JPH1124089A - Liquid crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent corrosion of a metallic electrode by arranging a protective film, which is provided with a sheet resistance not less than a specific value and with a thickness less than a specific value, in the manner of covering the metallic electrode, and electrically connecting the metallic electrode to a transparent electrode through this protective film. SOLUTION: A liquid crystal device P3 is equipped with a pair of electrode base plates 30 disposed nearly parallelly. These base plates 30 are provided with a substrate 11 whose surface is formed with a number of striped metallic electrodes 12 detachedly from each other. In addition, a protective film 32 is formed nearly on the entire substrate 11 in the manner of covering these metallic electrodes 12, with the surface of this protective film 32 formed with a striped transparent electrode 6 along each metallic electrode. Further, each metallic electrode 12 and transparent electrode 6 are electrically connected by being faced opposite to each other through this protective film 32. This protective film 32 is a sheet resistance of 1.0×10<9> Ω or above, with a thickness of 1,500 Å or below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device having metal electrodes separated from each other.

[0002]

2. Description of the Related Art Hitherto, liquid crystal elements for displaying information using liquid crystals have been used in various fields.

[0003] FIGS. 1 (a) is a diagram showing an example of the structure of a conventional liquid crystal element, the liquid crystal element P ₁ is provided with a pair of glass substrates 1, 1 arranged generally parallel to, These glass substrates 1 and 1 are bonded together by a sealing material 2, and a liquid crystal 3 is held in an internal gap. Also,
On the surface of each of the substrates 1 and 1, a large number of transparent electrodes 6 made of ITO (indium tin oxide) or the like as shown in FIG. 1B are formed. Has an insulating film 7 and an orientation control film 9 formed thereon. Then, by applying a predetermined pulse signal to the transparent electrodes 6, it was supposed to drive the liquid crystal element P _1.

However, since the volume resistance of the transparent electrode 6 is as large as 200 × 10 ^{−8 to} 4000 × 10 ⁻⁸ Ω · cm, the size of the display area is increased, the definition is increased, and the driving speed of the liquid crystal is increased. The delay of the voltage waveform of the pulse signal for driving the liquid crystal has been a problem.

Although it is conceivable to reduce the resistance by increasing the thickness of the transparent electrode 6, it takes time and cost to form the transparent electrode 6, and the adhesion to the glass substrate 1 is deteriorated. Yes, not practical.

As a liquid crystal element that solves such a problem, a liquid crystal element in which a low-resistance metal electrode is provided in addition to a transparent electrode is disclosed in JP-A-2-63019 and JP-A-6-347810.

As shown in FIG. 2A, the liquid crystal element P ₂ has a pair of electrode substrates 10, 10 arranged in parallel, and these electrode substrates 10, 10 are bonded by a sealing material 2. The liquid crystal 3 is held in the internal gap. The electrode substrate 10 includes a transparent glass substrate 11 having a thickness of about 1 mm as shown in detail in FIG. Many are formed so as to be separated from each other. In addition, an insulating layer, specifically, an ultraviolet curable resin (hereinafter, referred to as “UV curable resin”) 13 is disposed between the metal electrodes 12. The UV-curable resin 13 forms a substantially smooth surface together with the metal electrode 12, and a large number of transparent electrodes 6 are formed on the substantially smooth surface.

In the liquid crystal element P ₂ , since the low-resistance metal electrodes 12 are respectively provided so as to be electrically connected to the respective transparent electrodes 6, the delay of the voltage waveform as described above can be reduced.

By the way, aluminum, copper or silver can be considered as a material of the above-mentioned metal electrode 12, and among them, copper is preferable from the viewpoint of low resistance (Applied Physics Vol. 61, No. 11, 1992).

However, copper has a problem of low durability such as being easily oxidized and easily diffused.

As a method for solving such a problem, a method of providing a surface layer of a stable metal on the surface of the metal electrode 12 or a method of forming a SiN film on the surface of the metal electrode 12 (Japanese Patent Laid-Open No. 4-242960) ) Or a method of forming a TiN film (Japanese Patent Laid-Open No. 63-156341).
And a method of forming an Au layer (JP-A-3-60186).

[0012]

However, in these methods, it is necessary to use a special and complicated film formation method such as plating or a photolithography process in order to form a protective film only on the side surface of the wiring or only on the wiring. There was a problem that cost increased.

