JPH0743731A - Device for press welding liquid crystal panel - Google Patents

Abstract

PURPOSE:To provide a device for press welding liquid crystal panels capable of simultaneously producing many pieces of panel bodies for encapsulating liquid crystals under uniform pressing conditions. CONSTITUTION:Plural pieces of partition walls 13 are superposed on each other and are fastened by means of bolts 21 to form plural pieces of substrate housing chambers 14 between the respective partition members 13. Substrate assemblies 9 in an unadhered state are housed in the respective substrate housing chambers 14 and are airtightly supported by O-rings 15. Respective inner regions U divided by these O-rings 15 are exposed via apertures 17 or communicating holes 19 to the atm. pressure. On the other hand, the respective outer regions S are discharged through the openings 18 for discharge by a pump 20 to reduce the pressure in the cell gap G in the respective substrate assemblies 9. The respective substrate assemblies 9 are held by uniform pressing force free from variations between the respective substrate assemblies 9 by the effect of a differential pressure. The plural panel bodies for encapsulating the liquid crystals are simultaneously obtd. if the entire part is heated in an oven.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a liquid crystal display (L
The present invention relates to a liquid crystal panel pressure bonding device used when manufacturing a liquid crystal panel which is a component of CD. In particular, the present invention relates to a liquid crystal panel pressure bonding device used for adhering a pair of opposed substrates constituting a liquid crystal panel to each other while sandwiching them under pressure.

[0002]

2. Description of the Related Art In a liquid crystal display, a pair of glass substrates provided with transparent electrodes are usually adhered to each other with a minute gap left therebetween to form a panel body for enclosing a liquid crystal, and the liquid crystal is enclosed in the minute gap. It is manufactured by encapsulating the liquid crystal panel, and then by mounting auxiliary elements such as a printed circuit board and a backlight on the obtained liquid crystal panel. Then, when manufacturing a panel body for liquid crystal encapsulation, first, for example, a large number of spherical or cylindrical spacers are arranged on one of a pair of glass substrates, and the seal portion is frame-shaped around the spacers by screen printing or the like. Print. Then, the other glass substrate is pressed against the glass substrate by sandwiching the spacer and the seal portion with an appropriate pressure, and in this pressed state, the glass substrate is wholly heated to heat and cure the seal portion so that both glass substrates are heated. The substrates are glued together.

Conventionally, a device for manufacturing a panel body for enclosing a liquid crystal by bonding a pair of glass substrates as described above, that is, a liquid crystal panel crimping device, has been disclosed in, for example, Japanese Patent Laid-Open No. 1-257824. As described above, the pair of partition members (panel pressure bonding device main body) keeps the vicinity of the outer edge of the unbonded liquid crystal panel airtight, exposes a wide area in the center of the unbonded liquid crystal panel to atmospheric pressure, and further There is known an apparatus in which both glass substrates are uniformly pressed by reducing the minute gap between the glass substrates of the unbonded liquid crystal panel, that is, the cell gap, by exhausting the vicinity of the outer edge.

[0004]

However, in the conventional liquid crystal panel pressure bonding device exemplified in Japanese Patent Laid-Open No. 1-257824, only one liquid crystal encapsulating panel body can be obtained by one treatment. However, in order to obtain a large number of liquid crystal encapsulating panel bodies, the processing for that purpose must be repeated a large number of times, and the workability was extremely poor.

The present invention has been made to solve the above problems, and provides a liquid crystal panel pressure bonding apparatus capable of simultaneously producing a large number of liquid crystal encapsulating panel bodies under extremely uniform pressing conditions. The purpose is to

[0006]

In order to achieve the above object, the liquid crystal panel crimping device according to the present invention is stacked in layers to form a plurality of panel accommodating chambers for accommodating unbonded liquid crystal panels. A plurality of partition members arranged and annularly supporting the unbonded liquid crystal panel in each panel housing chamber, and the panel housing chamber including an inner region including a central portion of the unbonded liquid crystal panel and an outer region including an outer edge portion of the unbonded liquid crystal panel. A sealing member for supporting the substrate that is airtightly divided into two regions, a high-pressure communication hole that is provided in each partition member, and that communicates the inner regions of the panel accommodating chambers to the same high-pressure atmosphere, and the substrate support. Exhaust opening provided in the partition wall member for communicating the outer regions of the respective panel accommodating chambers sealed by the airtight sealing member, and the exhaust means for decompressing the outer regions of the respective panel accommodating chambers. The it has.

In this liquid crystal panel pressure bonding device, an opening for visually confirming the inside of the panel accommodating chamber is provided in at least one of the two partition members on the front and back sides of the plurality of partition members, and this opening is provided. It can be used as the high-pressure communication hole.

Further, an auxiliary sealing member may be provided at a position outside the exhaust opening in the outer region of each panel storage chamber to enhance the airtightness of the outer region of the panel storage chamber.

In the above description, the high-pressure atmosphere means an atmosphere having a relatively high atmospheric pressure as compared with a region decompressed by the exhaust means, and means an atmosphere pressurized to a high pressure by a pressurizing pump or the like. Not a thing. Therefore,
A high-pressure atmosphere can be created even at atmospheric pressure or lower pressure.

[0010]

A plurality of panel accommodating chambers are formed between a plurality of partition wall members, and one unbonded liquid crystal panel is accommodated in each panel accommodating chamber. Then, each unbonded liquid crystal panel is supported in each panel accommodating chamber by the substrate supporting sealing member,
At that time, each panel housing chamber is airtightly divided into two regions, an inner region and an outer region, by the sealing member. Each outer region is depressurized to an equal pressure through the pressure reducing connecting hole, and each inner region is maintained at an equal high pressure, for example, atmospheric pressure through the high pressure connecting hole. As a result, a common differential pressure is generated between the inner region and the outer region in each panel storage chamber, and the pair of substrates in each unbonded liquid crystal panel are held in a state of being uniformly pressed by each other due to this differential pressure. . When each unbonded liquid crystal panel thus pressed by the equal pressure difference is put into a heating device such as an oven together with the liquid crystal panel pressure bonding device and heated, the seal part in each unbonded liquid crystal panel is cured by heating and sandwiches it. The substrates are adhered to each other, and as a result, a plurality of liquid crystal encapsulating panel bodies are simultaneously manufactured.

[0011]

First, prior to describing an embodiment of a liquid crystal panel pressure bonding device, a liquid crystal display which is a target of the pressure bonding device will be described by way of an example. Figure 2
Shows an example of a liquid crystal panel that constitutes a liquid crystal display, and a liquid crystal display is manufactured by mounting auxiliary elements such as a printed circuit board and a backlight on the liquid crystal panel 12. The liquid crystal panel 12 is usually in a state after the opposing glass substrates 1 and 2 are adhered to each other and the liquid crystal is sealed in the cell gap G formed between them, in contrast to this. In the specification, a state in which the opposing glass substrates 1 and 2 are simply laminated and not yet bonded is referred to as an unbonded liquid crystal panel 9, and the opposing glass substrates 1 and 2 are bonded to each other, but the cell gap G A state in which no liquid crystal is sealed inside is referred to as a liquid crystal sealing panel body 10.

The liquid crystal panel 12 is manufactured, for example, by the following method. First, the glass substrate 1 and the glass substrate 2 are individually prepared, and a transparent conductive film (ITO) is individually formed on them by a thin film forming process such as sputtering, and then the pixel is formed according to a well-known photolithography or etching method. The electrodes 3a and 3b are formed in a predetermined pattern.

Next, an insulating film (S) is formed on the glass substrates 1 and 2 on which the electrodes are formed by sputtering or the like.
iO ₂ ) 4a and 4b are separately provided, and polyimide alignment films 5 and 6 are further applied thereon by spin coating or the like, and then the individual glass substrates 1 and 2 are further coated with, for example, 1
Bake at 80 ° C for 1 hour.

