JP2003200336A - Chamfering method for liquid crystal display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chamfering method for a liquid crystal display panel that can flexibly adapt to a change in thickness of a chamfered portion of a liquid crystal display panel and can simply and appropriately chamfer a corner of a transparent substrate. <P>SOLUTION: A grinding tool 22 where a hard abrasive is mixed in a flexible material is used to chip away corner edges 16 of transparent substrates 3 and 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for chamfering a liquid crystal display panel, and more particularly to a method for chamfering a liquid crystal display panel which is suitable for finishing an end face of a transparent substrate of the liquid crystal display panel using a grindstone.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display device utilizing optical rotation of liquid crystal molecules has been widely used as a display means for a mobile phone or a vehicle, because of its high contrast.

FIG. 4 shows a basic structure of such a conventionally adopted liquid crystal display device. The liquid crystal display device 1 has a liquid crystal display panel 2 which performs a main function for liquid crystal display. have. This liquid crystal display panel 2
Has two transparent substrates 3 and 4 made of glass or the like facing each other, and both transparent substrates 3 and 4 are attached to each other via a frame-shaped seal 5. The liquid crystal 7 is enclosed in the space surrounded by the transparent substrates 3 and 4 and the seal 5. Both transparent substrates 3, 4
A pair of transparent electrodes 8 and 9 made of ITO (Indium Tin Oxide) or the like is formed on both inner surfaces facing each other. An alignment film 10 that has been rubbed in a predetermined direction is formed on both transparent electrodes 8 and 9.
Further, a pair of polarizing plates 1 is provided outside the transparent substrates 3 and 4.
2 and 13 are provided, and the polarization directions of the transmitted light from the light source 14 such as a backlight are regulated by the polarizing plates 12 and 13.

Of the two transparent substrates 3 and 4, one transparent substrate 4 shown below in FIG. 4 is formed to have a larger plane direction dimension than the other transparent substrate 3, and this large transparent substrate is formed. Portion (hereinafter referred to as the terminal portion substrate portion 4a
Terminal) 9a of the transparent electrode 9.

In the past, when manufacturing such a liquid crystal display device 1, there has been a case where the work of cutting the transparent substrates 3 and 4 from the mother substrate into a predetermined size is performed.

The transparent substrates 3 and 4 are cut by, for example, dividing a so-called multi-faced mother bonded substrate into individual liquid crystal display panels 2 of a predetermined size, or exposing the liquid crystal 7 injection port as it is. There are various modes such as dividing into strips for cutting or cutting to pull out the terminal portion substrate portion 4a.

In this cutting operation, for example, a crack line is placed at a position where a mother glass substrate is cut by a glass scriber made of diamond, and a break machine pressurizes the crack line from the back surface to divide the crack line.

As shown in FIG. 5, the transparent substrates 3 and 4 which have been subjected to the above-mentioned cutting process have a cutting surface 15 on the outer peripheral end surface, and the outer peripheral end surface on which the cutting surface 15 is formed is formed. A sharp edge 16 is provided at the end on the substrate thickness direction side.
Are formed.

The sharper the edge 16 is, the more brittle it is. In particular, glass having a low impact resistance is not only easily damaged by the impact, but also has a microcrack on the edge 16. Called length 0.01 to 0.1 m
When a minute crack of about m is generated, the crack may propagate to the inside of the transparent substrates 3 and 4 in which the liquid crystal 7 is enclosed and destroy the sealed space in which the liquid crystal 7 is enclosed.

Therefore, it is not possible to leave the ends of the transparent substrates 3 and 4 in the state where the corner edges 16 are formed.
It also causes microcracks, which in turn hinders proper liquid crystal display.

From the viewpoint of eliminating this cause in advance, conventionally, in the manufacturing process of the liquid crystal display device 1, the corner edges formed at the end portions on the substrate thickness direction side of the outer peripheral end surfaces of the transparent substrates 3 and 4. A chamfering method has been adopted in which the portion 16 is cut off to finish the end face of the liquid crystal display panel.

In order to chamfer the liquid crystal display panel 2 as described above, first, as shown in FIG. 6, a V-shaped polishing groove 19 which is recessed in the radial direction is formed on the outer peripheral surface of a substantially cylindrical main body 18. A grindstone 20 formed in the direction is prepared, and the grindstone 20 is brought into contact with both transparent substrates 3 and 4 of the liquid crystal display panel 2 mounted on a stage (not shown) through the grinding groove 19. At this time, both ends of the outer peripheral end surface of the liquid crystal display panel 2 in the substrate thickness direction are in contact with the polishing groove 19. More specifically, in the polishing groove 19, the corner edge 16a formed at the upper end of the outer peripheral end surface of the upper transparent substrate 3 in FIG. 7 and the outer peripheral end surface of the lower transparent substrate 4 in FIG. The corner edge portion 16b formed at the lower end portion of is contacted together.

Then, from this state, as shown in FIG. 6, the grindstone 20 is rotated from the outer peripheral end faces of the transparent substrates 3 and 4 while being rotated by a rotating means (not shown) such as a motor, and along the outer peripheral end faces. By sliding it relative to the liquid crystal display panel 2, the corner edge portions 16a and 16b of both transparent substrates 3 and 4 are scraped off and end face finishing is performed.

The grindstone 20 is formed by jointly molding an abrasive such as diamond.

There are also a plurality of modes for the chamfering described above. For example, in the chamfering called C chamfering, the corner edge portion 16 is cut off into an isosceles triangular shape having a predetermined size, and R is chamfered.
In chamfering, which is called chamfering, the corner edge portion 16 is cut off into an arc shape having a predetermined radius.

[0016]

By the way, in the past, a hard grindstone 20 made of diamond or the like was used for chamfering the liquid crystal display panel 2, but such grindstone 20 can be used to identify the liquid crystal display panel 2, for example. For example, the size of the polishing groove 19 is designed so as to correspond only to the portion having the above thickness. Therefore, a certain restriction may be imposed on the target portion to be chamfered. For example, as described above, in the liquid crystal display panel 2, the display portion including the overlapping portions of the transparent substrates 3 and 4 and the terminal portion substrate portion 4a have different thicknesses, but as shown in FIG. In addition, when the size of the polishing groove 19 is formed so as to correspond only to the display portion, it is not possible to properly chamfer the terminal portion substrate portion 4a.

Further, although the above-mentioned microcracks are apt to occur at the corners (corner edges) of the transparent substrates 3 and 4, since the conventional hard grindstone 20 has been used for chamfering, it is particularly concerned. We could not flexibly deal with chamfering of corners. Accordingly, in order to chamfer the corner edges 16 formed at the corners of the transparent substrates 3 and 4 to chamfer the corners, the liquid crystal display panel 2 for the grindstone 20 is used.
However, complicated work changes such as changing the direction of the blade and the direction of movement of the grindstone are indispensable, and yet the problem of microcracks at the corners has not been properly resolved.

The present invention has been made in view of the above problems, and by using a grindstone having flexibility,
(EN) A chamfering method for a liquid crystal display panel, which can flexibly cope with a change in the thickness of a chamfered portion of the liquid crystal display panel and can easily and properly chamfer the corners of a transparent substrate. It is intended.

[0019]

In order to achieve the above object, the method of chamfering a liquid crystal display panel according to claim 1 of the present invention is characterized in that a grindstone in which a hard abrasive is mixed in a flexible material. Is used to remove the corner edge of the transparent substrate.

By adopting such a method, chamfering can be performed with a grindstone having flexibility, so that it is possible to flexibly cope with changes in the thickness of the chamfered portion of the liquid crystal display panel. Further, since the grindstone can be appropriately slidably contacted to the corner edge portion formed on the corner portion of the transparent substrate by utilizing its flexibility, the corner edge portion can be simply made without requiring complicated work change. And it can be chamfered properly.

A feature of the chamfering method of the liquid crystal display panel according to claim 2 is that in the claim 1, a grindstone made of a rubber material mixed with an abrasive material or a resin material mixed with an abrasive material is used.

By adopting such a method, the dimensional change of the liquid crystal display panel can be flexibly dealt with by a simple method, and the corners can be chamfered easily and appropriately.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a chamfering method for a liquid crystal display panel according to the present invention will be described below with reference to FIGS.

The same reference numerals will be used for parts having the same or similar basic structure as the conventional ones.

In the present embodiment, by rotating the grindstone along the outer peripheral end faces of the transparent substrates 3 and 4 and sliding it relative to the liquid crystal display panel 2, the substrate thickness direction of the transparent substrates 3 and 4 is increased. Edge 16 formed at the side end
It is the same as the conventional one in that the chamfering is performed by removing

However, in this embodiment, as shown in FIG. 1, the chamfering is performed by using a substantially cylindrical grindstone 22 in which a hard abrasive is mixed in a flexible material, which is different from the conventional method. Have a difference.

By using such a grindstone 22, it is possible to flexibly cope with the change in shape of the chamfered portion of the liquid crystal display panel 2.

That is, even when the display portion of the liquid crystal display panel 2 on which the two transparent substrates 3 and 4 are superposed as shown in FIG. 2 is chamfered, as shown in FIG. Even when the substrate portion 4a is chamfered, the shape of the outer peripheral surface of the grindstone 22 can be flexibly changed according to the thickness of the liquid crystal display panel 2 slidingly contacting the outer peripheral surface. LCD display panel 2
Can be properly slidably contacted with the outer peripheral end face of the.

As a result, of the upper and lower transparent substrates 3 and 4 shown in FIG. 2 which form the display portion, the corner edge portion 16 formed on the upper end portion of the outer peripheral end surface of the upper transparent substrate 3 and the lower one. The corner edges 16 formed at the lower end portion of the outer peripheral end surface of the transparent substrate 4 can be removed, and the corners formed at the upper and lower end portions of the outer peripheral end surface of the terminal portion substrate portion 4a shown in FIG. The edge 16 can be scraped off.

Therefore, the same grindstone 22 can properly chamfer both the display portion and the terminal portion substrate 4a having different thicknesses.

Further, by utilizing the flexibility of the grindstone 22, the grindstone 22 can be properly slidably contacted with both the corners (corner edges) of the display section and the corners of the terminal section substrate 4a. By using the same grindstone 22, the corner edges 16 formed at the respective corners of the liquid crystal display panel 2 can be scraped off to properly chamfer the corners. Therefore, the whetstone 2
By rotating the outer periphery of the liquid crystal display panel 2 relative to the liquid crystal display panel 2 while rotating 2, it is possible to chamfer all corners of the transparent substrates 3 and 4 including the terminal portion substrate portion 4a. Is also possible.

As a result, the chamfering of the corners of the transparent substrates 3 and 4 of the liquid crystal display panel 2 can be easily and properly performed by a single operation without requiring a complicated work change, and the micro-angles at the corners can be improved. The generation of cracks can be effectively prevented.

As the material having flexibility,
For example, a rubber material or a resin material may be used, and the abrasive may be diamond, for example.

In this case, since it is possible to select a suitable material that imparts flexibility to the grindstone 22, the liquid crystal display panel 2 can be chamfered more appropriately.

Next, the test results of a comparative test for comparing the end face finishing effect by the chamfering method of the liquid crystal display panel to which this embodiment is applied and the conventional chamfering method of the liquid crystal display panel will be described.

In the chamfering method of the present embodiment, the particle size of the abrasive mixed with the flexible material is #
220 to # 600, the diameter of the main body is 100 to 2
A grindstone having a thickness of 00 mm and a thickness of 10 to 50 mm is rotated at a rotation speed of 400 to 1500 times per minute to chamfer the chamfering amount by C chamfering. The side dimension is 0.1 to 0.3 m.
m.

On the other hand, in the conventional chamfering method, the chamfering was performed at the same number of revolutions and chamfering amount using the diamond grindstone having the same diameter and thickness of the main body as in the present embodiment.

As a result, in the conventional chamfering method,
It took 15 seconds to chamfer the corners of one liquid crystal display panel.

On the other hand, in the chamfering method of the present embodiment, the chamfering of the corner portion of one liquid crystal display panel can be performed in 4 seconds, and the time required for the chamfering is almost 1/1 of that of the conventional method.
I was able to shorten to 4.

In the present embodiment, this is because the grindstone can be appropriately slidably brought into contact with any corner of the display portion and the terminal portion substrate portion having different thicknesses by utilizing its flexibility. Therefore, it is presumed that each corner can be properly chamfered without requiring a complicated work change.

Therefore, according to this embodiment, the chamfering can be performed by the grindstone 22 having flexibility, so that it is possible to flexibly cope with the change in the thickness of the chamfered portion of the liquid crystal display panel 2, and display Even if the thicknesses of the portion and the terminal portion substrate portion 4a are different, the same grindstone 22 can properly chamfer the liquid crystal display panel 2.

Further, since the grindstone 22 can be appropriately slidably contacted to the corners of the transparent substrates 3 and 4 by utilizing its flexibility, the corners can be simply and easily made without any complicated work change. Can be properly chamfered.

The present invention is not limited to the above-mentioned embodiment, but various modifications can be made if necessary.

For example, in the relative sliding between the grindstone 22 and the liquid crystal display panel 2, only the grindstone 22 may be slid along the outer periphery of the liquid crystal display panel 2, or the grindstone in the rotating state. Only the liquid crystal display panel 2 may be slid with respect to 22 manually or automatically, or both the grindstone 22 and the liquid crystal display panel 22 may be moved.

[0045]

As described above, according to the chamfering method of the liquid crystal display panel according to the first aspect of the present invention, it is possible to easily and properly prevent the generation of microcracks, and thus the quality of the liquid crystal display device. In addition, reliability and manufacturing efficiency can be improved.

According to the chamfering method of the liquid crystal display panel of the second aspect, in addition to the effect of the chamfering method of the liquid crystal display panel of the first aspect, it is possible to properly prevent the generation of microcracks.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a chamfering method for a liquid crystal display panel according to the present invention.

FIG. 2 is a schematic side view showing a chamfered state of a display unit in the embodiment of the chamfering method of a liquid crystal display panel according to the present invention.

FIG. 3 is a schematic side view showing a chamfered state of the terminal board portion in the embodiment of the liquid crystal display panel chamfering method according to the present invention.

FIG. 4 is a schematic cross-sectional view showing the basic configuration of a liquid crystal display device that has been conventionally used.

FIG. 5 is a schematic side view showing a problem caused by cutting the transparent substrate.

FIG. 6 is a schematic perspective view showing an example of a conventional liquid crystal display panel chamfering method.

FIG. 7 is a front view of FIG.

[Explanation of symbols]

2 Liquid crystal display panel 3 transparent substrate 4 transparent substrate 4a Terminal part substrate part 16 corner edge 22 whetstone

Claims (2)

[Claims] 1. At least transparent electrodes are formed on both inner surfaces of two transparent substrates, which have a cut surface on the outer peripheral end face thereof and are bonded to each other via a seal, and liquid crystal is sealed between the two transparent substrates. With respect to the liquid crystal display panel, in a state in which a grindstone is in contact with the outer peripheral end surface of the transparent substrate, by sliding the grindstone relative to the liquid crystal display panel along the outer peripheral end surface, In a chamfering method of a liquid crystal display panel, which is performed by chamfering a corner edge portion formed along the edge of the outer peripheral end on the substrate thickness direction side, a hard abrasive is mixed in a flexible material. A chamfering method for a liquid crystal display panel, characterized in that the corner edge portion of the transparent substrate is shaved off by using a grindstone. 2. The chamfering method for a liquid crystal display panel according to claim 1, wherein a grindstone made of a rubber material mixed with an abrasive material or a resin material mixed with an abrasive material is used.