JP2005141206A - Polymerizable liquid crystalline composition and liquid crystal film produced from the composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymerizable liquid crystalline compound containing no functional group difficult to synthesize, and also to provide a cholesteric aligned liquid crystal film which does not require a complicated process such as photoirradiation under an inert gas atmosphere, and has excellent alignment retention properties and mechanical strength after the liquid crystal alignment is fixed. <P>SOLUTION: The polymerizable liquid crystalline composition is composed of an oxetane compound (A) having an optically active part expressed by a general formula (1) Z<SP>1</SP>-(CH<SB>2</SB>)<SB>n</SB>-L<SP>1</SP>-P<SP>1</SP>-L<SP>2</SP>-C<SP>1</SP>-L<SP>2</SP>-P<SP>1</SP>-L<SP>1</SP>-(CH<SB>2</SB>)<SB>n</SB>-Z<SP>1</SP>, a side-chain liquid crystalline polymeric substance (B) having an oxetanyl group, and a photo cation generator and/or a thermal cation generator (C), and the weight ratio of (A):(B) is 0.01:99.9 to 60:40. In the formula (1), Z<SP>1</SP>denotes a specific oxetanyl group, L<SP>1</SP>and L<SP>2</SP>denote either of single bond, -O-, -O-CO- and -CO-O- respectively, P<SP>1</SP>denotes phenylene group, substituted phenylene group or biphenylene group, C<SP>1</SP>denotes an optically active part, and n denotes an integer of 0 to 8. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a polymerizable liquid crystal composition and a liquid crystal film produced from the composition.

  In recent years, research and development for applying liquid crystal compounds to optical materials has been actively conducted, and many have already been put into practical use. When a liquid crystal compound is applied to an optical material, it is essential to fix the liquid crystal alignment structure and hold it under actual use conditions. As a method for maintaining the alignment structure of the liquid crystal, a method using a polymerizable liquid crystal compound, a method using a polymer liquid crystal compound, a method using a polymer liquid crystal compound having a reactive group capable of crosslinking, and the like have been proposed.

  As a method of using a polymer liquid crystal compound having a reactive group capable of cross-linking, a (meth) acrylate is formed of a mesogen portion composed of two or more benzene rings or similar rings, a spacer portion composed of a hydrocarbon chain, and both ends or one end. A polymerizable liquid crystal compound having a radically polymerizable reactive group such as a group is known (for example, see Patent Document 1). In this method, these polymerizable liquid crystal compounds are heated and melted or applied as a solution, and then dried as necessary to form a liquid crystal layer on the alignment substrate, and in a state where the liquid crystals are aligned using means such as heating, Polymerization by light irradiation is performed to fix the liquid crystal alignment. However, this method has to suppress the polymerization inhibiting action due to oxygen in the air, and requires complicated operations such as light irradiation in an inert gas atmosphere and the accompanying improvement of the apparatus. In addition, since the (meth) acrylate group is easily polymerized by light or heat, careful attention is required during synthesis.

As a method using a polymer liquid crystal compound, a liquid crystalline polyester excellent in alignment retention ability has been proposed (for example, see Patent Document 2). However, with the widespread use of mobile devices, optical film made of these liquid crystalline polyesters is required to have orientation retention ability and better mechanical strength in a more severe use environment.
On the other hand, as a method of using a polymer liquid crystal compound having a polymerizable reactive group, a method of introducing a polymerizable reactive group into a polymer main chain and a method of introducing a monomer unit having a polymerizable reactive group into a side chain are proposed. However, in any of these methods, liquid crystallinity is lowered, so that a large amount of polymerizable reactive groups must be introduced before the mechanical strength can be sufficiently increased. There are limits and other approaches are required.

Japanese Patent Laid-Open No. 11-80081 JP-A-11-158258 JP-A-9-3454

  The present invention provides a polymerizable liquid crystal compound that does not contain a functional group that is difficult to synthesize such as a (meth) acrylate group or an epoxy group, and by using the compound, light irradiation under an inert gas atmosphere can be performed. An object of the present invention is to provide a cholesteric alignment liquid crystal film that does not require such a complicated process and is excellent in alignment retention ability and mechanical strength after the alignment of liquid crystal alignment.