Accordingly, an object of the present invention is to provide a liquid crystal element capable of preventing corrosion of a metal electrode.

Another object of the present invention is to provide a liquid crystal device which can simplify the manufacturing process and reduce the manufacturing cost.

A further object of the present invention is to provide a liquid crystal device which can solve the problem of so-called voltage waveform delay and can cope with an increase in area and definition.

[0016]

According to the present invention, there is provided a pair of substrates which sandwich a liquid crystal and are arranged so as to face each other, and a plurality of substrates are formed on at least one of the pair of substrates so as to be separated from each other. A liquid crystal device comprising a metal electrode and a plurality of translucent transparent electrodes disposed so as to be electrically connected to the respective metal electrodes. A protective film having a sheet resistance of at least 0.010 ⁹ Ω □ and a thickness of less than 1500 ° is disposed, and the metal electrode and the transparent electrode are electrically connected via the protective film. Provided is a liquid crystal element.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. In addition, the same parts as those shown in FIG.

First, a first embodiment of the present invention will be described with reference to FIGS.

The liquid crystal element P ₃ manufactured in the present embodiment
Has a pair of electrode substrates 30, 30 arranged substantially in parallel, as shown in FIG. These electrode substrates 30,
Numeral 30 is adhered by the sealing material 2, and a large number of spacers 31 are arranged in a gap between the electrode substrates 30, 30 so as to define the gap. In addition, a liquid crystal exhibiting ferroelectricity (hereinafter referred to as “ferroelectric liquid crystal”) and a liquid crystal exhibiting ferroelectricity and antiferroelectricity (hereinafter referred to as “antiferroelectric liquid crystal”) are provided in the gap between the substrates. ) Is sandwiched.

The electrode substrate 30 has a substrate 11 as shown in detail in FIGS. 4A and 4B. On the surface of the substrate 11, striped metal electrodes 12 are separated from each other. Many are formed like this. In addition, these metal electrodes 12
A protective film 32 is formed on substantially the entire surface of the substrate 11 so as to cover the transparent electrodes 6. On the surface of the protective film 32, a stripe-shaped transparent electrode 6 is formed along each metal electrode 12. . Each metal electrode 12 and the transparent electrode 6 are electrically connected to each other by facing each other via the protective film 32. Further, an insulating film (not shown) and an orientation control film 9 are formed so as to cover the transparent electrode 6 and the like. Note that the two electrode substrates 30 are arranged such that the transparent electrodes 6 (metal electrodes 12) have a positional relationship orthogonal to each other.

The protective film 32 is made of a transparent oxide, and is formed so as to cover the surface of each metal electrode 12 and to cover the substrate 11 between the electrodes. Also,
The protective film 32 has a sheet resistance of 1.0 × 10 ⁹ Ω □ or more and a thickness of 1500 ° or less.

The substrate 11 is preferably a light-transmitting substrate that transmits light. Both substrates are polished on both sides and have good parallelism, and may have a thickness of about 0.5 to 2 mm. May be made of glass, quartz, resin, ceramic, or the like.

The metal electrode 12 has a small resistance value,
Any material that can be easily formed into a film with a thickness of about 0.3 to 5 μm and has good adhesion to the light-transmitting substrate 11 may be used, but copper, a copper alloy, silver, or a silver alloy is preferable. .

The transparent electrode 6 is made of a material having excellent translucency, for example, ITO (indium tin oxide; a mixture of indium oxide and tin oxide of about 5 to 10%), indium oxide, tin oxide and the like. preferable.

In FIG. 3, the metal electrode 12 and the protective film 32 are formed on both substrates. However, the present invention is not limited to this, and may be formed on only one substrate.

The orientation control films 9 of both substrates may be made of different materials.

Next, a method of manufacturing the liquid crystal device P ₃ according to the present embodiment will be described with reference to FIG. <Metal electrode forming step> An electrode thin film is formed on the surface of the light-transmitting substrate 11 by a vacuum evaporation method or a sputtering method, and thereafter, patterning is performed by a photolithography method to form a large number of metal electrodes 12 separated from each other. (See FIG. 5A. Hereinafter, the structure in which the metal electrode 12 is formed on the translucent substrate 11 is referred to as “substrate B ₁ with metal electrode”, and the metal electrode 12 is formed on the substrate B ₁ with metal electrode. The side surface is referred to as “electrode surface 15”). <Protective Film Forming Step> Next, the protective film 32 is formed by a general film forming method (see FIG. 3B). Since the protective film 32 may be formed over the entire substrate 11, there is no need to perform patterning by photolithography or the like. <Transparent electrode forming step> Then, an ITO film or the like is formed on substantially the entire substrate 11 by a sputtering method or the like so as to cover the metal electrode 12 formed as described above, and is patterned by a photolithographic etching method. The transparent electrode 6 having the above-described shape is formed (see FIG. 3C).

Thereafter, an insulating film (not shown) and an orientation control film 9 are formed so as to cover the transparent electrodes 6 and the like, and a rubbing process of the orientation control film 9 is performed to form an electrode substrate 30.

Then, a pair of electrode substrates 30, 30 prepared as described above is prepared, a spacer 31 is sprayed on the surface of one of the electrode substrates 30, and a sealing material 2 is applied. to paste together. Then injecting a liquid crystal 3 to substrate gap, creating a liquid crystal element P _3.

Next, effects of the present embodiment will be described.

According to the present embodiment, since the metal electrodes 12 having a small resistance value are electrically connected to the respective transparent electrodes 6 via the protective films 32, the resistance of the voltage waveform is low with low resistance. It is possible to obtain an electrode substrate and a liquid crystal element that can cope with a large area and a high definition without the problem described above.

The surface of each metal electrode 12 is covered with a protective film 32.
Since it is covered by the electrode, corrosion and the like of the electrode can be prevented.

Further, since the protective film 32 is formed on the entire substrate 11 as described above, the patterning step can be omitted. Therefore, the manufacturing process can be simplified and the manufacturing cost can be reduced. The protective film 32
Is formed of a translucent material, so that even if it is arranged in the gap between the metal electrodes, the transmissivity of the liquid crystal element itself is not hindered. Further, since the sheet resistance of the protective film 32 is as high as 1.0 × 10 ⁹ Ω □ or more, adjacent electrodes do not short-circuit through the protective film 32.

The high-resistance protective film 32 and the liquid crystal 3 can be electrically regarded as a series capacitance. Here, if the dielectric constant of the protective film 32 is high to some extent and the film thickness is small, most of the driving voltage is distributed to the liquid crystal layer,
The liquid crystal element can be driven regardless of the presence of such a protective film 32.

The inventor of the present invention has determined the upper limit of the thickness of the protective film 32 so as not to hinder the driving of the liquid crystal element.
An experiment was performed. In the liquid crystal element used in the experiment, the size of one liquid crystal pixel was 100 × 300 μm (the area of the upper surface of the wiring portion for one pixel was 10 × 300 μm), and the cell thickness was 2 μm. As the liquid crystal 3, a chiral smectic liquid crystal having a relative dielectric constant of 5 was used. According to the experimental results, as shown in FIG. 6, when the capacity of the protective film 32 was 0.3 or less (30% or less) of the capacity of the liquid crystal layer, the liquid crystal element was drivable.
Here, the relative dielectric constant of the material used for the protective film 32 is 3 to
Since it is 8, it is understood that the thickness of the protective film 32 is preferably 1500 ° or less, and particularly preferably 1000 ° or less.

On the other hand, the protective film 32 has a sheet resistance of 1.0 ×
It was experimentally determined that a value of 10 ⁹ Ω □ or more (in particular, 1.0 × 10 ¹⁰ or more) was effective. Hereinafter, the contents of the experiment will be described.

In the liquid crystal device used in the experiment, the translucent substrate 11 was a 100 mm × 100 mm glass substrate,
The metal electrode 12 was made of Cu with a thickness of 3000 °, the pitch was 40 μm, and the electrode width was 10 μm. Further, as the protective film 32, an Sb-doped SnO ₂ film is used, and the transparent electrode 6 is used.
In this case, ITO having a thickness of 1000 ° was used. Further, a polyimide film having a thickness of 100 ° is used for the orientation control film 9.
As the liquid crystal 3, a ferroelectric liquid crystal was used. Spacer 3
The particle size of No. 1 was 2 μm. In manufacturing a liquid crystal element having such a structure, the sheet resistance of the protective film 32 is changed by changing the SnO ₂ film forming conditions (specifically, the concentration of Sb in the target), and In a liquid crystal element, disturbance of a display portion due to a leak current between electrodes was examined. FIG. 7 shows the results of the experiment. According to the experiment, the sheet resistance of the protective film 32 was 1.0 × 10 ⁹ Ω.
□ If above, range of drivable voltage (driving margin)
Is sufficiently wide and the contrast does not decrease.

