JP2002331493A - Dividing method for plastic sheet and plastic product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dividing method for plastic sheet and a plastic product not generating breakage and burr in a dry dividing method by a rotary cutting edge and to provide a method for manufacturing indication elements with using the same method. SOLUTION: In a method for dryly dividing sheet containing plastic as a principle component or a product including the same as a structure member by a rotary cutting edge, the sheet or the product is coated by plastic film, and then the film and/or the sheet or the product are fixed, and the sheet or the product is divided together with the film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of dividing a plastic product, a method of manufacturing a plastic substrate used for a display device, and a method of manufacturing a display element.

[0002]

2. Description of the Related Art As a method of dividing a plastic sheet, a punching method using a die or a Thomson blade, an ultrasonic method using an ultrasonically vibrating blade, a method using a slitter knife, and the like are generally used. On the other hand, in the case of a material having a large thickness and high rigidity, a dicing method in which a circular blade is rotated to perform a dividing process is widely used. In particular, when an electronic material such as a semiconductor is divided and processed, this method is often used. In the method using the rotary blade, as shown in Japanese Patent Application Laid-Open No. 9-57692, a method of blowing water or cold air to release frictional heat and cutting without changing the characteristics of the cut portion is adopted. However, cooling water cannot be used for dividing plastics, which are rigid and do not like to absorb moisture due to severe restrictions on dimensional changes, etc. The simplest method is the method of dividing into pieces. However, in this method, strong burrs are generated at the edge of the cut portion, and when processing accuracy is required, a deburring step is required.

As a product using a plastic sheet which is severely restricted in dimensional change, there is a substrate for a liquid crystal display device. In recent years, plastic substrates have gradually established themselves as substitutes for conventional glass substrates, taking advantage of their low specific gravity, impact resistance, bendability, and the like. However, since the water absorption rate is higher than glass and the dimensional change due to water absorption is large, display defects such as display unevenness and display omission are likely to occur on a substrate for a high definition display element. Therefore, in these applications, it was necessary to avoid contact of the plastic sheet with water as much as possible. A plastic liquid crystal display element is a device in which a display panel is manufactured by bonding two plastic substrates via a spacer, and a liquid crystal is injected into a space created by the spacer. I have. In order to obtain a large number of liquid crystal display elements, the display panel on which the two plastic substrates are bonded is divided at a bonded portion where a liquid crystal injection port is partially opened. For example, Japanese Patent Laid-Open No.
As disclosed in Japanese Patent No. 127472, a method using a rotary cutter (slitter knife) that rotates without being rotated by the resistance at the time of cutting has been proposed.
In order to keep the space (cell gap) created by the spacers constant and to prevent color unevenness, the plastic sheet itself must have some rigidity, and it is suitable to use a rotary blade that does not crack or chip on the split surface. I have.

[0004]

SUMMARY OF THE INVENTION The present invention provides a method of dividing a plastic sheet or a plastic product, which does not generate cracks, chips or burrs, in a method of dry dividing with a rotary blade. A method for manufacturing a display element is provided.

[0005]

Means for Solving the Problems: The present invention provides: (1) A method of dry-divided processing a sheet mainly composed of plastic or a product comprising the same by a rotary blade, wherein the sheet or the product is A method for dividing a plastic sheet or a plastic product, comprising fixing the film and / or the sheet or the product after covering the plastic film, and dividing the film and / or the sheet or the product. (2) The method according to (1), wherein the plastic film is a stretch film. (3) The thickness of the plastic film is 5 to 100 μm
m. The method for dividing a plastic sheet or plastic product according to (1) or (2), wherein (4) The method for dividing a plastic sheet or plastic product according to (1) to (3), wherein the material of the plastic film is mainly composed of polyethylene. (5) The plastic film contains at least polymethylpentene as its material.
(4) The method for dividing a plastic sheet or plastic product. (6) The method for dividing a plastic sheet or plastic product according to any one of (1) to (5), wherein the method of fixing the sheet or product is by vacuum suction. (7) The method according to any one of (1) to (5), wherein the size of the plastic film is larger than the size of the sheet or the product. (8) The method for dividing a plastic sheet or a plastic product according to (7), wherein the fixing method of the sheet or the product is to fix the sheet or the product and / or the plastic film by vacuum suction. (9) The method for dividing a plastic sheet or plastic product according to (1) to (8), wherein the rotary blade is a grindstone blade, a diamond blade, a saw blade, or a round blade. (10) The method according to any one of (1) to (9), wherein the sheet is a plastic substrate for a display element having a thickness of 1.0 mm or less and a total light transmittance of 70% or more. (11) The display panel according to (1) to (9), wherein the product includes at least two or more plastic substrates for display elements having a thickness of 1.0 mm or less and a total light transmittance of 70% or more as constituent members. Plastic sheet or plastic product splitting method. (12) A method for manufacturing a display element, which includes the division processing method according to (10) or (11) as a manufacturing process. It is.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The plastic-based sheet used in the dividing method of the present invention is not particularly limited, but a material having a storage elastic modulus of 1 GPa or more is suitable for the method of the present invention. Can be mentioned. These sheets may be mixed, dispersed, or compounded with materials such as ceramics and metals in addition to plastics. Further, the division processing method of the present invention can also be used for a product (for example, a liquid crystal display panel or the like) in which these sheets are assembled as a constituent member by a method such as bonding.

