JP4160012B2 - Manufacturing method of liquid crystal display device - Google Patents

Description

The present invention, by a dispenser, relates to the production how the liquid crystal display device to draw sealing material to the outer peripheral portion of the substrate of the liquid crystal display device.

  In manufacturing a liquid crystal display device, in order to enclose liquid crystal in a pair of substrates, a procedure of applying a sealant around the substrates by a dispenser method is taken. Here, the sealing material has a substantially square shape and is applied in a shape in which an injection port for injecting liquid crystal is opened. Then, the substrate thus coated with the sealing material is bonded to another substrate by a vacuum pressure bonding method, and the liquid crystal is sealed in the sealed space portion sealed by the pair of substrates and the sealing material.

  In manufacturing a liquid crystal display device, in order to manufacture a plurality of liquid crystal display devices, after performing various treatments on a single large substrate, the substrate is cut to obtain a plurality of liquid crystal display device substrates. It has been made. In the sealing material application process, the sealing material is applied to a single substrate by a dispenser method for each enclosure space of each liquid crystal display device substrate a plurality of times.

  However, when applying the sealing material with a dispenser, the injection amount of the sealing material becomes unstable immediately after the start of the application of the sealing material, so the technique described in Patent Document 1 has been proposed. The technique described in Patent Document 1 tries to solve the above problem by connecting the sealing materials of adjacent liquid crystal display devices to one stroke when applying the sealing material. More specifically, a dummy that cuts and discards the sealing material that forms the sealed space portion of each liquid crystal space portion (hereinafter, the sealing material that forms the sealed space portion may be referred to as “main seal material”). The sealing material is applied to the shape connected with the sealing material.

  However, in the technique described in Patent Document 1, in the process of performing the heat treatment with a vacuum press that bonds a pair of substrates, due to the pressure difference inside and outside the enclosed space of the liquid crystal display device, There is a problem that a seal break (hereinafter referred to as a “seal pass”) occurs due to omission. In addition, in the bag path formed by the dummy seal part and a part of the main seal part facing this (the inlet part and the seal part facing the dummy seal part), the seal material is not fully crushed and near the seal. In this case, the cell thickness unevenness is generated, and this is also considered to be caused by the differential pressure in the bag path. In other words, the bag path portion has a problem that the air is difficult to escape and is a narrow area, so that the seal of the corner portion is not particularly crushed and the cell thickness of the portion increases.

  On the other hand, when the substrates are bonded to each other by the vacuum pressure bonding method, the technique described in Patent Document 2 is used to eliminate damage to the sealing material due to the pressure difference between the enclosure space for enclosing the liquid crystal and the outside. Proposed. The technique described in Patent Document 2 is such that a substantially U-shaped or C-shaped dummy seal material is applied to the outer periphery of the main seal material forming the liquid crystal enclosure space so as to surround the main seal material. As a result, the pressure difference between the liquid crystal space for enclosing the liquid crystal and the seal material and the dummy seal material is prevented from being generated, and the seal material is prevented from being damaged when the pair of substrates are vacuum-bonded. I am trying.

However, in the method of arranging the dummy seal portion on the outer periphery of the liquid crystal display device as in the technique described in Patent Document 2, the number of liquid crystal display devices arranged on the liquid crystal display device substrate decreases, and the liquid crystal display device substrate There is a problem that the space other than the liquid crystal display device is increased and the cost of the liquid crystal display device is increased.
JP 2001-183681 A JP 2000-29048 A

  Therefore, the present invention has an object to prevent the occurrence of a seal pass, to suppress the occurrence of cell thickness unevenness in the vicinity of the seal, and to suppress the separation failure at the time of division.

  The present invention has been made to solve the above-described problems, and a feature of the liquid crystal display device manufacturing method according to the present invention is that a sealing space is applied to enclose a liquid crystal between a pair of substrates. A method of manufacturing a liquid crystal display device having a sealing material application process in which a portion is formed so as to have an injection port for injecting liquid crystal, and in the sealing material application process, a plurality of enclosed spaces are formed in one substrate. In addition, a sealing material is applied so as to connect the inlets of the adjacent enclosed space portions to form a dummy seal portion, which is formed by the dummy seal portion and the sealing material in the enclosed space portion when the vacuum state is reached. Based on the differential pressure between the bag path and the enclosed space, the shapes of the bag path and the enclosed space are defined.

  In the manufacturing method of the liquid crystal display device having the above-described configuration, even if the vacuum bonding is performed so that the substrate coated with the sealing material as described above is bonded to another substrate, the difference between the bag path portion and the enclosed space portion. Since the pressure is in a certain range, it is possible to prevent the occurrence of a seal pass in the sealing material forming the enclosed space, and to suppress the occurrence of uneven cell thickness in the vicinity of the seal.