Next, a second embodiment of the present invention will be described with reference to FIGS.

The liquid crystal element P _{4 according} to the present embodiment is the same as that shown in FIG.
As shown in (a) and (b), a pair of electrode substrates 50, 50 arranged substantially in parallel is provided. These electrode substrates 5
Reference numerals 0 and 50 are attached with the sealing material 2 and the spacers 3 are provided in the same manner as the electrode substrates 30 and 30 described above.
1 defines the substrate gap.

The electrode substrate 50 has the substrate 11, and the metal electrodes 12 and the protective film 32 are formed on the surface of the substrate 11, similarly to the electrode substrate 30 described above. The gap between the metal electrodes 12 (more precisely, the protective film 32
An insulating layer 13S for insulating and flattening between the electrodes is disposed in the (concave portion), and the transparent electrode 6 is formed on the surface of the protective film 32 and the insulating layer 13S.

For the formation of the insulating layer 13S, a material which is hardened in response to some external stimulus and has a high fluidity before hardening and a material which transmits light after hardening is used. For example, ultraviolet light (hereinafter referred to as “UV light”)
UV-curable resin (hereinafter referred to as “U”)
V-cured resin), a thermosetting resin that cures when heat is applied, a two-component reaction-curable resin, and the like (hereinafter, the one before being cured is referred to as an “insulating material 13L” The cured product is referred to as “insulating layer 13S”).

Among them, the UV-curable resin is a mixed composition of a monomer, an oligomer and a photoinitiator, and may be of any polymerization type such as an acrylic type, an epoxy type, or an ene / thiol type. (For example, a step of forming a transparent electrode or a step of firing an alignment control film), it is necessary to have heat resistance, chemical resistance, and washing resistance. Therefore, for example, it is preferable to use a reactive oligomer which is a main component, in which a heat-resistant molecular structure is introduced, or a resin in which a crosslinking density is increased by a polyfunctional monomer.

Next, a method of manufacturing the liquid crystal device according to the present embodiment will be described with reference to FIGS.

As in the first embodiment, the metal electrode 12 is formed on the surface of the substrate 11 (see FIG. 9A).
Thereafter, a protective film 32 is formed so as to cover the metal electrode 12 (see FIG. 3B).

In this embodiment, the electrode surface 1
5 may be subjected to an adhesion treatment such as a silane coupling treatment so that the insulating layer 13S formed in a later step adheres well. <Insulating material deposition process> Next, an insulating material 13L, (see FIG. (C)) is applied to the electrode surface 15 of the metal substrate with electrode B _1, to the electrode surface 15 the plate member 16 (hereinafter, " smoothing plate 16 "by superimposing a) to create a laminate B ₂ (FIG see (d). hereinafter, the laminate B _2" the pressing body B
₂ ").

The smooth plate 16 may be a plate-like member having smooth upper and lower surfaces, rich in rigidity, and having a hard surface hardness, and is preferably made of metal, ceramic, glass or the like. In addition, a release agent made of a fluorine-based or silicon-based material is applied to the smooth plate 16 in advance so that the smooth plate 16 can be smoothly separated from the insulating layer 13S (details will be described later). Is also good.

Further, the insulating material 13L may be applied to the smooth plate 16 instead of the electrode surface 15.

[0048] Furthermore, when creating a target pressure body B _2, as the bubbles are not involved in insulating material 13L, the superposition of the smooth plate 16 and the metal electrode with the substrate B ₁ in that performing slowly You need to be careful. In <insulating material filling step> In this step, the target pressure body B ₂ described above will be pressed by the pressing means (see FIG. 10 (a)). Thereby, the smoothing plate 16 is brought into close contact with the protective film 32, and the insulating material 13L is removed from the surface of the protective film 32 and is filled in the gaps between the metal electrodes 12 (recesses of the protective film 32).

