JP2001035391A - Metal barrier rib for gas discharge type display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide sufficient insulating performance and high opening ratio by setting porosity of an inorganic insulating layer for covering a rib to a specific value or less, when looking at an almost lattice-shaped rib of a metal barrier rib in a vertical cross section. SOLUTION: Porosity of an inorganic insulating layer for covering a rib is set to 3% or less. The rib 1 for forming and partitioning a discharge space is formed between a through-hole 2 and a through-hole being the discharge space to become a metal isolating base board 3. The inorganic insulating layer is formed on the metal isolating base board 3 to form a metallic barrier rib. In a vertical cross section of an almost lattice-shaped rib of the metallic barrier rib, the inorganic insulating layer is formed on a surface of the rib 1 so as to cover the rib 1, and voids exist in the layer. The inorganic insulating layer having low porosity is formed by using an electrodeposition method, a dipping method, a spray method or an electrostatic painting method, and desirably a metallic base material surface is cleaned to restrain generation of gases through the reaction of glass and the impurities of a metallic base board surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a metal partition for a gas discharge type display panel.

[0002]

2. Description of the Related Art In general, a gas discharge type display panel requires an insulating partition for forming and partitioning a discharge space, and the structure of the partition generally has a substantially lattice shape (stripe cell shape). ing. Conventionally, among gas discharge type display panels, for example, in a plasma display panel, this partition is made of glass containing lead oxide and is manufactured by multilayer printing of a glass paste or further by sandblasting. Since the method is complicated, the cost increases. In addition, the manufactured partition walls and the glass removed by the sandblasting method contain a lot of harmful lead, and are not environmentally preferable.

Further, in order to improve the brightness of the plasma display panel, it is necessary to reduce the width of the partition wall and increase the aperture ratio. However, the conventional glass partition wall is fragile and difficult to reduce the width. In order to increase the definition of the display panel, it is desired to change the partition structure from a stripe cell structure to a single cell shape. However, similarly to the above, there is a problem that the processing of the glass partition is difficult and not practical. In order to solve the above-mentioned problem, Japanese Patent Laid-Open No.
Japanese Patent Application No. 05738 discloses that a metal partition having a dielectric containing glass formed on the surface is used as a partition, but has not been put to practical use in a gas discharge display panel such as a plasma display at present.

[0004]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies on the concrete method of insulating metal partition walls described in the above-mentioned Japanese Patent Application Laid-Open No. Hei 3-205538, and as a result, it has been found that the method for forming the metal partition walls has been developed. It was confirmed that there were many voids in the glass contained in the inorganic insulating layer. Then, the present inventors have studied the relationship between the porosity and the dielectric breakdown voltage, and as a result, have found that a good insulating property can be obtained below a certain porosity. Furthermore, it was also found out that the insulating properties of the inorganic insulating layer having a large void ratio exceeding 5 μm and having a large porosity were extremely deteriorated.

[0005] Furthermore, when the porosity is large, or when there is an even larger void, the thickness of the inorganic insulating layer must be increased in order to satisfy the insulating property. In addition to lowering the aperture ratio, if there are many voids, the adhesion between the metal substrate and the inorganic insulating layer will also be reduced. For this reason, it is necessary to reduce the porosity and more desirably eliminate large voids of 5 μm or more in order to make a gas discharge type display panel using a metal partition wall a practical minimum. An object of the present invention is to provide a metal partition wall for a gas discharge type display panel having sufficient insulation and a high aperture ratio in order to provide a high performance, highly reliable gas discharge type display panel. is there.