The inventors of the present invention have studied a polymerizable liquid crystal compound that is easy to synthesize and has good liquid crystal orientation, and as a result, found a polymerizable liquid crystal compound having a cationic polymerizable oxetanyl group as a polymerizable reactive group. By polymerizing the polymerizable liquid crystal compound after liquid crystal alignment and forming a film, a new cholesteric liquid crystal film excellent in alignment retention ability and mechanical strength after liquid crystal alignment fixation was developed.

That is, the present invention relates to an oxetane compound (A) having an optically active site represented by the following general formula (1), a side-chain liquid crystalline polymer substance (B) having an oxetanyl group, and a photocation generator. And / or a thermal cation generator (C), wherein the weight ratio of the compound (A): the polymeric substance (B) is in the range of 0.01: 99.99 to 60:40. About.
^{_{Z 1 - (CH 2) n}} -L 1 -P 1 -L 2 -C 1 -L 2 -P 1 -L 1 - (CH 2) n -Z 1 (1)
(In formula (1), Z ¹ represents any one of the following formulas (2) to (4), and L ¹ and L ² are each independently a single bond, —O—, —O—CO—, or Represents one of -CO-O- and P ¹
Represents the following formula (5) or (6), C ¹ represents an optically active site, and in formula (5), X represents a hydrogen atom, a methyl group or a halogen atom, and n represents an integer of 0 to 8. . )

The present invention also relates to the polymerizable liquid crystal composition, wherein C ¹ in the general formula (1) is a group represented by the following general formula (7) or (8).

  In the present invention, the layer of the polymerizable liquid crystal composition described above is formed on a film having alignment ability, the molecules are cholesterically aligned to fix the alignment, and then polymerized by light and / or heat. It relates to the liquid crystal film obtained.

Hereinafter, the present invention will be described in more detail.
The polymerizable liquid crystal composition of the present invention includes an oxetane compound (A) having an optically active site represented by the following general formula (1), a side-chain liquid crystalline polymer substance (B) having an oxetanyl group, and light. It comprises a cation generator and / or a thermal cation generator (C).
^{_{Z 1 - (CH 2) n}} -L 1 -P 1 -L 2 -C 1 -L 2 -P 1 -L 1 - (CH 2) n -Z 1 (1)
In the general formula (1), Z ¹ represents any one of the following formulas (2) to (4), and L ¹ and L ²
Each independently represents a single bond, —O—, —O—CO—, or —CO—O—, P ¹ represents the following formula (5) or (6), and C ¹ represents optical: Represents an active site, and in formula (5), X represents a hydrogen atom, a methyl group or a halogen atom, and n represents an integer of 0-8.

In the present invention, in the formula (1), the mesogen moiety represented by “-L ¹ -P ¹ -L ² -C ¹ -L ² -P ¹ -L ^1- ” has 2 to 4 aromatic rings. In the 1,4-position, it has a structure bonded via a direct bond (single bond), an ether bond (—O—) or an ester bond (—CO—O—), and the aromatic ring has a methyl group, A halogen atom such as a fluorine atom or a chlorine atom may be substituted.
In Formula (1), L ¹ and L ² are each independently a single bond (here, a case where groups on both sides are directly bonded without using a group represented by L), —O—. , -O-CO-, or -CO-O-, and P ¹ represents the above formula (5) or formula (6).
Specific examples of the formula (5) include a 1,4-phenylene group, a methyl group-substituted 1,4-phenylene group, a fluorine-substituted 1,4-phenylene group, and a chlorine-substituted 1,4-phenylene group.
In formula (1), C ¹ represents an optically active site, and it is essential that at least some kind of chirality be present in the molecule. For example, a site having one or more asymmetric carbons, a site having an asymmetric point on a heteroatom such as a chiral amine or chiral sulfoxide, or a site having axial asymmetry such as cumulene or binaphthol. Can be illustrated. Preferable specific examples of C ¹ include formula (7) and formula (8).

Further, as the “—L ¹ -P ¹ -L ² —” moiety in the formula (1), specifically, a structure represented by the following formula is preferable, and “—L ² -P ¹ — The same combination is preferable for the “L ^1- ” portion.

In the present invention, the spacer moiety represented by “— (CH ₂ ) _n —” in the formula (1) is a single bond (here, n is 0) or has 1 to 8 carbon atoms. It is a divalent linear hydrocarbon group. In general, if the spacer portion is too long, the heat resistance of the cured film may be deteriorated. Therefore, the carbon number of the spacer portion is preferably 0 to 6.
The reactive oxetane moiety (Z ¹ ) is preferably any of the following formulas (2) to (4) from the viewpoint of ease of synthesis and the like.

