JP2004185028A - Liquid crystal composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical anisotropic film and a liquid crystal display element having little decrease in the transmittance and making bright display possible in a liquid crystal display element having an optical anisotropic film as constituent features. <P>SOLUTION: The optical anisotropic film has a polymerized layer consisting of a photopolymerized product of a polymerizable liquid crystal composition and having partially different optical retardations. The polymerizable liquid crystal composition contains a first monofunctional acrylate or a first monofunctional methacrylate which are respectively an acrylate or methacrylate of a cyclic alcohol or phenol having a liquid crystalline skeleton with at least two six-member rings as a partial structure, and the composition shows a liquid crystal phase at room temperature. Since the liquid crystal display element using the above optical anisotropic film develops colors by the combination with a polarizing film based on optical retardation, it shows little decrease in the transmittance and makes bright display compared to a liquid crystal display element which develops colors by using absorption of dyes or the like. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

The present invention relates to an optically anisotropic film, which is a photopolymer of a polymerizable liquid crystal composition and has a partially different optical retardation, and a liquid crystal display device having the optically anisotropic film.

  Current color liquid crystal display devices have a built-in backlight that consumes a large amount of power in order to obtain a bright display, and the amount of power consumption poses a problem when the color liquid crystal display device is mounted on portable equipment. ing. As a means for solving this, Nishino et al. Have proposed a reflective color liquid crystal display element which does not require a backlight and performs color display by using the birefringence of both a liquid crystal and a retardation film ( Non-Patent Document 1). However, according to this method, when the number of color arrangements is to be increased from the principle, a plurality of retardation films need to be laminated, which causes a problem that light transmittance is reduced and a bright display is hardly obtained.

Nikkei Microdevices, January 1994, p. 99

  The problem to be solved by the present invention is to provide an optically anisotropic film that enables color display without being limited by the balance between the number of colors and the transmittance, a method for manufacturing the same, and a liquid crystal display device using the optically anisotropic film. Is to provide.

  The present inventors have conducted intensive studies on means for solving the above-mentioned problems, and as a result, such a problem was found to be a retardation film in which a single optical sheet having a different optical phase difference for each portion corresponding to a pixel of a liquid crystal display element. The present invention has been found to be able to solve the problem by using a photographic film.

  That is, the present invention provides, as a first invention, a first monofunctional acrylate or a first monofunctional acrylate which is an acrylic acid or methacrylic acid ester of a cyclic alcohol or phenol having a liquid crystal skeleton having at least two 6-membered rings as a partial structure. An optically anisotropic film, which contains a monofunctional methacrylate, is a photopolymer of a polymerizable liquid crystal composition exhibiting a liquid crystal phase at room temperature, and has a polymer layer having a partially different optical retardation. As a second invention, a liquid crystal display device having the optically anisotropic film is provided.

  The optically anisotropic film of the present invention develops a color based on its optical retardation in combination with a polarizing film and can be used as a color filter for a liquid crystal display device. Further, since the optical phase difference is different for each pixel, the number of colors can be increased without laminating a retardation film. In addition, since the liquid crystal display device using this optically anisotropic film develops a color in combination with a polarizing film based on the optical phase difference, light transmission is higher than that of a liquid crystal display device that generates color using absorption of a dye or the like. The rate of reduction is small and a bright display is obtained.

  First, the optically anisotropic film of the first invention will be described in detail. The optically anisotropic film of the present invention is a photopolymer of a polymerized liquid crystal composition, and has a polymer layer having a partially different optical retardation.

  The polymerizable liquid crystal composition used in the present invention includes a liquid crystal having at least two 6-membered rings in order to avoid unintended thermal polymerization during photopolymerization in a liquid crystal state and to fix a uniform alignment state. A first monofunctional acrylate or a first monofunctional methacrylate, which is an acrylic acid or methacrylic acid ester of a cyclic alcohol or phenol or an aromatic hydroxy compound having a functional skeleton as a partial structure, and exhibits a liquid crystal phase. It is preferable to use a polymerizable liquid crystal composition. Such a monofunctional acrylate or a monofunctional methacrylate may be a monofunctional acrylate or a monofunctional methacrylate having a liquid crystal skeleton as a partial structure, for example, of the general formula (I)

（式中、Ｘは水素原子又はメチル基を表わし、６員環Ａ、Ｂ及びＣはそれぞれ独立的に、

(Wherein X represents a hydrogen atom or a methyl group, and the 6-membered rings A, B and C each independently represent

And n represents an integer of 0 or 1, m represents an integer of 1 to 4, Y ¹ and Y ² each independently represent 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 ₂ ＣＨCHCH ₂ CH ₂ — or —CH ₂ CH ₂ CH ＝ CH—, Y ³ represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 20 carbon atoms, Represents an alkoxy group, an alkenyl group or an alkenyloxy group. )). Among them, particularly, in the above general formula (I), the 6-membered rings A, B and C are each independently

を表わし、ｍは１又は２の整数を表わし、Ｙ¹及びＹ²はそれぞれ独立的に、単結合又は−Ｃ≡Ｃ−を表わし、Ｙ³はハロゲン原子、シアノ基、炭素原子数１〜２０のアルキル基又はアルコキシ基を表わす化合物が好ましい。

And m represents an integer of 1 or 2, Y ¹ and Y ² each independently represent a single bond or —C≡C—, and Y ³ represents a halogen atom, a cyano group, or a carbon atom having 1 to 20 carbon atoms. The compound which represents an alkyl group or an alkoxy group is preferred.

  Representative examples of such compounds and their phase transition temperatures are shown, but the monofunctional acrylate or methacrylate compounds that can be used in the present invention are not limited to these compounds.

(In the above, the cyclohexane ring represents a transcyclohexane ring, and in the phase transition temperature scheme, C represents a crystal phase, N represents a nematic phase, S represents a smectic phase, and I represents an isotropic liquid phase. In addition, a second monofunctional acrylate or a second monofunctional methacrylate compound having a liquid crystal skeleton known as a partial structure as a partial structure is added to the polymerizable liquid crystal composition used in the present invention. May be. At this time, the resulting polymerizable liquid crystal composition desirably exhibits an enantiomeric nematic liquid crystal phase at room temperature. Examples of the monofunctional acrylate or monofunctional methacrylate that can be used here include, for example, those represented by the general formula (II)

（式中、Ｒは水素原子又はメチル基を表わし、ｐは２〜１２の整数を表わし、Ｙ⁴は単結合又は−ＣＯＯ−を表わし、Ｙ⁵はシアノ基、炭素原子数１〜６のアルキル基、アルコキシ基又はフェニル基を表す。）で表わされる化合物を挙げることができ、具体的には以下の化合物を挙げることができる。

(Wherein, R represents a hydrogen atom or a methyl group, p represents an integer of 2 to 12, Y ⁴ represents a single bond or —COO—, Y ⁵ represents a cyano group, an alkyl having 1 to 6 carbon atoms. Group, an alkoxy group or a phenyl group). Specific examples thereof include the following compounds.

(Wherein, R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group, j, k and l each independently represent an integer of 2 to 12, and R ⁴ represents a carbon atom In this manner, the polymerizable liquid crystal composition used in the present invention may contain only the first monofunctional (meth) acrylate, or may contain the second or third alkyl group or phenyl group. May be contained alone, or the first and second monofunctional (meth) acrylates may be used in combination.

  When the first and second monofunctional (meth) acrylates are used in combination as the polymerizable composition, the content of the second monofunctional (meth) acrylate is 50% based on the first monofunctional (meth) acrylate. It is preferable that the content is not more than weight%. This is because as the content of the second monofunctional (meth) acrylate increases, the mechanical strength and heat resistance of the obtained optically anisotropic film tend to be inferior.

  In the case of partially controlling the alignment state of the polymerizable liquid crystal composition by an electric field during the production of the optically anisotropic film, the polymerizable liquid crystal composition preferably has a positive dielectric anisotropy, It is particularly preferable that the anisotropy Δε of the ratio is 0.5 or more. In order to obtain such a polymerizable liquid crystal composition, it is preferable to include first and second monofunctional (meth) acrylates having a cyano group.

  Further, a liquid crystal compound having no polymerizable functional group may be added to the polymerizable liquid crystal composition used in the present invention in a range where the total amount in the polymerizable liquid crystal composition does not exceed 10% by weight. As the liquid crystal compound having no polymerizable functional group, a nematic liquid crystal compound, a smectic liquid crystal compound, a cholesteric liquid crystal compound and the like can be used without particular limitation as long as they are generally recognized as liquid crystals in this technical field. However, as the added amount increases, the mechanical strength of the obtained optically anisotropic film tends to decrease. Therefore, it is necessary to appropriately adjust the added amount.

  In addition, a compound having a polymerizable functional group but not exhibiting liquid crystallinity can be added. As such a compound, any compound which is generally recognized as a polymer-forming monomer or a polymer-forming oligomer in this technical field may be used, and an acrylate compound is particularly preferable.

  These liquid crystal compounds or polymerizable compounds may be appropriately selected and added in combination.However, at least the amount of each component added may be adjusted so that the liquid crystallinity of the obtained polymerizable liquid crystal composition is not lost. is necessary.

  Further, a photopolymerization initiator or a sensitizer may be added to the polymerizable liquid crystal composition used in the present invention for the purpose of improving the polymerization reactivity. Here, examples of the photopolymerization initiator that can be used include known benzoin ethers, benzophenones, acetophenones, and benzyl ketals. The addition amount is preferably 10% by weight or less, particularly preferably 5% by weight or less, based on the polymerizable liquid crystal composition.

  Further, a stabilizer may be added to the polymerizable liquid crystal composition used in the present invention in order to improve the storage stability. Examples of the stabilizer that can be used here include known hydroquinone, hydroquinone monoalkyl ethers, and tert-butylcatechol. The amount of the stabilizer is preferably 0.05% by weight or less. Furthermore, an optically active compound may be added to the polymerizable liquid crystal composition used in the present invention for the purpose of introducing a helical structure such as twisted nematic alignment or cholesteric alignment. The optically active compound that can be used here need not itself exhibit liquid crystallinity, and may or may not have a polymerizable functional group. The direction of the twist can be appropriately selected according to the purpose of use. Such optically active compounds include, for example, cholesteryl pelargonic acid having a cholesteryl group as an optically active group, cholesterol stearate, and “CB-15” and “C-15” having a 2-methylbutyl group as an optically active group (or more) BDH), "S-1082" (Merck), "CM-19", "CM-20", "CM" (all from Chisso), and "1-methylheptyl group having an optically active group" S-811 "(manufactured by Merck)," CM-21 ", and" CM-22 "(all manufactured by Chisso).

  Further, the optical phase difference (retardation) of the optically anisotropic film of the present invention takes different values depending on the portion corresponding to the pixel, and the value is preferably in the range of 0 to 1.8 μm, more preferably. It ranges from 0 to 1.2 microns. The shape and size of the portion corresponding to the pixel that takes uniform retardation can be set completely freely, from a small pixel of a quadrilateral with a side of about 60 microns to a circle or a triangle having a size of about several tens of centimeters. It is preferable to select a pattern such as a pattern or the like as appropriate according to the application.

  The thickness of the polymer layer in the optically anisotropic film of the present invention is preferably in the range of 0.1 to 100 microns, and particularly preferably in the range of 0.5 to 50 microns. In addition, the optically anisotropic film of the present invention may be a polymer layer alone as described above, and the polymer layer is carried on a transparent substrate, or is sandwiched between two transparent substrates. It may be. Further, those obtained by transferring the polymerized layer to the third transparent substrate can be used in the same manner.

  For the purpose of protecting the surface of the optically anisotropic film of the present invention, a protective layer may be formed on the surface of the optically anisotropic film using a thermosetting or photocurable resin. Furthermore, by forming a transparent electrode such as ITO on the surface of the optically anisotropic film of the present invention, this optically anisotropic film can be used as a component of a liquid crystal cell. In this case, in order to avoid damage to the optically anisotropic film due to heat or the like at the time of forming the ITO electrode, it is preferable to form a protective layer of a thermosetting or photocurable resin having heat resistance on the surface of the optically anisotropic film. preferable.

Next, a method for producing the optically anisotropic film according to the second invention will be described in detail. The optically anisotropic film of the present invention controls the applied voltage for each portion corresponding to the pixel of the liquid crystal display element to change the orientation state of the polymerizable liquid crystal composition, and in this state, the polymerizable liquid crystal composition is exposed to ultraviolet light or electrons. It can be manufactured by fixing the alignment state by irradiating an energy ray such as a ray. As such a manufacturing method, the present invention particularly provides the following three manufacturing methods.
(Manufacturing method 1)
(1) a first step of interposing a polymerizable liquid crystal composition between an alignment-processed first transparent substrate having an electrode layer and an alignment-processed second substrate having an electrode layer; (2) A second step of irradiating light from the side of the first transparent substrate while controlling an applied voltage for each pixel between the two substrates, and (3) peeling off the first transparent substrate and the second substrate 3rd process (manufacturing method 2)
(1) a first step of interposing a polymerizable liquid crystal composition between an alignment-processed first transparent substrate having an electrode layer and an alignment-processed second substrate having an electrode layer; A second step of irradiating light from the side of the first transparent substrate while controlling an applied voltage for each pixel between the two substrates, and (3) a third step of peeling the second substrate (manufacturing method 3 )
(1) A first step of interposing a polymerizable liquid crystal composition between two alignment-treated transparent substrates having an electrode layer (2) While controlling an applied voltage for each pixel between the two substrates, And a method for producing an optically anisotropic film having a second step of irradiating light.

  Further, in addition to the above-described production method of the present invention, as a method for obtaining a different alignment state by applying a voltage, a polymerizable liquid crystal composition is sandwiched between two alignment-treated substrates having an electrode layer. After covering the upper surface of the substrate with a mask that allows energy rays to pass only to the portion corresponding to the desired pixel, irradiating the energy rays while applying a predetermined voltage, and fixing the alignment state by the predetermined voltage, the mask is further applied. In the same manner, for the part where the energy ray has not been irradiated, the energy ray is irradiated while applying the voltage changed by the part corresponding to the pixel, whereby the different alignment states are fixed by the predetermined voltage. There is also a method of manufacturing an optically anisotropic film.

  The method for producing the optically anisotropic film of the present invention will be described in more detail. According to the present invention, in (Production Method 1) and (Production Method 2), an alignment-processed first transparent substrate having an electrode layer and an alignment-processed second substrate having an electrode layer are manufactured by (manufacturing). In method 3), two alignment-treated transparent substrates having an electrode layer are arranged so that a voltage can be applied, and the polymerizable liquid crystal composition is interposed between the two substrates.

A substrate having an electrode layer is required as a transparent substrate used at this time. Specific examples include a glass substrate with ITO and a plastic substrate with ITO. Further, it is preferable to perform an alignment treatment on these substrates. Examples of the orientation treatment include a rubbing treatment in which the substrate surface is rubbed with a cloth or the like, an oblique vapor deposition method of SiO ₂ , and the like. In particular, a rubbing treatment method is preferred because of its simplicity. When the proper orientation cannot be obtained by rubbing the substrate surface with a cloth or the like, an organic thin film such as a polyimide thin film or a polyvinyl alcohol thin film is formed on the substrate surface according to a known method, and this is rubbed with a cloth or the like. Is also good.

  Next, light is irradiated from the transparent substrate side while controlling the applied voltage for each pixel of the two substrates. As a means for applying a voltage between the electrode layers, a static driving method or a time-division driving method used for an ordinary liquid crystal display element can be used, and a preferable applied voltage is a dielectric anisotropy of the polymerizable liquid crystal composition or a voltage between the substrates. Although it is appropriately adjusted depending on the distance, an AC voltage of 0.5 V or more is preferable.

  In addition, as a method of changing the alignment state of the polymerizable liquid crystal composition for each part corresponding to the pixel of the liquid crystal display element, after sandwiching the polymerizable liquid crystal composition between two substrates, the upper surface of the substrate is A mask that transmits energy rays is covered only on the part corresponding to the desired pixel, and the polymerizable liquid crystal composition is irradiated with energy rays while aligning the polymerizable liquid crystal composition with a magnetic field having an arbitrary direction and strength to fix the alignment state by the magnetic field. The optical anisotropic film in which the different alignment states are fixed in the portions corresponding to the pixels by irradiating the energy beams while changing the strength and direction of the magnetic field in the same manner in the portion where the energy beam has not been irradiated. Can be manufactured.

  When the orientation of the polymerizable liquid crystal composition is fixed by applying a magnetic field, it is not necessary to provide an electrode layer on the substrate, and the substrate can be used regardless of an organic material or an inorganic material. Specific examples of organic materials include, for example, polyethylene terephthalate, polycarbonate, polyimide, polymethyl methacrylate, polystyrene, polyethylene, polyvinyl chloride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyarylate, polysulfone, and cellulose. , Polyetheretherketone, and inorganic materials such as silicon and glass.

  Furthermore, the alignment structure of the polymerizable liquid crystal composition in a portion where an external field such as an electric field or a magnetic field is not applied depends on the alignment treatment of the substrate and the concentration of the optically active compound in the polymerizable liquid crystal composition. As the orientation structure, it is preferable to select an appropriate orientation state according to the use of the optically anisotropic film, and specific examples include the following orientation structures.

  The twisted nematic alignment having a twist angle of 90 degrees or less is achieved by, for example, arranging two rubbed substrates so as to face each other at a fixed interval so that the respective rubbing directions form a desired twist angle. It can be obtained by pinching things.

