JPH10273341A - Formation of ceramic rib - Google Patents

Abstract

(57) [Summary] A ceramic rib can be formed simply and accurately with a small number of steps without waste of material. An Ag-based thick film paste is applied to a portion where a rib is to be formed on a glass substrate and dried. The dried thick film paste is fired to form an Ag-based film on a portion where a rib is to be formed on the glass substrate. A conductive film 12 made of, for example, is formed. Next, the glass substrate on which the conductive film is formed and the counter electrode facing the substrate are immersed in a slurry in which ceramic powder is suspended. In the slurry, a direct current is applied to both electrodes using the conductive film on the glass substrate as an anode and the counter electrode as a cathode. A voltage is applied to electrodeposit a ceramic powder layer on the conductive film. After drying the glass substrate, the ceramic powder layer is fired to form the ceramic ribs 13. The ceramic powder is a SiO ₂ glass powder or the like,
The ceramic rib is suitable for a partition for forming a discharge cell on a glass substrate of a plasma display panel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a ceramic rib in a process of manufacturing a plasma display panel, a liquid crystal display, a fluorescent display, a hybrid integrated circuit device, and the like. More specifically, the present invention relates to a method for forming a ceramic rib serving as an insulating protective layer formed on a partition of a cell of a light emitting body or a bus electrode.

[0002]

2. Description of the Related Art Plasma display panels (plasma d)
isplay panel, hereafter referred to as PDP)
This PDP is an image display device using gas discharge, and usually has a large number of minute discharge cells arranged vertically and horizontally (in a matrix).
And characters and graphics are displayed by discharging and emitting light from necessary cells. This P
The DP has various advantages such as a simple structure, easy enlargement, a memory function, colorization, and a much larger and smaller depth than a CRT used in a television or the like. Therefore, research and development have been actively promoted in recent years.

[0003] The PDPs are classified into an AC type in which a metal electrode is covered with a glass dielectric material in terms of an electrode structure, and a DC type in which the metal electrode is exposed in a discharge space. For example, AC
As shown in FIG. 2 and FIG.
The glass plate 3 is formed over the ceramic ribs 2 formed at a predetermined interval on the glass plate 3. The surface of the glass plate 3 facing the glass substrate 1 has M
A display space 3b and a dielectric layer 3c covered with a protective film 3a of gO (magnesium oxide) or the like are formed, and a minute space 4 (FIG. 3, FIG. Hereinafter, referred to as a discharge cell)
An address electrode 4a and a phosphor 4b are formed therein. A discharge gas (not shown) is injected into the discharge cells 4.

In the PDP constructed as described above, a voltage is applied between the display electrode 3b and the address electrode 4a, and the phosphor 4b in the discharge cell 4 formed between the ceramic ribs 2 is applied.
By selectively causing discharge light emission, characters and figures can be displayed. Here, in view of the display characteristics of the PDP, in order to form the discharge cell 4 having excellent independence capable of reliably performing selective discharge light emission, it is necessary to accurately form the ceramic rib 2 having a relatively high height. It is extremely important. For this reason, as a method of forming the ceramic ribs 2, an address electrode 4a is formed on the glass substrate 1 in a predetermined pattern, and then an inorganic paste made of ceramics or glass is applied by a screen printing method and baked to have a thickness of about 70 μm. A first method for forming the ribs 2 at a height of 100 to 150 μm in width is known.

On the other hand, a sand blast method is known as a second method of forming the ceramic rib. In this method, as shown in FIG. 4, a ceramic paste containing glass powder is applied to the entire surface of the glass substrate 1 by a thick film method and dried, or by laminating a ceramic green tape containing glass powder. After forming the pattern forming layer 6 having a thickness of 150 to 200 μm,
Is coated with a photosensitive film 7, and the film 7 is further covered with a mask 8, and is exposed and developed to form a resist layer 9 having a predetermined pattern. Next, after performing a sandblasting process from above the resist layer 9 to remove a portion to be the cell 4 to form a ceramic green rib 6a, the resist layer 9 is removed using a release agent or the like, and the desired rib 2 is removed. It has gained.

[0006]

However, in the first conventional method for forming a ceramic rib, the thickness t of the rib is one.
Since the paste is relatively narrow, about 00 μm, and the paste tends to drip after printing, the height of a single coating of a thick film is 10 to
It must be kept as small as about 20 μm. As a result, in this method, in order to form a rib of 150 to 200 μm, it is necessary to apply the thick film repeatedly as many as 10 to 20 times, and the height of the rib after the upper application (≒)
h / t obtained by dividing h) by the thickness (≒ t) of the rib is 1.5 to 2
Due to the large size, there is a disadvantage that it is difficult to form ribs with high accuracy even when the alignment is sufficiently performed during thick film printing. In addition, the above-described conventional method for forming a ceramic rib requires complicated steps such as coating of a photosensitive film, exposure, and development to form a resist layer, and most of the pattern forming layer is subjected to sandblasting. There is a problem that a large amount of the material of the pattern forming layer is required for removal. An object of the present invention is to provide a method for forming a ceramic rib simply and accurately with a small number of steps and no waste of material.