After that, the alignment film 5 on one glass substrate 1
Is subjected to an alignment treatment such as rubbing to uniaxially align the polyimide molecules. Separately from this, a positive photoresist is applied by spin coating or the like on the other glass substrate 2 on which the alignment film 6 is formed, and then a process such as photolithography is performed to form the spacer 7 and the seal portion 8. . Here, the spacer 7 is composed of a plurality of linear projections extending linearly in parallel to each other in the direction perpendicular to the plane of the drawing. Further, the seal portion 8 is formed in a frame shape on the outer edge portions of both glass substrates 2. At this stage, the two glass substrates 1,
No. 2 has not been pasted yet.

After that, the two glass substrates 1 and 2 formed as described above are overlapped with each other in a predetermined position as shown in FIG. 2 to form an unbonded liquid crystal panel 9. . Then, a plurality of such unbonded liquid crystal panels 9, at least three in the case of the embodiment, are prepared and mounted in the liquid crystal panel pressure bonding device 11 as shown in FIG. As will be described in detail later, this panel pressure bonding device 11 presses and holds each unbonded liquid crystal panel 9 with a uniform pressure from both front and back directions of the pair of glass substrates 1 and 2 facing each other.

Next, the entire panel pressure bonding device 11 holding the unbonded liquid crystal panel 9 is placed in a heating device such as an oven, and the glass transition point of the positive photoresist forming the spacer 7 and the seal portion 8 or the vicinity thereof. Heat to temperature. Then, after heating for a predetermined time, it is gradually cooled to room temperature.

After the above work, the liquid crystal panel pressure bonding device 11
Is dismantled, a plurality of liquid crystal encapsulating panel bodies 10 in which the opposing glass substrates 1 and 2 are bonded to each other by the heat-cured spacer 7 and the seal portion 8, in the case of the embodiment, three are produced at the same time. It Considering that a ferroelectric liquid crystal, an antiferroelectric liquid crystal, or the like is used as the liquid crystal to be sealed in the liquid crystal sealing panel body 10, the liquid crystal sealing panel body 10 has a space between the glass substrates 1 and 2 facing each other. The minute gap G for enclosing the liquid crystal, so-called cell gap, is set to a very narrow gap of 2.5 to 1.5 μm, for example.
A liquid crystal panel 12 is manufactured by injecting liquid crystal into the cell gap G through the seal portion 8 and further sealing the seal portion 8.

The liquid crystal panel pressure bonding apparatus 11 (FIG. 1) according to the present invention is used in the above liquid crystal panel manufacturing process when the unbonded liquid crystal panel 9 is pressed at a predetermined pressure and put in an oven or the like for firing. The configuration will be described in detail below.

As shown in FIGS. 1 and 3, the liquid crystal panel crimping device 11 has a plurality of partition members 13 stacked in the vertical direction, that is, four partition members 13 in the embodiment. Each partition member 13
Is made of a rigid material such as metal, and as shown in FIG. 3, its overall shape is substantially square. By stacking these partition members 13 in the vertical direction of FIG. 1 and further fastening them by an appropriate number of bolts 21, a plurality of spaces, three spaces in the embodiment, are provided between the partition members.
That is, three panel accommodating chambers 14 are formed, and one of the unbonded liquid crystal panels 9 is formed in each of the panel accommodating chambers 14.
It is housed individually.

Each unbonded liquid crystal panel 9 accommodated is vertically supported at its outer edge portion by a pair of upper and lower small-diameter square rubber O-rings 15 serving as a substrate supporting sealing member. These O-rings 15 airtightly divide each panel storage chamber 14 into two regions, an inner region U and a ring-shaped outer region S surrounding the inner region U. A wide central portion of the unbonded liquid crystal panel 9 is included in the inner area U, while an outer peripheral edge portion of the unbonded liquid crystal panel 9 is included in the outer area S.

