JPH08248436A - Liquid crystal display device and its production - Google Patents

Abstract

PURPOSE: To decrease deformation of a substrate and to prevent production of air bubbles in a liquid crystal layer and to prevent coloring or irregular color in a display part by forming a supporting pillar in the outside of a sealing part of the edge part of substrates facing each other in a liquid crystal display device. CONSTITUTION: A supporting pillar 9 comprising a conductive ink is formed in the outside of a sealing material 6 which seals the liquid crystal layer 5 housed between an upper substrate 1 and a lower substrate 2. This supporting pillar 9 prevents bending of substrates 1, 2 caused by contracts when the molding material 8 is hardened, which decreases changes in the thickness of the liquid crystal layer. The supporting pillar 9 is formed at the same time when a conductive connecting part of the liquid crystal panel is produced and hardened with the sealing material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a technique for improving the structure of a peripheral portion of a substrate in a liquid crystal display body.

[0002]

2. Description of the Related Art In a conventional liquid crystal display device, a liquid crystal layer is enclosed between two substrates, and a voltage is applied between electrodes formed opposite to each other on the front and back sides of the liquid crystal layer so that the liquid crystal in the layer is The arrangement is changed to realize various displays. FIG. 7 shows an enlarged cross section of a substrate end portion of a liquid crystal display device of one type among these devices, and FIG. 8 shows a perspective plane showing the entire structure.

The upper substrate 1 and the lower substrate 2 are transparent glass plates, and transparent electrodes 3 and 4 each having a predetermined pattern are formed on the inner surfaces of the two substrates facing each other. A liquid crystal layer 5 is filled between the upper substrate 1 and the lower substrate 2 and sealed with a sealing material 6.

The lower substrate 2 extends more laterally than the upper substrate 1, and an electrode pad 4a constituting an external electrode conductively connected to the transparent electrode 4 is formed on the surface thereof. The electrode pad 4a is brought into contact with the footed insertion pin 7 attached so as to sandwich the lower substrate 2, and is connected to an external wiring substrate or the like. The insertion pin 7 with feet has its elastic jaw 7
The lower substrate 2 is mounted so as to be sandwiched by a and 7b, and this mounting portion is fixed by a molding material 8.

A plurality of electrode pads 4a are arranged on the end portion of the lower substrate 2 with a predetermined minimum interval, and the lower substrate 2
Is connected to the transparent electrode 4 formed on the inner surface of the. On the other hand, as shown in FIG. 8, a plurality of electrode pads 3 a are also formed on the end portion of the lower substrate 2, and the transparent electrode 3 formed on the inner surface of the upper substrate 1 via the conductive connection portion 10. It is connected. The above device is a segment type liquid crystal display device, and the transparent electrode 3 is used as a common electrode and the transparent electrode 4 is used as a segment electrode.

[0006]

In the above-mentioned conventional liquid crystal display device, in the electrode lead-out portion where the lower substrate 2 extends outward from the end of the upper substrate 1, the electrode pads 3a and 4a and the insertion pins with feet are provided. In order to fix the conductive connection portion with 7 and to prevent the electrolytic corrosion of the electrode pad 4a and the like, it is necessary to fill and cover the resin molding material 8 between the upper substrate 1 and the lower substrate 2. Such a coating process is not limited to the conductive connection method using the footed insertion pins 7 as described above, but is also a method of conductively connecting the pad portion on the circuit board via a bonding wire, a flexible board or a heat treatment. The same applies to a method of electrically connecting to the end of the seal through a conductive adhesive or the like.

The reason why such a resin mold coating process is performed is that the connecting portions of various parts such as the above-mentioned insertion pins 7 with legs, bonding wires, flexible substrates, heat seals, etc., which are bonded to the electrode pads 3a, 4a are electrically connected. Coating (conductive connection part protection mold), fixing the connection parts such as flexible substrates and heat seals, and strengthening their rigidity (reinforcement mold), water on two or more adjacent electrode pads 3a, 4a. To prevent electrical contact caused by the potential difference between the electrode pads when liquid such as liquid adheres (mold for corrosion prevention), and to prevent other corrosion and erosion of the liquid crystal panel structure (mold for improving durability and corrosion resistance), etc. is there.

