JP2002175762A - Plasma display panel and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma display panel of a sealed cell structure not admitting easily the existence of gas exhaust passage, in which exhaust passage is formed in such a way as not generating such problems as increasing the number of manufacturing processes or the manufacturing cost or a problem of high aligning accuracy being required. SOLUTION: The plasma display panel is structured so that projections 32 are formed at the top of a bulkhead 30 in such a way as dotted at random between a front face base board and a back face base board so as to provide cavities due to a surface unevenness for securing the exhaust passage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma display panel and a method of manufacturing the same, and more particularly, to a structure for securing an exhaust path of a plasma display panel having a closed cell structure and a method of manufacturing the same.

[0002]

2. Description of the Related Art A plasma display panel having a closed cell structure related to the present invention is provided with a partition wall 30 having a closed cell structure called a double-girder or square type as shown in FIG. This is a plasma display panel configured to be filled with gas.

That is, the back substrate 10 comprises an address electrode or data electrode 11, a dielectric layer 12 covering the same, a grid-like partition 30 provided thereon, and a phosphor 31 covering the partition side and the dielectric layer upper surface. It is composed of

[0004] The front substrate 11 arranged opposite the rear substrate 10 has transparent electrodes (7X1, 7Y1, 7X2, 7Y).
2) and auxiliary electrodes (8X1, 8Y1, 8X2, 8Y)
2), a transparent dielectric 26 covering it, and a protective film 27 for protecting the transparent dielectric.

[0005] The plasma display panel having such a closed cell-structured partition wall has an address electrode 11 compared to a conventional stripe-shaped partition wall structure generally used.
Is characterized in that crosstalk between adjacent cells hardly occurs in the direction along. Therefore, in particular, the data electrode 11
This makes it easy to narrow the interval between cells in a direction parallel to the above, which is advantageous for higher definition.

However, when a closed cell type partition structure is used,
Since an exhaust path is unlikely to exist, Japanese Patent Application Laid-Open No. H10-149
As disclosed in Japanese Patent No. 771, there is a method of performing gas introduction and sealing in a vacuum. However, this method requires a large-scale exhaust device completely different from a general exhaust device that uses an exhaust pipe connected to a panel, so that an increase in cost cannot be avoided. In addition, there is a problem in the alignment accuracy in the vacuum chamber.

[0007]

In order to avoid the above problem, a method of separately providing a structure for securing an exhaust path on the front substrate side can be considered. That is, as shown in FIG. 9, a method of forming a band-shaped convex portion 23 on the surface of the dielectric layer 26 of the front substrate 20 so as to extend along the partition wall in either the horizontal or vertical direction. In FIG. 10, the belt-shaped convex portion 23 is
FIG. 3 is an enlarged cross-sectional view showing a state where the partition wall 30 is interposed between a top portion of an upper partition wall 30 and a front substrate 20. As the belt-like convex portions 23, it is conceivable that a transparent dielectric layer is pattern-printed or a pattern is formed with an ultraviolet-curable paste. However, such a method has problems such as an increase in the number of manufacturing steps and manufacturing costs, and a problem that high alignment accuracy is required.

[0008]

According to the plasma display panel of the present invention, in a panel having a closed cell structure in which an exhaust path is unlikely to exist, an exhaust path is provided by providing an uneven space between a front substrate and a rear substrate. It is characterized by securing.

Another feature is a method of forming unevenness for securing an exhaust path on either the top (upper surface) of the partition wall of the rear substrate or the surface of the processing surface of the front substrate. In particular, a plasma display panel having a closed cell structure is characterized by a structure in which hemispherical irregularities or undulations are provided at the tops of partition walls.

[0010] The plasma display panel of the present invention comprises:
In a panel having a closed cell structure in which an exhaust path is difficult to exist, an exhaust path can be secured by providing gaps formed by randomly scattered irregularities between the front substrate and the rear substrate, so that a conventional method is used. This has the effect that exhaust can be easily performed. Therefore, there is no problem of an increase in the number of manufacturing steps or manufacturing cost, and there is no problem such as the requirement of high alignment accuracy.

As a method of obtaining the same effect, there is a method of forming irregularities in the step of forming the transparent dielectric of the front substrate so long as the transmittance and the refractive index do not affect the panel characteristics.

