JPH09274194A - Production of liquid crystal element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a liquid crystal panel which deals with the trend toward higher fineness and larger area and to maintain the uniform orientation of liquid crystals of this liquid crystal panel. SOLUTION: A glass substrate 11 packed with resins 13L between metallic electrodes 12,... is pressurized in an arrow F1 direction via a smoothing plate 32 and the resins 13L are cured in this pressurized state. An elastic film 31b is formed on the surface of this smoothing plate 31 and, therefore, the resin film 32b intrudes between the electrode spacings and forms recesses of a prescribed depth in the films 13L. The similar stage is thereafter repeated by using not the smoothing plate 32 with the elastic film but the smoothing plate which is not coated with the elastic film. As a result, the resins 13L are packed into the recesses and are cured and the smooth surface is formed by the resins 13L and the metallic electrodes 12,.... If the liquid crystal panel is produced by forming transparent electrodes, etc., on this smooth surface, the delay of the voltage waveforms is eliminated by combination use of the metallic electrodes 12,... and the transparent electrodes and the liquid crystal panel dealing the trend toward the higher fineness and the larger area is obtd. In addition, the liquid crystal layer thickness is made uniform and the orientation state of the liquid crystals is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal device, and more particularly, when a thick film drive electrode is formed on the surface of a base substrate, a resin is filled in a gap between the electrodes to form the electrode. And a resin to form a smooth surface.

[0002]

2. Description of the Related Art Conventionally, liquid crystal elements (hereinafter referred to as "liquid crystal panels") have been used in various fields. First, the structure of the liquid crystal panel will be briefly described with reference to FIG.

This liquid crystal panel P ₁ is, as shown in FIG. 1, a pair of electrode substrates 1, 1 arranged so as to face each other.
These electrode substrates 1 and 1 are attached to each other by a sealing material 2, and a ferroelectric liquid crystal 3 is held in the inner space thereof.

On the other hand, each electrode substrate 1 has a glass substrate 5, and ITO transparent electrodes 6, ... Are formed on the surface of the glass substrate 5. These transparent electrodes 6, ...
It has a thickness of about 500 to 5000Å and is usually formed in a stripe shape by a patterning process. Also,
An insulating film 7 for preventing short circuit is formed on the surfaces of these transparent electrodes 6, ...
It is formed to have a thickness of about 00 to 3000 Å, and an alignment control film 9 is formed on the surface thereof with a polyimide resin or the like. Then, such a liquid crystal panel P ₁
Were driven by applying a voltage to the transparent electrodes 6, ..., 6 ,.

However, the transparent electrodes 6, ... Have relatively high resistivity (volume resistance: 200 to 4000 × 1).
^Therefore, the delay of the voltage waveform in the liquid crystal panel has become a problem with the increase in the display area and the higher definition of the liquid crystal panel. As a method of solving such a delay of the voltage waveform, a method of thickening the transparent electrodes 6, ... Is conceivable. According to this method, it takes time and cost to form the film, and the transparent electrode 6 , And the like have a drawback such as poor adhesion to the glass substrate 5 and are not practical.

Therefore, a liquid crystal panel for avoiding the delay of the voltage waveform is disclosed in Japanese Patent Laid-Open No. 2-63019.

As shown in FIG. 2 (a), the liquid crystal panel P ₂ includes a pair of embedded wiring boards 10 arranged in parallel,
10 and these embedded wiring boards 10, 1
The reference numeral 0 is attached by the sealing material 2, and the ferroelectric liquid crystal 3 is held in the internal gap.

The embedded wiring substrate 10 is provided with a transparent glass substrate 11, as shown in detail in FIG.
A large number of stripe-shaped metal electrodes 12, ... Are formed on the surface of the glass substrate 11. These metal electrodes 1
, Are arranged with a predetermined gap therebetween, and the gap is filled with an ultraviolet curable resin (UV curable resin) 13 ,. The resin 13, ... Is the metal electrode 12 ,.
A continuous surface is formed together with each metal electrode 12, ...
Striped transparent electrodes 6, ... Are formed along. Further, the transparent electrodes 6, ... Are covered with the insulating film 7 and the orientation control film 9.

According to the embedded wiring board 10, since the drive signals are applied by the metal electrodes 12, ... And the transparent electrodes 6, .., the resistance values thereof are lowered and the delay of the voltage waveform is eliminated.

Next, a method of manufacturing such a liquid crystal panel P ₂ will be described with reference to FIGS. 3 (a) to 3 (h). (Wiring board forming step) First, a large number of stripe-shaped metal electrodes 12, ... With a film thickness of about 1 μm are formed on the surface of the glass substrate 11 to obtain a wiring board A ₁ as shown in FIG. , The surface of the wiring board A ₁ on the side where the metal electrodes 12, ... Are formed is referred to as “wiring surface 15”). (Resin supplying step) In this step, as shown in FIG. 3 (a), a fixed amount dropping jig 20 such as a dispenser is used, and U
A predetermined amount of a resin monomer liquid 13L such as a V-curable resin is dropped onto the smooth surface of the smooth plate 21 (this resin monomer liquid 1
3L is supplied in a liquid state and then cured, but a liquid resin before being cured is represented by reference numeral 13L, and a resin after curing is represented by reference numeral 13S. "And).

Then, the smooth plate 2 on which the resin 13L is dropped
The wiring surface 15 of the wiring board A ₁ is superposed on the surface of _{No. 1} so that the resin 13L is sandwiched between the smoothing plate 21 and the wiring board A ₁ (see (b) and (c) in the figure.
Which is sandwiched between the smooth plate 21 and the wiring board A ₁ is referred to as “pressurized body A ₂ ”. As a result, the wiring surface 15 of the wiring board A ₁ , that is, the metal electrodes 12, ...
The resin 13L is supplied to the portion where the resin is formed. (Pressure process, resin curing process) In this process, as shown in FIG.
(d) As shown in (e), a press machine 25 is used. The press 25 has upper and lower plates 25U and 25D, and a thick transparent substrate 26 is arranged on the lower surface of the upper plate 25U. Then, the pressed body A ₂ produced in the resin supply step described above is set between the transparent substrate 26 and the lower plate 25D with the wiring substrate A ₁ facing upward, and the press 25 is driven. To do. As a result, the upper plate 25U is driven in the direction of the arrow F ₁ , and the pressed body A ₂ is pressed between the upper plate 25U and the lower plate 25D.