Although these molds are often applied to the conductive connecting portions where the electrode pads 3a and 4a are formed as described above, inevitably in the molds for the purpose of reinforcement and durability as described above. It is also applied to parts other than the conductive connection part. Therefore, the resin coating with the molding agent may be performed on the entire circumference of the peripheral edge of the liquid crystal panel.

When such a mold, that is, a resin coating is performed, generally, the ends of the upper and lower substrates are attracted to each other due to the curing shrinkage of the mold resin, the ends of the substrates are deformed inward, and the reaction thereof causes the sealing material 6 to move. The space between the upper and lower substrates inside is widened and the inside becomes negative pressure, and low temperature bubbles and shock bubbles are easily generated in the liquid crystal layer.

Further, since the cell thickness of the liquid crystal panel changes due to the stress caused by the resin coating, coloring and color unevenness are likely to occur. This change in cell thickness is likely to increase particularly near the seal portion, and it is necessary to cover the peripheral portion of the liquid crystal panel with a black mask in order to avoid deterioration of display quality in this portion. Since the formation of this mask reduces the liquid crystal display area, the relative manufacturing cost of the liquid crystal display is increased. Such coloring or color unevenness is a serious problem, especially in a large-capacity liquid crystal panel, since the cell thickness may change greatly within the panel surface.

The cause of the above-mentioned stress that causes the deformation of the substrate is not limited to the above-mentioned contraction stress from the molding material, but is caused by the mechanical contact when the liquid crystal panel is manufactured or when the liquid crystal panel is incorporated into various devices. Moreover, it may be generated by shock or vibration applied to various devices in which the liquid crystal panel is incorporated.

Therefore, the present invention solves the above-mentioned problems, and an object thereof is to provide a novel structure in a liquid crystal display device which can prevent the deformation of the substrate by supporting and dispersing the stress acting on the substrate. Especially.

Another object of the present invention is to improve the display quality of the liquid crystal display device by reducing the dimensional error of the liquid crystal cell structure due to the stress from the outside.

A further object of the present invention is to improve the yield of products by preventing the deterioration of the quality of the liquid crystal display device due to the mold formation.

A further object of the present invention is to realize a method which does not require any special design change or additional manufacturing process in order to prevent the deformation of the substrate due to mold formation.

[0016]

Means for Solving the Problems The measures taken by the present invention to solve the above problems are as follows. Two substrates, at least one of which is transparent, and a liquid crystal layer housed between the substrates, A liquid crystal display device comprising: a seal portion formed between the substrates so as to surround the liquid crystal layer; and a supporting column that connects the substrates outside the seal portion. Here, the display principle of the liquid crystal layer may be any, and the materials of the seal portion and the supporting columns are not particularly limited. Further, the support columns can be formed in any number and any shape as required.

According to this means, by forming the support column on the outer side of the seal portion, the deformation of the substrate around the seal portion as a fulcrum which may occur due to various causes is reduced, so that the distance between the substrates can be changed. It is possible to reduce the generation of bubbles in the liquid crystal layer, the coloration of the display body, and the occurrence of color unevenness due to the generation.

Here, in particular, when the molding material for covering the end portion of the substrate is provided, the stress applied to the substrate is reduced because the contraction force of the molding material is supported by the supporting column, and the deformation of the substrate is suppressed. Is effective. In this case, as the molding material, the molding material is for fixing a connection component, such as a connection pin or a connection wire, which is conductively connected to an external terminal for applying an electric field to the liquid crystal layer. There are those for reinforcing a flexible substrate that is conductively connected to a plurality of external terminals for applying an electric field, those for preventing electric contact of the external terminals, and the like.

In these cases, it is preferable that the support columns are further formed at the end of the substrate. The support pillars formed at the ends of the substrate exert the greatest resistance against the stress applied to the ends of the substrate.

Further, it is preferable that the support pillar is formed of a conductive paste used for conductive connection between wirings in the apparatus. By forming the support pillars with a conductive paste, the support pillars are connected to the conductive connection part in the liquid crystal panel (in particular, the upper and lower connection parts for connecting the conductors formed along the opposite substrate across the liquid crystal cell). ) At the same time, it can be formed at the same time, or can be used also as the support pillar and the conductive connection portion, so that it can be manufactured without changing the number of steps and the details of the steps, and the manufacturing cost can be suppressed.