  As a method for synthesizing the oxetane compound having an optically active site used in the present invention, a method used in usual organic chemistry can be applied, and it is not particularly limited. For example, after the oxetanyl group portion and the spacer portion are first bonded by a method such as Williamson's ether synthesis, the same ester as the mesogenic portion previously synthesized by an ester synthesis method using a condensing agent such as DCC (dicyclohexylcarbodiimide). After combining the synthesis method, or the oxetanyl group portion and the spacer portion, and then combining one aromatic ring with a carboxyl group by a method such as ether synthesis, and finally synthesizing with an ester synthesis method with hydroquinone The method of doing is mentioned.

At this time, since the oxetanyl groups at both ends have cationic polymerizability, it is necessary to select reaction conditions in consideration of causing side reactions such as polymerization and ring opening under strong acidic conditions. The oxetanyl group is less likely to cause a side reaction than an epoxy group that is a similar cationically polymerizable functional group. Further, various compounds such as similar alcohols, phenols and carboxylic acids may be reacted one after another, and utilization of protecting groups may be considered as appropriate. The synthesized crude liquid crystalline oxetane compound may be purified by a method such as recrystallization or column chromatography. In particular, recrystallization is an effective means for those having a certain degree of crystallinity, and even a compound that cannot be recrystallized at room temperature can be recrystallized by cooling to a low temperature such as −20 ° C. is there. The crude oxetane compound thus obtained mainly consists of ¹ H-
Identification is possible by analytical means such as NMR (nuclear magnetic resonance).

As an oxetane compound having an optically active site used in the present invention, in general formula (1), Z ¹ is a group represented by formula (2), L ¹ is —O—, and L ² is —CO—. Particularly preferred is O— and P ¹ is a 1,4-phenylene group or a 1,4′-biphenylene group.
In the polymerizable liquid crystal composition of the present invention, two or more compounds included in the general formula (1) can be mixed and used as the oxetane compound of the component (A).

  The component (B) in the polymerizable liquid crystal composition of the present invention is a side chain liquid crystal polymer substance having an oxetanyl group. Among these, a side chain type liquid crystalline polymer substance containing 5 to 100 mol% of the unit represented by the general formula (9) is particularly preferable.

In the general formula (9), R ¹ represents hydrogen or a methyl group, R ² represents hydrogen, a methyl group or an ethyl group, and L ³ and L ⁴ each independently represent a single bond, —O—, —O. -CO- or -CO-O- is represented, M represents any one of the following formulas (10) to (12), and q and p each independently represent an integer of 0 to 10.
^{-P 2 -L 5 -P 3 -L 6} -P 4 (10)
^{-P 2 -L 5 -P 4 - (} 11)
-P ⁴ - (12)

In the above formulas (10) to (12), P ² and P ³ each independently represent a group selected from formula (13), P ⁴ represents a group selected from formula (14), and L ⁵ and L ⁶ each independently represents a single bond, —CH═CH—, —C≡C—, —O—, —O—CO— or —CO—O—.

The unit represented by the general formula (9) can be derived by radical polymerization or anionic polymerization of the (meth) acrylic group portion of the meth (acrylic) compound having an oxetanyl group represented by the following general formula (15).

R ¹ , R ² , L ³ , L ⁴ , M, q and p in the formula (15) are the same as those in the formula (9).

  The side chain type liquid crystalline polymer substance having an oxetanyl group is a radical or anionic polymerization of a (meth) acrylic group part of a (meth) acrylic compound having an oxetanyl group represented by the general formula (15) or other It can be easily synthesized by copolymerizing with a (meth) acrylic compound. Polymerization conditions are not particularly limited, and normal conditions can be employed.

  As an example of radical polymerization, a (meth) acrylic compound is dissolved in a solvent such as dimethylformamide (DMF), and 2,2′-azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), or the like is used as an initiator. And a method of reacting at 80 to 90 ° C. for several hours. Moreover, in order to make the liquid crystal phase appear stably, copper bromide (II) / 2,2′-bipyridyl series, 2,2,6,6-tetramethylpiperidinooxy free radical (TEMPO) series, etc. are used. A method of controlling the molecular weight distribution by conducting living radical polymerization as an initiator is also effective. These radical polymerizations must be carried out strictly under deoxygenation conditions.

  Examples of anionic polymerization include a method in which a (meth) acrylic compound is dissolved in a solvent such as tetrahydrofuran (THF) and reacted with a strong base such as an organic lithium compound, an organic sodium compound, or a Grignard reagent as an initiator. In addition, the molecular weight distribution can be controlled by optimizing the initiator and the reaction temperature for living anionic polymerization. These anionic polymerizations must be performed strictly under dehydration and deoxygenation conditions.

  In addition, the (meth) acrylic compound used for copolymerization at this time is not particularly limited, and any polymer material can be used as long as it exhibits liquid crystallinity. In order to improve liquid crystallinity, a (meth) acrylic compound having a mesogenic group is preferable. Specifically, a (meth) acrylic compound represented by the following formula is particularly preferable.

The side chain type liquid crystalline polymer substance (B) in the present invention preferably contains 5 to 100 mol% of the unit represented by the formula (9), and particularly preferably contains 10 to 100 mol%.
Further, the side chain type liquid crystalline polymer substance (B) in the present invention preferably has a weight average molecular weight of 2,000 to 100,000, particularly preferably 5,000 to 50,000.

The component (C) in the polymerizable liquid crystal composition of the present invention is a photo cation generator and / or a thermal cation generator.
Since the polymerizable liquid crystal composition of the present invention comprises a compound having a cationic polymerizable oxetanyl group, a cation generator is required for the polymerization (curing). These cation generators are preferably compounds capable of generating cations by external stimuli such as light and / or heat, such as compounds having a trichloromethyl group or a quinonediazide group, organic sulfonium salt systems, iodonium salt systems, phosphonium salts. Etc. If necessary, various sensitizers may be used in combination.

The photo cation generator in the present invention means a compound capable of generating a cation by irradiating with light of an appropriate wavelength, and examples thereof include organic sulfonium salt systems, iodonium salt systems, phosphonium salt systems, and the like. I can do it. Antimonates, phosphates, borates and the like are preferably used as counter ions of these compounds. Specific examples of the compound include Ar ₃ S ⁺ SbF ₆ ⁻ , Ar ₃ P ⁺ BF ₄ ⁻ and Ar ₂ I ⁺ PF ₆ ⁻ (wherein Ar represents a phenyl group or a substituted phenyl group). In addition, sulfonate esters, triazines, diazomethanes, β-ketosulfone, iminosulfonate, benzoinsulfonate, and the like can also be used.

  Further, the thermal cation generator referred to in the present invention is a compound that can generate a cation when heated to an appropriate temperature, for example, benzylsulfonium salts, benzylammonium salts, benzylpyridinium salts, benzylphosphonium salts, hydrazinium salts. Carboxylic acid esters, sulfonic acid esters, amine imides, antimony pentachloride-acetyl chloride complexes, diaryliodonium salts-dibenzyloxycopper, boron halide-tertiary amine adducts, and the like.

  The mixing ratio of the oxetane compound (A) and the side chain liquid crystalline polymer substance (B) in the polymerizable liquid crystal composition of the present invention is 0.01: by weight ratio of the compound (A): the polymer substance (B). It is 99.99-60: 40, Preferably it is 0.1: 99.9-50: 50, More preferably, it is 0.5: 99.5-30: 70. When the compound (A) is less than 0.01%, cholesteric alignment may not be formed. Further, when the compound is contained in an amount of more than 60%, disclination may occur, which is not desirable.

  The amount of the cation generator (C) added to the polymerizable liquid crystal composition is such that the structure of the mesogen part or spacer part constituting the side chain type liquid crystalline polymer substance (B) to be used, the oxetanyl group equivalent, the liquid crystal However, it is generally 100 mass ppm to 20 mass%, preferably 1000 mass ppm to 10 mass%, more preferably, based on the side chain type liquid crystalline polymer substance (B). It is 0.2 mass%-7 mass%, Most preferably, it is the range of 0.5 mass%-5 mass%. When the addition amount of the cation generator is less than 100 mass ppm, the amount of the generated cation may not be sufficient and the polymerization may not proceed. When the addition amount is more than 20 mass%, it remains in the liquid crystal film. This is not preferable because the decomposition residue of the cation generator is increased, and the light resistance may be deteriorated.

