TWI898112B - Polymerizable liquid crystal mixture, polymerizable liquid crystal composition - Google Patents

Abstract

The subject of the present invention is to provide a compound that can reduce the phase transition temperature of a liquid crystal composition without damaging the optical properties. The present invention relates to a polymerizable liquid crystal compound represented by formula (1), [In formula (1), k11, k12 and l each independently represent an integer of 1 or greater; ^B11 and ^B12 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 - ^CO- , -O- _CH2- , _-CH2 -O-, -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms; ^E11 and ^E12 each independently represent ^-CR1R2- _{, -CH2} - ^CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ¹¹ and G ¹² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R ^A11 and ^A12 each independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R3, ^-OR3 , a cyano group, or a nitro group; ^F11 and ^F12 each independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with ^-OR3 or a halogen atom, and the _-CH2- contained in the alkanediyl group may be substituted with ^-O- or -CO-; ^P11 and ^P12 each independently represent a hydrogen atom or a polymerizable group (wherein ^P1 and P12 each independently represent a hydrogen atom or a polymerizable group). ² is a polymerizable group); M each independently represents a divalent aliphatic alkyl group having 3 to 13 carbon atoms which may have a substituent; Ar ¹¹ and Ar ¹² each independently represent a divalent aromatic group which may have a substituent].

Description

Polymerizable liquid crystal mixture, polymerizable liquid crystal composition

The present invention relates to a polymerizable liquid crystal compound, a polymerizable liquid crystal composition comprising the polymerizable liquid crystal compound, a phase difference film, a polarizing plate, and an optical display formed from the polymerizable liquid crystal composition.

Optical films such as retardation films used in flat panel displays (FPDs) include those obtained by applying a coating liquid onto a supporting substrate and then polymerizing the coating liquid. The coating liquid is obtained by dissolving a polymerizable liquid crystal compound in a solvent. Previously, as polymerizable liquid crystal compounds, for example, nematic liquid crystal compounds with a rod-like structure in which approximately 2 to 4 six-membered rings are linked are known. On the other hand, one of the characteristics of a retardation film is that it is required to be able to perform polarization conversion in the entire wavelength range. For example, it is known that in a wavelength range where the value [Re(λ)/Re(550)] obtained by dividing the retardation value Re(λ) at a certain wavelength λ by the retardation value Re(550) at 550 nm is close to 1, or in a wavelength range where [Re(450)/Re(550)] is less than 1, which shows reverse wavelength dispersion, the same polarization conversion can theoretically be performed. Polymerizable liquid crystal compounds that can form such phase difference films are disclosed, for example, in Patent Documents 1 to 3. [Prior Art Document] [Patent Document]

[Patent Document 1] Japanese Patent Publication No. 2016-121339 [Patent Document 2] Japanese Patent Publication No. 2019-156733 [Patent Document 3] Japanese Patent Publication No. 2020-41026

[Identify the problem you want to solve]

When aligning a polymerizable liquid crystal compound, for example, after applying a coating liquid containing the polymerizable liquid crystal compound to a supporting substrate, it is necessary to heat it to a temperature higher than the phase transition temperature of the polymerizable liquid crystal compound to cause the phase transition. If the phase transition temperature of the polymerizable liquid crystal compound is high, there is a possibility of undesirable effects on the supporting substrate, or the useable supporting substrate is limited, and the heating temperature becomes higher, thereby reducing the manufacturing efficiency. In addition, if an additive is added to the polymerizable liquid crystal compound for the purpose of lowering the phase transition temperature, the molecular alignment of the liquid crystal compound may be disturbed by the additive, and the desired optical properties may not be obtained. Furthermore, even if the additive or the polymerizable liquid crystal compound is precipitated as crystals, the desired optical properties may not be obtained.

The object of the present invention is to provide a compound that can lower the phase transition temperature of a liquid crystal composition without compromising its optical properties. [Technical Solution]

The inventors of the present invention have conducted intensive research to solve the above problems, and as a result, have completed the present invention. Specifically, the present invention provides the following preferred forms. [1] A polymerizable liquid crystal compound represented by formula (1): [Chemical 1] [In formula (1), k11, k12 and l each independently represent an integer of 1 or greater; ^B11 and ^B12 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 - ^CO- , -O- _CH2- , _-CH2 -O-, -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms; ^E11 and ^E12 each independently represent ^-CR1R2- _{, -CH2} - ^CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ¹¹ and G ¹² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R wherein ^A11 and ^A12 independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R3, ^-OR3 , a cyano group, or a nitro group; wherein ^F11 and ^F12 independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with ^-OR3 or a halogen atom, and the _-CH2- contained in the alkanediyl group may be substituted with ^-O- or -CO-; wherein ^P11 and ^P12 independently represent a hydrogen atom or a polymerizable group (wherein ^P11 and P12 independently represent a hydrogen atom or a polymerizable group). At least one of ^{Ar 11} and Ar 12 is a polymerizable group); M each independently represents a divalent aliphatic hydrocarbon group having 3 to 13 carbon atoms which may have a substituent; Ar ¹¹ and Ar ¹² each independently represents a divalent aromatic group which may have a substituent]. [2] The polymerizable liquid crystal compound described in [1] above, wherein M in formula (1) is a divalent aliphatic hydrocarbon group having 2n carbon atoms (n represents an integer of 2 to 4) which may have a substituent. [3] The polymerizable liquid crystal compound described in [1] or [2] above, wherein Ar ¹¹ and Ar ¹² in formula (1) each independently represents a group represented by any one of the following formulas (Ar-1) to (Ar-5), [Chemical 2] [In formulas (Ar-1) to (Ar-5), * represents a bonding moiety; Q ¹ represents -S-, -O-, or -NR ¹¹ -, R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent; Q ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent; W ¹ and W ² independently represent -O-, -S-, -CO-, or -NR ¹¹ -, R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent; Y ¹ represents an alkyl group having 1 to 6 carbon atoms, an aromatic alkyl group or an aromatic heterocyclic group which may have a substituent; Y ² represents a CN group or an alkyl group having 1 to 12 carbon atoms which may have a substituent; the hydrogen atom contained in the alkyl group may be substituted with a halogen atom; the -CH ₂ contained in the alkyl group may be substituted with a halogen atom. - may be substituted with -O-, -CO-, -O-CO-, or -CO-O-; Z ¹ , Z ² , and Z ³ each independently represent a hydrogen atom, an aliphatic alkyl group or alkoxy group having 1 to 20 carbon atoms, an alicyclic alkyl group having 3 to 20 carbon atoms, a monovalent aromatic alkyl group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR ¹¹ R ¹² , or -SR ¹¹ ; Z ¹ and Z ² may be bonded to form an aromatic ring or an aromatic heterocyclic ring; R ¹¹ and R ¹² each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; Ax represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocyclic rings; Ay represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocyclic rings; Ax and Ay may be bonded to form a ring; Y ³ and Y ⁴ each independently represent a group selected from the following formula (Y ³ -1): [Chemical 3] [In formula (Y ³ -1), ^RY1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and the alkyl group may be substituted by one or more substituents X ³ , wherein the substituent X ³ represents a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorosulfanyl group, a nitro group, a cyano group, an isocyano group, an amino group, a hydroxyl group, a hydroxyl group, a methylamino group, a dimethylamino group, a diethylamino group, a diisopropylamino group, a trimethylsilyl group, a dimethylsilyl group, a thioisocyano group, or one -CH ₂ - group or two or more non-adjacent -CH ₂ - a linear or branched alkyl group having 1 to 20 carbon atoms which may be independently substituted by -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, wherein any hydrogen atom in the alkyl group may be substituted by a fluorine atom, or the group may be represented by -B ³¹ -F ³¹ -P ³¹ , wherein B 31, F 31 and P ³¹ are defined the same as B ¹¹ , F ¹¹ and P ¹¹ in the above formula (1), respectively, and may be the same as B ^{11 ,} F ¹¹ and P 11 in the formula (1), respectively ^{. 11} are the same or different; U ¹ represents an organic group having 2 to 30 carbon atoms having an aromatic alkyl group, any carbon atom of the aromatic alkyl group may be substituted with a heteroatom, and the aromatic alkyl group may be substituted with one or more of the above-mentioned substituents X ³ ; T ¹ represents -O-, -S-, -COO-, -OCO-, -OCO-O-, -NU ² -, -N=CU ² -, -CO-NU ² -, -OCO-NU ² -, or O-NU ² -, and U ² represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 3 to 12 carbon atoms, an organic group having 2 to 30 carbon atoms having an aromatic alkyl group (any carbon atom of the aromatic alkyl group may be substituted with a heteroatom), or (E ³¹ -A ³¹ ) _q -B ³² -F ³² -P ^32. The alkyl, cycloalkyl, cycloalkenyl and aromatic hydrocarbon groups may be unsubstituted or substituted with one or more substituents X3 ^. The alkyl group may be substituted by the cycloalkyl or cycloalkenyl group. One _-CH2- or two or more non-adjacent _-CH2- in the alkyl group may be independently substituted with -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -SO2-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-. One -CH2- or two _{or more} non-adjacent -CH in the cycloalkyl or cycloalkenyl group may be independently substituted with -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -SO2-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH= _CH- , -CF=CF- or -C≡C-. ₂ - may be independently substituted with -O-, -CO-, -COO-, -OCO- or O-CO-O-; E ³¹ , A 31 , B ³² , F ³² and P ³² are defined similarly to E ¹¹ , A ¹¹ , B ¹¹ , F 11 and P ¹¹ in formula (1), respectively, and may be the same as or different from ^the aforementioned E ¹¹ , A ¹¹ , ^{B 11 , F 11 and P 11} ; q represents an integer from 0 to 4; when there are plural E ³¹ and/or A ³¹ , they may be the same as or different; and U ¹ and U ² may be bonded to form a ring]. [4] A polymerizable liquid crystal composition comprising the polymerizable liquid crystal compound described in any one of [1] to [3] above and the polymerizable liquid crystal compound represented by formula (2), [Chemical 4] [In formula (2), k21 and k22 each independently represent an integer of 1 or greater; ^B21 and ^B22 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 -CO-, -O- ^CH2- , -CH2- _O- , -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom, _or ^an alkyl group having 1 to 4 carbon atoms; ^E21 and ^E22 each independently represent ^-CR1R2- , _-CH2 - _CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ²¹ and G ²² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R A ²¹ and A ²² each independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group; F ²¹ and F ²² each independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with -OR ³ or a halogen atom, and the -CH ₂ - contained in the alkanediyl group may be substituted with -O- or -CO-; P ²¹ and P ²² each independently represent a hydrogen atom or a polymerizable group (wherein P ²¹ and P ²² is a polymerizable group); Ar ²¹ each independently represents a divalent aromatic group which may have a substituent]. [5] The polymerizable liquid crystal composition as described in [4] above, wherein the ratio of the peak area of the polymerizable liquid crystal compound (1) to the total peak area of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) measured by liquid chromatography is 0.1% or more and 50% or less. [6] The polymerizable liquid crystal composition described in [4] or [5] above, wherein the groups represented by A ¹¹ , A ¹² , B ¹¹ , B ¹² , E ¹¹ , E ¹² , F ^{11 , F 12 ,} G ¹¹ , G ¹² , P ¹¹ and P ¹² in formula (1) are the same as the groups represented by A ²¹ , A ²² , B ²¹ , B ²² , E ²¹ , E ²² , F ²¹ , F ²² , G ²¹ , G ²² , P ²¹ and P ²² in formula (2), respectively, and the groups represented by Ar ¹¹ and Ar ¹² in formula (1) are the same as the group represented by Ar ²¹ in formula (2). [7] The polymerizable liquid crystal composition as described in any one of [4] to [6] above, further comprising a photopolymerization initiator and an organic solvent. [8] A phase difference film formed from the polymerizable liquid crystal composition as described in any one of [4] to [7] above. [9] A polarizing plate comprising the phase difference film as described in [8] above. [10] An optical display comprising the polarizing plate as described in [9] above. [Effects of the Invention]

According to the present invention, a compound can be provided that can lower the phase transition temperature of a liquid crystal composition without impairing the optical properties.

The following describes the embodiments of the present invention in detail. Furthermore, the scope of the present invention is not limited to the embodiments described herein, and various modifications can be made without departing from the spirit of the present invention.

<Polymerizable Liquid Crystal Compound> The polymerizable liquid crystal compound of the present invention is represented by formula (1): [Chemical 5] Hereinafter, the polymerizable liquid crystal compound of the present invention represented by formula (1) is also referred to as "polymerizable liquid crystal compound (1)".

In formula (1), k11 and k12 each independently represent an integer greater than 1, for example, an integer from 1 to 5. The sum of k11 and k12 is preferably 2 to 6, more preferably 2 to 4. From the perspective of excellent liquid crystal properties, k11 and k12 are each preferably independently 1 or 2. From the perspective of ease of production of the polymerizable liquid crystal compound (1), k11 and k12 are preferably the same number. In a preferred embodiment of the present invention, k11 and k12 are both 1.

In formula (1), l represents an integer greater than or equal to 1, and can be, for example, an integer from 1 to 8. From the viewpoint of excellent liquid crystallinity, l is preferably from 1 to 6.

In formula (1), ^B11 and ^B12 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , -O-, _-S- , -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO- ^NR1- , -NR2-CO-, -O- ^CH2- , -CH2- _O- , -S-CH2-, _-CH2 - _S- , or a single bond; _R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom, or an alkyl group having ¹ to 4 carbon atoms. ^B11 and ^B12 are each independently preferably -CO-O-, -O-CO-, -O-CO-O-, -CO- ^NR1- , -NR2-CO-, ^-CH2 - _O- , -O- _CH2- , -CH2- _S- , -S- _CH2- , or a single bond, and more preferably -O-CO- or -CO-O-. When plural ^B11 and ^B12 are present, they may be the same or different. From the perspective of ease of production of the polymerizable liquid crystal compound (1), plural ^B11s are preferably the same group, and plural ^B12s are preferably the same group. Furthermore, it is more preferred that ^B11 and ^B12 are the same.

Examples of the alkyl group having 1 to 4 carbon atoms represented by R ¹ and R ² include methyl, ethyl, propyl, butyl, isopropyl, isobutyl, and tert-butyl. Preferably, the alkyl group has 1 or 2 carbon atoms, and more preferably, the methyl group.

In formula (1), ^E11 and ^E12 independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO- ^NR1- , -NR2-CO-, -O- ^CH2- , -CH2 _- O-, -S- _CH2- , -CH2- _{S- ,} or a single bond. ^E11 and ^E12 are each independently preferably -CO-O-, -O-CO-, -O-CO-O-, -CO- ^NR1- , -NR2-CO-, ^-CH2 - _O- , -O- _CH2- , _-CH2-S- , -S- _CH2- , or a single bond, and more preferably -O-CO- or -CO-O-. From the perspective of ease of production of the polymerizable liquid crystal compound (1), ^E11 and ^E12 may be the same or different, but are preferably the same group.

G ¹¹ and G ¹² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms. A hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, and a -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-. R ³ represents an alkyl group having 1 to 4 carbon atoms, and a hydrogen atom contained in the alkyl group may be substituted with a fluorine atom. Examples of the divalent alicyclic alkyl group having 3 to 16 carbon atoms represented by G ¹¹ and G ¹² include the divalent alicyclic alkyl groups which may contain heteroatoms and are represented by formulas (g-1) to (g-10), preferably 5-membered or 6-membered alicyclic alkyl groups.

