JP3830278B2 - Liquid crystal display device manufacturing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device manufacturing apparatus, and more specifically, is applied when a pair of transparent electrode substrates are bonded together via a peripheral sealing material and then heated and pressurized to thermally cure the peripheral sealing material. The present invention relates to an apparatus for manufacturing a liquid crystal display element.
[0002]
[Prior art]
FIG. 3 schematically shows a cell substrate of a liquid crystal display element cut out as a product unit from a multi-sided mother substrate. According to this, the cell substrate 1 includes a pair of transparent electrode substrates 2 and 3 each having a transparent electrode made of an ITO (Indium Tin Oxide) pattern.
[0003]
These transparent electrode substrates 2 and 3 have a peripheral sealing material 4 printed on one of the substrates, and an in-plane spacer (not shown) as a gap width regulating means is sprayed on the display surface. , And pasted together through the peripheral sealing material 4.
[0004]
In this case, an electrode terminal portion 3a is continuously provided on one transparent electrode substrate 3 side, and although not shown in detail, each transparent electrode of both the transparent electrode substrates 2 and 3 is connected to the electrode terminal portion 3a. The extraction electrode to be connected is also made of ITO.
[0005]
In addition, a conductive material (particle) as a transfer material is mixed in the peripheral sealing material 4, and the transparent electrode on the transparent electrode substrate 2 side passes through the transfer material to a predetermined lead on the electrode terminal portion 3 a. Connected to the electrode.
[0006]
In the actual manufacturing process, the electrode pattern formation, the printing of the peripheral sealing material, the spraying of the in-plane spacers, and the bonding of the substrates are performed in units of mother substrates. Since the curable resin is used, it is necessary to thermally cure the peripheral sealing material 4 at the stage of the mother substrate before the cell substrate 1 is cut out as a product unit.
[0007]
FIG. 4 shows a conventional example of a thermocompression bonding apparatus used at that time. In the figure, M is a mother substrate. The thermocompression bonding apparatus includes a lower heater table 10 and an upper heater table 20 each of which is controlled to be heated to a predetermined temperature. For example, an electric heater is built in the lower heater table 10, and an appropriate cushioning material 10 a is placed on the table 10.
[0008]
The upper heater table 20 is driven in the vertical direction by elevating means such as a motor (not shown). Moreover, the pressurization part 21 which consists of a diaphragm of the upper heater table 20 is provided, and this upper heater table 20 is connected to the heating air supply source which is not shown in figure.
[0009]
[Problems to be solved by the invention]
In advance, both the heater tables 10 and 20 are heated to a predetermined temperature, and the mother substrate M is set on the cushioning material 10 a of the lower heater table 10. Then, the upper heater table 20 is lowered and the mother substrate M is pressurized by the pressurizing portion 21 to thermally cure the peripheral sealing material 4, but this has the following problems.
[0010]
That is, only one mother substrate M is shown in FIG. 4, but actually, a plurality of the substrates are sequentially stacked on the lower heater table 10 and the thermocompression treatment is performed collectively. However, in the case where a plurality of mother substrates M are sequentially stacked in this way, cleaning is performed for removing each of the substrates and a spacer plate is interposed between each mother substrate M, so that all of them are disposed. A considerable amount of time is required before setting.
[0011]
Therefore, since the lower mother board M set initially is kept heated by the lower heater table 10 until all the mother boards M are set, before being pressurized by the upper heater table 20. Then, curing of the peripheral sealing material 7 proceeds.
[0012]
As a result, even if it is pressed by the upper heater table 20 thereafter, the peripheral sealing material 7 is not crushed to a predetermined gap width, and a conduction failure of the transfer material occurs. Even in a non-transfer model in which no transfer material is mixed into the peripheral seal material 7, there is a problem of display unevenness in the vicinity of the seal due to a gap width variation.
[0013]
However, if the temperature of the lower heater table 10 is lowered from the beginning, the above problem does not occur, but according to this, it takes a long time to heat the peripheral sealing material 4 on the other side, It cannot be said that it is preferable in terms of productivity.
[0014]
The present invention has been made to solve such a problem, and its object is to sequentially stack a large number of cell substrates (including a mother substrate state) on a lower heater table, and then to perform an upper heater. An object of the present invention is to provide an apparatus for manufacturing a liquid crystal display element, in which all cell substrates can be processed under equal conditions when pressure is applied by a table and the peripheral sealing materials are collectively thermocompression bonded.
[0015]
[Means for Solving the Problems]
To achieve the above object, the present invention includes a lower heater table and an upper heater table that can be raised and lowered with respect to the lower heater table, and a pair of transparent electrode substrates made of a thermosetting resin. Manufacturing of a liquid crystal display element that cures the peripheral sealing material by sandwiching and heating a cell substrate of a liquid crystal display element that is bonded via an intermediate heater between the lower heater table and the upper heater table at a predetermined pressure In the apparatus, the lower heater table includes a tray on which the cell substrate is placed and a predetermined time on the lower heater table between the time when heat treatment of the cell substrate is started by the two heater tables. Tray support means for supporting the tray at a height position and bringing the tray into contact with the lower heater table during the heat treatment of the cell substrate is provided. It is characterized.
[0016]
According to this configuration, the tray is supported at a predetermined height position on the lower heater table, that is, in a state of floating from the lower heater table, until the time of starting the heat treatment of the cell substrate by the both heater tables. The cell substrate set in the initial stage does not receive more heat than the other cell substrates laminated thereon, and everything is pressurized and heated under substantially the same conditions.
[0017]
In addition, the cell substrate of the liquid crystal display element in the present invention includes a substrate in a stick substrate and a cell substrate assembled as a single unit in addition to a mother substrate. Further, it goes without saying that the manufacturing apparatus of the present invention is applicable not only when a large number of cell substrates are stacked and collectively processed, but also when thermocompression processing is performed one by one.
[0018]
In the present invention, the tray support means includes a tray receiving pin provided so as to be movable in and out with respect to the lower heater table, and the tray receiving pin against the weight of the tray and the cell substrate placed thereon. It is preferable in terms of structure and cost to be composed of a spring member that is urged so as to protrude from the lower heater table and that yields with the applied pressure when the cell substrate is pressurized.
[0019]
In the present invention, the tray supporting means may be air cylinder driving means or motor driving means for moving the tray up and down with respect to the lower heater table. According to these driving means, the tray can be kept floating from the lower heater table until the pressurization to the cell substrate is completed against the pressurizing force of the upper heater table. is there.
[0020]
The tray is made of a plate material having a relatively small heat capacity, for example, an aluminum, brass or ceramic plate having a thickness of about 2 to 3 mm. A buffer material having a predetermined thickness, for example, Teflon ( (Product name) sheet or silicon rubber sheet is preferably provided.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in more detail on the basis of the embodiments shown in the drawings. In this embodiment, parts that are the same as or the same as those of the conventional example described above are denoted by the same reference numerals.
[0022]
As shown in FIG. 1, also in this embodiment, each has a lower heater table 10 and an upper heater table 20 that can be controlled to a predetermined temperature, and the object to be thermocompression bonded will be described first. Similarly to the mother substrate M including the plurality of cell substrates 1, according to the present invention, the lower heater table 10 has the tray 11 on which the mother substrate M is placed, the tray support means 12 and the like. Is provided.
[0023]
In the present invention, the tray 11 is preferably a plate having a relatively small heat capacity. For example, it is preferably made of aluminum, brass or ceramic and has a thickness of about 2 to 3 mm.
[0024]
A buffer material is provided on the tray 11, but in this embodiment, the buffer material is formed of two layers. That is, on the tray 11, a silicon rubber sheet 111 having a thickness of 1 to 2 mm as a first cushioning material, and a Teflon (trade name) sheet 112 having a thickness of 0.3 mm as a second cushioning material disposed thereon. Are stacked.
[0025]
In this embodiment, as shown in the cross-sectional view of FIG. 2, the tray support means 12 has a tray receiving pin 121 provided so as to be able to protrude and retract with respect to the lower heater table 10, and the tray receiving pin 121 above the tray receiving means 121. And a coil spring 122 that urges toward the end.
[0026]
The tray receiving pins 121 are arranged at, for example, five locations at the four corners and the central portion of the lower heater table 10 and support the tray 11 at a height position of 25 to 35 mm from the surface of the lower heater table 10 at the maximum protrusion. Have a length to get.
[0027]
Further, when the upper heater table 20 is in a non-pressurized state on the coil spring 122, the weight of the tray 11 and the mother substrate M (which may be either a single or a plurality) placed thereon is provided. A compression coil spring is used that has a spring force that urges the tray receiving pins 121 so as to protrude from the lower heater table 10, but yields depending on the pressure applied to the upper heater table 20.
[0028]
As shown in FIG. 2, a recess 101 for accommodating the tray receiving pin 121 and its coil spring 122 is formed at a location where the tray receiving pin 121 of the lower heater table 10 is provided.
[0029]
According to this apparatus, the mother substrate M is thermocompression bonded as follows. First, the lower heater table 10 and the upper heater table 20 are heated to a predetermined temperature (for example, 140 to 190 ° C.). This heating is performed for the lower heater table 10 by an electric heater incorporated therein, and for the upper heater table 20 by heated air from a heating air supply source (not shown).
[0030]
Next, the mother substrate M is placed on the buffer material provided in the tray 11. Although only one mother substrate M is shown in FIG. 1 for convenience of drawing, in this embodiment, three to four mother substrates M are stacked with a spacer plate (not shown) interposed between the substrates. .