[0007]

The invention according to claim 1 is
As shown in FIG. 1, a step of applying and drying an Ag-based, Au-based, Ni-based, Al-based, or RuO ₂ -based thick film paste 14 on a portion where a rib is to be formed on a glass substrate 11, and drying the thick film paste 14 is fired to form an Ag-based film, Au-based film, Ni-based film, Al-based film or R
a step of forming a conductive film 12 made of a uO ₂ -based film, a step of dipping a glass substrate 11 on which the conductive film 12 is formed and a counter electrode facing the substrate 11 in a slurry in which ceramic powder is suspended, A step of applying a DC voltage to both electrodes using the conductive film 12 on the glass substrate 11 as an anode and a counter electrode as a cathode to electrodeposit a ceramic powder layer on the conductive film 12; Baking the powder layer to form the ceramic ribs 13. This claim 1
In the method for forming a ceramic rib described in (1), a thick film paste 14 is coated on a glass substrate 11, dried and fired to form a conductive film 12, and a ceramic powder formed on the conductive film 12 by an electrodeposition method. The ceramic ribs 13 can be formed easily and accurately with a small number of steps of drying and firing the layer, and with little waste of material.

The invention according to claim 2 is the invention according to claim 1, wherein the ceramic powder is a SiO ₂ glass powder, a B ₂ O ₃ glass powder or a P ₂ O ₅ glass powder. It is characterized by. In the method for forming a ceramic rib according to the first aspect of the present invention, the adhesive strength between the conductive film and the ceramic rib is improved.

The invention according to claim 3 is the invention according to claim 1 or 2, wherein the ceramic rib is a partition wall for forming a discharge cell on a glass substrate of a PDP. According to the method for forming a ceramic rib according to the third aspect, the ceramic rib serving as a partition of the PDP can be formed easily and accurately, so that the quality of the PDP can be improved and the manufacturing cost of the PDP can be reduced.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 1B, a conductive film 12 is formed on a portion where a rib is to be formed on a glass substrate 11, and a ceramic rib 13 is formed on the conductive film 12. In this embodiment, the ceramic rib 13 is formed by P
This is a partition for forming a discharge cell on a DP glass substrate. Ag or Ag alloy, Au or Au gold alloy, Ni or Ni alloy, Al or Al alloy, or the like is used as a metal forming the conductive film 12, and RuO ₂ or the like is used as an oxide forming the conductive film 12. Used. The thickness of the conductive film 12 is preferably in the range of 0.1 μm to 20 μm, and more preferably in the range of 5 μm to 10 μm. The thickness of the conductive film 12 is 0.1 μm
The reason why the glass powder is limited to the range of 20 to 20 μm is that if it is less than 0.1 μm, it becomes difficult to uniformly adhere the glass powder.
If it exceeds 0 μm, there is a problem that the adhesion to the substrate is reduced.

The ceramic powder for forming the ceramic rib 13 is a SiO ₂ type, B ₂ O having a softening temperature of 500 ° C. or less, more preferably in the range of 450 to 490 ° C.
It is preferable to use a glass powder such as a ₃ type or a P ₂ O ₅ type. Examples of suitable glass compositions of the glass powder, the PbO 60 to 90 wt%, a SiO ₂ 10 to 30
Wt%, include those containing B ₂ O ₃ 5 to 30 wt%. The average particle size of the glass powder is preferably in the range of 1.0 to 5.0 μm, and more preferably in the range of 2.5 to 3.0 μm. In this embodiment, the ceramic rib is a partition for forming a discharge cell on a glass substrate of a PDP. However, the ceramic rib is a cell of a luminous body such as a liquid crystal display device, a fluorescent display device, and a hybrid integrated circuit device. May be an insulating protective layer on the partition wall or the bus electrode.

The ceramic rib 13 thus constructed
The method of forming the first embodiment will be described with reference to FIG. As shown in FIG. 1 (a), first, A
A g-based, Au-based, Ni-based, Al-based, or RuO ₂ -based thick film paste 14 is applied by a screen printing method and then dried. The thick film paste 14 is made of Ag or an Ag alloy having a particle size of 0.1 to 5.0 μm, Au or an Au alloy, N
i or Ni alloy, Al or Al alloy, or Ru
The metal or oxide powder O _2, 5-20 wt% SiO ₂
It is produced by adding a glass powder such as a glass powder or a B ₂ O ₃ powder and uniformly dispersing them in a solution of an organic binder and an organic solvent. Then, the dried thick film paste 14 is held at 500 to 600 ° C. in an air atmosphere for 5 to 30 minutes and baked, and the conductive film 12 is
(FIG. 1B) is formed.

Next, the glass substrate 11 on which the conductive film 12 is formed
And a counter electrode (not shown) facing the substrate 11 are immersed in a slurry in which ceramic powder is suspended. In this slurry, a DC voltage is applied to both electrodes using the conductive film on the glass substrate as an anode and the counter electrode as a cathode. Is applied to electrodeposit a ceramic powder layer (not shown) on the conductive film. As the slurry, it is preferable to use a slurry in which glass powder is dispersed in a mixed medium in which water is added to isopropyl alcohol at 2 to 4% by volume. Further, in order to improve the electrodeposition property, it is preferable to add 0.1 to 0.5% by volume of an acid to the slurry, and the concentration of the glass powder slurry is 0.02 to
Preferably it is in the range of 0.20% by weight. As the counter electrode, Al, Cu, Ni or the like is preferable, but Al is most suitable. The DC voltage applied between the conductive film and the counter electrode is preferably set in the range of 300 to 800 V, and more preferably in the range of 400 to 700 V. After the above-mentioned ceramic powder layer is formed at a desired height, the glass substrate 11 is taken out and dried, and then the glass powder in the ceramic powder layer is removed in an air atmosphere by 450 to 450 μm.
The ceramic ribs 13 are formed by firing at 600 ° C.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; <Example 1> First, as shown in FIG.
m glass substrate (soda lime glass) 11 was prepared. Then, 15% by weight was added to Ag powder having a particle size of 2.0 μm.
It was added SiO ₂ based glass powder, to prepare a thick film paste 14 by these are uniformly dispersed in a solution of ethylcellulose and α- terpineol. After applying and drying the thick film paste 14 on the glass substrate 11 so as to have a width of 100 μm by screen printing, the thick film paste 14 is held at 550 ° C. for 10 minutes in an air atmosphere and fired. An Ag conductive film 13 was formed on a glass substrate.

On the other hand, a mixed medium containing 30% by volume of isopropyl alcohol, 70% by volume of ethyl acetate, and 0.1% by volume of acetic acid was prepared. 0.2 g of SiO ₂ glass powder having an average particle diameter of 3.0 μm, a glass composition of 70% by weight of PbO, 10% by weight of SiO _{2 and} 20% by weight of B ₂ O _{3 in} this medium. (0.04% by weight) and ultrasonic waves were applied to uniformly disperse the glass powder in a mixed medium to prepare a slurry.

In the slurry, the above glass substrate and 6
A counter electrode made of an Al plate of 0 mm × 80 mm is placed and immersed such that the surface of the glass substrate 11 on which the conductive film 12 is formed and the counter electrode face each other, and the conductive film 12 is used as the anode and the counter electrode is used as the counter electrode. A DC voltage of 600 V was applied between the conductive film 12 and the counter electrode as a cathode, and a ceramic powder layer of glass powder was formed on the conductive film 12. After the electrodeposition, the glass substrate 11 and the ceramic powder layer were sufficiently dried and fired to form the ceramic ribs 13.

<Example 2> A thick film was prepared by adding 10% by weight of SiO ₂ glass powder to Au powder having a particle size of 2.0 μm and uniformly dispersing them in a solution of ethyl cellulose and α-terpineol. A paste was prepared, applied on a glass substrate and dried, and the thick film paste was dried at 560 ° C. for 10 minutes in an air atmosphere and fired on a glass substrate in the same manner as in Example 1 above. A ceramic rib was formed on the substrate.

Example 3 15% by weight of a B ₂ O ₃ glass powder was added to a Ni powder having a particle size of 2.5 μm, and these were uniformly dispersed in a solution of ethyl cellulose and α-terpineol. A thick film paste was prepared, applied to a glass substrate, and dried. The thick film paste was dried at 550 ° C. for 10 minutes in an air atmosphere and fired in the same manner as in Example 1 above. Ceramic ribs were formed on the substrate.

Example 4 A 10% by weight SiO ₂ glass powder was added to an Al powder having a particle size of 1.5 μm, and these were uniformly dispersed in a solution of ethyl cellulose and α-terpineol to form a thick film. A paste was prepared, applied on a glass substrate and dried, and the thick film paste was dried at 560 ° C. for 10 minutes in an air atmosphere and fired on a glass substrate in the same manner as in Example 1 above. A ceramic rib was formed on the substrate.