The polymerizable liquid crystal composition having an oxetanyl group of the present invention can be easily aligned at a low temperature, and then the oxetanyl group is polymerized by cationic polymerization, whereby crosslinking occurs and the alignment is fixed and excellent in heat resistance. A liquid crystal film is obtained.
Therefore, the layer of the polymerizable liquid crystal composition of the present invention is formed on a film having alignment ability, the molecules are cholesterically aligned to fix the alignment, and then polymerized by light and / or heat to achieve heat resistance. A liquid crystal film having excellent properties can be obtained.

Next, a method for producing a liquid crystal film using the polymerizable liquid crystal composition of the present invention will be described. The method for producing the liquid crystal film is not limited to these, but it is desirable to take each step shown in the following method.
The liquid crystal film produced from the polymerizable liquid crystal composition of the present invention has a form (alignment film / (alignment film) / liquid crystal film) as formed on the alignment film having the alignment ability, and a transparent substrate different from the alignment film. Any form of a liquid crystal film transferred to a film or the like (transparent substrate film / liquid crystal film) or a liquid crystal film single layer form (liquid crystal film) may be used.

  Examples of the film having orientation ability include polyimide, polyamide, polyamideimide, polyphenylene sulfide, polyphenylene oxide, polyether ketone, polyether ether ketone, polyether sulfone, polysulfone, polyethylene terephthalate, polyethylene naphthalate, polyarylate, and triphenyl. Examples thereof include films of acetyl cellulose, epoxy resin, phenol resin, polyvinyl alcohol, and stretched films of these films.

  Some of these films exhibit sufficient alignment ability for the polymerizable liquid crystal composition of the present invention without performing treatment for expressing the alignment ability again depending on the production method. In the case where it does not show the performance, etc., these films are stretched under appropriate heating as necessary, and the film surface is rubbed in one direction with rayon cloth, conductive nylon, cotton, acrylic fiber, etc., so-called rubbing treatment is performed. An alignment film made of a known alignment agent such as polyimide, polyvinyl alcohol, or a silane coupling agent is provided on the film to perform rubbing treatment, oblique vapor deposition treatment such as silicon oxide, or an appropriate combination thereof. An expressed film may be used. In addition, a metal plate such as aluminum, iron, or copper having various fine grooves on the surface, various glass plates, or the like can be used as the alignment substrate.

  When an oriented film that is not optically isotropic as the oriented film, or the obtained optical film is finally opaque in the intended wavelength range of use, is optically isotropic from the form formed on the oriented film. Or a form transferred onto a transparent film substrate in a wavelength region to be used finally. As the transfer method, for example, as described in JP-A-4-57017 and JP-A-5-333313, a liquid crystal film layer is bonded to another transparent film different from the alignment film via an adhesive. Examples include a method of transferring only the liquid crystal film by laminating the film substrate, if necessary, curing the adhesive / adhesive and peeling the alignment film from the laminate.

  Examples of the transparent film substrate include triacetyl cellulose films such as Fujitac (product of Fuji Photo Film Co., Ltd.), Konicatak (product of Konica Corp.), TPX film (product of Mitsui Chemicals Co., Ltd.), Arton Film ( JSR Co., Ltd.), Zeonex Film (Nippon ZEON Co., Ltd. product), Acryprene Film (Mitsubishi Rayon Co., Ltd. product), etc., and if necessary, a polarizing plate may be used as a transparent substrate. it can. Further, a quartz plate or a glass plate may be used. In addition, the said polarizing plate can be used regardless of the presence or absence of a protective layer.

The adhesive / adhesive used for transfer is not particularly limited as long as it is of optical grade. For example, acrylic, epoxy resin, ethylene-vinyl acetate copolymer system, rubber system, urethane system, and mixtures thereof And various reactive types such as a thermosetting type and / or a photocurable type and an electron beam curable type.
Since the reaction (curing) conditions for the reactive substances vary depending on the components constituting the adhesive / adhesive, the viscosity, the reaction temperature, and the like, conditions suitable for each may be selected. For example, in the case of the photo-curing type, the same light source may be used as in the case of the photocation generator described later, and the accelerating voltage in the case of the electron beam-curing type is usually 25 kV to 200 kV, preferably 50 kV to 100 kV.

  The liquid crystal film can be produced by a method of applying the polymerizable liquid crystal composition on the alignment substrate in a molten state, a method of applying a solution of the polymerizable liquid crystal composition on the alignment film, or the like. The coating film applied on the alignment substrate is subjected to drying, heat treatment (formation of cholesteric alignment of liquid crystal) and light irradiation and / or heat treatment (polymerization) to become a liquid crystal film.

