JPH09202995A - Phosphor electrodeposition solution and method for forming phosphor layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphor electrodeposition solution excellent in electrification stability and redispersibility in the soln., excellent in adhesion even when deposited through a dielectric layer as well as when deposited directly on an exposed electrode, high in packing density and capable of forming a uniform phosphor layer and to furnish a method for forming a phosphor layer. SOLUTION: This phosphor electrodeposition soln. is prepared by dispersing a resin grain occluding an inorg. phophor in an electrical insulating dispersion medium. A body to be electrodeposited provided with an electrode and a counter electrode are arranged in the electrodeposition soln., the resin grain occluding the inorg. phosphor is deposited on the body by electrophoresis, and a phosphor layer is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor electrodeposition liquid for forming a phosphor layer, and a plasma display panel (hereinafter referred to as PDP) which is a self-luminous type flat panel display using gas discharge, a fluorescent display tube. The present invention relates to a phosphor layer forming method for cathode ray tubes, cathode ray tubes and the like.

[0002]

2. Description of the Related Art Generally, a PDP has a structure in which a pair of regularly arranged electrodes is provided on one or the other of two opposing glass substrates, and a gas mainly containing Ne or the like is sealed between the two substrates. During operation, a voltage is applied between both electrodes to generate a discharge in the minute cells around the electrodes, thereby causing the phosphor layer in each cell to emit light for display. In order to display information, cells arranged regularly are selectively discharged and emitted. P
There are two types of DP, a direct current type (DC type) and an alternating current type (AC type), and both are classified into a refresh drive system and a memory drive system depending on the difference in display function and drive method.

FIG. 1 is a perspective view showing one structural example of an AC type PDP. In the figure, 1 is a front plate, 2 is a back plate,
3 is a barrier rib, 4 is a sustain electrode, 5 is a bus electrode, 6 is a dielectric layer, 7 is a MgO layer, 8 is an address electrode, and 9 is a phosphor layer.

FIG. 1 shows a front plate 1 and a rear plate 2 for the sake of explanation.
It is shown in a state where is separated. As shown in FIG.
In the AC type PDP, a front plate 1 and a rear plate 2 made of glass are opposed to each other in parallel, and a barrier rib 3 provided upright on the rear plate 2 forms a cell in which the front plate 1 and the rear plate 2 are sealed. It is fixed at a fixed interval.

On the back side of the front plate l, a composite electrode composed of a sustain electrode 4 which is a transparent electrode and a bus electrode 5 which is a metal electrode is formed in parallel with each other, and covers the dielectric layers 6 and M.
The gO layer 7 is sequentially formed.

Address electrodes 8 are formed in stripes parallel to each other on the rear plate 2 side so as to be orthogonal to the composite electrodes and between the barrier ribs 3, and fluorescent light is formed on the cell bottom surface on the address electrodes 8. A body layer 9 is provided.

As shown in the sectional view of FIG. 2, the address electrode 8 is formed after the underlayer 10 is formed on the glass substrate 2.
There is also a structure in which the barrier rib 3 and the phosphor layer 9 are provided after the dielectric layer 6'is further laminated.

Such an AC type PDP is a surface discharge type and is divided into a front plate 1, a rear plate 2 and a barrier rib 3 by applying a predetermined voltage between the composite electrodes on the front plate to form an electric field. Discharge is performed in each cell as a display element. Then, the phosphor 9 is caused to emit light by the ultraviolet rays generated by this discharge, and the light transmitted through the front plate 11 can be visually recognized by the observer.

3A and 3B show an example of the configuration of a DC type PDP. FIG. 3A is a plan view and FIG. 3B is a drawing A.
6 is a cross-sectional view taken along line XX in FIG. In the figure, 11 is a front plate, 12 is a back plate, 13 is a cathode, 14 is an electrode body, 15 is a display anode, 16 is a barrier rib, 17 is a discharge cell, 18
Is a terminal portion, 19 is a resistor, 20 is an auxiliary electrode, 21 is an electrode body, 22 is a phosphor layer, and 23 is a priming slit.

As shown in FIG. 3, the DC type PDP is formed into a panel by combining two glass substrates, a front plate 11 and a rear plate 12, and on the front plate 11 a first cathode 13 is formed. An electrode group is formed, and on the back plate 12, a second electrode group including four electrically connected electrodes and a display anode 15 is formed. The cathode 13 and the display anode 15 are formed so that the front plate 11 and the rear plate 12 are held opposite to each other by the barrier ribs 16 so as to be substantially orthogonal to each other to form the discharge cell 17. The cathode 13 and the electrode body 14 in the discharge cell 17 form a unit discharge electrode pair. The anode bus 15 includes a linear portion 15a and a protrusion 15b protruding laterally from the linear portion 15a, and a terminal portion 18 extends from the electrode body 14 in parallel with the anode bus 15. Projection 15
A resistor 19 electrically connects between b and the terminal portion 18 of the electrode body 14. In addition, the adjacent display anode 15
Auxiliary anode 20 is provided in parallel with it,
An electrode body 21 is also provided on the auxiliary anode 20 at a position intersecting with the cathode 13.

In the DC type PDP, the cathode 13 and the display anode 1
When a predetermined voltage is applied between the electrodes 5, a current flows through the electrode body 14 through the resistor 19 and the cathode 13 is formed in the discharge cell 17.
A discharge occurs between the electrode body 14 and the electrode body 14, and the ultraviolet rays generated by this discharge cause the phosphor layer 22 of, for example, RGB three colors to emit light. This light emission is radiated to the outside through the front plate l1, and full-color image display is performed. In this case, the assisting anode 18 has a role of supplying charged particles, which become the pilot fire of the discharge, into the discharge cell 17 through the priming slit 23. Reference numeral 14 is a dielectric layer, which electrically isolates the display anode 15, the terminal portion 18, the resistor 19 and the auxiliary anode 20 from the discharge space, and defines the discharge generation place only in the electrode bodies 14 and 21.

Conventionally, such AC type PDP and DC type P
As a method of laminating the phosphor layer 9 and the phosphor layer 22 in the DP, filling is mainly performed by screen printing or the like. In addition, recently, the electrodeposited body and the counter electrode are opposed to each other in the electrodeposition liquid, and voltage is applied to the striped electrode and the counter electrode of the electrodeposited body to perform electrodeposition to form a phosphor layer. Ways to do so are also being considered.