[0031]
As described above, the mother substrate M is formed by bonding a pair of transparent electrode substrates through a peripheral sealing material 4 (see FIG. 3) made of a thermosetting resin. Is pre-cured at a temperature equal to or lower than the curing reaction temperature for the purpose of precuring the peripheral sealing material 4 and removing the solvent contained therein.
[0032]
According to this apparatus, since the tray 11 is supported by the tray support means 12 so as to float from the lower heater table 10, each mother board M is cleaned for removing dust one by one, Even when the spacer plates are sequentially stacked on the tray 11 while the spacer plates are arranged between the substrates, the lower mother substrate M set at the beginning receives more heat than the mother substrate M stacked thereafter. Absent.
[0033]
Thereafter, the upper heater table 20 is lowered to pressurize all the mother boards M with a predetermined pressure. By this pressurization, the tray 11 comes into contact with the lower heater table 10. In this embodiment, when each substrate temperature from the substrate setting to the completion of pressurization is measured, the substrate is set in the order of 80 to 65. ° C.
[0034]
On the other hand, in the conventional apparatus shown in FIG. 4, the lower heater table 10 is heated to 140 to 190 ° C. as in this embodiment, and the same number of mother boards M as in this embodiment are placed on the lower heater. When stacking directly on the buffer material 10a of the table 10 and pressurizing with the upper heater table 20, each substrate temperature from the substrate setting to the completion of pressurization was 120 to 80 ° C. in the order of the substrate setting. .
[0035]
Thus, according to the present invention, the temperature of each substrate from the substrate setting to the completion of pressurization can be kept low in the same state as before without lowering the heating temperature of the lower heater table 10. And the variation is small.
[0036]
Therefore, the pressurization can be completed without reaching the reaction start temperature (for example, 120 to 130 ° C.) of the peripheral sealing material 4, and the seal is caused by the occurrence of poor conduction due to excessive heating before the pressurization or the gap width variation. Occurrence of display unevenness in the vicinity is prevented. In addition, as for the material of the peripheral sealing material, conventionally usable materials are limited, but according to the present invention, the degree of freedom of selection of the sealing material can be expanded.
[0037]
Unlike the above embodiment, the tray 11 may be moved up and down by driving means such as a motor or an air cylinder. In the case of using a motor, a pinion-rack mechanism or a feed screw shaft may be used. When such a driving means is employed, the tray can be kept floating from the lower heater table until the pressurization is completed.
[0038]
【The invention's effect】
As described above, according to the present invention, by sandwiching and heating the cell substrate of the liquid crystal display element at a predetermined pressure between the lower heater table and the upper heater table, the peripheral sealing material for the cell substrate Is provided with a tray that can be moved up and down with respect to the lower heater table, and the tray is placed on the lower heater table until the cell substrate is set. By maintaining the height position, it is possible to prevent the occurrence of poor conduction due to excessive heating before pressurization or the occurrence of display unevenness in the vicinity of the seal due to the gap width variation.
[Brief description of the drawings]
FIG. 1 is a front view schematically showing an embodiment of a liquid crystal display device manufacturing apparatus according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part showing a tray support means in the embodiment.
FIG. 3 is a schematic cross-sectional view showing a basic configuration of a cell substrate of a liquid crystal display element.
FIG. 4 is a front view schematically showing a conventional liquid crystal display device manufacturing apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cell substrate 2 of liquid crystal display element 2, 3 Transparent electrode substrate 4 Peripheral sealing material 10 Lower heater table 11 Tray 111,112 Buffer material 12 Tray support means 121 Tray receiving pin 122 Coil spring

Claims (4)

A cell of a liquid crystal display element comprising a lower heater table and an upper heater table that can be raised and lowered relative to the lower heater table, wherein a pair of transparent electrode substrates are bonded together via a peripheral sealing material made of a thermosetting resin In the apparatus for manufacturing a liquid crystal display element that cures the peripheral sealing material by sandwiching and heating the substrate at a predetermined pressure between the lower heater table and the upper heater table,
In the lower heater table, the tray is placed at a predetermined height position on the lower heater table between the tray on which the cell substrate is placed and the start of the heat treatment of the cell substrate by the two heater tables. And a tray supporting means for bringing the tray into contact with the lower heater table during the heat treatment of the cell substrate. The tray support means includes a tray receiving pin provided to be movable in and out of the lower heater table, and the tray receiving pin against the weight of the tray and the cell substrate placed thereon. 2. The apparatus for manufacturing a liquid crystal display element according to claim 1, further comprising a spring member that is urged so as to protrude from the table and that yields when the cell substrate is pressurized. The apparatus for manufacturing a liquid crystal display element according to claim 1, wherein the tray support means comprises air cylinder driving means or motor driving means for moving the tray up and down relative to the lower heater table. 3. The liquid crystal display according to claim 1, wherein the tray is made of a plate material having a relatively small heat capacity, and a buffer material having a predetermined thickness is provided on the liquid crystal display element mounting surface. Device manufacturing equipment.

Images