[0006]

Means for Solving the Problems The present invention has been made in view of the above-mentioned problems, and as a result of earnestly examining the relationship between the porosity of voids present in an inorganic insulating layer and the insulating property,
The present invention has been reached. That is, the present invention is a metal partition wall for a gas discharge type display panel in which an inorganic insulating layer is formed on a surface of a metal base material in which a large number of through holes are formed and ribs are formed in a substantially lattice shape. A metal partition wall for a gas discharge type display panel, wherein a porosity of an inorganic insulating layer covering the rib is 3% or less when a substantially lattice-shaped rib of the metal partition wall for a type display panel is viewed in a vertical cross section. Preferably, the metal substrate is Ni:
This is a metal partition wall for a gas discharge type display panel made of an Fe-Ni-based alloy thin plate containing 33 to 56%.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, an important feature of the present invention is that when a substantially grid-like rib of a metal partition wall for a gas discharge type display panel is viewed in a vertical cross section, a gap of an inorganic insulating layer covering the rib is provided. The rate is below a certain rate. First, the shape of a metal partition wall for a gas discharge type display panel is, for example, a substantially lattice shape in which a large number of through holes (2) are formed as shown in FIG. The substantially lattice shape is not limited to the shape shown in FIG. 1, but may be a structure in which the position and the size of the through hole (2) are intentionally changed. In FIG. 1, a rib (1) for forming and partitioning a discharge space is formed between the through-hole (2) serving as a discharge space and the through-hole, and serves as a metal partition board substrate (3). An inorganic insulating layer (4) is formed on the metal partition substrate, and becomes a metal partition (6) as shown in FIG. The vertical cross section of the substantially lattice-shaped rib of the metal partition is shown in FIG.
As shown in (1), an inorganic insulating layer (4) is formed on the surface of the rib (1) so as to cover the rib (1), and a void (5) exists in the inorganic insulating layer.

When the presence of the voids exceeds 3% of the inorganic insulating layer covering the ribs when viewed in a vertical cross section of the substantially lattice-shaped ribs, as described above, the aperture ratio is reduced and the metal base is reduced. In order to reduce the adhesion between the material and the inorganic insulating layer, the porosity of the inorganic insulating layer needs to be suppressed to 3% or less in the present invention. The preferred porosity is 2.5%, more preferably 2%.
% Or less. Further, the porosity referred to in the present invention is obtained by measuring the vertical cross section of the substantially lattice-shaped rib of the metal partition wall by, for example, an electron microscope.
With respect to the voids that can be observed at a magnification of about 00 and can be recognized using an image analyzer, the ratio of the voids to the inorganic insulating layer in the visual field is expressed as a percentage. At this time, it is preferable that the visual field of observation is selected so as to include an edge portion where the discharge is concentrated on the metal partition wall and a thinnest portion where the dielectric breakdown easily occurs.

In order to obtain an inorganic insulating layer having a low porosity, an electrodeposition method, a dipping method, a spraying method, or an electrostatic coating method may be used. Since gas generation due to the reaction between the glass forming the glass and impurities on the surface of the metal base material can be considered, the porosity can be suppressed by cleaning the surface of the metal base material. Furthermore, firing in an inert gas atmosphere is also effective.

Next, the metal partition covered with the inorganic insulating layer is used by being sandwiched between the front plate and the back plate. Since these components undergo a thermal cycle in the panel assembly process, if the thermal expansion difference is large, thermal stress is generated, and the panel is damaged and cannot function as an image display device. In order to prevent this, it is necessary for the partition to approximate the thermal expansion coefficient of the front plate and the rear plate. At present, among gas discharge panels, for example, soda-lime glass having a thermal expansion coefficient of 8.3 × 10 ⁻⁶ / ° C. is used for front and back glass of a plasma display panel. Is preferably used in the range of 33 to 56%. Fe-Ni alloys are suitable for metal barriers because their thermal expansion coefficients can be approximated to soda-lime glass and fine patterns can be easily formed by etching.

It is particularly desirable that, as disclosed in Japanese Patent Application No. 10-72242 proposed by the present inventor, N by weight%.
i: 43 to 56%, C ≦ 0.015%, Mn ≦ 0.
60%, Si ≦ 0.20%, P ≦ 0.004%, S ≦
0.004%, B ≦ 0.003%, O ≦ 0.005%,
One containing a component of N ≦ 0.005% or N
i: 43 to 56%, and a material having a (200) crystal orientation degree of 60% or more is preferably selected as a material. Also,
The inorganic insulating layer covering the metal substrate also has a similar thermal expansion coefficient, and it is preferable to use glass or the like that softens at 600 ° C. or lower. For example, Bi-B-Si-O-based or Zn
There is a -B-Si-O-based low softening point glass.

[0012]

The present invention will be described in more detail with reference to the following examples. The thermal expansion coefficient of the metal substrate is 8.3 × 10 ⁻⁶ / ° C.
Using an Fe-48% Ni alloy of the above, the shape of a partition for a plasma display, which is one of the image display devices, was processed by an etching method to form a shape as shown in FIG. 1 to obtain a metal partition substrate. Next, the metal partition wall substrate was coated with an inorganic insulating layer by an electrostatic coating method under the conditions shown in Table 1 to obtain a metal partition wall as shown in FIG. In the electrostatic coating method, a powder was charged, applied to a metal partition wall substrate, and then fired to form an inorganic insulating layer. As the powder, a Zn-B-Si-O-based low softening glass having a thermal expansion coefficient of 8.3 × 10 ⁻⁶ / ° C. and a softening point of 585 ° C. and Al ₂ O ₃ as a filler were used. The thickness of the inorganic insulating layer is 10
μm. In addition, as a pretreatment of the metal partition wall substrate, a degreasing and pickling treatment was performed.

Next, an evaluation method will be described. The porosity of the rib cross section was observed at 2000 times using an electron microscope so that the edge portion was included in the visual field, and was defined as the percentage of the ratio of the void to the inorganic insulating layer in the visual field. At this time, the number of visual fields observed was 10 in total, and the average is shown in Table 1. The insulation property is measured by measuring the dielectric breakdown voltage according to JIS-C2110.

[0014]

[Table 1]

According to the results shown in Table 1, in Comparative Material No. 4, the pretreatment of the metal substrate was not performed, and the firing temperature was just above the softening point and the firing time was short. It was observed that the number was very large and the void size of the void portion was as large as 5 μm or more. Therefore, the dielectric breakdown voltage is also extremely low. In Comparative Material No. 5, bubbles were generated due to remarkable oxidation of the metal base material, the porosity was 8%, and the insulation was low.

On the other hand, in Nos. 1 to 3 of the present invention, the porosity is 3% or less, a dielectric breakdown voltage of 2000 V or more is obtained, and sufficient insulation is secured. In addition, in No. 1 to No. 3 of the present invention, a large void exceeding 5 μm could not be observed. No. 1 of this invention
The use of the No. 3 to No. 3 metal barrier makes it possible to reduce the film thickness to 10 μm or less, which is also effective in improving the aperture ratio.
As described above, when the porosity of the inorganic insulating layer was 3% or less, it was confirmed that the inorganic insulating layer had good insulating properties.

[0017]

According to the present invention, sufficient insulation is provided,
In addition, a metal partition having a high aperture ratio can be obtained, and a high-performance and highly reliable image display device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view of a metal partition substrate used for a gas discharge type display panel.

FIG. 2 is a schematic diagram of a vertical cross section of a substantially lattice-shaped rib of a metal partition.

[Explanation of symbols]

1. Rib, 2. 2. through-hole; 3. metal partition substrate; 4. inorganic insulating layer; 5. voids; Metal bulkhead

Claims (2)

[Claims] 1. A metal partition wall for a gas discharge type display panel, comprising a metal substrate having a large number of through holes formed therein and a substantially lattice-shaped rib formed on a surface of a metal substrate, wherein the gas discharge type display panel has a gas barrier. A metal partition wall for a gas discharge type display panel, wherein a porosity of an inorganic insulating layer covering the rib is 3% or less when a substantially lattice-shaped rib of the metal partition wall for a display panel is viewed in a vertical cross section. 2. Ni: 33 to 56% by weight of a metal substrate.
The metal partition wall for a gas discharge display panel according to claim 1, wherein the metal partition wall is made of an Fe-Ni-based alloy thin plate containing: