KR20040011660A - Panel for Color Cathode-ray Tube - Google Patents

Abstract

PURPOSE: A panel is provided to achieve improved luminance and contrast of color cathode ray tube, while forming a uniform phosphor screen by enhancing the dispersing ability of the phosphor. CONSTITUTION: A color cathode ray tube comprises a black matrix layer formed on the inner surface of the color cathode ray tube; and a phosphor screen formed between the black matrix layers and deposited with red, green and blue phosphors. At least one of the phosphors has a particle with a surface coated with a metal oxide film, wherein the metal oxide film is made of Fe2O3 and has a thickness of 10 to 70nm.

Description

Panel for color cathode ray tube {Panel for Color Cathode-ray Tube}

The present invention relates to a phosphor used for a screen of a color cathode ray tube, and more particularly, by forming a red pigment film, which is a selective light absorption film of a thin film on the surface of the phosphor by sputtering method, so as to have a better light transmission selectivity than that of pigment particles. The present invention relates to a color cathode ray tube panel capable of improving the dispersibility of phosphors to form a uniform fluorescent film and improving the luminance and contrast characteristics of the color cathode ray tube.

In general, a conventional color cathode ray tube attaches red pigment particles having an average diameter of 100 nm or less to the red phosphor used for forming a fluorescent surface by organic binding to reflect red regions, and absorbs other region colors. A phosphor having a function is used. And the amount of the pigment used in the above is attached to the pigment of 0.03 ~ 0.1 weight (%) relative to the amount of the phosphor.

The following is a description of the screen forming method of the color cathode ray tube.

First, the inner surface of the panel on which the black matrix is formed is washed with pure water to remove foreign substances present on the inner surface, and then a precoat liquid containing a PVA solution as a main component is applied, followed by dehydration and drying. Then, suspended green phosphor slurry such as phosphor, polyvinyl alcohol, photosensitive agent, and surfactant is applied and a coating film is formed by a rotary coating method. The finished coating film is dried using a heater, and the shadow mask is bonded to the panel to expose a predetermined position and photocured to render it insoluble in water. Subsequently, the shadow mask is separated from the panel, and then pure water is used to develop the inner surface of the panel to complete the green fluorescence layer. After forming a blue and red fluorescent film in the same manner, and then planarized on the fluorescent film using an emulsion or lacquer on the red, blue, green fluorescent film and the aluminum film is deposited to complete the screen.

In the method of attaching the pigment to the phosphor, gelatin and arivia rubber are used as binders to attach the phosphor and the pigment, and the pigment is dispersed in a phosphor dispersion in which the phosphor is dispersed in an aqueous solution of gelatin and an aqueous solution of rubber in arribia on the other side. After mixing and stirring an aqueous solution, a hardening | curing agent is added to this liquid mixture, and a mixture of gelatin and aribian rubber is used as a pigment, and it adheres to a fluorescent substance surface. The phosphor thus formed is non-uniform in adhesion of the pigment, and adheres between the phosphor and the phosphor as well as the adhesion between the pigment and the fluorescent film, thereby reducing the dispersibility of the phosphor.

In addition, when the fluorescent film of the cathode ray tube is manufactured using the phosphor formed as described above, screen quality is deteriorated by causing a decrease in the filling property of the fluorescent film and a decrease in the cutting property of the fluorescent film. It impedes the transmission of the light and the irradiation of the electron beam, which is a factor of lowering the brightness and contrast characteristics of the color cathode ray tube.

Phosphor prepared using the above method is shown in Korean Patent Laid-Open Publication No. 2000-0045832. Looking at the prior art, the pigment particles are used to increase the selectivity of light using smaller microparticles, but it is difficult to uniformly distribute the pigments, making it difficult to uniformly adhere to the surface of the phosphor, and the biggest problem is that the microparticle phosphor of 4 μm or less There is a problem that the pigment adhesion is almost impossible.

The present invention is to solve the conventional problems as described above, by forming a red pigment layer of 10 ~ 70nm thin film on the surface of the red phosphor has a high light transmittance in the red region of visible light, and has a high light absorption in other regions It is an object of the present invention to provide a panel for a color CRT that can improve luminance and contrast characteristics, which are the quality of the color cathode ray tube.

1 is a cross-sectional view showing a general sputtering method.

2 is a cross-sectional view showing a process for forming a phosphor of the present invention.

3 is a cross-sectional view of the phosphor comparing the phosphor surface state;

4 shows a phosphor reflection spectrum.

