JP4509856B2 - Liquid crystal display element and method for manufacturing liquid crystal display element - Google Patents

Description

  The present invention relates to a liquid crystal display element in which the orientation of ferroelectric liquid crystal is controlled, and more particularly to a liquid crystal display element with little cell gap fluctuation and excellent display quality.

  The liquid crystal display device has features such as power saving, light weight, thinness, and the like, and has rapidly spread in recent years in place of the conventional CRT display. A liquid crystal display element constituting a general liquid crystal display device has a configuration in which a liquid crystal layer composed of a regularly arranged liquid crystal material is sandwiched between two substrates having an alignment film, and a voltage is applied between the substrates. Thus, it has a function of displaying an image by changing the alignment state of the liquid crystal substance.

  The display quality of an image by the liquid crystal display element depends on the alignment state of the liquid crystal substance, and good display quality can be obtained by making the alignment state of the liquid crystal molecules uniform. Many factors that affect the alignment state of the liquid crystal substance are known, and one of them is a distance (cell gap) between two substrates sandwiching a liquid crystal layer. The cell gap corresponds to the thickness of the liquid crystal layer, and fixing the substrate so that the cell gap is uniform with high accuracy is indispensable for obtaining excellent display quality. In particular, liquid crystal display devices have recently become larger in screen size. For example, display quality is deteriorated due to a change in cell gap between the upper and lower portions of the screen due to the influence of gravity or the like. Such a problem is particularly problematic in a liquid crystal display element using a ferroelectric liquid crystal.

On the other hand, the ferroelectric liquid crystal (FLC) is a liquid crystal suitable for a high-speed device because the response speed is as short as μs order. In recent years, the state of a liquid crystal layer when a voltage is not applied has been stabilized in one state (hereinafter referred to as “monostable”). ) Is continuously changed and analog transmission of the transmitted light intensity is taken into account, so that gradation display is possible (Non-Patent Document 1, FIG. 7). As the ferroelectric liquid crystal capable of monostabilization in the liquid crystal layer, a material that changes phase with the cholesteric phase (Ch) -chiral smectic C (SmC ^* ) phase in the temperature lowering process and does not pass through the smectic A (SmA) phase is used. A material that changes phase with Ch-SmA-SmC ^* in the temperature lowering process and exhibits the SmC ^* phase via the SmA phase is known (FIG. 8).

  Ferroelectric liquid crystals are more difficult to align due to their higher molecular ordering than other liquid crystals typified by nematic liquid crystals, and defects such as zigzag defects and hairpin defects are likely to occur. It causes a decrease in contrast due to leakage. Further, the ferroelectric liquid crystal having no SmA phase in the phase series generates two regions having different layer normal directions (hereinafter referred to as “double domain”) (FIG. 8). Such a double domain causes a black / white reversal display during driving, which is a serious problem (FIG. 9). On the other hand, a ferroelectric liquid crystal having an SmA phase in a phase series usually has two stable states with respect to a single-layer normal, and is known to exhibit bistability. It is difficult to obtain. For this reason, in a liquid crystal display element using ferroelectric liquid crystals, the ferroelectric liquid crystal, which is inherently difficult to control the alignment, is stabilized in a monostable state. It is necessary not to occur.

  The cell gap of the liquid crystal display element is kept constant by a method in which a member usually called a spacer is arranged between the substrates. The method using such a spacer is roughly divided into a method using a bead-shaped spacer and a method using a pillar or wall spacer.

  The method using a bead-shaped spacer is a method of controlling the cell gap by making a bead-shaped spacer having a uniform particle size present in the liquid crystal layer, and has an advantage in that the cell gap can be easily made uniform. ing. However, in the method using bead-shaped spacers, the placement location of the bead-shaped spacers in the liquid crystal layer cannot be controlled, and as a result, the bead-shaped spacers are also disposed in the pixel portion essential for image display. There is a problem that causes deterioration in display quality of the element. In addition, since the method using bead-shaped spacers is not a method of positively fixing two substrates, it has a good effect on external force in the direction of narrowing the cell gap, but external force in the direction of widening of the cell gap. There is also a problem that it is not effective for.

  On the other hand, in the method using a columnar or wall-shaped spacer, the spacer can be arranged in a portion other than the pixel portion indispensable for image display by a photolithography method or the like, so that it is possible to prevent deterioration in display quality. Have. However, this method is also not a method of positively fixing two substrates, and thus has no effect on an external force in the direction in which the cell gap widens.

  Under such circumstances, Patent Document 1 uses a spacer having a photothermal conversion function, and after arranging the spacer between two substrates having a thermoplastic alignment film, by performing light irradiation, the spacer is removed. A method is disclosed in which both substrates are fixed at a constant cell gap by generating heat and fusing the alignment films and spacers of both substrates. Such a method is useful in that the substrate can be firmly fixed with a certain cell gap, but the constituent material of the alignment film is limited to a thermoplastic material, and there is a problem that the applicable range is narrow.

NONAKA, T., LI, J., OGAWA, A., HORNUNG, B., SCHMIDT, W., WINGEN, R., and DUBAL, H., 1999, Liq. Cryst., 26, 1599. JP 2004-13098 A

  The present invention has been made in view of the above problems, and in a liquid crystal display element using a ferroelectric liquid crystal, the ferroelectric liquid crystal is mono-stabilized and the substrate is firmly formed with a uniform cell gap. The main object is to provide a fixed liquid crystal display element.

To achieve the above object, the present invention provides a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, the first electrode, and the spacer. A spacer side substrate having a first alignment film formed thereon, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode Is arranged so that the first alignment film and the second alignment film face each other, and a liquid crystal layer made of a ferroelectric liquid crystal is sandwiched between the spacer side substrate and the counter substrate. A liquid crystal display element,
A reactive liquid crystal layer formed by immobilizing reactive liquid crystal is formed on either the first alignment film or the second alignment film, and the spacer-side substrate and the counter substrate are Provided is a liquid crystal display element which is bonded through the reactive liquid crystal layer.

  The liquid crystal display element of the present invention has a reactive liquid crystal layer in which either one of the spacer side substrate or the counter substrate fixes a reactive liquid crystal, and the spacer side substrate and the above-described liquid crystal layer are interposed through the reactive liquid crystal layer. By bonding the counter substrate, the spacer side substrate and the counter substrate can be firmly fixed with a uniform cell gap. Therefore, according to the present invention, it is possible to obtain a liquid crystal display element excellent in display quality in which the cell gap does not vary due to an external force.

  In addition, since the reactive liquid crystal layer in the present invention is formed by fixing the reactive liquid crystal, it can function as an alignment film for aligning the ferroelectric liquid crystal constituting the liquid crystal layer. It is possible to control the orientation of the ferroelectric liquid crystal more effectively than when only the above is used. Furthermore, according to the present invention, any one of the spacer side substrate and the counter substrate has a reactive liquid crystal layer on which reactive liquid crystal is immobilized, thereby generating alignment defects such as zigzag defects, hairpin defects, and double domains. And a monostable operation mode can be realized using a ferroelectric liquid crystal.

The present invention also provides a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and a first electrode formed on the first electrode and the spacer. A spacer-side substrate having an alignment film and a first reactive liquid crystal layer formed on the first alignment film and having a reactive liquid crystal fixed thereon, a second substrate, and the second substrate. The counter substrate having a second electrode, a second alignment film formed on the second electrode, and a second reactive liquid crystal layer formed on the second alignment film and immobilizing reactive liquid crystals. However, the first reactive liquid crystal layer and the second reactive liquid crystal layer are bonded so as to face each other, and a liquid crystal layer made of ferroelectric liquid crystal is sandwiched between the spacer side substrate and the counter substrate. A liquid crystal display element comprising:
There is provided a liquid crystal display element characterized in that the reactive liquid crystal constituting the first reactive liquid crystal layer and the reactive liquid crystal constituting the second reactive liquid crystal layer have different compositions.

The liquid crystal display element of the present invention is configured such that the spacer side substrate and the counter substrate are bonded to each other through the first reactive liquid crystal layer and the second reactive liquid crystal layer, so that the spacer side substrate and the counter substrate are opposed to each other. The substrate can be firmly fixed with a uniform cell gap. Therefore, according to the present invention, it is possible to obtain a liquid crystal display element excellent in display quality in which the cell gap does not vary due to an external force.

Further, the liquid crystal display element of the present invention is more effective in ferroelectricity than the case where the spacer side substrate and the counter substrate have only an alignment film because the spacer side substrate and the counter substrate have a reactive liquid crystal layer. The orientation of the crystalline liquid crystal can be controlled. Moreover, the reactive liquid crystal which comprises the 1st reactive liquid crystal layer formed on the said 1st alignment film, and the reactive liquid crystal which comprises the 2nd reactive liquid crystal layer formed on the said 2nd alignment film By using different compositions, the occurrence of alignment defects such as zigzag defects, hairpin defects, and double domains can be suppressed, and a monostable operation mode can be realized using a ferroelectric liquid crystal.

  In the said invention, it is preferable that the said reactive liquid crystal expresses a nematic phase. This is because the nematic phase is relatively easy to control the alignment among the liquid crystal phases.

  Also. In the said invention, it is preferable that the said reactive liquid crystal has a polymerizable liquid crystal monomer. The polymerizable liquid crystal monomer can be aligned at a lower temperature than other polymerizable liquid crystal materials, that is, a polymerizable liquid crystal oligomer and a polymerizable liquid crystal polymer, and has high sensitivity in alignment, and can be easily aligned. Because you can.

  Furthermore, in the said invention, it is preferable that the said polymeric liquid crystal monomer is a monoacrylate monomer or a diacrylate monomer. This is because the monoacrylate monomer or diacrylate monomer can be easily polymerized while maintaining the orientation state in a good state.

  Furthermore, in the said invention, it is preferable that the said diacrylate monomer is a compound represented by following formula (1).

  Here, X in the formula is hydrogen, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, alkyloxy having 1 to 20 carbons, alkyloxycarbonyl having 1 to 20 carbons, formyl, carbon number 1-20 alkylcarbonyl, C1-C20 alkylcarbonyloxy, halogen, cyano or nitro is represented, m represents an integer within the range of 2-20.

  Moreover, in the said invention, it is preferable that the said diacrylate monomer is a compound represented by following formula (2).

Here, Z ²¹ and Z ²² in the formula are each independently directly bonded —COO—, —OCO—, —O—, —CH ₂ CH ₂ —, —CH═CH—, —C≡. C—, —OCH ₂ —, —CH ₂ O—, —CH ₂ CH ₂ COO—, —OCOCH ₂ CH ₂ —, wherein l and m represent 0 or 1, and n is within the range of 2-8. Represents an integer. In the formula, R represents hydrogen or alkyl having 1 to 5 carbon atoms.

  In the present invention, it is preferable that the first alignment film and the second alignment film are photo-alignment films. This is because the photo-alignment process at the time of forming the photo-alignment film is a non-contact alignment process, so that it is useful in that there is no generation of static electricity and dust and quantitative alignment control is possible.

  Further, in the above invention, the constituent material of the photo-alignment film is a photoreactive material that imparts anisotropy to the photo-alignment film by causing a photoreaction, or the photo-alignment by causing a photoisomerization reaction. A photoisomerization type material containing a photoisomerization reactive compound that imparts anisotropy to the film is preferable. It is because anisotropy can be easily imparted to the photo-alignment film by using such a material.

  In the above invention, the ferroelectric liquid crystal is preferably mono-stabilized. This is because gradation display is possible because the transmitted light intensity can be analog-modulated by continuously changing the director of the liquid crystal by changing the voltage.

  Moreover, in this invention, it is preferable to have the sealing agent which consists of ultraviolet curable resin between the said spacer side board | substrate and the said opposing board | substrate. This is because the liquid crystal substance can be prevented from leaking from the liquid crystal layer by having the sealing agent. Moreover, when the sealing agent is made of an ultraviolet curable resin, for example, when an ultraviolet curable resin is used as the curable resin constituting the reactive alignment layer, the sealing agent and the reactive alignment layer are simultaneously cured. This is because the liquid crystal display element manufacturing method of the present invention can be simplified because it can be processed.

  In addition, the liquid crystal display element of the present invention is preferably driven by an active matrix method using a thin film transistor (TFT). This is because by adopting an active matrix system using a TFT element, a target pixel can be reliably turned on and off, so that a high-quality display is possible. Furthermore, a TFT substrate in which TFT elements are arranged in a matrix on one substrate and a common electrode substrate in which a common electrode is formed over the entire display portion on the other substrate are combined, and the common electrode substrate is shared. A micro color filter in which a matrix of TFT elements is arranged between an electrode and a substrate can be formed and used as a color liquid crystal display element.

  Furthermore, the liquid crystal display element according to the above invention is preferably driven by a field sequential color system. Since the liquid crystal display device according to the invention has a high response speed and can align the ferroelectric liquid crystal without causing alignment defects, it can be driven by a field sequential color system, thereby reducing power consumption and cost. This is because it is possible to realize a bright and high-definition color moving image display with a wide viewing angle.

The present invention also provides a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and a first electrode formed on the first electrode and the spacer. A spacer side substrate having an alignment film, a second substrate, a second electrode formed on the second substrate, and a counter substrate having a second alignment film formed on the second electrode are used. A method of manufacturing a liquid crystal display element,
An uncured reactive liquid crystal layer forming step of forming an uncured reactive liquid crystal layer containing a reactive liquid crystal on either the first alignment film or the second alignment film;
The spacer side substrate and the counter substrate are brought into contact so that the first alignment film and the second alignment film face each other through the uncured reactive liquid crystal layer formed in the uncured reactive liquid crystal layer forming step. Then, by fixing the reactive liquid crystal, the upper spacer side substrate and the counter substrate are bonded to form a liquid crystal display element substrate pair,
A liquid crystal layer forming step of forming a liquid crystal layer made of a ferroelectric liquid crystal between the spacer side substrate and the counter substrate of the liquid crystal display element substrate pair formed by the liquid crystal display element substrate pair forming step. A method for manufacturing a liquid crystal display element is provided.

  According to the present invention, since the spacer side substrate and the counter substrate can be firmly fixed via the reactive liquid crystal layer, a liquid crystal display element excellent in display quality without cell gap variation is manufactured. Can do.

  In addition, the liquid crystal display device manufactured according to the present invention has a reactive liquid crystal layer on either the first alignment film or the second alignment film, so that zigzag defects, hairpin defects, It is possible to obtain a liquid crystal display element that can suppress the occurrence of alignment defects such as double domains and can realize a monostable operation mode using a ferroelectric liquid crystal.

The present invention also provides a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and a first electrode formed on the first electrode and the spacer. A spacer side substrate having an alignment film, a second substrate, a second electrode formed on the second substrate, and a counter substrate having a second alignment film formed on the second electrode are used. A method of manufacturing a liquid crystal display element,
An uncured reactive liquid crystal layer forming step of forming an uncured reactive liquid crystal layer containing reactive liquid crystals having different compositions on the first alignment film and the second alignment film;
The uncured reactive liquid crystal layer formed on the first alignment film by the uncured reactive liquid crystal layer forming step and the uncured reactive liquid crystal layer formed on the second alignment film are brought into contact with each other. Then, by fixing the reactive liquid crystal, the upper spacer side substrate and the counter substrate are bonded to form a liquid crystal display element substrate pair forming step,
A liquid crystal layer forming step of forming a liquid crystal layer made of a ferroelectric liquid crystal between the spacer side substrate and the counter substrate of the liquid crystal display element substrate pair formed by the liquid crystal display element substrate pair forming step. A method for manufacturing a liquid crystal display element is provided.

According to the method for manufacturing a liquid crystal display element of the present invention, the uncured reactive liquid crystal layer is formed on the first alignment film and the second alignment film, so that the alignment film alone is used. A liquid crystal display element in which the orientation of the ferroelectric liquid crystal is controlled can be obtained. Moreover, the reactive liquid crystal contained in the uncured reactive liquid crystal layer formed on the first alignment film, and the reactive liquid crystal contained in the uncured reactive liquid crystal layer formed on the second alignment film. In order to obtain a liquid crystal display that can suppress the occurrence of alignment defects such as zigzag defects, hairpin defects, and double domains, and can realize a monostable operation mode using a ferroelectric liquid crystal. Can do.

  According to the present invention, in a liquid crystal display element using a ferroelectric liquid crystal, it is possible to obtain a liquid crystal display element in which the ferroelectric liquid crystal is mono-stabilized and the substrate is firmly fixed with a uniform cell gap. There is an effect.

  Hereinafter, the liquid crystal display element of the present invention and the method for manufacturing the liquid crystal display element will be described in detail.

A. Liquid Crystal Display Element First, the liquid crystal display element of the present invention will be described. The liquid crystal display element of the present invention is roughly classified into two modes depending on the structure of the reactive liquid crystal layer formed by fixing the reactive liquid crystal. Hereinafter, the liquid crystal display element of the present invention will be described in detail for each embodiment.

A-1. First Embodiment Liquid Crystal Display Element First, the liquid crystal display element of the first embodiment of the present invention will be described. The liquid crystal display element according to the first aspect of the present invention includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, the first electrode, and the spacer. A spacer side substrate having a first alignment film formed thereon, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode Is arranged so that the first alignment film and the second alignment film face each other, and a liquid crystal layer made of a ferroelectric liquid crystal is sandwiched between the spacer side substrate and the counter substrate. A liquid crystal display element,
A reactive liquid crystal layer formed by immobilizing reactive liquid crystal is formed on either the first alignment film or the second alignment film, and the spacer-side substrate and the counter substrate are It is characterized by being bonded via the reactive liquid crystal layer.

  Next, the liquid crystal display element of this embodiment will be described with reference to the drawings. FIG. 1A is a schematic cross-sectional view showing an example of the liquid crystal display element of this embodiment. As shown in FIG. 1A, the liquid crystal display element 10a of this embodiment is formed on the first substrate 1a, the first electrode 2a formed on the first substrate 1a, and the first electrode 2a. A spacer 4, a first alignment film 3a formed on the first electrode 2a and the spacer 4, a reactive liquid crystal layer 5 formed on the first alignment film 3a and having a reactive liquid crystal fixed thereon; A spacer-side substrate 11 having a second substrate 1b, a second electrode 2b formed on the second substrate 1b, and a second alignment film 3b formed on the second electrode 2b. A substrate 12 is disposed so that the reactive liquid crystal layer 5 and the second alignment film 3b are bonded, and a liquid crystal layer 6 made of a ferroelectric liquid crystal is interposed between the spacer side substrate 11 and the counter substrate 12. Is sandwiched between. As illustrated in FIG. 1A, the liquid crystal display element of this embodiment may include a sealant 7 and polarizing plates 8a and 8b that prevent leakage of the ferroelectric liquid crystal.

  The liquid crystal display element of this embodiment has a reactive liquid crystal layer in which either one of the spacer side substrate or the counter substrate fixes a reactive liquid crystal, and the spacer side substrate and the above-described liquid crystal layer are interposed through the reactive liquid crystal layer. By bonding the counter substrate, the spacer-side substrate and the counter substrate can be firmly fixed with a uniform cell gap. Therefore, according to this aspect, it is possible to obtain a liquid crystal display element excellent in display quality in which the cell gap does not vary due to external force.

  In addition, since the reactive liquid crystal layer in this embodiment is formed on the first alignment of the spacer-side substrate or the second alignment film of the counter substrate, the reactive liquid crystal constituting the reactive liquid crystal layer is It becomes possible to arrange regularly by the action of the first alignment film or the second alignment film. Thus, by fixing the reactive liquid crystal in a state where the reactive liquid crystal is regularly arranged, the reactive liquid crystal layer can function as an alignment film for aligning the ferroelectric liquid crystal. Further, the reactive liquid crystal has a relatively similar structure to the ferroelectric liquid crystal, so that the interaction with the ferroelectric liquid crystal becomes strong. Therefore, the liquid crystal display element of this embodiment can control the alignment of the ferroelectric liquid crystal more effectively than the case where only the alignment film is used by having the reactive liquid crystal layer.

  Furthermore, the liquid crystal display element of this embodiment has the above-mentioned reactive liquid crystal layer on either the first alignment film or the second alignment film, thereby making the ferroelectric liquid crystal constituting the liquid crystal layer monostable. Therefore, the occurrence of alignment defects such as zigzag defects, hairpin defects, and double domains can be suppressed, and a monostable operation mode can be realized using ferroelectric liquid crystal. The mechanism by which the ferroelectric liquid crystal can be mono-stabilized by having the reactive liquid crystal layer is not clear, but is thought to be due to the following mechanism. That is, by forming a reactive liquid crystal layer on either the first alignment film or the second alignment film, the alignment liquid crystal has an alignment ability with respect to the ferroelectric liquid crystal and has a different composition from each other. The liquid crystal layer is sandwiched. For this reason, there is a difference in the interaction between the ferroelectric liquid crystal and the alignment film above and below the liquid crystal layer. Therefore, it is considered that the polarization direction of the ferroelectric liquid crystal is aligned in one direction and monostable.

  Hereafter, each structure of the liquid crystal display element of this aspect is demonstrated in detail.

1. Reactive liquid crystal layer First, the reactive liquid crystal layer which the liquid crystal display element of this aspect has is demonstrated. The reactive liquid crystal layer included in the liquid crystal display element of this embodiment is formed on one of the first alignment film of the spacer side substrate and the second alignment film of the counter substrate, and the spacer side substrate, the counter substrate, It has the function to adhere | attach. In addition, since the reactive liquid crystal can be aligned by the action of the first alignment film or the second alignment film, for example, the reactive liquid crystal is polymerized by irradiating ultraviolet rays, and the alignment state is fixed. It can function as an alignment film for aligning the dielectric liquid crystal. Further, since the reactive liquid crystal is fixed, it has an advantage that it is not affected by temperature or the like. Furthermore, reactive liquid crystals are relatively similar in structure to ferroelectric liquid crystals, and the interaction with the ferroelectric liquid crystals is stronger, so the ferroelectric liquid crystals are more effective than using only an alignment film. Can be controlled. Hereinafter, the reactive liquid crystal layer used in this embodiment will be described.

(1) Reactive liquid crystal The reactive liquid crystal used in the reactive liquid crystal layer exhibits adhesion to the spacer-side substrate and the counter substrate, and constitutes the liquid crystal layer by regularly arranging them. The ferroelectric liquid crystal is not particularly limited as long as it exhibits alignment ability. In this embodiment, such a reactive liquid crystal preferably exhibits a nematic phase. This is because the nematic phase is relatively easy to control the alignment among the liquid crystal phases.

  The reactive liquid crystal preferably has a polymerizable liquid crystal material. This is because the alignment state of the reactive liquid crystal can be fixed. As such a polymerizable liquid crystal material, any of a polymerizable liquid crystal monomer, a polymerizable liquid crystal oligomer, and a polymerizable liquid crystal polymer can be used. In this embodiment, a polymerizable liquid crystal monomer is preferably used. The polymerizable liquid crystal monomer can be aligned at a lower temperature than other polymerizable liquid crystal materials, that is, a polymerizable liquid crystal oligomer and a polymerizable liquid crystal polymer, and has high sensitivity in alignment, and can be easily aligned. Because you can.

  The polymerizable liquid crystal monomer is not particularly limited as long as it is a liquid crystal monomer having a polymerizable functional group, and examples thereof include a monoacrylate monomer and a diacrylate monomer. These polymerizable liquid crystal monomers may be used alone or in combination of two or more.

  As a monoacrylate monomer, the compound represented, for example by a following formula can be illustrated.

In the above formula, A, B, D, E and F represent benzene, cyclohexane or pyrimidine, and these may have a substituent such as halogen. A and B, or D and E may be bonded via a bonding group such as an acetylene group, a methylene group, or an ester group. M ¹ and M ² may be any of a hydrogen atom, an alkyl group having 3 to 9 carbon atoms, an alkoxycarbonyl group having 3 to 9 carbon atoms, or a cyano group. Furthermore, the acryloyloxy group at the end of the molecular chain and A or D may be bonded via a spacer such as an alkylene group having 3 to 6 carbon atoms.

  Moreover, as a diacrylate monomer, the compound as shown to a following formula can be mentioned, for example.

  In the above formula, X and Y are hydrogen, alkyl having 1 to 20 carbons, alkenyl having 1 to 20 carbons, alkyloxy having 1 to 20 carbons, alkyloxycarbonyl having 1 to 20 carbons, formyl, carbon number 1-20 alkylcarbonyl, C1-C20 alkylcarbonyloxy, halogen, cyano or nitro is represented. M represents an integer in the range of 2-20.

  Furthermore, examples of the diacrylate monomer include compounds represented by the following formula.

In the above formula, Z ²¹ and Z ²² are each independently directly bonded —COO—, —OCO—, —O—, —CH ₂ CH ₂ —, —CH═CH—, —C≡C—. _{, -OCH 2 -, - CH 2} O -, - CH 2 CH 2 COO -, - OCOCH 2 CH 2 - represents a. L and m represent 0 or 1, and n represents an integer in the range of 2-8. In the formula, R represents hydrogen or alkyl having 1 to 5 carbon atoms.

  Specific examples of the formula (2) include a compound represented by the following formula (3).

In the formula (3), Z ²¹ and Z ²² are each independently directly bonded —COO—, —OCO—, —O—, —CH ₂ CH ₂ —, —CH═CH—, —C. ≡C—, —OCH ₂ —, —CH ₂ O—, —CH ₂ CH ₂ COO—, —OCOCH ₂ CH ₂ —, m represents 0 or 1, and n represents an integer in the range of 2-8. Represents.

In this embodiment, among them, compounds represented by the above formula (1) and the above formula (2) are preferably used. In the case of the compound represented by the above formula (1), X is preferably an alkyloxycarbonyl having 1 to 20 carbon atoms, methyl or chlorine, and particularly an alkyloxycarbonyl having 1 to 20 carbon atoms, particularly CH _3. Preferably it is (CH ₂ ) ₄ OCO. Specific examples of the compound represented by the formula (2) include Adeka Kiracol PLC-7209 (Asahi Denka Kogyo Co., Ltd.), Adeka Kiracol PCL-7183 (Asahi Denka Kogyo Co., Ltd.), and the like. it can.

  Among the above, the polymerizable liquid crystal monomer used in this embodiment is preferably a diacrylate monomer. This is because the diacrylate monomer can maintain the orientation state well by being polymerized.

  The polymerizable liquid crystal monomer described above does not have to exhibit a nematic phase. In this embodiment, these polymerizable liquid crystal monomers may be used as a mixture of two or more kinds as described above, and the composition in which these are mixed, that is, the reactive liquid crystal exhibits a nematic phase. It is because it is good.

  Furthermore, in this aspect, you may add a photoinitiator and a polymerization inhibitor to the said reactive liquid crystal as needed. For example, when polymerizing a polymerizable liquid crystal material by electron beam irradiation, a photopolymerization initiator may not be necessary, but in the case of polymerization by, for example, ultraviolet irradiation, usually photopolymerization is started. This is because the agent is used for promoting the polymerization.

  Examples of the photopolymerization initiator that can be used in this embodiment include benzyl (also referred to as bibenzoyl), benzoin isobutyl ether, benzoin isopropyl ether, benzophenone, benzoylbenzoic acid, benzoylmethyl benzoate, and 4-benzoyl-4′-methyldiphenyl sulfide. Benzylmethyl ketal, dimethylaminomethyl benzoate, 2-n-butoxyethyl-4-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, 3,3′-dimethyl-4-methoxybenzophenone, methylobenzoyl formate, 2 -Methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, -(4 Dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl)- 2-hydroxy-2-methylpropan-1-one, 2-chlorothioxanthone, 2,4-diethylthioxanthone 2,4-diisopropylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 1-chloro-4-propoxythioxanthone, etc. Can be mentioned. In addition to the photopolymerization initiator, it is also possible to add a sensitizer as long as the object of the present invention is not impaired.

  The amount of the photopolymerization initiator added is generally 0.01 to 20% by mass, preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass. It can be added to the liquid crystal.

  Furthermore, when using the said photoinitiator, a photoinitiator adjuvant can be used together. Examples of such photopolymerization initiation assistants include tertiary amines such as triethanolamine and methyldiethanolamine, and benzoic acid derivatives such as ethyl 2-dimethylaminoethylbenzoate and ethyl 4-dimethylamidebenzoate. Yes, but not limited to these.

(2) Reactive liquid crystal layer The reactive liquid crystal layer which the liquid crystal display element of this aspect has is formed on either the first alignment film of the spacer side substrate or the second alignment film of the counter substrate. It ’s fine. Specifically, referring to the drawings, each aspect in the case where the reactive liquid crystal layer is formed on at least one of the first alignment film of the spacer side substrate or the second alignment film of the counter substrate is specifically described. explain. FIG. 1A shows an embodiment in which the reactive liquid crystal layer 5 is formed on the first alignment film 3a of the spacer-side substrate 11 as described above. As an aspect of the reactive liquid crystal layer in the present invention, in addition to the above aspect, an aspect in which the reactive liquid crystal layer 5 is formed on the second alignment film 3b of the counter substrate 12 as shown in FIG. Can be mentioned.
The reactive liquid crystal layer in the present invention may be in any form of an aspect formed on the first alignment film of the spacer side substrate or an aspect formed on the second alignment film of the counter substrate. Especially, the aspect in which the reactive liquid crystal layer in this invention was formed on the 2nd alignment film of a counter substrate is preferable. When the reactive liquid crystal layer is formed on the spacer side substrate, the presence of the spacer may cause the thickness of the reactive liquid crystal layer to be non-uniform, or the effect of the curable resin may be uneven. This is because there are no such problems.

  The reactive liquid crystal layer preferably has a thickness in the range of 1 nm to 1000 nm, more preferably in the range of 3 nm to 100 nm. This is because if the reactive liquid crystal layer is thicker than the above range, anisotropy more than necessary may occur. Further, if it is thinner than the above range, the adhesive force between the spacer side substrate and the counter substrate may be insufficient.

  In this embodiment, the thickness of the reactive liquid crystal layer may or may not be uniform. For example, as shown in FIG. 2, when the reactive liquid crystal layer is formed on the first alignment film of the spacer side substrate, it is formed between the portion A formed on the spacer 4 and the two spacers 4. The thickness of the reactive liquid crystal layer in the portion B and the portion C formed on the wall portion of the spacer 4 may be the same or different as long as they are within the above range.

(3) Others The reactive liquid crystal layer in this embodiment has a function of adhering the spacer side substrate and the counter substrate, but the term “adhesion” as used herein means that the spacer side substrate and the counter substrate do not come into contact with each other. More specifically, it means that they are in contact with each other with an adhesive force that does not separate from each other under their own weight.

2. Next, the spacer side substrate used in this embodiment will be described. The spacer-side substrate used in this aspect includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and the first electrode and the spacer. A first alignment film formed. In addition, the spacer-side substrate of this embodiment may have the above-described reactive liquid crystal layer on the first alignment film. Hereinafter, each structure of such a spacer side board | substrate is demonstrated.

(1) Spacer First, the spacer used for the spacer side substrate will be described. The spacer used for the spacer side substrate is formed on the first substrate, and has a function of maintaining a uniform cell gap between the spacer side substrate and the counter substrate. Moreover, in the liquid crystal display element of this aspect, the said spacer side board | substrate and the said opposing board | substrate adhere | attach at the site | part in which the spacer is formed.

  The shape of the spacer used for the spacer side substrate is not particularly limited as long as the spacer side substrate and the counter substrate can be bonded to each other at the spacer portion, and is necessary depending on the number of spacers formed on the first substrate. It is possible to arbitrarily determine a shape that can exhibit a good adhesive force. As the shape of the spacer used in this embodiment, for example, the cross-sectional shape of the surface perpendicular to the first substrate is square, rectangular, or trapezoidal, and the cross-sectional shape of the surface parallel to the first substrate is circular or multi-directional. Mention may be made of squares, squares, rectangles or trapezoids. Specific examples of the shape include a wall shape shown in FIG. 3A and a columnar shape shown in FIG. Note that the description of the first alignment film and the reactive liquid crystal layer is omitted in FIGS.

  The spacers are usually formed at a plurality of locations on the first substrate, but the plurality of spacers are preferably formed regularly at predetermined positions. This is because if the positions at which the plurality of spacers are formed are disordered, the holding power of the cell gap with respect to the external force becomes non-uniform, and depending on the position, the display quality may be deteriorated due to fluctuations in the cell gap.

In the case where the spacers are regularly formed, the pitch between the spacers may be appropriately determined according to the driving method of the liquid crystal display element of the present invention. For example, when the liquid crystal display element of the present invention is driven by an active matrix method using a thin film transistor (TFT), the pitch between the spacers is preferably an integer multiple of the pitch of the pixel electrodes. It is preferable that the pitch is 2 to 50 times, more preferably 5 to 20 times, and within a range of 50 μm to 3 mm.
Note that the spacer pitch refers to the distance from the center to the center of adjacent spacers. For example, when the spacer has a wall shape as shown in FIG. 3A, the distance between the centers of adjacent spacers (the distance indicated by D in FIG. 3A) may be within the above range. On the other hand, when the spacer is columnar, the center-to-center distance with at least one of the plurality of adjacent spacers may be within the above range. For example, as shown in FIG. In the case of arranging regularly, either one of the distances indicated by E or F in FIG.

  The width of the spacer is not particularly limited as long as the spacer side substrate and the counter substrate can be bonded to each other and display quality is not deteriorated. Especially in this invention, it is preferable that the width | variety of a spacer exists in the range of 1 micrometer-20 micrometers, and it is especially preferable that it exists in the range of 2 micrometers-10 micrometers. This is because if the width of the spacer is narrower than the above range, it may be difficult to form the spacer with high accuracy. In addition, when the width of the spacer is wider than the above range, for example, when the liquid crystal display element of the present invention is driven by an active matrix method using a thin film transistor (TFT), the effective pixel area becomes small, and the entire liquid crystal display element This is because the display quality may be deteriorated as a result of the decrease in the aperture ratio.

  Further, the height of the spacer is not particularly limited as long as it is not more than the thickness of the liquid crystal layer described later and does not impair the orientation of the ferroelectric liquid crystal constituting the liquid crystal layer. Is preferably substantially the same as the thickness of the liquid crystal layer. This is because the impact resistance can be effectively improved. Specifically, it is preferably in the range of 1 μm to 5 μm, particularly preferably in the range of 1.2 μm to 2 μm, and particularly preferably in the range of 1.2 μm to 1.5 μm.

  Note that the pitch, width, and height of the spacer are values measured by observation using a scanning electron microscope (SEM).

  The spacer is preferably formed so as to avoid the pixel region. This is because the alignment failure of the ferroelectric liquid crystal tends to occur in the vicinity of the spacer, and it is preferable that the spacer is formed in a region that does not affect image display.

  Also, the surface on which the spacer is formed on the first substrate is not particularly limited as long as it is a surface capable of fixing the spacer. Therefore, it may be formed on the surface of the first substrate or may be formed on the surface of the first electrode, but in this embodiment, it is preferably formed on the surface of the first electrode. This is because by forming the spacer on the surface of the first electrode, there is no possibility of short-circuiting with the second electrode, and the manufacturing process can be simplified.

  Further, the number of spacers formed on the first substrate is not particularly limited as long as it is plural, and the size of the liquid crystal display element, the shape of the spacer, and the space between the spacer side substrate and the counter substrate are obtained. What is necessary is just to determine arbitrarily according to adhesive force etc.

  The material for forming the spacer is not particularly limited as long as it is a material generally used as a spacer of a liquid crystal display element. Specific examples include resins, and among these, photosensitive resins are preferably used. This is because the photosensitive resin is easy to pattern. The photosensitive resin used in this embodiment is not particularly limited as long as it is generally used for a spacer of a liquid crystal display element. For example, it is described in the section of “B. Manufacturing method of liquid crystal display element” described later. Materials can be used.

(2) 1st board | substrate Next, the 1st board | substrate used for this aspect is demonstrated. The 1st board | substrate used for this aspect will not be specifically limited if generally used as a board | substrate of a liquid crystal display element, For example, a glass plate, a plastic plate, etc. are mentioned preferably. The surface roughness (RSM value) of the first substrate is preferably 10 nm or less, more preferably 3 nm or less, and still more preferably 1 nm or less. In the present embodiment, the surface roughness can be measured with an atomic force microscope (AFM: ATOMIC FORCE MICROSCOPE).

(3) 1st electrode Next, the 1st electrode used for a spacer side board | substrate is demonstrated. The first electrode used for the spacer side substrate is not particularly limited as long as it is generally used as an electrode of a liquid crystal display element, but at least one of the first electrode and the second electrode described later is a transparent conductive material. It is preferably formed of a body. Preferred examples of the material for the transparent conductor include indium oxide, tin oxide, indium tin oxide (ITO), and the like. When the liquid crystal display element of this embodiment is an active matrix liquid crystal display element using TFT, one of the first electrode of the spacer side substrate and the second electrode layer of the counter substrate is made of the transparent conductor. This is because the entire surface common electrode is formed, and on the other side, the x electrode and the y electrode are arranged in a matrix, and the TFT element and the pixel electrode are arranged in a portion surrounded by the x electrode and the y electrode. In this case, it is preferable that the difference between the uneven portions of the electrode layer formed by the pixel electrode, the TFT element, the x electrode, and the y electrode is 0.2 μm or less. This is because if the difference between the concave and convex portions of the electrode layer exceeds 0.2 μm, alignment disorder is likely to occur.

(4) First Alignment Film Next, the first alignment film used for the spacer side substrate will be described. Although it does not specifically limit as a 1st alignment film used for a spacer side board | substrate, What has the alignment ability with respect to the said reactive liquid crystal is preferable. By using the one having the alignment ability for the reactive liquid crystal, the alignment ability of the liquid crystal molecules of the reactive liquid crystal layer can be improved, so that the alignment stability of the ferroelectric liquid crystal constituting the liquid crystal layer can be improved. is there. As such a first alignment film, for example, a film subjected to a rubbing process, a photo-alignment process or the like can be used, but in this embodiment, a photo-alignment film subjected to a photo-alignment process is preferably used. This is because the photo-alignment process is a non-contact alignment process, which is useful in that it does not generate static electricity or dust and can quantitatively control the alignment process. Hereinafter, such a photo-alignment film will be described.

  The photo-alignment film irradiates the first substrate coated with the constituent material of the photo-alignment film, which will be described later, with light having a controlled polarization, thereby causing a photoexcitation reaction (decomposition, isomerization, dimerization), thereby causing anisotropy. It is given.

  The constituent material of the photo-alignment film used for the first alignment film is not particularly limited as long as it exhibits anisotropy in the first alignment film by irradiating light to cause a photoexcitation reaction. As such materials, there are large photoreactive materials that impart anisotropy to the photoalignment film by causing a photoreaction, and anisotropy is imparted to the photoalignment film by causing a photoisomerization reaction. It can be divided into photoisomerization reaction type materials. In addition, the wavelength region of light in which the constituent material of the photo-alignment film causes a photoexcitation reaction is preferably in the ultraviolet region, that is, in the range of 10 nm to 400 nm, and preferably in the range of 250 nm to 380 nm. More preferred. Each will be described below.

(Photoreactive type)
First, a photoreactive component material will be described. As described above, the photoreactive component material is a material that imparts anisotropy to the photoalignment film by causing a photoreaction. The photoreactive constituent material used in this embodiment is not particularly limited as long as it has such characteristics, but among these, the above-mentioned light can be produced by causing a photodimerization reaction or a photolysis reaction. A material that imparts anisotropy to the alignment film is preferred.

  Here, the photodimerization reaction refers to a reaction in which a reaction site oriented in the polarization direction by light irradiation undergoes radical polymerization and two molecules are polymerized. This reaction stabilizes the orientation in the polarization direction and makes the photo-alignment film different. It is possible to impart directionality. On the other hand, the photodecomposition reaction is a reaction that decomposes molecular chains such as polyimide oriented in the polarization direction by light irradiation. This reaction leaves a molecular chain oriented in the direction perpendicular to the polarization direction, and is different from the photo-alignment film. It is possible to impart directionality. In this embodiment, among these photoreactive materials, it is more preferable to use a material that imparts anisotropy to the first alignment film by a photodimerization reaction because of high exposure sensitivity and wide range of material selection. preferable.

  The photoreactive material utilizing such photodimerization reaction is not particularly limited as long as it is a material that can impart anisotropy to the first alignment film by the photodimerization reaction. It is preferable to include a photodimerization reactive compound having a dichroic property having a functional group and having different absorption depending on the polarization direction. This is because radical polymerization of the reaction sites oriented in the polarization direction stabilizes the orientation of the photodimerization reactive compound and can easily impart anisotropy to the first alignment film.

  Examples of the photodimerization reactive compound having such characteristics include a dimerization reactive polymer having at least one reactive site selected from cinnamate ester, coumarin, quinoline, chalcone group and cinnamoyl group as a side chain. Can do.

  Among these, the photodimerization reactive compound is preferably a dimerization reactive polymer containing cinnamate, coumarin or quinoline as a side chain. This is because anisotropy can be easily imparted to the first alignment film by radical polymerization of α and β unsaturated ketone double bonds aligned in the polarization direction as reaction sites.

  The main chain of the dimerization reactive polymer is not particularly limited as long as it is generally known as a polymer main chain, but the reaction sites of the side chains such as aromatic hydrocarbon groups are not limited. It is preferable that it does not have a substituent containing a lot of π electrons that hinders the interaction.

  The weight average molecular weight of the dimerization reactive polymer is not particularly limited, but is preferably in the range of 5,000 to 40,000, and is preferably in the range of 10,000 to 20,000. Is more preferable. The weight average molecular weight can be measured by a gel permeation chromatography (GPC) method. If the weight-average molecular weight of the dimerization reactive polymer is too small, it may not be possible to impart appropriate anisotropy to the first alignment film. On the other hand, if it is too large, the viscosity of the coating liquid at the time of forming the first alignment film increases, and it may be difficult to form a uniform coating film.

  As a dimerization reactive polymer, the compound represented by a following formula can be illustrated.

In the above formula, M ¹¹ and M ¹² each independently represent a monomer unit of a monopolymer or a copolymer. Examples thereof include ethylene, acrylate, methacrylate, 2-chloroacrylate, acrylamide, methacrylamide, 2-chloroacrylamide, styrene derivatives, maleic acid derivatives, and siloxane. M ¹² may be acrylonitrile, methacrylonitrile, methacrylate, methyl methacrylate, hydroxyalkyl acrylate or hydroxyalkyl methacrylate. x and y represent the molar ratio of each monomer unit in the case of a copolymer, and are numbers satisfying 0 <x ≦ 1, 0 ≦ y <1 and satisfying x + y = 1, respectively. It is. n represents an integer of 4 to 30,000. D ¹ and D ² represent spacer units.

R ¹ is a group represented by -A ^1- (Z ¹ -B ¹ ) _z -Z ^2- , and R ² is represented by -A ^1- (Z ¹ -B ¹ ) _z -Z ^3-. It is a group. Here, A ¹ and B ¹ are each independently a covalent single bond, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4-cyclohexylene, 1,3-dioxane-2, It represents 5-diyl or 1,4-phenylene which may have a substituent. Z ¹ and Z ² are each independently a covalent single bond, —CH ₂ —CH ₂ —, —CH ₂ O—, —OCH ₂ —, —CONR—, —RNCO—, —COO— or — Represents OOC-. R is a hydrogen atom or a lower alkyl group, and Z ³ is a hydrogen atom or an alkyl or alkoxy having 1 to 12 carbon atoms, which may have a substituent, cyano, nitro, or halogen. z is an integer of 0-4. E ¹ represents a photodimerization reaction site, and examples thereof include cinnamic acid ester, coumarin, quinoline, chalcone group, cinnamoyl group and the like. j and k are each independently 0 or 1.

  As such a dimerization reactive polymer, More preferably, the compound represented by a following formula can be mentioned.

  Among the dimerization reactive polymers, at least one of compounds 1 to 4 represented by the following formula is particularly preferable.

  In this embodiment, as the photodimerization reactive compound, various photodimerization reaction sites and substituents can be selected from the above-described compounds according to the required characteristics for the first alignment film. Moreover, the photodimerization reactive compound can also be used individually by 1 type or in combination of 2 or more types.

  In addition to the photodimerization reactive compound, the photoreaction type material utilizing the photodimerization reaction may contain an additive within a range that does not interfere with the photoalignment of the first alignment film. Examples of the additive include a polymerization initiator and a polymerization inhibitor.

  The polymerization initiator or polymerization inhibitor may be appropriately selected from generally known compounds according to the type of the photodimerization reactive compound. The addition amount of the polymerization initiator or the polymerization inhibitor is preferably in the range of 0.001% by mass to 20% by mass, and in the range of 0.1% by mass to 5% by mass with respect to the photodimerization reactive compound. It is more preferable that This is because if the addition amount of the polymerization initiator or polymerization inhibitor is too small, the polymerization may not be started (prohibited), whereas if too large, the reaction may be inhibited.

  Note that the photoreactive material using the photodecomposition reaction is not particularly limited as long as it is a material that causes a reaction of decomposing molecular chains such as polyimide oriented in the polarization direction by light irradiation. Examples of such a photoreactive material include polyimide “RN1199” manufactured by Nissan Chemical Industries, Ltd.

(Photoisomerization type)
Next, the photoisomerization type material will be described. As used herein, the photoisomerization type material is a material that imparts anisotropy to the first alignment film by causing a photoisomerization reaction as described above. It is not limited. In particular, in this embodiment, it is preferable to include a photoisomerization reactive compound that imparts anisotropy to the first alignment film by causing a photoisomerization reaction. By including such a photoisomerization reactive compound, a stable isomer among a plurality of isomers is increased by light irradiation, whereby anisotropy can be easily imparted to the first alignment film. Because.

  Such a photoisomerization-reactive compound is not particularly limited as long as it is a material having the above-mentioned characteristics, but has a dichroism that makes absorption different depending on the polarization direction, and light It is preferable that a photoisomerization reaction is caused by irradiation. This is because anisotropy can be easily imparted to the first alignment film by causing isomerization of the reaction site oriented in the polarization direction of the photoisomerization reactive compound having such characteristics.

  The photoisomerization reaction that produces such a photoisomerization-reactive compound is preferably a cis-trans isomerization reaction. This is because either the cis isomer or the trans isomer is increased by light irradiation, whereby anisotropy can be imparted to the first alignment film.

  Examples of such photoisomerization-reactive compounds include monomolecular compounds and polymerizable monomers that are polymerized by light or heat. These may be appropriately selected according to the type of the ferroelectric liquid crystal to be used. However, the anisotropy is imparted to the first alignment film by light irradiation, and then polymerized to stabilize the anisotropy. Therefore, it is preferable to use a polymerizable monomer. Among such polymerizable monomers, after anisotropy is imparted to the first alignment film, it can be easily polymerized while maintaining the anisotropy in a good state, so that it may be an acrylate monomer or a methacrylate monomer. preferable.

  The polymerizable monomer may be a monofunctional monomer or a polyfunctional monomer. However, since the anisotropy of the first alignment film due to polymerization becomes more stable, it is a bifunctional monomer. A monomer is preferred.

  Specific examples of such a photoisomerization-reactive compound include compounds having a cis-trans isomerization-reactive skeleton such as an azobenzene skeleton or a stilbene skeleton.

  In this case, the number of cis-trans isomerization reactive skeletons contained in the molecule may be one or two or more, but the alignment control of the ferroelectric liquid crystal becomes easy. Two are preferable.

  The cis-trans isomerization reactive skeleton may have a substituent in order to further enhance the interaction with the liquid crystal molecules. The substituent is not particularly limited as long as it can enhance the interaction with the liquid crystal molecules and does not interfere with the orientation of the cis-trans isomerization reactive skeleton, and examples thereof include a carboxyl group and a sulfonic acid. A sodium group, a hydroxyl group, etc. are mentioned. These structures can be appropriately selected depending on the type of ferroelectric liquid crystal used.

In addition to the cis-trans isomerization reactive skeleton, the photoisomerization reactive compound contains many π electrons such as aromatic hydrocarbon groups so that the interaction with the liquid crystal molecules can be further enhanced. It may have an included group, and the cis-trans isomerization reactive skeleton and the aromatic hydrocarbon group may be bonded via a bonding group. The bonding group is not particularly limited as long as it can enhance the interaction with the liquid crystal molecule. For example, —COO—, —OCO—, —O—, —C≡C—, —CH ₂ —CH _2- , —CH ₂ O—, —OCH ₂ — and the like can be mentioned.

  In addition, when using a polymerizable monomer as a photoisomerization reactive compound, it is preferable to have the said cis-trans isomerization reactive skeleton as a side chain. By having the cis-trans isomerization reactive skeleton as a side chain, the effect of anisotropy imparted to the first alignment film becomes larger, and the ferroelectric liquid crystal constituting the liquid crystal layer has This is because it is particularly suitable for array control. In this case, the aromatic hydrocarbon group or bonding group contained in the molecule is contained in the side chain together with the cis-trans isomerization reactive skeleton so that the interaction with the liquid crystal molecule is enhanced. It is preferable.

  Further, the side chain of the polymerizable monomer may have an aliphatic hydrocarbon group such as an alkylene group as a spacer so that the cis-trans isomerization reactive skeleton can be easily oriented.

  Among the photoisomerization reactive compounds of the monomolecular compound or polymerizable monomer as described above, the photoisomerization reactive compound used in this embodiment is preferably a compound having an azobenzene skeleton in the molecule. This is because the azobenzene skeleton contains a lot of π electrons, and thus has high interaction with liquid crystal molecules, and is particularly suitable for stabilizing the alignment of the ferroelectric liquid crystal constituting the liquid crystal layer.

  Hereinafter, the reason why an azobenzene skeleton can impart anisotropy to the first alignment film by causing a photoisomerization reaction will be described. First, when the azobenzene skeleton is irradiated with linearly polarized ultraviolet light, the trans azobenzene skeleton having the molecular long axis oriented in the polarization direction is changed to a cis isomer as shown in the following formula.

  Since the cis isomer of the azobenzene skeleton is chemically unstable compared to the trans isomer, it thermally or absorbs visible light and returns to the trans isomer. Whether to become the right transformer body occurs with the same probability. Therefore, if the ultraviolet light is continuously absorbed, the ratio of the right-side trans isomer increases, and the average orientation direction of the azobenzene skeleton becomes perpendicular to the polarization direction of the ultraviolet light. In this embodiment, by utilizing this phenomenon, the orientation direction of the azobenzene skeleton is aligned, anisotropy is imparted to the first alignment film, and the alignment of the liquid crystal molecules on the film can be controlled.

  Among such compounds having an azobenzene skeleton in the molecule, examples of the monomolecular compound include compounds represented by the following formula.

  Moreover, as a polymerizable monomer which has the said azobenzene skeleton as a side chain, the compound represented by a following formula can be mentioned, for example.

  In this embodiment, various cis-trans isomerization reactive skeletons and substituents can be selected from such photoisomerization reactive compounds according to required characteristics. In addition, these photoisomerization reactive compounds can also be used individually by 1 type or in combination of 2 or more types.

  In addition to the photoisomerization reactive compound, the photoisomerization type material used in this embodiment may contain an additive within a range that does not interfere with the photoalignment property of the photoalignment film. When a polymerizable monomer is used as the photoisomerization reactive compound, examples of the additive include a polymerization initiator and a polymerization inhibitor.

  The polymerization initiator or polymerization inhibitor may be appropriately selected from generally known compounds according to the type of photoisomerization reactive compound. The addition amount of the polymerization initiator or polymerization inhibitor is preferably in the range of 0.001% by mass to 20% by mass, and in the range of 0.1% by mass to 5% by mass with respect to the photoisomerization reactive compound. More preferably, it is within. This is because if the addition amount of the polymerization initiator or polymerization inhibitor is too small, the polymerization may not be started (prohibited), whereas if too large, the reaction may be inhibited.

(5) Reactive liquid crystal layer A reactive liquid crystal layer may be formed on the first alignment film of the spacer side substrate. The reactive liquid crystal layer used for the spacer-side substrate is the same as that described in the above section “1. Reactive liquid crystal layer”, and thus the description thereof is omitted here.

3. Next, the counter substrate used in this embodiment will be described. The counter substrate in this aspect includes a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode. The counter substrate of this aspect may have the above-described reactive liquid crystal layer on the first alignment film.
Here, the second substrate, the second electrode, and the second alignment film used for the counter substrate are the first substrate, the first electrode, and the first alignment film described in the section “2. Spacer side substrate”. The description is omitted here. Further, the reactive liquid crystal layer used for the counter substrate is the same as that described in the section “1. Reactive liquid crystal layer”, and the description thereof is omitted here.

4. Liquid Crystal Layer The liquid crystal layer used in this embodiment is configured by sandwiching a ferroelectric liquid crystal between the spacer side substrate and the counter substrate. The ferroelectric liquid crystal used in this embodiment is not particularly limited as long as it exhibits a chiral smectic C phase (SmC ^* ). As the phase series of the ferroelectric liquid crystal, for example, a phase change of nematic phase (N) -cholesteric phase (Ch) -chiral smectic C phase (SmC ^* ), nematic phase (N) -chiral smectic C phase (SmC ^*) ), Nematic phase (N) -smectic A phase (SmA) -chiral smectic C phase (SmC ^* ), phase change, nematic phase (N) -cholesteric phase (Ch) -smectic A phase ( SmA) -chiral smectic C phase (SmC ^* ) phase change and the like.

  In general, a ferroelectric liquid crystal having a phase sequence passing through an SmA phase as illustrated in the lower part of FIG. 8 has a smectic layer in order to compensate for the volume change because the layer spacing of the smectic layer is reduced during the phase change process. A domain having a bent chevron structure and different major axis directions of the liquid crystal molecules is formed depending on the bending direction, and alignment defects called zigzag defects and hairpin defects are likely to occur at the interface. In general, a ferroelectric liquid crystal having a phase sequence that does not pass through the SmA phase illustrated in the upper part of FIG. 8 is likely to generate two regions (double domains) having different layer normal directions. In this embodiment, the monodomain alignment of the ferroelectric liquid crystal can be obtained without causing such alignment defects.

  When the liquid crystal display element of this embodiment is driven by a field sequential color system, it is preferable to use a liquid crystal material exhibiting monostability. By using a liquid crystal material exhibiting monostability, it becomes possible to drive by an active matrix method using thin film transistors (TFTs), and to control gradation by voltage modulation, so that high-definition and high-quality display can be achieved. This is because it can be realized.

  Here, “showing monostability” means a state in which the state of the ferroelectric liquid crystal when no voltage is applied is stabilized in one state. More specifically, as shown in FIG. 10, the liquid crystal molecule 37 has two stable states inclined by a tilt angle ± θ with respect to the layer normal z, and operates between the two stable states on a cone. The liquid crystal molecules 37 are stabilized in any one state on the cone when no voltage is applied.

Among liquid crystal materials exhibiting monostability, for example, as shown in the lower left of FIG. 7, liquid crystal molecules operate only when a positive or negative voltage is applied, which is hereinafter referred to as HV-shaped switching. .) Those exhibiting properties are particularly preferred. When the ferroelectric liquid crystal exhibiting such HV-shaped switching characteristics is used, the opening time as a black and white shutter can be made sufficiently long, whereby each color that can be temporally switched can be displayed brighter. This is because a bright color display liquid crystal display element can be realized.
Here, the “HV-shaped switching characteristic” refers to an electro-optical characteristic in which the light transmittance with respect to the applied voltage is asymmetric.

  Such a ferroelectric liquid crystal can be variously selected from generally known liquid crystal materials according to required characteristics.

As the liquid crystal material that does not pass through the SmA phase, a material that expresses the SmC ^* phase from the Ch phase without passing through the SmA phase is preferable. Such a liquid crystal material is suitable for exhibiting HV-shaped switching characteristics. Specifically, “R2301” manufactured by AZ Electronic Materials may be mentioned.

In addition, as the liquid crystal material that passes through the SmA phase, a material that expresses the SmC ^* phase from the Ch phase through the SmA phase is preferable because of a wide range of material selection. In this case, a single liquid crystal material exhibiting an SmC ^* phase can be used, but a non-chiral liquid crystal (hereinafter sometimes referred to as a host liquid crystal) having a low viscosity and easily exhibiting an SmC phase is used. By adding a small amount of an optically active substance that does not show large spontaneous polarization and an appropriate helical pitch, the liquid crystal material showing the phase sequence as described above has low viscosity and can realize faster response. preferable.

The host liquid crystal is preferably a material exhibiting an SmC phase in a wide temperature range, and can be used without particular limitation as long as it is generally known as a host liquid crystal of a ferroelectric liquid crystal. For example, the general formula:
^{Ra-Q 1 -X 1 - (} Q 2 -Y 1) m -Q 3 -Rb
(In the formula, Ra and Rb are each a linear or branched alkyl group, alkoxy group, alkoxycarbonyl group, alkanoyloxy group or alkoxycarbonyloxy group, and Q ¹ , Q ² and Q ³ are each 1 , 4-phenylene group, 1,4-cyclohexylene group, pyridine-2,5-diyl group, pyrazine-2,5-diyl group, pyridazine-3,6-diyl group, 1,3-dioxane-2,5 -Diyl group, and these groups may have a substituent such as a halogen atom, a hydroxyl group, and a cyano group, and X ¹ and Y ¹ are each —COO—, —OCO—, —CH ₂ O— , —OCH ₂ —, —CH ₂ CH ₂ —, —C≡C—, or a single bond, and m is 0 or 1.). As the host liquid crystal, the above compounds can be used alone or in combination of two or more.

The optically active substance added to the host liquid crystal is not particularly limited as long as it is a material having a large spontaneous polarization and the ability to induce an appropriate helical pitch, and is generally added to a liquid crystal composition exhibiting an SmC phase. Any known material can be used. In particular, a material that can induce large spontaneous polarization with a small addition amount is preferable. Examples of such an optically active substance include the following general formula:
^{Rc-Q 1 -Za-Q 2} -Zb-Q 3 -Zc-Rd
(In the formula, Rd, Q ¹ , Q ² and Q ³ represent the same meaning as in the above general formula, and Za and Zb are —COO—, —OCO—, —CH ₂ O—, —OCH ₂ —, —CH _{2, respectively.} CH ₂ —, —C≡C—, —CH═N—, —N═N—, —N (→ O) ═N—, —C (═O) S— or a single bond, and Rc is asymmetric. A linear or branched alkyl group which may have a carbon atom, an alkoxy group, an alkoxycarbonyl group, an alkanoyloxy group or an alkoxycarbonyloxy group, wherein Rd is a linear or branched group having an asymmetric carbon atom; And an alkyl group, an alkoxy group, an alkoxycarbonyl group, an alkanoyloxy group or an alkoxycarbonyloxy group, and Rc and Rd may be substituted with a halogen atom, a cyano group or a hydroxyl group. Can be used. As the optically active substance, the above compounds may be used alone or in combination of two or more.

  Specific examples of the ferroelectric liquid crystal passing through the SmA phase include “FELIXM4851-100” manufactured by AZ Electronic Materials.

  The ferroelectric liquid crystal is preferably mono-stabilized in the liquid crystal layer. Because the above-mentioned ferroelectric liquid crystal is mono-stabilized in the liquid crystal layer, the liquid crystal director can be continuously changed by voltage change, and the transmitted light intensity can be analog-modulated, so that gradation display is possible. is there.

  The thickness of the liquid crystal layer is preferably in the range of 1 μm to 5 μm, more preferably in the range of 1.2 μm to 2 μm, and still more preferably in the range of 1.2 μm to 1.5 μm. This is because if the thickness of the liquid crystal layer is too thin, the contrast may be lowered. Conversely, if the thickness of the liquid crystal layer is too thick, the ferroelectric liquid crystal may be difficult to align.

5). Others The liquid crystal display element in the present invention may have other configurations in addition to the spacer side substrate, the counter substrate, and the liquid crystal layer. Examples of such other configurations include a polarizing plate and a sealing agent.

  The polarizing plate used in the present invention is not particularly limited as long as it transmits only a specific direction in the wave of light, and a polarizing plate generally used as a polarizing plate of a liquid crystal display element may be used. it can.

  In this aspect, it is preferable to have a sealing agent between the spacer side substrate and the counter substrate. This is because the liquid crystal substance can be prevented from leaking from the liquid crystal layer by having the sealing agent. As a constituent material of the sealant used in the present invention, those generally used for a sealant of a liquid crystal display element can be used. Examples of such a material include a resin, and any of a thermosetting resin and an ultraviolet curable resin can be used. Especially in this invention, it is preferable that the said sealing agent consists of ultraviolet curable resin. When the sealing agent is made of an ultraviolet curable resin, for example, when an ultraviolet curable resin is used as the curable resin constituting the reactive alignment layer, the sealing agent and the reactive alignment layer are simultaneously cured. This is because the manufacturing method of the liquid crystal display element of the present invention can be simplified. As a sealing agent used for this invention, UV hardening sealing agent (Brand name LCB610: EHC company make) can be mentioned, for example.

  The driving method of the liquid crystal display device of this embodiment is preferably an active matrix method using a thin film transistor (TFT). This is because by adopting an active matrix system using a TFT element, a target pixel can be reliably turned on and off, so that a high-quality display is possible.

FIG. 4 is a schematic perspective view showing an example of an active matrix liquid crystal display element using the TFT of this embodiment. The liquid crystal display element 20 illustrated in FIG. 4 includes a TFT substrate 21a in which TFTs 25 are arranged in a matrix on one substrate 22a, and a common electrode substrate 21b in which a common electrode 23 is formed on the other substrate 22b. Is. An x electrode 24x, a y electrode 24y, and a pixel electrode 24t are formed on the TFT substrate 21a. In such a liquid crystal display element 20, the x electrode 24x and the y electrode 24y are arranged vertically and horizontally, respectively, and the TFT element 25 is operated by applying a signal to these electrodes 24x and 24y to drive the ferroelectric liquid crystal. Can be made. A portion where the x electrode 24x and the y electrode 24y intersect with each other is insulated by an insulating layer (not shown), and the signal of the x electrode 24x and the signal of the y electrode 24y can operate independently. A portion surrounded by the x electrode 24x and the y electrode 24y is a pixel which is a minimum unit for driving the liquid crystal display element of this embodiment, and at least one TFT element 25 and a pixel electrode 24t are formed in each pixel. ing. In the liquid crystal display element 20, the TFT element 25 of each pixel can be operated by sequentially applying a signal voltage to the x electrode 24x and the y electrode 24y.
In FIG. 4, the liquid crystal layer and the alignment film are omitted.

  When the liquid crystal display element of this embodiment is driven by an active matrix method using the TFT element, the spacer side substrate may be the TFT substrate, the counter substrate may be the common electrode substrate, and the counter substrate may be The TFT substrate may be used, and the spacer side substrate may be the common electrode substrate.

  The liquid crystal display element of this embodiment can be a liquid crystal display element capable of color display by adopting a color filter method or a field sequential color method. For example, in the liquid crystal display element shown in FIG. 4, color display is possible by arranging a micro color filter on the TFT substrate side or the common electrode substrate side.

  The liquid crystal display element of this embodiment is particularly preferably driven by a field sequential color system. In the field sequential color system, one pixel is time-divided, and high-speed response is required to obtain good moving image display characteristics. In this embodiment, by utilizing the high-speed response of the ferroelectric liquid crystal, color display is possible by combining with an LED light source without using a micro color filter. In addition, since the ferroelectric liquid crystal can be aligned without causing alignment defects, a wide viewing angle, high-speed response, and high-definition color display can be realized. Further, according to the field sequential color method, it is not necessary to form a black matrix on the common electrode substrate side, so that it becomes easy to form a reactive liquid crystal layer in the method of manufacturing a liquid crystal display element according to this embodiment described later. Therefore, there is an advantage in terms of productivity.

  When the liquid crystal display element of this embodiment is driven by the field sequential color system, a liquid crystal material that exhibits a chiral smectic C phase from the cholesteric phase without passing through the smectic A phase and exhibits monostability is used as the ferroelectric liquid crystal. It is preferable. Such a liquid crystal material exhibits HV-shaped switching characteristics as described above, and the opening time as a black and white shutter can be sufficiently long. Accordingly, each color that can be switched over time can be displayed brighter, and a bright full-color liquid crystal display element can be realized.

  When the ferroelectric liquid crystal exhibits monostability, the liquid crystal display element of this embodiment is basically driven by an active matrix system using TFTs, but can also be driven by a segment system.

  The manufacturing method of the liquid crystal display element of this aspect is not particularly limited as long as it can manufacture each of the components described above. For example, the manufacturing method described in the section “B. Manufacturing method of liquid crystal display element” is used. Can be manufactured.

A-2. Next, the liquid crystal display element of the second aspect of the present invention will be described. A liquid crystal display element according to a second aspect of the present invention includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, the first electrode, and the spacer. A spacer-side substrate having a first alignment film formed thereon, a first reactive liquid crystal layer formed on the first alignment film and having a reactive liquid crystal fixed thereon; a second substrate; and A second electrode formed on the second substrate; a second alignment film formed on the second electrode; and a second reactivity formed on the second alignment film by immobilizing a reactive liquid crystal. A counter substrate having a liquid crystal layer is bonded so that the first reactive liquid crystal layer and the second reactive liquid crystal layer face each other, and ferroelectricity is provided between the spacer side substrate and the counter substrate. A liquid crystal display element having a liquid crystal layer sandwiched between liquid crystals,
The reactive liquid crystal constituting the first reactive liquid crystal layer and the reactive liquid crystal constituting the second reactive liquid crystal layer have different compositions.

Next, the liquid crystal display element of this embodiment will be described with reference to the drawings. FIG.1 (c) is a schematic sectional drawing which shows an example of the liquid crystal display element of this aspect. As shown in FIG. 1C, the liquid crystal display element 10b of this embodiment is formed on the first substrate 1a, the first electrode 2a formed on the first substrate 1a, and the first electrode 2a. A spacer 4, a first alignment film 3a formed on the first electrode 2a and the spacer 4, and a first reactive liquid crystal layer formed on the first alignment film 3a and fixing a reactive liquid crystal. A spacer-side substrate 11 ′ having 5a, a second substrate 1b, a second electrode 2b formed on the second substrate 1b, and a second alignment film 3b formed on the second electrode 2b. The counter substrate 12 ′ having the second reactive liquid crystal layer 5 b formed on the second alignment film 3 b and having the reactive liquid crystal fixed thereon is composed of the first reactive liquid crystal layer 5 a and the second reaction liquid crystal layer 5 b. The liquid crystal layer 5b is bonded so as to face each other, and A liquid crystal display device formed by sandwiching a liquid crystal layer 6 of ferroelectric liquid crystal server side substrate 11 '12 and between the counter substrate',
The reactive liquid crystal constituting the first reactive liquid crystal layer 5a and the reactive liquid crystal constituting the second reactive liquid crystal layer 5b have different compositions. In addition, as illustrated in FIG. 1C, the liquid crystal display element of this embodiment may include a sealant 7 and polarizing plates 8a and 8b that prevent leakage of ferroelectric liquid crystal.

  The liquid crystal display element according to this aspect is configured so that the spacer side substrate and the counter substrate are bonded to each other by bonding the spacer side substrate and the counter substrate through the first reactive liquid crystal layer and the second reactive liquid crystal layer. The substrate can be firmly fixed with a uniform cell gap. Therefore, according to this aspect, it is possible to obtain a liquid crystal display element excellent in display quality in which the cell gap does not vary due to external force.

  Further, the liquid crystal display element of this embodiment is more effective in ferroelectricity than the case where the spacer side substrate and the counter substrate have only an alignment film because the spacer side substrate and the counter substrate have a reactive liquid crystal layer. The orientation of the crystalline liquid crystal can be controlled. Moreover, the reactive liquid crystal which comprises the 1st reactive liquid crystal layer formed on the said 1st alignment film, and the reactive liquid crystal which comprises the 2nd reactive liquid crystal layer formed on the said 2nd alignment film By using different compositions, the occurrence of alignment defects such as zigzag defects, hairpin defects, and double domains can be suppressed, and a monostable operation mode can be realized using a ferroelectric liquid crystal.

  Hereinafter, each structure of the liquid crystal display element of this aspect is demonstrated.

1. Spacer side substrate The spacer side substrate used in the liquid crystal display element of this aspect includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and the first electrode. A first alignment film formed on one electrode and the spacer, and a first reactive liquid crystal layer formed on the first alignment film and having a reactive liquid crystal fixed thereon. The first substrate, the first electrode, the spacer, and the first alignment film are the same as those described in the section “A-1. Liquid crystal display element of the first aspect 2. Spacer side substrate”. Since it is the same, description here is abbreviate | omitted.

  The reactive liquid crystal constituting the first reactive liquid crystal layer is not particularly limited as long as it has a composition different from that of the reactive liquid crystal constituting the second reactive liquid crystal described later. About the reactive liquid crystal which comprises a 1st reactive liquid crystal layer, and the matter regarding the other 1st reactive liquid crystal layer, it describes in the said "A-1. Liquid crystal display element of a 1st aspect 1. Reactive liquid crystal layer". Since it is the same as what was done, description here is abbreviate | omitted.

2. The counter substrate used in the liquid crystal display element of this aspect includes a second substrate, a second electrode formed on the second substrate, a second alignment film formed on the second electrode, and the above A second reactive liquid crystal layer formed on the second alignment film and having a reactive liquid crystal immobilized thereon. The second substrate, the second electrode, and the second alignment film are the same as those described in the above section “A-1. Liquid crystal display element of the first aspect 3. Counter substrate”. Explanation here is omitted.

  The reactive liquid crystal constituting the second reactive liquid crystal layer is not particularly limited as long as it has a composition different from that of the reactive liquid crystal constituting the first reactive liquid crystal described above. About the reactive liquid crystal which comprises a 2nd reactive liquid crystal layer, and the matter regarding the other 2nd reactive liquid crystal layer, it describes in the above-mentioned "A-1. Liquid crystal display element of 1st aspect 1. Reactive liquid crystal layer". Since it is the same as what was done, description here is abbreviate | omitted.

3. Liquid Crystal Layer The liquid crystal layer used in the liquid crystal display element of this embodiment is the same as that described in the above section “A-1. Liquid Crystal Display Element of First Embodiment 4. Liquid Crystal Layer”. Is omitted.

4). Others Other matters relating to the liquid crystal display element of the present embodiment are the same as those described in the above section “A-1. Liquid crystal display element of the first embodiment 5. Others”, and thus the description thereof is omitted here. .

B. Next, a method for manufacturing the liquid crystal display device of the present invention will be described. The method of manufacturing a liquid crystal display device according to the present invention includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, the first electrode, and the spacer. A spacer-side substrate having a first alignment film formed on the second substrate, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode; The manufacturing method of the liquid crystal display element using the counter substrate which has this.

  The manufacturing method of the liquid crystal display element of this invention can be divided roughly into two aspects by the aspect of an uncured reactive liquid crystal layer formation process. Hereafter, the manufacturing method of the liquid crystal display element of this invention is demonstrated for every aspect.

B-1. First, a method for manufacturing a liquid crystal display element according to the first aspect will be described. The method of manufacturing a liquid crystal display element according to the first aspect of the present invention includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, and the first electrode. And a spacer side substrate having a first alignment film formed on the spacer, a second substrate, a second electrode formed on the second substrate, and a second electrode formed on the second electrode. A method of manufacturing a liquid crystal display element using a counter substrate having a two-alignment film, wherein an uncured reactive liquid crystal layer containing a reactive liquid crystal is formed on either the first alignment film or the second alignment film An uncured reactive liquid crystal layer forming step;
The spacer side substrate and the counter substrate are brought into contact so that the first alignment film and the second alignment film face each other through the uncured reactive liquid crystal layer formed in the uncured reactive liquid crystal layer forming step. Then, by fixing the reactive liquid crystal, the spacer-side substrate and the counter substrate are bonded to form a liquid crystal display element substrate pair,
A liquid crystal layer forming step of forming a liquid crystal layer made of a ferroelectric liquid crystal between the spacer side substrate and the counter substrate of the liquid crystal display element substrate pair formed by the liquid crystal display element substrate pair forming step. It is characterized by this.

Next, the manufacturing method of the liquid crystal display element of this aspect is demonstrated, referring a figure. FIG. 5 is a process diagram showing an example of the manufacturing method of this embodiment. As shown in FIG. 5, in the manufacturing method of this aspect, first, a first substrate 1a, a first electrode 2a formed on the first substrate 1a, a spacer 4 formed on the first electrode 2a, The spacer-side substrate 11 having the first electrode 2a and the first alignment film 3a formed on the spacer 4, the second substrate 1b, and the second electrode 2b formed on the second substrate 1b And a counter substrate 12 having the second alignment film 3b formed on the second electrode 2b is prepared (FIG. 5A).
Next, an uncured reactive liquid crystal layer 5 ′ containing a reactive liquid crystal is formed on the first alignment film 3a of the spacer side substrate 11 (uncured reactive liquid crystal layer forming step: FIG. 5B).
Next, after the spacer-side substrate 11 ′ and the counter substrate 12 are brought into contact with each other so that the first alignment film 3a and the second alignment film 3b face each other through the uncured reactive liquid crystal layer 5 ′. By fixing the reactive liquid crystal by ultraviolet irradiation or the like, the spacer side substrate and the counter substrate are bonded to form the liquid crystal display element substrate pair 30 (liquid crystal display element substrate pair forming step: FIG. 5 (c)).
Next, after injecting a liquid crystal layer made of ferroelectric liquid crystal between the spacer side substrate 11 and the counter substrate 12 of the liquid crystal display element substrate pair 30, the liquid crystal layer 6 is sealed with a sealant 7. (Liquid crystal layer forming step: FIG. 5D). In this embodiment, a liquid crystal display element is manufactured by the above process.

  According to this aspect, since the spacer side substrate and the counter substrate can be firmly fixed via the reactive liquid crystal layer, a liquid crystal display element excellent in display quality with no cell gap variation is manufactured. Can do.

  In addition, the liquid crystal display device manufactured according to the present aspect has a reactive liquid crystal layer on one of the first alignment film and the second alignment film, thereby allowing zigzag defects, hairpin defects and double domains of ferroelectric liquid crystals. It is possible to obtain a liquid crystal display element that can suppress the occurrence of alignment defects such as the above and can realize a monostable operation mode using a ferroelectric liquid crystal.

  Hereafter, the manufacturing method of the liquid crystal display element of this aspect is demonstrated in detail.

1. Uncured reactive liquid crystal layer forming step First, the uncured reactive liquid crystal layer forming step in this embodiment will be described. In the present embodiment, the uncured reactive liquid crystal layer forming step includes an uncured reactive liquid crystal containing a reactive liquid crystal on either the first alignment film of the spacer side substrate or the second alignment film of the counter substrate. It is a process of forming a layer.
The uncured reactive liquid crystal layer formed in this step becomes a reactive liquid crystal layer by fixing the reactive liquid crystal in the liquid crystal display element substrate pair forming step described later.

(1) Spacer-side substrate process A spacer-side substrate forming process for forming a spacer-side substrate used in the method for producing a liquid crystal display element of this embodiment will be described. The spacer side substrate forming step is formed on the first substrate, the first electrode formed on the first substrate, the spacer formed on the first electrode, and the first electrode and the spacer. It is a step of forming a spacer side substrate having a first alignment film. Usually, the spacer side substrate forming step includes a first electrode forming step of forming a first electrode on the first substrate, and a spacer forming of forming a spacer on the first electrode formed by the first electrode forming step. And a first alignment film forming step of forming a first alignment film on the first electrode and the spacer after the spacer forming step.

i) First Electrode Formation Step First, the first electrode formation step will be described. The first electrode forming step is a step of forming a first electrode layer on the first substrate.

a. The first substrate The first substrate used in the first substrate forming step is the same as that described in the above section “A-1. Liquid crystal display element of first embodiment 2. Spacer side substrate”. Description of is omitted.

b. Method for Forming First Electrode The method for forming the first electrode on the first substrate is not particularly limited as long as it can form the first electrode having a uniform thickness. Examples of the method for forming the first electrode include chemical vapor deposition (CVD), physical vapor deposition (PVD) such as sputtering, ion plating, and vacuum deposition. Further, as a method for patterning the electrode layer, a general electrode patterning method can be applied.

  Since the other points of the first electrode are the same as those described in the above section “A-1. Liquid crystal display element of the first embodiment 2. Spacer side substrate”, description thereof is omitted here. .

ii) Spacer forming step Next, the spacer forming step will be described. The spacer forming step is a step of forming a spacer on the first electrode formed by the first electrode forming step.

  The method for forming the spacer on the first electrode is not particularly limited as long as it can accurately form a spacer having a desired shape at a predetermined position, and a general patterning method is applied. can do. As such a patterning method, it can be formed by a known method such as a 2P (Photo Polymerization) method, a photolithography method, an ink jet method, a screen printing method or the like. In the 2P method, for example, ethylene glycol (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) ) Acrylate, hexane glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, glycerin tridi (meth) acrylate, trimethylolpropane di (meth) acrylate, 1,4-butanediol di Acrylate, pentaerythritol (meth) acrylate, dipentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate , UV curable monomers such as dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, urethane acrylate, epoxy acrylate, polyester acrylate, epoxy, vinyl ether, polyene / thiol based oligomers, photodimerization reaction A resin composition such as a photocrosslinkable polymer such as polyvinyl cinnamate-based resin is applied on a substrate, and cured by irradiating with ultraviolet rays in a state where the original plate for spacer formation is pressure-bonded to the coating film. A spacer is formed by peeling off the film. In the photolithography method, a material as exemplified in the above-mentioned 2P method is applied on a substrate, the coating film is exposed through a desired photomask for forming a spacer, and then developed to remove the spacer. Form. In addition, said (meth) acrylate means an acrylate or a methacrylate.

  Since the other points of the spacer are the same as those described in the above section “A-1. Liquid crystal display element of first embodiment 2. Spacer side substrate”, description thereof is omitted here.

iii) First alignment film forming step Next, the first alignment film forming step will be described. The first alignment film forming step is a step of forming the first alignment film on the first electrode and the spacer formed by the first electrode forming step and the spacer forming step. In the first alignment film forming step, a rubbing alignment film may be formed, or a photo-alignment film may be formed.

a. Forming method of photo-alignment film In order to form the photo-alignment film in the first alignment film forming step, first, a photo-alignment film-forming coating solution obtained by diluting the constituent material of the photo-alignment film with an organic solvent is applied on the electrode layer. ,dry. In this case, the content of the photodimerization reactive compound or photoisomerization reactive compound in the photoalignment film-forming coating solution is preferably in the range of 0.05% by mass to 10% by mass. More preferably, it is in the range of 2% by mass to 2% by mass. When the content is less than the above range, it becomes difficult to impart appropriate anisotropy to the first alignment film. Conversely, when the content is more than the above range, the viscosity of the photoalignment film forming coating solution is high. This is because it becomes difficult to form a uniform coating film.

  As a coating method of the photo-alignment film forming coating solution, for example, a spin coating method, a roll coating method, a rod bar coating method, a spray coating method, an air knife coating method, a slot die coating method, a wire bar coating method and the like can be used. .

  The thickness of the film obtained by applying the coating liquid for forming a photo-alignment film is preferably in the range of 1 nm to 2000 nm, more preferably in the range of 3 nm to 100 nm. This is because if the thickness of the film is thinner than the above range, sufficient optical alignment may not be obtained, and conversely, if the thickness is thicker than the above range, it may be disadvantageous in cost.

  Anisotropy is imparted to the obtained film by performing a photo-alignment treatment. Specifically, by irradiating the obtained film with light whose polarization is controlled, an anisotropy can be imparted by causing a photoexcitation reaction. The wavelength range of the light to be irradiated may be appropriately selected according to the constituent material of the first photo-alignment film, but is preferably in the ultraviolet light range, that is, in the range of 100 nm to 400 nm, more preferably 250 nm. Within the range of ˜380 nm.

  Furthermore, when a polymerizable monomer is used as a constituent material of the photo-alignment film, among the photoisomerization reactive compounds, after photo-alignment treatment, it is polymerized by heating and applied to the first alignment film. Anisotropy can be stabilized.

b. Method for forming rubbing film The method for forming the rubbing film in the first alignment film forming step is not particularly limited, and generally a method for forming a rubbing film for a liquid crystal display element can be applied.

c. Others The constituent material and other points of the first alignment film are the same as those described in the above section “A-1. Liquid crystal display element of first embodiment 2. Spacer side substrate”. Description of is omitted.

(2) Counter substrate forming step Next, a counter substrate forming step of forming a counter substrate used in the method for manufacturing a liquid crystal display element of this aspect will be described. The counter substrate forming step is a step of forming a counter substrate having a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode. Usually, in such a counter substrate forming process, a second electrode forming process for forming a second electrode on the second substrate, and a second alignment film is formed on the second electrode formed by the second electrode forming process. A second alignment film forming step.

i) Second electrode forming step The second electrode forming step is a step of forming the second electrode on the second substrate. The method of forming the second electrode in the second electrode forming step is the same as that described in the above section “1. Spacer side substrate forming step i) First electrode forming step”, and the description thereof is omitted here. To do.

  In addition, regarding the second substrate used in the second electrode formation step, the constituent material of the second electrode, and other points related to the second electrode, the above-mentioned “A-1. Liquid crystal display element of the first aspect 3. Counter substrate” Since it is the same as that described in the above, description thereof is omitted here.

ii) Second alignment film forming step The second alignment film forming step is a step of forming a second alignment film on the second electrode formed by the second electrode forming step. The method of forming the second alignment film in the second alignment film forming step is the same as that described in the section “1. Spacer side substrate forming step iii) First alignment film forming step”. Description is omitted.

  Further, the constituent material and other points of the second alignment film are the same as those described in the above-mentioned section “A-1. Liquid crystal display element of the first aspect 3. Counter substrate”. Is omitted.

(3) Method for forming uncured reactive liquid crystal layer Next, a method for forming an uncured reactive liquid crystal layer in this step will be described. In this step, as a method of forming an uncured reactive liquid crystal layer, a reactive liquid crystal layer-forming coating liquid containing reactive liquid crystals is applied, alignment treatment is performed, and the alignment state of the reactive liquid crystals is fixed. Examples thereof include a method and a method of previously forming a dry film or the like made of reactive liquid crystals and laminating them. In this embodiment, a reactive liquid crystal layer forming coating liquid containing reactive liquid crystals is applied. Then, an alignment treatment is preferably performed to fix the alignment state of the reactive liquid crystal. This is because such a method has an advantage that the uncured reactive liquid crystal layer forming step can be simplified.

  The solvent used in the reactive liquid crystal layer-forming coating solution is particularly limited as long as it can dissolve the reactive liquid crystal and the like and does not inhibit the alignment ability of the first alignment film or the second alignment film. It is not done. For example, hydrocarbons such as benzene, toluene, xylene, n-butylbenzene, diethylbenzene and tetralin; ethers such as methoxybenzene, 1,2-dimethoxybenzene and diethylene glycol dimethyl ether; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 2 Ketones such as 1,4-pentanedione; esters such as ethyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, γ-butyrolactone; 2-pyrrolidone, N-methyl-2-pyrrolidone, dimethylformamide, dimethyl Amide solvents such as acetamide; t-butyl alcohol, diacetone alcohol, glycerin, monoacetin, ethylene glycol, triethyleneglycol 1 or 2 types of alcohols such as phenol and hexylene glycol; phenols such as phenol and parachlorophenol; cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, and ethylene glycol monomethyl ether acetate; is there.

  Further, if only a single kind of solvent is used, the solubility of the reactive liquid crystal or the like may be insufficient, or the first alignment film may be eroded. In this case, this inconvenience can be avoided by using a mixture of two or more solvents. Among the above-mentioned solvents, hydrocarbons and glycol monoether acetate solvents are preferable as the sole solvent, and a mixed system of ethers or ketones and glycol solvent is preferable as the mixed solvent. It is.

  The concentration of the coating liquid for forming the reactive liquid crystal layer depends on the solubility of the reactive liquid crystal and the thickness of the reactive liquid crystal layer, but cannot be defined unconditionally, but is usually 0.1% by mass to 40% by mass, Preferably, it adjusts in the range of 1 mass%-20 mass%. When the concentration of the reactive liquid crystal layer forming coating liquid is lower than the above range, the reactive liquid crystal may be difficult to align, and conversely when the concentration of the reactive liquid crystal layer forming coating liquid is higher than the above range, This is because the viscosity of the coating liquid for forming a reactive liquid crystal layer is increased, so that it may be difficult to form a uniform coating film.

Furthermore, the following compounds can be added to the reactive liquid crystal layer-forming coating solution as long as the object of the present invention is not impaired. Examples of compounds that can be added include polyester (meth) acrylate obtained by reacting (meth) acrylic acid with a polyester prepolymer obtained by condensing polyhydric alcohol and monobasic acid or polybasic acid; A polyurethane (meth) acrylate obtained by reacting a compound having two isocyanate groups with each other and then reacting the reaction product with (meth) acrylic acid; bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolak Type epoxy resins, polycarboxylic acid polyglycidyl esters, polyol polyglycidyl ethers, aliphatic or cycloaliphatic epoxy resins, amine epoxy resins, triphenolmethane type epoxy resins, dihydroxybenzene type epoxy resins and the like (meth) Acry Photopolymerizable compound in epoxy (meth) acrylate obtained by reacting an acid; photopolymerizable liquid crystal compound having an acryl group and a methacryl group; and the like.
The amount of these compounds added to the reactive liquid crystal is selected within a range that does not impair the object of the present invention. Addition of these compounds improves the curability of the reactive liquid crystal, increases the mechanical strength of the resulting reactive liquid crystal layer, and improves its stability.

  Examples of the application method of the coating liquid for forming the reactive liquid crystal layer include spin coating, roll coating, printing, dip coating, die coating, casting, bar coating, blade coating, and spray coating. Method, gravure coating method, reverse coating method, extrusion coating method and the like.

  In addition, the solvent is removed after the reactive liquid crystal layer forming coating solution is applied, and the removal of the solvent is performed by, for example, removal under reduced pressure or removal by heating, or a combination thereof. .

  In this step, the reactive liquid crystal applied as described above is aligned by the first alignment film or the second alignment film to have liquid crystal regularity. That is, a nematic phase is developed in the reactive liquid crystal. This is usually performed by a method such as a method of performing a heat treatment below the NI transition point. Here, the NI transition point indicates the temperature at which the liquid crystal phase transitions to the isotropic phase.

  The thickness of the uncured reactive liquid crystal layer is preferably in the range of 1 nm to 1000 nm, more preferably in the range of 3 nm to 100 nm. This is because if the uncured reactive liquid crystal layer is thicker than the above range, it may be difficult to form an uncured reactive liquid crystal layer having excellent flatness. Further, if the thickness is smaller than the above range, the adhesive force between the spacer side substrate and the counter substrate may be lowered when the liquid crystal display element is formed.

  The reactive liquid crystal used in the step of forming the uncured reactive liquid crystal layer and other points are the same as those described in the section “A-1. Liquid crystal display element of the first aspect 1. Reactive liquid crystal layer”. Since it is the same, description here is abbreviate | omitted.

2. Liquid crystal display element substrate pair forming step Next, the crystal display element substrate pair forming step in this embodiment will be described. In the liquid crystal display element substrate pair forming step in this aspect, the first alignment film and the second alignment film are formed via an uncured reactive liquid crystal layer formed on either the spacer-side substrate or the counter substrate. The spacer side substrate and the counter substrate are brought into contact with each other, and then the reactive liquid crystal contained in the uncured reactive liquid crystal layer is fixed to bond the spacer side substrate and the counter substrate. This is a step of forming a liquid crystal display element substrate pair.

  In this step, as a method for fixing the reactive liquid crystal contained in the uncured reactive liquid crystal layer, the reactive liquid crystal can be fixed, and the spacer side is fixed as the reactive liquid crystal is fixed. There is no particular limitation as long as the method can bond the substrate and the counter substrate. Usually, since the reactive liquid crystal has a polymerizable liquid crystal material, a method of irradiating actinic radiation that activates the polymerization of the polymerizable liquid crystal material can be suitably used as such a method. In addition, actinic radiation here means the radiation which has the capability to cause superposition | polymerization with respect to polymeric liquid crystal material.

  The actinic radiation is not particularly limited as long as it is a radiation capable of polymerizing the polymerizable liquid crystal material, but usually ultraviolet light or visible light is used from the viewpoint of the ease of the apparatus. Irradiation light having a wavelength of 150 to 500 nm, preferably 250 to 450 nm, and more preferably 300 to 400 nm is used.

  In this embodiment, it can be said that a preferable method is to irradiate a polymerizable liquid crystal material in which the photopolymerization initiator generates radicals with ultraviolet rays and radically polymerizes the polymerizable liquid crystal material with ultraviolet rays as active radiation. . This is because the method using ultraviolet rays as the actinic radiation is an already established technique, and therefore it can be easily applied to this embodiment including the photopolymerization initiator to be used.

  As the light source of this irradiation light, low pressure mercury lamp (sterilization lamp, fluorescent chemical lamp, black light), high pressure discharge lamp (high pressure mercury lamp, metal halide lamp), short arc discharge lamp (super high pressure mercury lamp, xenon lamp, mercury xenon) Lamp). In particular, the use of metal halide lamps, xenon lamps, high-pressure mercury lamps, etc. is recommended. The irradiation intensity is appropriately adjusted according to the composition of the reactive liquid crystal and the amount of photopolymerization initiator.

  Such irradiation with active radiation may be performed under a temperature condition in which the polymerizable liquid crystal material becomes a liquid crystal phase, or may be performed at a temperature lower than the temperature at which the liquid crystal phase is formed. This is because the alignment state of the polymerizable liquid crystal material once in the liquid crystal phase is not disturbed suddenly even if the temperature is lowered thereafter.

  Further, as a method for fixing the alignment state of the polymerizable liquid crystal material, in addition to the method of irradiating the active radiation, a method of polymerizing the polymerizable liquid crystal material by heating can be used. As the reactive liquid crystal used in this case, it is preferable that the polymerizable liquid crystal monomer contained in the reactive liquid crystal is thermally polymerized below the NI transition point of the reactive liquid crystal.

  Further, in this step, when forming the reactive alignment layer by curing the curable resin described above, a sealant made of uncured resin formed on at least one of the spacer side substrate and the counter substrate is simultaneously used. It may be cured to form a sealant between the spacer side substrate and the counter substrate. Thus, the manufacturing method of this invention can be simplified by forming the said reactive orientation layer and the said sealing compound simultaneously by a hardening process.

3. Liquid Crystal Layer Forming Step Next, the liquid crystal layer forming step will be described. The liquid crystal layer forming step is a step of forming a liquid crystal layer made of a ferroelectric liquid crystal between the spacer side substrate and the counter substrate of the liquid crystal display element substrate pair formed by the liquid crystal display element substrate pair forming step. .

  In this step, a liquid crystal layer can be formed by injecting ferroelectric liquid crystal between the spacer side substrate of the liquid crystal display element substrate pair and the counter substrate. The method for injecting the ferroelectric liquid crystal in this step is not particularly limited, and a method generally used as a method for producing a liquid crystal cell can be used. For example, a method of forming an isotropic liquid by heating a composition for forming a liquid crystal layer containing a ferroelectric liquid crystal and then injecting it using the capillary effect and sealing with an adhesive can be used. The ferroelectric liquid crystal can be arranged by slowly cooling after injecting the liquid crystal layer forming composition.

  In addition, about the other point regarding the ferroelectric liquid crystal used for the said composition for liquid crystal layer formation, and a liquid crystal layer, what was described in the said "A-1. Liquid crystal display element of a 1st aspect 4. Liquid crystal layer" section. The description is omitted here.

4). Others About the drive method and use of the liquid crystal display element obtained by the manufacturing method of the liquid crystal display element which concerns on this aspect, it is the same as what was described in the above-mentioned "A-1. Liquid crystal display element of 1st aspect 5. Others." Therefore, the description here is omitted.

B-2. Next, a method for manufacturing the liquid crystal display element of the second aspect of the present invention will be described. A method for manufacturing a liquid crystal display element according to a second aspect includes a first substrate, a first electrode formed on the first substrate, a spacer formed on the first electrode, the first electrode, and the spacer. A spacer side substrate having a first alignment film formed thereon, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode A method of manufacturing a liquid crystal display element using a counter substrate having:
An uncured reactive liquid crystal layer forming step of forming an uncured reactive liquid crystal layer containing reactive liquid crystals having different compositions on the first alignment film and the second alignment film;
The uncured reactive liquid crystal layer formed on the first alignment film by the uncured reactive liquid crystal layer forming step and the uncured reactive liquid crystal layer formed on the second alignment film are brought into contact with each other. Then, by fixing the reactive liquid crystal, the spacer-side substrate and the counter substrate are bonded to form a liquid crystal display element substrate pair,
A liquid crystal layer forming step of forming a liquid crystal layer made of a ferroelectric liquid crystal between the spacer side substrate and the counter substrate of the liquid crystal display element substrate pair formed by the liquid crystal display element substrate pair forming step. It is characterized by this.

Next, the manufacturing method of this aspect is demonstrated, referring a figure. FIG. 6 is a process diagram showing an example of the manufacturing method of this embodiment. As shown in FIG. 6, in the manufacturing method of this aspect, first, a first substrate 1a, a first electrode 2a formed on the first substrate 1a, a spacer 4 formed on the first electrode 2a, The spacer-side substrate 11 having the first electrode 2a and the first alignment film 3a formed on the spacer 4, the second substrate 1b, and the second electrode 2b formed on the second substrate 1b And a counter substrate 12 having the second alignment film 3b formed on the second electrode 2b is prepared (FIG. 6A).
Next, uncured reactive liquid crystal layers (5a ′, 5b ′) containing reactive liquid crystals having different compositions are formed on the first alignment film 1a and the second alignment film 2a (uncured reaction). Liquid crystal layer forming step: (FIG. 6B).
Next, the uncured reactive liquid crystal layer 5a formed on the first alignment film 3a and the uncured reactive liquid crystal layer 5b formed on the second alignment film 3b are brought into contact with each other. Then, by fixing the reactive liquid crystal, the spacer-side substrate and the counter substrate are bonded to form a liquid crystal display element substrate pair 30 (liquid crystal display element substrate pair forming step (FIG. 6C). ).
Next, after injecting a liquid crystal layer made of ferroelectric liquid crystal between the spacer side substrate 11 and the counter substrate 12 of the liquid crystal display element substrate pair 30, the liquid crystal layer 6 is sealed with a sealant 7. (Liquid crystal layer forming step: FIG. 6D). In this embodiment, a liquid crystal display element is manufactured by the above process.

  According to the method for manufacturing a liquid crystal display element of this aspect, the uncured reactive liquid crystal layer is formed on the first alignment film and the second alignment film, so that the alignment film alone is used. A liquid crystal display element in which the orientation of the ferroelectric liquid crystal is controlled can be obtained. Moreover, the reactive liquid crystal contained in the uncured reactive liquid crystal layer formed on the first alignment film, and the reactive liquid crystal contained in the uncured reactive liquid crystal layer formed on the second alignment film. In order to obtain a liquid crystal display that can suppress the occurrence of alignment defects such as zigzag defects, hairpin defects, and double domains, and can realize a monostable operation mode using a ferroelectric liquid crystal. Can do.

  Hereinafter, the manufacturing method of the liquid crystal display element of this aspect is demonstrated.

1. Uncured reactive liquid crystal layer forming step In the present embodiment, the uncured reactive liquid crystal layer forming step includes reactivities of different compositions on the first alignment film of the spacer side substrate and the second alignment film of the counter substrate. This is a step of forming an uncured reactive liquid crystal layer containing an uncured reactive liquid crystal containing liquid crystal. The uncured reactive liquid crystal layer forming step in this embodiment includes forming an uncured reactive liquid crystal layer on the spacer side substrate and the counter substrate, and including the uncured reactive liquid crystal layer formed on the spacer side substrate. This is different from the method for manufacturing the liquid crystal display element of the first aspect in that the composition of the reactive liquid crystal and the composition of the reactive liquid crystal contained in the uncured reactive liquid crystal layer formed on the counter substrate are different.