Example 5 RuO _{2 having a} particle size of 3.0 μm
20% by weight of SiO ₂ glass powder is added to the powder,
A thick film paste was prepared by uniformly dispersing these in a solution of ethyl cellulose and α-terpineol,
A ceramic rib was formed on a glass substrate in the same manner as in Example 1 except that the thick film paste applied and dried on a glass substrate was baked by holding at 560 ° C. for 10 minutes in an air atmosphere. did.

<Comparative Test and Evaluation> The application time of the DC voltage between the conductive film and the counter electrode in the electrodeposition step in Examples 1 to 5 was taken as the time until the slurry became visually transparent, and the time was measured. did. In addition, the width error, height, and unevenness of the height of the ceramic ribs on the glass substrate after firing in Examples 1 to 5 were measured.

[0022]

[Table 1]

As is clear from Table 1, the application time of the DC voltage between the conductive film and the counter electrode in the electrodeposition step of Examples 1 to 5 is relatively short, 20 to 30 minutes. It was found that ceramic ribs having a height of 147 to 155 μm could be formed. In addition, the width error and the height of the ceramic rib were also small, such as -5 to +5 μm and ± 2 to ± 3 μm, and it was found that the ceramic rib could be formed accurately.

[0024]

As described above, according to the present invention, a thick paste such as Ag is applied to a portion where a rib is to be formed on a glass substrate and dried, and the thick film paste is fired to form a glass substrate. A conductive film made of an Ag-based film or the like is formed on the upper rib forming portion, and the glass substrate and the counter electrode are immersed in a slurry in which ceramic powder is suspended. Since a ceramic powder layer was electrodeposited on the conductive film by applying a DC voltage to both electrodes using the electrode as a cathode, and further drying the glass substrate, the ceramic powder layer was fired to form ceramic ribs.
Compared with the first conventional method for forming a ceramic rib, in which a thick film needs to be repeatedly applied as many as 10 to 20 times to form a rib having a thickness of μm, the method for forming a ceramic rib of the present invention provides: Ceramic ribs can be formed easily and accurately.

In addition, a conventional second ceramic which has a problem in that a complicated process such as coating, exposure and development of a photosensitive film is required for forming a resist layer and a large amount of material for a pattern forming layer is required. Compared to the method of forming ribs,
According to the method for forming a ceramic rib of the present invention, the ceramic rib can be formed simply and accurately with a small number of steps without waste of material. If SiO ₂ glass powder, B ₂ O ₃ glass powder or P ₂ O ₅ glass powder is used as the ceramic powder, the adhesive strength between the conductive film and the ceramic rib can be improved. Further, if ceramic ribs are used as partition walls for forming discharge cells on a PDP glass substrate, PD
Since the ceramic ribs serving as partition walls for P can be formed easily and accurately, the quality of PDP can be improved and
The manufacturing cost of P can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the formation of a ceramic rib according to an embodiment of the present invention in the order of steps.

FIG. 2 is an exploded perspective view of a conventional plasma display panel including a ceramic rib.

FIG. 3 is an enlarged view of a portion A in FIG. 2;

FIG. 4 is a sectional view showing the formation of a conventional ceramic rib in the order of steps.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Glass substrate 12 Conductive film 13 Ceramic rib 14 Thick film paste

Claims (3)

[Claims] An A is formed on a portion of a glass substrate (11) where a rib is to be formed.
a step of applying and drying a g-based, Au-based, Ni-based, Al-based or RuO ₂ -based thick film paste (14); and firing the dried thick film paste (14) on the glass substrate (11). Ag-based film, Au-based film, Ni
Forming a conductive film (12) made of a base film, an Al-based film, or a RuO ₂ -based film; a glass substrate (11) on which the conductive film (12) is formed;
A step of immersing a counter electrode facing 1) in a slurry in which ceramic powder is suspended, and both electrodes in the slurry using the conductive film (12) on the glass substrate (11) as an anode and the counter electrode as a cathode. Applying a DC voltage to the electrodepositing a ceramic powder layer on the conductive film (12); and drying the glass substrate (11) and then firing the ceramic powder layer to form a ceramic rib (13). And forming a ceramic rib. 2. The method according to claim 1, wherein the ceramic powder is a SiO ₂ glass powder, a B ₂ O ₃ glass powder or a P ₂ O ₅ glass powder. 3. The method for forming a ceramic rib according to claim 1, wherein the ceramic rib is a partition for forming a discharge cell on a glass substrate of a plasma display panel.