Further, it is desirable that the conductive paste is a conductive ink containing carbon. By using the carbon-containing conductive ink, the support columns can be easily and accurately formed by a printing method.

Further, it is preferable that the supporting columns are formed of a material containing a phenol resin as a main component. By forming the support column with a material whose main component is phenol resin,
Since the adhesive strength to the substrate is relatively low and it has appropriate flexibility, it is easy to cut the substrate when manufacturing a liquid crystal display device, and when the substrate is cut at the supporting pillar forming part, the substrate is cut. The risk of cracking can be avoided.

Further, it is preferable that the supporting column is made of a material exhibiting an adhesive force lower than that of the raw material forming the seal portion. By forming the support pillars with a material that has a lower adhesive strength than the raw material that forms the seal portion, the substrate can be easily cut at the time of manufacturing the liquid crystal display device, and the substrate is cut at the support pillar formation portion. In this case, the risk of breaking the board can be avoided.

Further, it is preferable that the support column is formed of a material having the same hardening characteristics as the raw material forming the seal portion. By forming the support column with a material having the same hardening characteristics as the raw material forming the seal portion, the support column can be cured at the same time as the seal portion during manufacturing of the liquid crystal display device. Compared with the case of separately curing the part, it can be manufactured as it is with the positioning accuracy of the substrate set when curing the seal part,
It is possible to avoid an increase in the number of manufacturing processes and process time.

As a method of manufacturing a liquid crystal display device, further, at least one of the two transparent substrates is
A seal portion is formed so as to surround a region for accommodating a liquid crystal layer, and a support column for connecting the substrates is provided outside the seal portion, and then an end portion of the substrate is covered with a molding material. It is a thing. In this manufacturing method, the above-mentioned effects can be easily obtained only by providing the supporting columns.

Here, it is preferable that the seal portion and the support column are made of a material having the same hardening characteristics, and the seal portion and the support column are simultaneously cured. By setting the sealing portion and the supporting column to have the same curing characteristics, for example, the same characteristics such as thermosetting property or photocuring property, it is possible to perform the curing process in the same process, and it is necessary to provide a new curing process. Disappear.

Further, it is preferable that the conductive connecting portion for connecting the electrode formed on the substrate and the external terminal and the supporting column are simultaneously provided with the same material. By forming the support pillar at the same time as the conductive connection part with the same material, both can be placed in the same process.
Since it can be formed, the above-described effects can be obtained by only changing the formation pattern of the conductive connection portion without newly providing a manufacturing process for arranging and forming the support pillar.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a liquid crystal display device according to the present invention will be described with reference to the drawings. The liquid crystal display device of the present invention is used for various well-known liquid crystal display devices such as TN type, STN type, GH type, etc., for display parts of a relatively small area such as watches, calculators, etc. Various liquid crystal display devices are conceivable up to large-capacity panels used in televisions and the like.

FIG. 1 is an enlarged view showing a partial cross section of a first embodiment of a liquid crystal display device according to the present invention. In this embodiment, the upper substrate 1, the lower substrate 2, the transparent electrodes 3 and 4, the liquid crystal layer 5, the sealing material 6 and the electrode pad 4a, which are formed in the same manner as in the above-mentioned conventional example, are provided, and the insertion pin with a foot 7 is placed below. After being mounted on the electrode pad 4a of the side substrate 2, it is fixed by the molding material 8. Depending on the liquid crystal display method, a polarizing plate may be arranged outside the upper and lower substrates.

In this embodiment, a support column 9 made of a conductive ink containing carbon particles is formed between the upper substrate 1 and the end of the lower substrate 2. The support pillars 9 are formed at the same time as the upper and lower substrates are assembled before the molding material 8 is supplied, as will be described later.

FIG. 2 is a perspective view of this embodiment as seen from above, in which the liquid crystal layer 5 is provided between the upper substrate 1 and the lower substrate 2.
Are sealed by the sealing material 6. A transparent electrode 4 (not shown) having a predetermined pattern formed on the lower substrate 2 is conductively connected to an electrode pad 4a formed on the end surface of the lower substrate 2. Further, the transparent electrode 3 (not shown) having a predetermined pattern formed on the inner surface of the upper substrate 1 is an electrode formed on the lower substrate 2 via the upper and lower connecting portions 10 made of conductive (carbon) ink. It is conductively connected to the pad 3a.

