JPH0545617A - LCD cutting method using a plastic substrate - Google Patents

Abstract

(57) [Summary] [Structure] The LCD cutting method using a plastic substrate is performed by a dicing device equipped with a dicing blade 1. The dicing blade 1 is rotated at a high rotation speed to sandwich the liquid crystal layer. The plastic substrates 2a and 2b thus formed are cut into pieces, and after leaving a predetermined thickness, the pieces are cut off and cut. Further, the laminator 6 is provided on the back surface of the plastic substrates 2a and 2b, the dicing blade 1 is rotated at a predetermined number of rotations, the plastic substrates 2a and 2b sandwiching the liquid crystal layer are cut, and the laminator 6 is left by a predetermined thickness. After that, it may be separated by tearing it off. [Effect] It is possible to suppress the occurrence of cracks on the cross section. In the case where the lead-out dividing process is performed, the electrode pattern and the like are not damaged. L by cutting chips
It is possible to prevent the surface of the CD and the substrate from being scratched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for dividing an LCD (Liquid Crystal Display) using a plastic substrate into cells or terminals.

[0002]

2. Description of the Related Art A conventional LCD is made of glass (300 mm × 300 mm, thickness 0.55 mm to 1.1 m) as a substrate material.
m) is used, an undercoat,
An ITO (Indium-Tin Oxide) electrode, an alignment film and the like (none of which are shown) are formed, and after the alignment treatment, the two glass substrates are bonded together leaving a gap for the liquid crystal layer. In this state, the glass substrate is divided into individual cells (cell dividing treatment), and the portion facing the terminal portion is divided (terminal dividing treatment).

In the case of a glass substrate, after a surface is scratched by a diamond cutter (not shown) or the like along a predetermined cutting line, a breaking device (not shown) gives a shock to the cutting line to cut the substrate. (Break process)
It is like this. In the case of a glass substrate, the scratches on the surface are easily transmitted to the inside of the substrate due to its material, so that the cutting process can be accurately performed along the scratches on the surface. In addition to the above method,
A method is also known in which the substrates are divided in advance and then the substrates are opposed to each other and bonded.

In recent years, in order to make LCDs thinner and lighter, conventional glass substrates have been made thinner, and attempts have been made to make them ultrathin and light by using plastic substrates. .. As a result, TN (Twisted Nematic) type L
Regarding CDs, film base materials have been developed and have been mass-produced. As the film base material, PE
S (Polyether Sulphone) and uniaxial PET (Polyethylene)
Recently, a plastic film having a thickness of 0.1 mm to 0.3 mm such as Telephthalate) has been actively developed.

However, higher quality STN (Super Tw
Isted Nematic) type LCDs are still under development due to problems such as surface flatness, heat resistance and dimensional stability of the film substrate.

When the above-mentioned plastic substrate is used, the cutting process is performed by a hot blade cutting device or a Thomson die punching.

[0007]

The 0.1 mm thick PES, uniaxial PET and the like are currently extruded from a thin slit and molded, so that streaks and the like occur on the surface. Therefore, in order to improve the surface flatness, a method of using a plastic substrate molded using a mold whose surface is polished has been attempted.

As a plastic material suitable for this method, an epoxy resin or an acrylic resin can be used. These materials, which are also used as lenses for eyeglasses, have the property of being hard and brittle. For this reason, in the conventional cutting technique used for glass or the above-mentioned 0.1 mm to 0.3 mm plastic film, the cell dividing process and the lead-out dividing process cannot be performed.

In the case of a substrate made of acrylic resin and epoxy resin having a thickness of about 0.4 mm, since it has a certain elasticity against bending stress, it cannot be cut along a scratch on the surface like a glass substrate. .. Further, when stress is applied, cracking occurs with respect to a stress of a predetermined value or more. When a crack is generated due to the application of a stress of a predetermined value or more, a crack is apt to be generated on this cross section, and there is a problem that the crack further progresses with a small stress from this crack.

In view of the above points, the present invention provides a method for performing cell segmentation and terminal segmentation of an LCD using a hard and brittle plastic substrate typified by epoxy and acrylic resins. ..

