JP3769995B2 - Manufacturing method of liquid crystal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of manufacturing a liquid crystal device that displays images such as letters, numbers, and patterns by controlling the orientation of liquid crystal sealed between a pair of substrates.
[0002]
[Prior art]
In general, a liquid crystal device is formed by attaching an auxiliary device such as an illumination device such as a backlight or a liquid crystal driving IC to a liquid crystal panel having a structure in which liquid crystal is sealed between a pair of substrates. A liquid crystal panel generally includes a first substrate on which a first electrode is formed and a second substrate on which a second electrode is formed bonded to each other with a sealing material, and a gap formed between the substrates, a so-called cell. It is formed by enclosing liquid crystal in the gap.
[0003]
As a method of manufacturing the above liquid crystal device, conventionally, a first substrate base material on which a plurality of first electrodes for a plurality of liquid crystal panels are formed and a second substrate base material on which second electrodes for a plurality of liquid crystal panels are formed are mutually connected. A large-sized panel structure including a plurality of liquid crystal panel parts is formed in combination, and then the large-sized panel structure is cut to form a medium-sized panel structure in which the liquid crystal inlets of the plurality of liquid crystal panel parts are exposed to the outside. Next, liquid crystal is injected into each liquid crystal panel portion through the exposed liquid crystal injection port, and then the medium format panel structure is divided into individual liquid crystal panels, and then the divided individual liquid crystal panels A manufacturing method comprising a series of steps of attaching a polarizing plate to a substrate is known.
[0004]
[Problems to be solved by the invention]
However, in the above conventional method for manufacturing a liquid crystal device, since the medium-sized panel structure is divided into individual liquid crystal panels and polarizing plates are pasted on the individual liquid crystal panels, the polarizing plate pasting process is troublesome. There was a problem that it took time.
[0005]
The present invention has been made in view of the above-described problems, and can improve the polarizing plate attaching process in the method for manufacturing a liquid crystal device, thereby making it possible to easily and quickly manufacture the liquid crystal device. For the purpose.
[0006]
[Means for Solving the Problems]
(1) In order to achieve the above object, a method for manufacturing a liquid crystal device according to the present invention includes a first substrate base material on which a plurality of first electrodes for a plurality of liquid crystal panels are formed and a second electrode for a plurality of liquid crystal panels. A substrate assembly step for forming a large panel structure including a plurality of liquid crystal panel portions by bonding the second substrate base materials to each other, and cutting the large panel structure to provide a plurality of the liquid crystal panel portions. Forming a strip-shaped medium format panel structure, a substrate overhanging portion including an IC mounting area of each liquid crystal panel portion being continuous in the longitudinal direction of the medium format panel structure, and a liquid crystal injection port of each liquid crystal panel portion A first breaking step of exposing the liquid crystal layer to the inside surface of each liquid crystal panel through the exposed liquid crystal injection port, and a substrate overhanging portion. An IC mounting process for mounting an IC chip on the medium panel, and after performing the liquid crystal injection process and the IC mounting process on the medium format panel structure, the medium format polarizing plate having a size corresponding to at least a plurality of the liquid crystal panel portions is A polarizing plate pasting step for pasting the medium format panel structure, and a second breaking step for dividing the medium format panel structure with the medium format polarizing plate pasted into individual liquid crystal panels after the polarizing plate pasting step. It is characterized by that.
[0007]
According to this method for manufacturing a liquid crystal device, after the liquid crystal panels are individually divided, the polarizing plates are not attached to the individual liquid crystal panels one by one. Since the size polarizing plate is attached to the medium format panel structure, the step of attaching the polarizing plate is remarkably simplified, and thus the liquid crystal device can be manufactured easily and quickly.
Further, the mounting process of the IC chip when manufacturing a so-called COG (Chip On Glass) type liquid crystal device having a structure in which the IC chip is directly mounted on the substrate overhanging portion is remarkably simplified. The device can be manufactured easily and quickly.
[0013]
(2) Regarding the cutting of the panel structure, a cutting method is widely known in which a groove called a scribe groove is formed in a substrate such as glass or plastic, and the substrate is divided by force with reference to the scribe groove. However, instead of this cutting method, the panel structure can be cut using a laser beam.
[0014]
According to the cutting method using the laser beam, when the structure (2) in which both the polarizing plate and the substrate are cut is adopted, both of them can be cut accurately without any trouble.
