JP2007010888A - Liquid crystal device, method for manufacturing liquid crystal device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device in which moisture absorption and moisture intrusion are prevented, a method for manufacturing the same, and further, an electronic appliance that uses the same. <P>SOLUTION: The liquid crystal device 60 comprises a liquid crystal interposed between a pair of substrates 10, 20 placed facing each other. A sealing material 19 is arranged on respective inside faces of the pair of substrates 10, 20 with the liquid crystal enclosed therein. The sealing material 19 is formed by arranging a sol-gel solution containing a silane coupling agent, a metal alkoxide, and water between the substrates 10, 20 and hardening it. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid crystal device, a method for manufacturing a liquid crystal device, and an electronic apparatus.

  A liquid crystal device used as a light modulation means mounted on a liquid crystal projector or the like or a direct-view display device mounted on a mobile phone or the like mainly includes a pair of substrates having electrodes for applying a voltage to a liquid crystal layer. Has been. A conductive film (pixel electrode, counter electrode, etc.) and an alignment film for controlling the initial alignment state of liquid crystal molecules are formed on the inner surfaces of the pair of substrates constituting the liquid crystal device. The alignment films are bonded by a sealing material made of an organic material such as a resin so that the substrates are bonded together, and liquid crystal is sealed in a region surrounded by the sealing material. .

By the way, in the liquid crystal device, moisture absorption and moisture intrusion cause deterioration in quality, and therefore, a technique for performing water repellency treatment on the surface of the alignment film or forming a film having water repellency on the surface of the alignment film is provided. ing.
JP 2002-202509 A

  However, in the technique of forming a water repellent film on the surface of the alignment film, the pretilt of the liquid crystal element is disturbed due to the non-uniform thickness of the water repellent film, or bubbles are generated in the liquid crystal layer due to contact with the water repellent film. May cause problems such as the occurrence of

Even if the surface of the alignment film is subjected to water repellent treatment in this way, the moisture permeability of the organic material sealing material itself is relatively high, for example, about 5 g / m ² · 24 hr. Moisture permeation (moisture absorption) occurs from the side surfaces and also from the interface between the sealing material and the alignment film, and moisture penetrates into the liquid crystal device, resulting in degradation of quality.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid crystal device capable of preventing moisture absorption and moisture intrusion, a method for manufacturing the same, and an electronic apparatus using the liquid crystal device.

In order to achieve the above object, a liquid crystal device of the present invention is a liquid crystal device in which liquid crystal is sandwiched between a pair of substrates facing each other,
A sealing material is provided between the inner surfaces of the pair of substrates in a state where the liquid crystal is sealed,
The sealing material is characterized in that a sol-gel solution containing a silane coupling material, a metal alkoxide, and water is disposed between the substrates and cured.

  The sealing material made of a sol-gel solution containing a silane coupling material, a metal alkoxide, and water is different from a conventional organic material, and has a polysiloxane bond by a silane coupling material or a metal by a metal alkoxide. By containing the organic-inorganic hybrid polymer contained, the film density is increased, the moisture permeability is sufficiently low, and the adhesion to the ground is excellent. Therefore, according to this liquid crystal device, the sealing material is provided between the pair of substrates and the pair of substrates are bonded to each other. Quality degradation due to water ingress is prevented.

In the liquid crystal device, the metal alkoxide is preferably composed of at least one of Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide.
In this way, Zr, Al, Ti, and Mg in these metal alkoxides become, for example, oxides, and are bonded to the polysiloxane skeleton formed by the silane coupling material, or the inner surface side of the substrate that is the base of the sealing material Accordingly, the film density of the obtained sealing material is increased, moisture permeability (hygroscopicity) is decreased, and moisture resistance is increased. Moreover, since the adhesiveness of the sealing material with respect to the base is increased, the moisture-proof effect is ensured over a long period of time, and the reliability is improved.

In the liquid crystal device, the silane coupling material preferably includes a plurality of types of alkoxysilanes, and these alkoxysilanes preferably have different numbers of carbon atoms in the respective alkoxy groups.
Thus, if the number of carbons in each alkoxy group of a plurality of types of alkoxysilanes is different from each other, particularly when these are composed of a long chain with a large number of carbons and a short chain with a small number of carbons, When the short chain enters the structure, the film density of the sealing material becomes higher, the moisture permeability becomes lower, and the moisture resistance becomes higher.

In the liquid crystal device, the sol-gel solution contains a water-repellent material having a water-repellent group, and the sealing material obtained by curing the sol-gel solution has water repellency. Is preferred.
In this way, the water repellency of the sealing material prevents water from adhering to the sealing material, so that the sealing material is prevented from easily causing moisture permeation due to such water adhesion. . In addition, it is of course possible to prevent moisture from entering the liquid crystal device due to moisture adhesion.

In the liquid crystal device, it is preferable that a recess is formed on the inner surface side of at least one of the pair of substrates, and the sealing material is formed in a state of filling the recess.
In this way, even if the viscosity of the sol-gel solution is relatively low and has a certain degree of fluidity, the sealing material is predetermined by filling the concave portion with the sol-gel solution and curing it. It will be arranged well at the position of.

In this liquid crystal device, an alignment film is formed on the inner surface side of the one substrate, and the recesses are formed on the surface of the alignment film, reflecting the concave shape formed on the substrate side as a base. It is preferable.
In this way, it is possible to easily form a recess with respect to the surface of the alignment film. In addition, even when the alignment film is thin, the concave portion is not directly formed on the alignment film. Therefore, it is possible to prevent a defective portion from being generated in the film by forming the concave portion directly.

In the liquid crystal device, a concave portion is formed on the inner surface side of one of the pair of substrates, and the convex portion fits in the concave portion on the inner surface side of the other substrate of the pair of substrates. It is preferable that the sealing material is formed in a state where the space between the concave portion and the convex portion fitted in the concave portion is filled.
In this way, even if the viscosity of the sol-gel solution is relatively low and has a certain degree of fluidity, the sol-gel solution is placed in the recess and cured here to obtain a sealing material. It will be well placed in position.
Moreover, since the sealing material is formed in a state in which the space between the concave portion and the convex portion is filled, the sealing material has an inner surface side from the outer surface side as compared with the case where there is no concave portion and convex portion as in the prior art. Therefore, the possibility of moisture and the like entering the liquid crystal layer through the sealing material or the interface between the sealing material and the base is reduced.
Furthermore, if the height of the convex portion is sufficiently long with respect to the depth of the concave portion and the difference is made substantially equal to the cell gap, the cell gap can be defined by the fitting of the concave portion and the convex portion. This can eliminate the need for a gap material.

In this liquid crystal device, an alignment film is formed on each inner surface side of the pair of substrates, and the surface of these alignment films reflects a concave shape or a convex shape formed on the substrate side as a base. Thus, it is preferable that the concave portion or the convex portion is formed.
In this way, it is possible to easily form a recess with respect to the surface of the alignment film. In addition, even when the alignment film is thin, the concave portion is not directly formed on the alignment film. Therefore, it is possible to prevent a defective portion from being generated in the film by forming the concave portion directly.

The liquid crystal device manufacturing method of the present invention is a liquid crystal device in which a sealing material is provided between a pair of substrates facing each other, and a liquid crystal layer is sealed with the sealing material,
Applying a sol-gel solution containing a silane coupling material, a metal alkoxide, and water to at least one of the pair of substrates;
Making the pair of substrates face each other through the sol-gel solution;
And a step of curing the sol-gel solution to form a sealing material, and bonding the pair of substrates with the sealing material.

  According to this method of manufacturing a liquid crystal device, a pair of substrates are bonded together by the sealing material that becomes the organic / inorganic hybrid polymer, and the liquid crystal layer is sealed by the sealing material. Intrusion of water is remarkably prevented, which makes it possible to prevent deterioration in quality due to moisture absorption and water intrusion.