[0011]

In order to solve the above-mentioned problems, the invention of claim 1 is a method of dividing an LCD using a plastic substrate which is divided by a dicing device equipped with a blade, and comprises the following steps. Contains.

That is, according to the first aspect of the invention, the blade is rotated at a predetermined rotation speed (for example, 20000 rpm) to cut the plastic substrate holding the liquid crystal layer,
The method includes a step of leaving a predetermined thickness (for example, 50 μm) to be left uncut, and a step of breaking off the uncut portion after the step is finished.

In order to solve the above-mentioned problems, the invention of claim 2 is a method of dividing an LCD using a plastic substrate which is divided by a dicing device equipped with a blade, and includes the following steps.

That is, according to the second aspect of the invention, a step of providing a covering member (for example, a polyethylene film or a polarizing film with a polyethylene film) on the back surface of the plastic substrate and a predetermined rotation speed (for example, 10,000 rpm).
The blade is rotated by to cut the plastic substrate sandwiching the liquid crystal layer, and a step of leaving a predetermined thickness (for example, 30 μm) of the covering member is left, and after the step, the uncut portion is cut off to divide. The process is included.

[0015]

With the structure according to the first aspect of the present invention, the blade of the dicing device is rotated at a predetermined number of rotations, so that cracks generated on the divided surface can be suppressed.

[0016] For example, in the case of performing the terminal division processing, the plastic substrate sandwiching the liquid crystal layer is cut by the blade rotating at the above-mentioned number of revolutions, but since it is left uncut by a predetermined thickness, it is provided on the opposing plastic substrate. There is no damage to the electrode pattern and the like. When the cutting is completed with a predetermined thickness left, the uncut portion is broken off and divided.

On the other hand, in the case of performing the cell dividing process, the plastic substrate holding the liquid crystal layer is cut by the blade rotating at the above rotation speed. At this time, the upper plastic substrate is completely divided by the rotation of the blade, while the lower plastic substrate is left uncut by a predetermined thickness. When the cutting is completed with a predetermined thickness left, the uncut portion is broken off and divided.

The thickness to be left uncut needs to be set so as not to be adversely affected by the force applied to the plastic substrate at the time of breaking.

According to the second aspect of the invention, the covering member is provided on the back surface of the plastic substrate prior to the cutting by the blade. With this covering member, it is possible to prevent the surface of the plastic substrate from being damaged by the cutting dust generated during cutting. This is particularly useful when terminal processing is performed on both the upper and lower substrates.

Then, the blade of the dicing device is rotated at a predetermined rotation speed. By cutting the blade at the number of rotations described above, cracks generated on the dividing surface can be suppressed.

For example, in the case of performing a lead-out cutting process, the upper plastic substrate sandwiching the liquid crystal layer is cut by the blade rotating at the above-mentioned number of rotations, but it is left uncut by a predetermined thickness. The provided electrode pattern and the like are not damaged.
When terminal disconnection processing is performed on both the upper and lower substrates, the upper and lower substrates are turned upside down, and this time the lower plastic substrate is similarly left uncut by a predetermined thickness. And
When the cutting is completed with a predetermined thickness left, the uncut portion is broken off and divided.

On the other hand, when the cell dividing process is carried out, the plastic substrate holding the liquid crystal layer is cut by the blade rotating at the above-mentioned rotational speed. At this time, the upper plastic substrate and the covering member provided thereon and the lower plastic substrate are completely separated by the rotation of the blade, but only the covering member provided on the back surface of the lower plastic substrate is separated. Is left uncut by a predetermined thickness.
Then, when cutting is completed leaving only a predetermined thickness,
The uncut portion of the covering member is torn off and divided.

After the dividing process, the polarizing member is provided on the outer surface of the substrate. However, if the structure including the polarizing member is adopted as the covering member, this step can be simplified.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the present invention with reference to FIGS.

In this embodiment, L using a hard and brittle plastic substrate typified by epoxy type, acrylic type, etc.
A cell dicing process and a lead-out dicing process of the CD are performed by using a dicing device (not shown).