  The solvent used for preparing the polymerizable liquid crystal composition solution is not particularly limited as long as it can dissolve the components constituting the polymerizable liquid crystal composition of the present invention and can be distilled off under appropriate conditions. Ketones such as acetone, methyl ethyl ketone, isophorone, butoxyethyl alcohol, hexyloxyethyl alcohol, ether alcohols such as methoxy-2-propanol, glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, ethyl acetate, methoxypropyl acetate, Esters such as ethyl lactate, phenols such as phenol and chlorophenol, amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, chloroform, tetrachloroethane , A halogenated hydrocarbon such or a mixture of these systems, such as dichlorobenzene are preferably used. Moreover, in order to form a uniform coating film on an oriented film, you may add surfactant, an antifoamer, a leveling agent, etc. to a solution. Furthermore, a dichroic dye, a normal dye, a pigment, or the like can be added within a range that does not hinder the expression of liquid crystallinity for the purpose of coloring.

  The application method is not particularly limited as long as the uniformity of the coating film is ensured, and a known method can be adopted. Examples thereof include a roll coating method, a die coating method, a dip coating method, a curtain coating method, and a spin coating method. After the application, a solvent removal (drying) step by a method such as a heater or hot air blowing may be added.

  Subsequently, liquid crystal cholesteric alignment is formed by heat treatment or the like if necessary. In this heat treatment, the liquid crystal is cholesterically aligned by the self-alignment ability inherent in the liquid crystal composition by heating to the liquid crystal phase expression temperature range of the used polymerizable liquid crystal composition. As the conditions for the heat treatment, the optimum conditions and limit values differ depending on the liquid crystal phase behavior temperature (transition temperature) of the polymerizable liquid crystal composition to be used, but it cannot be generally stated, but is usually 10 to 200 ° C, preferably 20 to 150 ° C. It is a range. If the temperature is too low, the alignment of the liquid crystal may not proceed sufficiently, and if the temperature is high, the alignment ability of the alignment film substrate or the like may be adversely affected. Moreover, about heat processing time, it is 3 seconds-30 minutes normally, Preferably it is the range of 10 seconds-10 minutes. If the heat treatment time is shorter than 3 seconds, the alignment of the liquid crystal may not be sufficiently completed, and if the heat treatment time exceeds 30 minutes, the productivity is extremely deteriorated. After the alignment of the liquid crystal is completed by heat treatment or the like, the liquid crystal composition on the alignment substrate is polymerized (cured) by light irradiation and / or heat treatment as it is. The purpose of this polymerization (curing) step is to fix the liquid crystal alignment state of the completed liquid crystal alignment by a polymerization (curing) reaction and transform it into a stronger film.

  The thickness of the liquid crystal film of the present invention obtained by fixing the cholesteric alignment obtained by the above method is not particularly limited, but is generally 0.3 to 20 μm, preferably from the viewpoint of mass productivity and production process. It is desirable that the thickness is 0.5 to 10 μm, more preferably 0.7 to 3 μm.

Since the liquid crystal film of the present invention has a cholesteric liquid crystal property, it exhibits not only an application in the field of optics and optoelectronics but also a very beautiful color when its selective reflection wavelength is in the visible light region. It is also useful as a fashion item. Moreover, the outstanding performance can be exhibited as a pigment, a color polarizing plate, a brightness enhancement film, and an anti-counterfeit film.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
In addition, the measurement of the transmission spectrum used in the Example used JASCO Corporation V-570.

(Synthesis Example 1)
In accordance with the following scheme 1, 3-ethyl-3-hydroxymethyloxetane (trade name OXT-101, manufactured by Toagosei Co., Ltd.) and isosorbide (manufactured by Tokyo Chemical Industry Co., Ltd.) as raw materials are used to produce an oxetanyl compound (1) having an optically active site. Synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 2)
According to the following scheme 2, 3-ethyl-3-hydroxymethyloxetane (trade name OXT-101, manufactured by Toagosei Co., Ltd.) and S-(−)-1,1′-bi-2-naphthol (manufactured by Kanto Chemical Co., Inc.) As a raw material, an oxetanyl compound (2) having an optically active site was synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 3)
According to the following scheme 3, 3-ethyl-3-hydroxymethyloxetane (trade name OXT-101, manufactured by Toagosei Co., Ltd.) and isosorbide (manufactured by Tokyo Chemical Industry Co., Ltd.) are used as raw materials, and an oxetanyl compound (3) having an optically active site is obtained. Synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 4)
According to the following scheme 4, an acrylic compound (4) having an oxetanyl group was synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 5)
According to the following scheme 5, the acrylic compound (5) having an oxetanyl group was synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 6)
According to the following scheme 6, an acrylic compound (6) having no oxetanyl group was synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 7)
According to the following scheme 7, an acrylic compound (7) having no oxetanyl group was synthesized. The obtained compound was purified by silica gel chromatography using a hexane / ethyl acetate solvent.