[0015]
By the way, when cutting using a scribe groove, a minute crack called a microcrack is generated on the cut surface of the liquid crystal panel formed by the cutting, and the crack is generated in the liquid crystal panel based on the microcrack. There is a risk.
[0016]
On the other hand, if the substrate of the liquid crystal panel is cut using a laser beam, the cut surface of the substrate becomes remarkably smooth as compared with the case where the scribing method is used, and microcracks are not generated. Therefore, damage to the liquid crystal panel can be prevented beforehand.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Before describing a method for manufacturing a liquid crystal device according to the present invention, first, a liquid crystal device manufactured using the method will be described. FIG. 1 shows an embodiment of the liquid crystal device. The liquid crystal device 1 is formed by mounting a liquid crystal driving IC 3 as an IC chip on a liquid crystal panel 2. In addition, an illumination device such as a backlight, a light reflection plate, and the like are provided on one surface of the liquid crystal panel 2 as necessary.
[0018]
The liquid crystal panel 2 has a pair of substrates 4 a and 4 b facing each other, and these substrates are bonded to each other by a sealing material 7. These substrates 4a and 4b are formed by forming electrodes and other necessary elements on a substrate material formed of a hard light-transmitting material such as glass, or a light-transmitting material having flexibility such as plastic. Produced.
[0019]
In FIG. 2, a first electrode 9a acting as a common electrode, for example, is formed in a predetermined pattern on the liquid crystal side surface of the substrate material 8a of the first substrate 4a, that is, the surface facing the second substrate 4b. An overcoat layer 11a is formed, and an alignment film 12a is further formed thereon. A polarizing plate 6a is attached to the outer surface of the substrate material 8a.
[0020]
On the liquid crystal side surface of the substrate material 8b of the second substrate 4b facing the first substrate 4a, that is, the surface facing the first substrate 4a, for example, a second electrode 9b acting as a segment electrode is formed in a predetermined pattern, An overcoat layer 11b is formed thereon, and an alignment film 12b is further formed thereon. A polarizing plate 6b is attached to the outer surface of the substrate material 8b.
[0021]
The first electrode 9a and the second electrode 9b are formed to a thickness of about 1000 angstroms by a transparent electrode such as ITO (Indium Tin Oxide), for example, and the overcoat layers 11a and 11b are made of, for example, silicon oxide, titanium oxide, or their The alignment film 12a and 12b are formed to a thickness of about 800 Å by a polyimide resin, for example.
[0022]
As shown in FIG. 1, the first electrode 9a is formed in a so-called stripe shape by arranging a plurality of linear patterns in parallel with each other, while the second electrode 9b intersects the first electrode 9a. By arranging a plurality of linear patterns in parallel with each other, they are also formed in stripes. A plurality of points where these electrodes 9a and 9b intersect in a dot matrix form a pixel for displaying an image. An area partitioned by the plurality of pixels is a display area for displaying an image such as a character.
[0023]
As shown in FIG. 2, a plurality of spacers 13 are dispersed on one liquid crystal side surface of the first substrate 4a and the second substrate 4b formed as described above. A sealing material 7 is provided in a frame shape as shown in FIG. As shown in FIG. 2, a conductive material 16 is dispersed inside the seal material 7. Further, as shown in FIG. 1, a liquid crystal injection port 7a is formed in a part of the sealing material 7.
[0024]
A uniform dimension held by the spacer 13, for example, a gap of about 5 μm, that is, a so-called cell gap is formed between the substrates 4a and 4b, and the liquid crystal 14 is injected into the cell gap through the liquid crystal injection port 7a. After completion of the above, the liquid crystal inlet 7a is sealed with resin or the like.
[0025]
In FIG. 1, the first substrate 4a has a substrate overhanging portion 4c that protrudes outside the second substrate 4b, and the first electrode 9a on the first substrate 4a directly extends to the substrate overhanging portion 4c to form a wiring pattern. It is 15. Further, the second electrode 9b on the second substrate 4b is connected to the wiring pattern 15 on the substrate overhanging portion 4c through the conductive material 16 (see FIG. 2) dispersed inside the sealing material 7. Reference numeral 20 denotes an external connection terminal for electrical connection with an external circuit (not shown).
[0026]
A large number of the electrodes 9a and 9b, the wiring pattern 15 extending from them, and the external connection terminals 20 are actually formed over the entire surface of the respective substrates 4a and 4b at a very narrow interval. In each figure, in order to show the structure in an easy-to-understand manner, those electrodes and the like are schematically shown at intervals wider than the actual intervals, and some of the electrodes are not shown. Further, the electrodes 9a and 9b formed in the region where the liquid crystal is sealed are not limited to being formed in a straight line, but may be formed in an appropriate pattern.
