JPH07191341A - Packaging structure of liquid crystal panel and production of liquid crystal panel for realizing the same - Google Patents

Abstract

PURPOSE:To package the liquid crystal panel with high reliability at low cost. CONSTITUTION:An orientation film material 25 is formed outside an image display area 2 so that the edge of an anisotropic conductive film 17 on the side of the liquid crystal panel is on the orientation film material 25 when a flexible substrate 8 is connected through the anisotropic conductive film 17. Thus, the orientation film material 25 is interposed between the anisotropic conductive film 17 and a substrate to increase the adhesive strength between the surface of the substrate 3 and the anisotropic conductive film 17; and the entry of water, etc., from a border surface C is prevented to obtain high reliability and a resin for protection which protect the periphery of the connection part is eliminated to reduce the cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel mounting structure in which various circuit boards are mounted on the periphery of a liquid crystal panel, and a liquid crystal panel manufacturing method for realizing the same.

[0002]

2. Description of the Related Art Various types of mounting structures for liquid crystal display devices have been put into practical use. Here, a mounting structure most widely used at present will be briefly described. For more details, see "Hatada: Driver IC mounting technology, latest liquid crystal process technology (Semiconductor World special issue), (1992) P.
249 ”,“ Tsukagoshi et al .: Thermosetting anisotropic conductive film, Hitachi Chemical Technical Report, No.16 (1991-1) P.23 ”,“ Asano et al .: Development trend of anisotropic conductive film for liquid crystal displays, ”
Hitachi Chemical Technical Report, No.20 (1993-1) P.9 ”.

12 and 13 show a mounting structure of the most general liquid crystal display device, and FIG. 12 is a plan view thereof.
FIG. 13 is a sectional view taken along the line AA of FIG. 12 (a sectional view of a connecting portion in the peripheral portion).

A liquid crystal display device 1 having an image display area 2
Is formed by sealing the periphery of substrates 3 and 4 made of glass or the like, which are arranged to face each other, with a sealing material 5 and enclosing a liquid crystal 6 inside. In addition, a flexible substrate 8 on which an LSI (Large Scale Integrated Circuit) 7 for outputting an image signal to drive the liquid crystal display device 1 is mounted is disposed on the peripheral portion of the liquid crystal display device 1 (note that The entire flexible substrate 8 on which the LSI 7 is mounted is generally called TAB (tape automated bonding)). And the substrate 3,
A plurality of electrode terminals arranged in a matrix inside 4
By controlling the voltage between (not shown) by the image signal from the LSI 7, the orientation (tilt) of the liquid crystal 6 is changed to control the image displayed in the image display area 2.

Underlayer layers 9 and 10 made of Ta ₂ O ₅ or SiO ₂ are formed on the inner surfaces of the opposing substrates 3 and 4, respectively.
On the surface of the base film layers 9 and 10, thin film layers of various signal wirings,
A color filter layer, a black matrix layer, an insulating film layer, etc. are formed in multiple layers (FIGS. 12 and 13).
Omitted in). In the uppermost layer, alignment film layers 11 and 12 for initially aligning the molecular groups of the liquid crystal 6 are formed of polyimide or the like with a thickness of about 500 angstroms to 1000 angstroms. The base film layers 9 and 10 may or may not be formed.

On the other hand, on the TAB-mounted flexible substrate 8, lead wirings 13 for input signals and lead wirings 14 for output signals for inputting / outputting signals to / from the LSI 7 are formed, and bumps 15 are provided respectively. It is connected to the connection terminal of the LSI 7 via. The periphery of the connection between the LSI 7 and the lead wires 13 and 14 is covered with a protective resin 16. The lead wire 14 on the output side of the LSI 7 is connected to the panel-side terminal 18 formed on the substrate 3 using an anisotropic conductive film 17 (or a connecting material such as a photo-curing resin).
Here, the interface of the anisotropic conductive film 17 with the lead wiring 14 is B, while the interface with the panel-side terminal 18 is C.

On the substrate 3, the panel side terminal 1
Ta, Ti, which supplies the image signal from 8 to the image display area 2,
The lead-out wiring 19 formed of a thin film of Al, Cu, Mo or the like and SiO ₂ or Ta ₂ for protecting the surface of the lead-out wiring 19
An insulating film 20 made of O ₅ or the like is formed.

When the output side lead wiring 14 on the flexible substrate 8 and the panel side terminal 18 are connected by using the anisotropic conductive film 17 as described above, the anisotropic conductive film 17 is connected. At the time of heating / pressurization, it flows out and exudes to the tip D side of the flexible substrate 8. When this state is observed from above, as shown in FIG. 14, the anisotropic conductive film 17 flows out to the liquid crystal panel side from between the lead wirings 14 which are adjacent to each other. At that time, the anisotropic conductive film 1 flowed out between the lead wires 14 and 14 adjacent to each other.
A larger amount of the conductive particles 21 tend to gather at the above-mentioned flow-out point of 7 than at other points.

Further, in FIGS. 12 and 13, the upper side and the lower side around the connection portion formed by the anisotropic conductive film 17 are covered with protective resins 22 and 23 such as silicon or epoxy resin, respectively. In this way, the protective resins 22 and 23 prevent gas and moisture from penetrating into the connection portion of the anisotropic conductive film 17, and the adhesion at the interface B between the anisotropic conductive film 17 and the lead wire 14 and the anisotropic conductive film 17 are prevented. The mechanical strength, which is insufficient only by the adhesive force at the interface C between the panel terminal 18 and the terminal 18 on the panel side, is supplemented.

As a measure for improving the adhesion, it has been proposed to roughen the surface of the panel-side terminal 18 (Japanese Patent Laid-Open No. 62-153830).

[0011]

However, the conventional mounting structure of the liquid crystal display device has the following problems.

That is, observing the state after the reliability test in high temperature and high humidity such as 80 ° C. and 95% RH, the interface C between the anisotropic conductive film 17 and the panel side terminal 18 rather than the interface B with the lead wiring 14 is observed. Bubbles are generated on the surface and peeling occurs on the entire surface, resulting in poor connection. In addition, the above-mentioned connection failure state is, for example, connecting a connection terminal made of a test glass formed on a glass substrate and a transparent electrode (ITO: indium oxide) to a lead wiring of a flexible substrate through an anisotropic conductive film. It will be revealed by observing the sample through a glass substrate. The cause of the above-mentioned connection failure is
It is conceivable that water or the like easily enters from the surroundings through the interface C as the adhesive strength of the anisotropic conductive film 17 decreases.

Further, the main cause of the decrease in the adhesive strength of the anisotropic conductive film 17 is the coefficient of thermal expansion of the glass substrate 3 (usually 0.5).
Is about 8 × 10 ⁻⁶ / ° C.) is the coefficient of thermal expansion of the anisotropic conductive film 17.
(Usually about 7.5-20 × 10 ^-5 / ° C), so it is considered that thermal stress caused by heating at the time of connection or thermal stress during reliability test or thermal cycle has a large effect. Has been. For details, refer to the documents mentioned above.
, Mentioned in. From the above, firstly, it is desired to improve the connection state in a minute area.

Further, as described above, after the connection, the anisotropic conductive film 17 tends to exude to the tip of the lead wire 14 on the flexible substrate 8, and the conductive particles 21 tend to gather between the adjacent lead wires 14. As a result, the insulation reliability of the lead wiring 14 becomes low, and it is not possible to meet the recent demand for a finer connection pitch, which is required along with the high definition of the liquid crystal display panel. From the above, secondly, it is desired to improve the reliability of the insulating surface having a fine pitch.

Further, as described above, in order to prevent gas and moisture from entering the periphery of the connection portion and to supplement the mechanical strength of the adhesive surface, the periphery of the connection portion formed by the anisotropic conductive film 17 is a protective resin. It is necessary to cover with 22 and 23, which causes an increase in cost. Furthermore, this protective resin 22, 23
Must be applied to both sides around the connection. Therefore, the number of items such as front side coating process, curing process, substrate reversing process, back side coating process, curing process and protective resin coating process around the connection part increases, equipment investment increases and manufacturing cost is increased. Up occurs. From the above, thirdly, it is desired to suppress the cost increase when mounting the liquid crystal display device.

Incidentally, in the measure for improving the adhesion at the interface between the anisotropic conductive film and each terminal disclosed in Japanese Patent Laid-Open No. 62-153830, an etching step is required, and complicated steps such as masking and cleaning are required. This has to be done, resulting in increased man-hours and capital investment, resulting in higher costs. Further, in the above-mentioned measure for improving the adhesive force, the surface of the electrode terminal is merely roughened until it gets tired, and the glass substrate 3 itself or the underlying film layer 11 or the insulating film 20 exists between the electrode terminals, and the adhesiveness and the water resistance are improved. The sex is not so different from the conventional one.

Further, the lead wiring 19 on the liquid crystal panel side may be formed of a material having low water resistance such as Al or Mo. In that case, sufficient reliability may not be obtained with only the protective film of the insulating film 20. In addition, when the adhesion reliability between the alignment film layer 11 and the sealing material 5 cannot be obtained, the alignment film layer 11 and the sealing material 5 are considered in consideration of printing or coating accuracy of the alignment film layer 11 or the sealing material 5. It is necessary to provide a separation part having a distance d (= about 0.5 mm to 2 mm) between them. In that case, the size of the liquid crystal panel is increased only in the separated portion.