At this time, all the surfaces of the metal electrodes 12, ... Are pressed with a uniform pressure through the smooth plate 21, and the resin 1
3L is excluded from the surface of the metal electrodes 12, ... And is filled in the electrode gap, and forms a smooth surface together with the metal electrodes 12 ,.

While the surfaces of the metal electrodes 12, ... Are pressed as described above, as shown in FIG.
From the side of the transparent substrate 26 to the UV curable resin 13L, ultraviolet rays L
(Hereinafter, referred to as “UV light L”) is irradiated to cure the resin 13L. (Peeling step) Next, the pressure applied by the press 25 is released,
The body A ₂ to be pressed is taken out from the press 25.

Then, with a tool or the like not shown in FIG.
A force is applied in the direction of arrow F ₂ shown in to peel off the smooth plate 21 (see FIG. 6 (h)). (Other steps) After that, the metal electrodes 12, ... And the resin 13
The patterned transparent electrodes 6, ... Are formed on the surface formed by S and the insulating film 7 and the orientation control film 9 are further formed so as to cover the transparent electrodes 6 ,.

Then, the pair of embedded wiring boards 10 and 1
0 is bonded by the sealing material 2, and the ferroelectric liquid crystal 3 is injected into the inner space thereof to form the liquid crystal panel P ₂ .

In the liquid crystal panel P ₂ , since the resin 13S is removed from the surfaces of the metal electrodes 12, ..., The transparent electrodes 6, ... And the metal electrodes 12 ,. Continuity is secured.

[0017]

By the way, the resin 13
Generally has a property of shrinking when being cured by being irradiated with UV light L. Further, according to the conventional manufacturing method, the resin 13L is pressed by the smooth plate 21, It is hardened while forming a smooth surface together with the metal electrodes 12, .... Therefore, as shown in detail in FIG. 4, the cured resin 13 shrinks more than the thickness of the metal electrodes 12, ..., And a recess is formed on the surface of the resin 13 (hereinafter, such resin 13 shrinks. The resulting recessed portion is referred to as "sink") S occurs. Specifically, since the volumetric shrinkage of the resin 13 is about 3 to 10% and the thickness of the metal electrodes 12, ... Is about 1 μm as described above, the depth of the sink mark S is 0.02 to 0.02.
It is about 0.1 μm, which is a value that cannot be ignored. Especially,
When the thickness of the metal electrodes 12, ... Is 2 μm or more, it is impossible to secure the required flatness by the conventional manufacturing method.

Then, such an embedded wiring board 10
When a liquid crystal panel is manufactured by using, there is a problem that the alignment of liquid crystal is not uniform.

Therefore, an object of the present invention is to provide a method for manufacturing a liquid crystal element which eliminates the delay of the voltage waveform and can cope with high definition, while having excellent alignment characteristics.

Further, according to the present invention, the manufacturing quality is kept constant,
An object of the present invention is to provide a method for manufacturing a liquid crystal element, which can improve the manufacturing yield and reduce the cost of the product.

It is another object of the present invention to provide a method of manufacturing a liquid crystal device having excellent display quality without lowering the transmittance of the transparent electrode, causing no optical difference or crosstalk. Is.

[0022]

The present invention has been made in view of the above circumstances, and a wiring board forming step of forming a plurality of drive electrodes on the surface of a base board to form a wiring board, and the drive electrodes. A first resin supplying step of supplying a liquid resin to the portion where the
A first pressurizing step of filling a resin into the gaps between the plurality of drive electrodes based on pressurizing via the pressurizing member of
A method for manufacturing a liquid crystal element, comprising: a first resin curing step of curing the filled resin; and a peeling step of peeling the first pressure member from the wiring board. The member is composed of a smooth plate-shaped member and an elastic elastic film covered with the plate-shaped member, and is depressed in the resin by pressing with the elastic film in the first pressing step. And a second resin supply step of supplying a new liquid resin to the recess of the resin in the first resin curing step to cure the resin in the state of having the recess, and coating with an elastic film. A second pressurizing step of filling resin into the recesses by pressurizing the surface of the drive electrode through a smooth second pressurizing member, and
The second resin curing step of curing the resin supplied in the resin supply step and the peeling step of peeling the second pressure member from the wiring board are sequentially performed after the peeling step. Is characterized by.

In this case, in the first resin curing step,
It is preferable to completely cure the resin filled in the gap between the drive electrodes. Further, the depth of the recess is within a range of 0.2 to 1.0 μm, and the thickness of the resin disposed in the gap between the drive electrodes after the second resin curing step is 1.0 μm. The above is preferable.

On the other hand, the elastic film of the first pressing member may be formed by applying a predetermined solution to the surface of the plate member and heating it. The elastic film of the first pressure member may be formed by adhering a flexible film.

In the first resin supplying step, the resin is dropped onto the first pressure member and the first pressure member onto which the resin is dropped is superposed on the wiring board. A liquid resin may be supplied to the portion where the drive electrodes are formed. Further, in either or both of the first pressurizing step and the second pressurizing step, the structure of the wiring board and the pressurizing member is set between a pair of rams of a press machine. Further, the structure may be pressed by the pair of rams.

On the other hand, the first pressurizing step and the first resin curing step are carried out at the same time, and when the surface of the resin is pressed by the elastic film to form a depression, the resin is applied. It is preferable to cure. Further, the filling is performed while the second pressurizing step and the second resin curing step are simultaneously performed, and the surface of the drive electrode is pressed by the second pressurizing member. The resin may be cured.

The resin is a UV curable resin which is cured by being irradiated with ultraviolet rays, and the resin is irradiated with ultraviolet rays in the first resin curing step and the second resin curing step. Based on the above, the resin may be cured. In this case, in either or both of the first resin curing step and the second resin curing step, a transparent substrate is provided between any one of the pair of rams and the structure. The resin may be interposed and the resin may be irradiated with ultraviolet rays through the transparent substrate while the structure is being pressurized. Further, the resin may be a thermosetting type, and the resin may be cured by heating.

The drive electrode may be a metal electrode. Further, a transparent electrode may be formed on the surface formed by the resin and the driving electrode after the second resin curing step so as to be along the driving electrode.

