JP5331312B2 - Manufacturing method of optical anisotropic body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing an optically anisotropic body, in which inclination of an optical axis in a thickness direction is controlled, without using an optical alignment film which needs a large-scale UV irradiation apparatus. <P>SOLUTION: The method for manufacturing the optically anisotropic body comprises (1) a first step of forming an alignment film by applying a mixture of an alignment film material (A) for horizontally aligning a liquid crystal and an alignment film material (B) for vertically aligning the liquid crystal onto a substrate and subjecting the applied mixture of the alignment film materials (A), (B) to heating treatment and rubbing treatment and (2) a second step of applying a polymerizable liquid crystal material onto the formed alignment film, aligning the polymerizable liquid crystal material and polymerizing the aligned polymerizable liquid crystal material. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a method for producing an optical anisotropic body used for optical compensation of a liquid crystal display or the like.

  When a polymerizable liquid crystal material is used, various retardation films can be prepared. Among these, a film whose optical axis is inclined in the thickness direction is useful because it can be used for viewing angle compensation of a liquid crystal display (Non-Patent Document 1). In order to compensate the viewing angle using the retardation film, it is necessary to control the tilt angle of the optical axis in a wide range. In order to control the tilt of the optical axis in the retardation film, it is necessary to control the pretilt angle of the alignment film for aligning the polymerizable liquid crystal in the range of 0 to 90 °.

  In order to control the pretilt angle, a configuration using a photo-alignment film as an alignment film for aligning liquid crystal molecules is disclosed (Patent Document 1). However, in order to align liquid crystal molecules using the photo-alignment film, in many cases, it is necessary to irradiate the photo-alignment film with polarized ultraviolet rays, and there is a problem that a large-scale polarized ultraviolet irradiation apparatus is required.

As a method for controlling the pretilt angle without using a photo-alignment film, in a normal liquid crystal material having no polymerizability, an alignment film material appropriately mixed with a horizontal alignment film material and a vertical alignment film material is used. A technique for film / rubbing is disclosed (Non-Patent Document 2). However, the disclosure in the document relates to a normal liquid crystal material having a completely different manufacturing method, and there is no disclosure about application to a polymerizable liquid crystal material having completely different properties and structures from the normal liquid crystal material.
JP 10-123531 A P.van de Witte, S. Stalllinga, JAMM van Haaren, Digest of Internatinal Display Workshop '97, 395 (1997) Applied Physics Letter 88,051910 (2006)

  An object of the present invention is to provide a method for efficiently producing an optical anisotropic body in which the inclination of the optical axis in the thickness direction is controlled without using a photo-alignment film that requires a large-scale ultraviolet irradiation device. It is in.

  As a result of studying a method for efficiently controlling the pretilt angle of the polymerizable liquid crystal composition, the present inventors have found that an alignment film material for horizontally aligning liquid crystals and an alignment film material for vertically aligning liquid crystals. The inventors found that the pretilt angle can be controlled by changing the mixing ratio, and completed the production method of the present invention.

（式中、X ¹ は水素原子又はメチル基を表し、sは0〜18の整数を表し、ｓが0のときｔは0を表し、ｓが1以上のときtは0又は1を表し、A、B及びCはそれぞれ独立的に、1,4-フェニレン基、隣接しないCH基が窒素で置換された1,4-フェニレン基、1,4-シクロヘキシレン基、1つ又は隣接しない2つのCH ₂ 基が酸素若しくは硫黄原子で置換された1,4-シクロヘキシレン基、又は1,4-シクロヘキセニル基を表し、これらのA、B及びCは、さらに炭素原子数1〜7のアルキル基、アルコキシ基、アルカノイル基、シアノ基又はハロゲン原子で水素原子が一つ以上置換されていても良く、ｕは０、１、２又は３を表し、Y ^１ 及びY ^２ はそれぞれ独立的に単結合、-CH ₂ CH ₂ -、-CH ₂ O-、-OCH ₂ -、-COO-、-OCO-、-C≡C-、-CH=CH-、-CF=CF-、-(CH ₂ ) ₄ -、-CH ₂ CH ₂ CH ₂ O-、-OCH ₂ CH ₂ CH ₂ -、-CH=CH-CH ₂ CH ₂ -、-CH ₂ CH ₂ -CH=CH-、-CH=CH-COO-、-OCO-CH=CH-、-CH ₂ CH ₂ -COO-、-CH ₂ CH ₂ -OCO-、-COO-CH ₂ CH ₂ -又は-OCO-CH ₂ CH ₂ -を表し、Y ³ は単結合、-O-、-OCO-、-COO-、-CH=CH-COO-又は式（II）

（式中、X ^２ は水素原子又はメチル基を表し、vは0〜18の整数を表し、vが0のときwは0を表し、vが1以上のときwは0又は1を表す。)を表し、Z ¹ は水素原子、ハロゲン原子、シアノ基、炭素原子数1〜20の炭化水素基を表す。但しY ³ が式(II)を表すときは、Z ¹ は水素原子を表す。）で表される化合物を含有するものであり、
前記混合物中の前記配向膜材料（Ａ）と前記配向膜材料（Ｂ）の混合比を変更することにより、光学異方体のプレチルト角を制御することを特徴とする光学異方体の製造方法を提供する。 In the present invention, (1) a mixture of an alignment film material (A) for horizontally aligning liquid crystals and an alignment film material (B) for vertically aligning liquid crystals is applied to a substrate, and the applied alignment film materials (A) and (B The first step of forming an alignment film by subjecting the mixture to a heat treatment and a rubbing treatment, and (2) applying a polymerizable liquid crystal material on the formed alignment film to align the polymerizable liquid crystal material and aligning the polymerization A second step of polymerizing the conductive liquid crystal material,
The polymerizable liquid crystal material has the general formula (I)

(In the formula, X ¹ represents a hydrogen atom or a methyl group, s represents an integer of 0 to 18, t represents 0 when s is 0, t represents 0 or 1 when s is 1 or more, A, B and C are each independently 1,4-phenylene group, 1,4-phenylene group in which non-adjacent CH group is substituted with nitrogen, 1,4-cyclohexylene group, one or two non-adjacent CH ₂ represents a 1,4-cyclohexylene group substituted by an oxygen or sulfur atom, or a 1,4-cyclohexenyl group, and these A, B and C are further alkyl groups having 1 to 7 carbon atoms. , An alkoxy group, an alkanoyl group, a cyano group, or a halogen atom may be substituted with one or more hydrogen atoms, u represents 0, ¹ , 2, or 3, and Y ¹ and Y ² are each independently a single bond _{, -CH 2 CH 2 -, -} CH 2 O -, - OCH 2 -, - COO -, - OCO -, - C≡C -, - CH = CH -, - CF = CF -, - (CH 2) _{4 -, - CH 2 CH 2} CH 2 O -, - OCH 2 CH 2 CH 2 -, - CH = CH-CH 2 CH 2 -, -CH ₂ CH ₂ -CH = CH-, -CH = CH- COO-, -OCO -CH = CH-, -CH ₂ CH ₂ -COO-, -CH ₂ CH ₂ -OCO-, -COO-CH ₂ CH ₂ -or -OCO-CH ₂ CH _2- represents Y ³ is a single bond, -O-, -OCO-, -COO-, -CH = CH-COO- or formula (II)

(In the formula, X ² represents a hydrogen atom or a methyl group, v represents an integer of 0 to 18, w represents 0 when v is 0, and w represents 0 or 1 when v is 1 or more. Z ¹ represents a hydrogen atom, a halogen atom, a cyano group, or a hydrocarbon group having 1 to 20 carbon atoms. However, when Y ³ represents the formula (II), Z ¹ represents a hydrogen atom. ) Containing a compound represented by
A method for producing an optical anisotropic body, wherein a pretilt angle of the optical anisotropic body is controlled by changing a mixing ratio of the alignment film material (A) and the alignment film material (B) in the mixture. I will provide a.

  The production method of the present invention can efficiently produce an optical anisotropic body in which the inclination of the optical axis in the thickness direction is controlled by controlling the pretilt angle of the polymerizable liquid crystal composition. Since the manufacturing method of the present invention does not use a photo-alignment film for controlling the pretilt angle, a large-scale ultraviolet irradiation device is not required and the manufacturing efficiency is excellent.

The best mode of the method for producing an optical anisotropic body according to the present invention will be described below.
As the alignment film material (A) for horizontally aligning the liquid crystal used in the present invention, a polyimide alignment film material is preferable. Either the alignment film material that can be obtained by heating and baking after application to the substrate called polyamic acid type, or the type that does not require heating and baking after application to the substrate called soluble polyimide type, can be used. good. Specific examples of alignment film materials for horizontally aligning liquid crystals include AL-1051, AL-1254, AL16470, AL16301, AL3046, AL22620, AL23201 (above, manufactured by JSR Corporation), SE-410, SE-130, SE -2170, SE-150, SE-3310, SE-3210, SE-2811, SE-2911, SE-4310, SE-3140, SE-3510, SE-4210, SE-610, SE-7992, SE-7492 , SE-5291, SE8313, SE-8613, SE-1410, SE-8292, SE-4540, SE-6441 (above, manufactured by Nissan Chemical Industries, Ltd.).

  As the alignment film material (B) for vertically aligning the liquid crystal used in the present invention, a polyimide alignment film material is preferable. Either the alignment film material that can be obtained by heating and baking after application to the substrate called polyamic acid type, or the type that does not require heating and baking after application to the substrate called soluble polyimide type, can be used. good. Specific examples of alignment film materials for vertically aligning liquid crystals include AL61543, AL60601 (above, manufactured by JSR Corporation), SE-1211, SE-5300 (above, manufactured by Nissan Chemical Industries, Ltd.), and the like. .

  As a method of mixing the alignment film material (A) for horizontally aligning the liquid crystal and the alignment film material (B) for vertically aligning the liquid crystal, the alignment film material may be mixed in a state in which the alignment film material is dissolved in a solvent. A solid alignment film material (B) may be added to the alignment film material (A) dissolved in the solution, or a solid alignment film material may be added to the alignment film material (B) dissolved in the solvent. (A) may be added, and the solid alignment film material (A) and the solid alignment film material (B) may be added to the solvent. The higher the ratio of the alignment film material (A) in the alignment film material, the smaller the pretilt angle obtained. Both the alignment film material (A) and the alignment film material (B) do not necessarily need to be used alone, and a plurality of them may be mixed.

  As the substrate, an inorganic material such as a glass material, or an organic material such as polycycloolefin, triacetyl cellulose, or polycarbonate sold as Arton (manufactured by JSR Corporation) or ZEONOR (manufactured by Nippon Zeon Corporation) can be used. .

Examples of the method for applying the mixture of the alignment film material (A) and the alignment film material (B) to the substrate include spin coating, blade coating, and die coating.
After application, it is necessary to distill off the solvent from the mixture. Therefore, when baking to ensure the characteristics of the alignment film material is not necessary, for example, when using a soluble polyimide type alignment film material, the baking process is not performed. Do. As heating temperature, the range of 40-150 degreeC is preferable, and the range of 50-120 degreeC is still more preferable. The heating time is preferably 10 seconds to 30 minutes, more preferably 20 seconds to 10 minutes.

  When firing is necessary to ensure the properties of the alignment film material, for example, when a polyamic acid type alignment film material is used, a firing process is performed. In this case, the firing temperature is preferably 150 to 250 ° C, more preferably 180 to 240 ° C. The firing time is preferably in the range of 1 minute to 120 minutes, and more preferably in the range of 2 to 90 minutes. By the baking treatment at this time, the solvent contained in the mixture is also distilled off.

  After forming a film by applying a mixture of the alignment film material (A) and the alignment film material (B) to the substrate and firing as necessary, the first step is completed by performing a rubbing treatment. The rubbing process may be usually performed by an apparatus and conditions used in this technical field.

  In order to align the polymerizable liquid crystal material with the alignment film obtained in the first step, the polymerizable liquid crystal material is applied to the surface of the alignment film obtained in the first step, or the alignment obtained in the first step. There is a method in which two substrates with films are prepared, the alignment film surfaces are opposed to each other to maintain a certain distance, and a polymerizable liquid crystal material is sandwiched between the gaps. In the present invention, sandwiching the polymerizable liquid crystal material in this way is also referred to as “coating”.

  When a polymerizable liquid crystal material is applied, the polymerizable liquid crystal may be dissolved in an organic solvent. As the organic solvent, those that can dissolve the polymerizable liquid crystal material satisfactorily are preferable. Examples of such an organic solvent include toluene, xylene, cyclohexanone, cyclopentanone, propylene glycol monomethyl ether acetate, and the like. Examples of the method for applying the polymerizable liquid crystal include spin coating, blade coating, and die coating. After applying the solvent, it is preferable to heat in order to distill off the solvent. In order to obtain a uniform alignment state quickly, heating is preferable. The heating temperature is preferably in the range of 40 to 150 ° C, more preferably in the range of 50 to 120 ° C, and particularly preferably in the range of 60 to 110 ° C. The heating time is preferably 10 seconds to 30 minutes.

  When the polymerizable liquid crystal material is sandwiched between two substrates with an alignment film, the two substrates are preferably kept parallel and the gap is preferably maintained at 1 to 200 μm. Examples of a method for sandwiching the polymerizable liquid crystal material between two substrates include a method using a capillary phenomenon and a vacuum injection method. When injecting, the polymerizable liquid crystal material may be heated.

  The polymerizable liquid crystal material is a material in which a polymerizable functional group is added to a low molecular liquid crystal skeleton, and any material that is recognized as a polymerizable liquid crystal material in this technical field can be used without particular limitation. Examples of the polymerizable functional group include an acryloyloxy group, a methacryloyloxy group, a vinyl ether group, and an epoxy group. Among such polymerizable liquid crystal materials, the general formula (I)

(In the formula, X ¹ represents a hydrogen atom or a methyl group, s represents an integer of 0 to 18, t represents 0 when s is 0, t represents 0 or 1 when s is 1 or more, A, B and C are each independently 1,4-phenylene group, 1,4-phenylene group in which non-adjacent CH group is substituted with nitrogen, 1,4-cyclohexylene group, one or two non-adjacent CH ₂ represents a 1,4-cyclohexylene group substituted by an oxygen or sulfur atom, or a 1,4-cyclohexenyl group, and these A, B and C are further alkyl groups having 1 to 7 carbon atoms. , An alkoxy group, an alkanoyl group, a cyano group, or a halogen atom may be substituted with one or more hydrogen atoms, u represents 0, ¹ , 2, or 3, and Y ¹ and Y ² are each independently a single bond _{, -CH 2 CH 2 -, -} CH 2 O -, - OCH 2 -, - COO -, - OCO -, - C≡C -, - CH = CH -, - CF = CF -, - (CH 2) _{4 -, - CH 2 CH 2} CH 2 O -, - OCH 2 CH 2 CH 2 -, - CH = CH-CH 2 CH 2 -, -CH ₂ CH ₂ -CH = CH-, -CH = CH-COO-, -OCO-CH = CH-, -CH ₂ CH ₂ -COO-, -CH ₂ CH ₂ -OCO-, -COO-CH ₂ CH ₂ -or -OCO-CH ₂ CH _2- represents Y ³ is a single bond, -O-, -OCO-, -COO-, -CH = CH-COO- or formula (II)

(In the formula, X ² represents a hydrogen atom or a methyl group, v represents an integer of 0 to 18, w represents 0 when v is 0, and w represents 0 or 1 when v is 1 or more. Z ¹ represents a hydrogen atom, a halogen atom, a cyano group, or a hydrocarbon group having 1 to 20 carbon atoms. However, when Y ³ represents the formula (II), Z ¹ represents a hydrogen atom. )

It is preferable to contain the compound represented by these.
As an example of a specific compound, the compound represented by following formula (1)-(6) can be mentioned, for example.

(In formulas (1) to (6), s and v each independently represent an integer of 1 to 18, and Y ³ and Z ¹ represent the same meaning as in general formula (I).)

  A photopolymerization initiator can be added to the polymerizable liquid crystal material for the purpose of improving the polymerization reactivity. Examples of the photopolymerization initiator include benzoin ethers, benzophenones, acetophenones, benzyl ketals, and acylphosphine oxides. The addition amount is preferably 0.01 to 5% by mass, more preferably 0.02 to 1% by mass, and particularly preferably 0.03 to 1% by mass with respect to the polymerizable liquid crystal material.

  In addition, a stabilizer can be added to the polymerizable liquid crystal material in order to improve its storage stability. Examples of the stabilizer that can be used include hydroquinone, hydroquinone monoalkyl ethers, tert-butylcatechols, pyrogallols, thiophenols, nitro compounds, β-naphthylamines, β-naphthols, nitroso compounds, and the like. . When the stabilizer is used, the addition amount is preferably in the range of 0.005 to 1% by mass, more preferably 0.02 to 0.5% by mass, and 0.03 to 0.1% with respect to the polymerizable liquid crystal material. Mass% is particularly preferred.

As a method of polymerizing the polymerizable liquid crystal material, since rapid progress of polymerization is desirable, a method of polymerizing by irradiating active energy rays such as ultraviolet rays or electron beams is preferable. When polymerization is performed in a state where the liquid crystal composition is sandwiched between two substrates, at least the substrate on the irradiation surface side must be given appropriate transparency to the active energy rays. Moreover, it is preferable that the temperature at the time of irradiation is in the temperature range in which the liquid crystal state of the polymerizable liquid crystal material is maintained. In particular, in the case of producing a polymer by photopolymerization, the polymerization is carried out at a temperature as close to room temperature as possible from the viewpoint of avoiding unintentional induction of thermal polymerization, that is, typically at a temperature of 25 ° C. Is preferred. The intensity of the active energy ray is preferably 0.1 mW / cm ^{2 to 2} W / cm ² . When the strength is 0.1 mW / cm ² or less, a great amount of time is required to complete the photopolymerization, and the productivity may deteriorate. When the strength is 2 W / cm ² or more, the polymerizable liquid crystal material There is a risk of deterioration.

The polymer obtained by the polymerization can be subjected to a heat treatment for the purpose of reducing the initial characteristic change and achieving stable characteristic expression. The heat treatment temperature is preferably in the range of 50 to 250 ° C., and the heat treatment time is preferably in the range of 30 seconds to 12 hours.
The polymer produced by such a method may be peeled off from the substrate and used alone or without peeling. Further, the obtained polymer may be laminated or bonded to another substrate for use.

EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples.
(Experimental example 1)
A polymerizable liquid crystal material (A) comprising the following components was prepared. In addition, the numerical value described in the right end shows content (mass%) of each component in polymeric liquid crystal material (A).

This polymerizable liquid crystal material (A) exhibited a nematic liquid crystal phase at room temperature (25 ° C.). The nematic phase-isotropic liquid phase transition temperature was 52 ° C. Further, (refractive index of extraordinary light) n _e measured at 589nm in 1.664, n _o (refractive index of ordinary light) is 1.505, the birefringence index ([Delta] n) was 0.159. The viscosity was 178 mPa · s. A polymerizable liquid crystal material (A ′) comprising 99 parts by mass of the polymerizable liquid crystal composition (A) and 0.1 parts by mass of a photopolymerization initiator TPO (manufactured by Ciba Specialty Chemicals) was prepared.

Example 1
JASR9203 (alignment film material for horizontal alignment) manufactured by JSR Corporation and JALS2021 (alignment film material for vertical alignment) were mixed at a ratio of 90:10 (capacity ratio). This was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The two glass substrates with alignment films thus obtained were opposed so that the alignment film surfaces face each other. The gap was set to 2 μm. The polymerizable liquid crystal material (A ′) produced in Experimental Example 1 was injected into this gap. Two minutes after the completion of the injection, the polymerizable liquid crystal was cured by irradiating with 180 mJ / cm ² ultraviolet rays. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 33 degrees.

(Example 2)
JALS9203 (alignment film material for horizontal alignment) manufactured by JSR Corporation and JALS2021 (alignment film material for vertical alignment) were mixed at a ratio of 85:15 (capacity ratio). This was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The two glass substrates with alignment films thus obtained were opposed so that the alignment film surfaces face each other. The gap was set to 2 μm. The polymerizable liquid crystal material (A ′) produced in Experimental Example 1 was injected into this gap. Two minutes after the completion of the injection, the polymerizable liquid crystal was cured by irradiating with 180 mJ / cm ² ultraviolet rays. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 56 degrees.

(Example 3)
JALS9203 (alignment film material for horizontal alignment) manufactured by JSR Corporation and JALS2021 (alignment film material for vertical alignment) were mixed at a ratio of 80:20 (capacity ratio). This was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The two glass substrates with alignment films thus obtained were opposed so that the alignment film surfaces face each other. The gap was set to 2 μm. The polymerizable liquid crystal material (A ′) produced in Experimental Example 1 was injected into this gap. Two minutes after the completion of the injection, the polymerizable liquid crystal was cured by irradiating with 180 mJ / cm ² ultraviolet rays. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 64 degrees.

(Reference Example 1)
JALS9203 (alignment film material for horizontal alignment) manufactured by JSR Corporation was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The two glass substrates with alignment films thus obtained were opposed so that the alignment film surfaces face each other. The gap was set to 2 μm. The polymerizable liquid crystal material (A ′) produced in Experimental Example 1 was injected into this gap. Two minutes after the completion of the injection, the polymerizable liquid crystal was cured by irradiating with 180 mJ / cm ² ultraviolet rays. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 3 degrees.

(Reference Example 2)
JALS2021 (an alignment film material for vertical alignment) manufactured by JSR Corporation was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The two glass substrates with alignment films thus obtained were opposed so that the alignment film surfaces face each other. The gap was set to 2 μm. The polymerizable liquid crystal material (A ′) produced in Experimental Example 1 was injected into this gap. Two minutes after the completion of the injection, the polymerizable liquid crystal was cured by irradiating with 180 mJ / cm ² ultraviolet rays. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 89 degrees.

  The above results are shown in the table below. It can be seen that the tilt angle of the optical axis of the optical anisotropic body (film) could be controlled by changing the ratio of the horizontal alignment film material and the vertical alignment film material.

(Experimental example 2)
A polymerizable liquid crystal material (B) comprising the following components was prepared. In addition, the numerical value described in the right end shows content (mass%) of each component in polymeric liquid crystal material (B).

  To the polymerizable liquid crystal material (B), 5% by mass of polymerization initiator Irgacure-907 and 0.3% by mass of liquid paraffin were added, and toluene was added so that the solid content would be 30% by mass. ) Was prepared.

Example 4
JALS9203 (alignment film material for horizontal alignment) manufactured by JSR Corporation and JALS2021 (alignment film material for vertical alignment) were mixed at a ratio of 80:20 (capacity ratio). This was spin-coated (2000 rpm) on a glass substrate and then baked at 180 ° C. for 1 hour. Thereafter, a rubbing treatment was performed. The polymerizable liquid crystal material (B ′) prepared in Experimental Example 2 was spin-coated (3000 rpm) on the obtained glass substrate with an alignment film. The spin-coated substrate was heated at 60 ° C. for 1 minute to volatilize toluene, and then cooled to room temperature, and then irradiated with 420 mJ / cm ² of ultraviolet light in an argon atmosphere to cure the polymerizable liquid crystal. The pretilt angle (tilt angle of the optical axis of the film) of this cured film was measured by a crystal rotation method and found to be 30 degrees.

Claims (4)

(1) A mixture of alignment film material (A) for horizontally aligning liquid crystals and alignment film material (B) for vertically aligning liquid crystals is applied to a substrate, and the applied mixture of alignment film materials (A) and (B) is applied to the substrate. A first step of forming an alignment film by performing a heat treatment and a rubbing treatment; (2) applying a polymerizable liquid crystal material on the formed alignment film to align the polymerizable liquid crystal material; Having a second step of polymerizing,
The polymerizable liquid crystal material has the general formula (I)

(In the formula, X ¹ represents a hydrogen atom or a methyl group, s represents an integer of 0 to 18, t represents 0 when s is 0, t represents 0 or 1 when s is 1 or more, A, B and C are each independently 1,4-phenylene group, 1,4-phenylene group in which non-adjacent CH group is substituted with nitrogen, 1,4-cyclohexylene group, one or two non-adjacent CH ₂ represents a 1,4-cyclohexylene group substituted by an oxygen or sulfur atom, or a 1,4-cyclohexenyl group, and these A, B and C are further alkyl groups having 1 to 7 carbon atoms. , An alkoxy group, an alkanoyl group, a cyano group, or a halogen atom may be substituted with one or more hydrogen atoms, u represents 0, ¹ , 2, or 3, and Y ¹ and Y ² are each independently a single bond _{, -CH 2 CH 2 -, -} CH 2 O -, - OCH 2 -, - COO -, - OCO -, - C≡C -, - CH = CH -, - CF = CF -, - (CH 2) _{4 -, - CH 2 CH 2} CH 2 O -, - OCH 2 CH 2 CH 2 -, - CH = CH-CH 2 CH 2 -, -CH ₂ CH ₂ -CH = CH-, -CH = CH- COO-, -OCO -CH = CH-, -CH ₂ CH ₂ -COO-, -CH ₂ CH ₂ -OCO-, -COO-CH ₂ CH ₂ -or -OCO-CH ₂ CH _2- represents Y ³ is a single bond, -O-, -OCO-, -COO-, -CH = CH-COO- or formula (II)

(In the formula, X ² represents a hydrogen atom or a methyl group, v represents an integer of 0 to 18, w represents 0 when v is 0, and w represents 0 or 1 when v is 1 or more. Z ¹ represents a hydrogen atom, a halogen atom, a cyano group, or a hydrocarbon group having 1 to 20 carbon atoms. However, when Y ³ represents the formula (II), Z ¹ represents a hydrogen atom. ) Containing a compound represented by
A method for producing an optical anisotropic body, wherein a pretilt angle of the optical anisotropic body is controlled by changing a mixing ratio of the alignment film material (A) and the alignment film material (B) in the mixture. .   The polymerization is performed by irradiation with ultraviolet rays or electron beams, and the mixing ratio of the alignment film material (A) and the alignment film material (B) in the mixture is 90:10 to 80:20 (capacity ratio). Item 2. A method for producing an optical anisotropic body according to Item 1.   The method for producing an optical anisotropic body according to claim 1 or 2, wherein the alignment film material (A) for horizontally aligning the liquid crystal is a polyimide-based alignment film material.   The method for producing an optical anisotropic body according to any one of claims 1 to 3, wherein the alignment film material (B) for vertically aligning the liquid crystal is a polyimide-based alignment film material.