Therefore, an object of the present invention is to provide a liquid crystal panel mounting structure and a liquid crystal panel mounting method which realizes compact and highly reliable liquid crystal panel mounting at low cost.

[0019]

In order to achieve the above object, the invention according to claim 1 is characterized in that a liquid crystal is sandwiched between two substrates provided with facing alignment films formed on their surfaces. In the mounting structure of a liquid crystal panel, the connection terminals arranged on the peripheral portion of the liquid crystal panel and the connection terminals provided on the circuit board are connected through a resin connecting material. It is characterized in that a layer of an alignment film material forming the alignment film is formed at least at the interface between the liquid crystal panel side edge of the resin connecting material between the terminals and the liquid crystal panel substrate.

Further, the invention according to claim 2 is characterized in that, in the mounting structure of the liquid crystal panel according to claim 1, the resin connecting material between the both connection terminals is an anisotropic conductive film. There is.

Further, the invention according to claim 3 is characterized in that, in the mounting structure of the liquid crystal panel of the invention according to claim 1, the resin-made connecting material existing between the both connection terminals is a photocurable resin. There is.

The invention according to claim 4 is characterized in that, in the mounting structure of the liquid crystal panel according to claim 1, the resin-made connecting material between the both connection terminals is a thermosetting resin. There is.

According to a fifth aspect of the present invention, in the mounting structure of the liquid crystal panel according to any one of the first to fourth aspects, the resin connection material in the layer of the alignment film material is used. The joint surface is characterized by being roughened.

According to a sixth aspect of the present invention, in the liquid crystal panel mounting structure according to any one of the first to fifth aspects of the present invention, the resin connection material existing between the both connection terminals is the above-mentioned. A layer of the alignment film material is formed at the interface between the edge portion on the circuit board side and the substrate of the liquid crystal panel.

According to a seventh aspect of the present invention, in the mounting structure of the liquid crystal panel according to any one of the first to sixth aspects, a sealing material for sealing two substrates in the liquid crystal panel is used. And a layer of the alignment film material is formed on at least a part of the boundary between the substrate and each of the substrates, and the joint surface of the layer of the alignment film material with the sealing material is roughened. There is.

The invention according to claim 8 is a method of manufacturing a liquid crystal panel for realizing the mounting structure of the liquid crystal panel according to any one of claims 5 to 7.
A step of forming an alignment film on the substrate of the liquid crystal panel, a step of irradiating the alignment film at a portion of the formed alignment film to be sealed with the sealing material later, and the alignment film are formed. It is characterized by including a step of forming a liquid crystal panel by a predetermined procedure using the substrate.

Further, the invention according to claim 9 is the method for manufacturing a liquid crystal panel according to claim 8, wherein the step of irradiating the formed alignment film with light is performed at a portion which is later sealed with the sealing material. The process is the same as the process of irradiating the alignment film on the inner side, which is the alignment film for initial alignment of the liquid crystal, with light.

[0028]

According to the first to fourth aspects of the invention, the connection terminals provided on the peripheral portion of the liquid crystal panel and the connection terminals provided on the circuit board are connected via the resin connection material.
At that time, in the middle of the thermal expansion coefficient of the resin-made connecting material formed at the interface between the liquid crystal panel-side substrate and at least the liquid crystal panel-side edge of the resin-made connecting material and the thermal expansion coefficient of the substrate. The adhesive force between the substrate and the resin-made connecting material is enhanced by the stress relaxation effect in the surface direction of the substrate by the layer of the alignment film material having a thermal expansion coefficient.

Further, in the invention according to claim 5, the joint surface of the alignment film material layer formed on the liquid crystal panel with the resin connecting material is roughened. Therefore, when the liquid crystal panel is connected to the circuit board via the resin-made connecting material, the adhesion between the layer of the alignment film material and the resin-made connecting material increases.

Further, in the invention according to claim 6, the interface between the edge portion on the side of the circuit board and the substrate of the liquid crystal panel in the resin-made connecting material for connecting the connection terminal of the liquid crystal panel and the connection terminal of the circuit board. The layer of the alignment film material formed on the substrate further enhances the adhesion between the substrate and the resin connecting material.

Further, in the invention according to claim 7, in the layer of the alignment film material formed on at least a part of the boundary between the respective substrates and the sealing material for sealing the two substrates in the liquid crystal panel. The joint surface with the sealing material is roughened. Therefore, the adhesion between the alignment film material and the sealing material is enhanced, and the layer of the alignment film material can be formed in contact with the sealing material.