(Synthesis Example 8)
2,2′-azobisisobutyronitrile was prepared by mixing 20% by weight of the acrylic compound (4) synthesized in Synthesis Example 4 and 80% by weight of the acrylic compound (6) synthesized in Synthesis Example 6. As a initiator, DMF is used as a solvent, radical polymerization is carried out under nitrogen at 90 ° C. for 6 hours, and reprecipitation in methanol is carried out to synthesize a side-chain liquid crystalline polyacrylate (8) having an oxetanyl group. did.

(Synthesis Example 9)
25% by weight of the acrylic compound (5) synthesized in Synthesis Example 5 and 75% by weight of the acrylic compound (7) synthesized in Synthesis Example 7 were mixed to obtain 2,2′-azobisisobutyronitrile. As a initiator, DMF is used as a solvent, radical polymerization is performed under nitrogen at 90 ° C. for 6 hours, reprecipitation in methanol and purification is performed, thereby synthesizing a side chain type liquid crystalline polyacrylate (9) having an oxetanyl group. did.

(Example 1)
0.06 g of the oxetanyl compound (1) having an optically active site synthesized in Synthesis Example 1 and 0.94 g of the side-chain liquid crystalline polyacrylate (8) synthesized in Synthesis Example 8 were dissolved in cyclohexane, and triallyl in the dark. After adding 0.1 g of a 50% sulfonium hexafluoroantimonate propylene carbonate solution (Aldrich reagent), the insoluble matter was filtered with a polytetrafluoroethylene filter having a pore size of 0.45 μm to prepare a liquid crystal composition solution. . This solution was applied onto a 50 μm thick polyethylene naphthalate film (Teonex Q-51 manufactured by Teijin Limited) whose surface was rubbed with a rayon cloth using a spin coating method, and then dried on a hot plate at 60 ° C. It was. The liquid crystal composition layer on the obtained polyethylene naphthalate film was heated at 150 ° C. for 5 minutes and rapidly cooled to room temperature to obtain a liquid crystal composition layer.
Since the polyethylene naphthalate film used as the substrate has a large birefringence and is not preferable as an optical film, the obtained film is subjected to TAC (triacetyl) via an ultraviolet curable adhesive (UV-1394 manufactured by Toagosei Co., Ltd.). Transferred onto a (cellulose) film to obtain an optical film. That is, on the cured liquid crystal composition layer on the polyethylene naphthalate film, the adhesive UV-1394 was applied to a thickness of 5 mm, laminated with a TAC film, and 400 mj / cm ² from the TAC film side. After the ultraviolet light was irradiated to cure the adhesive, the polyethylene naphthalate film was peeled off.
When the obtained optical film was observed with a polarizing microscope, uniform cholesteric alignment of monodomains without disclination was observed. Moreover, when this film is seen from the front, it has selective reflection light peculiar to cholesteric, and when the transmission spectrum is evaluated by a spectroscope, a reduced region of transmitted light derived from selective reflection is found in the vicinity of 610 nm of the infrared region. It was.

