JP3091001B2 - Phosphor screen formation method - Google Patents

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 phosphor screen, and more particularly to a method for forming a phosphor screen on a cell barrier surface of a plasma display panel (hereinafter referred to as PDP).

[0002]

2. Description of the Related Art FIG. 3 shows an example of the configuration 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 and opposed to each other, and both are held at a fixed interval by a cell barrier 13 provided therebetween. An anode 14 is formed on the back side of the front plate 11 and the back plate 1
A cathode 15 is formed orthogonally to the anode 14 on the front side of 2, and a fluorescent screen 16 is formed adjacent to both sides of the anode 14.

In the above-described conventional DC-type PDP, a front panel 11 and a rear panel 12 are formed by applying a predetermined voltage from a DC power source between an anode 14 and a cathode 15 to form an electric field.
Discharge is performed inside each cell 17 as a display element composed of a cell and a cell barrier 13. The ultraviolet light generated by the discharge causes the fluorescent screen 16 on the back side of the front plate 11 to emit light, so that the light transmitted through the front plate 11 can be visually recognized by an observer.

FIG. 4 shows a configuration example of a conventional AC PDP. As shown in FIG.
In the C-type PDP, as in the case of the DC-type PDP, a flat front plate 21 and a rear plate 22 made of glass are disposed in parallel with and opposed to each other, and both are provided between them. The cell barrier 23 is maintained at a constant interval. In the AC type PDP, two electrodes 2 orthogonal to each other are provided on the front side of the back plate 22.
4 and 25 are formed via a dielectric layer 26, a dielectric layer 27 and a protective layer 28 are formed on the front side, and a fluorescent screen 29 is formed on the back side of the front plate 21. It has become.

In the above-mentioned conventional AC type PDP, a front plate 21 and a back plate 22 are formed by applying a predetermined voltage from an AC power source between two electrodes 24 and 25 to form an electric field.
Discharge is performed inside each cell 30 as a display element composed of the cell barrier 23 and the cell barrier 23. The ultraviolet light generated by the discharge causes the fluorescent screen 29 on the back side of the front plate 21 to emit light, so that the light transmitted through the front plate 21 can be visually recognized by an observer.

Here, it is well known that the shape of the cell barrier includes a matrix shape and a line shape. For example, in the case of a DC type PDP, FIG. FIG. 6 shows a line shape. In these figures, 31 is a front plate arranged on the observer side, 32 is a rear plate, 33 is a cell barrier, 34
Indicates an anode and 35 indicates a cathode. 5 and 6 show an example in which the cell barrier 33 is formed on the back plate 32 when forming the PDP, but the cell barrier 33 may be formed on the front plate 31 in some cases.

[0007] Then, as shown in FIG. 3 and FIG.
The phosphor screen in the C-type PDP or AC-type PDP is usually formed by applying a photosensitive slurry liquid containing a phosphor on the back surface of the front plate, exposing using a photomask corresponding to the pattern of the phosphor screen, and further developing, It is formed by firing. Examples of the photosensitive slurry include phosphors,
A mixture containing polyvinyl alcohol (PVA) and a diazonium salt is used, and in some cases, an antifoaming agent or a surfactant may be added.

By the way, in the PDP having the above structure, light emitted from the phosphor screen passes through the phosphor screen itself and is visually recognized by an observer, so that the amount of light decreases when transmitted through the phosphor screen. For this reason, a PDP has been proposed in which a fluorescent screen is formed on the wall surface of the cell barrier for the purpose of increasing the luminance, and the reflected light of the light emitted from the wall surface is directly viewed. As a method for obtaining such a PDP, for example, a phosphor screen forming method described in Japanese Patent Application Laid-Open No. 1-313837 is known.

The procedure of this phosphor screen forming method is shown in FIGS.
Is shown in In this method, first, as shown in FIG. 7, a phosphor slurry liquid 44 is filled in a cell barrier 43 formed so as to straddle a cathode 42 on a back plate 41, and then, as shown in FIG. The face plate 41 is set up vertically.
In this state, as shown in FIG. 9, the phosphor 44a contained in the phosphor slurry liquid 44 is allowed to stand until it has settled on the wall surface of the cell barrier 43, and then dried, so that the cell barrier 43 as shown in FIG. The phosphor 44a is attached to the wall surface.
Then, by using a negative type photosensitive liquid as the phosphor slurry liquid 44, as shown in FIG. 11, the oblique exposure is performed through the mask 45 so that only the wall surface of the cell barrier 43 is irradiated with the ultraviolet rays 46. Phosphor 44a on the wall
Can be cured, and then developed to form a phosphor screen on the wall surface. This operation is performed four times to form fluorescent screens on four surfaces of the cell barrier 43 partitioned in a matrix. This operation is performed for red (R), green (G), and blue (B) to form three primary color phosphor screens.

[0010]

However, in the above-described method for forming a phosphor screen, the phosphor slurry liquid is required to be filled up to 12 times in total and selective exposure is obliquely performed through a mask. There is a problem that it takes a long time to complete the phosphor screen because it is much complicated and takes a long time to settle the phosphor. In addition, irregularities in the height of the cell barriers are reflected during the oblique exposure process, making it difficult to stably pattern the phosphor screen. Since the thickness is less than 20 μm, there is also a problem that a fluorescent screen having a high film thickness cannot be formed.

[0011] The present invention has been made in view of the above-mentioned problems, and has been described in the art.
Another object of the present invention is to provide a phosphor screen forming method capable of accurately forming a phosphor screen having a high film thickness.

[0012]

In order to achieve the above object, a method of forming a phosphor screen according to the present invention comprises the steps of: forming a cell on a flat substrate for a plasma display having a cell barrier constituting a plurality of display element cells; In the method of forming a phosphor screen on the surface of a barrier, a cross-linking agent is applied in advance to the cell barrier at a desired concentration, and a phosphor paste containing a resin cross-linked by the cross-linking agent as a component in a predetermined cell. And developing after a predetermined crosslinking reaction time elapses to form a phosphor screen on the surface of the cell barrier.

When PVA is used as the resin, boric acid, borax, diazonium salt,
Copper compounds, aluminum compounds, titanium compounds, zirconia compounds, tin compounds and the like can be used.

Other combinations of the above resin and a crosslinking agent for the resin include polyvinylpyrrolidone and sodium salt, ammonium persulfate, sodium phosphate, methyl methacrylate and azobisisobutyronitrile, cellulose and dimethylol urea, and chloroprene. Rubber or hydrin rubber and zinc chloride, nitrile rubber and copper sulfide, acrylonitrile-butadiene copolymer and zinc chloride or tin chloride, polyacrylate and γ-aminopropyltriethoxysilane, 1
-Chlorobutadiene and an aminosilane coupling agent, trimethoxysilane-grafted polyethylene and water.

[0015]

According to the present invention, the resin in the phosphor paste filled in the cells is cross-linked and hardened in the vicinity of the surface of the cell barrier by the cross-linking agent previously applied to the cell barrier. A phosphor screen is formed on the substrate. The thickness of the phosphor screen to be formed is determined by the concentration of the cross-linking agent previously applied to the cell barrier, the resin concentration in the phosphor paste to be filled, the crosslinking reaction time from the filling of the phosphor paste to the development, and the Adjusted by strength.

[0016]

Embodiments will be described below with reference to the drawings.

Example 1 In this example, PVA224-10% aq (50 g), n-
60 g of a binder obtained by mixing butanol (5 g) and ethylene glycol (50 g) was added to 100 g of the phosphor, and
What was dispersed by this roll was used. The phosphor is (Y, Gd) BO ₃ : Eu ³⁺ as red, Zn ₂ SiO ₄ : Mn as green, and BaMgAl ₁₄ O as blue.
₂₃ : Eu ²⁺ was used. Hereinafter, this embodiment will be described with reference to FIG.

First, as shown in FIG. 1A, a Ni electrode 2 having a width of 300 μm is formed on the front side of a back plate 1 which is a glass substrate by screen printing, and then a height of 200 μm and a width of 200 μm are formed by screen printing. 150μm, pitch 500μ
The cell barrier 3 having a square matrix structure of m was formed. Then, in order to attach boric acid, a cross-linking agent for PVA, to the cell barrier surface, the cell was uniformly filled with an aqueous solution 4 of 2% boric acid as shown in FIG. At this time, 5% of ethyl alcohol is mixed with the aqueous solution 4 of 2% boric acid to facilitate uniform filling in the cell. When this is dried, the cell barrier 3 absorbs moisture, so that the cross-linking agent 4a made of boric acid is concentrated on the wall surface of the cell barrier 3 as shown in FIG.

After drying, the phosphor paste 5 is selectively filled into predetermined cells by screen printing as shown in (d), and after a crosslinking time of 10 minutes, spray hot water is applied as shown in (e). 6 to remove unnecessary phosphor paste not cross-linked in the cell, thereby obtaining a phosphor screen 5 a on the surface of the cell barrier 3. By repeating this process for R, G, and B, a phosphor screen having a thickness of 30 μm was formed only on the surface of the cell barrier 3.

Example 2 In this example, Cu ₂ SO ₄ was used as a crosslinking agent for PVA. Hereinafter, this embodiment will be described with reference to FIG.

First, 2 wt% of Cu ₂ SO ₄ is mixed and dispersed well in the printing paste for the cell barrier formed by screen printing, and then the printing paste is used to form a paste as shown in FIG. A cell barrier 7 was formed on the back plate 1 by screen printing in the same pattern as shown in Example 1. Next, as shown in (b), an aqueous solution 8 of 3% Na ₂ CO ₃ was filled in the cell as a crosslinking accelerator. When this is dried, the cell barrier 7 absorbs moisture (c).
As shown in (1), the crosslinking accelerator 8a made of Na ₂ CO ₃ adheres to the wall surface of the cell barrier 7.

After drying, as shown in (d), the same phosphor paste 5 as used in Example 1 was selectively filled in predetermined cells by screen printing. After a crosslinking time of 10 minutes after filling, as shown in (e), development is performed with hot spray water 6, and this is repeated for R, G, and B, whereby the phosphor screen 5a having a thickness of 30 μm is formed on the cell barrier. 7 could be formed only on the surface.

In the above embodiment, a PDP in which cell barriers are arranged in a matrix has been described.
The present invention can be similarly applied to a PDP in which the cell barriers are arranged in a line shape and further in a circular shape.

In the above embodiment, the filling and development of the phosphor paste were performed three times for R, G and B.
The R, G, and B phosphor pastes may be continuously filled into predetermined cells by screen printing, and the development process may be performed once.

The method of filling the phosphor paste is not limited to the screen printing described above, but may be a spraying method or a blade coating method.

[0026]

As described above, according to the method of forming a phosphor screen of the present invention, a cross-linking agent is applied to a cell barrier, and a predetermined phosphor is filled in a predetermined cell with a phosphor paste containing a resin to be cross-linked. Since only the resin near the cell barrier was cross-linked and cured to a desired thickness to form a phosphor screen,
A phosphor screen can be easily formed on the surface of a cell barrier accurately in a desired thickness in a short time. As a result, it is possible to obtain a high-brightness PDP in which reflected light can be viewed.

[Brief description of the drawings]

FIG. 1 is a process chart showing one embodiment according to a phosphor screen forming method of the present invention.

FIG. 2 is a process chart showing another embodiment according to the phosphor screen forming method of the present invention.

FIG. 3 is a partial cross-sectional view of a configuration example of a conventional DC plasma display panel.

FIG. 4 is a partial cross-sectional view of a configuration example of a conventional AC plasma display panel.

FIG. 5 is a partially cutaway perspective view showing a DC type plasma display panel in which cell barriers have a matrix shape.

FIG. 6 is a partially cutaway perspective view showing a DC type plasma display panel in which a cell barrier has a linear shape.

FIG. 7 is an explanatory view showing a first-step process according to a conventional phosphor screen forming method.

FIG. 8 is an explanatory view showing a step following FIG. 7;

FIG. 9 is an explanatory view showing a step that follows the step in FIG. 8;

FIG. 10 is an explanatory view showing a step following FIG. 9;

FIG. 11 is an explanatory diagram showing a step that follows the step of FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Back plate (substrate) 3 Cell barrier 4a Crosslinking agent 5 Phosphor paste 5a Phosphor screen

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-155142 (JP, A) JP-A-62-2427 (JP, A) JP-A-5-12999 (JP, A) JP-A-1- 313837 (JP, A) JP-A-56-48032 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 9/227 H01J 11/00 H01J 17/49 H01J 9/20

Claims (1)

(57) [Claims] 1. A method of forming a phosphor screen on a surface of a cell barrier of a planar substrate for a plasma display having a cell barrier constituting a plurality of display element cells, wherein the cell barrier is previously cross-linked to a desired concentration. An agent is applied, and a phosphor paste containing a resin cross-linked by the cross-linking agent as a component is filled in a predetermined cell, and after a predetermined cross-linking reaction time has elapsed, development is performed, and a phosphor screen is formed on the surface of the cell barrier. Forming a phosphor screen.