[0032]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 is a sectional view of a connecting portion around the liquid crystal panel in the liquid crystal panel mounting structure of this embodiment. Since the respective members in this sectional view are exactly the same as those in FIG. 13, the same reference numerals are given and the description thereof will be omitted.

In the present embodiment, the anisotropic conductive film 1 is the outer peripheral portion of the insulating film 20 which covers the lead wiring 19 on the liquid crystal panel side and forms the contour of the panel side terminal 18.
The alignment film material 25 is formed in a strip shape at a position where the tip of the output-side lead wiring 14 is located in the flexible substrate 8 when the flexible substrate 8 is connected via 7. Therefore, the lead wiring 14 on the flexible substrate 8 side is connected to the panel side terminal 18 on the liquid crystal panel side through the anisotropic conductive film 17.
When the connection is made, the side edge of the anisotropic conductive film 17 on the liquid crystal panel side just rides on the alignment film material 25. At that time, the alignment film material 25 can be easily formed by only changing the coating surface of the alignment film 11 when forming the alignment film 11.

Here, the alignment film material 25 is 1.5 to 6 ×.
It has a thermal expansion coefficient of about 10 ⁻⁵ / ° C. and exhibits an intermediate value between the thermal expansion coefficient of the substrate 3 and the thermal expansion coefficient of the anisotropic conductive film 17. Furthermore, since the orientation film material 25 has a low hardness, it has a stress relaxation effect in the surface direction of the substrate 3. Therefore, by interposing the alignment film material 25 between the anisotropic conductive film 17 and the substrate 3, the adhesive force between the surface of the substrate 3 and the anisotropic conductive film 17 is increased and the interface C of the anisotropic conductive film 17 is increased. It can prevent peeling. That is, according to this embodiment, the anisotropic conductive film 1 is formed.
Invasion of gas, moisture, etc. from the interface C at 7 can be sufficiently prevented, and high reliability can be obtained.

Further, according to this embodiment, as described above,
Since the adhesion between the substrate 3 and the anisotropic conductive film 17 is increased, it is not necessary to cover the periphery of the connection portion with the protective resin as shown in FIG. 13, and the cost can be reduced. Further, the above-described effects can be easily achieved by using the conventional materials and processes as they are if the currently mainstream anisotropic conductive film 17, the photo-curing resin, or the thermosetting resin is used as the connecting material. The increase in cost associated with the formation of the is negligible.

FIG. 2 is an enlarged plan view of the periphery of the connection portion in FIG. As described above, in this embodiment, the side edge 17 ′ of the anisotropic conductive film 17 on the liquid crystal panel side is the alignment film material 25.
Is on top. Therefore, the resin component of the anisotropic conductive film 17 exuded on the alignment film material 25 easily flows, and as a result, the dispersity of the conductive particles 21 increases. Therefore, in the anisotropic conductive film 17 that has flowed out onto the alignment film material 25, the conductive particles 21 are scattered more uniformly than in the conventional case. That is, according to the present embodiment, the insulation reliability of the lead wiring 14 is high and it is possible to sufficiently cope with a minute connection pitch.

Further, in the embodiment shown in FIG. 3, the surface of the alignment film material 26 is roughened by etching, light irradiation or the like. By roughening the surface of the alignment film material 26 in this way, the adhesion between the connection material such as the anisotropic conductive film 17 and the alignment film material 26 is increased. Further, if the anisotropic conductive film 17 is heated and melted at the time of connection, the fluidity of the resin component is further improved, the excess resin component flows out, the area is expanded, and the conductive particles 21 are not provided between the lead wires 14 and 14. Will also be dispersed. Therefore, the insulation resistance between the adjacent lead wires 14 increases. Thus, in this embodiment, the substrate 3
Thus, high adhesion with the anisotropic conductive film 17 and high insulation reliability of the lead wiring 14 can be obtained.

In the embodiment shown in FIG. 4, in addition to the structure shown in FIG. 1, an alignment film material 27 is formed also on the edge of the connecting portion of the substrate 3 of the liquid crystal panel on the flexible substrate 8 side. By doing so, when the liquid crystal panel and the flexible substrate 8 are connected via the anisotropic conductive film 17, the anisotropic conductive film 17 is formed.
In addition to the edge portion on the liquid crystal panel side (inner side) in the above, the edge portion on the flexible substrate 8 side (outer side) is connected to the substrate 3 via the alignment film material 27. Therefore, it is possible to prevent peeling of the edge side of the substrate 3 and prevent invasion of gas, moisture, and the like from the edge side of the substrate 3, and further higher adhesion and reliability can be obtained.