  In the uncured reactive liquid crystal layer forming step in this aspect, the method for forming the uncured reactive liquid crystal layer on the first alignment film of the spacer-side substrate and the second alignment film of the counter substrate is the above-mentioned “B 1. Manufacturing method of liquid crystal display element of first embodiment 1. Since it is the same as that described in the section of “Uncured reactive liquid crystal layer forming step”, description here is omitted.

  Further, the spacer side substrate forming step for forming the spacer side substrate used in the present embodiment and the counter substrate forming step for forming the counter substrate used in the present embodiment include the above-mentioned “B-1. Liquid crystal display element of the first embodiment”. Since it is the same as that described in the section of “Manufacturing Method”, description thereof is omitted here.

2. Others The liquid crystal display element substrate pair forming step and the liquid crystal layer forming step in this aspect are the same as those described in the above section “B-1. Method for producing liquid crystal display element in first aspect”. Description of is omitted.

  About the drive method and use of the liquid crystal display element obtained by the manufacturing method of the liquid crystal display element which concerns on this aspect, it is the same as that of what was described in the said "A-1. Liquid crystal display element of 1st aspect 6. Others". Therefore, the description here is omitted.

  In addition, this invention is not limited to the said embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be specifically described with reference to examples.

(1) Example 1
(Production of spacer)
A photosensitive resin material (NN780 manufactured by JSR Corporation) is spin-coated (2000 rpm) on an ITO thin film of a glass substrate (100 mm × 100 mm × 0.7 mm) having an indium tin oxide (ITO) thin film formed on two surfaces. For 10 seconds), vacuum drying, and drying at 90 ° C. for 3 minutes on a hot plate. Thereafter, patterning was performed in a stripe shape having a width of 10 μm and a pitch of 1 mm by a photolithography method, followed by baking at 230 ° C. for 30 minutes. Thus, a spacer having a height of 1.5 μm was formed on the ITO thin film of the glass substrate on one substrate.

  Next, a solution obtained by dissolving Compound I represented by the following formula in cyclopentanone (2% by mass) on the substrate is applied by spin coating (1500 rpm, 15 seconds), and dried on a hot plate at 130 ° C. for 10 minutes. Was done. Then, 100 mJ exposure was carried out with polarized ultraviolet light, the photo-alignment process was performed, and the spacer side board | substrate and the opposing board | substrate were produced.

  A solution obtained by dissolving compound II represented by the following formula in cyclopentanone (5 mass%) on the second alignment film of the counter substrate was laminated by spin coating (1500 rpm, 15 seconds), and then heated at 55 ° C. on a hot plate. After drying for 3 minutes, a UV curable sealant (LCB610: EHC) was applied to one substrate with a seal dispenser.

Next, the substrate was assembled in parallel with the polarized UV irradiation direction, and exposed to 1000 mJ / cm ^{2 of} non-polarized ultraviolet rays at 25 ° C. while applying pressure. Use "R2301" (manufactured by AZ Electronic Materials) as the liquid crystal, attach the liquid crystal to the top of the injection port, and inject using the oven at a temperature 10 to 20 ° C higher than the nematic phase-isotropic phase transition temperature. Slowly returned to room temperature.

  The liquid crystal display device thus produced was placed under the crossed Nicols of the polarizing plate, and when the center of the display unit was pushed with a load of 100 g with a bar having a tip diameter of 1 cm, a change in display color or liquid crystal alignment was made around the bar tip. There was no disturbance.

(2) Comparative Example A photosensitive resin material (NN780, manufactured by JSR Corporation) was placed on an ITO thin film of a glass substrate (100 mm × 100 mm × 0.7 mm) having an indium tin oxide (ITO) thin film formed on two surfaces. The coating was applied by a spin coating method (2000 rpm, 10 seconds), vacuum drying was performed, and drying was performed at 90 ° C. for 3 minutes on a hot plate. Thereafter, patterning was performed in a stripe shape having a width of 10 μm and a pitch of 1 mm by a photolithography method, followed by baking at 230 ° C. for 30 minutes. Thus, a spacer having a height of 1.5 μm was formed on the ITO thin film of the glass substrate on one substrate.

  Next, a solution obtained by dissolving Compound I represented by the above formula in cyclopentanone (2% by mass) on the substrate is applied by spin coating (1500 rpm, 15 seconds), and dried on a hot plate at 130 ° C. for 10 minutes. Was done. Then, 100 mJ exposure was carried out with polarized ultraviolet light, the photo-alignment process was performed, and the spacer side board | substrate and the counter substrate were formed.

Next, a UV curable sealant (LCB610: EHC) was applied to one substrate with a seal dispenser. The substrate was assembled in a state parallel to the polarized UV irradiation direction, and exposed to 1000 mJ / cm ^{2 of} non-polarized ultraviolet light at 55 ° C. while applying pressure. Use "R2301" (manufactured by AZ Electronic Materials) as the liquid crystal, attach the liquid crystal to the top of the injection port, and inject using the oven at a temperature 10 to 20 ° C higher than the nematic phase-isotropic phase transition temperature. Slowly returned to room temperature.

  When the liquid crystal display device thus fabricated was placed under the crossed Nicols of the polarizing plate and the center of the display unit was pushed with a load having a tip diameter of 1 cm with a load of 100 g, a change in display color appeared around the bar tip, Disruption of the order of liquid crystal alignment occurred.

(3) Example 2
A liquid crystal display device was produced in the same manner as in Example 1 except that the compound II was changed to Adeka Kiracol PLC-7209 (manufactured by Asahi Denka Kogyo Co., Ltd.).
When this liquid crystal display element was placed under the crossed Nicols of a polarizing plate and the center of the display part was pushed with a load having a tip diameter of 1 cm and a load of 100 g, a change in display color and disorder of liquid crystal orientation were observed around the bar tip. There wasn't.

(4) Example 3
A liquid crystal display device was produced in the same manner as in Example 1 except that the compound II was changed to Adeka Kiracol PLC-7183 (Asahi Denka Kogyo Co., Ltd.).
When this liquid crystal display element was placed under the crossed Nicols of a polarizing plate and the center of the display part was pushed with a bar having a tip diameter of 1 cm with a load of 100 g, a change in display color and disorder of liquid crystal alignment were observed around the bar tip. There wasn't.

(5) Example 4
The spacer side substrate and the counter substrate were formed by the same method as in Example 1 above. Next, a solution in which Adeka Kiracol PLC-7209 (manufactured by Asahi Denka Kogyo Co., Ltd.) is dissolved in cyclopentanone (5% by mass) on the first alignment film of the spacer side substrate is spin-coated (1500 rpm, 15 seconds). And dried on a hot plate at 55 ° C. for 3 minutes. On the other hand, a solution prepared by dissolving Adeka Kiracol PLC-7183 (manufactured by Asahi Denka Kogyo Co., Ltd.) in cyclopentanone (5 mass%) on the second alignment film of the counter substrate is laminated by spin coating (1500 rpm, 15 seconds). And dried on a hot plate at 55 ° C. for 3 minutes.
A UV curable sealant (LCB610: EHC) was applied to one of the spacer side substrate and the counter substrate with a seal dispenser. The substrate was assembled parallel to the polarized UV irradiation direction, and exposed to 1000 mJ / cm ^{2 of} non-polarized ultraviolet light at 55 ° C. while applying pressure. Use "R2301" (manufactured by AZ Electronic Materials) as the liquid crystal, attach the liquid crystal to the top of the injection port, and inject using the oven at a temperature 10 to 20 ° C higher than the nematic phase-isotropic phase transition temperature. Slowly returned to room temperature.
When this liquid crystal panel was placed under the crossed Nicols of a polarizing plate and the center of the display unit was pushed with a load of 100 g with a bar with a tip diameter of 1 cm, no change in display color or disorder of liquid crystal alignment was observed around the bar tip. It was.

It is a schematic sectional drawing which shows an example of the liquid crystal display element of this invention. It is a schematic sectional drawing which shows an example of the spacer side board | substrate used for the liquid crystal display element of this invention. It is a schematic plan view which shows the other example of the spacer side board | substrate used for the liquid crystal display element of this invention. It is a schematic sectional drawing which shows the other example of the liquid crystal display element of this invention. It is process drawing which shows an example of the manufacturing method of the liquid crystal display element of this invention. It is process drawing which shows the other example of the manufacturing method of the liquid crystal display element of this invention. It is the graph which showed the change of the transmittance | permeability with respect to the applied voltage of a ferroelectric liquid crystal. It is the figure which showed the difference in orientation by the difference in the phase sequence which a ferroelectric liquid crystal has. It is the photograph which showed the double domain which is the orientation defect of a ferroelectric liquid crystal. It is a schematic diagram which shows the behavior of a liquid crystal molecule.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... 1st board | substrate 1b ... 2nd board | substrate 2a ... 1st electrode 2b ... 2nd electrode 3a ... 1st alignment film 3b ... 2nd alignment film 4 ... Spacer 51, 52 ... Reactive liquid crystal layer 5 ', 5a', 5b '... Uncured reactive liquid crystal layer 6 ... Liquid crystal layer 7 ... Sealing agent 8a, 8b ... Polarizing plate 10a, 10b ... Liquid crystal display element 11 ... Spacer side substrate 12 ... Counter substrate

Claims (11)

A first substrate; a first electrode formed on the first substrate; a spacer formed on the first electrode; and a first alignment film formed on the first electrode and the spacer. A counter substrate having a spacer-side substrate, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode is used as the first alignment film. And a liquid crystal display element that is disposed so as to face the second alignment film, and a liquid crystal layer made of a ferroelectric liquid crystal is sandwiched between the spacer-side substrate and the counter substrate,
A reactive liquid crystal layer formed by fixing a reactive liquid crystal expressing a nematic phase in a state having liquid crystal regularity is formed only on either the first alignment film or the second alignment film, And the said spacer side board | substrate and the said opposing board | substrate are adhere | attached through the said reactive liquid crystal layer,
The ferroelectric liquid crystal has a phase sequence that does not pass through the smectic A phase, exhibits half-V-shaped switching characteristics, is mono-stabilized, and can display gradations by changing the voltage. And
Furthermore, the ferroelectric liquid crystal exhibits monodomain alignment in the liquid crystal layer. The liquid crystal display element according to claim 1, wherein the reactive liquid crystal includes a polymerizable liquid crystal monomer. The liquid crystal display element according to claim 2 , wherein the polymerizable liquid crystal monomer is a monoacrylate monomer or a diacrylate monomer. The liquid crystal display element according to claim 3 , wherein the diacrylate monomer is a compound represented by the following formula (1).

(Here, X is hydrogen, alkyl having 1 to 20 carbon atoms, alkenyl having 1 to 20 carbon atoms, alkyloxy having 1 to 20 carbon atoms, alkyloxycarbonyl having 1 to 20 carbon atoms, formyl, carbon Represents an alkylcarbonyl having 1 to 20 carbon atoms, an alkylcarbonyloxy having 1 to 20 carbon atoms, halogen, cyano or nitro, and m represents an integer within the range of 2 to 20.) The liquid crystal display element according to claim 3 , wherein the diacrylate monomer is a compound represented by the following formula (2).

(Wherein Z ²¹ and Z ²² in the formula are each independently directly bonded —COO—, —OCO—, —O—, —CH ₂ CH ₂ —, —CH═CH—, —C Represents ≡C—, —OCH ₂ —, —CH ₂ O—, —CH ₂ CH ₂ COO—, —OCOCH ₂ CH ₂ —, l and m represent 0 or 1, and n represents a range of 2 to 8 (In the formula, R represents hydrogen or alkyl having 1 to 5 carbon atoms.) The liquid crystal display element according to any one of claims 1 to 5, wherein the first alignment film and the second alignment film are photo-alignment films. The constituent material of the photo-alignment film is a photo-reactive material that imparts anisotropy to the photo-alignment film by causing a photoreaction, or anisotropy to the photo-alignment film by causing a photoisomerization reaction. The liquid crystal display element according to claim 6 , which is a photoisomerization type material containing a photoisomerization reactive compound to be imparted. The liquid crystal display element according to any one of claims 1 to 7 , further comprising a sealing agent made of an ultraviolet curable resin between the spacer side substrate and the counter substrate. The liquid crystal display element according to any one of claims 1 to 8 , wherein the liquid crystal display element is driven by an active matrix method using a thin film transistor. The liquid crystal display element according to any one of claims 1 to 9 , wherein the liquid crystal display element is driven by a field sequential color system. A first substrate; a first electrode formed on the first substrate; a spacer formed on the first electrode; and a first alignment film formed on the first electrode and the spacer. Manufacturing of a liquid crystal display device using a counter substrate having a spacer side substrate, a second substrate, a second electrode formed on the second substrate, and a second alignment film formed on the second electrode A method,
An uncured reactive liquid crystal layer forming step of forming an uncured reactive liquid crystal layer containing a reactive liquid crystal expressing a nematic phase only on either the first alignment film or the second alignment film;
The spacer side substrate and the counter substrate are brought into contact so that the first alignment film and the second alignment film face each other through the uncured reactive liquid crystal layer formed in the uncured reactive liquid crystal layer forming step. Then, the reactive liquid crystal is fixed in a state having liquid crystal regularity , thereby bonding the spacer side substrate and the counter substrate to form a liquid crystal display element substrate pair. Process,
The liquid crystal display element substrate pair forming step includes a phase sequence that does not pass through the smectic A phase between the spacer-side substrate and the counter substrate of the liquid crystal display element substrate pair, and a half V-shaped switching (half) After injecting a ferroelectric liquid crystal exhibiting -V shaped switching) characteristics, the ferroelectric liquid crystal is aligned by slow cooling, and a liquid crystal layer in which the ferroelectric liquid crystal is mono-stabilized and exhibits monodomain alignment A liquid crystal layer forming step to be formed;
And a liquid crystal display element capable of gradation display by voltage change.

Images