[Chemistry 6]

The groups represented by the above formulae (g-1) to (g-10) may be substituted by alkyl groups having 1 to 4 carbon atoms, such as methyl, ethyl, isopropyl, and t-butyl; alkoxy groups having 1 to 4 carbon atoms, such as methoxy and ethoxy; fluoroalkyl groups having 1 to 4 carbon atoms, such as trifluoromethyl; cyano; nitro; or halogen atoms, such as fluorine, chlorine, and bromine.

G ¹¹ and G ¹² are each preferably a 5-membered or 6-membered alicyclic alkyl group represented by any one of formulas (g-1) to (g-4), more preferably a 6-membered alicyclic alkyl group represented by formula (g-1), particularly preferably a cyclohexane-1,4-diyl group, and most preferably a trans-cyclohexane-1,4-diyl group. G ¹¹ and G ¹² may be the same or different, but from the perspective of ease of industrial production and productivity of the polymerizable liquid crystal compound (1), it is advantageous for them to be the same.

In formula (1), ^A11 and ^A12 each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms or a divalent aromatic alkyl group having 6 to 20 carbon atoms. The hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, ^-R3 , ^-OR3 , a cyano group or a nitro group.

Examples of the divalent alicyclic alkyl group having 3 to 16 carbon atoms or the divalent aromatic alkyl group having 6 to 20 carbon atoms represented by ^A11 and ^A12 include the alicyclic alkyl groups containing 5-membered or 6-membered rings represented by the above-mentioned formulas (g-1) to (g-10), or the aromatic alkyl groups having approximately 6 to 20 carbon atoms represented by formulas (a-1) to (a-8).

[Chemistry 7]

Furthermore, some of the hydrogen atoms in the groups exemplified above as ^A11 and ^A12 may be substituted by an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, or a t-butyl group; an alkoxy group having 1 to 4 carbon atoms, such as a methoxy group or an ethoxy group; a fluoroalkyl group having 1 to 4 carbon atoms, such as a trifluoromethyl group; a cyano group; a nitro group; or a halogen atom, such as a fluorine atom, a chlorine atom, or a bromine atom.

^A11 and ^A12 are preferably cyclohexane-1,4-diyl or 1,4-phenylene. When k11 and k12 are 1, ^A11 and ^A12 are each preferably 1,4-phenylene. When k11 and k12 are 2 or greater, ^A11 bonded to ^E11 and ^A12 bonded to ^E12 are preferably identical, and ^A11 bonded to ^E11 and ^A12 bonded to ^E12 are preferably 1,4-phenylene. When there are plural ^A11 and ^A12 , they may be the same or different.

In formula (1), ^F11 and ^F12 each independently represent an alkanediyl group having 1 to 12 carbon atoms. The hydrogen atom contained in the alkanediyl group may be substituted with ^-OR3 or a halogen atom, and the _-CH2- contained in the alkanediyl group may be substituted with -O- or -CO-. ^F11 and ^F12 each independently represent preferably an alkanediyl group having 3 to 10 carbon atoms, -( _CF2 ) _4- , -( _CF2 ) _6- , or -( _CF2 ) _8- , and more preferably an alkanediyl group having 4 or 6 carbon atoms [-( _CH2 ) _4- or -( _CH2 ) _6- ]. ^E11 and ^E12 may be the same or different. From the perspective of ease of industrial production and productivity of the polymerizable liquid crystal compound (1), it is advantageous for them to be the same.

^P11 and ^P12 each independently represent a hydrogen atom or a polymerizable group. At least one of ^P11 and ^P12 is a polymerizable group. From the perspective of the film hardness of a liquid crystal cured film obtained using the polymerizable liquid crystal compound, ^P11 and ^P12 are preferably both polymerizable groups.

The polymerizable group may be any reactive group capable of polymerizing the polymerizable liquid crystal compound (1). Specific examples include vinyl, vinyloxy, styryl, p-(2-phenylvinyl)phenyl, acryl, methacryl, acryloxy, methacryloxy, carboxyl, acetyl, hydroxyl, aminoformyl, N-alkylamino having 1 to 4 carbon atoms, amino, oxirane, cyclobutyl, formyl, isocyanate, and isothiocyanate. Furthermore, the polymerizable group may include an ether bond or an ester bond connecting the above-mentioned groups to ^F11 or ^F12 , preferably through an ether bond. P ¹¹ and P ¹² are preferably, for example, free radical polymerizable groups or cationic polymerizable groups suitable for photopolymerization. In particular, from the perspective of easy handling and production, an acryloyloxy group or a methacryloyloxy group is preferred, and an acryloyloxy group is more preferred.

In formula (1), M independently represents a divalent aliphatic hydrocarbon group having 3 to 13 carbon atoms, which may have a substituent. If M in formula (1) is a divalent aliphatic hydrocarbon group having 3 to 13 carbon atoms, it is easy to improve the solubility of other polymerizable liquid crystal compounds having a molecular structure similar to that of the polymerizable liquid crystal compound (1), such as the polymerizable liquid crystal compound represented by formula (2) below, in a solvent, and the phase transition temperature of the polymerizable liquid crystal compound is effectively lowered. Due to the excellent effect of lowering the phase transition temperature of the polymerizable liquid crystal compound, a liquid crystal cured film can be obtained from the polymerizable liquid crystal compound at a lower processing temperature. Therefore, it is also advantageous in terms of reducing the effect of heating on the optical properties of the liquid crystal cured film and improving manufacturing efficiency. This effect is particularly pronounced when compared to when M in formula (1) is a cyclic structure such as an alicyclic alkyl group or an aromatic alkyl group. The reason for this is not specifically defined, but it is speculated that since the group M positioned between the divalent aromatic groups (Ar ¹¹ and/or Ar ¹² ) does not have a rigid cyclic structure, the molecular flexibility increases, the solubility is easily improved, and the phase transition temperature is significantly lowered.

The divalent aliphatic hydrocarbon group having 3 to 13 carbon atoms may be linear or branched, and may be a saturated or unsaturated hydrocarbon group. A saturated hydrocarbon group is preferred, and a linear saturated hydrocarbon group is more preferred. Specific examples of the divalent aliphatic hydrocarbon group having 3 to 13 carbon atoms include alkanediyl groups having 3 to 13 carbon atoms, such as n-propylenediyl, isopropylenediyl, n-butylenediyl, n-pentanediyl, n-hexanediyl, n-heptanediyl, n-octanediyl, n-nonanediyl, and n-decanediyl. When plural M groups are present, they may be the same or different.

The hydrogen atom contained in the above-mentioned divalent aliphatic alkyl group having 3 to 13 carbon atoms may be replaced by a substituent. When M in formula (1) is a divalent aliphatic alkyl group having 3 to 13 carbon atoms and having a substituent, it is preferred that no cyclic structure exists in M including the substituent. In other words, the polymerizable liquid crystal compound (1) of the present invention does not contain a cyclic structure other than the alicyclic alkyl group or aromatic alkyl group represented by the group Ar ¹¹ in the structure represented by -(Ar ¹¹ -O-CO-M-CO-O)- in formula (1). As the substituent that the divalent aliphatic alkyl group having 3 to 13 carbon atoms may have, for example, a halogen atom, an alkoxy group having 1 to 4 carbon atoms, etc. can be mentioned. Furthermore, the number of carbon atoms contained in the substituent is not included in the number of carbon atoms contained in the aliphatic alkyl group represented by M in formula (1).

Furthermore, if M in formula (1) is a divalent aliphatic hydrocarbon group having 2n carbon atoms (n represents an integer from 2 to 4) that may have a substituent, the phase transition temperature of the polymerizable liquid crystal compound can be lowered and the solubility can be improved. Furthermore, the resulting liquid crystal cured film can exhibit superior reverse wavelength dispersion. The divalent aliphatic hydrocarbon group having 2n carbon atoms is preferably an alkanediyl group having 2n carbon atoms, specifically n-butanediyl, n-hexanediyl, and n-octanediyl.

In formula (1), M is preferably a divalent alkanediyl group having 3 to 11 carbon atoms which may have a substituent, more preferably a divalent alkanediyl group having 4 to 10 carbon atoms which may have a substituent, further preferably a divalent alkanediyl group having 4, 6 or 8 carbon atoms which may have a substituent, and particularly preferably n-butanediyl, n-hexanediyl and n-octanediyl.

In formula (1), Ar ¹¹ and Ar ¹² each independently represent a divalent aromatic group that may have a substituent. The divalent aromatic group that may have a substituent may be a divalent aromatic heterocyclic group or a divalent aromatic heterocyclic group. In the present invention, a divalent aromatic alkyl group that may have a substituent means a divalent linking group containing at least one aromatic alkyl ring, and a divalent aromatic heterocyclic group that may have a substituent means a divalent linking group containing at least one aromatic heterocyclic ring. The aromatic alkyl rings and aromatic heterocycles referred to herein refer to ring structures having a number of π electrons of [4n+2] (n represents an integer) according to Huckel's law. (In the case of aromatic heterocycles, Huckel's law is satisfied including unshared bonding electron pairs on heteroatoms such as -N= or -S-.) ^{Ar 11} and Ar ¹² may contain one aromatic alkyl ring or aromatic heterocycle, or two or more aromatic alkyl rings or aromatic heterocycles. When containing one aromatic alkyl ring or aromatic heterocycle, Ar ¹¹ and Ar ¹² are each independently a divalent aromatic alkyl group that may have a substituent, or a divalent aromatic heterocyclic group that may have a substituent. When containing two or more aromatic hydrocarbon rings or aromatic heterocycles, the compound may contain only multiple aromatic hydrocarbon rings or multiple aromatic heterocycles, or may contain one or more aromatic hydrocarbon rings and one or more aromatic heterocycles. The two or more aromatic hydrocarbon rings and/or aromatic heterocycles may be bonded to each other via a single bond, a divalent bond such as -CO-O-, or -O-.

Ar ¹¹ and Ar ¹² may be the same or different. From the perspective of ease of industrial production and productivity of the polymerizable liquid crystal compound (1), it is advantageous for them to be the same. Furthermore, when there are plural Ar ^11s , the plural Ar ^11s may be the same or different, but are preferably the same group. More preferably, the plural Ar ^11s are the same as Ar ^12s .

Examples of the aromatic hydrocarbon ring that may be included in Ar ¹¹ and Ar ¹² include a benzene ring, a naphthalene ring, and an anthracene ring, with a benzene ring and a naphthalene ring being preferred. Examples of the aromatic heterocyclic ring include a furan ring, a benzofuran ring, a pyrrole ring, an indole ring, a thiophene ring, a benzothiophene ring, a pyridine ring, a pyrrolidine ring, a pyrimidine ring, a triazole ring, a triazole ring, a pyrroline ring, an imidazole ring, a pyrazole ring, a thiazole ring, a benzothiazole ring, a thienothiazole ring, an oxazole ring, a benzooxazole ring, and a phenanthroline ring. When Ar ¹¹ and Ar ¹² include a nitrogen atom, the nitrogen atom preferably has π electrons.

Among them, Ar ¹¹ and Ar ¹² preferably have an aromatic heterocyclic ring containing at least two heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, more preferably have a thiazole ring, a benzothiazole ring, or a benzofuran ring, and even more preferably have a benzothiazole ring. Furthermore, when Ar ¹¹ and Ar ¹² have an aromatic heterocyclic ring containing at least two heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, the aromatic heterocyclic ring may constitute a divalent linking group that is directly bonded to -CO-O- or -O-CO- of G ¹¹ , M, or G ¹² in formula (1) to constitute the main chain of the compound represented by formula (1). The aromatic heterocyclic ring may be included as a substituent of the divalent linking group that is directly bonded to -CO-O- or -O-CO- of G ¹¹ , M, or G ^12. Preferably, the Ar ¹¹ or Ar ¹² group containing the aromatic heterocyclic ring is stereodisposed as a whole in a direction that is substantially orthogonal to the molecular alignment direction.

In formula (1), the total number _Nπ of π electrons contained in the divalent aromatic group optionally having a substituent represented by ^Ar11 and ^Ar12 is preferably 8 or more, more preferably 12 or more, particularly preferably 16 or more, and most preferably 20 or more. Furthermore, it is preferably 36 or less, more preferably 32 or less, further preferably 30 or less, particularly preferably 26 or less, and most preferably 24 or less.

Examples of the divalent aromatic group optionally having a substituent represented by Ar ¹¹ and Ar ¹² in formula (1) include the groups represented by the following formulae (Ar-1) to (Ar-5). [Chemical 8]

In formulas (Ar-1) to (Ar-5), * represents a bonding portion.

In formula (Ar-1), ^Q1 represents -S-, -O-, or ^-NR11- , and ^R11 represents a hydrogen atom or an optionally substituted C1-6 alkyl group. In formulas (Ar-3) and (Ar-4), ^Q2 represents a hydrogen atom or an optionally substituted C1-6 alkyl group.

In formula (Ar-2), W ¹ and W ² independently represent -O-, -S-, -CO-, or -NR ¹¹ -, and R ¹¹ represents a hydrogen atom or an optionally substituted alkyl group having 1 to 6 carbon atoms.

In formula (Ar-1), ^Y1 represents an alkyl group having 1 to 6 carbon atoms, an aromatic alkyl group which may have a substituent, or an aromatic heterocyclic group. In formula (Ar-2), ^Y2 represents a CN group or an alkyl group having 1 to 12 carbon atoms which may have a substituent. A hydrogen atom contained in the alkyl group may be substituted with a halogen atom, and _{a -CH2-} group contained in the alkyl group may be substituted with -O-, -CO-, -O-CO-, or -CO-O-.

In formulas (Ar-1) to (Ar-5), Z ¹ , Z ² , and Z ³ each independently represent a hydrogen atom, an aliphatic alkyl group or alkoxy group having 1 to 20 carbon atoms, an alicyclic alkyl group having 3 to 20 carbon atoms, a monovalent aromatic alkyl group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR ¹¹ R ¹² , or -SR ¹¹ . Z ¹ and Z ² may bond to each other to form an aromatic ring or an aromatic heterocyclic ring. R ¹¹ and R ¹² each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

In formulas (Ar-3) and (Ar-4), Ax represents an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocyclic rings, and Ay represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or an organic group having 2 to 30 carbon atoms and having at least one aromatic ring selected from the group consisting of aromatic hydrocarbon rings and aromatic heterocyclic rings. Ax and Ay may bond to form a ring.

In formula (Ar-1), ^Y is preferably an aromatic alkyl group or aromatic heterocyclic group which may have a substituent, more preferably an aromatic alkyl group having 6 to 12 carbon atoms or an aromatic heterocyclic group having 3 to 12 carbon atoms which may have a substituent. The aromatic alkyl group or aromatic heterocyclic group which may have a substituent is preferably an optionally substituted polycyclic aromatic alkyl group or a polycyclic aromatic heterocyclic group. In this specification, the term "polycyclic aromatic alkyl group" means an aromatic alkyl group having at least two aromatic rings, and examples thereof include condensed aromatic alkyl groups formed by condensing two or more aromatic rings and aromatic alkyl groups formed by bonding two or more aromatic rings. The term "polycyclic aromatic heterocyclic group" refers to an aromatic heterocyclic group having at least one heteroaromatic ring and at least one ring selected from the group consisting of aromatic rings and heteroaromatic rings. Examples include aromatic heterocyclic groups formed by condensing one or more aromatic heterocyclic rings with one or more rings selected from the group consisting of aromatic rings and heteroaromatic rings, and aromatic heterocyclic groups formed by bonding at least one heteroaromatic ring to at least one ring selected from the group consisting of aromatic rings and heteroaromatic rings.