A square window opening 17 as shown by a chain line in FIG. 3 is provided at the center of each partition member 13. Further, in FIG. 1, an exhaust opening 18 is opened in a portion corresponding to the outer region S of each partition member 13 excluding the uppermost partition member 13a. Further, a high pressure communication hole 19 for communicating each window opening 17 with the atmosphere is provided on the left side of the middle two partition members except the highest partition member 13a and the lowest partition member 13b. There is. An exhaust pump 20 as an exhaust unit is connected to the exhaust opening 18 of the lowermost partition member 13b. At a position outside the exhaust opening 18 in the outer region S of each panel accommodating chamber 14, a large-diameter, square-annular shape serving as an auxiliary sealing member for increasing the airtightness of the outer region S is formed, if necessary. Rubber O-ring 2
2 is fitted.

Since the liquid crystal panel pressure bonding device 11 according to this embodiment is configured as described above, the glass substrates 1 of the respective unbonded liquid crystal panels 9 housed in layers inside the device.
The central wide portion of 2 (see FIG. 2) is exposed to atmospheric pressure through the window opening 17 or through the high pressure communication hole 19.
On the other hand, by operating the exhaust pump 20, the outer region 18 of each panel housing chamber 14 is exhausted through each exhaust opening 18 to be depressurized, and as a result, each unbonded liquid crystal panel 9 is exhausted.
The inside of the cell gap G is reduced in pressure through the seal portion 8 at the outer edge portion.

As described above, the wide portions of the surfaces of the glass substrates 1 and 2 are exposed to the atmospheric pressure, and the cell gap G is further reduced. Differential pressure is applied. Due to the action of this pressure difference, each unbonded liquid crystal panel 9 is held in a state of being pressed extremely uniformly over the entire surface, and therefore,
The cell gap G in each unbonded liquid crystal panel 9 is set to the spacer 7
Can be accurately maintained at uniform intervals defined by Moreover, since the differential pressures acting on the three unbonded liquid crystal panels 9 are exactly equal to each other, there is no variation in the cell gap condition between the unbonded liquid crystal panels 9. Each unbonded liquid crystal panel 9 thus pressed can be observed from the outside through the window opening 17. And in particular, the uppermost partition member 13a
The window opening 17 of the lowermost partition member 13b also functions as a high-pressure communication hole for exposing the inner region U of the panel housing chamber 14 to the atmospheric pressure.

Each unbonded liquid crystal panel 9 pressed and held as described above is put together with the liquid crystal panel pressure bonding device 11 in an oven or the like to be heated, and after a certain period of time, it is taken out from there and gradually cooled, whereby the spacers 7 and As described above, the seal portion 8 is heated and cured to bond the pair of glass substrates 1 and 2 to each other to obtain the liquid crystal encapsulating panel body 10.

As is apparent from the above description, if the liquid crystal panel pressure bonding device of this embodiment is used, all of the plurality of unbonded liquid crystal panels 9 housed in one liquid crystal panel pressure bonding device 11 can be applied with exactly the same pressure. Since they can be sandwiched, a plurality of liquid crystal encapsulating panel bodies 10 having no variation in the cell gap G can be simultaneously manufactured.

By the way, in the TN type liquid crystal display, the cell gap can be set to about 7 to 10 μm, and in the STN type liquid crystal display, the cell gap can be set to a relatively wide interval such as 5 to 6 μm. On the other hand, in the ferroelectric liquid crystal display, it is necessary to set the cell gap to be extremely narrow, such as 2.5 to 1.5 μm. In connection with this, in the panel pressure bonding apparatus of the present embodiment, the unbonded liquid crystal panel 9 is clamped by utilizing not the mechanical pressing pressure but the differential pressure generated between the atmospheric pressure and the reduced pressure. So 1
The pressing force distribution for the one unbonded liquid crystal panel 9 is also uniform, and the pressing force distribution among the plurality of unbonded liquid crystal panels 9 is also uniform. Therefore, even when the gap between the cell gaps G needs to be extremely narrow as in the case of using the ferroelectric liquid crystal, a liquid crystal panel can be manufactured without causing defective products.

Although the present invention has been described with reference to one embodiment, the present invention is not limited to the embodiment but can be variously modified within the technical scope described in the claims.