An electronic apparatus according to the present invention includes the above-described liquid crystal device.
According to this electronic device, since the liquid crystal device in which deterioration due to moisture absorption or water intrusion is prevented is provided, the electronic device itself is also prevented from deterioration in quality, and the display reliability is improved. .

Hereinafter, the present invention will be described in detail with reference to the drawings. In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.
(First embodiment)
First, a liquid crystal device according to a first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the liquid crystal device of the present invention is applied to an active matrix transmission type liquid crystal device using a thin film transistor (hereinafter referred to as TFT) element as a switching element.

  As shown in FIG. 6, in the liquid crystal device 60 of the first embodiment, a sealing material 19 is annularly arranged at the peripheral edge between the pair of substrates 10 and 20, and the liquid crystal is disposed at the center, that is, inside the sealing material 19. And the liquid crystal layer 50 is sealed. The substrate 10 is formed by forming a transparent conductive layer (transparent electrode) (not shown) on the inner surface of the substrate body 10A, and further forming the inorganic alignment film 16 thereon. Similarly, the substrate 20 is formed of the substrate body 20A. A transparent conductive layer (transparent electrode) (not shown) or the like is formed on the inner surface, and an inorganic alignment film 22 is further formed thereon. An annular protrusion 81 is formed on the surface of the substrate body 10A constituting the substrate 10, and the convex shape of the protrusion 81 of the substrate body 10A serving as the base is reflected on the inorganic alignment film 16. An annular convex portion 82 is formed. The substrate body 20A constituting the substrate 20 has an annular groove 91 formed on the surface thereof, and the inorganic alignment film 22 reflects the concave shape of the groove 91 of the substrate body 20A serving as the base. An annular recess 92 is formed.

  The convex portions 82 and the concave portions 92 are fitted via the seal material 19 when the substrate 10 and the substrate 20 are opposed to each other. That is, the sealing material 19 is formed in a state in which a space between the concave portion 92 and the convex portion 82 fitted in the concave portion 92 is filled, thereby sealing the liquid crystal layer 50 and the substrates 10 and 20. The inner surfaces, that is, the inorganic alignment films 16 and 22 are sealed, and the substrates 10 and 20 are bonded together.

Here, unlike the conventional organic material, the sealing material 19 is made of an organic / inorganic hybrid polymer that has extremely low moisture permeability and high adhesion.
That is, the sealing material 19 is formed by placing a sol-gel solution containing a silane coupling material, a metal alkoxide, and water at a desired position and curing it. As the silane coupling material, one or more selected from various alkoxysilanes and acryloxysilanes are used. Specifically, tetramethoxysilane, 3-glycidoxyproyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, N-trimethoxysilylpropyl-N N, N-trimethylammonium chloride, methacryloxypropyltrimethoxysilane, etc. are preferably used.

  Here, in particular, when a plurality of types of silane coupling materials, for example, a plurality of types of alkoxysilanes are used, it is preferable to use those alkoxysilanes having different numbers of carbon atoms in the respective alkoxy groups. An alkoxysilane having an alkoxy group (alkyl group) having a large number of straight carbon atoms and a long chain, and an alkoxy group (alkyl group) having a small number of straight carbon atoms and a short chain. It is preferable to use a mixture with alkoxysilane. If such a plurality of types of alkoxysilanes are used, the short chain enters the network structure of long chains as described later, thereby increasing the film density of the resulting sealing material 19 and reducing its moisture permeability. The moisture resistance of the sealing material 19 can be further improved.

  Moreover, as a metal alkoxide, Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide are suitable, and the 1 type or multiple types selected from these are used suitably. Specifically, aluminum-sec-butoxide, zirconium-n-propoxide, and the like are preferable. The sol-gel solution in the present invention is added to the mixture of the silane coupling material and the metal alkoxide by adding water necessary to hydrolyze them and performing appropriate treatment such as stirring at an appropriate temperature. It is said.

In the present embodiment, the sealing material 19 has water repellency. This is because the sol-gel solution is formed to contain a water-repellent material having a water-repellent group, so that the sealing material 19 obtained by curing the sol-gel solution has water repellency. -ing
Here, the water repellent material may be newly added to these materials as materials other than the silane coupling material and metal alkoxide, or the silane coupling material or metal alkoxide itself may be added. Alternatively, a water repellent material may be used. That is, a water-repellent material may be added to the silane coupling material and metal alkoxide to form a sol-gel solution, or a silane coupling material or metal alkoxide having water repellency may be used. A sol-gel solution may be formed.

  When a water repellent material is newly added as a material other than the silane coupling material and the metal alkoxide, examples of the water repellent material include a silane compound, a surfactant, and the like between the seal surfaces (the arrangement surface of the seal material 19). A film that forms an organic thin film composed of organic molecules and imparts water repellency is used. The organic molecules for water repellency between the seal surfaces are modified by modifying the surface properties of the substrate on the opposite side to the functional group that can be physically or chemically bonded to the substrate forming the seal surface. It has a functional group that makes liquid repellency (controlling the surface energy), and is bonded to a substrate to form an organic thin film, ideally a monomolecular film. In particular, organic molecules in which the organic structure that connects the functional group that can bind to the base material and the functional group on the opposite side of the functional group is a linear or partially branched carbon chain of carbon binds to the base material and self-assembles. This is preferable.

As such a self-organizing compound, that is, the water repellent material, for example, a silane compound represented by the following general formula (1) can be used. In formula (1), R ¹ represents an organic group, X ¹ and X ² represent —OR ² (alkoxy group), —R ² (alkyl group), —Cl (chlorine group), and X ¹ and X ² R ² contained in 1 represents an alkyl group having 1 to 4 carbon atoms, and a represents an integer of 1 to 3.
R ¹ SiX ¹ _a X ² _(3-a) (1)

  In the silane compound represented by the general formula (1), an organic group is substituted on the silane molecule, and an alkoxy group, an alkyl group, or a chlorine group is substituted on the remaining bonding group. In particular, the silane compound having an alkoxy group is an alkoxy silane serving as the silane coupling material constituting the sol-gel solution in the present invention, and therefore, as described above, when it is desired to impart water repellency to the silane coupling material. In this case, an alkoxysilane represented by the general formula (1) may be used.

Examples of the organic group R ¹ include, for example, phenyl group, benzyl group, phenethyl group, hydroxyphenyl group, chlorophenyl group, aminophenyl group, naphthyl group, anthrenyl group, pyrenyl group, thienyl group, pyrrolyl group, cyclohexyl group, cyclohexane Hexenyl, cyclopentyl, cyclopentenyl, pyridinyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, octadecyl, n- Octyl group, chloromethyl group, methoxyethyl group, hydroxyethyl group, aminoethyl group, cyano group, mercaptopropyl group, vinyl group, allyl group, acryloxyethyl group, methacryloxyethyl group, glycidoxypropyl group, acetoxy group Etc. can be illustrated.
The alkoxy group and chlorine group of X ¹ and X ² are functional groups for forming a Si—O—Si bond and the like, and are hydrolyzed by water and eliminated as alcohol or acid. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group.
The carbon number of R ² is in the range of 1 to 4 from the viewpoint that the molecular weight of the alcohol to be desorbed is relatively small, can be easily removed, and the deterioration of the denseness of the formed film (sealing material 19) can be suppressed. It is preferable.