As such an electrodeposition liquid, a phosphor dispersed in an aqueous solution containing an electrolyte such as aluminum nitrate or a non-aqueous solution, or a phosphor dispersed in a partially ionized resin aqueous solution is used. ing. In the case of a color display PDP, the above-mentioned electrodeposition step is repeated for each phosphor whose emission color is red, green and blue to form a phosphor layer.

When an electrodeposition liquid in which a phosphor is dispersed in an aqueous solution containing an electrolyte or a non-aqueous solution is used, the charged phosphor moves toward the electrode by electrophoresis and is deposited on the electrode to cause fluorescence. The body layers are laminated, and when the dispersion aqueous solution consisting of the phosphor and the partially ionized resin is used as the electrodeposition liquid, the ionized resin and the phosphor move toward the electrodes by electrophoresis, The resin is insolubilized by the transfer of electrons on the electrode, whereby the phosphor is deposited and adhered on the electrode together with the resin to be laminated.

However, when the water-soluble electrodeposition liquid is used, gas is generated by electrolysis of water on the electrode to be electrodeposited, and the density of the electrodeposited phosphor is deteriorated. There is a problem that the adhesive strength also deteriorates. In addition, an electrodeposition liquid in which the phosphor is dispersed in an aqueous solution containing an electrolyte or a non-aqueous solution has poor charge stability of the phosphor, and therefore the electrodeposition conditions must be changed appropriately, and the phosphor deposited on the electrode cannot be There is a problem that the adhesion is very weak and the phosphor peels off in the washing step after electrodeposition, making it difficult to form a uniform phosphor layer.

Moreover, when the phosphor layer is electrodeposited on the panel in which the dielectric layer 6'is formed on the address electrodes as in the PDP described in FIG. 2, since the electrodes are not exposed, water electricity is not applied. Although no decomposition occurs and no gas is generated, no H ⁺ or OH ⁻ is generated by electrolysis of water, and insolubilization of ionized resin and insolubilization of resin by cross-linking reaction by Kolbe type decomposition can also occur. In addition, there is a problem that the electrodeposition method is limited because electrodeposition cannot be performed.

[0017]

SUMMARY OF THE INVENTION The first object of the present invention is to solve the above problems and is excellent in charge stability and redispersibility in an electrodeposition solution. In addition, when the electrodeposition is performed directly on the exposed electrode, or even when the electrodeposition is performed through the dielectric layer, the adhesion is excellent, the packing density is high, and a fluorescent layer that enables the formation of a uniform phosphor layer is formed. The purpose is to provide a body electrodeposition solution.

A second object of the present invention is to maintain a stable electrodeposition condition and fill the phosphor layer by forming the phosphor layer by an electrodeposition method using the above-mentioned phosphor electrodeposition liquid. It is an object of the present invention to provide a phosphor layer forming method that can improve the density and form a uniform phosphor layer.

[0019]

The phosphor electrodeposition liquid of the present invention is characterized in that resin particles containing an inorganic phosphor are dispersed in an electrically insulating dispersion medium.

The resin particles containing the inorganic phosphor are copolymer resin particles, and the copolymer resin particles have a core portion which is insoluble or swells in the electrically insulating dispersion medium. It is characterized in that it is dispersed in such a state that it encloses the core portion and has an outer edge portion that swells or dissolves in an electrically insulating dispersion medium.

Further, the method for forming a phosphor layer of the present invention is a method for forming an electrodeposited body in which electrodes are arranged in an electrodeposition liquid in which resin particles containing an inorganic phosphor are dispersed in an electrically insulating edge dispersion medium. And a counter electrode are arranged, and by electrophoresing, resin particles containing an inorganic phosphor are electrodeposited on the electrodeposited body to form a phosphor layer.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The phosphor electrodeposition liquid of the present invention will be described. The fluorescent substance is an inorganic fluorescent substance which emits light when excited by ultraviolet light. For example, the fluorescent substance having a red emission color is Y ₂ O ₃ : Eu, Y ₂ Sio ₅ : Eu, Y ₃ Al _{5
O 12: Eu, Zn 3 (} PO 4) 2: Mn, YBO 3: E
u, (Y, Gd) BO ₃ : Eu, ScBO ₃ : Eu, L
uBO ₃ : Eu and the like are exemplified.

Zn ₂ Si having a green emission color is used.
O ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, SrAl ₁₃ O ₁₉ :
Mn, CaAl ₁₂ O ₁₉ : Mn, YBO ₃ : Tb, BaM
gAl ₁₄ O ₂₃ : Mn, LuBO ₃ : Tb, GdBO ₃ :
Tb, ScBO ₃ : Tb, Sr ₆ Si ₃ O ₃ Cl ₄ : E
u etc. are illustrated.

As the light emitting color of blue, Y ₂ SiO
₅ : Ce, CaWO ₄ : Pb, BaMgAl ₁₄ O ₂₃ : E
u etc. are illustrated.

The inorganic phosphor may be colored with a coloring pigment as long as it is a pigment having heat resistance equal to or higher than the temperature at the time of firing during the substrate manufacturing process.

Examples of such coloring pigments include cadmium sulfur selenide, red iron oxide (Fe ₂ O ₃ ), cuprous oxide, cadmium mercury red (CdS + HgS), chrome vermillion,
Silver vermilion, antimony red iodine red, zinc iron red,
Molybdenum red, red lead, cadmium red, chrome green, zinc green, cobalt green, chromium oxide, viridian, emerald green ultramarine blue, navy blue, cobalt blue,
Cerulean blue, copper sulfide, titanium yellow, titanium black, black iron oxide (Fe ₃ O ₄ ), yellow iron oxide, cadmium yellow, yellow lead, complex oxide pigments (Cr, C
o, Ni, Fe, Mn, Cu, Sb, As, Bi, T
i, Cd, Al, Ca, Si, Mg, Ba, and the like) are pigments composed of oxides of two or more kinds of metals.

Regarding the method of coloring the phosphor, a method of adding and dispersing during the process for producing an electrodeposition liquid described later or JP-A-50-56 is used.
Although there is a method disclosed in Japanese Patent No. 146, etc., preferably, Mechanofusion system (manufactured by Hosokawa Micron Co., Ltd.), hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system “KOSMOS” (manufactured by Kawasaki Heavy Industries, Ltd.), supermarket It is preferable to fuse the pigment to the surface of the phosphor by using a particle compounding device such as a hybrid mill (manufactured by Ishikawa Harima Heavy Industries Ltd.).

