JPH05190094A - Method of forming fluorescent plane of plasma display panel - Google Patents

Abstract

PURPOSE:To accurately and easily form a fluorescent plane regardless of material used for a previous process. CONSTITUTION:A fluorescent plane formed on a board 1 provided with an electrode 2 and a cell barrier is previously coated with high polymer organic compound 3, and fluorescent slurry 4 is hardened and filmed in a desired pattern and then organic component and the high polymer organic compound 3 contained in a fluorescent hardened layer 6 are fired out in a firing process to form a fluorescent plane 7 at a desired position. A photolithography process to form the fluorescent plane can be done without being affected by material for the electrode 2 and the cell barrier. Accordingly, existing electrode paste and cell barrier paste can be used which are limited to be used because products and residuals brings difficulty to form the fluorescent plane.

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 fluorescent screen on a plasma display panel (hereinafter referred to as PDP) which is a self-luminous flat panel display using gas discharge.

[0002]

2. Description of the Related Art FIG. 2 shows one configuration example of a conventional DC PDP. As shown in the figure, in this DC type PDP, a flat front plate 11 made of glass is used.
The rear plate 12 and the rear plate 12 are arranged in parallel to each other and face each other, and both of them are held at a constant interval by a cell barrier 13 provided therebetween. Further, the anode 14 is formed on the back side of the front plate 11 and the back plate 1
A cathode 15 is formed on the front surface side of 2 perpendicularly to the anode 14, and a phosphor screen 16 is formed adjacent to both sides of the anode 14. In this DC type PDP, by applying a predetermined voltage from a DC power supply between the anode 14 and the cathode 15 to form an electric field, a display element composed of the front plate 11, the back plate 12 and the cell barrier 13 is formed. The discharge is performed inside each cell 17 of. Then, the fluorescent surface 16 on the back side of the front plate 11 is caused to emit light by the ultraviolet rays generated by this discharge, and the observer visually recognizes this light transmitted through the front plate 11.

FIG. 3 shows an example of the structure of a conventional AC type PDP. As shown in FIG.
In the C-type PDP, as in the case of the DC-type PDP, the flat plate-shaped front plate 21 and the rear plate 22 made of glass are arranged in parallel and opposite to each other, and both are provided between them. The cell barriers 23 are held at regular intervals. Further, in this AC type PDP, two electrodes 2 orthogonal to each other are provided on the front surface side of the back plate 22.
4, 25 are formed via a dielectric layer 26, a dielectric layer 27 and a protective layer 28 are further formed on the front side thereof, and a fluorescent screen 29 is formed on the back side of the front plate 21. Has become. In this AC type PDP, a front plate 21 is composed of a rear plate 22 and a cell barrier 23 by applying a predetermined voltage from an AC power source between two electrodes 24 and 25 to form an electric field. Each cell as
The discharge is performed inside the. Then, the fluorescent surface 29 on the back side of the front plate 21 is caused to emit light by the ultraviolet rays generated by this discharge, and the observer visually recognizes this light transmitted through the front plate 21.

Here, there are a matrix shape and a line shape as the shape of the cell barrier, for example, DC.
In the case of the type PDP, FIG. 4 shows a matrix and FIG. 5 shows a line. 4 and 5, 31 is a front plate arranged on the observer side, 32 is a rear plate, 33 is a cell barrier, 34 is an anode, and 35 is a cathode. Further, although those shown in these figures are examples in which the cell barrier 33 is formed on the back plate 32 when forming the PDP, the cell barrier 33 may be formed on the front plate 31 in some cases.

The DC type or A having the above-mentioned structure
The phosphor screen of the C-type PDP is generally formed by a photolithography method. Specifically, after applying a photosensitive phosphor slurry to the back surface of the front plate, a photomask corresponding to the pattern of the phosphor screen is used. It is formed by exposing it to light, developing it, and baking it. As the photosensitive phosphor slurry, phosphor, polyvinyl alcohol (PV
A mixture comprising A) and a diazonium compound is used,
In some cases, a defoaming agent or a surfactant may be added.

Further, in the DC type or AC type PDP as shown in FIGS. 2 and 3, the light emitted from the fluorescent screen passes through the fluorescent screen itself and is visually recognized by an observer. The amount of light will decrease during transmission. Therefore, for the purpose of increasing the brightness, a PDP is proposed in which a fluorescent screen is formed on the wall surface of the cell barrier and the reflected light of the light emitted from the fluorescent screen is directly viewed. As a forming method, for example, Japanese Patent Laid-Open No. 1-3138
There is known a method of forming a fluorescent screen across a cell barrier and a back plate by a photolithography method as shown in Japanese Patent Laid-Open No. 37.

[0007]

However, when the phosphor screen is formed by the above-mentioned photolithography method, for example, when the Ni electrode formed by thick film printing is formed on the glass substrate, the boron in the electrode paste is baked during firing. There is a problem in that the PVA-based phosphor slurry is solidified in a gel state due to boric acid generated by the oxidation of, particularly sodium borate generated by the reaction with sodium contained in the glass substrate or the paste, and accurate patterning cannot be performed. In addition, the material forming the electrodes and cell barrier is boron, copper,
When aluminum, titanium, zirconium, tin, vanadium, or chromium is contained, or when aldehydes, methylol compounds, activated vinyl groups, epoxy compounds, esters, diisocyanates, etc. remain in the electrode or cell barrier. In some cases, the phosphor slurry containing PVA as a main component is solidified at the time of application, and accurate patterning cannot be performed or a uniform film thickness cannot be secured. There was a problem that the photolithography process of (3) was hindered.

The present invention has been made to solve such a problem, and provides a method for forming a fluorescent screen of a PDP, which can accurately and easily form a fluorescent screen regardless of the material used in the previous step. The purpose is to do.

[0009]

In order to achieve the above object, the present invention provides a method for forming a fluorescent screen of a PDP having a plurality of display element cells between a front plate and a back plate, the front plate or the back plate. After forming an electrode and / or a cell barrier on a substrate to be a substrate, a surface on which a fluorescent surface is to be formed is coated with a high molecular weight organic compound, and after drying the high molecular weight organic compound, a photosensitive fluorescent substance slurry is applied thereon. After coating, the phosphor slurry is hardened in a desired pattern, and then the organic component and the high molecular weight organic compound contained in the phosphor slurry are burned off in a firing step to form a phosphor screen. To do.

[0010]

According to the above-described phosphor screen forming method of the present invention, when the phosphor screen is formed after the electrodes and cell barriers are formed on the substrate, the polymer compound is previously coated on the place where the phosphor slurry should be applied. Therefore, the photolithography process for forming the phosphor screen is performed without being affected by the materials of the electrodes and the cell barrier.

[0011]

FIG. 1 is a process chart showing an embodiment of a method for forming a phosphor screen of a PDP according to the present invention, in which a phosphor screen is formed on the same surface as an electrode formed on a front plate of a DC type PDP. Is shown. Hereinafter, each step shown in FIGS. 1A to 1F will be described step by step.

First, as shown in FIG. 1A, an anode 2 is formed in a thick film or thin film state on a substrate 1 made of ceramic such as glass. Then, the high molecular compound 3 such as ethyl cellulose, polyacrylic resin, phenol resin, melamine resin, polyester resin is dissolved in a solvent that does not dissolve a substance that inhibits the photolithography method, and this is sprayed, spinnered, A dip method, a printing method, a blade coater method, a roll coater method or the like is applied so as to cover the surface on which the fluorescent surface is to be formed on the substrate 1 as shown in (b), and dried. continue,
As shown in (c), the photosensitive phosphor slurry 4 is applied to the entire surface and dried. Then, as shown in (d), after exposing through the mask 5 having a phosphor screen pattern, development is performed as shown in (e) to remove unnecessary portions of the phosphor, and a phosphor slurry cured layer having a desired pattern is formed. 6 is formed.

Here, when the phosphors having different emission colors are separately coated, the steps of coating, exposing, and developing the phosphor slurry may be repeated for the required number of emission colors. For example, in the case of a color PDP, coating and drying of a phosphor slurry, selective exposure through a phosphor screen pattern mask for phosphors having red, green, and blue color lights, respectively.
The removal of the phosphor in the unnecessary portion and the hardening of the desired pattern portion by the development are repeated.

Finally, in the firing step, the organic components of the phosphor slurry cured layer 6 and the polymer compound 3 used for the underlying coating are substantially burned off to obtain a desired pattern as shown in FIG. 1 (f). The fluorescent screen 7 is formed.

In addition to the front plate having the fluorescent screen 7 thus formed, a back plate having a cathode and a cell barrier is formed, and a PDP is formed by combining the front plate and the back plate. It

Although the front plate of the DC type PDP has been described above, it is obvious that the same can be applied to the AC type PDP.

The phosphors which can be used in the present invention include red Y ₂ O ₃ : Eu and Y ₂ SiO ₅ : E.
_{u, Y 3 Al 5 O 12} : Eu, Zn 3 (PO 4) 2: M
n, YBO ₃ : Eu, (Y, Gd) BO ₃ : Eu, Gd
_{BO 3: Eu, ScBO 3:} Eu, LuBO 3: There is Eu or the like, Y ₂ SiO ₅ as a blue: Ce, CaWO _4:
Pb, BaMgAl ₁₄ O ₂₃ : Eu and the like, and green as Zn ₂ SiO ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, SrA.
_{l 13 O 19: Mn, CaAl} 12 O 19: Mn, YBO 3: T
b, BaMgAl ₁₄ O ₂₃ : Mn, LuBO ₃ : Tb, G
dBO ₃ : Tb, ScBO ₃ : Tb, Sr ₆ Si ₃ O ₃
Cl ₄ : Eu, etc.