A typical water-repellent silane compound represented by the general formula (1) includes a fluorine-containing alkylsilane compound. In particular, R ¹ has a structure represented by the perfluoroalkyl structure C _n F _{(2n + 1)} , and examples thereof include compounds represented by the general formula (2). In the formula (2), n represents an integer of 1 to 18, m represents an integer of 2 to 6, and X ^1, X ² and a represent the same meaning as in the formula (1).
By using the fluorine-containing alkylsilane compound, each compound is oriented so that the fluoroalkyl group is located on the surface of the resulting sealing material 19 and a self-assembled film is formed. Can be granted.
_{C n F (2n + 1)} (CH 2) m SiX 1 a X 2 (3-a) ... (2)

More specifically, CF ₃ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₃ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ (CF ₂ ) ₇ —CH ₂ CH ₂ —Si (OCH ₃₎ ) ₃ , CF ₃ (CF ₂ ) ₁₁ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ (CF ₂ ) ₃ —CH ₂ CH ₂ —Si (CH ₃ ) (OCH ₃ ) ₂ , CF _{3 (CF 2) 7 -CH 2} CH 2 -Si (CH 3) (OCH 3) 2, CF 3 (CF 2) 8 -CH 2 CH 2 -Si (CH 3) (OC 2 H 5) 2, CF ₃ (CF ₂ ) ₈ —CH ₂ CH ₂ —Si (C ₂ H ₅ ) (OC ₂ H ₅ ) _{2 and the} like.

Further, ^{R 1} Gapa - perfluoroalkyl ether structure _{C n F (2n + 1)} O p F can also be mentioned those having a structure represented by 2p _{O r.} Specific examples thereof include a compound represented by the following general formula (3).
_{C p F (2p + 1)} O (C p F 2p O) r (CH 2) m SiX 1 a X 2 (3-a) ... (3)

In Formula (3), m represents an integer of 2 to 6, p represents an integer of 1 to 4, r represents an integer of 1 to 10, and X1, X2, and a represent the same meaning as described above.
Specific examples of the compound include CF ₃ O (CF ₂ O) ₆ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ O (C ₃ F ₆ O) ₄ —CH ₂ CH ₂ —. _{Si (OCH 3) 3, CF} 3 O (C 3 F 6 O) 2 (CF 2 O) 3 -CH 2 CH 2 -Si (OCH 3) 3, CF 3 O (C 3 F 6 O) 8 -CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ O (C ₄ F ₉ O) ₅ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ O (C ₄ F ₉ O) ₅ —CH ₂ CH _{2 -Si (CH 3) (OC} 2 H 5) 2, CF 3 O (C 3 F 6 O) 4 -CH 2 CH 2 -Si (C 2 H 5) (OCH 3) 2 , and the like.

  Silane compounds having a fluoroalkyl group or a perfluoroalkyl ether structure are collectively referred to as “FAS”. These compounds may be used alone or in combination of two or more. By using FAS, it is possible to obtain adhesion with the seal surface and good water repellency.

Further, as the water repellent material, a surfactant represented by the following general formula (4) can also be used. In Formula (4), R ¹ represents a hydrophobic organic group, Y ¹ represents a hydrophilic polar group, —OH, — (CH ₂ CH ₂ O) _n H, —COOH, —COOA, —CONH ₂ , —SO ₃ H, —SO ₃ A, —OSO ₃ H, —OSO ₃ A, —PO ₃ H ₂ , —PO ₃ A, —NO ₂ , —NH ₂ , —NH ₃ B (ammonium salt), ≡NHB (Pyridinium salt), -NX13B (alkyl ammonium salt) and the like. However, A represents one or more cations, and B represents one or more anions. X1 represents the same alkyl group having 1 to 4 carbon atoms as described above.
R ¹ Y ¹ (4)

The surfactant represented by the general formula (4) is a compound in which a hydrophilic functional group is bonded to a lipophilic organic group R ¹ . Y ¹ represents a hydrophilic polar group, which is a functional group for bonding or adsorbing to the base material, and the organic group R ¹ has lipophilicity and is arranged on the opposite side of the hydrophilic surface so as to be on the hydrophilic surface. A lipophilic surface is formed. Examples of the organic group R ¹ include, for example, phenyl group, benzyl group, phenethyl group, hydroxyphenyl group, chlorophenyl group, aminophenyl group, naphthyl group, anthrenyl group, pyrenyl group, thienyl group, pyrrolyl group, cyclohexyl group, cyclohexane Hexenyl, cyclopentyl, cyclopentenyl, pyridinyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, octadecyl, n- Octyl group, chloromethyl group, methoxyethyl group, hydroxyethyl group, aminoethyl group, cyano group, mercaptopropyl group, vinyl group, allyl group, acryloxyethyl group, methacryloxyethyl group, glycidoxypropyl group, acetoxy group Etc. can be illustrated.

A typical water-repellent surfactant represented by the general formula (4) includes a compound having a fluorine-containing alkyl structure. In particular, those having a structure in which R ¹ is represented by the perfluoroalkyl structure C _n F _{(2n + 1)} are useful. More _{specifically, F (CF 2 CF 2)} (1~7) -CH 2 CH 2 -N + (CH 3) 3 Cl -, C 8 F 17 SO 2 NHC 3 H 6 -N + (CH 3 ), F (CF ₂ CF ₂ ) _(1-7) —CH ₂ CH ₂ SCH ₂ CH ₂ —CO ₂ —Li ⁺ , C ₈ F ₁₇ SO ₂ N (C ₂ H ₅ ) —CO ₂ —K ⁺ , _{(F (CF 2 CF 2)} (1~7)) CH 2 CH 2 O) 1,2 PO (O - NH 4 +) 1,2, C 10 F 21 SO 3 - NH 4 +, C 6 F 13 _{CH 2 CH 2 SO 3 H,} C 6 F 13 CH 2 CH 2 SO 3 - NH 4 +, C 8 F 17 SO 2 N (C 2 H 5) - (CH 2 CH 2 O) (0~25) H _{, C 8 F 17 SO 2 N} (C 2 H 5) - (CH 2 CH 2 O) (0~25) CH _{, F (CF 2 CF 2)} (1~7) -CH 2 CH 2 O- (CH 2 CH 2 O) (0~25) H and the like.

The surfactant having a fluoroalkyl group may be used alone or in combination of two or more. In addition, adhesiveness with a base material and favorable water repellency can be obtained by using the surfactant which has a fluoroalkyl group.
Further, it may have a structure having an alkyl group that does not contain fluorine, and water repellency can be obtained by forming a dense film on a general surfactant.

Further, when the silane coupling material or the metal alkoxide itself is used as a water repellent material, the silane coupling material or metal alkoxide having such a water repellency is, for example, as described above, an alkoxy compound as a silane coupling material. Silane may be used. In order to further improve the water repellency, a fluorine group introduced into the alkoxy group of this alkoxysilane or the alkoxy group of the metal alkoxide, for example, a perfluoroalkyl structure [C _n F _{(2n + 1)} ] May be used. Further, even if no fluorine group is introduced, the sealing material 19 obtained by forming a hydrophobic group if the alkyl group in the alkoxy group has a large number of carbon atoms and the straight chain is sufficiently long. Has water repellency.

  A sol-gel solution formed by such a material, that is, a sol-gel solution formed by adding water to a mixture of a silane coupling material and a metal alkoxide and a water-repellent material added as necessary, for example, Formed in the sealing material 19 by filling the concave portion 92 of the substrate 20 and further fitting the convex portion 82 of the substrate 10 through the sol-gel solution into the concave portion 92, followed by curing treatment. Is done. When the sol-gel solution is filled and arranged in the concave portion 92 in this way, the substrate 20 is placed with the concave portion 92 facing upward, and the filling arrangement is performed in this state. By filling and arranging the sol-gel solution in the recess 92 in this way, the sol-gel solution is placed in the recess 92 at a desired position even if the viscosity of the sol-gel solution is lower than that of a conventional sealing material and has a certain degree of fluidity. Therefore, the sealing material 19 can be satisfactorily arranged at a predetermined position.