The dicing device is equipped with a disk-shaped dicing blade mixed with diamond particles, and the dicing blade is rotated at a high speed to divide the plastic substrate. The thickness of the dicing blade is 20 μm to 200 μm, and the rotation speed is 800.
It is 0 rpm to 40,000 rpm.

By cutting the plastic substrate by rotating the dicing blade at the above high speed, cracks do not occur on the cross section, and the substrate can be stably divided. Incidentally, not only changing the rotation speed of the dicing blade, the blade width of the dicing blade, the diameter,
By changing the conditions such as the diamond grain size and the stage feed speed for adsorbing the object to be cut, a better cross section can be obtained.

Here, the dividing process performed by using the dicing device will be described below. That is, thickness 0.4 mm
Acrylic upper / lower plastic substrates 2a / 2
b is prepared, an ITO film is vapor-deposited on these substrates 2a and 2b, and then an ITO pattern (a transparent electrode including a terminal portion) is formed by etching patterning. After that, alignment film printing, alignment treatment is performed, cell gap material is sprayed,
A sample 10 in which sticker printing is performed and the two substrates 2a and 2b are opposed to each other and bonded together is set on the stage 4 of a dicing device (Okamoto Machine Opportunity Manufacturing Co., Ltd.) (see FIG. 1). A sealing material 3 including a spacer that secures a gap for the liquid crystal layer is formed between the substrates 2a and 2b.

By the way, the dicing blade used had a thickness of 0.035 mm, a diameter of 50.2 mm, a rotation speed of 20000 rpm, and a stage feed speed of 30 mm /
It is set to sec. The cutting water usually used in the dicing machine is not used in order to prevent the penetration of water into the cell.

The method of dividing an LCD using the plastic substrate according to this embodiment under the above conditions will be described below with reference to FIGS. 1 to 8.

In the case where the above-mentioned sample 10 is subjected to the terminal dividing treatment, as shown in FIG. 1, first, the upper plastic substrate 2 is cut along the dividing marks (not shown).
A is cut by the dicing blade 1 (see FIG. 5). However, at this time, a cut is made so that only a thickness of 50 μm remains.

The upper plastic substrate 2a also has
When the ITO electrode 5 is formed, the sample 10 is turned upside down and rotated by 90 °, and the lower plastic substrate 2b is cut along the dividing marks so as to leave a thickness of 50 μm in the same manner as above. (See dashed line in FIG. 6).

The sample 10 cut as described above is then cut off from the sample 10 by being folded along the groove formed by the cut (see FIG. 2). As a result, since the upper plastic substrate 2a or the lower plastic substrate 2b is cut by the dicing blade 1 having a high rotation speed, cracks generated on the cross section can be suppressed and the ITO formed on the counter substrate can be suppressed. It is possible to prevent the electrode 5 from being damaged.

Next, in the case of subjecting the sample 10 to the cell dividing process, first, the upper plastic substrate 2a is cut by the dicing blade 1 along the dividing marks (not shown) as shown in FIG. Cut in. Then, after completely cutting the upper plastic substrate 2a, the lower plastic substrate 2b is further cut (see FIG. 5). However, at this time, a cut is made so that only a thickness of 50 μm remains. After that, the sample 10 is rotated by 90 °, and the upper and lower plastic substrates 2a and 2b are rotated in the same manner as above.
Is cut (see the alternate long and short dash line in FIG. 7).

The sample 10 cut as described above is then folded along the groove formed by the cut of the lower plastic substrate 2b,
As shown in FIGS. 4 and 8, the sample 10 is separated (breaking step).

As a result, since the upper plastic substrate 2a and the lower plastic substrate 2b are cut by the high-speed rotating dicing blade 1, it is possible to suppress cracks generated on the cross section. The lower plastic substrate 2b is left uncut during the cell dividing process in order to ensure the versatility of the stage 4 of the dicing device.

Also, the upper and lower plastic substrates 2a
By breaking 2b by a predetermined thickness, the break process can be simplified as compared with the conventional glass substrate.
Furthermore, since the cutting process can be performed after the bonding of the plastic substrates 2a and 2b, it is possible to perform the bonding press without the substrate step, as compared with the method in which the plastic substrates 2a and 2b are bonded in advance and then the cell gap is uniform. In addition to improving the property, disconnection of the electrode pattern can be prevented.

The uncut thickness of the substrate is preferably set to 50 μm or less when the substrate is made of epoxy resin or acrylic resin and has a thickness of 0.4 mm.

By the way, when the cutting process is performed by the above dicing device, the outer surface of the plastic substrate may be damaged by the cutting dust generated at the time of cutting. In order to deal with this, in the example shown here, the covering member is provided on the plastic substrate. The members having the same functions as those in the above embodiment are designated by the same reference numerals.

Also in this embodiment, similarly to the above-mentioned embodiments, the dicing device (not shown) is used to perform the cell dividing processing and the terminal dividing processing of the LCD using the plastic substrate. In addition, the cutting process is performed under the same conditions as in the above-described example except that the rotation speed of the dicing blade is 10,000 rpm.

The sample 10 is prepared, and film-shaped laminators 6 and 6 (covering members) are attached to both surfaces of the upper and lower plastic substrates 2a and 2b, respectively, and then set on the stage 4. (See FIG. 9). The material of the laminator 6 is, for example, polyethylene, and the thickness thereof is, for example, 50 μm.
It is set to m.

When the sample 10 is subjected to the terminal cutting process, the laminator 6 is first cut by the dicing blade 1 along the cutting mark (not shown) as shown in FIG. When the cutting is completed, the upper plastic substrate 2a is further cut by the dicing blade 1 (see FIG. 5).

However, at this time, the substrate 2a is cut so that a thickness of 50 μm remains.

The upper plastic substrate 2a also has
When the ITO electrode 5 is formed, the front and back of the sample 10 are inverted and then rotated by 90 °, and the laminator 6 and the lower plastic substrate 2b are left by 50 μm along the dividing marks in the same manner as above. (See the broken line in FIG. 6).

The sample 10 cut as described above is then separated from the sample 10 by being broken along the groove of the substrate formed by the cut (see FIG. 11).

As a result, it is possible to prevent scratches on the outer surface of the substrate, which may occur when the front and back of the sample 10 are reversed because the terminals are cut and divided on both sides. In addition, the upper plastic substrate 2 with the high speed dicing blade 1
Since a or the lower plastic substrate 2b is cut, it is possible to suppress cracks generated on the cross section thereof and also to prevent the ITO electrode 5 formed on the counter substrate from being damaged.

Next, in the case of subjecting the sample 10 to the cell dividing treatment, first, as shown in FIG. 12, the laminator 6 and the upper plastic substrate 2a are diced along the dividing marks (not shown). Blade 1
Cut by. Then, after the laminator 6 and the upper plastic substrate 2a are completely cut, the lower plastic substrate 2b is further cut, the lower plastic substrate 2b is completely cut, and then the laminator 6 on the back surface of the substrate 2b is further cut. However, at this time, laminator 6
Is cut to leave a thickness of 30 μm. Then, the sample 10 is rotated by 90 °, and the laminator 6 and the upper and lower plastic substrates 2a and 2 are similarly rotated as described above.
Make a cut in b (see the alternate long and short dash line in FIG. 7).

The sample 10 cut as described above is then torn off along the groove formed by the cut of the laminator 6 on the lower plastic substrate 2b side, as shown in FIG. Sample 1
It is divided from 0 (breaking step).

As a result, the laminator 6 is left uncut by a predetermined thickness, and the upper and lower plastic substrates 2a and 2b are completely cut by the dicing blade 1 having a high rotational speed, so that the occurrence of burrs on the substrate itself is prevented and separated. The level of the cross section is improved and the occurrence of cracks is suppressed.

Further, by breaking off the laminator 6 left uncut to a thickness of 30 μm, the break process can be simplified as compared with the conventional glass substrate. Furthermore, since the cutting process can be performed after the bonding of the plastic substrates 2a and 2b, it is possible to perform the bonding press without the substrate step, as compared with the method in which the plastic substrates 2a and 2b are bonded in advance and then the cell gap is uniform. In addition to improving the property, disconnection of the electrode pattern can be prevented.

Here, the polarizing member 7 is used as the covering member.
The case where (for example, a film-shaped member) is provided on the plastic substrate will be described below. The polarizing member 7 is attached to a plastic substrate with an adhesive, for example, at a predetermined polarization axis angle, and the laminator 6 is attached to the outer surface of the polarizing member for surface protection (see FIG. 14). Also, in sample 10,
The other configurations and the dividing conditions are the same as those shown in FIG. 9, and thus detailed description will be omitted here.

In the case where the above-mentioned sample 10 is subjected to the terminal dividing treatment, the upper plastic substrate 2a / the lower plastic substrate 2b is cut so as to leave a thickness of 50 μm as in the case of the above embodiment. Then, the sample 10 that has been cut is then separated from the sample 10 by being broken along the groove of the substrate formed by the cutting.

As a result, it is possible to prevent scratches on the outer surface of the polarizing member and the outer surface of the substrate, which may be caused by swarf when inverting the front and back of the sample 10 in order to carry out the terminal dividing treatment on both sides. Further, since the upper plastic substrate 2a or the lower plastic substrate 2b is cut by the dicing blade 1 having a high rotation speed, it is possible to suppress cracks generated on the cross section, and also the ITO electrode formed on the counter substrate. It is possible to avoid damaging the 5th grade.

Next, in the case of subjecting the sample 10 to the cell dividing treatment, first, as shown in FIG. 15, along the dividing mark (not shown), the upper laminator 6, the polarizing member 7, And the upper plastic substrate 2a is cut by the dicing blade 1 and completely cut, and then the lower plastic substrate 2b is cut,
After completely cutting the lower plastic substrate 2b and the lower polarizing member 7, it is further cut into the laminator 6 on the outer surface of the substrate 2b. However, at this time, the laminator 6 is cut so that the laminator 6 remains by a thickness of 30 μm. afterwards,
The sample 10 is rotated by 90 °, and the laminator 6.6 and the upper and lower plastic substrates 2a and 2b are rotated in the same manner as above.
Then, the polarization member 7 is cut (see the alternate long and short dash line in FIG. 7).

The sample 10 cut as described above is then torn off along the groove formed by the cut of the laminator 6 on the lower plastic substrate 2b side, as shown in FIG. Sample 1
It is divided from 0 (breaking step).

As a result, the lower laminator 6 is left uncut by a predetermined thickness, and the upper laminator 6 and the upper and lower polarizing members 7 and 7 are cut by the dicing blade 1 having a high rotation speed.
Also, since the upper and lower plastic substrates 2a and 2b are completely cut, the generation of burrs on the substrate itself is prevented and the level of the cross section is improved, cracks are suppressed, and the polarizing member and the substrate are cut into chips. Can prevent damage. The reason why the laminator 6 is left uncut to a predetermined thickness is to ensure the versatility of the stage 4 of the dicing device.

Further, the break process can be simplified as compared with the conventional glass substrate by cutting the laminator 6 leaving a predetermined thickness. Furthermore, since the cutting process can be performed after the bonding of the plastic substrates 2a and 2b, it is possible to perform the bonding press in a state in which there is no substrate step, as compared with the method of bonding after previously cutting.
It is possible to improve the uniformity of the cell gap and prevent disconnection of the electrode pattern.

Further, since the polarizing member 7 is also divided at the same time, the process of dividing and adhering the polarizing member 7, which is a post-process, can be simplified and the cost can be reduced.

[0059]

As described above, in the method for dividing an LCD using a plastic substrate according to the first aspect of the present invention, the blade is rotated at a predetermined number of rotations to cut the plastic substrate sandwiching the liquid crystal layer, and the predetermined After the thickness is left uncut, it is cut off by breaking.

Therefore, even if a hard and brittle plastic substrate is cut, it is possible to suppress the generation of cracks on the cut surface. In addition, when performing the terminal disconnection processing,
It is possible to avoid damaging the electrode pattern or the like on the opposing plastic substrate. Furthermore, since the cutting process can be performed after the bonding of the plastic substrates, it is possible to perform the bonding press in a state where there are no steps in the substrate as compared with the method in which the plastic substrates are divided in advance and then bonded. In addition to being able to improve, breaking of the electrode pattern can be avoided. Also, compared to the break process when using a glass substrate, the process can be greatly simplified,
It also has the effect of reducing costs.