Based on the above structure, in the wiring board forming step, a large number of drive electrodes are formed on the surface of the base board to form the wiring board. Then, in the first resin supplying step, liquid resin is supplied to the portion where the drive electrode is formed. Further, in the first pressing step, the surface of the drive electrode is pressed via the first pressing member. here,
An elastic film is formed on the surface of the first pressure member,
In the first pressurizing step, the elastic film penetrates into the gap between the drive electrodes to form a recess on the resin surface in the portion which is not in contact with the drive electrode, and the first resin curing step is carried out, whereby the resin is removed. Is cured with a recess having a predetermined depth.

Next, a peeling step is carried out to peel the first pressure member from the wiring board, and a second resin feeding step is carried out to feed a new liquid resin into the recess of the resin. . Further, in the second pressurizing step, the surface of the drive electrode is pressed through the smooth second pressurizing member which is not covered with the elastic film, and the second resin curing step is performed to perform the above-mentioned process. The resin supplied in the second resin supply step is cured.

By the way, in the second resin curing step, the resin already cured in the first resin curing step does not cure and shrink, and is supplied to the recess in the second resin supplying step. Only the resin is cured. Therefore, it is considered that the shallower the depression is, the smaller the shrinkage amount of the resin cured in the second resin curing step is, and the better the flatness between the resin and the drive electrode is. However, in reality, when the recess of the resin is shallower than 0.2 μm, it becomes difficult to uniformly fill the entire substrate with the resin, which rather impairs the flatness. In the present invention, the depth of the recess is controlled by the thickness of the elastic film or the like so that the resin is uniformly filled in the entire substrate, and the shrinkage amount of the resin is reduced so that the flatness between the resin and the drive electrode is reduced. Have secured.

[0032]

Embodiments of the present invention will be described below with reference to the drawings. The same parts as those shown in FIGS. 2 and 3 are denoted by the same reference numerals and description thereof will be omitted.

First, a first embodiment of the present invention will be described with reference to FIGS. Note that the liquid crystal panel (liquid crystal element) manufactured in this embodiment has the same structure as that shown in FIG.
The structure is the same as that shown in (1), and the resin 13 is filled in the gaps between the metal electrodes 12, ....

A method of manufacturing the liquid crystal panel according to this embodiment will be described with reference to FIGS. (Wiring board forming step) First, similarly to the above-mentioned conventional example,
A large number of striped metal electrodes (driving electrodes) 12, ... With a film thickness of about 1 μm are formed on the surface of a glass substrate (base substrate) 11 to obtain a wiring substrate A ₁ (see FIG. 5B). (First Resin Supply Step) In this step, the smooth plate 31 is used as the first pressing member. As shown in detail in FIG. 6, the smooth plate 31 has a smooth plate-shaped member 31a, and the surface of the plate-shaped member 31a is a smooth and elastic film 31b (hereinafter, "elastic film"). 31b ″). Since FIG. 6 is a diagram showing a pressed state, the elastic film 31b is not maintained in a smooth state (details will be described later).

Then, in this step, 13 L of resin monomer liquid is used by using a fixed amount dropping jig 20 such as a dispenser.
Is dropped on the smooth surface of the smooth plate 31 (the surface on the side where the elastic film 31a is formed) by a predetermined amount (as in the conventional example, the liquid resin before curing is represented by reference numeral 13L, and after curing) The resin is represented by reference numeral 13S, and is simply referred to as "resin 13" unless a distinction is required. The resin 13 is a UV curable resin that is cured by irradiation with UV light.

Then, the smooth plate 3 onto which the resin 13L is dropped
The wiring surface 15 of the wiring board A ₁ is superposed on the surface of _{No. 1} so that the resin 13L is sandwiched between the smoothing plate 31 and the wiring board A ₁ (see (b) and (c) in FIG.
A structure constructed by sandwiching 3 L between the smooth plate 31 and the wiring board A ₁ is referred to as “pressurized body A ₂ ”.
As a result, the liquid resin 13L is formed on the wiring surface 15 of the wiring board A ₁ , that is, on the portion where the metal electrodes 12, ... Are formed.
Will be supplied. (First Pressing Step, First Resin Curing Step) In this step, a pressing machine 25 is used as shown in FIGS. This press machine 25 has upper and lower plates (rams) 25U, 25D.
And has a thick transparent substrate 2 on the lower surface of the upper plate 25U.
6 are arranged. Then, the pressed body (structure) A ₂ produced in the resin supply step described above is transferred to the transparent substrate 26.
Then, the wiring board A ₁ is set between the lower plate 25D and the lower plate 25D, and the press 25 is driven. As a result, the upper plate 25U is driven in the direction of the arrow F ₁ , and the pressed body A ₂ is pressed between the upper plate 25U and the lower plate 25D.

The pressing force at this time is set so that the elastic film 31b of the smooth plate 31 is brought into a predetermined deformed state. That is, the pressing force at this time is thinned by being pressed by the metal electrodes 12, ... In the portion where the elastic film 31b of the smooth plate 31 is in contact with the metal electrodes 12 ,. At a portion not in contact with 12, ..., The pressing force is set so as to enter the electrode gap by a predetermined amount while pressing the liquid resin 13L. As a result, the resin 13L is
The metal electrodes 12, ... Are completely removed from the surface and filled in the gaps between the electrodes, and the resin 13 is filled in the gaps.
The surface of L is pressed by the elastic film 31b of the smooth plate 31 and is pushed in by a predetermined amount from the surface of the metal electrodes 12, ....

Then, as shown in FIG. 5 (f), in the state where the surfaces of the metal electrodes 12, ... Are pressurized as described above, that is, in the state where the first pressurizing step is performed. , UV light L is irradiated to the UV curable resin 13L from the side of the transparent substrate 26 to simultaneously perform the first resin curing step, and the resin 13L
To cure.

Here, when the resin is cured, the surface of the resin 13L is 0.02-0.1 μm as the resin shrinks due to curing shrinkage.
Although the sink mark described above occurs phenomenonally (see FIG. 4), in the present embodiment, since the elastic film 31b is cured while being pressed against the surface of the resin 13 as described above, The surface of the resin 13 is further lowered to form a recessed portion 23 having a depth of about 0.2 to 1.0 μm as shown in detail in FIG. The concave portion 23 that is formed as a result is referred to as a “dent 23” in distinction from a sink mark that occurs phenomenologically).