In the embodiment shown in FIG. 5, in addition to the structure shown in FIG. 1, an alignment film material 25 formed at the position where the tip of the lead wiring 14 on the output side is located when the flexible substrate 8 is connected. The alignment film material 28 is also formed on the inside. By doing so, the portion of the lead wiring 19 on the liquid crystal panel side outside the image display region 2 is doubly protected by the insulating film 20 and the alignment film material 28, and the reliability is further improved.

In the embodiment shown in FIG. 6, in addition to the configuration shown in FIG. 1, the liquid crystal panel portion is constructed as follows. That is, the alignment films 11 and 12 formed on the substrates 3 and 4 of the liquid crystal panel are further spread outward. Then, when the substrates 3 and 4 are laminated with the orientation films 11 and 12 facing each other and the periphery is sealed with the sealing material 5, the upper and lower ends of the inner wall of the sealing material 5 hang on the orientation films 11 and 12 later. To do so. Then, the regions 29 and 3 of the alignment films 11 and 12 which hang on the sealing material 5
The surface of 0 is roughened by etching or light irradiation. By doing so, the adhesion between the regions 29 and 30 of the alignment films 11 and 12 and the seal material 5 is improved, and the alignment film layers 11 and 12 and the seal material 5 are not separated from each other as in the case where adhesion reliability cannot be obtained. Therefore, it is not necessary to provide a separating portion in consideration of printing and application accuracy. Therefore, according to this embodiment, it is possible to reduce the size of the liquid crystal panel only by the above-mentioned separated portion which is conventionally required.

The embodiment shown in FIG. 7 has a configuration in which FIGS. 1, 5 and 6 are combined. That is, the alignment film 31 formed on the substrate 3 of the liquid crystal panel projects outward from the image display region 2 and extends to the region of the alignment film material 25 shown in FIG. The alignment film 33 formed on the substrate 4 extends to the outer edge of the substrate 4. Then, the regions 32 and 3 of the alignment films 31 and 33 that come into contact with the sealing material 5
The surface of No. 4 is roughened by etching or light irradiation.

By doing so, it is possible to prevent gas, moisture, etc. from entering from the interface C in the anisotropic conductive film 17 without covering the periphery of the connection portion with the protective resin, and to extend the wiring 19 outside the image display area 2. That is, it is possible to double protect the portion of the liquid crystal panel, improve the adhesion between the alignment films 31 and 33 and the sealing material 5, and reduce the size of the liquid crystal panel. Further, at that time, the alignment films 11 and 25 of FIG.
The alignment film 28 of FIG. 5 and the alignment film 30 of FIG. 6 can be formed in one step. Therefore, the steps for forming each alignment film are not required, and the cost increase can be suppressed. That is, according to the present embodiment, a highly reliable and compact size liquid crystal display device can be provided at low cost.

The embodiment shown in FIGS. 8 and 9 is an example of application development of the above embodiment. In the embodiment shown in FIG. 8, in addition to the configuration shown in FIG. 7, the alignment film material 27 is formed also on the outer peripheral edge of the connection portion in the substrate 3 of the liquid crystal panel as in the embodiment shown in FIG. Then, a region from the flexible substrate 8 to the substrate 4 on the upper side of the periphery of the connection portion by the anisotropic conductive film 17 and a region from the flexible substrate 8 to the substrate 3 on the lower side of the periphery of the connection portion are used to protect silicon or epoxy resin. It is covered with the resins 35 and 36. In the case of the present embodiment, since the upper and lower portions of the periphery of the connection portion are covered with the protective resins 35, 35, cost reduction cannot be expected. However, the connection reliability can be greatly improved as compared with the above-mentioned respective embodiments, and it can be widely used from the level of consumer parts to the level of vehicle-mounted parts.

The embodiment shown in FIG. 9 is different from the embodiment shown in FIG. 7 in that the LSI 7 for driving the liquid crystal display device 1 is directly mounted on the substrate 3 of the liquid crystal panel without a flexible substrate. This is an example of the on-glass type. The LSI 7 is connected to the panel side terminal 18 on the liquid crystal panel side through the anisotropic conductive film 37. At this time, the inner edge portion of the anisotropic conductive film 37 is connected to the substrate 3 via the alignment film 31, while the outer edge portion is connected to the substrate 3 via the alignment film material 27. . Therefore, according to the present embodiment, a highly reliable and compact size COG is provided.
The liquid crystal display device of the type can be provided at low cost.

A method of manufacturing a liquid crystal panel for realizing the mounting structure of the liquid crystal panel in each of the above embodiments will be described below.

