JP2000228145A - Method for forming phosphor layer on back plate for plasma display panel - Google Patents

Abstract

(57) Abstract: A phosphor layer on a back plate for a plasma display panel capable of forming a phosphor-forming composition stably and accurately between barriers at predetermined positions on the back plate. Is provided. SOLUTION: When necessary, pressure is applied to the phosphor-forming composition in the discharge means, and an opening is applied. If necessary, pressure is applied to the phosphor-forming composition in the discharge means, and the phosphor-forming composition is applied to the opening. A meniscus is formed, and if necessary, a pulse voltage of a first predetermined voltage value is applied between the opening of the discharge means and the back plate through the electrode, and the phosphor-forming composition is applied to the opening. In a state where an elongated portion is formed by extending the meniscus vertically, the composition for forming a phosphor is made to flow down from a tip of the elongated portion to a barrier of the back plate, and a back plate for a plasma display panel and discharge means are provided. The phosphor-forming composition is filled between the barriers of the back plate while relatively moving in the direction along the barrier of the back plate, and the filling of the phosphor-forming composition between the barriers of the back plate is performed. Prior to the extension, And controlling the position to a predetermined position between the barriers.

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 layer on a back plate for a plasma display panel, and more particularly, to a method for discharging a phosphor composition comprising a high-viscosity material of 1000 cps to 1,000,000 cps and discharging the same. The present invention relates to a method of forming a phosphor layer in which a phosphor layer is formed between barriers and on side surfaces of the barrier by performing a dry heat treatment as necessary.

[0002]

2. Description of the Related Art In recent years, plasma display panels (hereinafter, also referred to as PDPs) have been used in various display devices because of their small depth, light weight, clear display, and wide viewing angle compared to liquid crystal panels. It is being used.
Generally, a plasma display panel (PDP) has two
A pair of regularly arranged electrodes are provided on a pair of opposed glass substrates, and a gas mainly containing neon, xenon, or the like is sealed between the pair of electrodes. Then, a voltage is applied between these electrodes, and a discharge is generated in minute cells around the electrodes, so that each cell emits light and display is performed. In particular, in order to display information, regularly arranged cells are selectively discharged to emit light.

Here, the structure of a PDP is shown in FIG.
An example of a C-type PDP will be described. FIG. 16 shows PD
Although it is a perspective view of the P configuration, the front plate (glass substrate 610) and the back plate (glass substrate 620) are shown apart from actuality for easy understanding. As shown in FIG. 16, two glass substrates 610 and 620 are arranged in parallel and opposed to each other, and both are glass substrates 620 serving as a back plate.
Barriers provided parallel to each other (also called cell barriers)
By 630, it is held at regular intervals. On the back side of the glass substrate 610 serving as a front plate, composite electrodes composed of a transparent electrode 640 serving as a sustain electrode and a metal electrode 650 serving as a bus electrode are formed in parallel with each other. A layer 660 is formed, and a protective layer (MgO layer) 670 is further formed thereon. In addition, address electrodes 680 are formed on the front side of the glass substrate 620 serving as the back plate and between the barriers 630 so as to be orthogonal to the composite electrode and parallel to each other.
A fluorescent surface 690 is provided so as to cover the wall surface and the cell bottom surface. The barrier 630 is for defining a discharge space, and each partitioned discharge space is called a cell or a unit light emitting region. This AC type PDP is of a surface discharge type, and has a structure in which an AC voltage is applied between composite electrodes on the front panel to cause discharge. In this case, since the alternating current is applied, the direction of the electric field changes according to the frequency. Then, the phosphor 690 emits light by the ultraviolet light generated by the discharge, and the light transmitted through the front plate can be visually recognized by an observer. Note that DC
The type PDP differs from the AC type in that the electrodes have a structure that is not coated with a dielectric layer, but the discharge effect is the same. FIG. 16 shows an example in which a base layer 667 is provided on one surface of a glass substrate 620, and a dielectric layer 6
Although the structure is provided with 65, the underlayer 667 and the dielectric layer 665 are not necessarily required.

An AC type plasma display panel (PDP) is, for example, as shown in FIG.
Had been produced. FIG. 15 shows an AC-type PDP manufacturing process, in which a back plate and a front plate are manufactured in separate steps, and a PDP is assembled using both. First, the manufacturing process of the back plate will be described. In addition, S51-
S74 represents a processing step. First, a glass substrate is prepared (S51), and a paste for electrode wiring is applied to the entire surface of the glass substrate, dried, processed into a predetermined shape through a plate making process, or a thick film printing method is applied to the glass substrate. After the electrode wiring paste is printed in a predetermined shape, the paste is dried and fired to form an electrode wiring. (S52) Next, a dielectric layer is formed on the entire surface of the formed electrode so as to cover the glass substrate surface. (S53) Next, a barrier (also called a barrier rib) is formed on the dielectric layer of the glass substrate by a printing method or a sandblast method. (S54) In the case of the printing method, a paste for forming a barrier (barrier rib) is printed in a predetermined pattern on a glass substrate by a thick film printing method,
This is dried. The thickness of the barrier is large (for example, 100 to 2).
(Thickness of 00 μm) Since this film thickness cannot be obtained by one thick film printing, printing and drying of the barrier forming paste are performed a plurality of times. After a predetermined film thickness is obtained, the paste is fired. In the case of the sand blast method, a barrier forming material is applied on a glass substrate, and a predetermined resist pattern is further formed thereon. Then, abrasive sand is sprayed to process the barrier forming material into a shape corresponding to the resist pattern. Is fired to form a barrier. Further, a paste for a phosphor (for example, a paste for a phosphor containing indium oxide) is printed in a predetermined pattern on the substrate on which the barrier is formed by a thick-film printing method, and then dried and fired (S55) to obtain a fluorescent material. A body layer is formed to produce a back plate. (S56)