The particle size of the phosphor particles is 0.1 μm to 15 μm, preferably 0.5 μm to 8 μm in terms of primary average particle size.
It is good to set m.

Resins containing phosphor particles include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, methyl methacrylate, methyl acrylate, ethyl acrylate, ethyl methacrylate, propyl methacrylate, propyl acrylate, n-butyl methacrylate. , Isobutyl methacrylate, 2-ethylhexyl methacrylate, 2-hexyl acrylate, lauryl methacrylate, lauryl acrylate, stearyl methacrylate, stearyl methacrylate, dodecyl methacrylate, dodecyl methacrylate, hexyl methacrylate, hexyl acrylate, octyl methacrylate, octyl acrylate, cetyl methacrylate, cetyl. Acrylate, nonyl methacrylate,
Nonyl acrylate, decyl methacrylate, decyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, 2-methoxyacrylate, 2 (2-ethoxyethoxy) ethyl acrylate, 2-hydroxyxyethyl methacrylate, diacetone acrylamide , N, N-dimethylaminopropylacrylamide, N, N-diethylacrylamide, isopropylacrylamide, diethylaminoethylmethacrylate, t-butylmethacrylate, N, N-dimethylacrylamide, vinyltoluene, vinylacetate, etc. Copolymer composed of two or more kinds of monomers selected from monomers, polystyrene, poly- - methyl styrene, styrene-propylene copolymer rest, styrene-butadiene copolymer, and polystyrene-based resins such as styrene-isoprene copolymer,
Examples thereof include cellulose derivatives such as ethyl cellulose, methyl cellulose and hydroxypropyl cellulose, polyester resins such as polyacrylic esters and alkyd resins, and polyolefin resins such as ethylene-acrylic acid copolymers and ethylene-vinyl acetate copolymers.

In the present invention, the resin has adsorptivity to the phosphor and is excellent in dispersibility in the electrically insulating dispersion medium,
Furthermore, it is required to give positive or negative charges to the phosphor particles and to have excellent fixability of the electrodeposition liquid particles after electrodeposition. For that purpose, the resin containing the inorganic phosphor is preferably a copolymer resin having a specific relationship to be described later with the electrically insulating dispersion medium, whereby the copolymer resin particles containing the phosphor are electrically conductive. A core part that is insoluble or swells in the electrically insulating dispersion medium in the insulating dispersion medium, and wraps the core part,
In addition, it is possible to disperse in a state consisting of an outer edge portion that swells or dissolves in an electrically insulating dispersion medium. For example, even phosphor particles having a large particle size (1 μm or more) can be prevented from settling and aggregating, and have good redispersibility. It can be a phosphor electrodeposition liquid.

The relationship between the copolymer resin and the dispersion medium will be described. The copolymer resin is formed by copolymerizing at least two kinds of monomers, and a solubility parameter value (hereinafter referred to as SP value) δp of a homopolymer composed of only at least one monomer component in the copolymer resin. ¹ and the SP value δs ¹ of the dispersion medium (δp ¹ −δ
s ¹ = Δδ ¹ ) is 1.0 or more, and the difference (δp) between the SP value δp ^{2 of the} homopolymer composed only of at least one other monomer component and the SP value δs ¹ of the dispersion medium.
² −δs ¹ = Δδ ² ) is 1.0 or less, and Δδ ¹
Difference between .DELTA..delta ² and Δ (Δδ ¹ -Δδ ²⁾ at least 0.
When the copolymer resin has a relationship of 5 or more, when the copolymer resin is dispersed in the dispersion medium, the resin particles surround the insoluble core portion and the core portion in the electrically insulating dispersion medium, and Consisting of an outer edge portion that dissolves or swells in a hydrophilic dispersion medium,
The dispersion stability will be excellent.

Generally, the SP value is known to indicate compatibility or incompatibility between substances. Taking the relationship between a resin and its solvent as an example, the SP value indicates the solubility of the resin in the solvent. The degree can be indicated, and if the difference in SP value between the two is small, the solubility of the resin in the solvent is large, and if the difference is large, the solubility is small and the resin becomes insoluble. As a method of measuring the SP value of the resin, for example, (1) a dissolution method, that is, a method of estimating from the SP value of a solvent that dissolves the resin (H. Burrell, Official
Digest, 27 (369), 726 (1950)), (2) Swelling method, that is, for resins that are difficult to dissolve, a method of estimating from the SP value of the solvent that maximizes the degree of swelling (Id.), (3) ) A method of obtaining from the intrinsic viscosity of the resin, that is, the intrinsic viscosity of the resin in the solvent shows the maximum value when the SP value of the resin and the SP value of the solvent match. Therefore, a method of dissolving the resin in a solvent having various SP values, measuring the intrinsic viscosity of each, and estimating the SP value of the resin from the solubility parameter value of the solvent that gives the maximum value as the intrinsic viscosity (H. Ahmed, M , Yasse
n, J.Coat.Technol., 50,86 (1970), WRSong, DWBrown
awell, Polym.Eng.Sci., 10,222 (1970)), (4) Method of obtaining from molecular attraction constant, that is, molecular attraction constant (G) of each functional group or atomic group constituting the resin molecule, and molar volume ( V) from the equation SP value = ΣG / V (DASmall, J.Appl.Chem., 3,71, (1953), KLHoy, J.
Paint Technol., 42,76 (1970)) is known. Less than,
The SP value of the resin is the value obtained from the molecular attraction constant, and the SP value of the solvent is Hildebrand-S
Solution theory of catchard (JHHildebrand, RLScott, "T
he Solubility of Nonelectrolytes '' 3rd Ed., Reinhold
Publishing cop., New York (1949), G. Scatchard, Che
Based on m.Rev., 8,321 (1931), obtained by considering the attractive force between molecules, SP value (δ) = (ΔE _v / ΔV ₁ ) ^1/2 (where
ΔE _v : evaporation energy, V ₁ : molecular volume, ΔE _v /
V ₁ : cohesive energy), and in the present invention, KLHoy, “J.
25 ° C, described in Paint Technol., 42,76 (1970)
Use the value in.

Taking the case where the resin is dissolved in a solvent as an example, the relationship between the SP values of the resin and the solvent will be described. Polystyrene having an SP value of 9.1 has an SP value of 9.1.
Is very soluble in tetrahydrofuran and has an SP value of 8.5 to 9.3 and is soluble in solvents.
It is completely insoluble in n-hexane with a value of 7.3. In this way, the state of the resin in the solvent can be estimated by observing the difference between the SP values of the resin and the solvent.