FIG. 10 is an explanatory diagram of a liquid crystal panel manufacturing method for realizing the liquid crystal panel mounting structure shown in FIG. In FIG. 10, on the glass substrate 3 of the liquid crystal panel,
The base film layer 9 is formed of Ta ₂ O ₅ , SiO ₂ or the like, the routing wiring 19 is formed of a thin film of Ta, Ti, Al, Cu, Mo or the like, and the insulating film 20 is further formed of SiO ₂ , Ta ₂ O ₅ Etc., and after forming a film such as a color filter, the alignment film 11 is finally formed from polyimide or the like. At that time, the insulating film 20 and the alignment film 11 are outside the image display region 2 and reach the position where the tip of the lead wire 14 on the output side of the flexible substrate 8 reaches when the flexible substrate 8 is connected. It is formed. Then, the region of the alignment film 11 that is later sealed with the sealing material 5 is removed. As a method of forming the alignment film 11 as described above, the image display region 2 and the outside of the image display region 2 are excluded except the region on the insulating film 20 to be subsequently sealed with the shield material 5. A method of forming patterns at the same time may be adopted.

Then, the alignment film 11 is irradiated with ultraviolet rays 39 through a mask 38 that allows light to pass through a special pattern (for example, a pattern having a minute pattern of the number of picture elements in the image display area 2 or several times thereof), and post-treatment is performed. When applying
At the same time, the ultraviolet ray 39 is also applied to the region 26 of the alignment film 11 outside the image display region 2. In this way, the surface of the alignment film 11 is roughened by irradiating the region 26 with light, and the alignment film 26 for mounting as described in FIG. 3 is formed.

Thereafter, the alignment film 1 is formed by the same procedure as described above.
The glass substrate 4 on which the film 2 is formed and the alignment film 26 for mounting described above.
The liquid crystal panel is formed by making the orientation films 11 and 12 face the glass substrate 3 on which the film has been formed and sealing the periphery with the sealing material 5. An anisotropic conductive film is formed between the panel side terminal 18 which is the tip of the lead wiring 19 formed on the glass substrate 4 and the lead wiring 14 on the output side of the flexible substrate 8 on which the LSI 7 for driving the liquid crystal display device is mounted. It is connected by thermocompression bonding via 17.

The connection structure between the liquid crystal panel and the flexible substrate 8 in the liquid crystal display device thus mounted is shown in FIG.
As shown in FIG. 6, the alignment film 25 is interposed between the inner edge of the anisotropic conductive film 17 and the substrate 3, and the interface C of the anisotropic conductive film 17 does not peel off, and gas, moisture, etc. Intrusion is prevented. Further, as described above, the irradiation of the mounting alignment film 26 with the ultraviolet rays is performed simultaneously with the irradiation of the ultraviolet rays 39 with respect to the alignment films 11 and 12 for liquid crystal alignment formed on the glass substrates 3 and 4. Therefore,
A high-reliability liquid crystal panel connection structure can be realized without increasing the cost without requiring a roughening process dedicated to the alignment film material 26. The alignment film 2 for mounting at that time
Even if the ultraviolet ray irradiation side in 6 is the back surface side (the glass substrate 3 side) of the alignment film 26, the surface of the alignment film 26 is roughened because the density and the like of the alignment film 26 are internally modified.

FIG. 11 is an explanatory view of another liquid crystal panel manufacturing method for realizing the liquid crystal panel mounting structure shown in FIG. In FIG. 11, as described above, the alignment films 11 and 26 are formed on the glass substrate 3 of the liquid crystal panel, and the alignment film 12 is formed on the glass substrate 4. Then, the glass substrate 4 and the glass substrate 3 are connected to each other by the alignment films 11 and 1.
The two are opposed to each other and the periphery thereof is sealed with an ultraviolet curable sealing material 5 to form a liquid crystal panel. After that, the sealing material 5 is irradiated with the ultraviolet ray 41 through the mask 40 and the sealing material 5
Cure. In this embodiment, the ultraviolet ray passing port 40 ′ of the mask 40 at that time is punched so that the mounting alignment film 26 on the glass substrate 3 is also irradiated with the ultraviolet ray 41. By doing so, when the sealing material 5 is irradiated with the ultraviolet rays 41, the mounting alignment film 26 is also irradiated with the ultraviolet rays 41, and the surface of the alignment film 26 is roughened.

The liquid crystal panel thus obtained is mounted in the same manner as in the embodiment according to FIG. Then, as shown in FIG. 3, the inner edge of the anisotropic conductive film 17 and the substrate 3
Thus, the connection structure between the liquid crystal panel and the flexible substrate 8 is obtained in which the alignment film 25 is interposed between and, and the interface C of the anisotropic conductive film 17 is not separated. Incidentally, also in the present embodiment, since the irradiation of the mounting alignment film material 26 with ultraviolet rays is carried out by utilizing the usual curing step of the sealing material 5,
A highly reliable liquid crystal panel connection structure can be realized without increasing costs.