Next, a process for manufacturing the front plate will be described. First, a glass substrate is prepared (S61), and a deposition layer of, for example, ITO (Indium Tin Oxide) is patterned on the glass substrate. (S62) The patterning is performed by a usual photolithography process (lithography technology). Next, three layers of Cr—Cu—Cr (chromium, copper, and chromium) are formed by vapor deposition or sputtering, and a photolithography process (lithography technology) is similarly performed.
To form an electrode wiring for discharge together with the patterned ITO film. (S63) Next, a transparent dielectric layer is formed by solid printing of paste-like low-melting glass (S64), and a protective layer (MgO) is further deposited (S65) to obtain a front plate.
(S66)

Next, a PDP is manufactured using the back plate and the front plate thus obtained as follows. First, the front plate and the back plate are aligned, and in that state, lead glass for sealing is applied to the edges of both substrates, and then sealing is performed. (S71) Next, after the inside of the gap surrounded by both substrates (the back plate and the front plate) and the seal portion is exhausted through the exhaust pipe, the discharge gas is sealed in the above-mentioned gap through the exhaust pipe. . (S72) Thereafter, the exhaust pipe is burned off (chip-off), and a driver IC is mounted (S73) to obtain a PDP. (S74)

As described above, the back plate and the front plate used in the production of the PDP are subjected to various processes to form an electrode wiring portion, a barrier portion, a phosphor portion, a dielectric layer portion, and the like. In addition, it becomes a PDP.

In forming such a phosphor, a phosphor portion (hereinafter also referred to as a phosphor pattern) is formed by forming a photo-curable photosensitive phosphor pattern forming composition after the formation of a barrier. After application to the entire surface on the formation surface side, this is performed by a photolithography process (plate making process) in which exposure, development, and the like are performed using a photomask, and a photolithography method for determining the shape may be employed. In this method, since the top of the barrier on the back plate corresponds to the electrode position on the front plate, it is necessary that the phosphor layer does not remain on the top of the barrier after development. (E.g., baking), and misalignment occurs due to alignment with the photomask. Therefore, the exposure width of the photomask is usually slightly smaller than the barrier interval.
However, in such a conventional method of forming a phosphor pattern using the photolithography method, the phosphor pattern is securely adhered to the entire side surface of the barrier and the entire bottom portion between the barriers, and to the side surface of the barrier and the bottom between the barriers. It was difficult to form it. As shown in FIG.
In some cases, a space 351 may be generated at a corner of the bottom 315A between the barriers on the barrier side, and a gap 352 may be generated along the side surface 313A of the barrier 313. Note that in FIG.
1 is a glass substrate, 312 is an electrode, 313 is a barrier, 313
A is a side surface, 314R is an R (red) phosphor pattern, 31
4G is G (green) phosphor pattern, 314B is B (blue)
The color phosphor pattern 315 is a dielectric layer, and 315A is a bottom. In the case of this method, in addition to the problem that the number of steps is increased and the cost is increased, it has been difficult to form the phosphor pattern on the side surface of the barrier and the bottom between the barriers with good adhesion.

Separately, a method using screen blasting followed by sandblasting described in JP-A-6-5205, and a method using screen printing after applying a crosslinking agent described in JP-A-5-144375 are described in JP-A-6-5205. Although they have been proposed, all use screen printing, and there is an accuracy problem.

In order to cope with these problems in the formation of a phosphor pattern, an ink containing a phosphor (also referred to as a phosphor composition) is discharged from a jet port of an ink jet head described in JP-A-6-162019. There has been proposed a method of drawing a phosphor pattern on a glass substrate (back plate) by jetting. However, the diameter of the ink droplet ejected from the nozzle generally corresponds to approximately the diameter of the nozzle. Although it is necessary to reduce the size of the ink itself, the ink containing the phosphor (phosphor composition) itself has a high viscosity. Since the method includes particles having a large diameter, this method frequently causes clogging of the nozzle, and it has been required to deal with the problem. In addition, while the pitch of the barriers themselves is being narrowed in order to improve the display quality of the plasma display panel, the filling (drawing) of the ink containing the phosphor (also referred to as a phosphor composition) between the narrow barriers by this method is performed. , Has become difficult in terms of accuracy.

[0011]

As described above, in the conventional method of forming a phosphor pattern on the back plate of a plasma display panel, each method has various problems, and the method cannot cope with the quality. There has been a demand for a method of forming a phosphor pattern that can be performed stably and relatively easily. The present invention corresponds to this, and specifically, has at least one or more circular or polygonal orifice of about 50 μm to 1 mm, an opening such as a nozzle, and a part or the whole thereof is used as an electrode. Place and 1000 cps-1000
The composition for forming a phosphor composed of a high-viscosity material of 000 cps is filled, and the composition for forming a phosphor is discharged from the opening by using a discharge unit that discharges the composition for forming a phosphor from an opening. A method of forming a phosphor layer in which a gap between barriers of a back plate for a plasma display panel is filled, and drying and heat treatment are performed as necessary to form a phosphor layer between the barriers and on the side surfaces of the barrier. The nozzle can be formed on the back plate with the phosphor-forming composition, and the viscosity of the phosphor-forming composition is very large or the particle diameter of the phosphor-forming composition is large. An object of the present invention is to provide a method for forming a phosphor layer on a back plate for a plasma display panel, which can be used without causing clogging.

[0012]

According to the present invention, there is provided a method for forming a phosphor layer on a back plate for a plasma display panel, comprising a step of forming at least one opening of a circular or polygonal orifice, nozzle or the like of about 50 μm to 1 mm. And a part or the whole thereof is arranged as an electrode, and 1000 cps to 10 cps.
The composition for forming a phosphor composed of a high-viscosity material of 00000 cps is filled, and the composition for forming a phosphor is discharged from the opening by using a discharge unit that discharges the composition for forming a phosphor from an opening. After filling the gap between the barriers of the back plate for the plasma display panel with the phosphor-forming composition, drying and heat treatment are performed as necessary to form a phosphor layer between the barriers and on the side faces of the phosphor. Then, if necessary, a pressure is applied to the phosphor-forming composition in the discharge means to form a meniscus in the phosphor-forming composition in the opening, and further, the opening of the discharge means through the electrode as necessary. A pulse voltage of a first predetermined voltage value is applied between the portion and the back plate to form an elongated portion in which the meniscus of the phosphor-forming composition is elongated vertically in the opening portion. For phosphor formation between face plate barriers As drips the Narubutsu, and,
Filling the phosphor-forming composition between the barriers of the back plate while relatively moving the back plate and the discharge means for the plasma display panel in the direction along the barrier of the back plate,
Prior to the filling of the phosphor-forming composition between the barriers of the back plate, an extension portion tip positioning step of controlling the extension portion tip position to a predetermined position between the barriers in a state where the extension portions are formed is provided. It is assumed that. Then, in the extension portion tip positioning step in the above, with the extension portion formed, between the opening of the discharge means and the back plate, provided near the extension portion tip, the electric lines of force when applying a pulse voltage. The tip of the elongated portion is brought close to or in contact with a minute needle for controlling, and a pulse voltage of a second predetermined voltage value or more is applied between the opening of the discharge means and the back plate via the electrode. By separating a part of the elongated portion from the tip or by letting it run down from the tip of the elongated portion, the phosphor-forming composition is attached to the needle-like material, and further, the fluorescent material is removed from the fine needle-like material. The composition for forming a body is dropped to a predetermined position between barriers on a back plate, and the composition for forming a phosphor is filled between the barriers. Further, in the above, the surface of the needle-like object is characterized by being processed with fluorine or made of Teflon or a perfluoro fluorine compound. Further, in the above, the distance from the opening to the medium is 0.1 to 10 mm. Further, in the above, the phosphor-forming composition contains particles having a particle diameter of 1/10 or less of the opening diameter of the opening. Further, in the above, the phosphor-forming composition contains particles having an average particle diameter of 1 to 10 μm. In the above, the frequency of the pulse voltage is 10 to 100 kHz.
It is characterized by being.

[0013]

According to the method for forming a phosphor layer of a back plate for a plasma display panel of the present invention, a fine pattern can be formed on the back plate with the composition for forming a phosphor by adopting such a constitution. And for a plasma display panel, which can be used without causing clogging of a nozzle even when the viscosity of the phosphor-forming composition is very large or the particle diameter of the phosphor-forming composition is large. It is possible to provide a method for forming a phosphor layer on the back plate of the present invention. That is, if necessary, a pressure is applied to the phosphor-forming composition in the discharge means to form a meniscus in the phosphor-forming composition in the opening, and further, the opening of the discharge means through the electrode as necessary. A pulse voltage of a first predetermined voltage value is applied between the back plate and the back plate, and in a state where a meniscus of the phosphor-forming composition is elongated vertically in the opening, a back plate is applied from the tip of the extended portion. The phosphor-forming composition is poured between the barriers of the back plate, and the phosphor-forming composition is filled between the barriers of the back plate. Even with a phosphor composition composed of a high-viscosity substance containing large particles, without causing clogging of the opening,
It is assumed that a phosphor composition having a small diameter can be formed.
In particular, prior to filling the phosphor-forming composition between the barriers on the back plate, performing an extension portion tip positioning step of controlling the extension portion tip position to a predetermined position between the barriers with the extension portion formed. This enables stable filling.

Specifically, the step of positioning the distal end of the extension portion includes:
In the state where the extension portion is formed, between the opening of the discharge means and the back plate, provided near the tip of the extension portion, to a fine needle-like object for controlling the electric line of force when applying a pulse voltage, The tip of the extension is brought close to or in contact with it, and a part of the extension is separated from the tip of the extension by applying a pulse voltage of a second predetermined voltage or more between the opening of the discharge means and the back plate via the electrode. Then, the phosphor-forming composition is attached to the needle-like material in such a manner that the composition hangs down from the tip of the elongated portion, and the phosphor-forming composition is further separated from the fine needle-like material between the barriers of the back plate. Is dropped to a predetermined position to fill the gap between the barriers with the phosphor-forming composition, thereby enabling stable filling. In the step of positioning the tip of the extension portion, when the phosphor-forming composition is filled between the barriers at the location, the tip of the extension portion is filled with the filled phosphor-forming composition at a predetermined position between the barriers. It comes into contact with the surface.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view for explaining a step of positioning a leading end of an extension portion, which is a feature of a first example of an embodiment of a method of forming a phosphor layer on a back plate for a plasma display panel according to the present invention. FIG. 3 is a schematic view for explaining an extension portion tip positioning step which is a feature of the second example of the embodiment.
Is a schematic cross-sectional view for explaining the steps of the method for forming a phosphor layer of the back plate for the plasma display panel of the present invention,
FIG. 4 is a schematic configuration diagram of a dispenser for filling the space between the barriers with the phosphor composition, FIG. 5 is a diagram showing another form of the needle-like material, and FIG. 6 is a diagram of the dispenser shown in FIG. FIG. 7 is a diagram for explaining the principle of ejection, FIG. 7 is a diagram for explaining application and separation of a pulse voltage, FIG. 8 is a schematic perspective view of another example of ejection means, and FIG. FIG. 10 is a diagram for explaining control, and FIG. 10 is a diagram for explaining application and separation of a pulse voltage. FIG. 1A is an enlarged view of the vicinity of the extension 18 of the apparatus shown in FIG. 4, and FIG.
FIG. 1A is a view from the A1-A2 side, and FIG. 1C shows a state after a step of positioning the distal end of the extension portion. FIG.
FIG. 2A is a view at a position corresponding to FIG.
FIG. 2B is a diagram of FIG. 2A viewed from the B1-B2 side.
1 to 13, 10 is a phosphor composition, 10 r is a red phosphor composition, 10 g is a green phosphor composition, 10 b is a blue phosphor composition, 10 A is a phosphor layer, and 10 R is red. Phosphor layer for green, 10G for green phosphor layer, 10B for blue phosphor layer, 11 for control unit, 12 for container, 13 for opening,
14 is an electrode, 15 is a power supply, 17 is a meniscus, 18, 1
8A is an extension part, 19 is a drop, 20 is a needle-like object, 25 is a rotating shaft, 30 is a discharging means, 35 is a pressing means, 40 is a container,
1 is an opening, 50 is a fixed part, 60 is a stage, 80 is a back plate, 81 is a glass substrate, 81A is a bottom, 85 is a barrier, 8
5A is the top and 85B is the side.

A first embodiment of a method for forming a phosphor layer of a back plate for a plasma display panel according to the present invention will be described with reference to the drawings. This example is implemented using the dispenser shown in FIG. 4, has an opening 13 formed of one circular orifice in the lower part, a part of the orifice is arranged as an electrode 14, and a phosphor composition 10, and using the discharging means 30 for discharging the phosphor composition from the opening 13, the opening 1 for each phosphor layer of each color to be formed.
3, the phosphor composition 10 is ejected, and the ejected phosphor composition 10 is interposed between the barriers 85 at predetermined positions on the back plate 80 so that the bottom 81A between the barriers and the entire side surface 85B of the barriers are buried, and Fill the top 85A of the barrier without touching it,
The filled phosphor composition 10 is dried and heat-treated to form phosphor layers 10A between the barriers 85 of the back plate 80 and on the side surfaces 85B of the barriers 85. The phosphor composition for the back plate 80 for a plasma display panel This is a method for forming the article 10. The embedding of the phosphor composition 10 between the barriers is performed by applying pressure to the phosphor forming composition in the discharge means as necessary, forming a meniscus in the phosphor forming composition at the opening, and A pulse voltage having a first predetermined voltage value is applied between the opening of the discharge means and the back plate via the electrode according to the above, and the meniscus of the phosphor-forming composition is elongated vertically in the opening. Is formed, the composition for forming a phosphor is caused to flow down from the tip of the extension portion to the barrier of the back plate, and the back plate for plasma display panel and the discharge means are along the barrier of the back plate. While relatively moving in the direction, the phosphor-forming composition is filled between the barriers of the back plate. In the formed state, set the extension tip end position between the barriers Controlling the location, and performs decompression tip positioning step.

The filling of the phosphor composition of each color between the barriers on the back plate is performed, and after the positioning of the distal end of the extending portion, the filling between the predetermined barriers is performed as follows. This will be described with reference to FIGS. First, the extension part tip positioning step is performed as follows. In advance, if necessary, a pressure is applied to the phosphor composition 10 in the discharge means 30 to open the opening 1.
3, a meniscus of the phosphor composition 10 is formed, and an electrode 14 is formed.
A pulse voltage having a first predetermined voltage value is applied between the opening 13 of the discharge means and the back plate 80 through the opening portion 18 to extend the meniscus of the phosphor composition 10 into the opening 13 in a vertically elongated manner. Is formed. The pulse voltage of the first predetermined voltage value for maintaining the extension unit 18 is continuously applied. Next, a fine needle-like object 20 for controlling a line of electric force at the time of applying a pulse voltage between the opening and the back plate 80,
As shown in FIG. 1A and FIG. 1B, the tip of the extension portion 18 is set at a height of the barrier 85 substantially along the center between the barriers 185, and the needle-like object 20 And may come into contact with each other in some cases. In this state, the electrode 14
By applying a pulse voltage of the second predetermined voltage value between the opening 13 of the discharge means and the back plate 80 through the, the part of the extension part 18 is separated from the tip. The separated phosphor composition 10 (drops 19) adheres to the fine needle-like material 20, but falls from the tip to the space between the barriers 85 and is deposited between the barriers 85. Then, as the phosphor-forming composition gradually fills the gap between the barriers at this point, the tip of the elongated portion contacts the filled phosphor-forming composition at a predetermined position between the barriers. Becomes In this state, the needle 20
Is removed and the pressure applied to the phosphor composition 10 in the discharge means 30 is appropriately controlled, as shown in FIG.
The tip of the extension portion contacts the upper surface of the phosphor composition 10 filled between the barriers at substantially the center between the barriers, and the phosphor composition 10 drips from the tip of the extension portion 18 to the side between the barriers. In the state, it is flowed. In addition, in FIG.
0 is omitted. In this way, the extension portion tip position is determined.