(Example 2)
0.05 g of the oxetanyl compound (2) having an optically active site synthesized in Synthesis Example 2 and side chain type liquid crystalline polyacrylate (9) synthesized in Synthesis Example 9 were dissolved in 0.95 g of triethylene glycol dimethyl ether, and dark place was obtained. After adding 0.05 g of 50% propylene carbonate solution of triallylsulfonium hexafluoroantimonate (Aldrich reagent), the insoluble matter was filtered through a polytetrafluoroethylene filter having a pore size of 0.45 μm to obtain a liquid crystal composition solution. Adjusted. This solution was applied onto a polyethylene terephthalate film (T-60, manufactured by Toray Industries, Inc.) having a thickness of 50 μm whose surface was rubbed with a rayon cloth, and dried on a hot plate at 60 ° C. after the application. The liquid crystal composition layer on the obtained polyethylene terephthalate film was heated at 150 ° C. for 5 minutes and rapidly cooled to room temperature to obtain a liquid crystal composition layer.
Since the polyethylene terephthalate film used as a substrate has a large birefringence and is not preferable as an optical film, the obtained film is transferred onto a TAC film via an ultraviolet curable adhesive (UV-3400 manufactured by Toagosei Co., Ltd.). An optical film was obtained. That is, on the cured liquid crystal composition layer on the polyethylene terephthalate film, the adhesive UV-3400 is applied to a thickness of 5 mm, laminated with a TAC film, and an ultraviolet ray of 400 mj / cm ² from the TAC film side. After the light was irradiated to cure the adhesive, the polyethylene terephthalate film was peeled off.
When the obtained optical film was observed with a polarizing microscope, uniform cholesteric alignment of monodomains without disclination was observed. In addition, this film has selective reflection light peculiar to cholesteric when viewed obliquely. When the transmission spectrum was evaluated by a spectroscope, a reduced region of transmitted light derived from selective reflection was found around 780 nm. .

(Example 3)
0.08 g of the oxetanyl compound (3) having an optically active site synthesized in Synthesis Example 3 and the side chain type liquid crystalline polyacrylate (9) synthesized in Synthesis Example 9 were dissolved in 0.92 g N-methyl-2-pyrrolidone, After adding 0.1 g of syracure photocuring initiator (UVI-6992 manufactured by Dow Chemical Co., Ltd.) and 0.01 g of dibutoxyanthracene (manufactured by Kawasaki Kasei Co., Ltd.) in the dark, use a polytetrafluoroethylene filter with a pore size of 0.45 μm. The insoluble content was filtered to prepare a liquid crystal composition solution. This solution was applied onto a 75 μm thick polyethylene naphthalate film (Teonex Q-51, manufactured by Teijin Ltd.) whose surface was rubbed with a rayon cloth, using a spin coating method, and then dried on a hot plate at 60 ° C. It was. The liquid crystal composition layer on the obtained polyethylene naphthalate film was heated at 150 ° C. for 5 minutes and rapidly cooled to room temperature to obtain a liquid crystal composition layer.
Since the polyethylene naphthalate film used as the substrate has a large birefringence and is not preferable as an optical film, the obtained film is placed on the TAC film via an ultraviolet curable adhesive (UV-1394 manufactured by Toagosei Co., Ltd.). The film was transferred to obtain an optical film. That is, on the cured liquid crystal composition layer on the polyethylene naphthalate film, the adhesive UV-1394 was applied to a thickness of 5 mm, laminated with a TAC film, and 400 mj / cm ² from the TAC film side. After the ultraviolet light was irradiated to cure the adhesive, the polyethylene naphthalate film was peeled off.
When the obtained optical film was observed with a polarizing microscope, uniform cholesteric alignment of monodomains without disclination was observed. Moreover, when this film was seen from the front, it had selective reflection light peculiar to cholesteric, and when the transmission spectrum was evaluated by a spectroscope, a reduced region of transmitted light derived from selective reflection was found around 560 nm.

Claims (3)

An oxetane compound (A) having an optically active site represented by the following general formula (1), a side-chain liquid crystalline polymer substance (B) having an oxetanyl group, and a photocation generator and / or a thermal cation generator A polymerizable liquid crystal composition comprising the agent (C) and having a weight ratio of the compound (A): the polymer substance (B) in the range of 0.01: 99.99 to 60:40.
^{_{Z 1 - (CH 2) n}} -L 1 -P 1 -L 2 -C 1 -L 2 -P 1 -L 1 - (CH 2) n -Z 1 (1)
(In formula (1), Z ¹ represents any one of the following formulas (2) to (4), and L ¹ and L ² are each independently a single bond, —O—, —O—CO—, or Represents one of -CO-O- and P ¹
Represents the following formula (5) or (6), C ¹ represents an optically active site, and in formula (5), X represents a hydrogen atom, a methyl group or a halogen atom, and n represents an integer of 0 to 8. . )
The polymerizable liquid crystal composition according to claim 1, wherein the C ¹ in the general formula (1) of the is a group represented by the following general formula (7) or (8).
  3. A layer of the polymerizable liquid crystal composition according to claim 1 or 2 is formed on a film having orientation ability, molecules are cholesterically oriented to fix the orientation, and then polymerized by light and / or heat. Liquid crystal film obtained by letting