Further, the resin particles can be precipitated by dissolving the resin in the good solvent in a relatively dilute state, adding the solution to the poor solvent, and removing the good solvent. However, it is thought that this is a resin that was present in a single solvent in a good solvent and in a state where the molecular chain was extended, but in the poor solvent, the molecular chain shrinks, becomes a particle, and precipitates. it can. Therefore, the poor solvent should be a solvent having a difference in SP value such that the resin swells, or S
The difference in P value is large, and the state of particles in the solvent differs depending on whether the resin is a completely insoluble solvent. Moreover, in general, the larger the weight average molecular weight of the resin, the larger the particle size of the resin particles formed.

Although there is such a general relationship between a resin and its solvent, a copolymer resin is used as the resin,
The present inventors have conducted experiments to find that when the particles are allowed to exist in a solvent having a specific SP value, the particle size of the precipitated resin particles changes proportionally as the ratio of the monomer composition in the copolymer resin changes. I have confirmed it.

In examining the law, at least 2
By considering a copolymer resin composed of one or more kinds of monomer components as a homopolymer composed only of the at least one kind of monomer component and a homopolymer composed only of other at least one kind of the monomer component, From the solubility of each homopolymer in the solvent, the dissolved state of the copolymer resin in the solvent can be defined.

On the basis of the above consideration, the relationship regarding the SP value between the above-mentioned copolymer resin and the dispersion medium is as follows: (1) at least one monomer component in the copolymer resin difference .DELTA..delta ¹ between SP value .delta.s ¹ of SP value .delta.p ¹ and a dispersion medium of a homopolymer composed only of 1.0 or more, preferably 1.5 or more,
(2) SP value δp ^{2 of} homopolymer composed only of at least one other monomer component and SP value δ of dispersion medium
The difference Δδ ² with s ¹ is 1.0 or less, preferably 0.5 ≦ Δ
δ ¹ ≦ 1.0, and (3) these Δδ
¹ and the difference between ^{Δδ 2 Δ (Δδ 1 -Δδ 2} ) of at least 0.5 or more, preferably by defining 1.0 or more, and an insoluble part in the solvent defined in (1), the insoluble portion Which is a copolymer resin particle having an outer edge portion including a dissolved or swollen portion defined in (2) above.

Such a shape of the obtained copolymer resin particles is such that the portion insoluble in the dispersion medium is incompatible with the dispersion medium,
Further, as a result of the portion that dissolves or swells in the dispersion medium having an affinity with the dispersion medium, the insoluble portion becomes the core portion and is dissolved,
Or, it is considered that the particle has a double-layered particle structure in which the swelling portion is the outer edge portion, and the particle diameter increases when the proportion of the swelling portion increases, and the particle diameter decreases when the proportion of the swelling portion decreases. It is supposed to be.
Further, as a component in the copolymer resin, the dissolved portion does not contribute to the particle size when it is considered to dissolve,
It is considered that the particle size depends on the insoluble portion (see, for example, Japanese Patent Application No. 6-63062).

The copolymer resin in the present invention satisfies such a relationship. Among the copolymer resins shown above, one of the combinations (monomer A) is 2-ethylhexyl methacrylate, 2-ethylhexyl methacrylate. Examples thereof include ethylhexyl acrylate, lauryl methacrylate, lauryl acrylate, stearyl methacrylate, stearyl acrylate, hexyl methacrylate, hexyl acrylate, dodecyl methacrylate and dodecyl acrylate.

As the other (monomer B) of the combination, acrylic acid, methacrylic acid, itaconic acid, 2-
Metacroyloxysuccinic acid, 2-metacroyloxyfumaric acid, 2-hydroxyethyl methacrylate, 2-
Examples thereof include hydroxypropyl methacrylate, 2-hydroxypropyl acrylate and 2-hydroxybutyl methacrylate.

Preferred combinations include 2-ethylhexyl methacrylate-methacrylic acid copolymer, stearyl methacrylate / acrylic acid copolymer, stearyl methacrylate / 2-hydroxymethacrylate copolymer, 2-ethylhexylmethacrylate / 2-hydroxyethyl methacrylate copolymer. Examples thereof include polymers.

The copolymer resin has a melt flow rate (MFR) defined by ASTM D-1238 of 1 dg / m.
in to 400 dg / min, preferably 2 dg / min
It is preferably about 150 dg / min. The range of this MFR value is about 60,000 to 25 in terms of weight average molecular weight.
This corresponds to 10,000, preferably 75,000 to 200,000.

As the electrically insulating dispersion medium, 10 ¹⁰ Ω · c
A material having a volume resistance of m or more, a known material can be used, and a mixture of two or more kinds of dispersion medium may be used. In that case, the volume resistance of the mixed dispersion medium is 10 ¹⁰ Ω. It may be cm or more.

Examples of the electrically insulating dispersion medium include hexane, heptane, octane, nonane, decane, decane, dodecane, cyclohexane, toluene, xylene and Isopar C, Isopar E, Isopar G, Isopar H manufactured by Exxon Chemical Co. , Isopar L, Isopar M, Naphtha No. 3, naphtha No. 5, naphtha No. 6, naphtha No. 7, Solvesso 100, Solvesso 150, Solvesso 200, Exol D30, Exol D40,
Exol D80, Exol D100, etc., and IP Solvent 1016, IP Solvent 1620, IP Solvent 2028, IP Solvent 2 manufactured by Idemitsu Petrochemical Co., Ltd.
835 or the like. The SP values of these trade names are approximate to n-hexane (7.3).

Here, SP in the copolymer resin and the dispersion medium
The relationship between the values will be illustrated. For example, when 2-ethylhexyl methacrylate-methacrylic acid copolymer resin is used, poly (2-ethylhexyl methacrylate) is used.
Has an SP value of 7.7 and polymethacrylic acid has an SP value of 9.4.
When n-hexane (SP value 7.3) is used as the dispersion medium, Δδ ¹ is 9.4-7.3 = 2.1, Δδ ²
Is 7.7−7.3 = 0.4, and Δ (Δδ ¹ −Δ
δ ² ) is 1.7, which satisfies the above relationship. The copolymer resin particles are
It can be considered that the portion derived from the ethylhexyl methacrylate component forms the outer edge portion as a dissolved or swollen portion, and the portion derived from the methacrylic acid component forms an insoluble core portion.