As shown in FIG. 10 (a), the pressing means includes a pair of upper and lower plate-like pressing members (hereinafter, referred to as "press plates") 19a and 19b which are configured to be freely contactable and detachable. The pressurized object B is placed between these press plates 19a and 19b.
May be one that performs its pressure by placing ₂ has at least one rotatable pressing roller, the pressure to press the roller as well as presses the pressure body B ₂ by press rollers the surface direction of the pressure body B ₂ may be of a type that is relatively moved.

As the former pressing means, there can be mentioned a means driven by hydraulic pressure, air pressure or water pressure, in addition to a mechanical press machine. The pressure is 1-50 kg / cm ² , especially 5
It is preferably in the range of ２０20 kg / cm ² . <Insulating material curing step> Next, take out the target pressure body B ₂ from the press section, an insulating material curing means curing the insulating material 13L by forming the insulating layer 13S (FIG. (B)
reference).

The type of the insulating material curing means may be selected according to the insulating material to be used. For example, when the insulating material is a thermosetting resin, a heat source is used, and when the insulating material is a UV curing resin, the heat source is used. May use a UV light source. Also, U
In the case where an insulating material that is cured by light other than V light is used, a light source that emits visible light, infrared light, or the like may be used depending on the material. Here, an oven or a hot plate may be used as the heat source, and a high-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, or the like may be used as the UV light source. The insulating material 13L to be cured includes the light transmitting substrate 11 and the smooth plate 1.
6, the heat of the heat source and the light of the light source cause a loss in the translucent substrate 11 and the smooth plate 16. Therefore, the insulating material curing means has a sufficient amount of heat or illuminance in consideration of these losses,
It is preferable that the heat or light surely reaches the insulating material 13L and hardens the insulating material 13L.

By the way, the smooth plate 16 described above, it is necessary to peel from the metal substrate with electrode B ₁ by releasing device (not shown).

The peeling of the smoothing plate 16 may be performed after the insulating material 13L is cured to some extent, and after the smoothing plate 16 is peeled off, heat or light may be applied again to completely cure the insulating material 13L.

According to the present embodiment, the insulating layer 13S is arranged in the gap between the metal electrodes 12 so that the insulating layer 13S and the metal electrode 12 form a substantially flat surface. And the occurrence of crosstalk can be prevented. Further, the same effect as in the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIGS. 11 (a) and 11 (b).

[0056] FIG. 11 (a), is a cross-sectional view showing a structure of a liquid crystal device according to the present embodiment, the liquid crystal element P ₅ is
It has a pair of electrode substrates 50 and 60 arranged substantially in parallel. These electrode substrates 50 and 60 are bonded together with the sealing material 2 as in the case of the above-described electrode substrates 30 and 30, and a substrate gap is defined by the spacer 31. The structure of the lower electrode substrate 50 is the same as that of the above-described second embodiment.

The upper electrode substrate 60 is formed as shown in FIG.
As shown in detail in FIG. 1, a substrate 11 is provided, and a color filter 61 is formed on the surface of the substrate 11. A large number of striped metal electrodes 12 are formed on the surface of the color filter 61 so as to be separated from each other, and a protective film 32 is formed on almost the entire substrate 11 so as to cover these metal electrodes 12. Have been. In addition, in the gap between the metal electrodes 12 (accurately, the concave portion of the protective film 32), an insulating layer 13S for insulating and flattening between the electrodes is provided.
Are arranged, and the transparent electrode 6 is formed on the surface of the protective film 32 and the insulating layer 13S.

The upper electrode substrate 60 and the lower electrode substrate 50 are bonded so that the metal electrodes 12 have a positional relationship orthogonal to each other.

According to the present embodiment, it is possible to obtain a color liquid crystal element having the same effect as in the above-described second embodiment.

[0060]

Embodiments of the present invention will be described below. EXAMPLE 1 In this Example, was prepared a liquid crystal element P ₃ shown in FIG. 100 mm ×
A 100 mm glass substrate was used as the metal electrode 12.
A 100 mm thick NiMo layer, a 2000 mm thick Cu layer,
And a three-layer structure composed of a 200 .mu.m thick NiMo layer was used. The width of the metal electrode 12 was 10 μm, and the pitch was 100 μm. Further, as the protective film 32,
SnO ₂ having a thickness of 500 ° was used, and ITO having a thickness of 1000 ° was used as the transparent electrode 6.

According to this embodiment, a temperature of 80.degree.
A 500-hour endurance test was performed in an environment with a relative humidity of%, but no corrosion was observed on the metal electrode 12.

The inventor conducted an experiment to confirm the effect of this embodiment. That is, there is no protective film 32, and the other structure is the same as that of the above-described electrode substrate.
This electrode substrate was subjected to a 500-hour durability test in an environment at a temperature of 80 ° C. and a humidity of 90%. In this case, corrosion occurred from a part of the side surface of the metal electrode 12. In Example 2 In this example, as the translucent substrate 11, a quartz substrate of 100 mm × 100 mm, the protective film 32, Al ₂ O ₃ was used having a thickness of 800 Å. Other structures and manufacturing methods were the same as those in the first embodiment.

This substrate was placed in an environment of 80 ° C. and 90% humidity,
A 500-hour durability test was performed, but no corrosion was observed on the metal electrode 12. (Embodiment 3) In this embodiment, a plastic substrate of 100 mm × 100 mm was used as the light-transmitting substrate 11, and SiO ₂ having a thickness of 300 ° was used as the protective film 32. The metal electrode 12 has a Cr layer having a thickness of 100 °,
A laminated structure having a 2000-mm-thick Cu layer and a 200-mm-thick Cr layer was used. The metal electrode 12
Has a pitch of 100 μm and an electrode width of 10 μm. Other structures and manufacturing methods were the same as those in the first embodiment.

This substrate was placed in an environment of 80 ° C. and 90% humidity,
A 500-hour durability test was performed, but no corrosion was observed on the metal electrode 12. (Embodiment 4) In this embodiment, the protective film 32
Using ZnO ₂ having a thickness of Å, the metal electrode 12, NiMo layer having a thickness of 200Å, was used consisting of NiMo layer of Ag layer and the thickness 200Å thick 2000 Å. The metal electrode 12 had a pitch of 100 μm and an electrode width of 10 μm. Other structures and manufacturing methods were the same as those in the first embodiment.

This substrate was placed in an environment of 80 ° C. and 90% humidity,
A 500-hour durability test was performed, but no corrosion was observed on the metal electrode 12. In Example 5 This example was prepared as follows crystal element P ₄ shown in FIG.

The metal electrode 12 is made of NiM having a thickness of 100 °.
o layer, 2000 Å thick Cu layer, and 200 Ｎ thick N
A three-layer structure composed of an iMo layer was used.

The protective film 32 has a sheet resistance of 4.
SnO ₂ of 0 × 10 ¹⁰ and a thickness of 600 ° was used, and ITO having a thickness of 1000 ° was used as the transparent electrode 6.

Further, as the insulating material 13L, an acrylic UV curable resin (a UV curable resin composed of 50 parts by weight of pentaerythritol triacrylate, 50 parts by weight of neopentyl glycol diacrylate, and 2 parts by weight of 1-hydroxycyclohexyl phenyl ketone) is used. Composition) was used.

Next, a method for manufacturing the electrode substrate 50 in this embodiment will be described. <Metal electrode forming step> In this step, the transparent substrate 1
On the surface of No. 1, three metal layers (a NiMo layer having a thickness of 100 mm, a Cu layer having a thickness of 2000 mm,
A 200-nm-thick NiMo layer was formed, and the metal layer was patterned by a photolitho-etching method (etching solution; a mixed solution of ferric chloride and ferrous chloride) to form the metal electrode 12 having the above-described shape. . <Protective Film Forming Step> Next, the protective film 32 was formed by RF sputtering. The substrate temperature at this time was 80 ° C., and the sputtering gas was a mixed gas of Ar and O ₂ (flow rate ratio: A
r / O ₂ = 50/50), the pressure was 10 mTorr, and the discharge power was 7.0 × 10 ⁻³ W / cm ² .

Then, the substrate B ₁ with the metal electrode on which the protective film 32 is formed is subjected to UV irradiation ozone treatment for 5 minutes, and thereafter, the surface of the protective film 32 is spin-coated with a coupling agent, and the surface of the A heat treatment was performed for a minute to perform an adhesion treatment. In this embodiment, as the coupling agent,
Silane coupling agent (Nippon Unicar A-17
4) A mixture comprising 1 part by weight and 40 parts by weight of ethyl alcohol was used. <Insulating Material Application Step> In this step, a liquid insulating material 13L was dropped on the surface of the protective film 32 by a dispenser (not shown). The <object pressurizer forming step>, smooth plate 16 to the electrode surface 15 of the metal substrate with electrode B _1, superimposed slowly so as to prevent bubbles caught, I was prepared to be pressure body B _2. <Insulating Material Filling Step> Next, a pair of metal press plates 19
a, using 30 tons hydraulic press machine having a 19b, a press plate 19a to be pressure body B _2, was carried out under pressure is set approximately in the center of 19b. Thereby, the smoothing plate 16 is brought into close contact with the protective film 32, and the insulating material 13 </ b> L is removed from the surface of the protective film 32 and is filled in the gap between the metal electrodes 12. The pressing force was 20 kg / cm ² and the pressing time was 3 minutes. <Insulating material curing step> Next, press 1 to be pressure body B ₂
9 and irradiated with UV light having a center wavelength of 365 nm (light intensity: 200 mJ / cm ² ), thereby obtaining an insulating material 13 L.
Was cured to form an insulating layer 13S.

After the hardening of the insulating material 13L was completed, the smoothing plate 16 was peeled off by a mold release device. <Transparent Electrode Forming Step> Then, an ITO film was formed to a thickness of 700 ° using a DC sputtering method, and was patterned by a photolithographic etching method to form a transparent electrode 6. <Other Steps> Thereafter, an insulating film (not shown) and an orientation control film 9 were formed so as to cover the transparent electrodes 6 and the like, and an electrode substrate 50 was formed.

[0072] Then, bonding a pair of electrode substrates 50 and 50, by injecting a chiral smectic liquid crystal 3 in the gap between the substrates, was prepared a liquid crystal element P _4.

The liquid crystal element P ₄ produced in this embodiment is
Leave it in a 90% humidity environment at a temperature of 0 ° C.
A time durability test was performed, but no corrosion was observed on the metal electrode 12. In Example 6 This example was prepared a liquid crystal element P ₅ shown in FIG. 11.

The transparent substrate 11 has a size of 300 mm ×
A 300 mm double-side polished glass plate was used. As the metal electrode 12, a 100-mm-thick Cr layer,
The lower electrode substrate 50 has a three-layer structure composed of a u layer and a 200-mm thick Cr layer, and the upper electrode substrate 60 has a 100-mm thick Cr layer and a 2000-mm thick Cu layer.
A three-layer structure composed of a layer and a Cr layer having a thickness of 200 ° was used. Further, as the protection film 32, Al ₂ O ₃ having a thickness of 400 ° was used for both the upper and lower substrates. An acrylic UV-curing composed of 50 parts by weight of pentaerythritol triacrylate, 50 parts by weight of neopentyl glycol diacrylate, and 2 parts by weight of 1-hydroxycyclohexyl phenyl ketone is formed on the insulating layers 13S of the upper and lower electrode substrates 50 and 60. A resin composition was used.

Further, the transparent electrode 6 was made of ITO (indium tin oxide) having a thickness of 700 ° on both the upper and lower substrates.

As the orientation control film 9, a polyimide film having a thickness of 50 ° is used for the lower electrode substrate 50, and a SnO ₂ dispersed siloxane film having a thickness of 2000 ° is used for the upper electrode substrate 60. Using. Furthermore, color filter 6
For No. 1, a pigment-based color filter was used. in addition,
An acrylic flattening agent (V259, manufactured by Nippon Steel Corporation) was used as the flattening film 17 of the color filter.

Further, an epoxy-based sealing material was used as the sealing material 2, and the particle size of the spacer 31 was 2.3 μmφ. Further, the liquid crystal 3 has a ferroelectric liquid crystal A of the following chemical formula.
Was used.

[0078]

Embedded image The manufacturing method of the liquid crystal element P ₅ according to this embodiment, except for forming a color filter -61, is identical to the manufacturing method described in the first embodiment described above. However, the alignment control film 9 made of a polyimide film (the lower electrode substrate 50)
Rubbing treatment with a cotton flocking cloth.

When the liquid crystal element P ₅ produced in this example was driven by a signal having a maximum voltage of 20 V, a clear image without crosstalk could be displayed. Further, this liquid crystal element is subjected to 5 ° C. in an environment of 45 ° C. and 90% humidity.
A durability test for 00 hours was performed, but no abnormality was observed.

[0080]

As described above, according to the present invention,
Since the protective film is disposed so as to cover the metal electrode, corrosion of the electrode can be prevented.

Further, according to the present invention, since the metal electrodes having a small resistance value are each capacitively connected to each transparent electrode via the protective film, there is a problem of low resistance and delay of the voltage waveform. Therefore, a liquid crystal element which can cope with a large area and high definition can be obtained.

On the other hand, when an insulating layer is arranged in the gap between the plurality of metal electrodes so that the insulating layer and the metal electrode form a substantially flat surface, the display quality deteriorates,
The occurrence of crosstalk can be prevented.

When a color filter is formed on one of the substrates, a color liquid crystal device having the various effects described above can be obtained.

Further, when the protective film is formed on the entire substrate, the manufacturing process can be simplified by omitting the patterning process, and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of the structure of a conventional liquid crystal element.
(a) is a sectional view, and (b) is a view showing a shape of a transparent electrode.

2A and 2B are diagrams showing another example of the structure of a conventional liquid crystal element, in which FIG. 2A is a cross-sectional view, and FIG. 2B is a detailed cross-sectional view showing the structure of an electrode substrate.

FIG. 3 is a cross-sectional view illustrating a structure of one embodiment of a liquid crystal element of the present invention.

4A and 4B are diagrams illustrating a structure of an electrode substrate used for the liquid crystal element illustrated in FIG. 3, wherein FIG. 4A is a cross-sectional view and FIG.

FIG. 5 is a diagram illustrating a method for manufacturing the liquid crystal element illustrated in FIG.

FIG. 6 is a diagram showing the effect of the present invention.

FIG. 7 is a diagram showing the effect of the present invention.

FIG. 8 is a sectional view showing the structure of another embodiment of the liquid crystal element of the present invention.

FIG. 9 is a diagram illustrating a method for manufacturing the liquid crystal element illustrated in FIG.

FIG. 10 is a diagram illustrating a method for manufacturing the liquid crystal element illustrated in FIG.

FIG. 11 is a cross-sectional view showing the structure of another embodiment of the liquid crystal element of the present invention.

[Explanation of symbols]

Reference Signs List 3 liquid crystal 6 transparent electrode 10 electrode substrate 11 translucent substrate 12 metal electrode 13L insulating material 13S insulating layer 16 smooth plate 30 electrode substrate 32 protective film 50 electrode substrate 60 electrode substrate 61 color filter B ₂ pressed body P ₁ liquid crystal element P ₂ crystal element P ₃ crystal element P ₄ crystal element P ₅ a liquid crystal element

Claims (7)

[Claims] 1. A pair of substrates arranged so as to sandwich a liquid crystal and face each other, a plurality of metal electrodes formed on at least one of the pair of substrates so as to be separated from each other, and one by one. A plurality of translucent transparent electrodes disposed so as to be electrically connected to one of the metal electrodes, wherein at least 1.0 × 10 ⁹ Ω □ is covered so as to cover the metal electrodes. A liquid crystal element, wherein a protective film having a sheet resistance of less than 1500 ° is disposed with a sheet resistance of, and the metal electrode and the transparent electrode are electrically connected via the protective film. 2. The liquid crystal according to claim 1, wherein an insulating layer is disposed in a gap between the plurality of metal electrodes, and the insulating layer and the metal electrodes form a substantially flat surface. element. 3. The liquid crystal device according to claim 1, wherein a color filter is formed on one of the pair of substrates. 4. The protective film has translucency,
The liquid crystal device according to claim 1, wherein the liquid crystal device is formed on substantially the entirety of the substrate. 5. The liquid crystal device according to claim 4, wherein the protective film is an oxide. 6. The liquid crystal device according to claim 5, wherein the metal electrode is formed of copper, a copper alloy, silver, or a silver alloy. 7. The liquid crystal device according to claim 6, wherein the liquid crystal is a liquid crystal exhibiting ferroelectricity or antiferroelectricity.