The electrode pads 3a and 4a are conductively connected to an external structure such as a printed circuit board through the above-mentioned footed insertion pins 7. Here, the right end of the upper substrate 1 and the lower substrate 2
The support pillars 9 are formed at predetermined intervals between and, so that the space between the upper substrate 1 and the end portions of the lower substrate 2 can be sufficiently supported.

Since the supporting columns 9 are formed to support between the end portion of the upper substrate 1 and the lower substrate 2, the supporting columns 9 are dispersed evenly in the necessary portions as described above. Preferably. In the present embodiment, it is formed only on the right end portion of the liquid crystal panel, but it may be formed on one or more other end portions if necessary.

In this embodiment, since the support pillar 9 is made of conductive ink, if possible in terms of circuit configuration, the support pillar 9 is formed.
Similarly to the upper and lower connecting portions 10, can also be used as a conductive connecting portion. For example, in order to connect between the transparent electrode 3 formed on the inner surface of the upper substrate 1 and the electrode pad 3a formed on the right end surface of the lower substrate 2, the upper and lower connecting portions 1
It can be used instead of 0 or with the upper and lower connecting parts 10.

In this embodiment, the support pillars 9 are formed on the formation portions of the electrode pads 3a and 4a in conformity with the formation intervals of the electrode pads 3a and 4a. However, as can be seen from the fact that the supporting pillars 9 are also formed on the portions that are not on the electrode pads, the positions at which the supporting pillars 9 are formed are not limited to the electrode pads, and the supporting pillars 9 may be formed at arbitrary positions. You can However, when the support pillar 9 is made of a conductive material, care must be taken so that the support pillar 9 does not cause a short circuit between adjacent electrode pads. In order to prevent a short circuit between the adjacent electrode pads, the diameter of the support pillar 9 may be formed smaller than the distance between the electrode pads, but a simpler method is to form it on the electrode pads as in the above embodiment. It is to be.

Further, the support pillar 9 may be formed in an extended shape along the end portion of the substrate instead of forming the support pillar 9 in a circular cross section as in the present embodiment. However, when the support pillars 9 are formed in the electrode pad formation region as in the above embodiment,
In order to prevent a short circuit between the adjacent electrode pads, it is necessary to form the support pillar with an insulator or to interpose an insulator with the electrode pad.

Further, it is most preferable to form the support column 9 at the end portion of the upper substrate 1 as in the above-mentioned embodiment in order to enhance the resistance against stress, but it is only required to be outside the sealing material 6. The same effect can be achieved to some extent.

The above conductive ink is most preferable as the material of the supporting column in this embodiment. This is a mixture of conductive powder such as carbon in a suitable solidifying component.
As the solidifying component, for example, phenol resin is included. This conductive ink is excellent in terms of ease of manufacturing and cost reduction because it can be formed of the same material as that used for the conductive connecting portion in the same process.
Further, since the phenol resin has a weak adhesive force and is relatively soft, it becomes easy to cut the substrate at the time of manufacturing as will be described later, and further, it is possible to prevent the substrate from cracking at the time of cutting the substrate.

As the conductive material forming the support pillar,
In addition to the above conductive ink, various conductive pastes such as silver brazing can be used. However, the material of the supporting column according to the present invention does not necessarily have to be conductive, and may be insulating. The material of the supporting columns is preferably one that can be cured after being placed in a semi-fluid state in order to facilitate the selective placement of the supporting columns. For example, a thermosetting resin, a photocurable resin, or the like can be used. Can be used.

On the other hand, the characteristic of the supporting column is that it has at least a sufficient supporting strength after curing, the adhesive force to the substrate is not always necessary, and the adhesive force is preferably weak. This is because, as will be described later, since the support pillars are formed at the ends of the substrate, it is desired that the adhesive strength be such that the cutting is not obstructed in the step of cutting the substrate. If the adhesive strength is large, it is difficult to cut the substrate across the bonded portion of the support column, and even if it is cut, the substrate cannot be separated and there is a risk of damaging the substrate end. Further, the strength of the adhesive force is related to the shrinkage rate at the time of curing, and it is desirable that the material of the support column has a weak adhesive force and a low shrinkage rate from the viewpoint of suppressing the deformation and distortion of the substrate.

