JP2002251965A - Substrate for plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for a plasma display panel by accurately determining an actual warp and by setting the warp within a predetermined range for a good product. SOLUTION: This substrate G for a plasma display panel has the warp in the direction for projecting the film surface side, and is so structured that the warp amount thereof is 0.15% or less when it is measured based on a straightedge brought into contact over two opposite sides of the substrate G in the erected form. The actual warp is accurately determined, and the warp is set in the predetermined range for a good product, so that no space is produced when it is formed into a panel and rib breakage never occurs in transportation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a plasma display panel (hereinafter, referred to as a PDP) which is a self-luminous type flat panel display utilizing gas discharge.

[0002]

2. Description of the Related Art In general, a PDP has a structure in which a pair of electrodes arranged regularly on two opposing substrates is provided, and a gas mainly composed of Ne, Xe, He or the like is sealed between the electrodes. . Then, a voltage is applied between these electrodes, and a discharge is generated in minute cells around the electrodes, so that each cell emits light and display is performed.
In order to display information, regularly arranged cells are selectively caused to emit light. There are two types of PDPs, a direct current type (DC type) in which the electrodes are exposed to the discharge space, and an alternating current type (AC type) in which the electrodes are covered with an insulating layer. And a refresh driving method and a memory driving method.

FIG. 1 shows a configuration example of an AC type PDP. This figure shows the front plate and the rear plate separated from each other. As shown, two glass substrates 1 and 2 are arranged in parallel with each other and face each other, and both become the rear plate. Barrier ribs 3 provided in parallel with each other on the glass substrate 2 are held at regular intervals. On the back side of the glass substrate 1 serving as a front plate, a sustain electrode 4 which is a transparent electrode
A composite electrode composed of a metal electrode and a bus electrode 5 is formed in parallel with each other, a dielectric layer 6 is formed to cover the composite electrode, and a protective layer 7 (MgO layer) is further formed thereon. ing. On the front side of the glass substrate 2 serving as a back plate, address electrodes 8 are formed between the barrier ribs 3 so as to be orthogonal to the composite electrode and parallel to each other. Are formed, and the fluorescent material 1 is formed so as to cover the wall surface of the barrier rib 3 and the cell bottom surface.
0 is provided. This AC type PDP is of a surface discharge type, and has a structure in which an AC voltage is applied between composite electrodes on the front panel to discharge. Then, the phosphor 10 emits light by the ultraviolet light generated by the discharge, so that an observer can visually recognize the light transmitted through the front plate.

[0004] The back plate of the PDP is provided with an underlayer on the surface of the glass substrate 2 and then forming an address electrode 8 on the underlayer and, if necessary, covering the dielectric layer 9 with a solid film. Is formed, barrier ribs 3 are formed, and a phosphor 10 is provided between the barrier ribs 3. Further, the front plate is formed by providing a base layer on the surface of the glass substrate 1 and then holding the sustain electrode 4 and the bus electrode 5 on the base layer.
Are formed in a stack, and a dielectric layer 6 is formed so as to cover it, and a protective layer 7 is further formed. Then, the PDP is manufactured by bonding the two substrates having the respective film surfaces thus formed along the outer periphery with a sealant, and then sealing the gas.

[0005] As described above, since the front panel and the rear panel of the PDP which are separately manufactured are bonded together with a sealant on the outer periphery, it is ideal that the respective substrates have no warpage.
However, PDPs having a size of 32 to 60 inches are manufactured, and such large ones are liable to warp the substrate. Regarding the warpage of the substrate, there are various standards for each company, but as a method of measuring the warpage, as shown in FIG. 2, a substrate G is placed on a surface plate B, and a gap gauge or a dial gauge is used. In general, a method of measuring the amount of warpage using such a method is employed. Further, the direction of warpage of the substrate G allowed in this method is generally such that the film surface side of the substrate G is convex. This is because, when the respective substrates of the front plate and the back plate are warped in a concave shape, a gap is easily formed at the time of bonding.

[0006]

The conventional method for measuring the warp does not take into account the deformation of the substrate G due to gravity when the substrate size increases. That is, the substrate G
Even if there is a certain amount of warpage, when it is placed on the surface plate B, the middle part drops due to gravity as shown in FIG. 2, and the measured value by the gap gauge or dial gauge becomes smaller than the actual warp. As a result, there is a problem that the amount of warpage cannot be accurately grasped. As a result, a substrate that originally has a problem in the amount of warpage flows out as a non-defective product. Then, it has been found that the shape of a substrate having an excessively large warpage becomes complicated when the substrates are bonded together, and that ribs are easily caused by vibration or impact during transportation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to accurately grasp an actual warp and use a PDP having a warp within a predetermined range as a non-defective product. It is to provide a substrate.

[0008]

Means for Solving the Problems To achieve the above object, a PDP substrate of the present invention is a PDP substrate that is warped in a direction in which the film surface side is convex, and is used in a substrate in an upright state. It is characterized in that the amount of warpage is 0.15% or less when measured based on a straight ruler contacted over two opposing sides.

[0009]

FIG. 3 is an explanatory view showing a specific example of a method for measuring the amount of warpage. In the case of the method shown in FIG. 3, a substrate G is made up of a pair of vertical plates 11 and 12 as shown in FIG. It is set in a frame for measurement provided with a single bottom plate 13 for connecting it. Each of the vertical plates 11 and 12 has at least one or more vertical grooves 14 formed on the inner side thereof.
Two or three pedestals 15 are arranged on the bottom plate 13. The width and the shape of the grooves 14 of the vertical plates 11 and 12 are appropriately selected as long as the grooves can be vertically set by loosely fitting the substrate G.
The pedestal 15 supports the substrate G, and preferably has a cushioning property.

At the time of measurement, as shown in FIG. 3, after the substrate G is set in a frame, a straight ruler 16 is placed on the upper end edges of the vertical plates 11 and 12, and the straight ruler 16 faces the substrate G. It is in a state of contacting both sides. It should be noted that the substrate G is warped in a direction in which the film surface side becomes convex at the stage of firing in the manufacturing process. That is, the film surface is formed on the other side in FIG. And the straightedge 16
The warpage of the substrate G is measured with a gap gauge or a dial gauge on the basis of. The straight ruler 16 needs to have a straight side in contact with the substrate G in the length direction, and is preferably an aluminum square or H-shaped material in terms of workability and weight, but the material is particularly limited. Not something. Considering the substrate size of the PDP, the straight ruler 16 has a length of 140
It is easy to handle square wood and H-shaped wood of about 2 to 3 cm square at ~ 150 cm.

In the state shown in FIG. 3, the amount of warpage on the long side of the substrate G can be measured using the straight ruler 16 as a reference line. Then, by changing the height of the pedestal 15 or by turning the substrate G upside down, the amount of warpage on the long side can be measured with a plurality of reference lines. In addition, by moving the board G to another frame having a small width and setting the board G upside down, the amount of warpage on the short side of the board G can be measured.

FIG. 4 is an explanatory view showing an example of measuring the warpage of the substrate. First, in the state shown in FIG. 3, the amount of warpage of the substrate G with respect to the reference line a is measured. Next, the amount of warpage of the substrate G with respect to the reference line b is measured by setting the substrate G upside down in FIG. In addition, the substrate G is moved to a frame having a small width, and the length of the substrate G is changed, so that the warpage of the substrate G with respect to the reference line c is measured. Then, the three reference lines a, b, and c having a warpage of 0.15% or less are shipped as non-defective products.

As described above, the warpage of a substrate is measured on a plurality of reference lines, and a substrate whose measured value is within a predetermined range is regarded as a non-defective product. As a method for keeping the warpage of the substrate within 0.15%, it is natural to use a glass substrate having a small warpage from the beginning. It is desirable to adopt a method of managing

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The size is 1000 × 600 mm and the thickness is 2.
8cm glass substrate, back plate, size 1
Using a glass substrate of 050 × 550 mm and a thickness of 2.8 cm, a plurality of back plates were formed, and the amount of warpage of each substrate was measured by the method described with reference to FIG. Then, a front plate and a back plate were used in the combinations shown in Table 1, and they were attached to each other with a sealant on the outer periphery, and gas was sealed to form a panel. The PDP manufactured in this manner was transported (normal transport), and the presence or absence of rib deficiency was checked. Table 1 shows the results. The maximum value of the amount of warpage is
The largest of the two long side warpage amounts and one short side warpage amount was employed. In addition, when the rib deficiency was recognized even a little, it was marked with x.

[0015]

[Table 1]

As is clear from Table 1, when the maximum value of the warpage of each of the front plate and the rear plate is not within 1.5%, the PDP obtained by combining them is subject to vibration and impact during transportation. It can be seen that the ribs have defects.

[0017]

As described above, the PDP substrate of the present invention is a PDP substrate which is warped in a direction in which the film surface side becomes convex, and extends over two opposing sides of the substrate in an upright state. It is characterized by the fact that the amount of warpage is 0.15% or less when measured based on a straight ruler contacted with
Since the actual warpage is accurately grasped, and since the warpage is within a predetermined range as a non-defective product, no void is generated when the panel is formed, and no rib defect occurs during transportation.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a plasma display panel in which a front plate and a back plate are separated from each other.

FIG. 2 is an explanatory view showing a conventional warpage measurement method.

FIG. 3 is an explanatory diagram showing a specific example of a method for measuring the amount of warpage.

FIG. 4 is an explanatory diagram showing an example of measuring the warpage of a substrate.

[Explanation of symbols]

 1, glass substrate 3 rib 4 sustain electrode 5 bus electrode 6 dielectric layer 7 protective layer 8 address electrode 9 dielectric layer 10 phosphor 11, 12 vertical plate 13 bottom plate 14 groove 15 pedestal G substrate

Claims (1)

[Claims] 1. A substrate for a plasma display panel which is warped in a direction in which a film surface side becomes convex, and is measured based on a straight ruler which is in contact with two opposing sides of the substrate in an upright state. A substrate for a plasma display panel, wherein the amount of warpage is 0.15% or less.