  The chiral nematic alignment or the cholesteric alignment can be obtained, for example, by facing two substrates at which horizontal alignment can be obtained at a certain interval, and sandwiching a polymerizable liquid crystal composition having a adjusted helical pitch (P) therebetween. . Further, it can also be obtained by supporting a polymerizable liquid crystal composition having a controlled helical pitch (P) on a single substrate capable of obtaining horizontal alignment at a constant thickness.

  Further, as described above, when the polymerizable liquid crystal composition does not contain an optically active compound, the alignment state of the optically anisotropic film depends on the alignment treatment of the substrate. It is preferable to select an appropriate orientation state depending on the type, and specific examples include the following orientation structures.

  Homeotropic alignment can be obtained, for example, by making two substrates capable of obtaining vertical alignment face each other at a certain interval, and sandwiching the polymerizable liquid crystal composition therebetween.

  Homogeneous alignment is performed, for example, by arranging two rubbed substrates facing each other at a constant interval so that the rubbing directions form an angle of 0 or 180 degrees, and sandwiching the polymerizable liquid crystal composition therebetween. Obtainable.

  Hybrid alignment in which the polymerizable liquid crystal composition layer continuously changes from vertical alignment to horizontal alignment in the thickness direction of the polymerizable liquid crystal composition layer, for example, a rubbed substrate and a substrate capable of obtaining vertical alignment are opposed at a certain interval, and the polymerizable liquid crystal is interposed therebetween. It can be obtained by sandwiching the composition.

  As described above, the alignment state of the polymerizable liquid crystal composition can be partially changed by a combination of the alignment by an external field such as an electric field or a magnetic field and the alignment treatment of the substrate. The photopolymerization is preferably performed by irradiating the polymerizable liquid crystal composition carried between the two substrates with an energy beam such as an ultraviolet ray or an electron beam. Transparency must be given. The temperature at the time of the polymerization must be a temperature at which the liquid crystal state of the polymerizable liquid crystal composition is maintained, but it is preferable to carry out the polymerization at a temperature close to room temperature in order to avoid unintended thermal polymerization.

  As described above, when photopolymerization is performed by sandwiching the polymerizable liquid crystal composition between two substrates, at least the substrate on the irradiation surface side must have appropriate transparency.

  Next, according to the purpose of use, one or two of the substrates used at the time of manufacture are peeled off as described above. At this time, in order to easily peel the substrate, it is preferable to form a thin film of an organic material or the like on the surface of the substrate in advance in order to impart good peelability to the substrate. Examples of such an organic material include a fluorinated polymer such as polytetrafluoroethylene, a mixture of polyvinyl alcohol and a diol compound such as 1,8-octanediol, and lecithin.

  According to the production method as described above, the optically anisotropic film of the present invention having the polymer layer in which differently oriented structures are partially fixed can be obtained. Next, the liquid crystal display device of the third invention will be described in detail. The liquid crystal display device of the present invention has the optical anisotropic film of the first invention. As the optically anisotropic film that can be used in the liquid crystal display device of the present invention, a polymer layer is sandwiched between two transparent substrates used in the production, and a polymer is formed on one transparent substrate. In a state where only the polymer layer carrying the polymer layer is transferred, or in a state where the polymer layer is transferred to the third transparent substrate after at least one substrate is peeled off. Further, as the liquid crystal display element of the present invention, a twisted nematic type, a super twisted nematic type, a phase transition type, a guest-host type, a ferroelectric liquid crystal display element can be used, and a liquid crystal having a polymer dispersed type dimming layer can be used. Display elements such as NCAP and PDLC can also be used. Further, a polymer network type liquid crystal display element (PN-LCD), which has a three-dimensional network structure of a transparent solid substance as a light control layer, has a low driving voltage and can be suitably used. It is preferable to appropriately select a driving method of these liquid crystal display elements depending on the type of the liquid crystal display element. However, a twisted nematic type or a polymer dispersed type is driven using an active element such as a TFT (thin film transistor) type. It is preferable in terms of display capacity.

  The structure of the liquid crystal display device of the present invention will be described below. The liquid crystal display device of the present invention has an optically anisotropic film as described above, and this optically anisotropic film is usually disposed between a polarizing plate and a liquid crystal cell, but has an electrode layer as described above. The optically anisotropic film can be used by being arranged in a liquid crystal cell.

  In the liquid crystal display device of the present invention, one of the two polarizing plates can be replaced with a reflector, and when a reflector is used, one electrode surface of the liquid crystal display device functions as a reflector. It is also preferable to combine them also because the parallax of the liquid crystal display element is improved.

  The angle between the polarization axis of the polarizing plate and the optical axis of the optically anisotropic film of the present invention is appropriately adjusted depending on the liquid crystal display device to be constituted, but it is generally preferable to arrange them so as to form an angle of 45 degrees. When two polarizing plates are used, it is preferable to arrange the polarizing axes of the two polarizing plates so as to be parallel or orthogonal to each other from the viewpoint of contrast.

  The liquid crystal display device of the present invention may be used by adding a commonly used micro color filter in order to improve the color purity of color development based on the optical phase difference.

Hereinafter, examples of the present invention will be shown, and the present invention will be described more specifically. However, the invention is not limited to these examples.
(Example 1)
Equation (a)

47.5 parts by weight of the compound of formula (d)

47.5 parts by weight of a compound of the formula (g)

A polymerizable liquid crystal composition (A) consisting of 5 parts by weight of the compound (A) was prepared. The obtained composition showed an enantiomeric nematic phase at room temperature (25 ° C.), and the transition temperature from the nematic phase to the isotropic liquid phase was 52 ° C. The ne (extraordinary refractive index) at 1.degree. C. was 1.67, the no (ordinary refractive index) was 1.51, and the dielectric anisotropy was +0.7 at 25.degree. A polymerizable liquid crystal composition (B) comprising 1 part by weight of a photopolymerization initiator "IRG-651" (manufactured by Ciba Geigy) in 99 parts by weight of the polymerizable liquid crystal composition (A) was obtained.
Next, 3.0 g of polyvinyl alcohol (degree of polymerization: about 500) and 3.0 g of 1,8-octanediol are dissolved in a mixed solvent consisting of 100 g of water and 100 g of ethanol to prepare a solution of the composition for a liquid crystal alignment treatment agent. did. This solution was spin-coated on a glass substrate (i) having a size of 25 mm × 30 mm as shown in FIG. 1 and having electrode layers (A), (B) and (C) as ITO transparent electrode layers. The solvent was almost dried in this spin coating. At this time, 1,8-octanediol was deposited on the glass substrate, and a uniform film was not obtained. Next, this glass substrate was heated at 110 ° C. for 5 minutes, and then cooled to room temperature, to obtain a uniform film without precipitation of 1,8-octanediol. This was rubbed in the direction shown in FIG. 1 to produce an oriented glass substrate (i-R).

Next, as shown in FIG. 2, a polyimide alignment treatment agent “AL-1254” (Nippon Synthetic Rubber Co., Ltd.) was applied on a glass substrate (ii) having the same size as the glass substrate (i) and having an ITO transparent electrode layer on the entire surface of the substrate. Co., Ltd.) was spin-coated. The substrate was kept at 180 ° C. for 80 minutes to form a polyimide film on the substrate. This polyimide film was rubbed in the direction shown in FIG. 2 to produce an oriented glass substrate (ii-R). The glass substrate (ii-R) and the rubbed surface of the glass substrate (ii-R) were opposed to each other, and the polymerizable liquid crystal composition (B) was sandwiched between them. At this time, the distance between the glass substrates was set to 9 microns, and the angle between the rubbing directions was set to 180 degrees. When the polymerizable liquid crystal composition sandwiched between two glass substrates was observed between two orthogonal polarizing plates, it was confirmed that uniform uniaxial alignment (homogeneous alignment) was obtained. Next, 4.1 Vrms between the electrode layer (A) and the counter electrode of the glass substrate (iR), 2.9 Vrms between the electrode layer (B) and the counter electrode, and 3 Vrms between the electrode layer (C) and the counter electrode. A sine wave having a frequency of 1 kHz and a voltage of 0.3 Vrms was applied. While applying a voltage to the polymerizable liquid crystal composition, the polymerizable liquid crystal composition is irradiated with ultraviolet light of 160 mJ / cm 2 at room temperature using an ultraviolet lamp (UVGL-25, manufactured by UVP) to emit light. Polymerization was performed to obtain an optically anisotropic film sandwiched between two glass substrates. This was kept at 150 ° C. for 5 minutes and then cooled at room temperature. After cooling to room temperature, the glass substrate (i-R) was peeled off from the optically anisotropic film to obtain an optically anisotropic film supported on the glass substrate (ii-R). An interference color was observed between the two orthogonal polarizing plates of the optically anisotropic film so that the angle between the optical axis (rubbing direction) of the optically anisotropic film and the polarizing axis of the polarizing plate was 45 degrees. And the results as shown in FIG. 3 were obtained. The interference color of the portion in contact with the electrode layer (A) is red, the interference color of the portion in contact with the electrode layer (B) is green, the interference color of the portion in contact with the electrode layer (C) is blue, and the other. The part exhibited a yellowish green color and a uniform interference color on partially different electrode layers of one optically anisotropic film. Therefore, it is clear that an optically anisotropic film having a partially different optical phase difference corresponding to each pixel was obtained. Even when the optically anisotropic film was kept at a temperature of 150 ° C., the uniform interference color did not change and there was no problem with heat resistance.

Example 2 As shown in FIG. 4, a glass substrate (iii) having a size of 25 mm × 30 mm and having electrode layers (A ′), (B ′) and (C ′) as ITO transparent electrode layers was subjected to polyimide alignment treatment. The agent “AL-1254” was spin-coated. This substrate was kept at 180 ° C. for 80 minutes to form a polyimide film on the glass substrate. This polyimide film was rubbed in the direction shown in FIG. 4 to produce an oriented glass substrate (iii-R). Next, as shown in FIG. 5, a polyimide alignment treatment agent “AL-1254” is spin-coated on a glass substrate (iv) having the same size as the glass substrate (iii) and having an ITO transparent electrode layer on the entire surface of the substrate. did. This substrate was kept at 180 ° C. for 80 minutes to form a polyimide film on a glass substrate. This polyimide film was rubbed in the direction shown in FIG. 5 to produce an oriented glass substrate (iv-R). The rubbed surface of the glass substrate (iii-R) and the rubbed surface of the glass substrate (iv-R) are opposed to each other, and the surface of the glass substrate (iv-R) having the anisotropy of the refractive index is opposed therebetween. A nematic liquid crystal composition "PN-019" (manufactured by Roddick) having 0.189 and a dielectric anisotropy of 7.2 was sandwiched. At this time, the distance between the glass substrates was set to 5.3 μm, and the angle between the rubbing directions was set to 90 °, thereby producing a twisted nematic liquid crystal cell. The optically anisotropic film produced in Example 1 was overlaid on this twisted nematic liquid crystal cell, and this was disposed between two polarizing films whose polarization axes were parallel to each other. At this time, the polarization axes of the two polarizing films were made to form an angle of 45 degrees with the optical axis (rubbing direction) of the optically anisotropic film. The rubbing direction of each of the two substrates constituting the twisted nematic liquid crystal cell is parallel or perpendicular to the polarization axis of the polarizing film, and the optically anisotropic film is formed on the electrode layer (A ') of the liquid crystal cell. The red portion of the interference color overlaps with the electrode layer (B ') of the liquid crystal cell, and the green portion of the interference color of the optically anisotropic film overlaps with the electrode layer (C') of the liquid crystal cell. The liquid crystal cell and the optically anisotropic anisotropic film were overlapped so that the blue portions of the interference film overlapped each other. When no voltage is applied, the liquid crystal display element manufactured in this manner has a red portion in the electrode layer (A ′), a green portion in the electrode layer (B ′), and a blue portion in the electrode layer (C ′). Vivid color development was obtained. By applying a voltage, a vivid color was obtained in which the electrode layer (A ') was green, the electrode layer (B') was red, and the electrode layer (C ') was yellow.

(Example 3) 80 parts by weight of the nematic liquid crystal composition "PN-019" used in Example 2, and caprolactone-modified neopentylglycylicol dihydroxypivalate diacrylate "HX-220" (manufactured by Nippon Kayaku Co., Ltd.) Polymerizable composition comprising 6 parts by weight, 6 parts by weight of lauryl acrylate “LA” (manufactured by Kyoeisha Yushi Kagaku Kogyo KK), and 0.4 parts by weight of photopolymerization initiator “IRG-651” (manufactured by Ciba Geigy) C) was prepared. Next, a glass substrate (v) having a size of 25 mm × 30 mm and having electrode layers (A ″), (B ″), and (C ″) as ITO transparent electrode layers as shown in FIG. As shown in FIG. 7, a glass substrate (vi) having the same size as the glass substrate (v) and having an ITO transparent electrode layer on the whole surface of the substrate is prepared, and the electrode layer surfaces of the glass substrate (v) and the glass substrate (vi) are prepared. The polymerizable composition (C) thus prepared was sandwiched between them. At this time, the interval between the glass substrates was set to be 12 microns. The polymerizable composition sandwiched between the two substrates is irradiated with an ultraviolet ray having an energy equivalent to 500 mJ / cm2 using a metal halide lamp of 80 W to polymerize the polymerizable composition, thereby causing a gap between the two substrates. A liquid crystal cell having a light modulating layer made of a transparent solid substance and a liquid crystal material was manufactured. The optically anisotropic film produced in Example 1 was overlaid on this liquid crystal cell, and this was disposed between two polarizing films whose polarization axes were orthogonal to each other. At this time, the optical axis (rubbing direction) of the optically anisotropic film was set at an angle of 45 degrees with respect to the polarization axis of the polarizing film. The interference color of the optically anisotropic film of red overlaps with the electrode layer (A ″) of the liquid crystal cell, and the interference color of the optically anisotropic film of green overlaps with the electrode layer (B ″) of the liquid crystal cell. The liquid crystal cell and the optically anisotropic film were overlapped so that the portions overlapped and the portion of the optically anisotropic film having a blue interference color overlapped with the electrode layer (C ″) of the liquid crystal cell. In the manufactured liquid crystal display element, when no voltage was applied, the display of the electrode layers (A ″), (B ″), and (C ″) was opaque (white). By applying a voltage, a vivid color was obtained in the electrode layer (A "), green in the electrode layer (B"), and blue in the electrode layer (C ").

FIG. 3 is a view showing a glass substrate (i) used in Example 1. FIG. 3 is a view showing a glass substrate (ii) used in Example 1. FIG. 3 is a view showing the observation result of the color filter for a liquid crystal display element of the present invention in Example 1. FIG. 9 is a view showing a glass substrate (iii) used in Example 2. FIG. 9 is a view showing a glass substrate (iv) used in Example 2. FIG. 9 is a view showing a glass substrate (v) used in Example 3. FIG. 9 is a view showing a glass substrate (vi) used in Example 3.

Claims (10)

A first monofunctional acrylate or a first monofunctional methacrylate, which is an acrylic acid or methacrylic acid ester of a cyclic alcohol or phenol having a liquid crystal skeleton having at least two 6-membered rings as a partial structure, and contains a liquid crystal phase at room temperature. An optically anisotropic film, which is a photopolymerized product of the polymerizable liquid crystal composition shown in (1) and which has a polymerized layer having a partially different optical retardation. The first monofunctional acrylate or the first monofunctional methacrylate has the general formula (I)

(Wherein X represents a hydrogen atom or a methyl group, and the 6-membered rings A, B and C each independently represent

And n represents an integer of 0 or 1, m represents an integer of 1 to 4, Y ¹ and Y ² each independently represent 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 ₂ ＣＨCHCH ₂ CH ₂ — or —CH ₂ CH ₂ CH ＝ CH—, wherein Y ³ is a hydrogen atom, a halogen atom, a cyano group, or an alkyl having 1 to 20 carbon atoms. Represents a group, an alkoxy group, an alkenyl group or an alkenyloxy group. The optically anisotropic film of claim 1, wherein the) is a compound represented by. In the general formula (I), the six-membered rings A, B, and C are each independently

And m represents an integer of 1 or 2, Y ¹ and Y ² each independently represent a single bond or —C≡C—, and Y 3 represents a halogen atom, a cyano group, or a C 1-20 carbon atom. The optically anisotropic film according to claim 2, which represents an alkyl group or an alkoxy group. 4. The optically anisotropic film according to claim 2, wherein the polymerizable liquid crystal composition contains a second monofunctional acrylate or a second monofunctional methacrylate having a liquid crystal skeleton as a partial structure. The second monofunctional acrylate or the second monofunctional methacrylate has the general formula (II)

(Wherein, R represents a hydrogen atom or a methyl group, p represents an integer of 2 to 12, Y ⁴ represents a single bond or —COO—, Y ⁵ represents a cyano group, or an alkyl having 1 to 6 carbon atoms. The optically anisotropic film according to claim 4, wherein the optically anisotropic film is represented by a group, an alkoxy group or a phenyl group. The optically anisotropic film according to claim 5 , wherein the polymerizable liquid crystal composition exhibits an enantiomeric nematic liquid crystal phase at room temperature. The optically anisotropic film according to claim 2, comprising a transparent substrate and the polymer layer. A liquid crystal display device comprising an optical anisotropic film of claim 1 to 7, wherein. 9. The liquid crystal display device according to claim 8 , wherein the liquid crystal display device is a twisted nematic type. 9. The liquid crystal display device according to claim 8 , wherein the liquid crystal display device has a polymer-dispersed light control layer.

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