FIG. 3 shows a second embodiment of the liquid crystal display device according to the present invention. Also in this embodiment,
The upper substrate 1, the lower substrate 2, the transparent electrodes 3 and 4, the electrode pads 4a, the liquid crystal layer 5, the sealing material 6 and the support pillars 9 are the same as those in the above-mentioned embodiment, and the description thereof will be omitted.

In this embodiment, the heat seal 20 is bonded onto the plurality of electrode pads 3a and 4a arranged in parallel. In the heat seal 20, the wiring pad 2 formed on the lower surface of the flexible thin resin sheet at a formation pitch that matches the formation pitch of the electrode pads 3a and 4a.
1 is formed, and an anisotropic conductive layer (not shown) is deposited on the surface of the wiring pad 21. This anisotropic conductive layer is made by dispersing conductive particles in, for example, a thermosetting resin, and exhibits conductivity only in the bonding direction by bonding with appropriate heat and pressure.

The surface of the heat seal 20 on which the wiring pad 21 is formed is brought into contact with the electrode pads 3a and 4a and heated by applying a predetermined pressure, so that the electrode pads 3a and 4a and the wiring pad 21 can be conductively connected. it can. After that, in order to mechanically reinforce the connection portion of the heat seal 20 and to cover the electrode pads 3a and 4a, sealing is performed with the molding material 18.

Also in this embodiment, as in the first embodiment, the end portion of the upper substrate 1 is pulled toward the lower substrate 2 by the contracting force when the molding material 18 is cured. Although trying to deform, since the end portion of the upper substrate 1 is supported by the support columns 9, the upper substrate 1
Deformation is suppressed. In this embodiment, since the molding material 18 is to reinforce the connection portion of the heat seal 20, it is required that the molding material 18 has high adhesive strength and hardness after curing. Since the contraction rate is also high, the stress applied to the substrate end portion at the time of curing the molding material is also large, so that the formation of the support columns 9 is more effective.

FIG. 4 shows a first embodiment of a method of manufacturing a liquid crystal display device according to the present invention. As shown in FIG. 4A, a transparent electrode pattern (not shown) is formed on the transparent substrate 2 made of glass, and the sealant 11 is applied onto the transparent electrode pattern at a position corresponding to the periphery of the liquid crystal display section. Then, the conductive ink 12 is selectively placed on the surface of the lower substrate 2 by screen printing. The conductive ink 12 is arranged at a necessary position of the conductive connection portion (for example, the upper and lower connection portions 10 in FIG. 2) and a plurality of positions along the sealant 11 outside the liquid crystal display portion.

Next, as shown in FIG. 4B, the upper substrate 1 is covered over the sealant 11 and the conductive ink 12,
The upper substrate 1 and the lower substrate 2 are fixed by a dedicated jig so that the distance between them is a predetermined value (for example, several to several tens of μm). Then, in a heating furnace with a dedicated jig, 150 to 20
A heat treatment at about 0 ° C. is performed to heat-harden the sealant 11 and the conductive ink 12 at the same time, and the sealant 6 and the support pillar 9 are formed.
To form.

Further, as shown in FIG. 4C, the upper and lower substrates are separated for each liquid crystal display portion, and the upper substrate 1 is cut to provide external terminal portions as shown in FIG. 4D. At the time of cutting the upper substrate 1, if the adhesive force of the support columns 9 to the upper substrate 1 is too large, the support columns 9 are arranged near the substrate end planned position, so that the support columns 9 stick out to the cutting line. As a result, it becomes difficult to cut and the cutting line corrugates in a shape that bypasses the support pillar 9. It is difficult to strictly adjust the amount of the conductive ink 12 by a low-cost deposition method by printing, and the amount of the conductive ink 12 is adjusted in relation to the distance between the substrates when the upper and lower substrates are aligned. This is because it is more difficult to control the diameter of the support column 9 and the amount of protrusion from the planned cutting line.

However, in this embodiment, since the support column 9 made of the conductive ink containing the phenol resin has a relatively low adhesive force and the adhesive force is considerably weaker than that of the sealant 11,
Even if the conductive ink extends beyond the substrate edge planned position, the upper substrate 1 can be cut without any problem.