[0007] The rotary blade used in the present invention is not particularly limited as long as it can rotate itself to divide plastic by friction, and examples thereof include a grindstone blade, a diamond blade, a saw blade, and a saw shape. Round blades that do not have them can be cited. In addition, a square blade may be used as long as it is a rotating blade. Further, the present invention is a dry division processing method performed without spraying cooling water in order to avoid water absorption into plastic.

According to the present invention, a plastic film is coated in order to perform a division process without generating cracks, chips or burrs. Japanese Patent No. 205614 discloses a method in which a sheet member is covered and fixed in tension for positioning in the dicing of an electronic material or the like, and the electronic material or the like is cut from the sheet surface.
Although described in No. 6, the object to be cut is a thin plate material such as a wafer, ferrite, or ceramic which constitutes an electronic component, and its purpose is to fix and position the object.
Japanese Patent Application Laid-Open No. Hei 7-335507 also describes that in a dicing process for an electronic material, a portion that comes into contact with a rotary blade is coated, but the coating material is a wax as a bonding agent. Is merely an example. The plastic film of the present invention has a film-like shape, and preferably has a thickness of 5 to 100 μm. If the thickness is too thin, the film will wrinkle,
In some cases, the target object cannot be fixed sufficiently. On the contrary, when the thickness is too large, a large force is required to stretch the film, which is not preferable. In addition, its physical properties are that it has a certain degree of tensile elongation and tension in order to hold the plastic sheet to be divided and the product containing it as a constituent member. None is preferred. Further, those having heat resistance and slipperiness that do not cause melting adhesion, burning, etc. due to frictional heat are more preferable. The plastic film having such physical properties is not particularly limited, and examples thereof include a polyvinylidene chloride film, a polyvinyl chloride film, a polyethylene film, a polypropylene film, and a polyethylene vinyl alcohol film. The stretch film used for packaging has good adhesion to the sheet (tackiness) and is highly effective. Further, among stretch films, even if an olefin-based film is heated to a high temperature at the time of cutting, it is preferable because it does not burn or generate corrosive gas. Further, those containing at least polymethylpentene (TPX) having good heat resistance and slipperiness as a material thereof are more preferable.

The plastic film of the present invention needs to be coated at least on the portion where the rotary blade contacts, and may be attached to the object with an easily peelable adhesive. In order to also serve the purpose of fixing, it is preferable that the size is larger than the size of the object plastic sheet or the product using the same as a constituent member. A large plastic film may be placed over the object, the object may be fixed by a method of applying a slight stretching force, and the plastic film may be further fixed. For fixing the plastic film, a method using a fixing jig may be used.However, a method using vacuum suction in which a large number of holes are opened on a flat plate, and air is suctioned from these holes to fix the object or the film by suction is used. preferable. According to this method, the object and the plastic film can be fixed at the same time, and can be fixed more firmly.

The dividing process according to the present invention means not only a method of cutting at once from the plastic film side, but also a method of inverting the object, re-covering the plastic film from the opposite side and cutting from both sides, and a cut leaving a part. And then dividing the object by a method such as bending the object later.

The division processing method of the present invention can be suitably used for manufacturing a display element substrate and a display element.
As a display element substrate, the thickness is 0.1 mm to 1.0 m.
It is desirable to use a plastic sheet having a m and a total light transmittance of 70% or more. If the thickness is small, rigidity is lost, and display unevenness may occur due to non-uniformity of the cell gap. If the thickness is large, optical characteristics such as light transmittance and retardation may be deteriorated. In addition, as for a transmission type display element substrate viewed through the substrate, the total light transmittance is desirably 70% or more.

In order to manufacture a display panel using the above-mentioned plastic sheet, the plastic sheet may be divided in advance to the size of the display panel by the division processing method of the present invention and then bonded, but the productivity is improved. To achieve this, a display panel made of a plastic sheet made of a plastic sheet of a size that can be taken in large numbers, and a display panel made by bonding with a sealant such as an epoxy-based adhesive through a spacer and opening the liquid crystal injection port In general, a liquid crystal is injected into a strip-shaped panel by dividing the liquid crystal panel in a direction in which the liquid crystal element is stripped, sealing the injection port, and further forming individual liquid crystal elements.

[0013]

The following describes one embodiment of the present invention.
The present invention is not limited to the embodiments. Example 1 A display element substrate made of a 0.3 mm thick PES sheet (size ゛ = 300 × 300 mm) was passed through a spacer using an epoxy adhesive so that the thickness of the adhesive layer was about 5 μm. And cured for 1 hour with a hot air dryer at 150 ° C.
A display panel was obtained. This display panel was set on a vacuum suction table (size = 400 x 400 mm), and a 25-μm polyethylene film (size = 400 x 400 mm) was placed on the display panel and fixed by suction. In addition, whetstone blade (# 150 mesh silicon carbide abrasive,
The bonded portion was cut by a dry dicing machine set with a size (size = 80-0.5 mmt) under the conditions of a rotation speed of 10,000 prm and a feed speed of 2 m / min.

As a result of visual observation of the cut portion, no crack was generated and no delamination was observed. Further, as a result of SEM observation of the cut edge portion, it was confirmed that the generated burr height was as small as about 10 μm, and a spatula made of plastic (0.
It was confirmed that burrs could be easily removed by rubbing with a 5 mm polycarbonate plate piece).

Example 2 A display element substrate made of a PES sheet (size ゛ = 300 × 300 mm) having a thickness of 0.3 mm was provided with a spacer using an epoxy-based adhesive so that the thickness of the adhesive layer was about 5 μm. And cured with a hot air dryer at 150 ° C for 1 hour,
A display panel was obtained. The display panel was set on a vacuum suction table (size: 400 × 400 mm), and a 10 μm (TPX / olefin) laminated film (heat-resistant raff (commercial product, size: 400 × 400 mm)) was placed on the display panel and fixed by suction. Further, the bonded portion was cut by a dry dicing machine set with a circular blade (tip angle 45 #, size ゛ = φ80-1.0 mmt) at a rotation speed of 5,000 prm and a feed speed of 3 m / min.

As a result of visual observation of the cut portion, no crack was generated and no delamination was observed. In addition, as a result of SEM observation of the cut edge portion, it was confirmed that the generated burr height was as small as about 5 μm, and a plastic spatula (0.5 m
It was confirmed that the burrs could be easily removed by rubbing with a m piece of polycarbonate plate).

Example 3 A display element substrate made of a PES sheet (size ゛ = 300 × 300 mm) having a thickness of 0.3 mm was provided with a spacer using an epoxy adhesive so that the thickness of the adhesive layer was about 5 μm. And cured with a hot air dryer at 150 ° C for 1 hour,
A display panel was obtained. The display panel was set on a vacuum suction table (size: 400 × 400 mm), and a 25 μm polyethylene stretch film (a commercially available wallet packaging film, size: 400 × 400 mm) was placed on the display panel and fixed by suction. Further, the bonded portion was cut by a dry dicing machine equipped with a saw blade (number of blades = 60, size = 80-0.5 mmt) at a rotation speed of 8,000 prm and a feed speed of 5 m / min.

As a result of visual observation of the cut portion, no crack was generated and no delamination was observed. Further, as a result of SEM observation of the cut edge portion, it was confirmed that the generated burr height was as small as about 10 μm, and a spatula made of plastic (0.
It was confirmed that burrs could be easily removed by rubbing with a 5 mm polycarbonate plate piece).

COMPARATIVE EXAMPLE 1 A display element substrate made of a PES sheet (size ゛ = 300 × 300 mm) having a thickness of 0.3 mm was provided with a spacer using an epoxy adhesive so that the thickness of the adhesive layer was about 5 μm. And cured with a hot air dryer at 150 ° C for 1 hour,
A display panel was obtained. The display panel was fixed by suction on a vacuum suction table (size = 400 x 400 mm), and the rotation speed was 10,000 prm by a dry dicing machine equipped with a grindstone blade (# 150 mesh silicon carbide abrasive, size = 80-0.5 mmt). Feed speed 2
The bonded part was cut under the condition of m / min.

As a result of visual observation of the cut portion, no crack was generated and no delamination was observed. However, the occurrence of burrs is large, and as a result of SEM observation of the cut edge, it was confirmed that the height of the generated burrs was as large as about 200 μm, and was rubbed with a plastic spatula (a 0.5 mm polycarbonate plate piece). Also, it was confirmed that burrs could hardly be removed.

COMPARATIVE EXAMPLE 2 A display element substrate made of a PES sheet (size ゛ = 300 × 300 mm) having a thickness of 0.3 mm was provided with a spacer using an epoxy adhesive so that the thickness of the adhesive layer was about 5 μm. And cured with a hot air dryer at 150 ° C for 1 hour,
A display panel was obtained. This display panel was set on a punching press, covered with a 25 μm polyethylene film (size ゛ = 400 × 400 mm) from the top of the panel, and then punched into a die (with a 45 ° edge angle).
The bonded PES substrate was cut by a hydraulic punching press set with a # linear blade under the condition that the blade was lowered from above at a mold closing speed of 50 mm / min.

As a result of visual observation of the cut portion, it was confirmed that six cracks (0.5 to 3.0 mm length) and 10 delaminations occurred at a cut length of 300 mm. Further, as a result of SEM observation of the cut edge portion, it was confirmed that burrs were hardly generated.

[0023]

[Table 1]

[0024]

According to the present invention, the plastic panel for a display element can be divided without causing cracks and delamination in the dry division processing and with very little burrs. The element was an element that exhibited good display performance not inferior to a display element using a glass substrate without being affected by moisture absorption at the time of division processing. INDUSTRIAL APPLICATION This invention is suitable for division | segmentation processing of the plastic panel for display elements which became high rigidity by enlargement and refinement | fineness, and is very effective as a manufacturing method of a plastic display element.

Claims (12)

[Claims] 1. A method of dry-cutting a sheet mainly composed of plastic or a product comprising the same as a constituent member by a rotary blade, wherein the sheet or the product is coated with a plastic film, and then the film and / or the product is coated.
Alternatively, a method for dividing a plastic sheet or a plastic product, comprising fixing the sheet or the product and dividing the sheet or the product together with the film. 2. The method according to claim 1, wherein the plastic film is a stretch film. 3. The thickness of the plastic film is 5 to 3.
3. The method for dividing a plastic sheet or plastic product according to claim 1, wherein the thickness is 100 [mu] m. 4. The method of dividing a plastic sheet or plastic product according to claim 1, wherein the material of the plastic film is mainly composed of polyethylene. 5. The method for dividing a plastic sheet or plastic product according to claim 1, wherein the plastic film contains at least polymethylpentene as a material thereof. 6. The method for dividing a plastic sheet or plastic product according to claim 1, wherein the fixing method of the sheet or the product is by vacuum suction. 7. The method according to claim 1, wherein the size of the plastic film is larger than the size of the sheet or the product. 8. The fixing method of the sheet or the product,
The method according to claim 7, wherein the sheet or the product and / or the plastic film is fixed by vacuum suction. 9. The method according to claim 9, wherein the rotating blade is a grindstone blade, a diamond blade,
The method for processing a plastic sheet or a plastic product according to any one of claims 1 to 8, wherein the method is a saw blade or a round blade. 10. The plastic sheet or plastic product according to claim 1, wherein the sheet is a plastic substrate for a display element having a thickness of 1.0 mm or less and a total light transmittance of 70% or more. Division processing method. 11. The display panel according to claim 1, wherein the product comprises at least two plastic substrates for display elements having a thickness of 1.0 mm or less and a total light transmittance of 70% or more as constituent members. A method for dividing a plastic sheet or plastic product according to any one of the preceding claims. 12. A method for manufacturing a display element, comprising the division processing method according to claim 10 as a manufacturing step.