The UV light L is sufficiently irradiated in this step so that the resin 13 is completely cured so that shrinkage does not occur even if UV light is re-irradiated in the subsequent step. (First Peeling Step) Next, the pressure applied by the press machine 25 is released, and the body A ₂ to be pressed is taken out of the press machine 25.

After that, using a tool not shown in FIG.
The smooth plate 31 is peeled off by applying a force in the direction of the arrow F ₂ shown in FIG. As a result, as shown in FIG. 5 (h), the metal electrode 1
Structure A ₄ in which the gap between 2, ...
(Hereinafter, this integrated body is referred to as “intermediate substrate A ₄ ”, and the surface on which the metal electrodes 12, ... Are formed is referred to as “wiring surface 3”.
0 "). (Second resin supply step) Next, a second resin supply step is performed on the intermediate substrate A _{4. In} this step, the elastic film 3 is used.
Instead of the smooth plate 31 covered with 1b, a smooth plate not covered with an elastic film and having a smooth surface (second pressing member)
21 is used (see FIG. 8 (a)).

A fixed amount dropping jig 2 such as a dispenser
0 is used to drop a predetermined amount of a resin monomer liquid 13L such as a UV curable resin on the smooth surface of the smooth plate 21 (as in the conventional example, the liquid resin before curing is represented by reference numeral 13L, The subsequent resin is represented by reference numeral 13S, and is simply referred to as "resin 13" if no distinction is required).

After that, as shown in FIGS. 8 (b) and 8 (c),
The wiring surface 30 of the intermediate substrate A ₄ is superposed on the surface of the smooth plate 21 onto which the resin 13L has been dropped so that the resin 13L is sandwiched between the smooth plate 21 and the intermediate substrate A ₄ (hereinafter, the resin 13L is smooth. What is sandwiched between the plate 21 and the intermediate substrate A ₄ is referred to as “subject A ₅ ”.
As a result, a new liquid resin 13L is supplied to each of the recesses 23, ...

The resin 13L used in this step is made of the same material as that used in the resin supply step described above. (Second pressurizing step, second resin curing step) Then, in this step, as shown in FIGS. 8 (d) and 8 (e), the above-mentioned pressing machine 25 is used again and the transparent substrate 26 and Lower plate 25D
In the meantime, the pressed body (structure) A ₅ is set with the intermediate substrate A ₄ on the upper side, and the press 25 is driven.
As a result, the upper plate 25U is driven in the direction of arrow F ₁ ,
The pressed body A ₅ is pressed between the upper plate 25U and the lower plate 25D.

At this time, the smooth plate 21 is pressed against the surface of the metal electrodes 12, ...
The V-curable resin 13L is completely removed from the surfaces of the metal electrodes 12, ... And is filled in the depressions 23 ,. Further, since the elastic film is not formed on the surface of the smooth plate 21, the resin 13L forms a smooth surface together with the surfaces of the metal electrodes 12, ... (See FIG. 9).

Then, in the state where the surface of the metal electrodes 12, ... Is pressed and the second pressing step is performed as described above, as shown in FIG. From U
The V-curing resin 13L is irradiated with UV light L and the second resin curing step is simultaneously performed to completely cure the resin 13L. (Second Peeling Step) Next, the pressure applied by the press machine 25 is released, and the body A ₅ to be pressed is taken out of the press machine 25.

After that, with a tool or the like not shown in FIG.
A force is applied in the direction of arrow F ₂ shown in FIG. 8 to peel off the smooth plate 21 to obtain a substrate A ₆ as shown in FIG. 8 (h). This board A
_{In 6} , the resin 13 is filled in the gap between the metal electrodes 12, ... And forms a substantially smooth surface together with the metal electrodes 12, ... (See FIG. 9). (Other steps) After that, the resin 13 and the metal electrode 12,
The transparent electrodes 6, ... Are formed in a pattern along the metal electrodes 12, ...
The transparent electrodes 6, ... Are covered with the insulating film 7 and the orientation control film 9 to form the embedded wiring substrate 10. The resin 13
Are excluded from the surface of the metal electrodes 12, ...
The transparent electrodes 6, ... And the metal electrodes 12 ,.

Then, a pair of the embedded wiring substrates 10 and 10 thus produced are bonded to each other, and the liquid crystal 3 is injected into the gap between the substrates to produce a liquid crystal panel.

In the present embodiment, the thickness of the resin 13 arranged in the gap between the metal electrodes 12, ... After the second resin curing step is 1.0 μm or more.

By the way, in this embodiment, the elastic film 3 is used.
1b may be formed by any method as long as the surface is smooth, for example, a predetermined solution is applied to the surface of the plate-shaped member 31a by a coating method such as roll coating, bar coating, or dip coating, It may be formed by heating, or may be formed by adhering a flexible film.

As a material of the elastic film 31b, a polyurethane-based, polyamide-based, polyimide-based, acrylic-based, or epoxy-based material may be used as long as it has some elasticity after curing and can be easily formed into the plate-shaped member 31a. Any material may be used. Furthermore, the elastic film 31b may be of any type such as a one-component type, a mixed type of two or more types, a thermosetting type, or a photo-curing type. However, the formed elastic film 31b is
In a series of liquid crystal panel manufacturing processes, it is necessary that the plate-shaped member 31a and the plate-shaped member 31a are sufficiently adhered so as not to separate from each other. Furthermore, as for the film thickness of the elastic film 31b, the surface of the resin 13L is pushed in a predetermined amount from the surfaces of the metal electrodes 12, ... Any film thickness may be used as long as it forms a recess 23 having a depth of about 0.2 to 1.0 μm (film thickness). Specifically, the thickness of the elastic film 31b is from several μm to several μm. There is a degree of freedom of about 10 μm.

On the other hand, as the material of the plate member 31a of the smooth plate 31, any material may be used as long as it has a high surface hardness and a high rigidity, and metal, ceramics, or glass is used. Further, on the surface of the plate-shaped member 31a,
It is processed by precision cutting, grinding, polishing, or other processing methods, and the flatness per 100 mm length is 10
It is set within μm, preferably within 2 μm.