The liquid crystal panel thus formed is shown in FIG.
Insert the footed insertion pin 7 shown in (1), apply a molding material 8 made of an ultraviolet curable resin or the like from above the external terminal portion, and cure by light irradiation. At this time, even if contraction occurs due to the curing of the molding material 8, since the support pillar 9 is formed between the end portion of the upper substrate 1 and the lower substrate 2, the contraction force is absorbed by the support pillar 9. Thus, the stress applied to the substrate itself is reduced, and the deformation of the substrate is prevented.

When a liquid crystal panel was prototyped without introducing the liquid crystal between the upper substrate 1 and the lower substrate 2, the substrate gap was swollen by about 1 μm at maximum in the conventional one, but in the present embodiment, the substrate gap is increased. Almost no bulge is seen, and when a liquid crystal is actually introduced and prototyped, it is 0.2-
Although it swelled by about 0.5 μm, in each of the above-described embodiments, the change in the substrate interval is 0.1 μm or less at the maximum, and the product yield is significantly improved. For example, TN (Twisted Nemat
In the case of ic) type liquid crystal display device, the change in substrate spacing is 1 μm
If it exceeds the range, coloring and color unevenness are clearly generated, so that even a change of 0.2 to 0.5 μm as a product poses a problem in display quality. Further, in STN (Super Twisted Nematic) type liquid crystal, the color tone is affected even if the change in the substrate spacing is about 0.1 μm. Therefore, in the related art, the display quality of the TN type liquid crystal has a problem, and the fatal defect has occurred especially in the STN type liquid crystal, but the present invention has brought about a great improvement of the display quality.

Next, with reference to FIG. 5, a second embodiment of the method of manufacturing the liquid crystal display device according to the present invention will be described. In this embodiment, as shown in FIG. 5A, internal surface structures 33 and 34 such as transparent electrodes and alignment films are formed on the inner surfaces of the two transparent substrates 31 and 32. Internal surface structure 33,
34, a common electrode is formed in the region a and a region b is formed.
A segment electrode is formed in the center, and electrode pads are formed on the left and right ends of the segment electrode. As shown in the drawing, the regions a and b are alternately formed on the inner surfaces of the transparent substrates 31 and 32, and the region a formed on the inner surface of the transparent electrode 31 is formed on the inner surface of the transparent electrode 32. Area b formed on the inner surface of the transparent electrode 31 facing the area b
Are opposed to the region a formed on the inner surface of the transparent electrode 32.

Next, a sealant 35 formed so as to surround the liquid crystal layer accommodating region and a phenol resin 36 formed on the outside of the sealant 35 are sandwiched between both substrates by using a jig or the like. The sealing agent 35 and the phenol resin 36 are cured by heating the entire body in a state of being held at a predetermined interval.

The transparent substrates 31 and 32 of the panel continuum constructed in this manner are provided in each of the regions a and b.
By cutting each, the portion corresponding to the region a of the transparent substrate is cut into the upper substrate (small substrate) 1 as shown in FIG.
Then, a liquid crystal cell in which the lower substrate (large substrate) 2 corresponds to the region b is formed. This liquid crystal cell is shown in FIG.
As shown in FIG. 2, there are extending portions of the lower substrate 2 on both sides of both ends of the upper substrate 1, and these portions serve as common electrodes formed on the inner surfaces of the upper substrate 1 and the lower substrate 2. Electrode pads 3a and 4 similar to those of the first embodiment connected to the transparent electrode 3 and the transparent electrode 4 as a segment electrode.
a is formed.

The liquid crystal cell constructed as described above is introduced into the liquid crystal display member shown in FIG. 5 (d) by introducing the liquid crystal into the portion surrounded by the thermosetting sealing material 6 and the supporting columns 19 on the outside thereof. Is formed.

In this liquid crystal display, the lower substrate 2 extends outside both ends of the upper substrate 1, and the electrode pads 3a and 4a are formed on the extended regions to serve as external terminal portions. Support columns 19 are formed on the outer side portions of the sealing material 6 desired for the external terminal portions on both sides. Since the support pillars 19 are made of insulating phenol resin, they can be formed in a size and arrangement that are irrelevant to the formation positions of the electrode pads 3a and 4a. Further, in this embodiment, it is necessary to cut the transparent substrates 31 and 32 in the vicinity of the site where the support columns 19 are formed. However, since the support columns 19 made of phenolic resin have a weak adhesive force to the transparent substrate, the support columns are provisionally supported. The transparent substrate can be separated without any trouble even if the protrusions 19 slightly extend to the adjacent region.