The method of irradiating the alignment film for mounting shown in FIGS. 10 and 11 with ultraviolet rays is applicable not only to the liquid crystal panel shown in FIG. 3 but also to the liquid crystal panels shown in FIGS. 6 to 9. Needless to say. Further, although the connecting material in each of the above embodiments is the anisotropic conductive film 17, it may be a photocurable resin or a thermosetting resin.

[0054]

As is clear from the above, the liquid crystal panel mounting structure of the inventions according to claims 1, 3 and 4 is made of resin for connecting the connection terminals of the liquid crystal panel and the connection terminals of the circuit board. A layer of an alignment film material forming an alignment film of the liquid crystal panel is formed at an interface between at least an edge portion of the connection material on the liquid crystal panel side and a substrate of the liquid crystal panel. Therefore, the resin-made connecting material and the substrate will be bonded through the layer of the orientation film material having a low coefficient of thermal expansion and an intermediate coefficient of thermal expansion between the two,
A high adhesion can be obtained by absorbing the thermal stress caused by heating when connecting the liquid crystal panel and the circuit board.
Further, since the adhesive force between the resin-made connecting material and the substrate of the liquid crystal panel is increased, a protective resin for protecting the periphery of the connecting portion is not required, and the cost can be reduced.
That is, according to these inventions, highly reliable liquid crystal panel mounting can be realized at low cost.

Further, in the liquid crystal panel mounting structure of the invention according to claim 2, the edge portion on the liquid crystal panel side in the anisotropic conductive film connecting the connection terminal of the liquid crystal panel and the connection terminal of the circuit board is the alignment film. Since it is on the material layer, the resin component of the anisotropic conductive film easily flows out when the liquid crystal panel and the circuit board are connected, and the dispersity of the conductive particles increases. Therefore, according to the present invention, the insulation reliability between the adjacent connection terminals on the circuit board is enhanced, and a more reliable liquid crystal panel mounting structure can be obtained.

In the liquid crystal panel mounting structure according to the fifth aspect of the present invention, the joint surface of the alignment film material layer with the resin connecting material is roughened prior to mounting.
The adhesion between the layer of the alignment film material and the resin connecting material is increased, and the fluidity of the resin connecting material is improved. Therefore, when the resin-made connecting material is an anisotropic conductive film, the degree of dispersion of the conductive particles is further increased, and the insulation reliability between the adjacent connection terminals on the circuit board is further improved.

According to a sixth aspect of the present invention, there is provided a liquid crystal panel mounting structure, wherein the circuit board side edge of a resin connecting material for connecting the liquid crystal panel connecting terminal and the circuit board connecting terminal to the liquid crystal panel. Since the layer of the alignment film material is formed at the interface with the substrate of the panel, the adhesive force between the resin connecting material and the substrate of the liquid crystal panel can be further enhanced.

According to a seventh aspect of the present invention, there is provided a liquid crystal panel mounting structure, wherein the alignment film material is provided on at least a part of a boundary between each substrate and a sealing material for sealing two substrates in the liquid crystal panel. Layer is formed and the joint surface of the layer of the alignment film material with the sealing material is roughened prior to mounting, so that the adhesive force between the substrate and the sealing material is increased. Therefore, according to the present invention, in addition to the resin-made connecting material and the substrate exhibiting high adhesion, the alignment film formed in the image display region on the substrate of the liquid crystal panel is brought into contact with the sealing material. Can be formed. Therefore, according to the present invention, it is not necessary to provide a space between the alignment film and the sealing material in the image display region, and a compact liquid crystal panel mounting structure can be provided.

According to the eighth aspect of the present invention, there is provided a method of manufacturing a liquid crystal panel, which comprises a step of forming an alignment film on a substrate of the liquid crystal panel, and a sealing material for sealing after at least one of the formed alignment films. Since there is a step of irradiating the alignment film at the position to be stopped with light and a step of forming a liquid crystal panel by a predetermined procedure using the substrate on which the alignment film is formed, a seal for sealing the two substrates is provided. It is possible to form a liquid crystal panel in which the bonding surface of the alignment film formed on the boundary between the material and each substrate is roughened. Therefore,
According to the present invention, the resin-made connecting material and the substrate exhibit high adhesion, and the alignment film formed in the image display region is formed in contact with the sealing material to be compact and highly reliable. Structure of a flexible liquid crystal panel can be easily realized.