Further, in the present embodiment, the resin filled in the gaps between the metal electrodes 12, ... Is a mixed composition of a UV-curable resin monomer, an oligomer and a photopolymerization initiator, such as an acrylic type or an epoxy type. , Ene / thiol type, etc. may be used, but heat resistance, chemical resistance, and cleaning resistance should be set so that it can withstand the manufacturing process of liquid crystal panels (for example, ITO sputter film forming process and alignment film baking process). It is necessary to have it. Therefore, for example, a reactive oligomer as a main component into which a heat-resistant molecular structure is introduced or a cross-linking density increased by a multi-functional monomer is preferable. Further, in the above-described embodiment, UV light is irradiated to cure the resin 13L, but needless to say, it is not limited to this, and light that transmits a transparent medium such as the glass substrate 11 and cures the resin 13L may be used. If,
Light of other wavelengths such as visible light and infrared light may be used.
However, when using these visible light and infrared light, it is necessary to appropriately change the material of the resin 13 according to the wavelength of the light used. Furthermore, not only such a photo-curable resin but a thermosetting resin monomer may be used.

On the other hand, the glass substrate 11 may be made of a generally used one for liquid crystal substrates, for example, soda glass (blue plate glass) may be used. In addition, it is preferable that the glass substrate 11 has a thickness of about 1 mm and both surfaces thereof are polished to have good parallelism. Further, the glass substrate 11 transmits UV light as much as possible, and
Any material may be used as long as it has a strength so as not to be broken in each pressurizing step, but quartz glass, BK7 glass and the like are particularly preferable.

Further, the metal electrodes 12, ... Have a small resistance value such as aluminum, chromium, molybdenum, copper,
Moreover, it is preferable that the film can be easily formed into a film having a thickness of about 1 μm and that it has good adhesion to glass. The wiring surface 15 of the wiring board A ₁ may be subjected to a contact treatment such as a silane coupling treatment so that the UV curable resin 13L adheres well.

Further, as the press 25, what is necessary is that it is provided with the upper and lower plates 25U and 25D and has a pressing force that can uniformly spread the resin 13L over the entire wiring board A _1. Any machine such as a hydraulic cylinder, an air cylinder press machine, or a liquid press machine may be used. Moreover, the pressure is 5 to 50 kg.
A range of / cm ² is desirable. Furthermore, in the first pressurizing step and the second pressurizing step, the same type of press machine may be used, or different types of press machines may be used.

Further, the UV lamp for irradiating the UV light may be any UV lamp having an illuminance sufficient to cure the resin 13L, for example, a high pressure mercury lamp, a low pressure mercury lamp,
A xenon lamp or the like may be used.

Next, the operation of the present embodiment will be described.

In the first pressing step, the metal electrode 1
Since the smooth plate 31 is pressed against the surfaces of 2, ..., The liquid resin 13L is completely removed from the surfaces of the metal electrodes 12 ,. In addition, this smooth plate 3
Since 1 has an elastic film 31b on its surface, the elastic film 31b is thinned by being pressed by the metal electrodes 12, ... In a portion in contact with the metal electrodes 12 ,.

Further, in the portion which is not in contact with the metal electrodes 12, ..., The elastic film 31b presses the resin 13L and enters the gap between the metal electrodes 12, ... As shown in FIG.

When the UV light L is irradiated under such a pressure, the resin 13L is cured and shrunk and pressed by the elastic film 31b, resulting in a recess having a depth of about 0.2 to 1.0 μm. 23 is formed (see FIG. 7).

Then, a new liquid resin 13L is supplied to the resin recess 23 (second resin supplying step), and the resin 13L is pressed through the smooth plate 21 not covered with the elastic film. (Second pressurizing step). Therefore, resin 1
3L is excluded from the surfaces of the metal electrodes 12, ... And is filled in the recesses 23 to form a smooth surface together with the metal electrodes 12 ,.

Next, in the second resin curing step, UV is used.
Although the light L is irradiated, the resin (first layer) already cured in the first resin curing step does not cure or shrink, and the resin 13L (newly supplied in the second resin supplying step) 2nd layer)
Only hardened. This newly supplied resin 13L
Shrinks at the same time as it cures, but its amount is small, so the shrinkage amount is small, and therefore the resin 13L is cured in a state in which a substantially smooth surface is formed with the metal electrodes 12 ,.

By the way, the flatness of the resin 13 and the metal electrodes 12, ... Is better as the shrinkage amount of the resin 13 cured in the second resin curing step is smaller. It is considered that the shallower is the better the flatness. However, in reality, the resin depression 23
Is less than 0.2 μm, it becomes difficult to uniformly fill the entire substrate with the resin 13L, which rather impairs the flatness. In the present embodiment, since the resin recess 23 is within the range of 0.2 to 1.0 μm,
The resin 13L can be uniformly filled in the entire substrate, and the shrinkage amount of the resin 13L can be reduced. As a result,
The flatness due to the resin 13 and the metal electrodes 12, ... Can be improved.

Next, the effect of this embodiment will be described.

According to the present embodiment, the resin 13L cured in the second resin curing step is the resin supplied in the second resin supplying step, but this newly supplied resin 13L is used. Has a very small thickness of 1.0 μm or less, the contraction amount thereof is also very small. Moreover, even if the second resin supply step is performed in the state where the sink mark is generated on the surface of the resin 13S as in the conventional case, the sink mark is 0.02 to 0.1 μm.
It is difficult to uniformly fill the entire substrate with the resin 13L because it is shallow, but in the present embodiment, since the resin recess 23 has a depth of 0.2 μm or more, such a problem also occurs. It becomes possible to uniformly fill the entire substrate with the resin 13L. Further, in the second pressurizing step and the second resin curing step, the resin 13L is cured while pressing the surface of the metal electrodes 12, ... With the smooth flat plate 21 not covered with the elastic film. did. In the present embodiment, due to these factors, the surface formed by the resin 13 and the metal electrodes 12, ... After the second resin curing step becomes smooth, and the transparent electrodes 6, 6 are formed on this smooth surface. .. is formed to form a liquid crystal panel, the orientation of the liquid crystal is kept uniform.

In other words, sink marks or the like are not generated on the surface of the resin 13, the alignment of the liquid crystal is not uneven, and the manufacturing quality of the liquid crystal panel can be made constant. As a result, the manufacturing yield is improved and the cost of the product can be reduced.

Further, according to the present embodiment, since the resin 13L is completely cured in the first resin curing step, the resin cured in the second resin curing step is the second resin.
This is the resin 13L newly supplied in the resin supply step of. Therefore, the amount of shrinkage of the resin in the second resin curing step is extremely small, the flatness of the resin 13 is remarkable, and the above-mentioned effect is remarkable.