Here, in the present embodiment, as the sol-gel solution, the tetramethoxysilane, 3-glycidoxyproyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, aluminum-sec-butoxide, and zirconium-n-propoxide are mixed at an appropriate ratio, and these are mixed. By adding an equivalent amount of water to the mixture and stirring, a sol-gel solution having a relatively high viscosity and thus high tackiness is produced.
The arrangement of the sol-gel solution thus obtained is not particularly limited, and various methods can be employed. Specifically, various printing methods such as screen printing, and further, a dispensing method and an ink jet method are preferably used. In the present embodiment, the dispensing method and the ink jet method are more suitable because the filling is particularly performed in the recess 92 of the substrate 20.

When the sol-gel solution is filled and disposed in the recess 92 in this manner, the sol-gel solution is cured by irradiating the coated surface with ultraviolet rays for several seconds to 60 seconds, for example, and the sealing material 19 can be obtained. Alternatively, the sol-gel solution is cured to obtain the sealing material 19 by performing heat treatment for several minutes to several tens of minutes at a temperature of 150 ° C. or lower (for example, 80 ° C. to 150 ° C.) at which the characteristics of the liquid crystal device 60 are not deteriorated. You can also. Of course, the curing time can be further shortened by using such ultraviolet irradiation treatment and heat treatment in combination.
Prior to the formation of the sealing material 19, it is desirable that the inside of the concave portion 92 and the surface of the convex portion 82 be cleaned by an appropriate method.

Sealing material 19 obtained in this way is, for example, while the moisture permeability of the sealing material made of conventional organic materials is about ^5g / m 2 · 24hr, much about 0.16g ^/ m 2 · 24hr It became very low. Therefore, in the liquid crystal device 60 in which the substrates 10 and 20 are bonded together by the sealing material 19, moisture absorption and water ingress are remarkably prevented as compared with the prior art, thereby preventing deterioration in quality due to moisture absorption and water intrusion. It will be.

Next, each part of the liquid crystal device 60 will be described.
FIG. 1 is a plan view of a TFT array substrate in the liquid crystal device 60, and shows a specific configuration of the substrate 10 shown in FIG. An image production region 101 is formed in the center of the TFT array substrate (substrate) 10. The sealing material 19 is disposed on the periphery of the image production area 101, and a liquid crystal layer (not shown) is sealed in the image production area 101. This liquid crystal layer is formed by directly applying a liquid crystal on the TFT array substrate 10, and has a so-called sealing-less structure in which the sealing material 19 is not provided with a liquid crystal injection port. On the outside of the sealing material 19, a scanning line driving element 110 that supplies a scanning signal to a scanning line described later and a data line driving element 120 that supplies an image signal to a data line described later are mounted. A wiring 76 is routed from the driving elements 110 and 120 to the connection terminal 79 at the end of the TFT array substrate 10.

On the other hand, a common electrode 21 (see FIG. 4) is formed on the counter substrate 20 (see FIG. 4) bonded to the TFT array substrate 10. The common electrode 21 is formed over almost the entire image forming region 101, and inter-substrate conducting portions 70 are provided at the four corners. A wiring 78 is routed from the inter-substrate conduction portion 70 to the connection terminal 79.
Then, various signals input from the outside are supplied to the image production region 101 via the connection terminals 79, so that the liquid crystal device is driven.

(Equivalent circuit)
FIG. 2 is an equivalent circuit diagram of the liquid crystal device. Pixel electrodes 9 are respectively formed on a plurality of dots arranged in a matrix so as to form an image production region of the transmissive liquid crystal device. Further, a TFT element 30 which is a switching element for performing energization control to the pixel electrode 9 is formed on the side of the pixel electrode 9. A data line 6 a is connected to the source of the TFT element 30. Image signals S1, S2,..., Sn are supplied to the data lines 6a from the data line driving elements described above.

  A scanning line 3 a is connected to the gate of the TFT element 30. Scanning signals G1, G2,..., Gm are supplied to the scanning line 3a in a pulsed manner from the scanning line driving element described above at a predetermined timing. On the other hand, the pixel electrode 9 is connected to the drain of the TFT element 30. When the TFT elements 30 serving as switching elements are turned on for a certain period by the scanning signals G1, G2,..., Gm supplied from the scanning line 3a, the image signals S1, S2,. Sn is written to the liquid crystal of each dot via the pixel electrode 9 at a predetermined timing.

  The predetermined level image signals S1, S2,..., Sn written in the liquid crystal are held for a certain period by a liquid crystal capacitor formed between the pixel electrode 9 and a common electrode described later. In order to prevent leakage of the held image signals S1, S2,..., Sn, a storage capacitor 17 is formed between the pixel electrode 9 and the capacitor line 3b, and is arranged in parallel with the liquid crystal capacitor. . Thus, when a voltage signal is applied to the liquid crystal, the alignment state of the liquid crystal molecules changes depending on the applied voltage level. Thereby, the light source light incident on the liquid crystal is modulated to produce image light.

(Planar structure)
FIG. 3 is an explanatory diagram of a planar structure of the liquid crystal device. In the liquid crystal device of the present embodiment, a rectangular pixel electrode 9 made of a transparent conductive material such as indium tin oxide (hereinafter referred to as ITO) on the TFT array substrate (the outline is indicated by a broken line 9a). Are arranged in a matrix. A data line 6 a, a scanning line 3 a, and a capacitor line 3 b are provided along the vertical and horizontal boundaries of the pixel electrode 9. In the present embodiment, the rectangular area in which each pixel electrode 9 is formed is a dot, and the display can be performed for each dot arranged in a matrix.

  The TFT element 30 is formed around a semiconductor layer 1a made of a polysilicon film or the like. A data line 6 a is connected to a source region (described later) of the semiconductor layer 1 a through a contact hole 5. Further, a pixel electrode 9 is connected to a drain region (described later) of the semiconductor layer 1 a through a contact hole 8. On the other hand, a channel region 1a 'is formed in a portion of the semiconductor layer 1a facing the scanning line 3a.

(Cross-section structure)
FIG. 4 is an explanatory diagram of a cross-sectional structure of the liquid crystal device, and is a cross-sectional side view taken along the line AA ′ in FIG. 3. As shown in FIG. 4, the liquid crystal device 60 of the present embodiment is mainly composed of a TFT array substrate 10, a counter substrate 20 disposed to face the TFT array substrate 10, and a liquid crystal layer 50 sandwiched therebetween. Yes. The TFT array substrate 10 is mainly composed of a substrate body 10A made of a translucent material such as glass or quartz, a TFT element 30, a pixel electrode 9, an alignment film 16 and the like formed inside thereof. One counter substrate 20 is mainly composed of a substrate body 20A made of a light-transmitting material such as glass or quartz, and a common electrode 21 and an alignment film 22 formed inside thereof.

  On the surface of the TFT array substrate 10, a first light shielding film 11a and a first interlayer insulating film 12, which will be described later, are formed. A semiconductor layer 1a is formed on the surface of the first interlayer insulating film 12, and a TFT element 30 is formed around the semiconductor layer 1a. A channel region 1a 'is formed in a portion of the semiconductor layer 1a facing the scanning line 3a, and a source region and a drain region are formed on both sides thereof. Since the TFT element 30 employs an LDD (Lightly Doped Drain) structure, a high concentration region having a relatively high impurity concentration and a low concentration region (LDD region) having a relatively low impurity concentration in the source region and the drain region, respectively. And are formed. That is, a low concentration source region 1b and a high concentration source region 1d are formed in the source region, and a low concentration drain region 1c and a high concentration drain region 1e are formed in the drain region.