For example, the structure of the liquid crystal panel to which the present invention can be applied is not limited to the structure shown in FIG. 2, and various other liquid crystal panel structures can be used. Further, the present invention is extremely advantageous for a liquid crystal display having a narrow cell gap such as the case where a ferroelectric liquid crystal is used, but of course, it is naturally applicable to TN type, STN type and various other types of liquid crystal displays. Applicable.

The shape of the partition wall member 13 and the method for fastening each partition wall member 13 are not limited to the illustrated embodiment.
Further, the number of partition wall members 13 stacked is not limited to four as in the illustrated embodiment.

[0030]

According to the present invention, since a plurality of liquid crystal encapsulating panel bodies can be manufactured at the same time, the productivity of liquid crystal panels is improved. In addition, since the unbonded liquid crystal panels are arranged in layers, it is not necessary to have a large area for placing the liquid crystal panel pressure bonding device. Therefore, it is not a dedicated oven and is a relatively small size that is generally used. Can be placed in the oven. Further, since the outer regions of the respective panel accommodating chambers are communicated with each other through the exhaust opening provided in each partition member, the exhaust means can be commonly used, which is advantageous in terms of space and cost.

Further, since the pair of glass substrates is sandwiched by utilizing the differential pressure generated between the high pressure atmosphere such as atmospheric pressure and the reduced pressure atmosphere created by the exhaust treatment, the mechanical press treatment is used. The pressing force applied to the plurality of unbonded liquid crystal panels stacked in layers can be made more uniform between the unbonded liquid crystal panels as compared with the case of sandwiching.

[0032]

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a liquid crystal panel pressure bonding device according to the present invention.

[FIG. 2] A liquid crystal panel manufactured by using the liquid crystal panel pressure bonding device, a liquid crystal encapsulation panel body before liquid crystal is encapsulated in the liquid crystal panel, or a pair of glass substrates constituting the liquid crystal encapsulation panel body are bonded to each other. FIG. 3 is a side sectional view showing the unbonded liquid crystal panel in a state before being processed.

3 is a plan sectional view showing a liquid crystal panel pressure bonding device according to a line III-III in FIG.

[Explanation of symbols]

 1 Glass Substrate (Counter Substrate) 2 Glass Substrate (Counter Substrate) 7 Spacer 8 Sealing Section 9 Non-Adhesive Liquid Crystal Panel 10 Liquid Crystal Encapsulation Panel Body 12 Liquid Crystal Panel 13 Partition Member 14 Panel Housing 15 Small O-Ring (Substrate Support Sealing Member) ) 17 Window opening 18 Exhaust opening 19 High pressure communication hole 20 Exhaust pump 22 Large diameter O-ring (auxiliary sealing member) G Cell gap U Inner region of panel storage chamber S Outside region of panel storage chamber

Claims (3)

[Claims] 1. A liquid crystal panel crimping device for sandwiching, under pressure, a non-bonded liquid crystal panel in which a pair of opposed substrates are sandwiched with a spacer and a seal portion sandwiched therebetween, and a plurality of panel housing chambers for housing the non-bonded liquid crystal panel. A plurality of partition members arranged in layers to form a panel, and a panel accommodating chamber that annularly supports the unbonded liquid crystal panel in each panel accommodating chamber and an inner region including a central portion of the unbonded liquid crystal panel. A substrate supporting sealing member that airtightly divides into two regions, an outer region including an outer edge portion of the adhesive liquid crystal panel, and an inner region of each panel accommodation chamber, which is provided in each partition member, communicates with each other in a high pressure atmosphere. A high-pressure communication hole, and an exhaust opening provided in the partition wall member for communicating the outer regions of the respective panel storage chambers sealed by the respective substrate supporting sealing members with each other, The liquid crystal panel crimping machine and having an exhaust means for reducing the outer region of the panel accommodating chamber. 2. An opening for visually confirming the inside of the panel accommodating chamber is provided in at least one of the two partition members on the front and back sides of the plurality of partition members, and the opening is used for the high pressure communication hole. The liquid crystal panel crimping device according to claim 1, which is used as. 3. The liquid crystal panel crimping device according to claim 1, wherein an annular auxiliary sealing member is provided at a position outside the exhaust opening in an outer region of each panel storage chamber.