The particle size of the copolymer resin particles containing the phosphor is usually adjusted appropriately within the range of 0.1 μm to 15 μm. The content of the copolymer resin particles containing the phosphor in the electrodeposition liquid is 0.01% by weight to 80% by weight,
The ratio is preferably 0.1% by weight to 50% by weight. The copolymer resin particles in the present invention have excellent dispersion stability due to their surface affinity with the dispersion medium without causing gelation, aggregation, precipitation, etc. even if the particle concentration is increased. The copolymer resin is 1% by weight to 50% with respect to the phosphor.
It can be 0% by weight, preferably 5% by weight to 200% by weight.

Next, a dispersant, a charge control agent or the like may be added to the electrodeposition liquid of the present invention so as to impart a function of stably dispersing particles in the electrodeposition liquid and a charging property. is there.

Examples of such dispersants include metal soaps such as zirconium naphthenate and aluminum stearate, natural phosphates such as lecithin, aliphatic amines, anionic surfactants, cationic surfactants and amphoteric interfaces. Activators, nonionic surfactants and the like are used. The dispersant may be added in an amount of not more than 200% by weight, preferably not more than 50% by weight, based on the copolymer resin, in the granulation step in the production step of the electrodeposition solution described below. Hereafter, it may be contained in a proportion of preferably 10% by weight or less.

As the charge control agent, cobalt dialkylsulfosuccinate, manganese dialkylsulfosuccinate,
Zirconium dialkyl sulfosuccinate, yttrium dialkyl sulfosuccinate, dialkyl sulfosuccinic acid metal salts such as nickel dialkyl sulfosuccinate, manganese naphthenate, calcium naphthenate, zirconium naphthenate, cobalt naphthenate, iron naphthenate, lead naphthenate, nickel naphthenate, Chromium naphthenate, zinc naphthenate, magnesium naphthenate, manganese octylate, calcium octylate, zirconium octylate, iron octylate, lead octylate, cobalt octylate, chromium octylate, zinc octylate, magnesium octylate, dodecylate Manganese, calcium dodecylate, zirconium dodecylate, iron dodecylate, lead dodecylate, cobalt dodecylate, chromium dodecylate, zinc dodecylate, dodecylate Preferred are metal soaps such as gnesium, calcium dodecylbenzene sulfonate, sodium dodecylbenzene sulfonate, metal salts of alkylbenzene sulfonates such as barium dodecylbenzene sulfonate, phospholipids such as lecithin and sehalin, and organic amines such as n-decylamine. May be added. The addition amount of the charge control agent may be the minimum amount showing the charge control effect, but it is usually preferably 0.01 to 50% by weight in the electrodeposition liquid. The charge control agent exhibits a charge control effect when added at any stage during the production process described below or in the electrodeposition liquid after removing the solvent, but preferably during the production process before the granulation process. It is good to add to.

Next, the method for producing the electrodeposition liquid of the present invention will be described. The method for producing the electrodeposition liquid in the present invention includes (1)
Phosphor, or a phosphor fused with a pigment, or a step of dissolving the copolymer resin in a good solvent in the presence of the phosphor and the pigment,
(2) A solution in which a copolymer resin is dissolved, and a step of mixing with an electrically insulating dispersion medium to granulate the copolymer resin particles (3) a step of removing the solvent.

First, the solvent used in the step (1) is one capable of dissolving the copolymer resin at room temperature (25 ° C.). In this case, depending on the constituent components of the copolymer resin, Even if it is not in a swollen state and is in an insoluble state, it is sufficient if the dispersed state of the monomolecular chain is good.

Examples of such a solvent include solvents having a boiling point lower than that of the electrically insulating dispersion medium, for example, cyclohexane, ethyl acetate, cellosolve acetate, toluene, tetrahydrofuran, methyl ethyl ketone, cyclohexanone,
Acetone, dioxane, ethyl cellosolve, cyclohexanol, methyl cellosolve, isopropyl alcohol, ethanol, methanol and the like can be mentioned, and they may be appropriately selected and used depending on the solubility with respect to the resin.

The dispersant described above was added to the resin solution in an amount of 0.
It is advisable to contain it in the range of 3% by weight to 0.5% by weight. Further, the amount of the copolymer resin dissolved in the solvent can be arbitrary, but if the resin ratio is too high, the resin particles may come into contact with each other in the precipitation step of the resin particles, and a gelled mass may be formed. 1-80% by weight, preferably 5
It is advisable to use a dilute solution of 10% by weight.

Next, in the granulation step of (2), (1)
The solution prepared in (1) is mixed with the electrically insulating dispersion medium described above. When the resin is granulated in the presence of the phosphor particles, the phosphor particles can be included in the copolymer resin particles.
At that time, the resin molecular chains dispersed in the solution are entangled to form phosphor particles by being added to the electrically insulating dispersion medium that is a poor solvent, and the particles are formed to form the phosphor. The surface of the resin particles encapsulating the particles becomes a dissolved or swollen portion in the copolymer resin, and even if the phosphor particles are contained, the phosphor particles do not come into contact with each other and the dispersion stability can be excellent.

The solvent used in the granulation step is preferably removed by decantation, an evaporator or the like from the viewpoint of granulation property. Further, as a dispersion method for adjusting the particle size of the resin particles, it is preferable to perform mixing, stirring and dispersion with a mixing stirrer such as a paint shaker, an ultrasonic homogenizer or a medialess disperser. Dispersion by a disperser using media such as a ball mill, a sand mill, or a bead mill is not desirable because it also crushes the primary particles of the phosphor and deteriorates the luminous efficiency of the phosphor.

Next, the phosphor layer forming method of the present invention will be described by taking the phosphor layer on the back plate of the PDP as an example.

A method for producing an electrodeposited body will be briefly described with reference to FIG. 1 as an example. First, a glass substrate 2 to be a back plate.
The address electrode 8 is pattern-formed on or above the underlying layer.

As a method of forming the electrodes, (1) a method of combining a thin film forming process such as a sputtering method and a vacuum deposition method with a photo process, (2) a method using a screen printing method, and (3) a blade There is a method in which a coating method such as coating and reverse coating is combined with a photo process. As the photo process, there is a method in which a photoresist is applied and dried, and then patterned by an exposure and development process, or a method in which a dry film resist is similarly used for patterning.
The film thickness of the electrode is, for example, 0.05 μm when Cr is used as the electrode material and the film is formed by the sputtering method.
The thickness is about 0.2 μm, and the formed Cr thin film is patterned using a photoresist to form an electrode. The electrode material and the patterning method are not limited to these methods.

After forming the address electrode 8 having a predetermined pattern by using any of the above methods, the barrier rib 3 is formed. As the rib material, a glass paste prepared by mixing a powder of low-melting-point glass mainly containing lead oxide and a resin such as ethyl cellulose which can be removed by firing and a solvent is used, and the patterned barrier rib 3 is formed by overprinting screen printing. Form. Alternatively, the entire rib material is applied by solid screen printing, blade coating, reverse coating, etc. and dried, and then resist is applied on the entire surface, or a dry film resist is applied, and the pattern of the barrier rib 3 is exposed. Further, development and patterning are performed, and then unnecessary portions of the rib material are removed by sandblasting to form a predetermined rib shape. In either case of the screen printing method or the sandblast method, firing is performed thereafter. The height of the barrier rib to be formed is 10 μm
It is about 200 μm.

In the PDP having the shape shown in FIG. 2, it is preferable that the dielectric layer 6'is formed by using a glass paste made of low melting point glass.
The film thickness may be 1 μm to 50 μm.

Next, a method of forming the phosphor layer will be described. The PDP back plate formed above is used as an electrodeposited body, combined with a counter electrode, and arranged so as to face each other in the phosphor electrodeposition liquid of the present invention. A voltage is applied between the address electrode and the counter electrode of the electrodeposited body while stirring the phosphor electrodeposition liquid by a usual method to perform electrodeposition. After the electrodeposition is completed, the phosphor layer is formed by washing and removing the phosphor electrodeposition liquid adhered by Van der Waals force or the like.

In order to display the PDP in color, each of the phosphor electrodeposition liquids whose emission colors are red, green and blue is used, and the above phosphor layer forming method comprising an electrodeposition-washing step is repeated in sequence. Good. In addition, during electrodeposition using a red phosphor electrodeposition solution, the potential of the electrodes in the electrodeposited body that electrodeposits the green and blue phosphor electrodeposition solutions, and the electrodes in the electrodeposited body that electrodeposits the red phosphor It is preferable to apply a bias voltage having a potential opposite to that of.
Similarly, at the time of electrodeposition using a green phosphor electrodeposition solution, red and blue electrodes are electrodeposited on the electrodeposited body to which a blue phosphor electrodeposition solution is electrodeposited, and electrodeposition using a blue phosphor electrodeposition solution is also performed. Sometimes red,
By performing the electrodeposition while applying a bias voltage to the electrodes of the electrodeposited body for electrodeposition of the green phosphor electrodeposition liquid,
It is possible to prevent unnecessary deposition of the phosphor electrodeposition liquid on the electrodes.

As the front plate of the PDP shown in FIG. 1, a transparent electrode material such as ITO, SnO ₂ and ZnO is formed on a glass substrate by a vapor deposition method, a sputtering method or the like, and then the sustain electrode 4 ( Patterning is performed by 1) a method of etching using an etching solution, or (2) a method of sandblasting through a mask.

Next, since the transparent electrode alone has a high resistance value, the bus electrode 5 of metal or the like is formed on the sustain electrode. As a forming method, (1) a method of screen-printing using a conductor paste and firing, (2) forming a conductor paste layer,
Method of etching after baking, (3) Forming a mold with a resist, filling the concave portion with a conductor paste, peeling the resist and baking, (4) Patterning by photolithography using a photosensitive conductor paste And then firing, (5) metal thin film etching method (for example, Cr / C
u / Cr laminated structure) and the like. The patterning of the sustain electrodes by etching or sandblasting may be performed after the patterning of the bus electrodes.

Next, a dielectric layer 6 is formed on the electrode by using a glass paste mainly composed of low melting point glass,
Further, a front plate is manufactured by forming a protective layer made of a MgO layer by a vapor deposition method or the like.

The front plate thus produced and the back plate provided with the above-mentioned phosphor layer are put together and sealed, and then gas such as neon or xenon is sealed in the cell. An AC PDP having the structure shown in is produced.

Of course, this manufacturing method can be applied to the DC type structure shown in FIG.

[0068]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. In addition,
In the examples, "part" means "part by weight" and "%" means "% by weight".

(Example 1) (Preparation of Phosphor Electrodeposition Solution with Red Emission Color) -21-ethylhexyl methacrylate-methacrylic acid copolymer resin [2-ethylhexyl methacrylate: methacrylic acid = 85: 15 (weight ratio) ] 5 parts ・ (Y, Gd) BO ₃ : Eu (manufactured by Kasei Optonix) 15 parts ・ Tetrahydrofuran ・ 100 parts The above composition was ultrasonic homogenizer (manufactured by Nippon Seiki Seisakusho US-300T). ) Was used to dissolve the copolymer resin and to perform dispersion. Subsequently, while irradiating with an ultrasonic homogenizer, Isopar G (manufactured by Exxon Chemical Co.) 30
After adding 0 part to granulate the resin particles, tetrahydrofuran is removed using a rotary evaporator,
A phosphor electrodeposition liquid having a solid content of 5% was obtained.

(Production of Phosphor Electrodepositing Solution with Green Emission Color) ・ 21-ethylhexyl methacrylate-methacrylic acid copolymer resin [21-ethylhexyl methacrylate: methacrylic acid = 85: 15 (weight ratio)] ... 5 Part ・ Zn ₂ SiO ₄ : Mn (manufactured by Kasei Optonix Co., Ltd.) ・ ・ ・ 15 parts ・ Tetrahydrofuran ・ ・ ・ 100 parts The above composition was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho Co., Ltd.), The copolymer resin was dissolved and dispersed. Subsequently, while irradiating with an ultrasonic homogenizer, Isopar G (manufactured by Exxon Chemical Co.) 30
After adding 0 part to granulate the resin particles, tetrahydrofuran is removed using a rotary evaporator,
A phosphor electrodeposition liquid having a solid content of 5% was obtained.

(Preparation of Phosphor Electrodepositing Solution with Blue Emission Color) 2-Ethylhexyl Methacrylate-Methacrylic Acid Copolymer Resin [2-Ethylhexyl Methacrylate: Methacrylic Acid = 85: 15 (Weight Ratio)] Part ・ BaMgAl ₁₄ O ₂₃ : Eu (manufactured by Kasei Optonix Co., Ltd.) ・ ・ ・ 15 parts ・ Tetrahydrofuran ・ ・ ・ 100 parts The above composition was mixed using an ultrasonic homogenizer (US-300T manufactured by NSK). The copolymer resin was dissolved and dispersed. Subsequently, while irradiating with an ultrasonic homogenizer, Isopar G (manufactured by Exxon Chemical Co.) 30
After adding 0 part to granulate the resin particles, tetrahydrofuran is removed using a rotary evaporator,
A phosphor electrodeposition liquid having a solid content of 5% was obtained. In each of the obtained phosphor electrodeposition liquids, although the particles of the electrodeposition liquid were precipitated, they did not aggregate and were excellent in redispersibility, and the charge stability was also good.

(Production of back panel of panel) ELD-1155 (manufactured by Okuno Chemical Industries Co., Ltd.) as a base layer on a glass substrate.
And then D-59 as an address electrode on the underlayer.
0-HV-MOD [manufactured by ESL Japan Ltd.] was patterned by a screen printing method.

Then, a glass paste PLS-3550 (manufactured by Nippon Electric Glass Co., Ltd.), which is a mixture of low-melting-point glass powder mainly containing lead oxide and a binder composed of ethyl cellulose and a solvent, is used for screen printing. After laminating in a pattern by printing, baking was performed at a peak temperature of 560 ° C. to form barrier ribs having a height of 120 μm.
A back plate of the PDP shown in (1) was manufactured.

(Method for Forming Phosphor Layer) In the red phosphor electrodeposition liquid bath stirred by a water pump, the back plate prepared above was set at an interval of 5 mm, and a counter electrode was arranged so as to be parallel and opposed to the back plate. Was placed, a voltage of 500 V was applied between the red phosphor electrode as a negative electrode and the counter electrode, and electrodeposition was performed for 20 seconds. At this time, a bias voltage of +70 V was applied to the green and blue phosphor electrodes.

After completion of electrodeposition, the back plate was washed with Isopar G and then dried in an oven at 170 ° C. Subsequently, the green and blue phosphor electrodeposition liquids were similarly electrodeposited to form green and blue phosphor layers. The obtained phosphor layer was uniform, had good compactness, and was firmly attached, and its film thickness was 20 μm.

(Production of AC type PDP) After forming a transparent electrode material on a glass substrate, a sustain electrode is formed by etching, and then a bus electrode is screen-printed using a conductor paste and baked to form a bus electrode. Furthermore, the dielectric layer 6, Mg
The front plate prepared by sequentially forming the O layers was combined with the back plate prepared above and sealed, and then gas such as neon or xenon was enclosed in the cell to prepare an AC PDP.

(Example 2) (Preparation of a phosphor electrodeposition liquid having a red emission color) 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymerized citrus [2-ethylhexyl methacrylate: 2-hydroxyethyl methacrylate] = 85: 15 (weight ratio)] 5 parts · Y ₂ O _3: Eu (Kasei Optonix Co., Ltd.) ... 15 parts of zirconium naphthenate ... 4 parts toluene 80 parts the above The composition was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho), and the copolymer resin was dissolved and dispersed. Then, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged to granulate the resin particles, and then toluene was removed by a rotary evaporator to remove the fluorescent substance with a solid content of 5%. A landing liquid was obtained.

(Preparation of Phosphor Electrodeposition Solution with Green Emission Color) 2-Ethylhexyl Methacrylate / 2-Hydroxyethyl Methacrylate Copolymer Resin [21-Ethylhexyl Methacrylate: 2-Hydroxyethyl Methacrylate = 85: 15 (Weight Ratio )] 5 parts BaAl ₁₂ O ₁₉ : Mn (manufactured by Kasei Optonix Co., Ltd.) 15 parts zirconium naphthenate 4 parts Toluene 80 parts The mixture was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho Co., Ltd.) to dissolve and disperse the copolymer resin. Subsequently, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged, and after granulating, toluene was removed by a rotary evaporator, and a fluorescent substance electrodeposition liquid with a solid content of 5% was used. Got

(Preparation of Phosphor Electrodeposition Solution with Blue Emission Color) 2-Ethylhexyl Methacrylate / 2-Hydroxyethyl Methacrylate Copolymer Resin [21-Ethylhexyl Methacrylate: 2-Hydroxyethyl Methacrylate = 85: 15 (Weight Ratio )] 5 parts BaMgAl ₁₄ O ₂₃ : Eu (manufactured by Kasei Optonix) 15 parts zirconium naphthenate 4 parts Toluene 80 parts The above composition, The mixture was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho Co., Ltd.) to dissolve and disperse the copolymer resin. Subsequently, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged and granulated, and then toluene was removed by a rotary evaporator to obtain a phosphor having a solid content of 5%. An electrodeposition liquid was obtained. The thus obtained phosphor electrodeposition liquid was excellent in redispersibility without agglomeration but precipitation of the electrodeposition liquid particles was generated, and was also good in charging stability.

(Fabrication of Panel Rear Plate) After forming the address electrodes in Example 1, as shown in FIG. 2, a dielectric layer 6 ′ was formed into a glass paste containing low melting point glass as a main component [Nippon Electric Glass Co., Ltd.]. Manufactured by trade name PLS-3232] to form a barrier rib having a film thickness of 30 μm, and barrier ribs were formed in the same manner as in Example 1.

(Method of Forming Phosphor Layer) The back plate prepared above was placed in a blue phosphor electrodeposition bath stirred by a water-jet pump, the interval was 5 mm, and the counter electrodes were parallel and opposed to the back plate. After arranging, a voltage of 500 V was applied between the counter electrode and the blue phosphor electrode as a negative electrode, and electrodeposition was performed for 30 seconds. At this time, a bias voltage of +550 V was applied to the green and blue phosphor electrodes. After the electrodeposition was completed, the back plate was washed with Isopar G and then dried in an oven at 170 ° C. Subsequently, electrodeposition solutions for green and red phosphors were similarly electrodeposited to form green and blue phosphor layers. The obtained phosphor layer is uniform and has a good compactness,
It was firmly attached and its film thickness was 10 μm. Using this back plate, in the same manner as in Example 1, AC type P
DP was prepared.