According to the second embodiment of this manufacturing method, it is necessary to provide a printing or coating process for forming the insulating support pillars 19, but the support pillars 10 are insulators. Therefore, there is an advantage that the support column 19 can be formed in an optimum shape and arrangement for preventing the substrate deformation of the liquid crystal display body without being restricted by the positional relationship with the electrode pad. The structure in which the regions a and the regions b are alternately repeated as described above is preferable for mass production of liquid crystal display devices and is effective in reducing the manufacturing cost.

FIG. 6 shows an example in which the liquid crystal display is connected to a circuit board 30 on which a liquid crystal drive circuit is mounted via a flexible board (heat seal) 20.
Electrode pads 3a formed on the external terminals of the liquid crystal display,
The end portion of the heat seal 20 is placed on 4a, and is heated and pressed to adhere to the wiring pad 21 formed on the lower surface (the back surface in the figure) of the heat seal 20 through the anisotropic conductive adhesive layer. To be done. The molding material 18 is the electrode pad 3
The end portion of the heat seal 20 adhered on a and 4a is fixed to the liquid crystal display body and is attached to reinforce the connection portion.

As shown by the various embodiments described above and as understood by those skilled in the art to which the present invention pertains, the present invention provides a connection structure for external terminal portions of a liquid crystal display and a liquid crystal cell. It can be widely applied regardless of the structure and the covering area of the molding material.

In each of the above-described embodiments, the case where the external terminal portion is covered with the molding material has been mainly described, but the present invention is not limited to such a case, and various types of liquid crystal display devices can be applied to various cases. It has an excellent effect that it is possible to prevent a change in the distance between the substrates due to the external force.

[0060]

As described above, the present invention has the following effects.

According to the first or the fourth aspect of the invention, since the support column is formed outside the seal portion, the deformation of the substrate around the seal portion as a fulcrum which may occur due to various causes is reduced. It is possible to reduce the occurrence of bubbles in the liquid crystal layer, the coloring of the display body, and the occurrence of color unevenness due to the change in the interval between the two.

According to the second aspect, since the supporting pillars support the contracting force of the molding material, the stress applied to the substrate is reduced, and the deformation of the substrate is suppressed, which is effective.

According to the third aspect, the support columns formed at the end portions of the substrate exert the greatest counter force against the stress applied to the end portions of the substrate.

According to the fifth aspect of the present invention, the support pillars are formed of the conductive paste, so that the support pillars are formed along the conductive connection portion in the liquid crystal panel (particularly along the substrate on the opposite side across the liquid crystal cell). Since it can be formed at the same time as the upper and lower connection parts for connecting between conductors, and can also be used as the support pillar and the conductive connection part, it can be manufactured without changing the number of processes and the process contents, and the manufacturing cost is suppressed. it can.

According to the sixth aspect, by using the carbon-containing conductive ink, the support pillar can be easily and accurately formed by the printing method.

According to the seventh aspect, since the supporting column is formed of a material containing a phenol resin as a main component, the adhesive strength to the substrate is relatively low and the supporting column has appropriate flexibility. It is possible to easily cut the substrate at the time of manufacturing and avoid the risk of breaking the substrate when the substrate is cut at the support pillar forming portion.

According to the eighth aspect, by forming the supporting column with a material exhibiting a lower adhesive force than the raw material forming the seal portion, the substrate can be easily cut when manufacturing the liquid crystal display device. It is possible to avoid the risk of breaking the substrate when the substrate is cut at the support pillar forming portion.

According to the ninth aspect, the support pillar is formed of a material having the same curing characteristics as the raw material forming the seal portion, so that the support pillar is cured at the same time as the seal portion at the time of manufacturing the liquid crystal display device. Therefore, compared to the case where the support pillar and the seal part are separately cured, it is possible to manufacture with the same positioning accuracy of the substrate set when the seal part is cured, and to avoid an increase in the number of manufacturing processes and process time. You can

According to the thirteenth aspect, the above effect can be easily obtained only by providing the support columns.

According to the fourteenth aspect, by making the seal portion and the supporting column have the same hardening characteristics, for example, the same characteristics such as thermosetting property or photocuring property, it is possible to perform the hardening process in the same step. Therefore, it is not necessary to provide a new curing step.

According to the fifteenth aspect, since the support pillars are formed of the same material as the conductive connection portions at the same time, both of them can be arranged and formed in the same process.
The above effects can be obtained by simply changing the formation pattern of the conductive connection portion without newly providing a manufacturing process for formation.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view showing a partial cross section of a first embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is a perspective plan view showing a planar structure of the same embodiment.

FIG. 3 is an enlarged cross-sectional view showing a partial cross section of a second embodiment of a liquid crystal display device according to the present invention.

FIG. 4 is a process explanatory view showing the manufacturing process of the first embodiment of the method of manufacturing a liquid crystal display device according to the present invention.

FIG. 5 is a process explanatory view showing the manufacturing process of the second embodiment of the method of manufacturing a liquid crystal display device according to the present invention.

FIG. 6 is a plan view showing a mounting structure of a liquid crystal display device formed by a second embodiment of the manufacturing method.

FIG. 7 is an enlarged cross-sectional view showing a partial cross section of a conventional liquid crystal display device.

FIG. 8 is a perspective plan view showing a planar structure of a conventional liquid crystal display device.

[Explanation of reference numerals] 1 upper substrate 2 lower substrate 3,4 transparent electrodes 3a, 4a electrode pad 5 liquid crystal layer 6 sealing material 7 insertion pins with feet 8,18 molding material 9,19 support pillar 10 conductive connection portion 11 sealing material 12 Conductive ink 20 Heat seal

Claims (15)

[Claims] 1. Two substrates, at least one of which is translucent, a liquid crystal layer housed between the substrates, and a seal portion formed between the substrates so as to surround the liquid crystal layer, A liquid crystal display device, comprising: a support column that connects the substrates outside the seal portion. 2. The liquid crystal display device according to claim 1, further comprising a molding material that covers an end portion of the substrate. 3. The liquid crystal display device according to claim 1, wherein the support pillar is formed at an end portion of the substrate. 4. Two substrates, at least one of which is translucent, a liquid crystal layer housed between the substrates, and a seal portion formed between the substrates so as to surround the liquid crystal layer, A liquid crystal display device, comprising: a support pillar that connects between the substrates, which is formed at any end of the substrate to be sealed outside the sealing portion. 5. The liquid crystal display device according to claim 1, wherein the support pillar is formed of a conductive paste used for conductive connection between wirings in the device. 6. The liquid crystal display device according to claim 5, wherein the conductive paste is carbon-containing conductive ink. 7. The liquid crystal display device according to claim 1, wherein the support column is made of a material containing phenol resin as a main component. 8. The liquid crystal display device according to claim 1, wherein the support column is made of a material exhibiting an adhesive force lower than that of a raw material forming the seal portion. 9. The liquid crystal display device according to claim 1, wherein the support pillar is made of a material having a curing characteristic that is the same as that of the raw material that forms the seal portion. 10. The liquid crystal display device according to claim 2, wherein the molding material is for fixing a connection component that is conductively connected to an external terminal for applying an electric field to the liquid crystal layer. 11. The liquid crystal display device according to claim 2, wherein the molding material is for reinforcing a flexible substrate that is conductively connected to a plurality of external terminals for applying an electric field to the liquid crystal layer. 12. The liquid crystal display device according to claim 2, wherein the molding material is for sealing an electric contact of an external terminal for applying an electric field to the liquid crystal layer. 13. A seal portion is formed between two substrates, at least one of which is transparent, so as to surround a region for accommodating a liquid crystal layer, and the space between the substrates is provided outside the seal portion. A method of manufacturing a liquid crystal display device, comprising: providing a support pillar for connecting a substrate, and then coating an end portion of the substrate with a molding material. 14. The liquid crystal according to claim 13, wherein the seal portion or the pre-stage substance thereof and the support column or the pre-stage substance thereof are made of a material having the same curing characteristics, and the seal portion and the support column are simultaneously cured. Manufacturing method of display device. 15. The method according to claim 13 or 14,
A method of manufacturing a liquid crystal display device, in which a conductive connection portion that connects an electrode formed on the substrate and an external terminal and the support pillar are simultaneously disposed of the same material.