Examples of the substituents that the aromatic alkyl group or aromatic heterocyclic group may have include a halogen atom, an alkyl group having 1 to 6 carbon atoms, a cyano group, a nitro group, a nitroso group, an alkylsulfinyl group having 1 to 6 carbon atoms, an alkylsulfonyl group having 1 to 6 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, an N-alkylamino group having 1 to 4 carbon atoms, an N,N-dialkylamino group having 2 to 8 carbon atoms, an amine sulfonyl group, an N-alkylamine sulfonyl group having 1 to 6 carbon atoms, and an N,N-dialkylamine sulfonyl group having 2 to 12 carbon atoms.

As Y ¹ , for example, groups represented by the following formulae (Y ¹ -1) to (Y ¹ -7) can be cited. [Chemical 9]

In formula (Y ¹ -1) to formula (Y ¹ -7), the * portion represents a linking portion.

In formulas (Y ¹ -1) to (Y ¹ -7), Z ⁴ each independently represents a halogen atom or an organic group having 1 to 20 carbon atoms, for example, preferably a fluorine atom, a chlorine atom, a bromine atom, a methyl group, an ethyl group, an isopropyl group, a sec-butyl group, a cyano group, a nitro group, a sulfonyl group, a nitroxy group, a carboxyl group, a trifluoromethyl group, a methoxy group, a thiomethyl group, an N,N-dimethylamino group, or an N-methylamino group; more preferably a halogen atom, a methyl group, an ethyl group, an isopropyl group, a sec-butyl group, a cyano group, a nitro group, or a trifluoromethyl group; and particularly preferably a methyl group, an ethyl group, an isopropyl group, a sec-butyl group, a pentyl group, or a hexyl group.

In formulas (Y ¹ -1) to (Y ¹ -7), V ¹ and V ² independently represent -CO-, -S-, -NR ¹³ -, -O-, -Se-, or -SO ₂ -, preferably -S-, -NR ¹³ -, or -O-. R ¹³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

In formulae (Y ¹ -1) to (Y ¹ -7), W ³ to W ⁷ each independently represent -C= or -N=.

In formula (Y ¹ -1) to formula (Y ¹ -7), at least one of V ¹ , V ² and W ³ to W ⁷ preferably represents a group containing S, N or O.

In formula (Y ¹ -1) to formula (Y ¹ -7), a each independently represents an integer from 0 to 3, preferably 0 or 1. b each independently represents an integer from 0 to 2, preferably 0.

Any of the groups represented by formulae (Y ¹ -1) to (Y ¹ -7) is preferably any of the groups represented by formulae (Y ¹ -8) to (Y ¹ -13), and more preferably a group represented by formula (Y ¹ -8).

[Chemistry 10]

In formulae (Y ¹ -8) to (Y ¹ -13), Z ⁴ , a, b, V ¹ , V ² and W ³ have the same meanings as Z ⁴ , a, b, V ¹ , V ² and W ³ in formulae (Y ¹ -1) to (Y ¹ -7).

Specific examples of Y ¹ include groups represented by formulas (ar-1) to (ar-840) described in Japanese Patent Application Laid-Open No. 2019-003177. Among them, groups represented by the following formula are preferred.

[Chemistry 11]

In one embodiment of the present invention, specific examples of the group represented by formula (Ar-1) include groups represented by the following formulae (Ar ¹ -1) to (Ar ¹ -126): wherein * represents a linking moiety.

[Chemistry 12]

[Chemistry 13]

[Chemistry 14]

[Chemistry 15]

[Chemistry 16]

[Chemistry 17]

In one embodiment of the present invention, specific examples of the group represented by formula (Ar-2) include groups represented by the following formulae (Ar ² -1) to (Ar ² -13): wherein * represents a linking moiety.

[Chemistry 18]

In one embodiment of the present invention, specific examples of the group represented by formula (Ar-3) include groups represented by the following formulae (Ar ³ -1) to (Ar ³ -23): wherein * represents a linking moiety.

[Chemistry 19]

[Chemistry 20]

The groups represented by formulae (Ar-1) to (Ar-4) may be groups described in, for example, Japanese Patent Application Publication No. 2011-207765, Japanese Patent Application Publication No. 2008-107767, or WO2014/010325, in addition to the groups specifically exemplified above.

In formula (Ar-5), Y ³ and Y ⁴ are independently selected from the groups represented by the following formula (Y ³ -1).

In formula (Y ³ -1), ^RY1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The alkyl group may be substituted by one or more substituents X ³ .

The substituent X ³ represents a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a pentafluorothio group, a nitro group, a cyano group, an isocyano group, an amino group, a hydroxyl group, a hydroxyl group, a methylamino group, a dimethylamino group, a diethylamino group, a diisopropylamino group, a trimethylsilyl group, a dimethylsilyl group, a thioisocyano group, or one -CH ₂ - or two or more non-adjacent -CH ₂ groups. - a linear or branched alkyl group having 1 to 20 carbon atoms which may be independently substituted by -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -O-CO-O-, -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF- or -C≡C-, wherein any hydrogen atom in the alkyl group may be substituted by a fluorine atom, or the group may be represented by -B ³¹ -F ³¹ -P ³¹ , wherein B 31, F 31 and P ³¹ are defined the same as B ¹¹ , F ¹¹ and P ¹¹ in the above formula (1), respectively, and may be the same as B ^{11 ,} F ¹¹ and P 11 in the formula (1), respectively ^{. 11Same} or different.

The substituent X ³ is preferably a fluorine atom, a chlorine atom, -CF ₃ , -OCF ₃ or a cyano group. ^RY1 is preferably an unsubstituted, hydrogen atom or a C 1-6 alkyl group substituted with one or more fluorine atoms, more preferably a hydrogen atom.

In formula (Y ³ -1), U ¹ represents an organic group having 2 to 30 carbon atoms and an aromatic alkyl group. Any carbon atom of the aromatic alkyl group may be substituted with a heteroatom. U ¹ represents an organic group having 2 to 30 carbon atoms and at least one aromatic ring selected from the group consisting of aromatic alkyl rings and aromatic heterocycles. The aromatic alkyl group may be substituted with one or more of the substituents X ³ described above.

From the perspective of improving wavelength dispersion, ^U1 is preferably an organic group having an aromatic heterocyclic ring in which one or more carbon atoms are substituted with a heteroatom. From the perspective of improving wavelength dispersion and exhibiting high birefringence, ^U1 is more preferably an organic group having an aromatic heterocyclic ring as a condensed ring of 5-membered and 6-membered rings.

Specifically, U ¹ is preferably a group represented by the following formula: In the following formula, these groups have a bond with T ¹ at any position.

[Chemistry 22]

In formula (Y ³ -1), T ¹ represents -O-, -S-, -COO-, -OCO-, -OCO-O-, -NU 2 -, -N=CU ² -, -CO-NU ² -, -OCO-NU ² -, or O-NU ² -; U ² represents a hydrogen atom, ^an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a cycloalkenyl group having 3 to 12 carbon atoms, an organic group having 2 to 30 carbon atoms having an aromatic hydrocarbon group (any carbon atom of the aromatic hydrocarbon group may be substituted with a heteroatom), or (E ³¹ -A ³¹ ) _q -B ³² -F ³² -P ³² . The alkyl group, cycloalkyl group, cycloalkenyl group and aromatic alkyl group may be unsubstituted or substituted with one or more substituents X ³ , and the alkyl group may be substituted with the cycloalkyl group or cycloalkenyl group. One _-CH2- or two or more non-adjacent _-CH2- in the alkyl group may be independently substituted with -O-, -S-, -CO-, -COO-, -OCO-, -CO-S-, -S-CO-, -SO2-, -O-CO- _O- , -CO-NH-, -NH-CO-, -CH=CH-COO-, -CH=CH-OCO-, -COO-CH=CH-, -OCO-CH=CH-, -CH=CH-, -CF=CF-, or -C≡C-. One _-CH2- or two or more non-adjacent _-CH2- in the cycloalkyl or cycloalkenyl group may be independently substituted with -O-, -CO-, -COO-, -OCO-, or O-CO-O-. E ³¹ , A ³¹ , B ³² , F ³² and P ³² are defined similarly to E ¹¹ , ^{A 11} , B 11 , F ¹¹ and P ¹¹ in formula (1), respectively, and may be the same as or different from the aforementioned E ¹¹ , A ¹¹ , B ¹¹ , F ¹¹ and P ¹¹ , respectively. q represents an integer from 0 to 4. When there are plural E ³¹ and/or A ³¹ , they may be the same as or different.

^T1 is preferably -O-, -S-, -N=CU ² - or -NU ² - in view of good birefringence and ease of synthesis. It is more preferably -O-, -S- or -NU ² - in view of ease of improving wavelength dispersion and birefringence.

U ² is preferably an alkyl or alkenyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 _{to 12} carbon atoms, or a cycloalkenyl group having 3 to 12 carbon atoms, which may be substituted with ^one or more of the above substituents X 3, and one -CH 2 - or two or more non-adjacent -CH ₂ - groups may be independently substituted with -O-, -CO-, -COO-, -OCO-, or -O-CO-O-, or the above alkyl or alkenyl group which may be substituted with such a cycloalkyl group, cycloalkenyl group, or aryl group.

In view of birefringence and solvent solubility, U ² is preferably a linear alkyl group having 1 to 20 carbon atoms, wherein the hydrogen atom may be substituted with a fluorine atom and one -CH ₂ - or two or more non-adjacent -CH ₂ - groups may be independently substituted with -O-, -CO-, -COO- or -OCO-.

U ¹ and U ² may bond to form a ring. In this case, for example, a cyclic group represented by -NU ¹ U ² or a cyclic group represented by -N=CU ¹ U ² can be exemplified.

Based on the considerations of easy availability of raw materials, good solubility, and exhibiting a relatively high birefringence, Y ³ and Y ⁴ are particularly preferably groups selected from the following formulae (Y ^3'- 1) to (Y ^3' -47).

[Chemistry 23]

[Chemistry 24]

[Chemistry 25]

From the viewpoint of improving the alignment of the polymerizable liquid crystal compound (1), facilitating industrial production, and improving productivity, the group represented by formula (Ar-5) may specifically include the following groups: * in (Ar ⁵ -1) to (Ar ⁵ -20) below represents a -CO-O- or -O-CO- bonding portion adjacent to G ¹¹ , M, or G ¹² , respectively.

[Chemistry 26]

[Chemistry 27]

[Chemistry 28]

Among formulae (Ar-1) to (Ar-5), formulae (Ar-1), (Ar-2), and (Ar-5) are preferred, formulae (Ar-1) and (Ar-5) are more preferred, and formula (Ar-1) is even more preferred.

Specific examples of *-O-CO-G ¹¹ -E ¹¹ -(A ¹¹ -B ¹¹ ) _k11 -F ¹¹ -P ¹¹ and *-O-CO-G ¹² -E ¹² -(A ¹² -B ¹² ) _k12 -F ¹² -P ¹² in formula (1) include the structures represented by formulas (R-1) to (R-100). In the formulas, * represents a bond to Ar ¹¹ or Ar ¹² , and n represents an integer from 2 to 12. The cyclohexane ring may be a trans isomer or a cis isomer, but is preferably a trans isomer.

[Chemistry 29]

[Chemistry 30]

[Chemistry 31]

[Chemistry 32]

[Chemistry 33]

[Chemistry 34]

[Chemistry 35]

[Chemistry 36]

[Chemistry 37]

The polymerizable liquid crystal composition of the present invention comprises the polymerizable liquid crystal compound (1) of the present invention and the polymerizable liquid crystal compound represented by formula (2) (hereinafter also referred to as "polymerizable liquid crystal compound (2)"). [In formula (2), k21 and k22 each independently represent an integer of 1 or greater; ^B21 and ^B22 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 -CO-, -O- ^CH2- , -CH2- _O- , -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom, _or ^an alkyl group having 1 to 4 carbon atoms; ^E21 and ^E22 each independently represent ^-CR1R2- , _-CH2 - _CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ²¹ and G ²² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R A ²¹ and A ²² each independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group; F ²¹ and F ²² each independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with -OR ³ or a halogen atom, and the -CH ₂ - contained in the alkanediyl group may be substituted with -O- or -CO-; P ²¹ and P ²² each independently represent a hydrogen atom or a polymerizable group (wherein P ²¹ and P ²² is a polymerizable group); Ar ²¹ each independently represents a divalent aromatic group which may have a substituent] By using the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in combination, the generation of alignment defects can be suppressed while effectively lowering the phase transition temperature of the polymerizable liquid crystal compound (2). The reason for this is unclear, but it is believed that when the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) of the present invention have structural units similar to each other, the mutual compatibility is improved by the polymerizable liquid crystal compound (1) having a higher molecular flexibility and in this state, a higher alignment order of the two polymerizable liquid crystal compounds can be maintained while significantly lowering the phase transition temperature. If phase transition can be performed at a lower temperature, liquid crystal cured films can be produced from polymerizable liquid crystal compounds at lower processing temperatures, which can reduce the effects of heating. In particular, from the viewpoint of suppressing the generation of alignment defects and easily lowering the phase transition temperature of the polymerizable liquid crystal compound [a mixture of polymerizable liquid crystal compounds (1) and (2)] without impairing the optical properties, preferred are -O-CO- ^G11 - ^E11- ( ^A11 - ^B11 ) _k11 - ^F11 - ^P11 and -O-CO- ^G12 - ^E12- ( ^A12 - ^B12 ) _k12 - ^F12 - ^P12 of the polymerizable liquid crystal compound (1) of the present invention, and -O-CO- ^G21 - ^E21- ( ^A21 - ^B21 ) _k21 - ^F21 - ^P21 and -O-CO- ^G22 - ^E22- ( ^A22 - ^B22 ) _k22 - ^F22 -P ²² have structural units that are similar to each other.

In formula (2), k21 and k22 each independently represent an integer greater than 1, for example, an integer from 1 to 5. The sum of k21 and k22 is preferably 2 to 6, more preferably 2 to 4. From the perspective of excellent liquid crystal properties, k21 and k22 are preferably independently 1 or 2. From the perspective of ease of production of the polymerizable liquid crystal compound (2), k21 and k22 are preferably the same number. In a preferred embodiment of the present invention, k21 and k22 are both 1. Furthermore, from the perspective of excellent liquid crystal properties, k11 and k12 in formula (1) and k21 and k22 in formula (2) are preferably all the same number, more preferably all 1.

As the groups represented by ^B21 , ^B22 , ^E21 , ^E22 , ^{G21, G22} , ^A21 , ^A22 , ^F21 , ^F22 , ^P21 , and ^P22 in formula (2), there can be exemplified the same groups as exemplified as the groups represented by ^B11 , ^B12 , ^E11 , ^E12 , G11, ^G12 , ^A11 , ^{A12 , F11 , F12} , ^P11 , and ^P12 in formula (1 ⁾ , and the same applies to preferred embodiments of each. Furthermore, as the group represented by Ar ²¹ in formula (2), the same groups as those exemplified as the groups represented by Ar ¹¹ and Ar ¹² in formula (1) can be exemplified, and the preferred embodiments thereof are also the same.