Example 3 (Preparation of Phosphor Electrodeposition Solution with Red Emission Color) 2-Ethylhexyl Methacrylate / 2-Hydroxyethyl Methacrylate Copolymerized Tallow [2-Ethylhexyl Methacrylate: 2-Hydroxyethyl Methacrylate] = 85: 15 (weight ratio)] 5 parts Y ₂ O ₃ : Eu (manufactured by Kasei Optonix) 15 parts red inorganic pigment (TOR manufactured by Dainichiseika Co., Ltd.) 0.3 part ・ Zirconium naphthenate ・ ・ ・ 4 parts ・ Toluene ・ ・ ・ 100 parts The above composition was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho) to dissolve and disperse the copolymer resin. I went. Then, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged to granulate the resin particles, and then toluene was removed by a rotary evaporator to remove the fluorescent substance with a solid content of 5%. A landing liquid was obtained.

(Preparation of Phosphor Electrodeposition Solution with Green Emission Color) 2-Ethylhexyl Methacrylate / 2-Hydroxyethyl Methacrylate Copolymer Resin [21-Ethylhexyl Methacrylate: 2-Hydroxyethyl Methacrylate = 85: 15 (Weight Ratio )] 5 parts BaAl ₁₂ O ₁₉ : Mn (manufactured by Kasei Optonix Co., Ltd.) 15 parts Green inorganic pigment (TM Green # 3340 manufactured by Dainichiseika Co., Ltd.) 3 parts ・ Zirconium naphthenate ・ ・ ・ 4 parts ・ Toluene ・ ・ ・ 100 parts The above composition was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho Co., Ltd.) to dissolve the copolymer resin and disperse it. went. Subsequently, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged, and after granulating, toluene was removed by a rotary evaporator, and a fluorescent substance electrodeposition liquid with a solid content of 5% was used. Got

(Preparation of Phosphor Electrodeposition Solution with Blue Emission Color) 2-Ethylhexyl Methacrylate / 2-Hydroxyethyl Methacrylate Copolymer Resin [21-Ethylhexyl Methacrylate: 2-Hydroxyethyl Methacrylate = 85: 15 (Weight Ratio )] 5 parts BaMgAl ₁₄ O ₂₃ : Eu (manufactured by Kasei Optonix Co., Ltd.) 15 parts Blue inorganic pigment (TM Blue # 3450 manufactured by Dainichiseika Co., Ltd.) 3 parts ・ Zirconium naphthenate ・ ・ ・ 4 parts ・ Toluene ・ ・ ・ 100 parts The above composition was mixed using an ultrasonic homogenizer (US-300T manufactured by Nippon Seiki Seisakusho Co., Ltd.) to dissolve the copolymer resin and disperse it. went. Subsequently, while irradiating with an ultrasonic homogenizer, 300 parts of Isopar H (manufactured by Exxon Chemical Co., Ltd.) was charged and granulated, and then toluene was removed by a rotary evaporator to obtain a phosphor having a solid content of 5%. An electrodeposition liquid was obtained. The thus obtained phosphor electrodeposition liquid was excellent in redispersibility without agglomeration but precipitation of the electrodeposition liquid particles was generated, and was also good in charging stability.

(Method of Forming Phosphor Layer) A back plate having the dielectric layer prepared in Example 2 was placed in a blue phosphor electrodeposition bath stirred by a water-jet pump with a space of 5 mm and parallel to the back plate. After the counter electrodes were arranged so as to face each other, a voltage of 500 V was applied between the counter electrode and the blue phosphor electrode as a negative electrode, and electrodeposition was performed for 30 seconds. Also, at this time,
A bias voltage of + 550V was applied to the green and blue phosphor electrodes. After the electrodeposition was completed, the back plate was washed with Isopar G and then dried in an oven at 170 ° C. Subsequently, electrodeposition solutions for green and red phosphors were similarly electrodeposited to form green and blue phosphor layers. The obtained phosphor layer was uniform, had good compactness, and was firmly attached, and its film thickness was 10 μm. Using this back plate, an AC PDP was produced in the same manner as in Example 1.

[0086]

INDUSTRIAL APPLICABILITY The phosphor electrodeposition liquid of the present invention has excellent charge stability and redispersibility in the electrodeposition liquid.
Not only in the case of direct electrodeposition on the exposed electrode, but also in the case of electrodeposition via the dielectric layer, it is possible to form a uniform phosphor layer having excellent adhesiveness, high packing density and high filling density. Further, the phosphor layer forming method of the present invention makes it possible to maintain stable electrodeposition conditions, improve the packing density of the obtained phosphor layer, and form a uniform phosphor layer. INDUSTRIAL APPLICABILITY The present invention is useful for forming a phosphor layer in a plasma display panel, a fluorescent display tube, a cathode ray tube, a cathode ray tube and the like.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining an AC type plasma display panel formed using the phosphor electrodeposition liquid of the present invention.

FIG. 2 is a sectional view for explaining another example of an AC type plasma display panel formed by using the phosphor electrodeposition liquid of the present invention.

3A and 3B are views for explaining a DC type plasma display panel formed by using the phosphor electrodeposition liquid of the present invention, in which FIG. 3A is a plan view and FIG. 3B is a sectional view.

[Explanation of symbols]

1 and 11 are front plates, 2 and 22 are back plates, 3 and 16 are barrier ribs, 4 are sustain electrodes, 5 are bus electrodes, 6 and 6'are dielectric layers, 7 is a MgO layer, 8 is address electrodes, and 9 are address electrodes. , 22 is a phosphor layer, 10 is a base layer, 13 is a cathode, 14 is an electrode body,
15 is a display anode, 17 is a discharge cell, 18 is a terminal portion, 19
Is a resistor, 20 is an auxiliary electrode, 21 is an electrode body, and 23 is a priming slit.

Claims (3)

[Claims] 1. A phosphor electrodeposition liquid in which resin particles containing an inorganic phosphor are dispersed in an electrically insulating edge dispersion medium. 2. The resin particles containing an inorganic phosphor are copolymer resin particles, and the copolymer resin particles have a core portion insoluble or swelling in the electrically insulating dispersion medium, The phosphor electrodeposition liquid according to claim 1, which is dispersed in such a state that it encloses the core portion and has an outer edge portion that swells or dissolves in an electrically insulating dispersion medium. 3. Electrophoresis is performed by disposing an electrodeposited body on which an electrode is arranged and a counter electrode in an electrodeposition liquid in which resin particles containing an inorganic phosphor are dispersed in an electrically insulating edge dispersion medium. Due to
A method for forming a phosphor layer, which comprises forming a phosphor layer by electrodepositing resin particles containing an inorganic phosphor on an electrodeposited body.