Next, a specific example of the above embodiment will be described in detail below.

Ni paste (manufactured by DuPont, 9536) is screen-printed on a glass substrate to be a front plate.
In D), Ni electrodes were printed with a width of 150 μm and a pitch of 500 μm, and dried and baked to form an anode. After washing the substrate, be careful not to cover the anode and cover the entire surface with 3 wt% of ethyl cellulose (N-200, manufactured by Hercules).
The toluene solution was applied with a spinner and dried. Then, a phosphor (Zn ₂ SiO ₄ : Mn) having a green emission color, PVA (manufactured by Kuraray Co.,
224), pure water, methanol and formaldehyde condensate of P-diazophenylamine (D, manufactured by Shinko Giken Co., Ltd.
014) is coated with a phosphor slurry using a blade coater, dried at room temperature, and then exposed to UV light having a wavelength of about 350 nm through a phosphor screen mask having a desired pattern.
Exposure was performed by irradiating from the back side of the substrate with an irradiation amount of 0.0 mW / cm ² . Subsequently, this substrate was spray-developed with water to remove unnecessary portions of the phosphor slurry.
Then, the steps following the phosphor slurry application are similarly performed for a phosphor having a blue fluorescent color (BaMgAl ₁₄ O ₂₃ : Eu) and a phosphor having a red fluorescent color ((Y, Gd) BO ₃ : Eu). After repeating, the resin component (PVA), the curing agent and the masking agent (ethyl cellulose) in the phosphor slurry were burned off by baking at about 440 ° C. for 30 minutes,
Fluorescent screens, which were painted in red, green and blue in a desired pattern, were formed on the substrate except the electrodes.

By combining the front plate having the phosphor screen and the rear plate having the cathode and the cell barrier separately, a matrix color PDP in which the three primary colors of red, green and blue are visually recognized is formed. PD created in this way
In P, a phosphor screen is formed on the back side of the front plate, and this phosphor screen is excited by ultraviolet rays generated by plasma discharge to emit light, and an observer visually recognizes the transmitted light of the phosphor screen.

Needless to say, a PDP having a structure having a line-shaped cell barrier as shown in FIG. 5 can also be formed by the same process.

[0022]

As described above, according to the method of forming a phosphor screen of a plasma display panel of the present invention, the surface of the substrate on which the electrodes and cell barriers are to be formed is to be coated with a polymer organic compound in advance. In advance, after the phosphor slurry is hardened at a desired location, the organic component and the high molecular weight organic compound contained in the phosphor slurry are burned off in the firing process to form a phosphor screen at the desired location. Since the photolithography process for forming the phosphor screen is performed without being affected by the material of the electrodes or cell barriers, the film can be accurately patterned and uniform regardless of the materials forming the electrodes or cell barriers. A thick fluorescent screen can be formed. Therefore, it becomes possible to use a ready-made electrode paste or cell barrier paste, the use of which has been restricted due to difficulty in forming a fluorescent screen due to products and residues.

[Brief description of drawings]

FIG. 1 is a process chart showing an embodiment of a phosphor screen forming method of a plasma display panel according to the present invention.

FIG. 2 is a partial cross-sectional view showing an example of a DC type plasma display panel.

FIG. 3 is a partial cross-sectional view showing an example of an AC type plasma display panel.

FIG. 4 is a partially cutaway perspective view showing a DC type plasma display panel in which a cell barrier has a matrix shape, with a front plate and a rear plate thereof being separated from each other.

FIG. 5 is a partially cutaway perspective view showing a DC type plasma display panel having linear cell barriers with a front plate and a rear plate separated from each other.

[Explanation of symbols]

 1 substrate 2 electrode 3 polymer organic compound 4 phosphor slurry 7 phosphor screen

Claims (1)

[Claims] 1. A method for forming a phosphor screen of a plasma display panel comprising a plurality of display element cells between a front plate and a back plate, after forming electrodes and / or cell barriers on a substrate to be the front plate or the back plate. , The surface on which the fluorescent surface is to be formed is coated with a high molecular weight organic compound, and after the high molecular weight organic compound is dried, a photosensitive fluorescent substance slurry is applied thereon, and the fluorescent substance slurry is hardened into a desired pattern. A method for forming a phosphor screen of a plasma display panel, which comprises burning the organic components and high molecular weight organic compounds contained in the phosphor slurry by a firing step to form a phosphor screen.