  A gate insulating film 2 is formed on the surface of the semiconductor layer 1a. A scanning line 3a is formed on the surface of the gate insulating film 2, and a portion facing the channel region 1a 'constitutes a gate electrode. A second interlayer insulating film 4 is formed on the surfaces of the gate insulating film 2 and the scanning line 3a. A data line 6a is formed on the surface of the second interlayer insulating film 4, and the data line 6a is connected to the high-concentration source region 1d through a contact hole 5 formed in the second interlayer insulating film 4. . Further, a third interlayer insulating film 7 is formed on the surfaces of the second interlayer insulating film 4 and the data line 6a. A pixel electrode 9 is formed on the surface of the third interlayer insulating film 7, and the pixel electrode 9 is a high-concentration drain through a contact hole 8 formed in the second interlayer insulating film 4 and the third interlayer insulating film 7. It is connected to the area 1e. Furthermore, an inorganic alignment film 16 is formed so as to cover the pixel electrode 9 so that the alignment of liquid crystal molecules when a non-selection voltage is applied can be regulated.

In the present embodiment, the first storage capacitor electrode 1f is formed by extending the semiconductor layer 1a. Further, the gate insulating film 2 is extended to form a dielectric film, and the capacitor line 3b is disposed on the surface thereof to form a second storage capacitor electrode. Thus, the above-described storage capacitor 17 is configured.
A first light shielding film 11 a is formed on the surface of the substrate body 10 </ b> A corresponding to the formation region of the TFT element 30. The first light shielding film 11a prevents light incident on the liquid crystal device from entering the channel region 1a ′, the low concentration source region 1b, and the low concentration drain region 1c of the semiconductor layer 1a.

  On the other hand, a second light shielding film 23 is formed on the surface of the substrate body 20A in the counter substrate 20. The second light shielding film 23 prevents light incident on the liquid crystal device from entering the channel region 1a ′, the low concentration source region 1b, the low concentration drain region 1c, and the like of the semiconductor layer 1a. It is provided in a region overlapping with the layer 1a. A common electrode 21 made of a conductor such as ITO is formed on the surface of the counter substrate 20 over substantially the entire surface. Further, an inorganic alignment film 22 is formed on the surface of the common electrode 21 so that the alignment of liquid crystal molecules when a non-selection voltage is applied can be regulated.

  A liquid crystal layer 50 made of nematic liquid crystal or the like is sandwiched between the TFT array substrate 10 and the counter substrate 20. The nematic liquid crystal molecules have a positive dielectric anisotropy, and are horizontally aligned along the substrate when a non-selection voltage is applied, and vertically aligned along the electric field direction when a selection voltage is applied. The nematic liquid crystal molecules have positive refractive index anisotropy, and the product (retardation) Δnd of the birefringence and the liquid crystal layer thickness is, for example, about 0.40 μm (60 ° C.). Note that the alignment regulation direction by the alignment film 16 of the TFT array substrate 10 and the alignment regulation direction by the alignment film 22 of the counter substrate 20 are set to be twisted by about 90 °. Thereby, the liquid crystal device 60 of the present embodiment operates in the twisted nematic mode.

  Further, polarizing plates 18 and 28 made of a material obtained by doping polyvinyl alcohol (PVA) with iodine or the like are disposed outside the substrates 10 and 20. The polarizing plates 18 and 28 are preferably mounted on a support substrate made of a high thermal conductivity material such as sapphire glass or quartz, and are separated from the liquid crystal device 60. Each of the polarizing plates 18 and 28 has a function of absorbing linearly polarized light in the absorption axis direction and transmitting linearly polarized light in the transmission axis direction. The polarizing plate 18 on the TFT array substrate 10 side is arranged so that its transmission axis substantially coincides with the alignment regulating direction of the alignment film 16. The polarizing plate 28 on the counter substrate 20 side has its transmission axis aligned with the alignment film 22. It arrange | positions so that it may correspond with a regulation direction substantially.

The liquid crystal device 60 is disposed with the counter substrate 20 facing the light source. Of the light source light, only linearly polarized light that matches the transmission axis of the polarizing plate 28 passes through the polarizing plate 28 and enters the liquid crystal device 60.
In the liquid crystal device 60 when the non-selection voltage is applied, the liquid crystal molecules horizontally aligned with respect to the substrate are stacked and arranged in a spiral shape by twisting about 90 ° in the thickness direction of the liquid crystal layer 50. Therefore, the linearly polarized light incident on the liquid crystal device 60 is rotated about 90 ° and emitted from the liquid crystal device 60. Since this linearly polarized light coincides with the transmission axis of the polarizing plate 18, it passes through the polarizing plate 18. Accordingly, white display is performed in the liquid crystal device 60 when the non-selection voltage is applied (normally white mode).

  Further, in the liquid crystal device 60 when the selection voltage is applied, the liquid crystal molecules are vertically aligned with respect to the substrate. Therefore, the linearly polarized light incident on the liquid crystal device 60 is emitted from the liquid crystal device 60 without being rotated. Since this linearly polarized light is orthogonal to the transmission axis of the polarizing plate 18, it does not pass through the polarizing plate 18. Accordingly, black display is performed in the liquid crystal device 60 when the selection voltage is applied.

(Inorganic alignment film)
As described above, the inorganic alignment films 16 and 22 are formed inside both the substrates 10 and 20. Although the inorganic alignment film 16 of the TFT array substrate 10 will be described below, the inorganic alignment film 22 of the counter substrate 20 has the same configuration.
The inorganic alignment film 16 has a thickness of 0.02 to 0.3 μm (preferably, 0.002 μm) by silicon oxide such as SiO ₂ or SiO, or metal oxide such as Al ₂ O ₃ , ZnO, MgO, or ITO. 02 to 0.08 μm). For the production of the inorganic alignment film 16, sputtering methods such as ion beam sputtering and magnetron sputtering, vapor deposition, sol-gel method, self-organization, and the like can be used. Below, the manufacturing method of the inorganic alignment film 16 by the ion beam sputtering method is demonstrated.

  FIG. 5A is a schematic diagram of an ion beam sputtering apparatus. The ion beam sputtering apparatus S100 includes a vacuum chamber S3 and an exhaust pump S4 that controls the internal pressure thereof, a substrate holder S5 that fixes the substrate 10 in the vacuum chamber S3, and a target that emits sputtered particles toward the substrate. S2 and an ion source S1 that irradiates an ion beam toward the target. A gas supply source S13 is connected to the ion source S1, and a filament S11 and an extraction electrode S12 are provided inside the ion source S1.

Formation of the inorganic alignment film using this ion beam sputtering apparatus is performed according to the following procedure. First, the substrate 10 is fixed to the substrate holder S5 in the vacuum chamber S3, and the inside of the vacuum chamber S3 is decompressed by the exhaust pump S4. Next, a rare gas such as argon gas is supplied from the gas supply source S13 into the ion source S1, and a voltage is applied to the filament S11 to generate thermoelectrons.
Then, the generated thermoelectrons collide with the introduced rare gas and plasma is generated in the ion source S1. Next, an ion acceleration voltage is applied to the extraction electrode S12 to accelerate ions generated by the plasma. Thereby, an ion beam is irradiated from the ion source S1. The target S <b> 2 irradiated with the ion beam emits sputtered particles made of the inorganic alignment film forming material toward the substrate 10. The sputtered particles are deposited on the substrate 10 to form an inorganic alignment film on the substrate 10.

The pressure in the vacuum chamber S3, may preferably be 5 × ¹⁰ -1 Pa or less and more preferably 5 × ¹⁰ -2 Pa or less. This is because, when this pressure is too high, the straightness of the irradiated sputtered particles decreases. The temperature of the substrate 10 is preferably 150 ° C. or lower, more preferably 100 ° C. or lower, and further preferably 50 to 80 ° C. Thus, by holding the substrate 10 at a relatively low temperature, it is possible to suppress a phenomenon (migration) in which the sputtered particles attached to the substrate 10 move from the position where they are first attached. Furthermore, the ion acceleration voltage applied to the extraction electrode S12 is preferably 400 to 3000V, and more preferably 800 to 2000V. This is because if the ion acceleration voltage is too low, the sputtering rate decreases, and if the ion acceleration voltage is too high, a uniform film cannot be formed.

