8]
The content or type of the compound of the present invention relative to the mother liquid crystal was changed, optically anisotropic films were prepared according to the same method as in Example 7, and the wavelength dispersion characteristics were measured. The results are shown in the table below. In addition, from these results, a value obtained by extrapolating the wavelength dispersion characteristic when each compound: base liquid crystal = 100: 0 weight ratio was also described.

なおこれらの膜を偏光顕微鏡観察したところ、配向欠陥がなく均一なホモジニアス配向
を有していた。

When these films were observed with a polarizing microscope, they had no homogeneous defects and had a homogeneous orientation.

[Comparative Example 1]

  It is the same as that of the said Example except having replaced with this invention compound and using the compound of the said formula (III-1), and using the liquid crystal composition of a formula (III-1): base liquid crystal = 20: 80 weight ratio. An optically anisotropic film was prepared by this method. When the retardation (Re) of this film was measured, the measured retardation values at 90 degrees with respect to the film surface were 147.4 nm and 157.1 nm at 550 nm and 450 nm, respectively. Therefore, the wavelength dispersion characteristic was 1.0658. From this result, it was 1.0238 when the wavelength dispersion characteristic at the time of formula (III-1): base liquid crystal = 100: 0 weight ratio was extrapolated.

  The optically anisotropic films of Examples 8 to 16 showed a low wavelength dispersion characteristic as compared with Comparative Example 1. This supports the effect of lowering the wavelength dispersion characteristics by incorporating the compound of the present invention into the liquid crystal composition, and the wavelength dispersion characteristics of the optically anisotropic film obtained by using the compound of the present invention. It became clear that control was possible.

<Mechanical properties of optically anisotropic film>
Table 2 shows the results of measuring the pencil hardness of the film surfaces of the optically anisotropic films prepared in Examples and Comparative Examples. Here, in Table 2, hardness (parallel) is a value measured in a direction parallel to the orientation direction of the optical anisotropic film, and hardness (vertical) is a value obtained by measuring a direction perpendicular to the orientation direction of the optical anisotropic film. .

  The optically anisotropic films of Examples 10, 12, 14, and 16 were superior in surface hardness as compared with Comparative Example 1. If the hardness of the film surface is strong, there is an advantage that it is difficult to cause scratches easily in the manufacturing process and that defective products are less likely to occur.

  The compound of the present invention has low wavelength dispersion characteristics or reverse wavelength dispersion characteristics. Since the liquid crystal composition using the compound can easily control wavelength dispersion characteristics and exhibits reverse wavelength dispersion in a single layer, an optically anisotropic film can be easily obtained. Moreover, the obtained optically anisotropic film has high mechanical strength. Therefore, the film containing this polymer is, for example, a retardation film, an optical compensation film, a reflection film, a selective reflection film, an antireflection film, a viewing angle compensation film, a liquid crystal alignment film, a polarizing element, a circularly polarizing element, and an elliptically polarized light. It is suitable for elements and the like, and display elements having these films or elements.

Claims (7)

The compound which is one of the compound groups represented by following formula (1-9)-(1-49), (2-10)-(2-24), and (3-1)-(3-2) .

(In the formulas (1-9) to (1-49), (2-10) to (2-24), and (3-1) to (3-2),
In these formulas, 1,4-phenylene or 1,4-cyclohexylene has at least one hydrogen atom selected from fluorine, chlorine, cyano, hydroxy, formyl, trifluoroacetyl, difluoromethyl, trifluoromethyl, May be substituted with 5 alkyl, 1-5 alkoxy, 1-5 alkyl ester, or 1-5 alkanoyl ;
R ¹ and R ² are each independently hydrogen, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, cyano, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, or 1 to 20 carbons. Alkoxy, an alkyl ester having 1 to 20 carbon atoms, or a group represented by the formula (4);

In formula (4), Y ¹ is a single bond, —O—, —COO—, —OCO—, or —OCOO—; Y ² is a single bond or alkylene having 1 to 20 carbon atoms, At least one —CH ₂ — may be replaced by —O—, —COO—, —OCO—, —CH═CH—, or —C≡C—; PG is represented by the formula (PG-1) to ( A polymerizable group represented by any one of PG-8);

In formulas (PG-1) to (PG-8),
R ⁵ is Ri each independently hydrogen, halogen, methyl, ethyl or trifluoromethyl der,
R ¹⁰ is independently hydrogen, fluorine, chlorine, methyl group, methoxy group, methylthio group, hydroxy group or amino group. ) The compound according to claim 1, wherein R ¹ and / or R ² is a group represented by the formula (4). The compound is represented by the formulas (1-9) to (1-39), (1-41), (1-44), (1-46), (2-10) to (2-17), (2 The compound of Claim 1 or 2 which is one of the compound groups represented by -22), (2-23), and (3-1) . The liquid crystal composition containing the compound as described in any one of Claims 1-3 . A polymer obtained by polymerizing the liquid crystal composition according to claim 4 by light irradiation. An optically anisotropic film obtained by polymerizing the liquid crystal composition according to claim 4 . A liquid crystal display device having the optically anisotropic film according to claim 6 .