Further, in the method for dividing an LCD using a plastic substrate according to a second aspect of the present invention, as described above, the coating member is provided on the back surface of the plastic substrate and the blade is rotated at a predetermined rotation speed to form the liquid crystal layer. This is a configuration in which the sandwiched plastic substrate is cut into pieces, and a predetermined thickness of the covering member is left uncut, and then the pieces are separated by being torn off.

Therefore, in addition to the effect of the first aspect, it is possible to prevent the surface of the polarizing member and the substrate from being damaged by the cutting chips. Further, in the case of the cell dividing treatment, since the plastic substrate is completely divided, it is possible to prevent burrs from occurring on the substrate. Furthermore, if a covering member including a polarizing member is adopted, it is possible to simplify the post-process that requires positional accuracy when pasting a polarizing member that has been cut into a regular size after the dividing process, and improve the positional accuracy. It is possible to reduce the time and cost.

Further, the present invention is not limited to being applied to acrylic and epoxy substrates, and can be applied regardless of the material and thickness of the plastic, and also to glass substrates. This effect is also played.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a terminal extension / dividing process of the present invention.

FIG. 2 is an explanatory diagram showing that the terminal lead-out / dividing processing in FIG. 1 is completed.

FIG. 3 is an explanatory diagram showing cell division processing according to the present invention.

FIG. 4 is an explanatory diagram showing that the cell division processing has been completed in FIG. 3;

FIG. 5: LC using a plastic substrate according to the present invention
It is an explanatory view showing a division procedure of D, and showing that the terminal extension division or the cell division was performed along a predetermined division line.

FIG. 6 shows the state of FIG. 5 reversed and further rotated by 90 °,
It is explanatory drawing which shows that the lead-out division was performed.

FIG. 7 is an explanatory diagram showing that cell division processing is performed in the state of FIG. 6;

FIG. 8 is an explanatory diagram showing that the state of FIG. 7 is divided by breaking or tearing.

FIG. 9 is an explanatory diagram showing that the sample when the laminator is attached to the outer surface of the substrate is set on the stage.

FIG. 10 is an explanatory diagram showing that a lead-out dividing process is performed on the sample of FIG. 9;

FIG. 11 is an explanatory diagram showing that the terminal lead-out dividing processing is performed in FIG. 10 to divide the terminal.

FIG. 12 is an explanatory diagram showing that cell division processing is performed on the sample of FIG. 9;

FIG. 13 is an explanatory diagram showing that the cell division processing has been performed in FIG.

FIG. 14 is an explanatory diagram showing that the sample in which the laminator is provided on the polarizing member in FIG. 9 is set on the stage.

15 is an explanatory diagram showing that cell division processing is performed on the sample of FIG.

[Explanation of symbols]

 1 Dicing Blade (Blade) 2a Upper Plastic Substrate 2b Lower Plastic Substrate 4 Stage 5 ITO Electrode 6 Laminator (Coating Member) 7 Polarizing Member (Coating Member) 10 Samples

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Fukuchi 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Co., Ltd. (72) Kyohei Isohata 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Yap Co., Ltd.

Claims (2)

[Claims] 1. A method of dividing an LCD using a plastic substrate which is divided by a dicing device equipped with a blade, wherein a blade is rotated at a predetermined rotation number to cut a plastic substrate sandwiching a liquid crystal layer, A method for dividing an LCD using a plastic substrate, which is characterized in that the thickness is left uncut and then the piece is cut off. 2. A method for dividing an LCD using a plastic substrate which is divided by a dicing device equipped with a blade, wherein a covering member is provided on the back surface of the plastic substrate, and the blade is rotated at a predetermined rotation speed to form a liquid crystal layer. A method of dividing an LCD using a plastic substrate, which comprises cutting the sandwiched plastic substrate, leaving a predetermined thickness of the covering member, and then tearing it off.