Preferably, the groups represented by ^A11 , ^A12 , ^B11 , ^B12 , E11, ^E12 , ^F11 , ^F12 , ^G11 , ^G12 , ^P11 , and ^P12 in formula (1) are the same as the groups represented by ^A21 , ^A22 , ^B21 , ^B22 , ^E21 , ^E22 , ^F21 , ^F22 , ^G21 , ^G22 , ^P21 , and ^P22 in formula (2), respectively, ^and the groups represented by ^Ar11 and ^Ar12 in formula (1) are the same as the group represented by ^Ar21 in formula (2). If the above-mentioned groups in formula (1) and the above-mentioned groups in formula (2) are in such a relationship, the compatibility between the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) can be easily improved, and while the alignment defects are suppressed, the phase transition temperature can be easily significantly reduced.

The contents of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in the polymerizable liquid crystal composition of the present invention can be appropriately determined within a range that can achieve the effects of the present invention, depending on the types of the polymerizable liquid crystal compound (1) and/or the polymerizable liquid crystal compound (2). The ratio of the peak area of the polymerizable liquid crystal compound (1) to the total peak area of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) measured by liquid chromatography (hereinafter also referred to as "area percentage value") is preferably 0.1% to 50%, more preferably 1% by mass or more, further preferably 2% by mass or more, and particularly preferably 3% by mass or more. If the content of the polymerizable liquid crystal compound (1) is greater than the above lower limit, the solubility of the polymerizable liquid crystal compound in the solvent is easily improved, and the phase transition temperature is easily sufficiently lowered. Furthermore, if the content of the polymerizable liquid crystal compound (1) is below the above-mentioned upper limit, the alignment state of the liquid crystal when a liquid crystal cured film is prepared from the polymerizable liquid crystal composition containing the polymerizable liquid crystal compound can be well maintained, thereby obtaining an optical film with excellent optical properties. Furthermore, in the case of containing a plurality of polymerizable liquid crystal compounds equivalent to the polymerizable liquid crystal compound (1) and/or the polymerizable liquid crystal compound (2), the area percentage value of the polymerizable liquid crystal compound (1) is calculated relative to the total peak area of all polymerizable liquid crystal compounds (1) and all polymerizable liquid crystal compounds (2). The area percentage value can be calculated based on the peak area measured by liquid chromatography. Specifically, it can be measured and calculated by the method described in the following embodiment.

The polymerizable liquid crystal composition of the present invention can significantly reduce the phase transition temperature compared to the case where the polymerizable liquid crystal compound (2) is used alone by combining the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2). For example, the phase transition temperature of the liquid crystal mixture of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) constituting the polymerizable liquid crystal composition of the present invention is preferably 153°C or less, more preferably 150°C or less, and further preferably 145°C or less. Furthermore, when the polymerizable liquid crystal compound (1) of the present invention and the polymerizable liquid crystal compound (2) are used in combination, the phase transition temperature can be reduced by preferably 8°C or more, more preferably 10°C or more, further preferably 12°C or more, and even more preferably 15°C or more, compared to the case where the polymerizable liquid crystal compound (2) is used alone. Furthermore, in the present invention, the phase transition temperature of the polymerizable liquid crystal compound can be measured by the method described in the following examples. When two or more polymerizable liquid crystal compounds are included, the phase transition temperature is measured using a polymerizable liquid crystal compound (mixture) having the same composition as the polymerizable liquid crystal compound constituting the polymerizable liquid crystal composition.

Furthermore, the polymerizable liquid crystal composition of the present invention comprises a polymerizable liquid crystal compound (1) and a polymerizable liquid crystal compound (2) in combination, and thus has a better effect of improving the solubility of the polymerizable liquid crystal compound in the solvent than when the polymerizable liquid crystal compound (2) is used alone.

The production methods of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) constituting the polymerizable liquid crystal composition of the present invention are not particularly limited, and they can be produced by appropriately combining known organic synthesis reactions described in Methoden der Organischen Chemie, Organic Reactions, Organic Syntheses, Comprehensive Organic Synthesis, New Experimental Chemistry Lectures, etc. (e.g., condensation reaction, esterification reaction, Williams reaction, Ulmann reaction, Wittig reaction, Schiff base formation reaction, benzylation reaction, Sonogashira reaction, Suzuki-Miyaura reaction, Negishi reaction, Kumada reaction, Hikariyama reaction, Buchwald-Hartwig reaction, Friedel-Crafts reaction, Heck reaction, aldol reaction, etc.) according to their structures.

For example, a polymerizable liquid crystal compound (1) in which A ¹¹ and A ¹² , B ¹¹ and B ¹² , E ¹¹ and E ¹² , F ¹¹ and F ¹² , G ¹¹ and G ¹² , P ¹¹ and P ¹² , and Ar ¹¹ and Ar ¹² are respectively identical in formula (1) can be produced by subjecting a compound represented by formula (1-1) (hereinafter also referred to as “compound (1-1)”), a compound represented by formula (1-2) (hereinafter also referred to as “compound (1-2)”), and a compound represented by formula (1-3) (hereinafter also referred to as “compound (1-3)”) to an esterification reaction. Furthermore, P, F, B, A, E, and G in formula (1-1) are the same as those defined as P ¹¹ and P ¹² , F ¹¹ and F ¹² , B ¹¹ and B ¹² , A ¹¹ and A ¹² , E ¹¹ and E ¹² , and G ¹¹ and G ¹² in formula (1), respectively. Furthermore, M in formula (1-2) and Ar in formula (1-3) are the same as those defined as M, Ar ¹¹ , and Ar ¹² in formula (1), respectively. P, F, B, A, E, G, and Ar are determined according to the desired polymerizable liquid crystal compound (1) and polymerizable liquid crystal compound (2).

[Chemistry 39]

[Chemistry 40]

[Chemistry 41]

The reaction of compounds (1-1) to (1-3) is preferably carried out in the presence of a condensing agent. Examples of the condensing agent include 1-cyclohexyl-3-(2-oxo-1,2-dopamine-1-ylethyl)carbodiimide methyl-p-toluenesulfonate, dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (some water-soluble carbodiimides can be used as WSC). carbodiimide, water-soluble carbodiimide (commercially available), bis(2,6-diisopropylphenyl)carbodiimide, bis(trimethylsilyl)carbodiimide, N,N'-diisopropylcarbodiimide and other carbodiimides, 2-methyl-6-nitrobenzoic anhydride, 2,2'-carbonylbis-1H-imidazole, 1,1'-ethylenediimidazole , diphenylphosphinoyl azide, 1-(4-nitrobenzenesulfonyl)-1H-1,2,4-triazole, 1H-benzotriazol-1-yloxytripyrrolidinophosphonium hexafluorophosphate, 1H-benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate, N,N,N',N'-tetramethyl-O-(N-succinimidyl)uronium tetrakis(II) Fluoroborate, N-(1,2,2,2-tetrachloroethoxycarbonyloxy)butanediimide, N-benzyloxycarbonylbutanediimide, O-(6-chlorobenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate, O-(6-chlorobenzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate, 2 -Bromo-1-ethylpyridinium tetrafluoroborate, 2-chloro-1,3-dimethylimidazolinium chloride, 2-chloro-1,3-dimethylimidazolinium hexafluorophosphate, 2-chloro-1-methylpyridinium iodide, 2-chloro-1-methylpyridinium p-toluenesulfonate, 2-fluoro-1-methylpyridinium p-toluenesulfonate, pentachlorophenyl trichloroacetate, etc. Based on reactivity, cost, and a wide range of available solvent options, preferred condensation agents include dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, bis(2,6-diisopropylphenyl)carbodiimide, bis(trimethylsilyl)carbodiimide, N,N'-diisopropylcarbodiimide, and 2,2'-carbonylbis-1H-imidazole.

The polymerizable liquid crystal compound (2) can be produced, for example, by reacting the above-mentioned compound (1-1) and compound (1-3).

In the present invention, the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) constituting the polymerizable liquid crystal composition can be prepared separately and then mixed to prepare a liquid crystal mixture for use. Alternatively, a liquid crystal mixture of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) can be obtained by reacting the above-mentioned compounds (1-1) to (1-3) at appropriate ratios. By not isolating each polymerizable liquid crystal compound from the obtained liquid crystal mixture, but mixing the liquid crystal mixture with the polymerizable liquid crystal compound (1) or the liquid crystal mixture with the polymerizable liquid crystal compound (2) as needed, the contents of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in the above liquid crystal mixture can be controlled, thereby preparing the desired polymerizable liquid crystal mixture. If the former method is used, it is easy to adjust the content of the polymerizable liquid crystal compound (1) or the polymerizable liquid crystal compound (2) to the desired range, and it is easy to control the solvent solubility of the polymerizable liquid crystal compound. On the other hand, if the polymerizable liquid crystal mixture is prepared by the latter method, the synthesis is simple and the polymerizable liquid crystal composition can be produced more efficiently.

When a polymerizable liquid crystal compound (1) and a polymerizable liquid crystal compound (2) are prepared into a liquid crystal mixture, the amount of the compound (1-2) to be reacted is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the compound (1-1). Furthermore, the amount of the compound (1-3) to be reacted is preferably 1 to 70 parts by mass, more preferably 10 to 65 parts by mass, relative to 100 parts by mass of the compound (1-1). By adjusting the amounts of the compound (1-1), the compound (1-2), and the compound (1-3) within the above range, a liquid crystal mixture containing the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) at a desired ratio can be easily prepared.

The polymerizable liquid crystal composition of the present invention may contain polymerizable liquid crystal compounds other than the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) within a range that does not affect the effects of the present invention. Examples of such polymerizable liquid crystal compounds include compounds described in 3.2 Non-chiral Rod-shaped Liquid Crystal Molecules and 3.3 Chiral Rod-shaped Liquid Crystal Molecules in Chapter 3, "Molecular Structure and Liquid Crystallinity," of the Liquid Crystal Handbook (edited by the Liquid Crystal Handbook Editorial Committee, published by Maruzen Co., Ltd. on October 30, 2000); compounds described in Japanese Patent Publication No. 2010-31223; polymerizable liquid crystal compounds that exhibit negative wavelength dispersion when formed into liquid crystal cured films, and polymerizable liquid crystal compounds that exhibit positive wavelength dispersion, as described in Japanese Patent Publication No. 2011-207765 and Japanese Patent No. 5962760, etc.

When the polymerizable liquid crystal composition of the present invention contains a polymerizable liquid crystal compound other than the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2), the content thereof is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and further preferably 5 parts by mass or less, relative to 100 parts by mass of the total of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2). In particular, if the content of a liquid crystal compound having a molecular structure significantly different from that of the polymerizable liquid crystal compound (1) or the polymerizable liquid crystal compound (2) is too high, there is a risk of causing phase separation and impairing the appearance. Therefore, the polymerizable liquid crystal compound constituting the polymerizable liquid crystal composition of the present invention is preferably a polymerizable liquid crystal compound having a structure similar to that of the polymerizable liquid crystal compound (1). Furthermore, the above-mentioned "similar" refers to, for example, a case where the polymerizable liquid crystal compound (1) has a common structure with the moiety represented by -O-CO- ^G11 - ^E11- ( ^A11 - ^B11 ) _k11 - ^F11 - ^P11 , -O-CO- ^G12 - ^E12- ( ^A12 - ^B12 ) _k12 - ^F12 - ^P12 , or the moiety represented by ^Ar11 or ^Ar12. The above-mentioned "substantially comprising" means that the content of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) is 90% by mass or more relative to the total mass of the polymerizable liquid crystal compounds contained in the polymerizable liquid crystal composition of the present invention. In one embodiment of the present invention, the polymerizable liquid crystal composition does not contain any polymerizable liquid crystal compound other than the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2).

The content of the polymerizable liquid crystal compound in the polymerizable liquid crystal composition of the present invention (the total amount of all polymerizable liquid crystal compounds) is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass, more preferably 85 to 98 parts by mass, and further preferably 90 to 95 parts by mass relative to 100 parts by mass of the solid components of the polymerizable liquid crystal composition. If the total mass of the polymerizable liquid crystal compound is within the above range, it is advantageous from the perspective of the orientation of the resulting liquid crystal cured film. Furthermore, in this specification, the polymerizable liquid crystal compound contains the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2), and when the polymerizable liquid crystal compound contains the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2), it contains other polymerizable liquid crystal compounds different from these (hereinafter collectively referred to as "polymerizable liquid crystal mixture"). The solid content of the polymerizable liquid crystal composition refers to all components after removing volatile components such as organic solvents from the polymerizable liquid crystal composition.

The polymerizable liquid crystal composition of the present invention may further contain additives such as an organic solvent, a photopolymerization initiator, a polymerization inhibitor, a photosensitizer, and a leveling agent in addition to the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2). These components may be used alone or in combination of two or more.

In the present invention, the polymerizable liquid crystal mixture is usually coated on a substrate or the like in a state of being dissolved in a solvent, so it is preferable to include a solvent. As the solvent, it is preferable to use a solvent that can dissolve polymerizable liquid crystal compounds such as the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2), and it is preferable to use a solvent that is inert to the polymerization reaction of the polymerizable liquid crystal compound. The polymerizable liquid crystal composition of the present invention can significantly improve the solvent solubility of the polymerizable liquid crystal compound (2) compared to the case where the polymerizable liquid crystal compound (2) is dissolved in a solvent alone by combining the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2). For this purpose, various solvents can be used. Examples of the solvent include: alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, 1-methoxy-2-propanol, 2-butoxyethanol, and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and methyl ethyl ketone. Ketone solvents such as methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane, and heptane; aliphatic hydrocarbon solvents such as ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; ether solvents such as tetrahydrofuran and dimethoxyethane; chlorine-containing solvents such as chloroform and chlorobenzene; amide solvents such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone (NMP), and 1,3-dimethyl-2-imidazolidinone. These solvents may be used alone or in combination of two or more. Among these, organic solvents are preferred, and alcohol solvents, ester solvents, ketone solvents, chlorine-containing solvents, amide solvents, and aromatic hydrocarbon solvents are more preferred. From the perspective of productivity, at least one selected from the group consisting of methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, and N-methylpyrrolidone is further preferred.

The solvent content in the polymerizable liquid crystal composition is preferably 50-98 parts by mass, more preferably 50-95 parts by mass, relative to 100 parts by mass of the polymerizable liquid crystal composition. Therefore, the solid content in 100 parts by mass of the polymerizable liquid crystal composition is preferably 2-50 parts by mass, more preferably 5-50 parts by mass. If the solid content is less than 50 parts by mass, the viscosity of the polymerizable liquid crystal composition decreases, resulting in a generally uniform film thickness and less prone to unevenness. The solid content can be appropriately determined based on the desired thickness of the liquid crystal cured film. The polymerizable liquid crystal composition of the present invention has excellent solubility in a solvent by comprising a polymerizable liquid crystal compound (1) and a polymerizable liquid crystal compound (2). Therefore, it is also advantageous in that the amount of organic solvent used during application and storage can be reduced.

The polymerizable liquid crystal composition of the present invention preferably includes a photopolymerization initiator. A photopolymerization initiator is a compound that generates reactive species upon exposure to light, thereby initiating the polymerization reaction of the polymerizable liquid crystal. Examples of reactive species include free radicals, cations, and anions. Among these, photopolymerization initiators that generate free radicals upon exposure to light are preferred due to their ease of reaction control. A single photopolymerization initiator may be used, or a combination of two or more may be used.

Examples of the photopolymerization initiator include benzoin compounds, benzophenone compounds, benzoyl ketal compounds, phenanthene compounds, acylphosphine oxide compounds, α-hydroxyketone compounds, α-aminoketone compounds, trisulphurium compounds, iodonium salts, and coronium salts. Specifically, Irgacure (Irgacure is a registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369, Irgacure 379, Irgacure 127, Irgacure 2959, Irgacure 754, Irgacure 379EG (all manufactured by BASF Japan Co., Ltd.), Seikuol BZ, Seikuol Z, Seikuol BEE (all manufactured by Seiko Chemical Co., Ltd.), Kayacure BP100 (manufactured by Nippon Kayaku Co., Ltd.), Kayacure UVI-6992 (manufactured by Dow Chemical Co., Ltd.), Adeka Optomer SP-152, Adeka Optomer SP-170, Adeka Optomer N-1717, Adeka Optomer N-1919, Adeka Arkles NCI-831, Adeka Arkles NCI-930 (all manufactured by ADEKA Co., Ltd.), TAZ-A, TAZ-PP (all manufactured by Nihon SiberHegner Co., Ltd.), and TAZ-104 (manufactured by Sanwa Chemical Co., Ltd.). In the present invention, the polymerizable liquid crystal mixed composition preferably contains at least one photopolymerization initiator, but may also contain two or more photopolymerization initiators.

In order to fully utilize the energy emitted by the light source and achieve excellent productivity, the maximum absorption wavelength of the photopolymerization initiator is preferably 300 nm to 400 nm, more preferably 300 nm to 380 nm. Among them, α-acetophenone-based polymerization initiators and oxime-based photopolymerization initiators are preferred.

Examples of the α-acetophenone compound include 2-methyl-2-thiophenyl-1-(4-methylthiophenyl)propane-1-one, 2-dimethylamino-1-(4-thiophenylphenyl)-2-benzylbutane-1-one, and 2-dimethylamino-1-(4-thiophenylphenyl)-2-(4-methylphenylmethyl)butane-1-one. More preferred examples include 2-methyl-2-thiophenyl-1-(4-methylthiophenyl)propane-1-one and 2-dimethylamino-1-(4-thiophenylphenyl)-2-benzylbutane-1-one. Examples of commercially available α-acetophenone compounds include Irgacure 369, 379EG, and 907 (all manufactured by BASF Japan Co., Ltd.) and Seikuol BEE (manufactured by Seiko Chemical Industries, Ltd.).

Oxime-based photopolymerization initiators generate methyl radicals upon exposure to light. These methyl radicals facilitate polymerization of the polymerizable liquid crystal compound deep within the formed liquid crystal cured film. Furthermore, from the perspective of more efficiently promoting polymerization deep within the formed liquid crystal cured film, it is preferable to use a photopolymerization initiator that can efficiently utilize ultraviolet light with a wavelength of 350 nm or longer. Preferred photopolymerization initiators that can efficiently utilize ultraviolet light with a wavelength of 350 nm or longer are trioxane compounds or oxime ester-type carbazole compounds. From the perspective of sensitivity, oxime ester-type carbazole compounds are more preferred. Examples of oxime ester carbazole compounds include 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyl oxime)], and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyl oxime). Commercially available oxime ester carbazole compounds include Irgacure OXE-01, Irgacure OXE-02, and Irgacure OXE-03 (all manufactured by BASF Japan Co., Ltd.), Adeka Optomer N-1919, and Adeka Arkles NCI-831 (all manufactured by ADEKA Co., Ltd.).

The amount of the photopolymerization initiator added is typically 0.1 to 30 parts by mass, preferably 0.5 to 20 parts by mass, and more preferably 1 to 15 parts by mass, relative to 100 parts by mass of the polymerizable liquid crystal compound. When the amount of the photopolymerization initiator is within this range, the reaction of the polymerizable groups proceeds sufficiently and the alignment of the polymerizable liquid crystal compound is not easily disturbed.

By using a sensitizer, the photopolymerization initiator can be made highly sensitive. Examples of photosensitizers include thiophene, 9-oxothiophene, Such as thiazolinone; anthracene and alkyl ethers with substituents; phenanthrene; rubrophene. As photosensitizers, for example, thiazolinone, 9-oxothiophene The content of the photosensitizer is typically 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, and even more preferably 0.1 to 3 parts by weight, relative to 100 parts by weight of the total polymerizable liquid crystal compound.

The polymerization reaction of the polymerizable liquid crystal compound can be controlled by preparing a polymerization inhibitor. Examples of the polymerization inhibitor include: hydroquinones having substituents such as hydroquinone and alkyl ethers; o-catechols having substituents such as alkyl ethers such as butyl o-catechol; radical scavengers such as o-catechols and 2,2,6,6-tetramethyl-1-piperidinyloxy free radicals; thiophenols; β-naphthylamines and β-naphthols. In order to polymerize the polymerizable liquid crystal compound (1) without disturbing the alignment, the content of the polymerization inhibitor is generally 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, and further preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable liquid crystal compound.

Furthermore, the polymerizable liquid crystal composition of the present invention may include a leveling agent. A leveling agent is an additive that adjusts the fluidity of the polymerizable liquid crystal composition, thereby making the resulting film smoother. Examples of such leveling agents include silicone-based, polyacrylate-based, and perfluoroalkyl ester-based leveling agents. Specific examples include DC3PA, SH7PA, DC11PA, SH28PA, SH29PA, SH30PA, ST80PA, ST86PA, SH8400, SH8700, and FZ2123 (all manufactured by Toray Dow Corning Co., Ltd.), KP321, KP323, KP324, KP326, KP340, KP341, X22-161A, and KF6001 (all manufactured by Shin-Etsu Chemical Co., Ltd.), TSF400, TSF401, TSF410, TSF4300, TSF4440, TSF4445, TSF-4446, TSF4452, and TSF4460 (all manufactured by Maitu Advanced Materials Japan Co., Ltd.), and fluorinert (fluorinert is a registered trademark). FC-72, fluorinert FC-40, fluorinert FC-43, fluorinert FC-3283 (all manufactured by Sumitomo 3M Co., Ltd.), MEGAFAC (registered trademark) R-08, MEGAFAC R-30, MEGAFAC R-90, MEGAFAC F-410, MEGAFAC F-411, MEGAFAC F-443, MEGAFAC F-445, MEGAFAC F-470, MEGAFAC F-477, MEGAFAC F-479, MEGAFAC F-482, MEGAFAC F-483 (all manufactured by DIC Co., Ltd.), Eftop (trade name) EF301, Eftop EF303, Eftop EF351, Eftop EF352 (all manufactured by Mitsubishi Materials Corporation), Surflon (registered trademark) S-381, Surflon S-382, Surflon S-383, Surflon S-393, Surflon SC-101, Surflon SC-105, KH-40, SA-100 (all manufactured by AGC Seimi Chemical Co., Ltd.), E1830, E5844 (manufactured by Daikin Fine Chemicals Laboratories), BM-1000, BM-1100, BYK-352, BYK-353, and BYK-361N (trade names, all manufactured by BM Chemie Co., Ltd.). Among these, polyacrylate-based leveling agents and perfluoroalkyl ester-based leveling agents are preferred.

The leveling agent content in the polymerizable liquid crystal composition is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, relative to 100 parts by mass of the total polymerizable liquid crystal compound. A leveling agent content within this range is preferred because it facilitates alignment of the polymerizable liquid crystal compound and tends to produce a smoother cured liquid crystal film. The polymerizable liquid crystal composition may contain two or more leveling agents.

The polymerizable liquid crystal composition of the present invention can be prepared by adding additives such as a solvent, a photopolymerization initiator, a polymerization inhibitor, a photosensitizer or a leveling agent to the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) as needed, and stirring and mixing the mixture at a specific temperature.

<Phase Difference Film> The polymerizable liquid crystal composition of the present invention, due to its low phase transition temperature, allows the production of liquid crystal cured films at lower processing temperatures, minimizing the effects of heating and resulting in liquid crystal cured films with excellent optical properties. Furthermore, due to its high solubility in solvents, it exhibits excellent coating and film-forming properties, thereby suppressing the occurrence of alignment defects caused by undissolved polymerizable liquid crystal compounds, precipitates, and other deposits within the composition. Consequently, the use of the polymerizable liquid crystal composition of the present invention allows for film formation without compromising the inherent optical properties of the polymerizable liquid crystal compounds, resulting in liquid crystal cured films with excellent optical properties. Therefore, the present invention also relates to a cured product of the polymerizable liquid crystal composition of the present invention, and in particular to a phase difference film, which is a cured product of the polymerizable liquid crystal composition, comprising a liquid crystal cured film formed by curing the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in the polymerizable liquid crystal composition in an aligned state. The phase difference film comprising the above-mentioned liquid crystal cured film can fully exhibit the optical properties that the polymerizable liquid crystal compound used can originally exhibit, and can become a phase difference film with higher optical performance.

The liquid crystal cured film constituting the phase difference film of the present invention may include a homopolymer of the polymerizable liquid crystal compound (1) and a homopolymer of the polymerizable liquid crystal compound (2) in an aligned state, or may include a copolymer of a mixture of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in an aligned state. In view of the ease of polymerization and the ease of obtaining a uniform liquid crystal cured film, the liquid crystal cured film constituting the phase difference film of the present invention is preferably a copolymer of a mixture of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) in an aligned state.

In one embodiment of the present invention, the retardation film of the present invention is a cured product of the polymerizable liquid crystal composition of the present invention, comprising a liquid crystal cured film having the optical properties represented by the following formulas (i), (ii), and (iii). The liquid crystal cured film is typically cured while the polymerizable liquid crystal compound is aligned horizontally relative to the plane of the liquid crystal cured film (hereinafter also referred to as a "horizontally aligned liquid crystal cured film"). Re(450)/Re(550)≦1.00          (i) 1.00≦Re(650)/Re(550)          (ii) 100 nm≦Re(550)≦180 nm    (iii) [Wherein, Re(λ) represents the in-plane phase difference value of the liquid crystal cured film at a wavelength of λ nm, Re＝(nx(λ)－ny(λ))×d (d represents the thickness of the liquid crystal cured film, nx represents the principal refractive index at a wavelength of λ nm in a direction parallel to the plane of the liquid crystal cured film in the refractive index ellipse formed by the liquid crystal cured film, ny represents the refractive index at a wavelength of λ nm in a direction parallel to the plane of the liquid crystal cured film and orthogonal to the direction of nx in the refractive index ellipse formed by the liquid crystal cured film)]

When the horizontally aligned liquid crystal cured film satisfies equations (i) and (ii), the horizontally aligned liquid crystal cured film exhibits a so-called reverse wavelength dispersion property, in which the in-plane phase difference value at short wavelengths is smaller than the in-plane phase difference value at long wavelengths. In order to improve the reverse wavelength dispersion property and further improve the optical properties of the phase difference film, Re(450)/Re(550) is preferably 0.70 or more, more preferably 0.78 or more, more preferably 0.90 or less, more preferably 0.88 or less, further preferably 0.86 or less, particularly preferably 0.85 or less, and most preferably 0.84 or less. Furthermore, Re(650)/Re(550) is preferably 1.00 or more, more preferably 1.01 or more, and further preferably 1.02 or more.

The above-mentioned in-plane retardation value can be adjusted by the thickness d of the horizontally aligned liquid crystal cured film. Since the in-plane retardation value is determined by the above formula Re(λ) = (nx(λ) - ny(λ)) × d, in order to obtain the desired in-plane retardation value (Re(λ): the in-plane retardation value of the horizontally aligned liquid crystal cured film at wavelength λ (nm), the three-dimensional refractive index and film thickness d can be adjusted.

Furthermore, when a horizontally aligned liquid crystal cured film satisfies formula (iii), an elliptically polarizing plate having a retardation film including the horizontally aligned liquid crystal cured film is used in an organic EL (electroluminescence) display device, the front-reflected hue is significantly improved (coloration is suppressed). The in-plane retardation value preferably falls within a range of 120 nm ≤ Re(550) ≤ 170 nm, and further preferably falls within a range of 130 nm ≤ Re(550) ≤ 150 nm.

In one embodiment of the present invention, the retardation film of the present invention is a cured product of the polymerizable liquid crystal composition of the present invention, comprising a liquid crystal cured film having the optical properties represented by the following formulas (iv), (v), and (vi). The liquid crystal cured film is typically cured while the polymerizable liquid crystal compound is aligned perpendicularly to the plane of the liquid crystal cured film (hereinafter also referred to as a "vertically aligned liquid crystal cured film"). Rth(450)/Rth(550)≦1.00         (iv) 1.00≦Rth(650)/Rth(550)         (v) -100 nm≦Rth(550)≦-40 nm    (vi) [Wherein, Rth(λ) represents the phase difference in the thickness direction of the liquid crystal cured film at a wavelength of λ nm, Rth＝((nx(λ)＋ny(λ))/2－nz)×d(d represents the thickness of the liquid crystal cured film, nx represents the principal refractive index at a wavelength of λ nm in the direction parallel to the plane of the liquid crystal cured film in the refractive index ellipse formed by the liquid crystal cured film, ny represents the wavelength of λ in the direction parallel to the plane of the liquid crystal cured film and orthogonal to the direction of nx in the refractive index ellipse formed by the liquid crystal cured film (nz represents the refractive index at wavelength λ nm in the refractive index ellipse formed by the liquid crystal cured film in the direction perpendicular to the plane of the liquid crystal cured film)

When the vertically aligned liquid crystal curing film satisfies formulas (iv) and (v), in an elliptical polarizing plate having a phase difference film including the vertically aligned liquid crystal curing film, the reduction in ellipticity can be suppressed on the short wavelength side, and the oblique phase reflection hue can be improved. The value of Rth(450)/Rth(550) of the vertically aligned liquid crystal curing film is preferably 0.70 or more, more preferably 0.78 or more, more preferably 0.90 or less, more preferably 0.88 or less, further preferably 0.86 or less, particularly preferably 0.85 or less, and most preferably 0.84 or less. Furthermore, Rth(650)/Rth(550) is preferably 1.0 or more, more preferably 1.01 or more, and further preferably 1.02 or more.

Furthermore, when the vertically aligned liquid crystal cured film satisfies formula (vi), the oblique reflection hue can be improved when an elliptically polarizing plate having a retardation film including the vertically aligned liquid crystal cured film is used in an organic EL display device. The retardation value Rth(550) in the thickness direction of the vertically aligned liquid crystal cured film is preferably not less than -90 nm, more preferably not less than -80 nm, and even more preferably not more than -50 nm.

The retardation film of the present invention can be produced, for example, by a method comprising the following steps: Forming a coating film of the polymerizable liquid crystal composition of the present invention, drying the coating film, and aligning the polymerizable liquid crystal compound in the polymerizable liquid crystal composition; And, While maintaining the alignment, polymerizing the polymerizable liquid crystal compound by irradiation with light to form a liquid crystal cured film.

A film of a polymerizable liquid crystal composition can be formed by coating the polymerizable liquid crystal composition on a substrate or an alignment film described below. Substrates include glass substrates and film substrates. From the perspective of processability, resin film substrates are preferred. Examples of resins constituting the film substrate include polyolefins such as polyethylene, polypropylene, and northene polymers; cyclic olefin resins; polyvinyl alcohol; polyethylene terephthalate; polymethacrylate; polyacrylate; cellulose esters such as triacetyl cellulose, diacetyl cellulose, and cellulose acetate propionate; polyethylene naphthalate; polycarbonate; polysulfone; polyethersulfone; polyetherketone; and plastics such as polyphenylene sulfide and polyphenylene ether. This resin can be formed into a film to form a substrate using known methods such as solvent casting and melt extrusion. The substrate surface may have a protective layer formed from acrylic resin, methacrylic resin, epoxy resin, cyclobutane resin, polyurethane resin, melamine resin, etc., and may also be subjected to surface treatments such as silicone treatment, plasma treatment, corona treatment, and plasma treatment.