In particular, according to the present invention, in a plasma display panel in which a front substrate and a rear substrate are opposed to each other with a partition constituting a closed cell structure interposed therebetween, one of the opposing regions of the front substrate and the partition is provided. In addition, a plasma display panel characterized by providing voids due to irregularities so as to secure an exhaust path is obtained.

Further, the unevenness is provided on the top of the partition wall facing the front substrate. Alternatively, the projections and depressions may be formed in a region of the front substrate facing the partition wall to form the irregularities.

Further, the unevenness is formed by providing a hemispherical convex portion on the top of the partition.

The hemispherical projection has a height of 1 to 20 μm.
m, the diameter is preferably 10 to 50 μm, and the interval between the vertices of the adjacent projections is preferably 30 to 100 μm.

Further, according to the present invention, in a method of manufacturing a plasma display panel in which a front substrate and a rear substrate are arranged to face each other with a partition forming a closed cell structure interposed therebetween, the top of the partition facing the front substrate, Alternatively, there is provided a method of manufacturing a plasma display panel, comprising a step of forming irregularities for securing an exhaust path on one of the processing surfaces of the front substrate.

[0017] In such a manufacturing method, after the partition is formed on the back substrate, a step of forming a reflective layer on the inner surface of the cell surrounded by the partition is included. In the step of forming the reflective layer, a filler is mixed. By forming the paste on the inner surface of the cell and on the top of the partition wall using the prepared paste, hemispherical irregularities are formed on the top of the partition wall.

In the step of forming the partition on the rear substrate, the partition forming material may be formed on the top of the partition by using a partition forming method such as a press method, an extrusion molding method or a roller method. A method for manufacturing a plasma display panel is also provided, wherein the unevenness is provided at the time of forming the partition by forming the partition using a mold provided with.

Further, after the partition walls are formed on the back substrate by blasting or laminating, the surface of the partition walls is subjected to blasting again to form the irregularities on the partition walls including the tops. Is also characterized.

Further, after the partition walls are formed on the rear substrate, or after a partition paste is applied, the irregularities are formed by spray coating a glass material. Is also obtained.

Further, the partition walls are formed on the rear substrate by an additive method, and at the time of the formation, a blast step is added to the paste embedded in the patterned film before the film is peeled off. Alternatively, the unevenness is formed by spray-coating a glass material.

After the transparent glaze is formed on the front substrate, the glaze paste is sprayed on the entire surface of the front substrate by spray coating or the like so that the transmittance and the refractive index do not affect the panel characteristics. It is also characterized by making.

[0023]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a structural example of a plasma display panel proposed in the present invention.

The back substrate 10 includes a data (address) electrode 11, a dielectric layer 12 covering the data electrode 11, a grid-like partition 30 provided thereon, and a phosphor 31 covering the partition side and the dielectric layer upper surface. Have been.

The front substrate 11 disposed opposite the rear substrate 10 has transparent electrodes (7X1, 7Y1, 7X2, 7Y).
2) and auxiliary electrodes (8X1, 8Y1, 8X2, 8Y)
2), a transparent dielectric 26 covering it, and a protective film 27 for protecting the transparent dielectric.

According to the first embodiment of the present invention, as shown in the figure, a large number of hemispherical projections 32 are randomly provided on the top of the cross-girder partition wall 30 on the side facing the front substrate 20. Thereby, an exhaust path is ensured. Note that the exhaust pipe connected to the panel is not shown in the drawings because it has a conventionally well-known configuration.

FIG. 2A is an enlarged view showing the formation of the projections 32 provided on the upper surface of the partition 30. As shown in FIG. 2B, by providing a gap between the partition 30 formed on the rear substrate 10 and the front substrate 20 by unevenness, the exhaust path 203 can be secured.

Each projection 32 has a height of 1 to 20 μm (preferably 5 to 15 μm) and a size (diameter) of 10 to 50 μm.
(However, the height is twice or more the height), and the interval between the vertices of the adjacent convex portions 32 is 30 to 100 μm.

As described above, according to the present invention, an exhaust path can be ensured even in a panel having a closed cell structure where an exhaust path is unlikely to exist.

A technique for forming irregularities on the partition walls is disclosed in Japanese Patent Application Laid-Open No. H11-219658, but this is merely a technique for exposing hard particles to the side faces of the partition walls to form irregularities. That is, in the publication, the purpose is to increase the surface area of the phosphor, and to increase the emission area,
This is a technique for forming unevenness only on the side surface of the partition, and there is no disclosure or suggestion of forming unevenness on the top of the partition.

Next, a first embodiment of a method for manufacturing a plasma display panel according to the present invention will be described with reference to FIG. In FIG. 1, the data electrode 11 formed on the back substrate 10 and the dielectric layer 12 covering the data electrode 11 are not shown. Hereinafter, a substrate provided with these will be described as a back substrate 10.

As shown in FIG. 3A, a grid-shaped partition 30 is formed on the rear substrate 10. The partition wall 30 is formed by using a sand blast method, which is a general partition forming step, or an additive method, which is one of the general partition forming steps. As the partition material,
A mixture of ceramic or glass powder and a binder is used.

After the formation of the partition 30, a white pigment layer 33 such as titanium oxide (titania) is formed on the upper and side surfaces of the partition 30 before the phosphor is applied, as shown in FIG. This prevents the phosphor from penetrating into the porous partition walls 30 to lower the luminance, and furthermore, functions as the reflective layer 33. This method itself is a known method disclosed in Japanese Patent No. 2773393.

Next, as shown in FIG. 3 (c), the phosphor 31 is formed by normal pattern printing or dispenser application.
To form

In the present invention, in the step of forming the reflective layer 33, a spherical filler having a particle size of 1 to 30 μm, more preferably 5 to 15 μm is added to the reflective layer material in a weight ratio of 0. 1-30%, more preferably 1-20
Mix%.

As the filler, for example, colorless transparent or white such as Al ₂ O ₃ (alumina) and ZrO ₂ (zirconia);
More preferably, a white oxide is preferable because the function of the reflective layer 33 is not impaired. This powder is made into a paste using a vehicle, and is printed on the entire surface (solid), that is, also on the top of the partition wall 30. Thus, a large number of hemispherical irregularities can be naturally formed in a form in which the reflective layer material is aggregated to some extent on the partition walls.

Therefore, when a panel is formed, a gap is formed between the front substrate and the rear substrate, so that an exhaust path can be secured (automatically). Can be exhausted.

For example, when titania is used for the reflection layer 33, the gap between the front substrate 10 and the top of the partition wall, that is, the height of the unevenness is 1 to 20 μm, preferably 10 to 15 μm.
μm. When the thickness is 20 μm or more, there is a high possibility that interference between adjacent cells will occur during driving. 1 μm
Below, the effect as an exhaust path cannot be expected.

The diameter of the projection is 10 to 50 μm, which is twice or more the height. The interval between the protrusions is 30 to 100 μm, but the protrusions do not overlap. If it is 30 μm or less, the interval between the convex portions becomes narrow, and a sufficient exhaust path cannot be secured. Also 100μ
If m or more, the number of support points between the front substrate and the partition wall decreases, and the possibility of cracks or the like due to stress concentration increases.

By the way, the interval between the projections is almost determined by the content of the filler in the paste under sufficiently stirred conditions, and the content is 0.1% by weight relative to the material of the reflective layer.
By setting the thickness to 30%, more preferably 1% to 20%, the interval between the above-mentioned convex portions can be secured. Further, it is desirable that the unevenness is constituted by a spherical surface. This is because, in the unevenness including a plane, a portion corresponding to a corner exists, and when the corner becomes a support point, stress concentration increases, and the possibility of cracks and the like increases.

In the above embodiment, as a means for forming irregularities on the top of the partition wall, a filler-containing reflection layer (titania layer) is used.
Is shown by a solid printing method, but the unevenness can be formed on the top of the partition wall by other methods described below.

An embodiment of the second manufacturing method of the present invention will be described with reference to FIG. As shown in FIG. 4A, a partition wall material layer 304 is formed on the rear substrate 10, and a press die 41 having a cross-shaped groove is pressed thereon.
By releasing the press die 41 as shown in FIG.
This method employs a so-called press molding method in which a partition wall 324 is left on the bottom surface 0, and as shown in FIG.
Is formed, the partition walls are formed by the press molding method, and at the same time, irregularities (not shown) are formed on the tops of the partition walls 324.

An embodiment of the third manufacturing method of the present invention will be described with reference to FIG. As shown in FIGS. 5 (a) and 5 (b), a mold 51 in which a partition material 305 is filled in a cross-shaped groove is pressed against the rear substrate 10, and only the partition material is transferred to the rear substrate 10. The partition 325 can also be formed by a so-called die extrusion method. At this time, by providing a hemispherical concave portion (recess) as shown in FIG. 7 on the bottom surface of the groove of the molding die 51, irregularities (not shown) are formed on the top of the partition 325 simultaneously with the transfer.

As a method of forming the irregularities on the top of the partition simultaneously with the formation of the partition, a roller method can be employed in addition to the above. That is, an embodiment of the fourth manufacturing method of the present invention will be described with reference to FIG. As shown in FIG.
In this method, a partition material layer 306 is formed on the surface of No. 0, and a roller-type forming die 61 having a cross-shaped groove corresponding to the partition is formed on the surface thereof, and is rotated and moved. By forming a concave portion corresponding to the convex portion to be formed on the top of the partition on the bottom surface of the cross-girder groove, unevenness can be formed on the top of the partition simultaneously with the formation of the partition (see FIG. 7).

As a method for forming the partition walls, there is a sand blasting method which is a general partitioning step at present, in addition to the above-described method using the mold. Referring to FIG. 8, an embodiment according to a fifth manufacturing method of the present invention in this sandblasting method will be described below.

As shown in FIG. 8A, a barrier rib material layer 308 is formed on the rear substrate 10, and a dry film resist (DFR) mask 83 for blasting is formed thereon. The entire surface is scanned using FIG.
A partition 318 is formed as shown in FIG. This partition 3
After peeling off the DFR mask 83 remaining on the top of 18,
As shown in FIG. 8C, as an additional step, the top of the partition wall 318 is subjected to blast processing for a short time by using the sand blasting machine 81 again, so that the unevenness of the partition wall 328 is reduced. It can be formed on the top (unevenness is not shown).

In place of the solid printing method for the reflective layer in the example described in the first embodiment, a spray coating method is used.
Fine projections can also be formed on the top of the partition wall by spraying a very thin glass material or a reflective layer material over the entire surface. In this method, irregularities are formed on the side wall and the bottom of the partition wall, and the effect of increasing the surface area of the phosphor can be expected. In addition, in the step of performing this spraying, when the partition is formed by a sandblasting step,
This is possible even after the partition wall paste is applied and dried.

In addition, in the additive method, which is one of the general partitioning steps, after embedding the partitioning paste in a patterned dry film, a sand blasting process is performed for a very short time before the film is peeled off. By performing any of the above-described spray coating methods, fine irregularities can be formed in a portion corresponding to the top of the partition wall.

This method can be applied to the formation of a black matrix or a black stripe on the front substrate side. By forming fine irregularities on the top of the black matrix or the black stripe,
An exhaust path can be secured.

The present invention can also be applied to a method of forming irregularities on the inner surface of the front substrate. In the case of forming irregularities on the front substrate side, after forming a transparent dielectric layer such as a transparent glaze covering the electrodes on the front substrate, a very thin glass material (glaze paste) is sprayed over the entire surface with a spray coat or the like, so that fine projections are formed. make. If a glass material having a sufficiently high transmittance (for example, SiO ₂ glass having a visible light transmittance of 90% or more at a film thickness of 100 μm) is used,
Irregularities of 20 μm or less required for the exhaust path do not significantly affect the visibility of the panel.

[0052]

According to the plasma display panel of the present invention, in a panel having a closed cell structure in which an exhaust path is unlikely to exist, an air gap formed by randomly scattered irregularities between a front substrate and a rear substrate is provided. Therefore, there is an effect that the air can be easily exhausted by using a conventional general sealing and exhausting method. Therefore, there is no problem of an increase in the number of manufacturing steps and manufacturing cost, and there is no problem that a higher alignment accuracy is required.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of a plasma display panel according to the present invention.

FIG. 2A is an enlarged perspective view showing a state of a projection provided on the top of a partition wall according to the present invention. FIG. 3B is an enlarged cross-sectional view illustrating a configuration of forming an exhaust path by the protrusions of the present invention.

FIG. 3 is a manufacturing process diagram illustrating a first manufacturing method example of the present invention.

FIG. 4 is a manufacturing process diagram illustrating a second manufacturing method example of the present invention.

FIG. 5 is a manufacturing process diagram illustrating a third manufacturing method example of the present invention.

FIG. 6 is a perspective view illustrating a fourth example of the manufacturing method of the present invention.

FIG. 7 is a perspective view showing a configuration of a bottom portion of a girder-shaped groove applied to the second to fourth manufacturing methods of the present invention.

FIG. 8 is a manufacturing process diagram illustrating a fifth manufacturing method example of the present invention.

FIG. 9 is an exploded perspective view showing an example of a conventional plasma display panel.

FIG. 10 is an enlarged cross-sectional view showing an arrangement configuration of the band-shaped convex portions 23 in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Back substrate 11 Data electrode 12 Dielectric layer 20 Front substrate 23 Belt-shaped convex part 26 Dielectric layer 27 Protective film 30 Partition wall 31 Phosphor 32 Convex part 33 Reflective layer 41 Press mold 51 Mold 61 Roller mold 71 Cross groove 71 81 Sandblasting machine 83 Mask 7X1, 7X2, 7Y1, 7Y2 Transparent electrode 8X1, 8X2, 8Y1, 8Y2 Auxiliary electrode 203 Exhaust path 304, 306, 308 Partition material layer 305 Partition material 318, 324, 325, 328 Partition

Claims (12)

[Claims] 1. A plasma display panel having a front substrate and a rear substrate opposed to each other with a partition constituting a closed cell structure interposed therebetween, wherein an exhaust path is provided in one of the opposing regions of the front substrate and the partition. A plasma display panel characterized by providing voids by irregularities so as to secure them. 2. The plasma display panel according to claim 1, wherein the unevenness is provided at a top of the partition wall facing the front substrate. 3. The plasma display panel according to claim 2, wherein the unevenness is formed by providing a hemispherical convex portion on the top of the partition. 4. The height of the hemispherical convex portion is 1 to 20 μm,
The diameter is 10 to 50 μm, and the distance between the vertices of adjacent protrusions is 3
4. The plasma display panel according to claim 3, wherein the thickness is 0 to 100 [mu] m. 5. The plasma display panel according to claim 1, wherein the projections are formed in a region of the front substrate facing the partition to form the projections and depressions. 6. A method of manufacturing a plasma display panel in which a front substrate and a rear substrate are arranged to face each other with a partition constituting a closed cell structure interposed therebetween, wherein the top of the partition facing the front substrate or a processing surface of the front substrate. A method for manufacturing a plasma display panel, comprising a step of forming irregularities on one of the surfaces to secure an exhaust path. 7. The method according to claim 7, further comprising: after forming the barrier ribs on the rear substrate, forming a reflective layer on the inner surface of the cell surrounded by the barrier ribs. 7. The method of manufacturing a plasma display panel according to claim 6, wherein the paste is formed on the inner surface of the cell and the top of the partition to form hemispherical irregularities on the top of the partition. 8. The step of forming the partition on the rear substrate, using a partition forming method such as a press type, an extrusion molding method, or a roller type, wherein the material for forming the partition is applied to a location on the top of the partition. The method for manufacturing a plasma display panel according to claim 6, wherein the unevenness is provided at the time of forming the partition by forming the partition using a mold provided with the component. 9. After forming the partition on the rear substrate by blasting or laminating, the surface of the partition is subjected to blasting again to form the irregularities on the partition including the top. The method for manufacturing a plasma display panel according to claim 6, wherein: 10. The unevenness is formed by forming the partition on the rear substrate or applying a partition paste and then spray coating a glass material. Of manufacturing a plasma display panel. 11. The method according to claim 11, wherein the partition walls are formed on the rear substrate by an additive method, and a blast step is added to the paste embedded in the patterned film before the film is peeled off. 7. The method according to claim 6, wherein the unevenness is formed by spray coating a glass material. 12. After the transparent glaze is formed on the front substrate, the glaze paste is sprayed on the entire surface of the front substrate by spray coating or the like so that the transmittance and the refractive index do not affect panel characteristics. 7. The method of manufacturing a plasma display panel according to claim 6, wherein: