JPH09281515A - Production of liquid crystal element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for holding large substrates effective under a reduced pressure as well and a method for executing simple lighting inspection of liquid crystal elements in a process for production for obtaining the plural liquid crystal elements for a pair of the large substrates. SOLUTION: The large substrates 20, 30 having the plural electrode substrates constituting the liquid crystal elements are stuck to each other via frame-shaped sealing materials 41 enclosing the electrode substrates in such a manner that the parts (test terminal substrate parts) not superposing on each other are obtainable with the large substrates 20, 30 by sealing a liquid crystal material into the frame. The sure holding of the respective substrates 20, 30 to the holding table of an apparatus for production of sticking to each other is made possible even under the reduced pressure by fixing such test terminal parts. The adjacent signal electrodes of the respective electrode substrates are connected to connection wirings 22U, 22D and are connected by sorting the scanning electrodes 31 by one piece each to connection wirings 32L, 32R and are drawn out as test terminals 22Ut, 22Dt, 32Lt, 32Rt to the test terminal substrate parts. The lighting inspection of the liquid crystal elements is executed by impressing driving signals without cutting the large substrates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a plurality of liquid crystal elements from two large substrates which are bonded together, and improves the accuracy of bonding positions and a lighting test, that is, whether or not a drive electrode is broken or short-circuited. The present invention relates to a manufacturing method capable of easily performing the inspection.

[0002]

2. Description of the Related Art FIG. 7 and FIG. 8 show a state in which two large substrates are bonded together in the manufacturing process of a conventional simple matrix type liquid crystal display device. (The corners of the board in the figure are not
FIG. 7 is a plan view showing a state in which two large substrates are bonded together to form a plurality of liquid crystal display elements (hereinafter, this state is referred to as a unit), and FIG. 8 is A- in FIG. It is sectional drawing of A part.

On large substrates 1 and 2 made of a transparent material such as a plurality of glass and divided into a plurality of regions, a plurality of signal electrodes 3 as scanning electrodes and scanning electrodes 4 are laid in the respective divided regions. An electrode substrate is formed. An alignment film (not shown) for aligning the liquid crystal substance is formed on the electrode substrates. The large substrate 1 and the large substrate 2 are attached to each other at regular intervals via a frame-shaped sealing material 5 arranged so as to surround the electrode substrate. A liquid crystal substance is enclosed in a space surrounded by the pair of electrode substrates and the sealing material 5. Then, the large substrates 1 and 2 are respectively cut along a dividing line of the large substrate 1 indicated by a chain double-dashed line C1 and a dividing line of the large substrate 2 indicated by a double-dashed chain line C2 in the drawing to obtain a target liquid crystal display element. .

[0004]

In the conventional method of manufacturing a liquid crystal display element as described above, a method of dividing the above-mentioned unit and then enclosing the liquid crystal substance through the injection port provided in the sealing material 5 is used. Came. However, in order to further increase productivity, a method of encapsulating a liquid crystal substance in a plurality of cells when forming a unit has been attempted.

However, this method has the following problems in the manufacturing process. This is because the large substrates 1 and 2 are bonded together under reduced pressure in order to prevent bubbles from being generated in the liquid crystal layer during bonding. That is, normally, a large substrate is held on a holding table by vacuum suction, but the suction force is proportional to the pressure difference between the front surface and the back surface at that time and the area of the large substrate. Since it becomes extremely weak, the positions of the large substrates 1 and 2 are likely to be displaced according to a method in which the substrates are held on a holding table by a vacuum suction method and then the large substrates are aligned and bonded by the alignment mark.

Further, since the signal electrodes 3 and the scanning electrodes 4 are not exposed to the outside in the state of the unit, the lighting inspection for checking the disconnection and the short circuit of the drive electrodes cannot be carried out until the liquid crystal elements are divided.

Therefore, it is an object of the present invention to provide a method for holding a large substrate that is effective even under reduced pressure and a method for performing a simple lighting inspection of a liquid crystal element before division.

[0008]

Means for Solving the Problems The above-mentioned problem is to supply a liquid crystal to either one of a pair of electrode substrates having a plurality of stripe-shaped drive electrodes formed on their respective surfaces, and then seal the pair of electrode substrates with a sealing material. In the method for manufacturing a liquid crystal element, the surface of the first large substrate is divided into a plurality of regions, and the drive electrodes are laid in the individual regions to form one of the plurality of electrode substrates. The second large substrate, the surface of the second large substrate is divided into a plurality of regions, the drive electrodes are laid in the individual regions, and the other of the plurality of electrode substrates is formed on the first large substrate. Corresponding to one of the first large substrate and the second large substrate, a test terminal substrate portion is formed on the first large substrate and the second large substrate so as not to overlap with each other. Holds each large substrate when joining the second large substrate. Stand the test terminal board section is fixed by a jig to be solved by a method of manufacturing a liquid crystal device characterized by holding each said entire large substrate to the holding table.

Further, the above problem is that a liquid crystal is supplied to either one of a pair of electrode substrates having a plurality of stripe-shaped drive electrodes formed on their respective surfaces, and then the pair of electrode substrates are bonded via a sealant. In the method for manufacturing a liquid crystal element, the surface of the first large substrate is divided into a plurality of regions, and the drive electrodes are laid in the respective regions to form one of the plurality of electrode substrates. The surface of the second large substrate is divided into a plurality of regions, and the drive electrodes are laid in the individual regions so that the other of the plurality of electrode substrates corresponds to one of the electrode substrates on the first large substrate. To form the first
Of the drive electrodes adjacent to the first large substrate and the second large substrate by forming test terminal substrate portions on the large substrate and the second large substrate that do not overlap with each other. Two common wirings for connecting every other one are formed for each of the electrode substrates, the corresponding drive electrodes of each electrode substrate are connected, and are drawn out to the test terminal substrate portion to form the first test terminal and the second test terminal. The test terminals are formed respectively, and a drive signal is applied to all the test terminals of the first large substrate and the second large substrate which are bonded and filled with liquid crystal between the opposing electrode substrates, The presence or absence of disconnection of the drive electrode is inspected, and the first
Of the first or second test terminal of the large substrate and the drive of applying the drive signal to only one of the first or second test terminal of the second large substrate. The problem can also be solved by a method for manufacturing a liquid crystal element, which is characterized by inspecting for a short circuit between electrodes.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described based on an example applied to a simple matrix type liquid crystal display element.
In this example, 2 rows × 3 from the state where two large substrates are bonded together
A total of 6 liquid crystal display elements in a row are formed.

FIG. 1 is a plan view of a state in which two large substrates are bonded together (hereinafter referred to as a unit). The large substrates 20 and 30 made of a pair of transparent substrates are rectangular. FIG.
Is a large substrate 2 hidden in the other large substrate 30 in FIG.
It is a plan view of only 0. The drive electrodes of these liquid crystal display elements are composed of signal electrodes 21 and scan electrodes 31.

As shown in FIG. 2, the large substrate 20 is provided with stripe-shaped signal electrodes 21 made of a plurality of transparent conductive films.
It is formed in parallel for each of the regions divided into a plurality. On one of the large substrates 30, stripe-shaped scan electrodes 31 made of a plurality of transparent conductive films are formed in parallel in each of a plurality of divided regions. These regions on the large substrates 20 and 30 are hereinafter referred to as electrode substrates.

On the large substrates 20 and 30 on which the signal electrodes 21 and the scanning electrodes 31 are formed, an alignment film (not shown) for controlling the alignment of liquid crystal molecules serves as a display screen in a display section 40.
Is formed.

Then, each display section 40 of the electrode substrate on one side
A plurality of frame-shaped sealing materials 41 are formed so as to surround the, and a predetermined amount of liquid crystal substance (not shown) is dropped in advance in the frame,
The large substrate 20 and the large substrate 30 are bonded together via the frame. After the bonding, the liquid crystal substance is sealed in the frame of the sealing material 41. At this time, in the bonding direction of the two large substrates, the long sides are orthogonal to each other so that the short sides of the large substrates 20 and 30 do not overlap each other, and in the display section 40, the signal electrode 21 and the scanning electrode are arranged. The direction 31 is orthogonal. Thus, on the large substrates 20 and 30,
Regions of the test terminal board portion that do not overlap with the other large board are generated respectively (when the large boards 20 and 30 are both square, it is possible to cope with the method described later instead of the bonding method of this example. ).

In FIG. 2, a plurality of signal electrodes 21 of a plurality of electrode substrates are formed in parallel on the large substrate 20 in a stripe shape in the display section 40 so as to be aligned in the vertical direction in the figure. Adjacent signal electrodes 21 are wider than the signal electrodes 21 and are connected by connection wirings 22U and 22D in which a transparent conductive film or another metal film having a lower resistance such as Cr or Al is laminated thereon. This configuration is shown in FIG. 3, which is an enlarged view of a portion of FIG.

In FIG. 3, the signal electrodes 21 are connected to the terminal side of the electrode substrate (upward in the figure) and the opposite terminal side of the electrode substrate (downward in the figure) every other different connection wiring 22U (terminal side). ),
It is distributed and connected to the connection wiring 22D (non-terminal side).
The connection wirings 22U and 22D are connected to the test terminals 22Ut and 22Dt arranged on the test terminal board portion located on the two short sides of the large board 20.

The other large substrate 30 will be described with reference to FIG. 1, but FIG. 1 shows a state in which the large substrate 30 is viewed from the back side. On the large substrate 30, the scanning electrodes 31 of a plurality of electrode substrates are formed in parallel in a plurality of stripes arranged in the display unit 40 in the horizontal direction in the drawing. Adjacent scan electrodes 31 are wider than the scan electrodes 31 and are connected by connection wirings 32L and 32R in which a transparent conductive film or another metal film having a lower resistance such as Cr or Al is laminated thereon. This configuration is shown in FIG. 4, which is an enlarged view of a part of FIG. 1 (the wiring on the large substrate 30 is viewed from the back surface side, as in FIG. 1).

In FIG. 4, the scanning electrodes 31 in the display section 40 are shown.
Are alternately connected to the left and right terminals of the electrode substrate, and in the figure, the left terminal is connected to the left connection wiring 32L and the right terminal is connected to the right connection wiring 32R. The connection wirings 32L and 32R are the test terminals 32Lt and 3L arranged on the test terminal board located on the two short sides of the large board 30.
It is connected to 2Rt.

In this way, the drive signal is applied to the above-mentioned test terminals 22Ut and 22D to the unit bonded as shown in FIG.
By inputting from t, 32Lt, 32Rt, it is possible to carry out a lighting inspection for all the liquid crystal display elements included in the unit and check for disconnection and short circuit of the drive electrodes of the liquid crystal display elements. At this time, optical elements such as a polarizing plate and a retardation plate for adjusting optical conditions for incident light and emitted light of the liquid crystal display element are prepared on the lighting inspection machine side.

In this embodiment, the test terminals 22Ut and 22Dt of the large board 20 and the test terminals 3 of the large board 30 are used.
Although 2Lt and 32Rt are installed on each two sides, only one side may be provided. Alternatively, the connection wirings 22U and 22D of the signal electrode 21 of one large board 20 are interposed between the large boards 20 and 30 facing each other with a conductive resin or the like at a predetermined position of the large boards 20 and 30, and the other large board 30. The connection wirings 22U and 22D are guided to the large substrate 30 and the test terminals 22Ut and
22Dt and test terminals 32Lt and 32R of the scan electrode 31
Both t may be laid.

A method of manufacturing the liquid crystal element having the above structure will be described. With respect to the two large substrates 20 and 30, the transparent conductive film and the metal film are laminated in this order, and the signal electrodes 21 and
Connection wirings 22U, 22D, scan electrodes 31, connection wiring 32
Lay L and 32R. Then, the metal films of the signal electrodes 21 and the scanning electrodes 31 in the display section 40 are removed. As a result, the signal electrode 21 and the scanning electrode 31 are laid by wiring made of a transparent conductive film, and the connection wirings 22U, 22D, 32L, 32R are laid by two-layer wiring made of a transparent conductive film and a metal film. In addition,
In the case of a small liquid crystal display element or a liquid crystal display element having a wide driving electrode, the process is simplified if it is formed of a single layer of a transparent conductive film.

Next, an alignment film (not shown) is formed on the display section 40 for the large substrates 20 and 30, and an alignment process is performed. Then, in order to bond the two large substrates, a frame-shaped sealing material 41 is formed with a constant thickness so as to surround each electrode substrate on one large substrate 20. And
A liquid crystal substance is dropped into the frame of the sealing material 41 by a dispenser or the like.

The large substrate 20 onto which the liquid crystal substance has been dropped and the large substrate 30 described above are transferred into a vacuum container, and the test electrode substrate is fixed to the holding table of the bonding apparatus with a jig. Are held on the holding table of the above apparatus. At this time, it is performed under vacuum in order to exclude air in the frame to seal the liquid crystal in the frame of the sealing material 41 when the large substrates 20 and 30 are bonded together. Then, after confirming and correcting the position on the holding table with a positioning mark or the like, the long side of the large substrate 30 is attached so that the long side thereof is orthogonal to the long side of the other large substrate 20.

In this bonding step, the structure of this embodiment brings a new effect. In the conventional method of bonding without providing a portion that does not overlap the large substrate, the large substrate is held on the holding table of the manufacturing apparatus by vacuum suction on the back surface. However, this method of sucking the back surface has a weak suction force under vacuum, and therefore cannot reliably hold the back surface, and is easily displaced from a predetermined position during positioning and bonding.

Therefore, in this embodiment, the large substrates 20, 30 are used.
The long sides are orthogonalized and the short sides are adhered to each other via the sealing material 41 so that the short sides do not overlap each other, thereby generating a test terminal board portion in which the large boards do not overlap each other, and this portion is formed by a jig. It is sandwiched and fixed, and the large substrates 20, 30 can be securely held on the holding table of the above-described manufacturing apparatus.

FIG. 5 shows a sectional view of the holding table of the manufacturing apparatus according to the holding method of this embodiment. The bonding manufacturing device is a jig 5 for holding the holding bases 50 and 51 and the large substrates 20 and 30.
2.

The large board 20 is held by fixing the test terminal board portions, which are not overlapped with the facing large board 30, to the holding table 50 by jigs 52 at least at two places. At this time, avoid the aforementioned test terminals 22Ut and 22Dt in the place where the test terminal board is fixed.

On the other hand, the large substrate 30 is attached to the holding base 51 by the large substrate 2
After holding by the same method as 0, turn it upside down
Turn 0 downwards. (The drawing has already been inverted.) Then, the alignment marks provided in advance on the large substrates 20 and 30 are confirmed, the holders 51 are adjusted by movement, and then the substrates are bonded.

The jig 52 of each of the holding bases 50 and 51 has a convex portion, but the jig 5 of the holding bases 51 and 50 facing each other is convex.
No restriction is imposed if the position corresponding to 2 is dug in like a recess 52 'of the holding table (the holding table 50 side is not shown). The above method is effective not only under reduced pressure but also under normal pressure.

The following lighting inspection can be performed on the units bonded as described above.
Since there is no non-overlapping portion in the unit shown in FIG. 7 manufactured by the conventional manufacturing method, the drive signal could not be supplied to each electrode in this state.

The lighting inspection is performed for each liquid crystal display element.
Two test terminals 22Ut, 22Dt, 32Lt, 32R
It is performed by applying a drive signal to t, and is divided into a full lighting test in which the drive signal is applied to all electrodes and a half lighting test in which the drive signal is applied to only half of the electrodes. In this inspection, the state in which the drive signal is not applied is displayed in black, and the state in which it is applied is displayed in white.

The all-lighting inspection is carried out as follows to inspect for a disconnection, a short circuit between the signal electrode 21 and the scanning electrode 31 (a short circuit between opposing electrode substrates), and the like. A drive signal is applied to the test terminals 22Ut, 22Dt connected to the signal electrode 21, and the test terminals 32Lt, 3 connected to the scan electrode 31.
A drive signal is applied to 2Rt.

In this state, each display section 40 is observed, and if a linear black line is observed, it means that the drive electrode is broken in that direction. If a cross-shaped black line is observed, it means that the signal electrode 21 and the scanning electrode 31 are short-circuited, that is, the electrode substrates facing each other are short-circuited. Further, in this inspection, point defects such as white spots and black spots caused by defective alignment of the liquid crystal substance are also observed.

The semi-lighting inspection is carried out as follows to inspect for a short circuit between the signal electrodes 21 or the scanning electrodes 31. One of the two test terminals 22Ut and 22Dt connected to the plurality of electrode substrates on the large substrate 20 and the large substrate 3
Two test terminals 3 connected to multiple electrode substrates on
A drive signal is applied to one of 2Lt and 32Rt.
At this time, every other one of the signal electrodes 21 and the scanning electrodes 31 is in a state where the drive signal is input.

In this state, each display section 40 is observed,
Normally, every other line should be lit, but if three consecutive drive electrodes are lit, white display is considered to be a short circuit between the stripes. Further, the above-described black line, black cross line, and dot-like abnormality in the electrode to which the drive signal is applied are some of the defects observed in the above all-lighting inspection.

After this lighting inspection, the unit proceeds to the next step. The unit is the chain double-dashed line C20 in FIG. 1 and FIG.
(Large substrate 20), C30 (Large substrate 30) dividing line (FIG. 1 shows the large substrate 30, FIG. 2 shows the dividing line of the large substrate 20) is divided into individual liquid crystal display elements. To be done. Then, the non-defective product advances to the next inspection process, and the manufacturing process of the liquid crystal display element is completed.

In this example, the long sides of the two large substrates are orthogonal to each other, but there are other methods.
FIG. 6 shows the method. The large substrates 20 and 30 may be moved in an oblique direction as shown in the drawing, and this case can also be applied to the case of square large substrates.

Further, regarding the implementation of the present invention, it is not necessary that the two large substrates to be bonded have the same shape, and different shapes can be applied.

[0039]

The liquid crystal device manufactured by the manufacturing method of the present invention is advantageous to the manufacturer in two respects as compared with the conventional liquid crystal device.

The first point is to improve the alignment accuracy of a large substrate. According to this manufacturing method, it is possible to reliably hold the large substrate by the jig. Therefore, by previously setting the alignment marks and the like on each of the pair of large substrates, it is possible to confirm the marks and correct the positions while the large substrates are held on the holding table, and then bond them together. As a result, the positional accuracy of bonding can be improved from the conventional accuracy of the outer shape of the substrate (several hundreds of μm level) to the position accuracy of the mark and the holding table (several tens of μm or less).

The second point is the simplification of implementation of the lighting inspection. Since the lighting inspection is performed in the unit state, the number of inspections is reduced as compared with the case where each divided liquid crystal element is performed, and the existence of defective products can be grasped at a stage before dividing the unit.

[Brief description of drawings]

FIG. 1 is a plan view showing two bonded large substrates in a liquid crystal element manufacturing method according to an embodiment of the present invention.

FIG. 2 is a plan view of the present invention, in which one of the two large substrates of FIG. 1 is removed.

FIG. 3 is a partially enlarged view of FIG. 2 of the present invention.

FIG. 4 is a partially enlarged view of FIG. 1 of the present invention.

FIG. 5 is a cross-sectional view of a holding base of a bonding manufacturing apparatus in a liquid crystal element manufacturing method as an embodiment of the present invention.

FIG. 6 is a plan view showing another example different from the embodiment of the present invention.

FIG. 7 is a plan view showing two large substrates that are bonded together in a conventional liquid crystal element manufacturing method.

8 is a cross-sectional view showing a cross section taken along the line AA of FIG. 7 of the related art.

[Explanation of symbols]

1, 2, 20, 30 ... Large substrate 3,21 ... Signal electrode 4,31 ... Scan electrode 40 ... Display unit 5,41 ... Seal material 22U, 22D, 32L, 32R. ..Connecting wirings 22Ut, 22Dt, 32Lt, 32Rt ... Test terminals 50, 51 ... Holding table 52 ... Jig 52 '... Recessed portion C1, C2, C20, C30 ... Split line

Claims (2)

[Claims] 1. A liquid crystal obtained by supplying a liquid crystal to one of a pair of electrode substrates having a plurality of stripe-shaped drive electrodes formed on their respective surfaces and then joining the pair of electrode substrates through a sealant. In the device manufacturing method, the surface of the first large substrate is divided into a plurality of regions, and the drive electrodes are laid in each of the regions to form one of the plurality of electrode substrates, and the second large substrate is formed. The surface of each of the electrodes is divided into a plurality of regions, the drive electrodes are laid in the respective regions, and the other of the plurality of electrode substrates is formed so as to correspond to one of the electrode substrates on the first large substrate. , A test terminal board portion is formed on the first large substrate and the second large substrate so as not to overlap with each other, and the first large substrate and the second large substrate are joined together. When
A method for manufacturing a liquid crystal element, comprising: fixing the test terminal board portion to a holding table for holding each large substrate by a jig, and holding each of the large boards on the holding table. 2. A liquid crystal formed by supplying a liquid crystal to either one of a pair of electrode substrates having a plurality of stripe-shaped drive electrodes formed on their respective surfaces and then joining the pair of the electrode substrates through a sealing material. In the device manufacturing method, the surface of the first large substrate is divided into a plurality of regions, and the drive electrodes are laid in each of the regions to form one of the plurality of electrode substrates, and the second large substrate is formed. The surface of each of the electrodes is divided into a plurality of regions, the drive electrodes are laid in the respective regions, and the other of the plurality of electrode substrates is formed so as to correspond to one of the electrode substrates on the first large substrate. A test terminal board portion is formed on the first large substrate and the second large substrate so as not to overlap with each other, and adjacent to the first large substrate and the second large substrate. Two connection wirings for connecting every other drive electrode in common Is formed for each of the electrode substrates, and the corresponding drive electrodes of each electrode substrate are connected and drawn out to the test terminal substrate portion to form a first test terminal and a second test terminal, respectively, and the opposite electrode substrate A drive signal is applied to all the test terminals of the first large substrate and the second large substrate, which are filled with a liquid crystal and bonded to each other, and the presence or absence of disconnection of the drive electrode is inspected. Of the first or second test terminal of the large substrate and the drive of applying the drive signal to only one of the first or second test terminal of the second large substrate. A method for manufacturing a liquid crystal element, which comprises inspecting for a short circuit between electrodes.