Commercially available products can be used as the substrate. Examples of commercially available cellulose ester substrates include those manufactured by Fujitac Film Co., Ltd., and those manufactured by Konica Minolta Opto Co., Ltd., such as "KC8UX2M," "KC8UY," and "KC4UY." Examples of commercially available cyclic olefin resins include "Topas (registered trademark)" and other cyclic olefin resins manufactured by Ticona Corporation (solely owned); "ARTON (registered trademark)" and other cyclic olefin resins manufactured by JSR Corporation; "ZEONOR (ZEONOR is a registered trademark)" and "ZEONEX (ZEONEX is a registered trademark)" and other cyclic olefin resins manufactured by Zeon Co., Ltd.; and "APEL (registered trademark)" and other cyclic olefin resins manufactured by Mitsui Chemicals, Inc. Commercially available cyclic olefin resin substrates may also be used. Examples of commercially available cyclic olefin resin substrates include: "S-SINA (registered trademark)" and "SCA40 (registered trademark)" manufactured by Sekisui Chemical Industries, Ltd.; "ZEONOR Film (registered trademark)" manufactured by Optes Co., Ltd.; and "ARTON Film (registered trademark)" manufactured by JSR Co., Ltd.

From the perspectives of thinning the retardation film, ease of substrate peeling, and substrate handling, the thickness of the substrate is generally 5 to 300 μm, preferably 10 to 150 μm.

Examples of methods for coating the polymerizable liquid crystal composition on a substrate include known methods such as spin coating, extrusion, gravure coating, die coating, rod coating, and smear coating, and printing methods such as flexographic coating.

Next, the solvent is removed by drying, etc., thereby forming a dry coating. Examples of drying methods include natural drying, ventilation drying, heat drying, and reduced pressure drying. In this case, the coating obtained from the polymerizable liquid crystal composition can be heated to dry out the solvent from the coating, and the polymerizable liquid crystal compound can be aligned in a desired direction (e.g., horizontal or vertical) relative to the plane of the coating. The heating temperature of the coating can be appropriately determined by considering the polymerizable liquid crystal compound used and the material of the substrate forming the coating. In order to cause the polymerizable liquid crystal compound to transition to a liquid crystal phase, a temperature above the liquid crystal phase transition temperature is generally required. In order to remove the solvent contained in the polymerizable liquid crystal composition and make the polymerizable liquid crystal compound into the desired alignment state, for example, the polymerizable liquid crystal composition can be heated to a temperature above the liquid crystal phase transition temperature (smectic phase transition temperature or nematic phase transition temperature) of the polymerizable liquid crystal compound contained in the above-mentioned polymerizable liquid crystal composition.

The polymerizable liquid crystal composition of the present invention comprises a polymerizable liquid crystal compound (1) and a polymerizable liquid crystal compound (2), and can generally undergo liquid crystal phase transition at a temperature lower than the temperature at which the individual polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) transition to the liquid crystal phase. In one embodiment of the present invention, the solid-liquid crystal phase transition temperature of the polymerizable liquid crystal mixture constituting the polymerizable liquid crystal composition of the present invention is preferably above 25°C and below 153°C. If the temperature at which the phase transition to the liquid crystal phase occurs is within the above range, a liquid crystal cured film can be produced at a lower processing temperature, which can suppress the reduction in optical properties caused by heating, and obtain a liquid crystal cured film having higher optical properties that the polymerizable liquid crystal compound can originally exhibit. In addition, in the production of a phase difference film using the polymerizable liquid crystal composition of the present invention, excessive consumption of heat energy can be suppressed, which can improve production efficiency. Furthermore, since the liquid crystal phase transition can occur by heating at relatively low temperatures, it also offers the advantage of a wide range of support substrate options for coating the polymerizable liquid crystal composition. In the present invention, the solid-liquid crystal phase transition temperature of the polymerizable liquid crystal mixture is typically 40°C or higher, preferably 50°C or higher, and even more preferably 60°C or higher, so that the resulting liquid crystal cured film exhibits inverse wavelength dispersion properties. Furthermore, to achieve more significant effects of the present invention, it is more preferably 150°C or lower, even more preferably 145°C or lower, and particularly preferably 144°C or lower. The liquid crystal phase transition temperature can be measured, for example, using a polarizing microscope equipped with a temperature control stage, a differential scanning calorimeter (DSC), or a thermogravimetric differential thermal analyzer (TG-DTA). The phase transition temperature of the polymerizable liquid crystal mixture of the present invention, which contains at least two polymerizable liquid crystal compounds, refers to the temperature measured using a mixture of the polymerizable liquid crystal compounds, wherein all the polymerizable liquid crystal compounds constituting the polymerizable liquid crystal mixture are mixed in the same ratio as the composition of the polymerizable liquid crystal mixture.

The heating time can be appropriately determined based on the heating temperature, the type of polymerizable liquid crystal compound used, the type or boiling point of the solvent, and its amount, and is generally 15 seconds to 10 minutes, preferably 0.5 to 5 minutes.

Removal of the solvent from the coating can be performed simultaneously with heating to a temperature above the liquid crystal phase transition temperature of the polymerizable liquid crystal compound, or separately. From the perspective of improving productivity, simultaneous removal is preferred. Prior to heating to a temperature above the liquid crystal phase transition temperature of the polymerizable liquid crystal compound, a pre-drying step can be performed to appropriately remove the solvent from the coating without polymerizing the polymerizable liquid crystal compound contained in the coating obtained from the polymerizable liquid crystal composition. Examples of drying methods in this pre-drying step include natural drying, ventilation drying, heating drying, and reduced pressure drying. The drying temperature (heating temperature) in this drying step can be appropriately determined based on the type of polymerizable liquid crystal compound used, the type of solvent, its boiling point, and its amount.

Next, while maintaining the alignment of the polymerizable liquid crystal compound in the resulting dry coating, the polymerizable liquid crystal compound is polymerized by irradiation with light, thereby forming a polymer of the polymerizable liquid crystal compound in the desired alignment, i.e., a liquid crystal cured film. The polymerizable liquid crystal composition of the present invention can suppress damage to the polymerizable liquid crystal compound while being highly polymerized by irradiation with high-intensity light such as ultraviolet light. Therefore, photopolymerization is generally used as the polymerization method. In photopolymerization, the light irradiated on the dry coating is appropriately selected based on the type of polymerization initiator, the type of polymerizable liquid crystal compound contained in the dry coating, and its amount. Specific examples include one or more light selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays, and γ-rays, or an active electron beam. Among them, ultraviolet light is preferred because it is easy to control the progress of the polymerization reaction or because it can be used as a photopolymerization device by a wide range of users in this field. It is preferred to select the type of polymerizable liquid crystal compound or polymerization initiator contained in the polymerizable liquid crystal composition in a manner that can be photopolymerized by ultraviolet light. In addition, during polymerization, the polymerization temperature can be controlled by cooling the dried coating using an appropriate cooling method while irradiating the film with light. If the polymerization of the polymerizable liquid crystal compound is carried out at a lower temperature by adopting this cooling method, a liquid crystal cured film can be properly formed even if the substrate used has relatively low heat resistance. In addition, the polymerization reaction can be promoted by raising the polymerization temperature within a range that does not cause defects caused by heat during light irradiation (such as deformation of the substrate caused by heat). During photopolymerization, a patterned cured film can be obtained by masking or developing.

Examples of light sources for the active energy rays include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, halogen lamps, carbon arc lamps, tungsten filament lamps, gallium lamps, excimer lasers, LED (Light Emitting Diode) light sources emitting light in the wavelength range of 380 to 440 nm, chemical lamps, black light lamps, microwave-excited mercury lamps, and metal halide lamps.

The UV irradiation intensity is typically 10 to 3,000 mW/ ^cm² . The UV irradiation intensity is preferably within the wavelength range effective for activating photopolymerization initiators. The irradiation duration is typically 0.1 second to 10 minutes, preferably 0.1 second to 5 minutes, more preferably 0.1 second to 3 minutes, and even more preferably 0.1 second to 1 minute. If irradiated once or multiple times at this UV irradiation intensity, the cumulative amount of light is 10 to 3,000 mJ/ ^cm² , preferably 50 to 2,000 mJ/ ^cm² , and even more preferably 100 to 1,000 mJ/ ^cm² .

The thickness of the liquid crystal cured film can be appropriately selected according to the display device used, preferably 0.2 to 3 μm, more preferably 0.2 to 2 μm.

A coating of a polymerizable liquid crystal composition can be formed on an alignment film. An alignment film possesses a force that regulates the alignment of the polymerizable liquid crystal compound in a desired direction. For example, there are horizontal alignment films that regulate the alignment of the polymerizable liquid crystal compound in a horizontal direction, and vertical alignment films that regulate the alignment of the polymerizable liquid crystal compound in a vertical direction. The alignment regulating force can be adjusted by varying the type of alignment film, its surface condition, and friction conditions. For alignment films made of photoalignable polymers, this can be adjusted by varying polarized light irradiation conditions.

Alignment films are preferably solvent-resistant, preventing dissolution during coating of the polymerizable liquid crystal composition, and heat-resistant during heat treatments used for solvent removal or alignment of the polymerizable liquid crystal compound described below. Examples of alignment films include those containing an aligning polymer, photo-alignment films, trench-alignment films with a concave-convex pattern or multiple grooves on the surface, and stretched films extending in the alignment direction. Photo-alignment films are preferred for their accuracy and quality in terms of alignment angle.

Examples of aligning polymers include polyamides or gelatins having amide bonds within their molecules, polyimides having imide bonds within their molecules and their hydrolyzates, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyazole, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid, and polyacrylates. Among these, polyvinyl alcohol is preferred. Aligning polymers may be used alone or in combination of two or more.

An alignment film comprising an alignment polymer is typically obtained by applying a composition obtained by dissolving the alignment polymer in a solvent (hereinafter sometimes referred to as an "alignment polymer composition") to a substrate and removing the solvent, or by applying the alignment polymer composition to a substrate, removing the solvent, and then rubbing the composition (rubbing method). Examples of the solvent include those previously exemplified as solvents that can be used in polymerizable liquid crystal compositions.

The concentration of the alignment polymer in the alignment polymer composition can be such that the alignment polymer material can be completely dissolved in the solvent. When converted to solid content of the solution, the concentration is preferably 0.1-20%, more preferably 0.1-10%.

As the alignment polymer composition, a commercially available alignment film material can be used directly. Examples of commercially available alignment film materials include Sunever (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optomer (registered trademark, manufactured by JSR Corporation).

Examples of the method for coating the aligning polymer composition on the substrate include the same methods as those exemplified for the method for coating the polymerizable liquid crystal composition on the substrate.

Examples of methods for removing the solvent contained in the alignment polymer composition include natural drying, ventilation drying, heat drying, and reduced pressure drying.

To impart alignment-controlling forces to the alignment film, a rubbing treatment (rubbing method) can be performed as needed. One example of a rubbing method for imparting alignment-controlling forces is to contact a rotating rubbing roller wrapped with a rubbing cloth, with the alignment polymer film formed on the substrate surface by coating and annealing the aligning polymer composition. By masking during the rubbing treatment, multiple regions (patterns) with different alignment directions can be formed on the alignment film.

Photo-alignment films are typically produced by applying a composition containing a polymer or monomer with photoreactive groups and a solvent (hereinafter referred to as the "photo-alignment film-forming composition") to a substrate, removing the solvent, and then irradiating the substrate with polarized light (preferably polarized ultraviolet (UV)). Photo-alignment films are also advantageous in that the direction of the alignment-controlling force can be arbitrarily controlled by selecting the polarization direction of the irradiated light.

Photoreactive groups are groups that induce liquid crystal alignment upon exposure to light. Specifically, they include groups that participate in photoreactions that are the source of liquid crystal alignment. These photoreactions include molecular alignment induction, isomerization, dimerization, photocrosslinking, or photodecomposition reactions upon exposure to light. Groups that participate in dimerization or photocrosslinking are preferred due to their superior alignment properties. The photoreactive group is preferably a group having an unsaturated bond, especially a double bond, and more preferably a group having at least one selected from the group consisting of a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond (N=N bond), and a carbon-oxygen double bond (C=O bond).

Examples of photoreactive groups having a C=C bond include a vinyl group, a polyenyl group, a stilbene group, a stilbazole group, a stilbazolium group, a chalcone group, and a cinnamyl group. Examples of photoreactive groups having a C=N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. Examples of photoreactive groups having an N=N bond include azophenyl groups, azonaphthyl groups, aromatic heterocyclic azo groups, bisazo groups, formyl groups, and groups having an oxyazobenzene structure. Examples of photoreactive groups having a C=O bond include a benzophenone group, a coumarin group, anthraquinone group, and a maleimido group. These groups may have a substituent such as an alkyl group, an alkoxy group, an aryl group, an allyloxy group, a cyano group, an alkoxycarbonyl group, a hydroxyl group, a sulfonic acid group, or a halogenated alkyl group.

Among these, photoreactive groups that participate in photodimerization are preferred. Cinnamyl and chalcone groups are particularly preferred, as they facilitate obtaining photoalignment films with relatively low polarized light exposure and excellent thermal and temporal stability. Polymers containing photoreactive groups are particularly preferred, with cinnamyl groups at the end of the polymer side chains forming a cinnamic acid structure.

By applying the photo-alignment film-forming composition onto a substrate, a photo-alignment-inducing layer can be formed on the substrate. Examples of solvents included in this composition include those previously exemplified as solvents for polymerizable liquid crystal compositions, and can be appropriately selected based on the solubility of the polymer or monomer having a photoreactive group.

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

Methods for applying the photo-alignment film-forming composition to a substrate include the same methods as those for applying the aligning polymer composition to a substrate. Methods for removing the solvent from the applied photo-alignment film-forming composition include, for example, natural drying, air drying, heat drying, and reduced pressure drying.

Irradiation with polarized light can be performed by directly irradiating the composition for forming a photo-alignment film coated on the substrate after removing the solvent, or by irradiating the composition from the substrate side, where the polarized light is transmitted. The polarized light is preferably substantially parallel. The wavelength of the irradiated polarized light can be within the wavelength range where the photoreactive groups of the polymer or monomer containing the photoreactive groups can absorb light energy. Specifically, ultraviolet light (UV) with a wavelength of 250 to 400 nm is particularly preferred. Examples of light sources used for polarized light irradiation include xenon lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, and ultraviolet lasers such as KrF and ArF. High-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are particularly preferred. High-pressure mercury lamps, ultra-high-pressure mercury lamps, and metal halide lamps are particularly preferred due to their high intensity of ultraviolet light at a wavelength of 313 nm. Polarized UV irradiation can be achieved by passing light from these light sources through an appropriate polarizing element. As the polarizing element, a polarizing prism such as a polarizer, a Glan-Thompson prism, or a Glan-Taylor prism, or a wire-grid type polarizing element can be used.

Furthermore, if masking is performed during rubbing or polarized light irradiation, multiple regions (patterns) with different liquid crystal alignment directions can also be formed.

Groove alignment films have a concave-convex pattern or multiple grooves on their surface. When a polymerizable liquid crystal compound is applied to a film with multiple equally spaced linear grooves, the liquid crystal molecules align along the grooves.

Methods for obtaining a groove-aligned film include, for example, a method of forming a concave-convex pattern by exposing the surface of a photosensitive polyimide film through an exposure mask having slits in the shape of the pattern, followed by development and rinsing; a method of forming a layer of uncured UV-curable resin on a plate-shaped master having grooves on its surface, transferring the formed resin layer to a substrate, and then curing the layer; and a method of forming a concave-convex pattern by pressing a roll-shaped master having a plurality of grooves against a film of uncured UV-curable resin formed on a substrate, followed by curing the layer.

Furthermore, as a material that exhibits an alignment restraining force that aligns the polymerizable liquid crystal compound in a direction perpendicular to the plane of the liquid crystal cured film, in addition to the above-mentioned alignment polymers, fluorine-based polymers such as perfluoroalkyl esters and silane compounds, as well as polysiloxane compounds obtained by condensation reactions thereof, can be used.

When a silane compound is used as a material for forming an alignment film, from the perspective of easily reducing surface tension and easily improving adhesion with the adjacent layer of the alignment film, a compound whose constituent elements include Si and C is preferred, and a silane compound can be used well. As the silane compound, an ionic compound containing silane can be used, and by using such a silane compound, the vertical alignment limiting force can be improved. As the silane compound, one type can be used alone, two or more types can be used in combination, or it can be mixed with other materials. In the case where the silane compound is a non-ionic silane compound, from the perspective of easily improving the vertical alignment limiting force, a silane compound having an alkyl group at the molecular end is preferred, and a silane compound having an alkyl group with 3 to 30 carbon atoms is more preferred.

The thickness of the alignment film (including an alignment film of an alignment polymer or a photo-alignment film) is generally in the range of 10 to 10,000 nm, preferably in the range of 10 to 1,000 nm, more preferably in the range of 10 to 500 nm, further preferably in the range of 10 to 300 nm, and particularly preferably in the range of 50 to 250 nm.

The present invention includes a polarizing plate (elliptical polarizing plate) comprising the retardation film of the present invention. The polarizing plate of the present invention typically comprises the retardation film of the present invention and a polarizing film. A polarizing film is a film having a polarizing function. Examples include a stretched film adsorbed with a dye having anisotropic absorption, or a film coated with a dye having anisotropic absorption, as a polarizing element. Examples of dyes having anisotropic absorption include dichroic dyes.

A film comprising a stretched film adsorbed with a dye having absorption anisotropy as a polarizing element is typically produced by sandwiching a transparent protective film, via an adhesive, between at least one side of a polarizing element produced by the following steps: uniaxially stretching a polyvinyl alcohol-based resin film; dyeing the polyvinyl alcohol-based resin film with a dichroic dye to adsorb the dichroic dye; treating the polyvinyl alcohol-based resin film adsorbed with the dichroic dye with an aqueous boric acid solution; and, after the treatment with the aqueous boric acid solution, washing with water.

Polyvinyl alcohol resins are obtained by saponifying polyvinyl acetate resins. Polyvinyl acetate resins include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, alkenes, vinyl ethers, unsaturated sulfonic acids, and acrylamides containing ammonium groups.

The saponification degree of polyvinyl alcohol resins is typically around 85-100 mol%, preferably 98 mol% or higher. Polyvinyl alcohol resins can be modified, for example, polyvinyl formal or polyvinyl acetaldehyde modified with aldehydes can also be used. The degree of polymerization of polyvinyl alcohol resins is typically around 1,000-10,000, preferably 1,500-5,000.

The resulting film of this polyvinyl alcohol-based resin is used as a precursor for a polarizing film. The method for forming the polyvinyl alcohol-based resin film is not particularly limited and can be formed using a known method. The thickness of the polyvinyl alcohol-based precursor film can be, for example, approximately 10 to 150 μm.

The uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before dyeing with a dichroic dye, simultaneously with dyeing with a dichroic dye, or after dyeing with a dichroic dye. When uniaxial stretching is performed after dyeing, it can be performed before or during boric acid treatment. Alternatively, uniaxial stretching can be performed in multiple stages. Uniaxial stretching can be performed between rollers with different circumferential speeds or using heated rollers. Uniaxial stretching can be performed dry in the open air or wet in a state where the polyvinyl alcohol-based resin film is swollen using a solvent. The stretching ratio is usually around 3 to 8 times.

The polyvinyl alcohol-based resin film is dyed with a dichroic dye by, for example, immersing the polyvinyl alcohol-based resin film in an aqueous solution containing the dichroic dye.

Specifically, iodine or a dichroic organic dye is used as the dichroic dye. Examples of dichroic organic dyes include dichroic direct dyes containing bisazo compounds such as C.I. DIRECT RED 39, and dichroic direct dyes containing trisazo and tetrakisazo compounds. The polyvinyl alcohol-based resin film is preferably immersed in water before dyeing.

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

On the other hand, when using a dichroic organic dye as the dichroic pigment, a method is generally adopted in which a polyvinyl alcohol-based resin film is immersed in an aqueous solution containing a water-soluble dichroic dye to perform dyeing. The content of the dichroic organic dye in the aqueous solution is generally about 1× ^10-4 to 10 parts by mass, preferably 1× ^10-3 to 1 part by mass, and further preferably 1× ^10-3 to 1× ^10-2 parts by mass, relative to 100 parts by mass of water. The aqueous solution may contain an inorganic salt such as sodium sulfate as a dyeing auxiliary. The temperature of the dichroic dye aqueous solution used for dyeing is generally about 20 to 80°C. In addition, the immersion time in the aqueous solution (dyeing time) is generally about 10 to 1,800 seconds.

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

After the boric acid treatment, the polyvinyl alcohol-based resin film is typically washed with water. This washing process can be performed, for example, by immersing the boric acid-treated polyvinyl alcohol-based resin film in water. The water temperature during the washing process is typically between 5 and 40°C. The immersion time is typically between 1 and 120 seconds.

After washing, a drying treatment is performed to obtain a polarizing element. The drying treatment can be performed using, for example, a hot air dryer or a far-infrared heater. The temperature of the drying treatment is generally around 30-100°C, preferably 50-80°C. The time of the drying treatment is generally around 60-600 seconds, preferably 120-600 seconds. Through the drying treatment, the moisture content of the polarizing element is reduced to a practical level. The moisture content is generally around 5-20% by mass, preferably 8-15% by mass. If the moisture content is within the above range, it is easy to obtain a polarizing element with moderate flexibility and excellent thermal stability.

The thickness of the polarizing element obtained by uniaxially stretching the polyvinyl alcohol-based resin film, dyeing it with a dichroic dye, treating it with boric acid, washing it with water, and drying it is preferably 5 to 40 μm.

Examples of films coated with a dye having absorption anisotropy include films coated with a composition containing a dichroic dye having liquid crystal properties, or a composition containing a dichroic dye and polymerizable liquid crystals. Preferably, the film has a protective film on one or both sides. Examples of such protective films include the same resin films previously exemplified as substrates useful for producing liquid crystal cured films.

The film coated with anisotropic absorption dye is preferably thinner, but if it is too thin, the strength will decrease and the processability will be poor. The thickness of the film is usually 20 μm or less, preferably 5 μm or less, and more preferably 0.5-3 μm.

Specific examples of the film coated with a dye having absorption anisotropy include films described in Japanese Patent Application Laid-Open No. 2012-33249 and the like.

A transparent protective film can be laminated onto at least one side of the polarizing element obtained in this manner via an adhesive. The same transparent film as the resin film previously exemplified as a substrate for producing a liquid crystal cured film can be preferably used as the transparent protective film.

The polarizing plate of the present invention includes the phase difference film and the polarizing film of the present invention. For example, the phase difference film and the polarizing film of the present invention can be laminated via a bonding agent layer or an adhesive layer to obtain the elliptical polarizing plate of the present invention.

In one embodiment of the present invention, when laminating the retardation film of the present invention including a horizontally aligned liquid crystal cured film and a polarizing film, it is preferred that the lamination be performed such that the angle formed by the retardation axis (optical axis) of the horizontally aligned liquid crystal cured film constituting the retardation film and the absorption axis of the polarizing film reaches 45±5°.

The polarizing plate of the present invention can have the same structure as conventional elliptical polarizing plates, polarizing films, and retardation films. Examples of such structures include adhesive layers (sheets) used to attach elliptical polarizing plates to display devices such as organic EL, and protective films used to prevent damage or contamination to the surfaces of polarizing films or retardation films.

The polarizing plate of the present invention can be used in various display devices, particularly optical displays. A display device is a device having a display element, including a light-emitting element or light-emitting device as a light source. Examples of such display devices include liquid crystal displays, organic electroluminescent (EL) displays, inorganic electroluminescent (EL) displays, touch panel displays, electroluminescent displays (e.g., field emission displays (FEDs) and surface field emission displays (SEDs)), electronic paper (displays using electronic ink or electrophoretic elements), plasma displays, projection displays (e.g., grating valve imaging (GLV) displays and displays using digital micromirror devices (DMDs)), and piezoelectric ceramic displays. Liquid crystal display devices also include any of transmissive liquid crystal display devices, semi-transmissive liquid crystal display devices, reflective liquid crystal display devices, direct-view liquid crystal display devices, and projection liquid crystal display devices. These display devices can be display devices that display two-dimensional images or stereoscopic display devices that display three-dimensional images. In particular, the elliptical polarizing plate of the present invention can be well used in organic electroluminescent (EL) display devices and inorganic electroluminescent (EL) display devices. These display devices (optical displays) can exhibit excellent image display characteristics by using the polarizing plate of the present invention, which has excellent optical properties. [Examples]

Hereinafter, the present invention will be described in more detail by way of examples. Furthermore, "%" and "parts" in the examples refer to mass % and mass parts, respectively, unless otherwise specified.

[HPLC (high performance liquid chromatography) measurement] HPLC measurement can be performed under any conditions as long as the peaks derived from the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) can be separated. An example of HPLC measurement conditions is shown below. (Measurement Conditions) Analysis Apparatus: HPLC LC-10AT (Shimadzu Corporation) Column: L-Column ODS (ID 3.0 mm, Length 150 mm, Particle Size 3 μm) Temperature: 40°C Mobile Phase A: 0.1% (v/v)-TFA (Trifluoroacetic acid)/Water Mobile Phase B: 0.1% (v/v)-TFA/Acetonitrile Gradient: 0 min 70%-B 30 min 100%-B 60 min 100%-B 60.01 min 70%-B 75 min 70%-B Flow Rate: 0.5 mL/min Injection Volume: 5 μL Detection Wavelength: 254 nm

<Preparation of polymerizable liquid crystal compound> Synthesis Example 1: Preparation of polymerizable liquid crystal compound (2) According to the following process, a polymerizable liquid crystal compound represented by the following formula (2-1-1) (hereinafter referred to as "polymerizable liquid crystal compound (2-1-1)") was synthesized. [Chemical Example 42]

A 100 mL four-necked flask equipped with a Dai condenser and a thermometer was placed in a nitrogen atmosphere. 11.02 g of the compound (E-1) synthesized in the reference patent (Japanese Patent Laid-Open No. 2010-31223), 4.22 g of the compound (D-2) synthesized in the reference patent (Japanese Patent Laid-Open No. 2011-207765), 0.02 g of DMAP (Dimethylaminopyridine) (manufactured by Wako Junyaku Industries), 0.20 g of BHT (Butylated hydroxy toluene) (manufactured by Wako Junyaku Industries), and 58 g of chloroform (manufactured by Kanto Chemical Industries) were added and mixed. IPC (Isophthaloyl chloride, isophthalic acid dichloride) (manufactured by Wako Junyaku Industries (Co., Ltd.) 4.05 g were added and reacted at 0°C overnight. After completion of the reaction, the insoluble components were removed by filtration. The obtained chloroform solution was added dropwise to acetonitrile (manufactured by Wako Junyaku Industries (Co., Ltd.) in an amount 3 times the mass of chloroform contained in the solution to precipitate a solid. Subsequently, the precipitated solid was taken out by filtration, washed three times with 20 g of acetonitrile, and dried under reduced pressure at 30°C to obtain 11.75 g of a polymerizable liquid crystal compound (2-1-1). The yield of the polymerizable liquid crystal compound (2-1-1) was 81% based on compound (D-2).

Synthesis Example 2: Preparation of a mixture of polymerizable liquid crystal compound (1) and polymerizable liquid crystal compound (2) [Chemical 43]

A 100 mL four-necked flask equipped with a Dai's condenser and a thermometer was placed under a nitrogen atmosphere. Compound (E-1) (10.91 g), compound (D-2) (4.22 g), compound (F-3) (Wako Jun Chemical Industries, Ltd., 0.06 g), DMAP (Wako Jun Chemical Industries, Ltd., 0.02 g), BHT (Wako Jun Chemical Industries, Ltd., 0.20 g), and chloroform (Kanto Chemical Industries, Ltd., 58 g) were added and mixed. Then, 4.05 g of IPC (Wako Jun Chemical Industries, Ltd.) was added using a dropping funnel and the mixture was reacted overnight at 0°C. After completion of the reaction, the insoluble components were removed by filtration. The obtained chloroform solution was added dropwise to acetonitrile (manufactured by Wako Junyaku Industries, Ltd.) having a mass three times that of the chloroform contained in the solution, thereby precipitating a solid. The precipitated solid was then removed by filtration, washed three times with 20 g of acetonitrile, and dried under reduced pressure at 30°C to obtain 12.34 g of a mixture of polymerizable liquid crystal compound (2-1-1) and polymerizable liquid crystal compound (1-1-1). The obtained mixture contained 5.0% of polymerizable liquid crystal compound (1-1-1) relative to the total mass of the mixture. The yield of the mixture was 85.0% based on compound (D-2). In addition, n in the above formula (1-1-1) is n=2.

Synthesis Examples 3 to 13 Liquid crystal mixtures (1) to (12) containing a polymerizable liquid crystal compound (2-1-1) and any one of the polymerizable liquid crystal compounds (1-1-2) to (1-1-10) were prepared in the same manner as in Synthesis Example 2, except that compounds (F-4) to (F-10), (F-1), or (F-2) shown in Table 1 were used instead of compound (F-3). Furthermore, each of the polymerizable liquid crystal compounds (1-1-2) to (1-1-10) has a structure in which the propylene group in the structure represented by -O-CO-(C ₃ H ₆ )-CO-O- in the above formula (1-1-1) is substituted with an aliphatic alkyl group or an alicyclic group derived from compound (F-4) to (F-10), (F-1), or (F-2).

[Table 1] Liquid crystal mixture No. Compound (F) Polymerizable liquid crystal compounds (1) Liquid crystal compounds/mixtures Kind The structure of M in formula (1) Kind Area percentage (%) Yield (g) Yield (%) Synthesis example 1 - - - - 0.0 11.76 81.0 Synthesis example 2 (1) F-3 (1-1-1) 5.0 12.34 85.0 Synthesis example 3 (2) F-4 (1-1-2) 12.3 9.69 66.8 Synthesis example 4 (3) F-5 (1-1-3) 11.8 October 18 70.2 Synthesis example 5 (4) F-6 (1-1-4) 6.3 11.77 81.1 Synthesis example 6 (5) F-6 (1-1-4) 12.7 9.81 67.6 Synthesis Example 7 (6) F-6 (1-1-4) 41.3 12.05 83.0 Synthesis example 8 (7) F-7 (1-1-5) 6.4 11.13 76.7 Synthesis example 9 (8) F-8 (1-1-6) 42.5 12.23 84.3 Synthesis example 10 (9) F-9 (1-1-7) 8.6 11.64 80.2 Synthesis Example 11 (10) F-10 (1-1-8) 47.2 11.54 79.5 Synthesis example 12 (11) F-1 (1-1-9) 5.9 11.93 82.2 Synthesis example 13 (12) F-2 (1-1-10) 6.4 12.54 86.4

<Solubility Evaluation> At 25°C, 1.00 g of N-methylpyrrolidone (NMP) and a stirring rod were placed in a vial. While stirring with a magnetic stirrer (HS-30DN, AS ONE), the above-mentioned synthesized compounds were added until a dissolved residue was visually confirmed. After confirming the dissolved residue, the solubility of each liquid crystal mixture and polymerizable liquid crystal compound in NMP was calculated as (weight of each liquid crystal mixture and polymerizable liquid crystal compound)/(weight of each liquid crystal mixture and polymerizable liquid crystal compound + weight of NMP) and expressed as weight percentage concentration. The results are shown in Table 3.

<Preparation of a polymerizable liquid crystal composition> Example 1 A liquid crystal mixture (1) of the polymerizable liquid crystal compound (1-1-1) and the polymerizable liquid crystal compound (2-1-1) obtained in Synthesis Example 2 was added to a vial tube. A polymerization initiator, a leveling agent, a polymerization inhibitor, and a solvent were added according to the composition shown in Table 2. The mixture was stirred at 80°C for 30 minutes using a carousel to obtain a polymerizable liquid crystal composition (1). The amounts of the polymerization initiator, leveling agent, and polymerization inhibitor shown in Table 2 are the amounts added relative to 100 parts by mass of the liquid crystal mixture (1). The amount of the solvent was set so that the mass % of the solid content relative to the total amount of the polymerizable liquid crystal composition was 13%.

[Table 2] Polymerization initiator Leveling agent polymerization inhibitors Added amount [weight] 6.0 0.1 0.2

Polymerization initiator: 2-benzyl-2-dimethylamino-1-(4-oxo-1,1-dopamine-phenyl)butan-1-one (Irgacure 369, manufactured by BASF Japan) Leveler: Polyacrylate compound (BYK-361N, manufactured by BYK-Chemie Japan) Polymerization inhibitor: BHT (manufactured by Wako Junyaku Industries Co., Ltd.) Solvent: N-methylpyrrolidone (NMP, manufactured by Kanto Chemical Co., Ltd.)

Example 2 510 mg of the liquid crystal mixture (2) of the polymerizable liquid crystal compound (1-1-2) obtained in Synthesis Example 3 and the polymerizable liquid crystal compound (2-1-1) and 490 mg of the compound (2-1-1) obtained in Synthesis Example 1 were mixed and used as the polymerizable liquid crystal compound. The same operation as in Example 1 was followed, to obtain a polymerizable liquid crystal composition (2). The obtained polymerizable liquid crystal composition (2) was subjected to HPLC analysis under the above-mentioned measurement conditions, and the area percentage of the polymerizable liquid crystal compound (1-1-2) based on the total amount of the polymerizable liquid crystal compound (2-1-1) and the polymerizable liquid crystal compound (1-1-2) was calculated.

Examples 3 to 8 and 10 to 12 Except for using liquid crystal mixtures (2) to (10) instead of liquid crystal mixture (1), the same operation as in Example 1 was followed to obtain polymerizable liquid crystal compositions (3) to (8) and (10) to (12).

Example 9 500 mg of the liquid crystal mixture (8) of the polymerizable liquid crystal compound (1-1-6) obtained in Synthesis Example 9 and the polymerizable liquid crystal compound (2-1-1) and 500 mg of the compound (2-1-1) obtained in Synthesis Example 1 were mixed and used as the polymerizable liquid crystal compound. The same operation as in Example 1 was performed to obtain a polymerizable liquid crystal composition (9). The obtained polymerizable liquid crystal composition (9) was subjected to HPLC analysis under the above-mentioned measurement conditions to calculate the area percentage value of the polymerizable liquid crystal compound (1-1-6) based on the total amount of the polymerizable liquid crystal compound (2-1-1) and the polymerizable liquid crystal compound (1-1-6).

Comparative Example 1 Except for using the polymerizable liquid crystal compound (2-1-1) obtained in Synthesis Example 1 instead of the liquid crystal mixture (1), the same operation as in Example 1 was followed to obtain a polymerizable liquid crystal composition (13).

Comparative Examples 2 and 3 According to Table 3, the liquid crystal mixture (11) or (12) obtained in Synthesis Example 12 or 13 was used instead of liquid crystal mixture (1). The same operation as in Example 1 was followed, and polymerizable liquid crystal compositions (14) and (15) were obtained.

<Determination of Phase Transition Temperature> 1000 mg of each of the liquid crystal mixtures used in the polymerizable liquid crystal compositions (1) to (15) was weighed and placed in a vial tube. 2 g of chloroform was then added to dissolve the mixture. The resulting solution was applied to a glass substrate with a rubbed PVA alignment film and dried. The substrate was placed in a cooling and heating device ("LNP94-2" manufactured by Japan High Tech), heated from room temperature to 180°C, and then cooled to room temperature. The temperature change was observed using a polarizing microscope (LEXT, manufactured by Olympus Corporation), and the temperature at which the nematic phase was formed was measured as the nematic phase transition temperature. The results are shown in Table 3.

[Table 3] polymerizable liquid crystal composition The structure of M in formula (1) Polymerizable liquid crystal compounds (1) Phase transition temperature (℃) Solubility (mass %) Kind Area percentage (%) Example 1 (1) (1-1-1) 5.0 144 21.9 Example 2 (2) (1-1-2) 6.3 136 12.5 Example 3 (3) (1-1-2) 12.3 137 9.4 Example 4 (4) (1-1-3) 11.8 127 15.8 Example 5 (5) (1-1-4) 6.3 136 19.0 Example 6 (6) (1-1-4) 12.7 138 19.9 Example 7 (7) (1-1-4) 41.3 135 18.5 Example 8 (8) (1-1-5) 6.4 138 21.8 Example 9 (9) (1-1-6) 21.2 136 22.7 Example 10 (10) (1-1-6) 42.5 134 29.0 Example 11 (11) (1-1-7) 8.6 139 20.3 Example 12 (12) (1-1-8) 47.2 133 14.4 Comparative example 1 (13) - - - 154 6.1 Comparative example 2 (14) (1-1-9) 5.9 155 7.0 Comparative example 3 (15) (1-1-10) 6.4 159 11.0

<Measurement of optical properties (α value)> For the polymerizable liquid crystal compositions (1), (3), (4), (6), (8), (10) to (12), and (15) wherein M in formula (1) is an aliphatic hydrocarbon group, optical films (retardation films) were prepared and their optical properties were evaluated. The results are shown in Table 4. [Preparation of a composition for forming a photo-alignment film] The following components were mixed and the resulting mixture was stirred at 80°C for 1 hour to obtain a composition for forming a photo-alignment film. Photo-alignment material represented by the following formula (5 parts): [Chemical 44] (Number average molecular weight: approximately 28,000) Solvent (95 parts): Cyclopentanone

[Production of Optical Film (Phase Difference Film)] An optical film was produced as follows. A cycloolefin polymer film (COP) (ZF-14, manufactured by Zeon Co., Ltd., Japan) was treated once using a corona treatment device (AGF-B10, manufactured by Kasuga Electric Co., Ltd.) at an output of 0.3 kW and a treatment speed of 3 m/min. The composition for forming the optical alignment film was applied to the corona-treated surface using a rod coater and dried at 80°C for 1 minute. Polarized UV exposure was performed using a polarized UV irradiation device (SPOT CURE SP-7, manufactured by Ushio Electric Co., Ltd.) at a cumulative light dose of 100 mJ/ ^cm² . The thickness of the resulting alignment film was measured using a laser microscope (LEXT, manufactured by Olympus Corporation) and found to be 100 nm.

The polymerizable liquid crystal compositions (1), (3), (4), (6), (8), (10) to (12) and (15) were coated on the alignment film using a bar coater. After drying at 120°C for 1 minute, the films were irradiated with ultraviolet rays (wavelength: 365 nm, cumulative light intensity at 365 nm: 1000 mJ/ ^cm2 ) using a high-pressure mercury lamp (UniQure VB-15201BY-A, manufactured by Niuwei Electric Co., Ltd.) in a nitrogen atmosphere to prepare optical films.

The optical film prepared as described above was used as a test sample, and the front phase difference for light with a wavelength of 450 nm and a wavelength of 550 nm was measured using a measuring instrument ("KOBRA-WR" manufactured by Oji Scientific Instruments Co., Ltd.), and the α value was calculated as Re(450)/Re(550).

[Table 4] polymerizable liquid crystal composition The structure of M in formula (1) Polymerizable liquid crystal compounds (1) Optical characteristics α value Example 1 (1) (1-1-1) 0.842 Example 3 (3) (1-1-2) 0.825 Example 4 (4) (1-1-3) 0.840 Example 6 (6) (1-1-4) 0.825 Example 8 (8) (1-1-5) 0.843 Example 10 (10) (1-1-6) 0.820 Example 11 (11) (1-1-7) 0.851 Example 12 (12) (1-1-8) 0.791 Comparative example 3 (15) (1-1-10) 0.872

Claims (8)

A polymerizable liquid crystal compound represented by formula (1): [In formula (1), k11, k12 and l each independently represent an integer of 1 or greater; ^B11 and ^B12 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 - ^CO- , -O- _CH2- , _-CH2 -O-, -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom or an alkyl group having 1 to 4 carbon atoms; ^E11 and ^E12 each independently represent ^-CR1R2- _{, -CH2} - ^CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ¹¹ and G ¹² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R wherein ^A11 and ^A12 independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R3, ^-OR3 , a cyano group, or a nitro group; wherein ^F11 and ^F12 independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with ^-OR3 or a halogen atom, and the _-CH2- contained in the alkanediyl group may be substituted with ^-O- or -CO-; wherein ^P11 and ^P12 independently represent a hydrogen atom or a polymerizable group (wherein ^P11 and P12 independently represent a hydrogen atom or a polymerizable group). ^{11 and} Ar ¹² are each independently a group represented by the following formula (Ar-1): [In formula (Ar-1), * represents a bonding moiety; Q ¹ represents -S-, -O-, or -NR ¹¹ -; R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent; Y ¹ represents an alkyl group having 1 to 6 carbon atoms, an aromatic alkyl group or an aromatic heterocyclic group which may have a substituent; Z ¹ and Z ² each independently represent a hydrogen atom, an aliphatic alkyl group or an alkoxy group having 1 to 20 carbon atoms, an alicyclic alkyl group having 3 to 20 carbon atoms, a monovalent aromatic alkyl group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR ¹¹ R ¹² , or -SR ¹¹ ; Z ¹ and Z ² may be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring; R ¹¹ and R ^{1 and 2} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms]. A polymerizable liquid crystal composition comprising the polymerizable liquid crystal compound of claim 1 and a polymerizable liquid crystal compound represented by formula (2), [Chemical 48] [In formula (2), k21 and k22 each independently represent an integer of 1 or greater; ^B21 and ^B22 each independently represent ^-CR1R2- , ^-CH2 - _CH2- , _-O- , -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR1-, ^-NR2 -CO-, -O- ^CH2- , -CH2- _O- , -S- _CH2- , _-CH2 -S-, or a single bond; ^R1 and ^R2 each independently represent a hydrogen atom, a fluorine atom, _or ^an alkyl group having 1 to 4 carbon atoms; ^E21 and ^E22 each independently represent ^-CR1R2- , _-CH2 - _CH2 -, -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -C(=S)-O-, -OC(=S)-, -OC(=S)-O-, -CO-NR 1 -, -NR 2 -CO-, -O-CH ² -, -CH ² -O-, -S-CH _{2 -} , -CH _{2 -S-} , or a single bond; G ²¹ and G ²² each independently represent a divalent alicyclic alkyl group having 3 to 16 carbon atoms, wherein the hydrogen atom contained in the alicyclic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group, wherein the -CH ₂ - contained in the alicyclic alkyl group may be substituted with -O-, -S-, or -NH-, and R A ²¹ and A ²² each independently represent a divalent alicyclic alkyl group having ³ to 16 carbon atoms, or a divalent aromatic alkyl group having 6 to 20 carbon atoms, wherein the hydrogen atoms contained in the alicyclic alkyl group and the aromatic alkyl group may be substituted with a halogen atom, -R ³ , -OR ³ , a cyano group, or a nitro group; F ²¹ and F ²² each independently represent an alkanediyl group having 1 to 12 carbon atoms, wherein the hydrogen atoms contained in the alkanediyl group may be substituted with -OR ³ or a halogen atom, and the -CH ₂ - contained in the alkanediyl group may be substituted with -O- or -CO-; P ²¹ and P ²² each independently represent a hydrogen atom or a polymerizable group (wherein P ²¹ and P ²² , at least one of which is a polymerizable group); Ar ²¹ each independently represents a group represented by the following formula (Ar-1): [In formula (Ar-1), * represents a bonding moiety; Q ¹ represents -S-, -O-, or -NR ¹¹ -; R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent; Y ¹ represents an alkyl group having 1 to 6 carbon atoms, an aromatic alkyl group or an aromatic heterocyclic group which may have a substituent; Z ¹ and Z ² each independently represent a hydrogen atom, an aliphatic alkyl group or an alkoxy group having 1 to 20 carbon atoms, an alicyclic alkyl group having 3 to 20 carbon atoms, a monovalent aromatic alkyl group having 6 to 20 carbon atoms, a halogen atom, a cyano group, a nitro group, -NR ¹¹ R ¹² , or -SR ¹¹ ; Z ¹ and Z ² may be bonded to each other to form an aromatic ring or an aromatic heterocyclic ring; R ¹¹ and R ^{1 and 2} each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms]. The polymerizable liquid crystal composition of claim 2, wherein the ratio of the peak area of the polymerizable liquid crystal compound (1) to the total peak area of the polymerizable liquid crystal compound (1) and the polymerizable liquid crystal compound (2) measured by liquid chromatography is greater than or equal to 0.1% and less than or equal to 50%. The polymerizable liquid crystal composition of claim 2 or 3, wherein the groups represented by A ¹¹ , A ¹² , B ¹¹ , B 12 , E ¹¹ , E ¹² , F ¹¹ , F ¹² , G ¹¹ , G ¹² , P ¹¹ and ^{P 12 in} formula (1) are the same as the groups represented by A ²¹ , A ²² , B ²¹ , B ²² , E ²¹ , E ²² , F ²¹ , F ²² , G ²¹ , G ²² , P ²¹ and P ²² in formula (2), respectively, and the groups represented by Ar ¹¹ and Ar ¹² in formula (1) are the same as the group represented by Ar ²¹ in formula (2). The polymerizable liquid crystal composition of claim 2 or 3 further comprises a photopolymerization initiator and an organic solvent. A phase difference film is formed from the polymerizable liquid crystal composition according to any one of claims 2 to 5. A polarizing plate comprising the phase difference film of claim 6. An optical display comprising the polarizing plate of claim 7.