Further, according to the present embodiment, the first pressurizing step and the first resin curing step are carried out at the same time, and the resin 1
Since the resin 13L is cured while the surface of 3L is pressed by the elastic film 31b, the recess 23
The depth can be accurately controlled to a predetermined amount, and as a result, the above effect can be reliably obtained. Further, the second pressurizing step and the second resin curing step are simultaneously performed, and the filled resin 13L is cured while the surface of the metal electrodes 12, ... Is being pressed through the smooth plate 21. As a result, the surface of the resin 13 can be made smooth, and as a result, the above effects can be reliably obtained.

On the other hand, according to the present embodiment, the resin 13
Is a UV curable resin that is cured by being irradiated with UV light,
In addition, the transparent substrate 26 is disposed in the press 25, and the first resin curing step of irradiating the resin 13L with the UV light L through the transparent substrate 26 and the first pressurizing step are performed at the same time. Therefore, the depth of the recess 23 can be accurately controlled, and the above-described effects can be easily and reliably obtained.

In this embodiment, the resin 13
The transparent electrodes 6, ... Are formed along the metal electrodes 12, ... On the smooth surface formed by the metal electrodes 12 ,.
, And the transparent electrodes 6, ... Can be driven by applying a drive voltage. Therefore, since the metal electrodes 12, ... Have low resistance, the resistance value is reduced as compared with the case where only the transparent electrodes 6, ... Are driven, the delay of the voltage waveform is eliminated, and high-definition liquid crystal panel can be supported. Can be obtained.

Further, since the delay of the voltage waveform is eliminated in this manner, it is not necessary to form the transparent electrodes 6, ... Thick, and the transmittance of the transparent electrodes 6 ,. Nothing. Further, since the metal electrodes 12, ... Are formed on the back side of the transparent electrodes 6 ,.
There is no unevenness in the orientation control film 9, and there is no concern about optical difference or occurrence of crosstalk. Therefore, according to the present embodiment, such a liquid crystal panel having excellent display quality can be manufactured.

Further, conventionally, when the thickness of the metal electrodes 12, ... Is increased to 2 μm or more, it is difficult to secure the flatness of the resin surface due to the large amount of sink marks. However, according to the present embodiment. If so, there is no such problem. Therefore, the thickness of the metal electrodes 12, ... Can be increased, so that the resistance of the liquid crystal panel can be reduced, and a liquid crystal panel that can cope with higher definition can be obtained.

In the present embodiment, the liquid crystal panel is manufactured by repeating the series of steps such as the resin supplying step, the pressurizing step, and the resin curing step twice, but the invention is not limited to this. The liquid crystal panel may be manufactured by repeating three times or more.

[0075]

EXAMPLE First, a first example will be described.

A method of manufacturing the liquid crystal panel according to this embodiment will be described. (Wiring Substrate Forming Step) In this step, the glass substrate 1
As No. 1, soda lime glass having dimensions of 120 × 120 × 1.1 mm and polished on both sides was used.

Then, on the surface of the glass substrate 11,
2μm aluminum (Al) film by sputtering
Film thickness and patterning is performed by photolithographic etching method to form striped metal electrodes 12, ...
Was formed. The metal electrodes 12, ... Have a pitch of 320 μm, a wiring width of 20 μm, and a number of 370.
Book.

The surface of each of these metal electrodes 12, ... Was spin-coated with a coupling agent consisting of 1 part by weight of A-174 (manufactured by Nippon Unicar Co., Ltd.) and 40 parts by weight of ethyl alcohol as a silane coupling agent. , 100 ° C
Resin 1 which is heat-treated at the temperature of 20 minutes and filled in the subsequent process
For No. 3, adhesion improvement treatment was performed. (First Resin Supply Step) In this step, the plate-shaped member 3
A smooth plate 31 having an elastic film 31b formed on the surface of 1a was used.

The plate member 31a has a size of 140 ×
140 × 1.1mm, the flatness is 5μ by double side polishing
A soda-lime glass finished to m or less was used. In addition, the elastic film 3 having a thickness of 10 μm is formed on the surface of the plate member 31a.
1b was formed. In forming the elastic film 31b, first, a liquid elastic film material prepared by mixing a two-component overcoating agent (LC-2040; manufactured by Sanyo Kasei Co., Ltd.) consisting of 100 parts by weight of a main agent and 37 parts by weight of a curing agent is used. Member 31
Spin coating on one side of a and use 8 for temporary curing of the material
Baking was performed at a temperature of 0 ° C. for 10 minutes, and this was repeated twice, and then baking was performed at a temperature of 200 ° C. for 1 hour for main curing.

As the UV curable resin 13, a UV curable resin composition comprising 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 was used. Dispenser 2
0 was dripped almost at the center of the smooth plate 31. In addition,
The amount of the UV curable resin 13L dropped was 250 μl.

Then, the wiring surface 15 of the wiring board A ₁ is slowly superposed on the surface of the smooth plate onto which the resin 13L has been dropped so as not to entrap air bubbles, and left for a while to form the body A ₂ to be pressed. did. (First Pressing Step, First Resin Curing Step) Further, in this embodiment, a 5-ton hydraulic press 25 was used and the sizes of the upper and lower plates 25U and 25D were set to 250 × 250 mm square. Further, the transparent substrate 26 has 120 × 120 × 60
This transparent substrate 26 using a BK7 glass plate with a size of mm
Was used by being accurately adhered to the lower surface of the upper plate 25U with an epoxy adhesive. In addition, 1 is provided on the four sides of the transparent substrate 26.
Four 00W high-pressure mercury lamps were arranged so that UV light could be irradiated.

Then, the body A ₂ to be pressed is set between the transparent substrate 26 and the lower plate 25D, the pressure is increased to 3 tons in about 1 minute, and the pressure is maintained for 10 minutes. The UV light L was irradiated from the four sides of the transparent substrate 26 for 2 minutes from the high pressure mercury lamp to completely cure the resin 13. (First Peeling Step) Next, the pressure applied by the press machine 25 was released, the pressed body A ₂ was taken out of the press machine 25, and the smooth plate 31 was peeled off by a tool (not shown) or the like.