In particular , the manufacturing method of the liquid crystal display device according to the present invention is characterized in that a sealing material is applied and an enclosing space for enclosing liquid crystal is formed between a pair of substrates so as to have an injection port for injecting liquid crystal. A method of manufacturing a liquid crystal display device including a sealing material application step, wherein, in the sealing material application step, a sealed space portion having a substantially rectangular shape and having one inlet formed on one side is formed on a single substrate. by applying a sealing material so as to connect the inlet ends of enclosure space adjacent as well as several forms formed by forming a dummy seal portion, and the dummy seal portion at the time that a vacuum state and the sealing material of the enclosure space The shape of the bag path portion and the enclosed space portion formed by the above is within the range of the following formula.
0.1 <[(b + g) × S2 ÷ d] ÷ [(a + g) × S1 ÷ f] <3
S1 = b × c, S2 = a × e
a: length (inside dimension) in the inlet forming direction of the bag path portion, b: length (inside dimension) in the inlet forming direction of the enclosed space portion, c: length in the inlet forming vertical direction of the enclosed space portion, d: length in the vertical direction (internal dimension) of the inlet between the sealed spaces, e: length in the vertical direction of the inlet of the bag path (internal dimension), f: length in the vertical direction of the inlet of the inlet Length (inner dimensions), g: width of sealing material, S1: area of enclosed space, S2: area of bag path

  In the manufacturing method of the liquid crystal display device having the above-described configuration, even if the vacuum bonding is performed so that the substrate coated with the sealing material as described above is bonded to another substrate, the difference between the bag path portion and the enclosed space portion. The pressure is in a certain range, and it is possible to prevent the occurrence of a seal pass in the sealing material forming the enclosed space, and to suppress the occurrence of uneven cell thickness in the vicinity of the seal.

  Furthermore, when the said structure is employ | adopted, it is preferable to employ | adopt the structure whose length (a) of the injection path formation direction of a bag alley part is 1 mm or more. As a result, it is possible to more accurately suppress the occurrence of uneven cell thickness in the vicinity of the seal, and it is possible to suppress a division failure during division.

  By using the manufacturing method of the present invention, it is possible to prevent a seal pass and to suppress occurrence of uneven cell thickness in the vicinity of the seal. Moreover, it becomes possible to suppress the division failure at the time of division.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram for explaining an application pattern of the sealing material in the present embodiment. FIG. 2 is an explanatory diagram for explaining an application pattern of a sealing material in another embodiment. FIG. 3 shows the results of experiments based on the same embodiment.

  In the manufacturing method of the present embodiment, a surface treatment step of forming an electrode, an alignment film or the like on the surface of the substrate, a sealing material application step of applying a sealing material to the surface-treated substrate with a dispenser, A bonding process for bonding the substrate coated with this sealing material and another substrate, a liquid crystal sealing process for sealing liquid crystal between a pair of substrates, and a pair of substrates sealed with liquid crystal for each liquid crystal display device And a cutting step for cutting. In addition, the broken line in FIG. 1 is a cutting line in a cutting process, and the board | substrate 4 is cut | disconnected for every liquid crystal display device along this cutting line.

  In the bonding step, the substrate that has undergone the sealing material application step and the substrate that has undergone the surface treatment step are bonded together by a bonding apparatus, heat treatment is performed in a vacuum press apparatus, and main baking of the substrate is performed. The two are pasted together.

  Further, in the sealing material application step, the sealing material 1 is applied to one substrate 4 so as to form a plurality of enclosing space portions 3 for enclosing liquid crystal in one substrate. The enclosed space 3 is substantially rectangular and has a shape in which one injection port 5 is formed on one side (upper side). In addition, the sealing material 1 that forms the enclosed space 3 may be hereinafter referred to as a “main sealing material”. The sealing space 3 will be described in more detail. In this embodiment, the injection port 5 is formed at the center of the upper side of the rectangular shape, and the upper side and the side, the side and the bottom are all formed at right angles. Also, the sealing material forming the injection port 5 and the upper side are formed at right angles.

  A plurality of the enclosed spaces 3 are provided in the injection port formation direction (vertical direction in FIG. 1) and the injection port formation vertical direction. In the illustrated example, four in the vertical direction, five in the horizontal direction, A total of ten enclosed spaces are formed in the substrate.

  Further, in the sealing material application process, the sealing material 1 is applied so as to connect the injection ports 5 of the adjacent enclosed space portions 3 to form a dummy seal portion, whereby the plurality of enclosed space portions 3 and the dummy spaces are formed. The seal part is formed by drawing with a dispenser (applying a seal material along the directions I to II in FIG. 1).

  More specifically, the inlet 5 of the enclosure space 3 and the inlet 5 of the enclosure space 3 adjacent to the enclosure space 3 in the injection port formation vertical direction are mutually connected to the sealing material 1 (dummy seal part). ), And a plurality of enclosed spaces 3 in the injection port formation vertical direction are formed by one dispenser application. In this embodiment, the dummy seal portion is formed at right angles to the seal portion that forms the injection port 5 of the enclosed space portion 3.