In the method for manufacturing a liquid crystal panel according to the ninth aspect of the present invention, in the step of irradiating the formed alignment film with light, the alignment film inside the portion to be sealed later with the sealing material is used. Since it is the same step as the step of irradiating the alignment film for the initial alignment of the liquid crystal with light, it is necessary to specially provide a step of irradiating the alignment film at a location to be sealed with the sealing material later with light to roughen the surface. Absent. Therefore, there is no need to make capital investment for that process, and there is no increase in man-hours for that process.
Therefore, according to the present invention, it is possible to form a compact liquid crystal panel at a low cost, which can easily realize a highly reliable liquid crystal panel mounting structure.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a connection portion in an example of a liquid crystal panel mounting structure of the present invention.

FIG. 2 is an enlarged plan view of a connecting portion in FIG.

FIG. 3 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from that of FIG.

FIG. 4 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from FIGS. 1 and 3.

FIG. 5 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from FIGS. 1, 3 and 4.

FIG. 6 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from FIGS. 1 and 3 to 5;

FIG. 7 is a cross-sectional view of a connecting portion in a liquid crystal panel mounting structure different from FIGS. 1 and 3 to 6;

FIG. 8 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from FIGS. 1 and 3 to 7.

FIG. 9 is a cross-sectional view of a connection portion in a liquid crystal panel mounting structure different from FIGS. 1 and 3 to 8;

FIG. 10 is an explanatory view of a method for manufacturing a liquid crystal panel of the present invention.

FIG. 11 is an explanatory diagram of a method of manufacturing a liquid crystal panel different from that in FIG.

FIG. 12 is a plan view of a conventional liquid crystal panel mounting structure.

13 is a cross-sectional view taken along the line AA in FIG.

FIG. 14 is an enlarged plan view of a connecting portion in FIG.

[Explanation of symbols]

1 ... Liquid crystal display device, 2 ... Image display area, 3, 4 ... Substrate, 5 ... Sealing material, 6 ... Liquid crystal, 7 ... LSI,
8 ... Flexible substrate, 11, 12, 29, 3
0 to 34 ... Alignment film, 13, 14 ... Lead wiring,
17, 37 ... An anisotropic conductive film, 18 ... Panel side terminal,
19 ... Routing wiring, 25, 26 ... Alignment film material, 35, 36 ... Protective resin, 38, 40
…mask.

Claims (9)

[Claims] 1. A connection terminal provided on a peripheral portion of a liquid crystal panel formed by sandwiching a liquid crystal between two substrates provided with facing alignment films facing each other, and a connection terminal provided on a circuit board. And a liquid crystal panel mounting structure in which the connection terminal is connected via a resin connecting material, and the liquid crystal panel-side edge portion of the resin connecting material between the both connecting terminals and the liquid crystal. A mounting structure of a liquid crystal panel, wherein a layer of an alignment film material forming the alignment film is formed on an interface of the panel with a substrate. 2. The liquid crystal panel mounting structure according to claim 1, wherein the resin connecting material between the connection terminals is an anisotropic conductive film. 3. The liquid crystal panel mounting structure according to claim 1, wherein the resin-made connecting material between the connection terminals is a photocurable resin. 4. The liquid crystal panel mounting structure according to claim 1, wherein the resin connecting material between the connecting terminals is a thermosetting resin. 5. The liquid crystal panel mounting structure according to claim 1, wherein a joint surface of the alignment film material layer with the resin connecting material is roughened. A liquid crystal panel mounting structure characterized by the above. 6. The liquid crystal panel mounting structure according to claim 1, wherein an edge portion of the resin connecting material between the connecting terminals on the side of the circuit board and the liquid crystal. A mounting structure of a liquid crystal panel, wherein a layer of the alignment film material is formed at an interface between the panel and a substrate. 7. The liquid crystal panel mounting structure according to claim 1, wherein at least a boundary between each of the substrates and a sealing material that seals two substrates in the liquid crystal panel. A mounting structure of a liquid crystal panel, wherein a layer of the alignment film material is formed in a part, and a joint surface of the alignment film material layer with the sealing material is roughened. 8. A method of manufacturing a liquid crystal panel for realizing the liquid crystal panel mounting structure according to claim 5, wherein an alignment film is formed on a substrate of the liquid crystal panel. A step of irradiating the alignment film of the formed alignment film, which is to be subsequently sealed with the sealing material, with light, and a liquid crystal according to a predetermined procedure using the substrate on which the alignment film is formed. A method of manufacturing a liquid crystal panel, comprising a step of forming a panel. 9. The method for manufacturing a liquid crystal panel according to claim 8, wherein the step of irradiating the formed alignment film with light is performed on the alignment film inside a portion to be sealed with the sealing material later. A method of manufacturing a liquid crystal panel, which is the same as the step of irradiating an alignment film for initial alignment of liquid crystal with light.