*** Explanation of symbols for the main parts of the drawing ***

1: panel 2: screen curtain

3: shadow mask 4: frame

5: Funnel 6: Neck part

7: electron gun 8: electron beam

9: deflection yoke 10: inner shield

11: black matrix layer 12: phosphor layer

13: black matrix pattern 14: metal film

15: external light reflection scheme 16: voids

Technical means of the present invention for achieving the above object, the inner surface has a constant roughness, a plurality of black matrix layer is formed on the inner surface, red, green, blue phosphor between the black matrix layer and the black matrix layer A color cathode ray tube including the coated fluorescent surface is characterized in that a metal oxide film is formed on the surface of the phosphor particles.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In general, a method of forming a coating layer on a workpiece by sputtering blows argon gas, which is an inert gas, between the target material 2, which is the cathode 1, and the workpiece 4, which is the anode 3, as shown in FIG. Applying a voltage causes a low pressure discharge to ionize the argon gas, and the ionized argon ions collide with the surface of the target material 2 charged with the cathode to release the target material atoms 5 which are coated particles. The target material atoms 5 thus released are adhered to and coated on the surface of the workpiece opposed to the anode.

The present invention does not attach the red pigment particles to the surface of the red phosphor by organic binding, but instead of depositing and oxidizing metal atoms on the surface of the phosphor by sputtering an inorganic red pigment on the red phosphor in a vacuum state as described above, the phosphor particles are used. A metal oxide film is formed on the surface of the film.

2 is a cross-sectional view showing a process of forming a phosphor by the sputtering method of the present invention.

As shown in FIG. 2, the red phosphor, which has been calcined and washed, is placed in a sputtering apparatus, and a target sample made of iron (Fe) is set on the target 6, and the internal pressure is reduced to 1 torr or less. Then, the stage 7 on which the phosphor powder is placed is shaken to cause the phosphor powder 8 to flow in the left and right directions so as to have a uniform deposition on the surface of the phosphor during sputtering. In this state, when the internal temperature is about 40 ° C., iron (Fe) atoms are popped out by sputtering argon (Ar) gas to form an iron (Fe) film on the surface of the phosphor.

The iron (Fe) film has a thickness of about 10 to 70 nm. For this reason, the film formed by the sputtering method, unlike the film formed of particles, forms a very dense film and a very strong adhesive force, so as to ensure permeability. This is because an appropriate film thickness is required.

When the red phosphor formed as described above is injected with oxygen in an electric furnace and calcined at 300 ° C., iron (Fe) on the surface of the phosphor forms a red iron oxide (Fe ₂ O ₃ ) thin film.

The above method is not only applied to the red phosphor, but also to form the iron oxide thin film on the green or blue phosphor in the same manner.

Fig. 3 is a view comparing the surface state of the red phosphor 8 formed using a conventional bind with the surface state of the phosphor of the present invention formed by sputtering.

As shown in FIG. 3, in the conventional phosphor, the adhesion process is performed in a state in which the pigment 9 and the phosphor are dispersed in water, so that particles between the phosphor and the pigment 9 may aggregate. In addition, since the adhesion method using a bind, not only the adhesion between the pigment and the fluorescent film, but also the adhesion between the pigment and the pigment, and the phosphor and the phosphor, the pigment adhesion in the water dispersion state is uneven pigment adhesion on the surface of the phosphor, so that the pigment on the surface of the phosphor It causes a difference in physical properties between the attached and unattached parts.

The difference in the physical properties thus produced decreases the dispersibility between the phosphor particles, and when the fluorescent film is manufactured, there is a problem in that the screen quality is lowered because the filling property of the fluorescent film decreases and the cutting property of the fluorescent film is poor.

In contrast, the fluorescent film of the present invention formed by sputtering has a red pigment thin film 10 formed on the surface of the fluorescent film in an atomic state, so that a thin and uniform strong thin film can be solved.

Figure 4 shows the reflection spectrum of the conventional phosphor and the phosphor of the present invention.

As shown in FIG. 4, the present invention in which the iron oxide thin film is formed has higher transmittance in the red region and higher light absorption in the visible region other than the red region as compared with the conventional method.

As such, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing the technical spirit or essential features thereof. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

As described above, the present invention forms a red pigment layer having a thin film of 10 to 70 nm on the surface of the red phosphor and has high light transmittance in the red region of visible light, and has high light absorption in other regions, so that the luminance is the quality of the color cathode ray tube. And there is an effect that can improve the contrast characteristics.

Claims (5)

In the color cathode ray tube formed with a black matrix layer on the inner surface, a fluorescent surface coated with red, green and blue phosphors between the black matrix layer and the black matrix layer, A panel for color cathode ray tubes, characterized in that a metal oxide film is formed on the surface of phosphor particles of at least one of the phosphors. The method of claim 1, The metal oxide film is a panel for color cathode ray tube, characterized in that formed on the surface of the red phosphor. The method of claim 1, The metal oxide panel is a color cathode ray tube, characterized in that the iron oxide (Fe ₂ O ₃ ). The method of claim 2, The thickness of the said metal oxide film has a range of 10-70 nm, The panel for color cathode ray tubes characterized by the above-mentioned. The method of claim 1, A panel for color cathode ray tubes, characterized in that a metal oxide film is formed on the surface of the phosphor particles by using a sputtering method.