In addition, the application of the sealing material takes into account the pressure difference when the vacuum state of the bag path portion 2 formed by the dummy seal portion and the sealing material of the sealing space portion 3 and the sealing space portion 3 is in a vacuum state. The shapes of the part 2 and the enclosed space part 3 are determined. Specifically, in this embodiment, the shape of the bag path portion 2 and the enclosed space portion 3 is determined based on the following formula.
1 <[(b + g) × a × e ÷ d] ÷ [(a + g) × b × c ÷ f] <3.0
a: length (inside dimension) in the inlet forming direction of the bag path portion, b: length (inside dimension) in the inlet forming direction of the enclosed space portion, c: length in the inlet forming vertical direction of the enclosed space portion, d: length in the vertical direction (internal dimension) of the inlet between the sealed spaces, e: length in the vertical direction of the inlet of the bag path (internal dimension), f: length in the vertical direction of the inlet of the inlet Length (inner dimension), g: width of sealing material The length a in the injection port forming direction of the bag path is set to 1 mm or more.

  According to the manufacturing method having the above configuration, when vacuum bonding is performed in the bonding step, the differential pressure between the bag path portion 2 and the enclosed space portion 3 is in a certain range, and a seal path is formed in the sealing material forming the enclosed space portion 2. It is possible to prevent the occurrence and to suppress the occurrence of uneven cell thickness in the vicinity of the seal.

  Moreover, since the length (a) in the injection port forming direction of the bag path portion 2 is 1 mm or more, it is possible to more accurately suppress the occurrence of cell thickness unevenness in the vicinity of the seal, and to suppress the division failure in the division step. Is possible.

  In addition, although the said embodiment employ | adopted the said structure, this invention is not limited to this, A design change is possible suitably in the range which this invention intends.

That is, for example, as shown in FIG. 2, it is also possible to separately apply a sealing material 1a in the passage formation direction on the passage toward the bag path. In this case, when the above-described formula is applied, the length (inner dimension) d in the vertical direction of the injection port formation of the gap between the enclosed spaces is sealed from the distance between the extensions of the adjacent enclosed spaces. A numerical value obtained by subtracting the width g of the material 1a can be used. That is, it is determined based on the following formula, where h is the distance between the extensions of adjacent enclosed space portions.
0.1 <[(b + g) × a × e ÷ (h−g)] ÷ [(a + g) × b × c ÷ f] <3.0
(Experimental example)
The result of making each numerical value different by the manufacturing method described in the above embodiment is shown in FIG.

  The “expression value” in FIG. 3 is a value calculated by [(b + g) × a × e ÷ d] ÷ [(a + g) × b × c ÷ f]. As is apparent from FIG. 3, a good panel was obtained in the region where the above-mentioned formula value was larger than 0.1 and smaller than 3. Experimental Example 6 is an experiment of the configuration shown in FIG.

  Moreover, the result of having created Comparative Examples 1 to 3 under the same conditions and performing the evaluation is shown in FIG. As apparent from FIG. 3, when the above formula value is 0.1 or less, a seal pass occurs, when the value is 3 or more, cell thickness unevenness occurs, and when a is less than 1 mm, a separation failure occurs.

It is explanatory drawing explaining the seal pattern in the manufacturing method of one Embodiment of this invention. It is explanatory drawing explaining the seal pattern in the manufacturing method of other embodiment of this invention. It is a table | surface which shows an experiment example.

Explanation of symbols

1 Seal Pattern 2 Bag Path 3 Enclosed Space 4 Glass Substrate 5 Inlet

Claims (3)

A manufacturing method of a liquid crystal display device having a sealing material application step of applying a sealing material and forming an enclosing space for enclosing liquid crystal between a pair of substrates so as to have an injection port for injecting liquid crystal,
In the sealing material coating step, a substantially rectangular shape, for connecting the enclosed space having a shape one form inlet on one side, the inlet ends of enclosure space adjacent as well as multiple forms formed on one substrate Apply a sealing material to form a dummy seal part,
A method of manufacturing a liquid crystal display device, characterized in that the shape of the bag path portion and the enclosed space portion formed by the dummy seal portion and the sealing material of the enclosed space portion in a vacuum state is within the range of the following equation .
0.1 <[(b + g) × S2 ÷ d] ÷ [(a + g) × S1 ÷ f] <3
S1 = b × c, S2 = a × e
a: length (inside dimension) in the inlet forming direction of the bag path portion, b: length (inside dimension) in the inlet forming direction of the enclosed space portion, c: length in the inlet forming vertical direction of the enclosed space portion, d: length in the vertical direction (internal dimension) of the inlet between the sealed spaces, e: length in the vertical direction of the inlet of the bag path (internal dimension), f: length in the vertical direction of the inlet of the inlet Length (inner dimensions), g: width of sealing material, S1: area of enclosed space, S2: area of bag path A method of manufacturing a liquid crystal display device according to claim 1 ,
A method of manufacturing a liquid crystal display device, wherein the length (a) of the bag path portion in the injection port forming direction is 1 mm or more. A manufacturing method of a liquid crystal display device according to claim 1 or 2 ,
A method of manufacturing a liquid crystal display device comprising a step of bonding a pair of substrates together by a vacuum press after the sealing material application step.

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