[0027]
In FIG. 1, bumps 21 as IC side terminals are formed on the active surface 3 a of the liquid crystal driving IC 3. In the present embodiment, a so-called COG (Chip On Glass) type liquid crystal device having a structure in which the liquid crystal driving IC 3 is directly mounted on the substrate extension 4c of the liquid crystal panel 2 will be considered. When mounting the liquid crystal driving IC 3 on the substrate overhanging portion 4c, first, an adhesive material is applied to the IC mounting region J, which is a region where the liquid crystal driving IC 3 is to be mounted and has an area substantially the same as the IC 3 ACF (Anisotropic Conductive Film) 17 is attached, and then the active surface 3a of the liquid crystal driving IC 3 is attached to the ACF 17, whereby the liquid crystal driving IC 3 is temporarily attached to the IC mounting region J. .
[0028]
As is well known, the ACF 17 is a conductive polymer film that is used to electrically connect together a pair of terminals with anisotropy. For example, as shown in FIG. Alternatively, it is formed by dispersing a large number of conductive particles 19 in a thermosetting resin film 22.
[0029]
The substrate overhanging portion 4c and the liquid crystal driving IC 3 are thermocompression bonded with the ACF 17 interposed therebetween, that is, by applying pressure under heating, the liquid crystal driving IC 3 is adhered to the substrate overhanging portion 4c, and the bump 21 of the liquid crystal driving IC 3 A connection having conductivity in one direction is realized between the wiring pattern 15 on the substrate extension portion 4c and between the bump 21 of the liquid crystal driving IC 3 and the external connection terminal 20 on the substrate extension portion 4c.
[0030]
With respect to the liquid crystal device 1 configured as described above, a scanning voltage is applied to each of the first electrode 9a and the second electrode 9b for each row by the liquid crystal driving IC 3 and further to the other of the electrodes. By applying a data voltage based on the display image for each pixel, light modulation that passes through each pixel portion selected by the application of both voltages is performed, so that an image such as a character, a number, or the like is formed outside the substrate 4a or 4b. Is displayed.
[0031]
Hereinafter, a manufacturing method for manufacturing the liquid crystal device 1 having the above-described configuration will be described with reference to a process diagram shown in FIG.
[0032]
First, as shown in FIG. 4, each liquid crystal panel substrate portion 4a of a large first substrate base material 18a having a size corresponding to a plurality of first substrates 4a constituting the liquid crystal panel 2 is formed on the liquid crystal panel substrate portion 4a shown in FIG. As shown in FIG. 3, the first electrode 9a, the wiring pattern 15 and the external connection terminal 20 are formed by using a well-known pattern forming method such as a photolithography method using ITO as a material (step P1 in FIG. 3). In FIG. 6A, a region where the wiring patterns 15 and the tips of the external connection terminals 20 gather is an IC mounting region J for mounting the liquid crystal driving IC 3 (see FIG. 1).
[0033]
Next, the overcoat layer 11a (see FIG. 2) is formed on the surface of the first substrate base material 18a in FIG. 4 by offset printing using, for example, silicon oxide or titanium oxide (process P2 in FIG. 3). Then, an alignment film 12a (see FIG. 2) is formed by offset printing using, for example, a polyimide resin (process P3 in FIG. 3). Furthermore, the sealing material 7 is formed into a frame shape by screen printing using a material obtained by dispersing a conductive material in an epoxy resin, for example (step P4 in FIG. 3). Thereby, a large first substrate base material 18a as shown in FIG. 4 is formed. In FIG. 4, the overcoat layer and the alignment film are not shown for convenience.
[0034]
On the other hand, as shown in FIG. 5, individual liquid crystal panel substrate portions 4b of a large-sized second substrate base material 18b having a size corresponding to a plurality of second substrates 4b constituting the liquid crystal panel 2 are formed on the liquid crystal panel substrate portions 4b shown in FIG. As shown in FIG. 3, the second electrode 9b is formed by a known pattern forming method, for example, a photolithography method using ITO as a material (step P5 in FIG. 3).
[0035]
Next, the overcoat layer 11b (see FIG. 2) is formed on the surface of the second substrate base material 18b in FIG. 5 by offset printing using, for example, silicon oxide and titanium oxide (step P6 in FIG. 3). Then, for example, an alignment film 12b (see FIG. 2) is formed by offset printing using, for example, a polyimide resin (process P7 in FIG. 3). As a result, a large second substrate base material 18b as shown in FIG. 5 is formed. In FIG. 5, the overcoat layer and the alignment film are not shown for convenience.
[0036]
After the first substrate base material 18a (FIG. 4) and the second substrate base material 18b (FIG. 5) are manufactured as described above, in step P8 of FIG. 3, the first substrate base material 18a and the second substrate base material 18b. The two substrates are bonded to each other by being stacked with the sealing material 7 interposed therebetween, and further pressure-bonding, that is, pressurizing under heating.
[0037]
By this bonding, the tip of the second electrode 9b on the second substrate 4b (see FIG. 6B) and the wiring pattern 15 on the first substrate 4a (see FIG. 6A) are in the sealing material 7. The conductive members 16 (see FIG. 2) dispersed in are electrically connected to each other. In this way, a large panel structure having a size including a plurality of liquid crystal panels 2 is formed. When the first substrate base material 18a and the second substrate base material 18b are bonded together, either the first substrate base material 18a shown in FIG. 4 or the second substrate base material 18b shown in FIG. 5 is shown. It is pasted together with another substrate base material in a state where it is turned upside down.
[0038]
After the large panel structure is manufactured as described above, the first breaking process is performed on the panel structure (process P9 in FIG. 3). Specifically, the substrate base material is cut along the first cutting line L10 shown in FIG. 4 with respect to the first substrate base material 18a constituting the panel structure, while the second substrate base material 18b is shown in FIG. The substrate base material is cut along the first cutting line L11.
[0039]
As a result, as shown in FIG. 7, a plurality of medium format panel structures 2 ′ in which the strip-shaped first substrate base material 18a ′ and the strip-shaped second substrate base material 18b ′ are bonded together are produced. . These medium format panel structures 2 'have a structure in which the liquid crystal injection port 7a of each liquid crystal panel portion included therein is exposed to the outside.
[0040]
In addition, the cutting operation of the panel structure in the process P9 can be performed using, for example, a scribe method, a laser cut method, or the like. In the scribe method, a scribe groove, that is, a cut groove is formed along the cutting line L10 and the cutting line L11, and the panel structure is divided at the cutting lines L10 and L11 by hitting the panel structure from the back side of the scribe groove. It is a method to do.
[0041]
Further, in the laser cutting method, as schematically shown in FIG. 8, a laser beam emitted from the laser emitting device 23, for example, an infrared laser beam R is indicated by an arrow on the first substrate base material 18a or the second substrate base material 18b. This is a method of dividing the substrate base material 18a or 18b from the place where the laser beam R hits by scanning and moving like A.
[0042]
After the medium-sized panel structure 2 ′ (FIG. 7) is manufactured as described above, liquid crystal is injected through the liquid crystal injection port 7a exposed to the outside with respect to a plurality of liquid crystal panel portions included therein, and the injection is completed. Later, the liquid crystal injection port 7a is sealed with resin (step P10 in FIG. 3).
[0043]
After that, the ACF 17 is attached to the IC mounting area J of each liquid crystal panel portion, and the liquid crystal driving IC 3 is further attached on the ACF 17, that is, temporarily attached, and further, the liquid crystal driving is performed by a heated pressure bonding head. By pressing the IC 3, the liquid crystal driving IC 3 is mounted in the IC mounting region J of each liquid crystal panel portion (process P 11 in FIG. 3).
[0044]
Next, medium-sized polarizing plates 6a ′ and 6b ′ having a size capable of covering a plurality of liquid crystal panel portions included in the medium-sized panel structure 2 ′ are respectively replaced with medium-sized first substrate base materials 18a ′ and It sticks on the outer surface of 2nd board | substrate base material 18b '(process P12 of FIG. 3). Thereafter, the second break is performed on the medium-sized panel structure 2 ′ in Step P13.
[0045]
That is, both the first substrate base material 18a ′ and the second substrate base material 18b ′ are cut together with the polarizing plates 6a ′ and 6b ′ along the second cutting line L2 in FIG. The illustrated liquid crystal devices 1 are divided one by one. The second break can also be performed using various cutting methods such as a scribing method, a laser cutting method, etc., but preferably the cutting is performed using the laser cutting method.