  FIG. 5B is a side sectional view of the substrate on which the inorganic alignment film is formed. When sputtered particles are continuously incident on the substrate 10 at a substantially constant incident angle, the sputtered particles are deposited in an oblique columnar shape to form a columnar structure 16a made of an inorganic material. Innumerable columnar structures 16 a are formed on the surface of the substrate 10 to form the inorganic alignment film 16. The columnar structure shown in FIG. 5B is obtained by adjusting the angle between the target S2 and the substrate 10 shown in FIG. 5A and causing the sputtered particles to enter the substrate 10 at a predetermined incident angle. A predetermined inclination angle can be given to 16a. In the liquid crystal device, since the liquid crystal molecules are aligned along the columnar structures 16a, the inorganic alignment film 16 can regulate the alignment of the liquid crystal molecules when a non-selection voltage is applied in a predetermined direction. In addition, pretilt can be imparted to the liquid crystal molecules.

  A plurality of inclined surfaces are formed in advance on the surface of the base film of the inorganic alignment film, the inorganic alignment film is formed on the surface by the sputtering method, and the shape of the plurality of inclined surfaces is on the surface of the inorganic alignment film. It is good also as the structure currently transmitted. Further, after forming the inorganic alignment film by the sputtering method, ion milling in which an ion beam is incident at a predetermined angle may be performed to form a concave portion having a predetermined direction on the surface of the inorganic alignment film. Also, ion milling is performed in advance on the surface of the inorganic alignment film, and then the inorganic alignment film is formed by the above sputtering method, and then ion milling is performed again on the surface to form a recess on the surface of the inorganic alignment film. May be. In any case, it is possible to provide an inorganic alignment film that can reliably give a desired pretilt angle to liquid crystal molecules.

(Seal structure)
FIG. 6 is an explanatory diagram of the seal structure according to the first embodiment as described above, and is a side cross-sectional view taken along the line BB of FIG. As shown in FIG. 1, a sealing material 19 is disposed at the peripheral edge of the TFT array substrate 10, and a liquid crystal layer is sealed at the center.

  As shown in FIG. 6, a protrusion 81 is formed on the surface of the substrate body 10 </ b> A of the TFT array substrate 10 in the sealing region where the sealing material 19 is disposed. The protrusion 81 is made of a photosensitive resin material or the like, and is formed using photolithography. The protrusion 81 is continuously formed in an annular shape over the entire circumference of the seal region, and a cross section perpendicular to the continuous direction is rectangular. On the surface of the ridge 81, the inorganic alignment film 16 is disposed with a substantially constant thickness. As a result, the inorganic alignment film 16 is projected to have a height of several μm reflecting the shape of the ridge 81. A portion 82 is formed.

  In the seal region, a groove 91 is formed on the surface of the substrate body 20A of the counter substrate 20. The groove 91 is continuously formed in an annular shape over the entire circumference of the seal region, and a cross section perpendicular to the continuous direction is rectangular. On the surface of the groove 91, the inorganic alignment film 22 is disposed with a substantially constant thickness, whereby the surface of the inorganic alignment film 22 reflects the shape of the groove 91 and has a depth of several μm. 92 is formed. Note that the width of the concave portion 92 is wider than the width of the convex portion 82.

Here, the height of the convex portion 82 is sufficiently long (high) with respect to the depth of the concave portion 92, and the difference is the cell between the inorganic alignment films 16 and 22 that becomes the thickness of the liquid crystal layer 50. It is almost equal to the gap. Specifically, the sum of the difference between the height of the convex portion 82 and the depth of the concave portion 92 and the thickness of the sealing material 19 that enters between the convex portion 82 and the concave portion 92 is configured to be equal to the cell gap. Under such a configuration, the liquid crystal device 60 according to the present embodiment fits the convex portions 82 and the concave portions 92 via the sealing material 19, so that the substrate (between the inorganic alignment films 16 and 22) is connected. A desired cell gap can be defined. Therefore, the liquid crystal device 60 does not require a gap material.
Further, the horizontal alignment between the TFT array substrate 10 and the counter substrate 20 can be ensured by bringing the side surface of the convex portion 82 into contact with the side surface of the concave portion 92.

  Here, the sealing material 19 has a high film density, sufficiently low moisture permeability, and excellent adhesion to the base, and as described above, extremely low moisture permeability and high adhesion organic / inorganic hybrid. Made of polymer. Therefore, according to the liquid crystal device 60 of the present embodiment, moisture absorption and water intrusion are remarkably prevented as compared with the prior art, thereby preventing quality deterioration due to moisture absorption and water intrusion.

In addition, since Zr alkoxide and Al alkoxide are used as the metal alkoxide for the sol-gel solution forming the sealing material 19, these metal alkoxides are hydrolyzed and the metal (Zr, Al) is, for example, [ZrO ₆ ] or [AlO ₆ ], which is an oxide that forms an octahedral structure, such as when bonded to a structure made of an organic functional device or a silane coupling material at the application site, the film density of the moisture-proof film 90 obtained in particular. Becomes higher, moisture permeability becomes lower and moisture resistance becomes higher. That is, if only the silane coupling agent, which is hydrolysed becomes tetrahedral structure as [SiO _4], which is the only bind to the organic functional device, etc. of the coating portion. However, a film having two types of structures including the octahedron structure as described above has a higher film density and a lower moisture permeability than a film having one type of structure. The nature becomes higher. In addition, even in the state of the sol-gel solution before curing, the viscosity of the liquid becomes high and the adhesiveness becomes high by increasing the density of the liquid, thereby improving the adhesion to the application site.

Further, since the metal (Zr, Al) in the metal alkoxide is present in the sealing material 19, an antistatic function is exhibited by releasing charges accumulated in the alignment films 16, 22 and the like. .
If a polar compound such as N-trimethoxysilylpropyl-N, N, N-trimethylammonium chloride is used as the silane coupling material, for example, this has a function of releasing charges accumulated in the alignment films 16, 22 and the like. As a result, the sealing material 19 exhibits an antistatic function.

  In addition, as a silane coupling material for forming a sol-gel solution, an alkoxysilane having an alkoxy group (alkyl group) having a large number of straight-chain carbons and a long straight chain, and a straight chain having a small number of straight-chain carbons. If an alkoxysilane having an alkoxy group (alkyl group) having a short chain is mixed and used, the short chain enters the network structure of the long chain, so that the film density of the sealing material 19 becomes higher. Moisture permeability becomes lower and moisture resistance becomes higher.

  Moreover, since the sealing material 19 has water repellency, and thus prevents moisture from adhering to the sealing material 19, it is possible to prevent moisture from adhering to the sealing material 19, As a result, moisture permeation can be prevented from easily occurring due to adhesion of moisture. In addition, it is possible to prevent moisture from entering the liquid crystal cell 100 due to moisture adhesion.

  Further, according to the liquid crystal cell 100, it is possible to omit the water repellent treatment on the surfaces of the alignment films 16 and 22, and the influence on the liquid crystal element caused by forming the water repellent film on the surfaces of the alignment films 16 and 22 is eliminated. (For example, pretilt disturbance due to non-uniformity of the water repellent film, generation of bubbles in the liquid crystal layer 50 due to contact with the water repellent film, etc.) can be avoided.

Moreover, since the sealing material is formed in a state in which the space between the concave portion and the convex portion is filled, the sealing material has an inner surface side from the outer surface side as compared with the case where there is no concave portion and convex portion as in the prior art. Therefore, the possibility of moisture and the like entering the liquid crystal layer through the sealing material or the interface between the sealing material and the base is reduced.
Furthermore, if the height of the convex portion is sufficiently long with respect to the depth of the concave portion and the difference is made substantially equal to the cell gap, the cell gap can be defined by the fitting of the concave portion and the convex portion. This can eliminate the need for a gap material.

  Further, since the recess 91 is formed in the inorganic alignment film 22 by forming the groove 91 in the substrate body 20A and reflecting the concave shape of the groove 91, the recess 92 is easily formed on the surface of the inorganic alignment film 22. In addition, even when the inorganic alignment film 22 is thin, since the concave portion is not directly formed on the inorganic alignment film 22, it is possible to prevent a defective portion from being generated in the film by forming the concave portion directly. Can do. However, without being limited to this configuration, the substrate main bodies 10A and 20A may be flat and the convex portions or the concave portions may be directly formed on the inorganic alignment films 16 and 22. Further, protrusions (protrusions) or grooves (recesses) may be formed on both the substrate bodies 10A and 20A and the inorganic alignment films 16 and 22, and a large protrusion or recess may be formed by adding them together. .

  In addition, since the inorganic alignment film 16 in the present embodiment is porous due to the columnar structure 16a as shown in FIG. 5B, there is a gap between the sealing material 19 and the substrate 10. In particular, there is a possibility that a relatively large gap may be formed at the interface between the sealing material 19 and the inorganic alignment film 16. Then, moisture, impurities, etc. may enter the liquid crystal layer 50 from the outside of the liquid crystal device 60 through these gaps. When moisture, impurities, etc. enter the liquid crystal layer 50, various functions of the liquid crystal device 60 are hindered. In particular, when water, which is a polarizable molecule, enters the liquid crystal having a polarization structure, alignment failure of the liquid crystal occurs. Will do.

  However, in the liquid crystal device 60 of this embodiment, the convex portions 82 and the concave portions 92 are formed on the surfaces of the inorganic alignment films 16 and 22, and the sealing material 19 is formed in a state where the gaps between the concave portions 92 and the convex portions 82 are filled. Therefore, the width of the sealing material 19 from the outer surface side to the inner surface side becomes longer than in the conventional case where there are no concave portion and convex portion. Therefore, since the length of the intrusion path of moisture and the like becomes longer, moisture and the like enter the liquid crystal layer 50 through the seal material 19 or the interface between the seal material 19 and the alignment films 16 and 22 which are the underlying layers. It can prevent more reliably. Therefore, various functions of the liquid crystal device 60 can be maintained. Therefore, as will be described later, when the liquid crystal device 60 is employed as the light modulation means of the liquid crystal projector, the reliability of the liquid crystal projector can be improved.

(Modification)
FIG. 7 is an explanatory diagram of a modification of the first embodiment. The convex portion 82 and the concave portion 92 of the first embodiment shown in FIG. 6 are formed continuously over the entire circumference of the seal region, and the cross section perpendicular to the continuous direction is rectangular. On the other hand, the convex portion 82a and the concave portion 92a of the first modification shown in FIG. 7A are the same as the first embodiment in that they are continuously formed over the entire circumference of the seal region. The difference is that the cross section perpendicular to the direction is semicircular. Moreover, the convex part 82b of the 2nd modification shown in FIG.7 (b) and the recessed part 92b are different by the point by which the cross section perpendicular | vertical to a continuous direction is made into a triangular shape. Moreover, the convex part 82c and the concave part 92c of the third modified example shown in FIG. 7C are the same as those of the second modified example in that the cross section perpendicular to the continuous direction is a triangular shape. Are different in that they are substantially perpendicular to the substrate.

  In order to form the convex portion of each modification, first, a photosensitive resin layer such as acrylic is formed on the substrate surface. Next, the photosensitive resin layer is exposed using a gray mask (halftone mask) on which a pattern is drawn by a continuous change in shading. As a result, exposure with different depth of focus is performed according to the shade of the gray mask. Thereafter, by developing the photosensitive resin layer, a protrusion having a hemispherical shape or a triangular shape in cross section can be formed. In order to form the recesses of the respective modifications, first, a resist layer is formed on the substrate surface. Next, a desired groove shape is formed in the resist layer by performing photolithography using a gray mask. Then, by etching the substrate using the resist layer as a mask, a groove having a hemispherical shape or a triangular shape can be formed.

Also in each modification mentioned above, the recessed part and the convex part are formed in the surface of an inorganic alignment film similarly to 1st Embodiment, and the sealing material 19 based on this invention is arrange | positioned between these recessed parts and a convex part. With this configuration, the width of the interface between the sealing material 19 and the inorganic alignment film becomes longer than in the case where there are no convex portions and concave portions. Therefore, it is possible to prevent moisture and the like from entering the liquid crystal layer through the gap at the interface, thereby maintaining the function of the liquid crystal device.
Further, since the sealing material 19 is made of an organic / inorganic hybrid polymer having extremely low moisture permeability and high adhesion as described above, moisture absorption and water ingress are significantly prevented as compared with conventional ones. The quality deterioration due to the intrusion of water is prevented.
Therefore, when this liquid crystal device 60 is employed as the light modulation means of the liquid crystal projector, the reliability of the liquid crystal projector can be improved.

(Second Embodiment)
Next, a second embodiment of the liquid crystal device of the present invention will be described with reference to FIG.
FIG. 8 is an explanatory diagram of the seal structure according to the second embodiment, and is a side sectional view of a portion corresponding to the line BB in FIG. 1. In the seal structure of the second embodiment shown in FIG. 8, recesses 182 and 192 are formed on the surfaces of the inorganic alignment films 16 and 22 of both substrates 10 and 20, and the surfaces of the recesses 182 and 192 are made of the sol-gel solution. Although it is common to the first embodiment in that the sealing material 19 is provided, it is different from the first embodiment in that the recesses 182 and 192 of both substrates are not fitted. Note that detailed description of portions having the same configuration as in the first embodiment is omitted.

  As shown in FIG. 8, a plurality (two in FIG. 8) of grooves 181 are formed in an annular shape on the surface of the substrate body 10A of the TFT array substrate 10 in the sealing region where the sealing material 19 is disposed. The inorganic alignment film 16 is formed with a plurality of recesses 191 in an annular shape, reflecting the recess shape of the groove 181 of the substrate body 10A serving as the base. Similarly, a plurality of (two in FIG. 8) grooves 191 are formed on the surface of the substrate body 20A of the counter substrate 20 in a ring shape, and the grooves of the substrate body 20A serving as the foundation are formed on the inorganic alignment film 22. Reflecting the concave shape of 191, a plurality of concave portions 192 are formed in an annular shape.

  The sealing material 19 is filled inside the recesses 182 and 192 of the substrates 10 and 20, and the sealing material 19 is also disposed between the substrates 10 and 20, so that the relative positions of the substrates are fixed. Yes. A desired liquid crystal layer thickness (cell gap) is ensured by interposing a spacer (gap material) 19a mixed in the sealing material 19 between both substrates.

As described above, in the liquid crystal device according to the second embodiment, as in the first embodiment, the concave portions 182 and 192 are formed on the surfaces of the inorganic alignment films 16 and 22, and the concave portions 182 and 192 are formed on the surfaces. Since the sealing material 19 is arranged, the width of the interface between the sealing material 19 and the inorganic alignment films 16 and 22 becomes long even if the concave portions 182 and 192 of both substrates are not fitted. Therefore, moisture or the like can be prevented from entering the liquid crystal layer 50 through the gaps at the interface, and various functions of the liquid crystal device 160 can be maintained.
Further, since the sealing material 19 is made of an organic / inorganic hybrid polymer having extremely low moisture permeability and high adhesion as described above, moisture absorption and water ingress are significantly prevented as compared with conventional ones. The quality deterioration due to the intrusion of water is prevented.
Therefore, when this liquid crystal device 60 is employed as the light modulation means of the liquid crystal projector, the reliability of the liquid crystal projector can be improved.

In the second embodiment, the concave portions 182 and 192 are formed on both the substrates 10 and 20, but convex portions may be formed on one or both substrates. In this case, a desired liquid crystal layer thickness can be ensured by abutting the convex portion against the other side without mixing a spacer in the sealing material.
In addition, as the number of concave portions and convex portions formed on the surfaces of the substrates 10 and 20 increases, the height of the convex portions increases, and the depth of the concave portions increases, the sealing material 19 and the inorganic alignment films 16 and 22 are increased. Therefore, the reliability of the liquid crystal device 160 can be improved.
However, in the liquid crystal device of the present invention, since the sealing material 19 is made of an organic / inorganic hybrid polymer having extremely low moisture permeability and high adhesion, this is simply performed without forming a recess or a protrusion. Even with only the sealing material 19, moisture absorption and water ingress can be significantly prevented as compared with the conventional case.

(projector)
Next, an embodiment of the projector according to the present invention will be described with reference to FIG. FIG. 9 is a schematic configuration diagram showing a main part of the projector. This projector includes the liquid crystal device according to each of the above-described embodiments as light modulation means.

  9, 810 is a light source, 813 and 814 are dichroic mirrors, 815, 816 and 817 are reflection mirrors, 818 is an incident lens, 819 is a relay lens, 820 is an exit lens, and 822, 823 and 824 are liquid crystal devices of the present invention. 825 is a cross dichroic prism, and 826 is a projection lens. The light source 810 includes a lamp 811 such as a metal halide and a reflector 812 that reflects the light of the lamp.

  The dichroic mirror 813 transmits red light contained in white light from the light source 810 and reflects blue light and green light. The transmitted red light is reflected by the reflection mirror 817 and is incident on the light modulation means 822 for red light. The green light reflected by the dichroic mirror 813 is reflected by the dichroic mirror 814 and is incident on the light modulating means 823 for green light. Further, the blue light reflected by the dichroic mirror 813 passes through the dichroic mirror 814. For blue light, in order to prevent light loss due to a long optical path, a light guide means 821 including a relay lens system including an incident lens 818, a relay lens 819, and an exit lens 820 is provided. Blue light is incident on the light modulating means 824 for blue light through the light guiding means 821.

  The three color lights modulated by the respective light modulation means 822, 823, and 824 are incident on the cross dichroic prism 825. The cross dichroic prism 825 is formed by bonding four right-angle prisms. A dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in an X shape at the interface. Yes. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected onto the screen 827 by the projection lens 826 which is a projection optical system, and the image is enlarged and displayed.

The projector described above includes the liquid crystal device according to each of the embodiments described above as light modulation means.
Since the liquid crystal device of each embodiment includes an inorganic alignment film having excellent light resistance and heat resistance, the alignment film is not deteriorated by strong light or heat irradiated from a light source. Further, since the sealing material is made of an organic / inorganic hybrid polymer having extremely low moisture permeability and high adhesion, moisture absorption and water ingress are significantly prevented as compared with the prior art. Furthermore, the possibility of moisture and the like entering the liquid crystal layer through the gap formed at the interface between the sealing material and the inorganic alignment film can be reduced. Accordingly, it is possible to maintain the alignment control function of the liquid crystal molecules in the liquid crystal device, and it is possible to provide a projector having excellent reliability.

  It should be noted that the technical scope of the present invention is not limited to the above-described embodiment, and includes those in which various modifications are made to the above-described embodiment without departing from the gist of the present invention. For example, in the above embodiment, a liquid crystal device including a TFT as a switching element has been described as an example. However, the present invention is applied to a liquid crystal device including a two-terminal element such as a thin film diode as a switching element. It is also possible. In the above embodiment, the transmissive liquid crystal device has been described as an example. However, the present invention can also be applied to a reflective liquid crystal device. In the above embodiment, the liquid crystal device functioning in the TN (Twisted Nematic) mode has been described as an example. However, the present invention can be applied to a liquid crystal device functioning in the VA (Vertical Alignment) mode. Further, in the embodiment, the description has been given by taking a three-plate projection display device (projector) as an example, but the present invention can also be applied to a single-plate projection display device or a direct-view display device.

  The liquid crystal device of the present invention can also be applied to electronic devices other than projectors. A specific example is a mobile phone. This mobile phone includes the liquid crystal device according to each of the above-described embodiments or modifications thereof in a display unit. Other electronic devices include, for example, IC cards, video cameras, personal computers, head-mounted displays, fax machines with display functions, digital camera finders, portable TVs, DSP devices, PDAs, electronic notebooks, and electronic bulletin boards. And advertising announcement displays.

It is a top view of the TFT array substrate of a liquid crystal device. It is an equivalent circuit diagram of a liquid crystal device. It is explanatory drawing of the planar structure of a liquid crystal device. It is explanatory drawing of the cross-section of a liquid crystal device. (A) is a schematic diagram of an ion beam sputtering apparatus, (b) is a side sectional view of a substrate on which an inorganic alignment film is formed. It is explanatory drawing of the seal structure which concerns on 1st Embodiment. It is explanatory drawing of the modification of 1st Embodiment. It is explanatory drawing of the seal structure which concerns on 2nd Embodiment. It is a schematic block diagram which shows the principal part of a projector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Substrate (TFT array substrate), 10A ... Substrate body, 16 ... Inorganic alignment film, 19 ... Sealing material, 20 ... Substrate (opposite substrate), 20A ... Substrate body, 22 ... Inorganic alignment film, 50 ... Liquid crystal layer, 60 ... Liquid crystal device, 81 ... Projection, 82 ... Projection, 91 ... Groove, 92 ... Concave

Claims (10)

A liquid crystal device having a liquid crystal sandwiched between a pair of substrates facing each other,
A sealing material is provided between the inner surfaces of the pair of substrates in a state where the liquid crystal is sealed,
2. The liquid crystal device according to claim 1, wherein the sealing material is formed by placing a sol-gel solution containing a silane coupling material, a metal alkoxide, and water between the substrates and curing the solution.   2. The liquid crystal device according to claim 1, wherein the metal alkoxide comprises at least one of Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide.   3. The liquid crystal device according to claim 1, wherein the silane coupling material includes a plurality of types of alkoxysilanes, and the alkoxysilanes have different numbers of carbon atoms in the respective alkoxy groups.   The sol-gel solution contains a water-repellent material having a water-repellent group, and the sealing material obtained by curing the sol-gel solution has water repellency. 4. The liquid crystal device according to any one of 3.   5. The concave portion is formed on the inner surface side of at least one of the pair of substrates, and the sealing material is formed in a state of filling the concave portion. The liquid crystal device according to one item.   An alignment film is formed on the inner surface side of the one substrate, and the concave portion is formed on the surface of the alignment film reflecting the concave shape formed on the substrate side as a base. The liquid crystal device according to claim 5.   A concave portion is formed on the inner surface side of one of the pair of substrates, a convex portion that fits into the concave portion is formed on the inner surface side of the other substrate of the pair of substrates, and the sealing material is The liquid crystal device according to claim 1, wherein the liquid crystal device is formed in a state in which a space between the concave portion and the convex portion fitted in the concave portion is filled.   An alignment film is formed on each inner surface side of the pair of substrates, and the surface of the alignment film reflects the concave shape or the convex shape formed on the substrate side as a base, and the concave portion or the convex portion is formed. The liquid crystal device according to claim 7, wherein the liquid crystal device is formed. A manufacturing method of a liquid crystal device in which a sealing material is provided between a pair of substrates facing each other, and a liquid crystal layer is sealed with the sealing material,
Applying a sol-gel solution containing a silane coupling material, a metal alkoxide, and water to at least one of the pair of substrates;
Making the pair of substrates face each other through the sol-gel solution;
A method of manufacturing a liquid crystal device, comprising: a step of curing the sol-gel solution to form a sealing material, and bonding the pair of substrates with the sealing material. An electronic apparatus comprising the liquid crystal device according to claim 1.

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