The thickness of the resin 13 was about 1.5 μm. (Second resin supplying step) In this step, a smooth plate 21 without an elastic film is used, and the smooth plate 21 is
150 μl of 13 L of resin was dropped by the dispenser 20.

The resin 13L is the same as that used in the first resin supplying step, and the smooth plate 21 is
The same material and shape as the plate-shaped member 31a used in the first resin supplying step is used without the elastic film.

Then, the wiring surface 30 of the intermediate substrate A ₄ is slowly superposed on the surface of the smooth plate onto which the resin 13L has been dropped so as not to entrap air bubbles, and left in that state for a while. Created ₅ . (Second Pressing Step, Second Resin Curing Step) Then, the pressed body A ₅ is set between the transparent substrate 26 and the lower plate 25D with the intermediate substrate A ₄ on the upper side. The pressure was applied in the same manner as in the step of applying pressure and irradiation with UV light was performed. That is, about 1
The pressure is increased to 3 tons over a period of 10 minutes.
After being held for a minute, UV light L was irradiated from the high pressure mercury lamp for 2 minutes to completely cure the resin 13. (Second peeling step) Thereafter, the pressed body A ₅ is pressed by the press 2
Then, the smooth plate 21 was taken out from the sample No. 5, and a substrate A ₆ was prepared.

According to this example, it was confirmed that the metal electrodes 12, ... And the resins 13, ... Formed smooth surfaces on this substrate A ₆ .

Next, the second embodiment will be described.

In this embodiment, the plate member 31a of the smooth plate 31 has a size of 140 × 140 × 1.1 mm,
A soda-lime glass having a flatness of 5 μm or less finished by double-sided polishing was used. An adhesive was applied to the surface of the plate-shaped member 31a, and a 20 μm-thick polyterephthalate film was pressure-bonded with a roll laminator to obtain an elastic film 31b. Was formed.

The other structure and manufacturing method were the same as those in the first embodiment.

According to this example, it was confirmed that the metal electrodes 12, ... And the resins 13, ... Formed a smooth surface in the embedded substrate.

In this embodiment, the elastic film 31b is used.
Although a polyterephthalate film was used for the above, any material may be used as long as it has elasticity to some extent.
A resin film such as polyethylene, polyester, polyether, or ether ketone may be used, or a rubber film such as polyurethane or silicone may be used.

Next, a third embodiment will be described with reference to FIG.

In this embodiment, as the resin 13, Cemedine 1565 (made by Cemedine Co., Ltd.) and the curing agent D are used.
Using an epoxy thermosetting resin monomer in which and are mixed in a ratio of 10: 1, as a press machine, as shown in FIG.
Heaters 35H, 35H inside the upper and lower plates 35U, 35D
The press machine 35 incorporating the above was used. In addition, in the first and second resin curing steps, heat treatment at 120 ° C. for 30 minutes is performed instead of UV light irradiation, and the resin 13L is cured by this heat treatment.

The other conditions were the same as those in the first embodiment.

When this example was carried out, it was confirmed that the metal electrodes 12, ... And the resins 13, ... Formed smooth surfaces in the embedded substrate.

[0096]

As described above, according to the present invention,
The resin that is cured in the second resin curing step is the resin that was supplied in the second resin supply step, but the amount of newly supplied resin is very small, so the amount of shrinkage is also very small. . Further, even if the second resin supplying step is performed in the state where the sink marks are generated on the surface of the resin as in the conventional case, since the sink marks are shallow, it is difficult to uniformly bury the resin on the entire substrate. However, according to the present invention, the first
In the pressurizing step and the first resin curing step, the resin is cured using the first pressurizing member having the elastic film so as to have a recess, so that the depth of the recess is within a predetermined range. By this, it becomes possible to uniformly fill the entire substrate with the resin. Further, in the second pressing step and the second resin curing step, the resin is cured while the surface of the drive electrode is pressed by the smooth second pressing member which is not covered with the elastic film. I did it. As a result, after the completion of the second resin curing step, the resin filled in the gaps between the drive electrodes forms a smooth surface together with the drive electrodes, and a transparent electrode or the like is formed on this smooth surface. Even if a liquid crystal element is manufactured by using the above method, the alignment of the liquid crystal is kept uniform. In other words, sink marks or the like do not occur on the surface of the resin, and the manufacturing quality of the liquid crystal element can be made constant. As a result, the manufacturing yield is improved and the cost of the product can be reduced.

Such an effect becomes particularly remarkable when the resin is completely cured in the first resin curing step, and the depth of the recess is set within the range of 0.2 to 1.0 μm. Moreover, when the thickness of the resin disposed in the gap between the drive electrodes after the second resin curing step is 1.0 μm or more, it becomes particularly remarkable.

When the first pressurizing step and the first resin curing step are carried out simultaneously and the resin is cured while the surface of the resin is pressed by the elastic film, The dents formed on the surface of the resin can be accurately controlled to a predetermined depth, and as a result, the above-described effects can be reliably obtained. Further, the filled resin is applied in a state in which the second pressurizing step and the second resin curing step are simultaneously performed and the surface of the drive electrode is pressed by the second pressurizing member. When the resin is cured, the surface of the resin can be made smooth, and as a result, the above-mentioned effects can be reliably obtained.

Further, the resin is a UV curable resin which is cured by being irradiated with ultraviolet rays, and a transparent substrate is interposed between any one of the rams and the structure in the press machine to form the transparent substrate. When the resin is irradiated with the ultraviolet ray through the resin, the resin can be easily cured while the structure is being pressed. Therefore, the above effect can be easily obtained.

Furthermore, if a transparent electrode or the like is formed along the drive electrode on a smooth surface formed by the resin and the drive electrode, the manufactured liquid crystal element has a drive voltage applied to the drive electrode and the transparent electrode. Can be applied to drive. Therefore, the resistance value is reduced, the delay of the voltage waveform is eliminated, and a liquid crystal element capable of coping with high definition can be obtained as compared with the case of driving only by the transparent electrode. Such an effect becomes remarkable when the drive electrode is a metal electrode.

Further, as described above, when the driving electrode and the transparent electrode are provided side by side, the delay of the voltage waveform is eliminated, so that it is not necessary to form the transparent electrode thick, and the transmittance of the transparent electrode is reduced. There is no possibility that the electrode will be lowered and recognized. Further, since the drive electrode is formed on the back side of the transparent electrode, even if an alignment control film is formed on the surface of the transparent electrode, the alignment control film does not have unevenness, and the There are no concerns about differences or crosstalk. Therefore, according to the present invention, such a liquid crystal element having excellent display quality can be manufactured.