[0046]
The first reason why it is desirable to use the laser cutting method is that both the polarizing plates 6a ′ and 6b ′ and the substrates 18a ′ and 18b ′ can be accurately cut without any trouble. The second reason is as follows. That is, when the scribing method is used, a micro crack called a micro crack is generated on the cut surface of the liquid crystal panel substrate, and there is a possibility that the liquid crystal panel may crack based on the micro crack. This is because, when this method is used, the cut surface of the liquid crystal panel substrate becomes remarkably smooth as compared with the case where the scribe method is used, and thus damage to the liquid crystal panel can be prevented.
[0047]
(Other embodiments)
The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications can be made within the scope of the invention described in the claims.
[0050]
【The invention's effect】
According to the method for manufacturing a liquid crystal device of the present invention, after the liquid crystal panels are individually divided, the polarizing plates are not attached to the individual liquid crystal panels one by one, but at least as large as a plurality of liquid crystal panel portions. Since the medium-size polarizing plate is attached to the medium-sized panel structure, the attaching process of the polarizing plate is remarkably simplified, and thus the liquid crystal device can be manufactured easily and quickly.
Further, the mounting process of the IC chip when manufacturing a so-called COG (Chip On Glass) type liquid crystal device having a structure in which the IC chip is directly mounted on the substrate overhanging portion is remarkably simplified. The device can be manufactured easily and quickly.
[Brief description of the drawings]
FIG. 1 is a partially exploded perspective view showing an example of a liquid crystal device manufactured by a method for manufacturing a liquid crystal device according to the present invention.
FIG. 2 is a cross-sectional view of a main part of the liquid crystal device of FIG.
FIG. 3 is a process diagram showing one embodiment of a method for producing a liquid crystal device according to the present invention.
4 is a plan view showing a first substrate base material manufactured through steps P1 to P4 of FIG. 3. FIG.
5 is a plan view showing a second substrate base material manufactured through steps P5 to P7 in FIG. 3; FIG.
6A is a diagram illustrating a portion corresponding to one liquid crystal panel in FIG. 4, and FIG. 6B is a diagram illustrating a portion corresponding to one liquid crystal panel in FIG. 5;
FIG. 7 is a partially exploded perspective view showing an example of a medium format panel structure.
FIG. 8 is a perspective view schematically showing a laser cutting method which is an example of a substrate breaking method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Liquid crystal device 2 Liquid crystal panel 2 'Medium format panel structure 3 Liquid crystal drive IC
3a Active surface 4a 1st board | substrate 4b 2nd board | substrate 4c Substrate overhang | projection part 6a, 6b Polarizing plate 6a ', 6b' Medium format polarizing plate 7 Seal material 7a Liquid crystal inlet 8a 1st board | substrate material 8b 2nd board | substrate material 9a 1st electrode 9b Second electrode 14 Liquid crystal 15 Wiring pattern 18a First substrate base material 18a ′ Medium first substrate base material 18b Second substrate base material 18b ′ Medium format second substrate base material 20 External connection terminal J IC mounting regions L10 and L11 First cutting line L2 Second cutting line R Laser light

Claims (2)

A large-sized panel including a plurality of liquid crystal panel portions by bonding together a first substrate base material on which a plurality of liquid crystal panel first electrodes are formed and a second substrate base material on which a plurality of liquid crystal panel second electrodes are formed. A substrate assembly process for forming the structure;
By cutting the large-sized panel structure, a strip-shaped medium-sized panel structure including a plurality of the liquid crystal panel portions is formed, and a substrate overhang portion including an IC mounting region of each liquid crystal panel portion is formed in the medium-sized panel structure. A first breaking step that is continuous in the longitudinal direction of the panel structure and exposes the liquid crystal injection port of each liquid crystal panel portion to the end surface portion on the opposite side of the substrate extension portion ;
A liquid crystal injection step of injecting a liquid crystal layer into each liquid crystal panel portion through the exposed liquid crystal injection port;
An IC mounting step of mounting an IC chip on the substrate overhanging portion;
After performing the liquid crystal injection step and the IC mounting step on the medium format panel structure, a polarizing plate pasting step for pasting a medium format polarizing plate having a size corresponding to at least a plurality of the liquid crystal panel portions to the medium format panel structure ; ,
A method of manufacturing a liquid crystal device, comprising: a second breaking step of dividing the medium-sized panel structure on which the medium-sized polarizing plate is bonded , into individual liquid crystal panels, after the polarizing plate bonding step.   2. The method of manufacturing a liquid crystal device according to claim 1, wherein in the second breaking step, cutting is performed using a laser beam.

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