KR100278503B1 - Phosphor Electrode Composition for Field Emission Device and Phosphor Film Manufacturing Method Using Organic Electrodeposition Method - Google Patents

Abstract

The present invention relates to a method for producing a fluorescent film using a fluorescent electrode electrodeposition composition for a field emission device and an organic electrodeposition method, by which the thickness of the fluorescent film for display is uniform and the uniformity of the film. The present invention relates to a phosphor, an anion electrodeposition resin, and a dispersion medium. It is characterized by forming a fluorescent film by using an organic electrodeposition method on the electrodeposition liquid consisting of phosphorus.

Description

Phosphor Electrode Composition for Field Emission Device and Phosphor Film Manufacturing Method Using Organic Electrodeposition Method

The present invention relates to a method for producing a fluorescent film using the electrode electrodeposition composition and the organic electrodeposition method for a field emission device by making the thickness of the display fluorescent film and the uniformity of the fluorescent film constant.

Conventional FED (Field Emission Display) devices have similarities to CRTs in that the electrons emitted from the cathode in vacuum strike the anode's fluorescent film and emit light, but the CRT emits electrons by applying a high voltage through the electron gun. Unlike the long CRT, the FED device uses electrons to be emitted by forming an electric field in hundreds of thousands of cathodes.

However, since the FED device does not have a shadow mask, unlike the CRT, the quality depends on the thickness of the fluorescent film and the uniformity of the fluorescent film. Therefore, in the FED device, it is essential to make the thickness and film uniformity of the fluorescent film constant. Although it has been studied and presented, it has not been found to have a significant effect in forming a compact fluorescent film by solving the thickness of the fluorescent film of the FED device, the uniformity of the fluorescent film, and the like.

Therefore, recently, the application of CRT has been announced since the 1950s, and has been applied to the electrophoresis method, which has also been applied to the painting of automobiles.

The electrodeposition method is not only uniform in film thickness and film concentration, but also has an advantage in that the formation rate of the fluorescent film is fast, the thickness can be easily controlled, and an irregular object can be coated (Electrochem Soc., Vol. 137, No. .7 See the Cataphoretic Deposition of Phosphor, 23340p-2340p by Ken R. Hesse et al., July 1990.

The electrodeposition method means that the electrodeposition object is moved to the negative electrode or the positive electrode using a binder dissolved in the medium, and a binder insoluble in the medium is deposited by chemical reaction at the negative electrode or the positive electrode and coated with the electrodeposition object. The electrodeposition method can be classified into organic electrodeposition method and inorganic electrodeposition method according to the kind of binder.

The conventional electrodeposition method has been used a lot of inorganic electrodeposition method, and has been using inorganic materials such as lanthanum, aluminum and magnesium as a binder used in the inorganic electrodeposition method.

However, the FED device using the inorganic electrodeposition method as described above has a problem in that the fluorescent film is unevenly formed and the adhesion is low because a low molecular weight material is used.

Therefore, the present invention was created in view of the above-mentioned problems, and an object of the present invention is a uniform electrode film composition for forming a fluorescent film, and a fast formation rate of the fluorescent film, and easy to control the thickness of the electrode electrodeposition composition and organic It is to provide a method for producing a fluorescent film using the electrodeposition method.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the organic electrodeposition method using the electrodeposition liquid composition of this invention.

<Explanation of symbols for main parts of the drawings>

2: phosphor 4: electrodeposition resin

6: anode 8: fluorescent film

10: electrodeposition tank 12: magnetic stirrer

14: Dispersant 16: Cathode

In order to achieve the object of the present invention as described above, the method for producing a fluorescent film using the phosphor electrodeposition liquid composition and electrodeposition method for the field emission device of the present invention, electrodeposition comprising a phosphor, an anion electrodeposition resin, and water as a dispersion medium It is characterized by producing a fluorescent film by an organic electrodeposition method using a liquid composition.

Forming the fluorescent film using the electrodeposition composition and the organic electrodeposition method of the present invention as described above will be described in detail as follows.

The organic electrodeposition method of the present invention is classified into cationic organic electrodeposition method and anion organic electrodeposition method depending on whether the charge of the electrodeposition resin is a cation or an anion, so long as it is a substance capable of fluorescence by an electron beam emitted from the cathode of the FED device. All is good

Representative phosphors include [ZnO: Zn], [ZnO: Ag, Cl + In ₂ O ₃ ], [ZnS: Cu, Al + In ₂ O ₃ ], [(Zn, Cd) S: Ag, Cl + In ₂ O ₃ ], [La ₂ O ₂ S: Tb ₃ ], [Gd ₂ O ₂ S: Tb], [Y ₂ O ₂ S: Eu], [ZnAlGaO ₄ : Mn], and the like.

In general, the anion electrodeposition resin is in a state in which a carboxyl group introduced into the resin skeleton is neutralized with an amine to be hydrated, and examples of the skeleton of the resin include acrylic resins, alkyd resins, polyesters, polyurethane resins, and the like. A carboxyl group is introduced into the resin skeleton, which is neutralized with an amine to impart a charge, thereby becoming an anion electrodeposition resin.

In addition, melamine resin is included as a curing agent for curing the electrodeposited membrane after the anion electrodeposition resin is electrodeposited, and such anion electrodeposition resin and curing agent may be used dissolved in a cellosolve solvent.

The anion electrodeposition resin surrounds the phosphor in the electrodeposition solution to impart a charge to the phosphor and moves to the anode when a direct current field is applied and is electrodeposited together with the phosphor on the surface of the anode.

Examples of the dispersant of the present invention include substances such as Alcosperse175 (trade name), Blancol ^, Liquid, Blancol ^, N, Colloid 226/35, Daxad ^, 23, Tween 80, Tween 60, and their chemical components are naphthalenesulfonic acid. Sodium salt, acrylic copolymer sodium salt, ammonium salt polyacrylate, alkylaryl polyethersulfonic acid sodium salt, polyethylene (4) sorbitan monolaurate, polysorbate (80), polysorbate (60) and the like.

Such a dispersant not only prevents the aggregation of the phosphor by improving the dispersion of the phosphor in the electrodeposition liquid, but also when the dispersant is anion, it has the same anion as the charge of the electrodeposition resin, thereby improving the performance of the electrodeposition resin.

As the anti-foaming agent generated when the electrodeposition solution is stirred, polyoxyethylene, polyoxyethylene copolymer, glycerol monodilaurate, acetic acid ester of monodiglyceride, etc. are used as a compound having a low HLB (Hydrophilic Liphophilic Balance) value.

Since the specific gravity of the phosphor contained in the electrodeposition liquid is about 3 to 4, which is higher than that of water, the phosphor is precipitated without stirring, so it is preferable to continuously stir the phosphor.

However, since the above-mentioned stirring is necessary, bubbles are generated during the stirring process, thereby causing defects in the fluorescent film. Thus, a small amount of the anti-foaming agent having a low HLB value is added to suppress the bubble generation, thereby obtaining a good fluorescent film.

The principle of the anion organic electrodeposition method using the electrodeposition composition as described above will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the organic electrodeposition method using the electrodeposition liquid composition of this invention.

In the electrodeposition liquid of the electrodeposition tank 7, the phosphor 2 is surrounded by an anion electrodeposition resin 4, and a dispersant 14 for dispersing the phosphor is present on the phosphor 2 and the phosphor 2 Upon application of the electric field, the electrodeposited resin of negative ions surrounding the phosphor moves to the anode 6.

At this time, the electrodeposition resin to be moved is the charge of the electrodeposition resin is lost by the following reaction is insoluble in water as a dispersion medium is precipitated on the surface of the anode to react as follows to form a fluorescent film (8).

Anode _{reaction: 2H 2 O → 4H + +} O 2 (g) + 4e -

~COO ^{- +} H + → ~ COOH

Cathode ^{reaction: 2H 2 O + 2e - →} 2OH - + H 2 (g)

_{^{H + + OH - → H 2}} O

^{2H + + 2e - → H 2} (g)

By the above reaction, oxygen is generated by the electrolysis reaction of water at the anode 6 and hydrogen is generated at the cathode 16.

In general, the display uses a glass coated with indium tin oxide (In ₂ O ₃ + SnO ₂ ) (hereinafter referred to as ITO glass), and the cathode 16 may be any conductive metal.

In the electrodeposition tank, a stirring magnetic stirrer 12 is used to prevent precipitation of the phosphor 2.

Although the anion electrodeposition resin and the antifoaming agent added to the electrodeposition liquid composition provided in the present invention can be obtained without the addition of the electrodeposited fluorescent film, it is possible to obtain a better fluorescent film by adding these compounds as described above.

Using the composition of the present invention, a fluorescent film was prepared by the anion organic electrodeposition method as in Example.

Example 1

250 g of phosphor, [ZnS: Cu, Al + In ₂ O ₃ ], was dispersed in 180 g of distilled water, and 17 cc of a sodium naphthalene sulfonic acid sodium salt aqueous solution (5% by weight) was added thereto. After stirring for 30 minutes using a magnetic stirrer 12, 60 g of a 50% by weight solution of an anionic electrodeposition resin (acrylic resin) was added.

After adding 9 cc of polyoxyethylene aqueous solution (7% by weight) to the slurry solution, a phosphor electrodeposited liquid was prepared, and then an ITO glass was connected to the anode, and an iron plate was connected to the cathode, thereby applying a DC electric field of 80V. After electrodeposition for 70 seconds, it was confirmed that a fluorescent film electrodeposited on ITO was formed by washing and drying with distilled water.

Example 2

120 g of phosphor [Y ₂ O ₂ S: Eu] was dispersed in 15 g of distilled water and stirred for 40 minutes. 70 g of anion electrodeposition resin (alkyd resin, 30 wt%) was added to the phosphor slurry to prepare an electrodeposition liquid composition. Then, an ITO glass was connected to the positive electrode and an iron plate was connected to the negative electrode. After electrodeposition for seconds, it was confirmed that the phosphor was electrodeposited on ITO glass by washing and drying with distilled water.

Therefore, due to the method for producing a fluorescent film using the phosphor electrodeposition composition and the organic electrodeposition method of the present invention, the field thickness of the fluorescent film of the FED device is uniform, the formation rate of the fluorescent film is fast, and the thickness can be easily controlled. The present invention provides a method for preparing a fluorescent film using a phosphor electrodeposition composition and an organic electrodeposition method.

Claims (6)

In constructing the phosphor electrodeposition liquid composition used in the electrodeposition method, [ZnO: Zn], [ZnO: Ag, Cl + In ₂ O ₃ ], [ZnS: Cu, Al + In ₂ O ₃ ], [(Zn, Cd) S: Ag, Cl + In ₂ O ₃ ], Phosphor, any one of [La ₂ O ₂ S: Tb ₃ ], [Gd ₂ O ₂ S: Tb], [Y ₂ O ₂ S: Eu], or [ZnAlGaO ₄ : Mn], anionic electrodeposition resin, and dispersion A phosphor electrodeposition liquid composition for a field emission device, characterized in that the electrodeposition liquid consisting of a solvent medium. The dispersant, sodium naphthalene sulfonate salt, acrylic copolymer sodium salt, ammonium polyacrylate, alkylaryl polyether sulfonate salt, sorbitan monolaurate, polysorbate 80 or polysorb A phosphor electrodeposition liquid composition for a field emission device, characterized in that it comprises at least one of the bait 60. The method of claim 1, wherein the electrodeposition liquid further comprises any one of a polyoxyethylene, a polyoxyethylene copolymer, a glycerol monodilaurate or a monodiglyceride acetate acetate having the lowest value of HLB as the anti-foaming agent. A phosphor electrodeposition liquid composition for a field emission device. The method of claim 1, wherein the anion electrodeposition resin in the electrodeposition liquid is an acrylic resin, an alkyd resin, a polyester or a polyurethane-based resin, which is obtained by introducing a carboxyl group, neutralizing it with an amine, and imparting a charge thereto. Phosphor electrodeposition liquid composition for elements. The phosphor electrodeposition composition for a field emission device according to claim 1, wherein the dispersion medium is water. A method for producing a fluorescent film using the organic electrodeposition method, wherein the fluorescent film of the FED device is formed using an anion organic electrodeposition method using the electrodeposition liquid composition of the first substrate.

Images