Furthermore, conventionally, the thickness of the drive electrode is 2 μm.
If it is m or more, the amount of sink marks becomes large and it is difficult to secure the flatness of the resin surface, but according to the present invention, there is no such problem. Therefore, the thickness of the drive electrode can be increased, so that the resistance of the liquid crystal element can be reduced, and a liquid crystal element capable of achieving higher definition can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining the structure of a conventional liquid crystal panel.

FIG. 2 is a cross-sectional view for explaining the structure of another conventional liquid crystal panel.

FIG. 3 is a diagram for explaining an example of a conventional method for manufacturing a liquid crystal panel.

FIG. 4 is a diagram for explaining a conventional problem associated with resin shrinkage upon curing.

FIG. 5 is a diagram for explaining the manufacturing method of the liquid crystal panel according to the present invention, particularly for explaining the wiring substrate forming process to the first peeling process.

FIG. 6 is a detailed cross-sectional view for explaining the shape of resin and the like in the first pressurizing step.

FIG. 7 is a detailed cross-sectional view for explaining the shape of the resin and the like after the completion of the first peeling step.

FIG. 8 is a diagram for explaining the manufacturing method of the liquid crystal panel according to the present invention, particularly for explaining the process from the second resin supply process to the second peeling process.

FIG. 9 is a detailed cross-sectional view for explaining the shape of the resin and the like after completion of the second peeling step.

FIG. 10 is a sectional view for explaining the structure of another press machine.

[Explanation of symbols]

10 Embedded Wiring Board 11 Glass Substrate (Base Substrate) 12, ... Metal Electrode (Drive Electrode) 13, 13L, 13S UV Curing Resin (Resin) 21 Smooth Plate (Second Pressing Member) 23 Recess 25 Press Machine 25U, 25D Upper and lower plates (ram) 26 Transparent substrate 31 Smooth plate (first pressing member) 31a Smooth plate member 31b Elastic film 35 Press machine 35U, 35D Upper and lower plates (ram) A ₁ Wiring board A ₂ Pressurized body ( Structure) A ₅ Pressurized body (structure) P ₂ Liquid crystal panel (liquid crystal element)

Claims (14)

[Claims] 1. A wiring board forming step of forming a plurality of drive electrodes on a surface of a base board to form a wiring board, and a first resin supplying step of supplying a liquid resin to a portion where the drive electrodes are formed. A first pressurizing step of filling a resin into a gap between the plurality of drive electrodes based on pressurizing a surface of the drive electrode via a first pressurizing member, and curing the filled resin. A method for manufacturing a liquid crystal element, comprising: a first resin curing step; and a peeling step of peeling the first pressure member from the wiring board, wherein the first pressure member is a smooth plate-shaped member. And an elastic elastic film covered with the plate-shaped member, and in the first pressurizing step, a depression is formed in the resin by pressing with the elastic film, In the resin curing process, the resin has a dented state. Surface of the drive electrode through a second resin supply step of curing a fat and newly supplying a liquid resin into the recess of the resin, and a smooth second pressure member not covered with an elastic film. A second pressurizing step of filling the recess with resin based on pressurizing the second resin, a second resin curing step of curing the resin supplied in the second resin supplying step, and the second applying step. A method of manufacturing a liquid crystal element, wherein a peeling step of peeling the pressure member from the wiring board is sequentially performed after the peeling step. 2. The method for manufacturing a liquid crystal element according to claim 1, wherein the resin filled in the gap between the drive electrodes is completely cured in the first resin curing step. 3. The depth of the recess is in the range of 0.2 to 1.0 μm, and the thickness of the resin disposed in the gap between the drive electrodes after the second resin curing step is: 3. The method for manufacturing a liquid crystal element according to claim 1, wherein the thickness is 1.0 μm or more. 4. The elastic film of the first pressure member is
The liquid crystal element manufacturing method according to claim 1, wherein the liquid crystal element is formed by applying a predetermined solution to the surface of the plate-shaped member and heating it. 5. The elastic film of the first pressure member is
The method for producing a liquid crystal element according to claim 1, which is formed by adhering a flexible film. 6. The first resin supply step, the first resin
The liquid resin is supplied to the portion where the drive electrode is formed by dropping the resin on the pressure member and overlapping the first pressure member on which the resin is dropped onto the wiring board. The method of manufacturing a liquid crystal element according to claim 1, wherein the liquid crystal element is manufactured. 7. The structure of the wiring board and the pressing member is disposed between a pair of rams of a press in either one or both of the first pressing step and the second pressing step. 7. The method for producing a liquid crystal element according to claim 1, wherein the structure is pressed by the pair of rams. 8. The first pressurizing step and the first resin curing step are simultaneously performed, and the resin is cured while the surface of the resin is pressed by the elastic film to form a recess. The method for producing a liquid crystal element according to claim 1, wherein the liquid crystal element is produced. 9. The second pressurizing step and the second resin curing step are performed at the same time, and the surface of the drive electrode is pressed by the second pressurizing member, The method of manufacturing a liquid crystal element according to claim 1, wherein the filled resin is cured. 10. The resin is a UV curable resin that is cured by being irradiated with ultraviolet rays, and the resin is irradiated with ultraviolet rays in the first resin curing step and the second resin curing step. 10. The method for producing a liquid crystal element according to claim 1, wherein the resin is cured based on the above. 11. In either or both of the first resin curing step and the second resin curing step,
A transparent substrate is interposed between any one of the pair of rams and the structure, and the resin is irradiated with ultraviolet rays through the transparent substrate while the structure is being pressed. The method for manufacturing a liquid crystal element according to claim 10, wherein 12. The liquid crystal device according to claim 1, wherein the resin is a thermosetting type, and the resin is cured by heating. Production method. 13. The method of manufacturing a liquid crystal element according to claim 1, wherein the drive electrode is a metal electrode. 14. A transparent electrode is formed on the surface formed by the resin and the drive electrode, the transparent electrode being formed after the second resin curing step and along the drive electrode. Item 14. A method for manufacturing a liquid crystal element according to any one of items 1 to 13.