Next, the phosphor composition 1 in the discharge means 30
The phosphor composition 10 is moved from the extension 18 to the barrier 8 while the pressure applied to the pressure 0 is appropriately controlled by the pressure means 35 shown in FIG.
Filling the phosphor composition between the barriers of the back plate while the back plate for the plasma display panel and the discharge means are relatively moved in the direction along the barrier of the back plate in a state of being dripped between the back plates; I do. In the present embodiment, the fluorescent composition 10 is filled while the stage 60 is moved and the medium 16 on the stage 60 is relatively moved with respect to the ejection unit 30. The phosphor composition 10 is filled between the barriers so that the phosphor composition 10 does not touch the top 85A of the barrier and covers the entire side surface 85B of the barrier. Extension part 18
Is controlled to a position where the distribution of the electric field is stable at the beginning, so that the filling can be continuously and stably performed.

The filling of the phosphor composition between the barriers 85 on the back plate is performed in this manner, but the above operation is repeated as necessary.

The phosphor composition 10 (phosphor composition for red 10r, phosphor composition for green 10g, phosphor for blue, corresponding to the phosphor layer of each color to be formed over the entire back plate of the plasma display panel) Composition 10b)
Each space is filled between predetermined barriers 85. (Figure 2
(A))

Next, the phosphor layer 1 is dried and heat-treated.
0A (red phosphor layer 10R, green phosphor layer 10G,
The blue phosphor layer 10B) is formed on the entire back plate 80 so as to cover between the barriers and the entire side surface 85B of the barrier. (Figure 2
(B) In this way, the phosphor layers of each color can be filled between the predetermined barriers to form the phosphor layers.

In the dispenser shown in FIG. 4, if the relative position between the needle 20 and the opening 13 is variable within a predetermined range, the method according to the present embodiment further includes the relative position between the needle and the opening. By appropriately controlling the position, it is possible to more accurately control the position at which the droplet 19 adheres to the back plate 80.

In this embodiment, 1000 cps to 1,000,000
The phosphor composition 10 made of a high-viscosity substance of cps is filled between the barriers of the back plate 80, and dried and heated to form a phosphor layer between the barriers and on the side surfaces of the barriers. The diameter of the part is preferably about 50 μm to 1 mm. 1
If it is less than 000 cps, it is not preferable because the shape of the dot adhered on the object cannot be maintained.
In the case of exceeding, it is difficult to fill the nozzle of the phosphor composition 10 with the nozzle. Further, the diameter of the particles contained in the phosphor composition 10 to be ejected is 1 μm of the ejection opening diameter (50 μm to 1 mm).
Up to about / 10 is possible. The phosphor composition 10 applicable to the present embodiment may be formed by kneading a phosphor, a glass frit made of low-melting glass, a binder resin, and an organic solvent, and further adding a thickener.

The binder resin is a cellulose derivative or an acrylic copolymer, specifically, methyl cellulose,
Ethyl cellulose, ethoxycellulose, methylhydroxyethylcellulose, methylhydroxypropylcellulose, methylhydroxypropylcellulose phthalate, methylhydroxypropylcellulose acetate succinate, hydroxypropylcellulose, cellulose propionate, acetylethylcellulose, acetylcellulose, butylcellulose, benzylcellulose, etc. No. In particular, in order to apply the composition for forming a phosphor layer and to make the dried, photosensitive phosphor-forming layer 184 water-developable, a cellulose derivative soluble in both water and an organic solvent, for example, hydroxy. Select and use propylcellulose.

Examples of the thickener to be used include protein-based substances such as casein and casein salts, polyvinyl alcohols, aliphatic amides, acrylic copolymers, polyvinyl-based substances such as polyvinylpyrrolidone, and acrylic-based substances such as sodium polyacrylate. Acid type, polyether type such as polyether dialkyl ester, maleic anhydride type such as vinyl methyl ether-partial ester of maleic anhydride copolymer,
And an organic thickener such as acetylene glycol, and an inorganic thickener such as microsilica, kaolin bentonite and talc, all of which are known in the coatings field. These thickeners are preferably used in a proportion of 0.5 to 10% by weight based on 100 parts by weight of the phosphor layer forming composition.

There is no particular limitation on the phosphor, and a conventionally known phosphor can be used. For example, (Y, Gd) BO ₃ : Eu, YO ₃ : Eu and the like as red phosphors, and Zn ₂ SiO ₄ : Mn and BaAl ₁₂ O as green phosphors.
_{19: Mn, (Ba, Sr} , Mg) O · aAl 2 O 3: M
n such as BaMgAl ₁₄ O ₂₃ : Eu,
BaMgAl ₁₀ O ₁₇ : Eu and the like.

Examples of the organic solvent include ethers, ether esters, esters, amides, alcohols, ketones, acetates, ketone esters, glycols, glycol esters, sulfones, sulfoxides, and halogenated carbons. Hydrogens and hydrocarbons are included.

The opening 13 may be any one that can form a meniscus such as a nozzle and an orifice.

The output voltage of the power supply 15 is frequency 10H
z to 1 kHz can be applied. The distance from the tip of the opening 13 to the back plate 10 is preferably 0.1 mm to 10 mm.

As the needle-like material 20, it is preferable to repel the droplet 19 in order to drop the phosphor composition 10 onto the back plate 80 as it is, and the surface thereof is made of fluorine or made of Teflon or a perfluoro fluorine compound. Is preferred.

Here, the separation of the phosphor composition 10 will be described with reference to FIGS. When a predetermined pressure is applied to the opening 13 of the orifice filled with the phosphor composition 10 from the container 12, a meniscus 17 protruding from the tip opening is formed. (FIG. 6A) In this state, as shown in FIG. 7, a pulse voltage having a voltage value V1 at a repetition frequency of 10 Hz to 1 kHz or less is applied to the electrode 1.
4 and the object 16 (see FIG. 1), the meniscus 17 gradually extends downward, and an extended portion 18 is generated. (FIG. 6 (b) ｃFIG. 6 (c)) When the pulse voltage having the voltage value V1 is repeatedly applied, the extension unit 18 does not extend at a certain position. (FIG. 6D) This state is a state in which the surface tension of the phosphor composition and the downward pulling force due to the electric field and the gravity are balanced. At this time, as shown in FIG. 7, when a pulse voltage having a voltage value V2 is applied, the distal end portion is cut and separated by the extension portion 18 or the cut end is separated by directly contacting the target object. Drops (also referred to as dots) 19 of the phosphor composition are formed on the object. (FIG. 6 (e)) Even if the tip of the extending portion 18 directly contacts the medium (object),
If not, the distal end of the extension 18 separates. When the pulse voltage applied in this state is returned to the voltage value V1, the extension portion 18 contracts slightly and becomes short, and is stabilized in this state, and separation at the distal end portion of the extension portion 18 is not performed. Further, when the application of the pulse voltage is stopped, the extended portion 18 contracts due to the surface tension of the phosphor composition (FIG. 6C ■ FIG. 6).
(B)), returning to the state of the meniscus 17 shown in FIG. Note that the voltage value V of the pulse voltage in the above example is
Since V1 and V2 vary depending on the type of the phosphor composition, it is necessary to appropriately change the voltage according to the viscosity of the substance, the surface tension, the opening diameter of the opening 13, and the like. Although the meniscus 17 has the same diameter as the opening diameter to be discharged, the phosphor composition (drops 19) separated from the tip of the extension 18 extending from the tip of the meniscus is much smaller than the opening diameter. As described above, since the phosphor composition (drops 19) that is separated from the large-diameter opening can be obtained, a wide range of applications can be expected, such as applying the phosphor composition in a thin line or applying it to a narrow area. . Also, by increasing the diameter of the opening, 100
Even a phosphor composition of about 10,000 cps can be filled and discharged.

The formation of the phosphor composition (drops 19) to be separated is performed at the rising and falling timings of the pulse voltage having the voltage value V2 as shown in FIG.
Two droplets 19 are formed for one pulse, but if the time during which the pulse voltage is applied is extremely reduced, one phosphor composition (drop 19) is separated for one pulse.
Is formed. Of course, FIG. 7 shows a case where the time during which the pulse voltage is applied is not extremely short. In FIG. 7, circles indicate
This indicates that one separation is performed at that time (timing). Furthermore, when the magnitude of the voltage value of the pulse voltage is reduced, separation is not performed below a predetermined voltage (voltage value Vm). When the time Tw during which the pulse voltage is applied becomes extremely small, even if the predetermined voltage (voltage value V0) or more is used, only one separated phosphor composition (drop 19) per pulse is applied. Although it may not be formed, if the pulse voltage is equal to or higher than the predetermined voltage (voltage value V0) and the application time is equal to or longer than about 10 mmsec,
Separation is performed at the rising and falling timings of the pulse voltage independently of the application time.

Therefore, for example, a pulse voltage of the voltage value V3, which is higher than a predetermined voltage (voltage value V0), and a pulse voltage of a voltage value V4, which is lower than the predetermined voltage (voltage value Vm), are used. In this way, the separation of the phosphor composition can be controlled. In FIG. 9, the circles indicate that one separation is performed at that time (timing), as in FIG. That is, separation is performed at the rising and falling timings of the pulse voltage of the voltage value V3, and by applying the pulse voltage of the voltage value V4, the extension unit 18 is maintained at a predetermined length. The application is controlled so that the separation can be performed smoothly at the rising and falling timings of the pulse voltage of the voltage value V3. The extension unit 18 is created by applying a predetermined voltage (corresponding to the pulse voltage of the voltage value V1 in FIG. 7).
V1 and V4 do not necessarily have to be the same,
In operation, V1 and V4 may be set to the same value close to Vm (smaller than Vm). Of course, FIG. 9 shows a case where the time Tw during which the pulse voltage is applied is not extremely small.

It is known that a separation is also observed when a pulse voltage is applied as shown in FIG. 10 from the state shown in FIG. 6D. In addition, from the state of FIG.
It is known that the separation is also observed when a pulse voltage is applied as shown in FIG. In this case, one separation is observed at the boundary between two positive and negative pulses. It is also known that no separation is observed when the state shown in FIG. 6D is applied as shown in FIG. In FIG. 10 to FIG.
Like FIG. 7 and FIG. 9, one separation is performed at that time (timing). Of course FIGS. 10 to 12
Also, the time Tw during which the pulse voltage is applied is not extremely small.

In the apparatus shown in FIG. 4, even when the needle-shaped object 20 is not provided, as shown in FIG. 11A, the droplets 19 are stably arranged in the direction of travel of the back plate (thick dotted arrow). If it is, it is not necessary to provide the needle-shaped cover 20, but in practice, the tip position of the extending portion 18 becomes unstable due to various causes, and as a result, as shown in FIG. Then, the droplets 19 are attached to positions that vary from the traveling direction of the back plate 80 (thick dotted arrow). In this example,
As in the apparatus (dispenser) of FIG. 4, the line of electric force when a pulse voltage is applied is adjusted by a needle-like object 20, and a droplet 19 is placed on a predetermined area of the needle-like object 20 as shown in FIG. The needle-shaped object 20 at a predetermined position (FIG. 1A) of the needle-shaped object 20
Of the droplets 19 from the front end of the rear plate 80 to the space between the barriers 85, and when the droplets 19 adhere to the rear plate 80, there is almost no variation in the position of the back plate 80 from the traveling direction. Therefore, the positioning of the distal end of the extension portion is performed accurately.

(Modification) In this embodiment, a total of three devices (dispensers) each having an opening 13 made of one orifice are used for each color. However, the present invention is not necessarily limited to the device having such discharge means 30. . For example, as shown in FIG. 8, using a discharge device in which a number of openings 41 are formed on one surface of a container 40, the container 40 is filled with a phosphor composition and pressurized, and a pulse voltage is applied to the container to open the container. The phosphor composition may be discharged from 41. In this example,
The separated phosphor composition 10 is filled between the barriers 85 of the back plate 80 while moving the stage 60 to change the relative position of the back plate 80 and the opening 13. Is filled with the separated phosphor composition 10 while changing only the relative position of the back plate 80 and the opening 13 by moving only the position of the opening 13 or moving the position of the opening 13 and the movement of the stage. Any way is fine. Also, as shown in FIG. 5, it is possible to rotate around the axis 25, receive the separated phosphor composition (drops 19) at the position 20A, and rotate the separated fluorescent material (state 20B) in the rotated state (state 20B). A method in which the body composition (drops 19) is filled between the barriers 85 of the back plate 80 may be adopted. Moreover, you may heat suitably about 50 degreeC-about 150 degreeC according to the kind of the phosphor composition 10.

Next, a second example of the embodiment will be described. This example is the same as the first example except that the step of positioning the distal end of the extension part is slightly different from the first example. Based on FIG. 2, only the extension portion tip positioning step of this example will be described. In the extension portion tip positioning step of the present example, as shown in FIG. 2, the phosphor composition 10 drips from the tip of the extension portion 18 to the needle 20, and further, from the needle 20,
The phosphor composition 10 is dropped between the barriers 85 on the back plate, and the phosphor-forming composition is filled between the barriers.
Also in the case of the present example, similarly to the first example, if necessary, a pressure is applied to the phosphor composition 10 in the discharge means 30 to form a meniscus of the phosphor composition 10 in the opening 13 in advance. 1
4, a pulse voltage of a first predetermined voltage value is applied between the opening 13 of the ejection means and the back plate 80, and the opening 13
First, the extended portion 18 is formed in which the meniscus of the phosphor composition 10 is elongated vertically. The pulse voltage of the first predetermined voltage value for maintaining the extension unit 18 is continuously applied. Next, a minute needle-shaped object 2 for controlling the lines of electric force when a pulse voltage is applied between the opening 13 and the back plate 80.
0 is substantially at the height of the barrier 85 and substantially along the center between the barriers 185, as shown in FIGS. 2 (a) and 2 (b).
When the tip is set, the tip of the extension part 18 approaches the needle 20, and when the pressure applied to the phosphor composition 10 in the ejection means 30 is appropriately controlled, as shown in FIG. In the meantime, the phosphor composition 10 drips from the tip of the extending portion to the needle-shaped material 20,
Further, it flows down from the needle-like object 20 to between the barriers 85 and is deposited. Then, as in the first example, as the phosphor-forming composition gradually fills between the barriers at this location, the tip of the elongated portion is filled with the filled phosphor-forming composition at a predetermined position between the barriers. It comes into contact with the object surface. In this state, if the needle-like material 20 is removed and the pressure applied to the phosphor composition 10 in the ejection means 30 is appropriately controlled, as in the first example, as shown in FIG.
As shown in (c), the tip of the extension portion contacts the upper surface of the phosphor composition 10 filled between the barriers at substantially the center between the barriers, and from the tip of the extension portion 18 toward the inter-barrier side. Then, the phosphor composition 10 flows in a hanging state. In this way, the distal end of the extension portion is positioned.

In the case of this example, the needle-like material 2
Since 0 is used, positioning of the distal end of the extension portion is accurately performed. Also in the second example, as a modified example, an example using a discharge device (means) as shown in FIG. Also in the second example, the heating may be appropriately performed at about 50 ° C. to 150 ° C. depending on the type of the phosphor composition 10.

[0039]

As described above, according to the present invention, a fine pattern can be formed on the back plate with the phosphor-forming composition, and the viscosity of the phosphor-forming composition is extremely large. It is possible to provide a method for forming a phosphor layer on a back plate for a plasma display panel, which can be used without causing clogging of a nozzle even when the particle diameter of the composition for forming a phosphor is large. did. As a result, it has become possible to respond to refinement, large size, and mass production of plasma display panels.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a step of positioning a leading end of an extended portion, which is a feature of a first example of a method of forming a phosphor layer on a back plate for a plasma display panel according to the present invention.

FIG. 2 is a schematic view for explaining a step of positioning a leading end of an extended portion, which is a feature of a second example of the embodiment of the method for forming a phosphor layer on a back plate for a plasma display panel of the present invention.

FIG. 3 is a schematic cross-sectional view for explaining steps of a method for forming a phosphor layer of a back plate for a plasma display panel according to the present invention.

FIG. 4 is a schematic configuration diagram of a dispenser.

FIG. 2 is a view showing another form of a needle-shaped object.

FIG. 6 is a view for explaining the principle of discharging the phosphor composition of the dispenser shown in FIG. 1;

FIG. 7 is a diagram for explaining application and separation of a pulse voltage;

FIG. 8 is a schematic perspective view of another example of the discharging means.

FIG. 9 is a diagram for explaining separation control of a phosphor composition.

FIG. 10 is a diagram for explaining application and separation of a pulse voltage;

FIG. 11 is a diagram for explaining application and separation of a pulse voltage;

FIG. 12 is a diagram for explaining application and separation of a pulse voltage;

FIG. 13 is a view for explaining the instability of the position of the phosphor composition to be separated;

FIG. 14 is a cross-sectional view for explaining a problem in a phosphor pattern forming method using a conventional photolithography method.

FIG. 15 is a manufacturing process diagram of a plasma display panel.

FIG. 16 is a diagram illustrating a plasma display panel substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Phosphor composition 10r Phosphor composition for red 10g Phosphor composition for green 10b Phosphor composition for blue 10A Phosphor layer 10R Phosphor layer for red 10G Phosphor layer for green 10B Phosphor layer for blue 11 Control Unit 12 Container 13 Opening 14 Electrode 15 Power supply 17 Meniscus 18 Extension unit 19 Drop 20 Needle 25 Rotation axis 30 Discharge unit 35 Pressurization unit 40 Container 41 Opening 50 Fixed unit 60 Stage 80 Back plate 81 Glass substrate 81A Bottom 85 Barrier 85A Top 85B Side

Claims (7)

[Claims] At least one or more circular or polygonal orifices of about 50 μm to 1 mm, openings such as nozzles are provided at the lower part, and a part or the whole thereof is arranged as an electrode, and
The composition for forming a phosphor made of a high-viscosity material of 1000 cps to 1,000,000 cps is filled, and the composition for forming a phosphor is discharged from the opening by using a discharge unit that discharges the composition for forming a phosphor from the opening. After filling the gap between the barriers of the back panel for the plasma display panel with the phosphor-forming composition, drying and heat treatment are performed as necessary to form a phosphor layer between the barriers and on the side walls of the phosphor. A method of applying a pressure to the phosphor-forming composition in the discharging means as required, forming a meniscus in the phosphor-forming composition in the opening, and further discharging the ink through the electrode as necessary. A pulse voltage of a first predetermined voltage value is applied between the opening and the back plate to form an elongated portion in which the meniscus of the phosphor-forming composition is elongated in the opening. From the back plate The composition for forming a phosphor is formed such that the composition for forming a phosphor drips between the walls, and the back plate for the plasma display panel and the discharge unit are relatively moved in a direction along a barrier of the back plate. The material is filled between the barriers on the back plate, and before the filling of the phosphor-forming composition between the barriers on the back plate, the extension portion tip is positioned at a predetermined position between the barriers with the extension portion formed. A method for forming a phosphor layer on a back plate for a plasma display panel, wherein the method comprises a step of controlling an extension portion tip position control. 2. The method according to claim 1, wherein the step of positioning the distal end of the extension portion includes the step of applying a pulse voltage provided between the opening of the discharge means and the back plate and in the vicinity of the distal end of the extension portion while the extension portion is formed. The tip of the elongated portion is brought close to or in contact with a minute needle-like object for controlling the electric line of force, and a pulse having a voltage equal to or higher than a second predetermined voltage value between the opening of the discharge means and the back plate via the electrode. By applying a voltage, a part of the extended portion is separated from the tip of the elongated portion, or is allowed to flow down from the tip of the elongated portion, so that the phosphor-forming composition is attached to the needle-like material, and A back plate for a plasma display panel, wherein a phosphor-forming composition is dropped from a needle-shaped material to a predetermined position between barriers on a back plate, and the phosphor-forming composition is filled between the barriers. Phosphor layer forming method. 3. The phosphor layer formation of a back plate for a plasma display panel according to claim 1, wherein the surface of the needle-shaped material is processed with fluorine or made of Teflon or a perfluorofluorine compound. Method. 4. The method according to claim 1, wherein the distance from the opening to the medium is 0.1 to 10 mm. 5. The back plate for a plasma display panel according to claim 1, wherein the composition for forming a phosphor contains particles having a particle diameter of 1/10 or less of the opening diameter of the opening. Phosphor layer forming method. 6. The method for forming a phosphor layer on a back plate for a plasma display panel according to claim 1, wherein the composition for forming a phosphor contains particles having an average particle diameter of 1 to 10 μm. . 7. The method according to claim 1, wherein the frequency of the pulse voltage is 10 to 100 kHz.