JPH08287849A - Panel for cathode-ray tube and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide an excellent reflection preventing property and resolution by forming SiO2 film having irregularities on the outer surface of a panel. CONSTITUTION: Solution including SiO2 is blown to the outer surface of a panel for forming SiO2 film comprising fine SiO2 particles 13 and having a lot of irregularities. A circumferential edge part 14 of each SiO2 particle is protruded, while a center part 15 is flat, and the difference between the circumferential edge part 14 and the center part 15 is 400Å or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a panel for a cathode ray tube which has excellent antireflection property and resolution.

[0002]

2. Description of the Related Art A cathode ray tube panel has a mirror surface on its outer surface when no treatment is applied to its outer surface. In a cathode ray tube using such a panel, light rays from the outside are reflected on the panel. There is a problem that the image reflected on the outer surface and reflected on the panel becomes difficult to see.

Therefore, for the purpose of preventing reflection of external light, a cathode ray tube has been proposed in which the outer surface of the panel is subjected to a large number of irregularities. In such a cathode ray tube, a large number of irregularities formed on the outer surface of the panel scatter the reflection of external light on the surface of the panel, thereby reducing specular reflection and reducing reflection of external light.

To form irregularities on the outer surface of the panel, there is a method of making the outer surface rough by directly forming irregularities on the panel glass by mechanical or chemical means such as honing or frosting. However, the honing process has a drawback that it is impossible to reproduce and the quality is not stable because an abrasive is sprayed on the outer surface of the panel to grind the glass to make unevenness. Further, in the frosting process, since the glass is etched with hydrofluoric acid to form irregularities, it is not possible to reproduce it, and there is a problem in handling safety and pollution associated with the use of hydrofluoric acid.

Therefore, in order to solve such a problem, a solution containing SiO ₂ particles is sprayed on the outer surface of the panel so that a large number of irregularities made of SiO ₂ particles are exhibited.
A cathode ray tube having an iO ₂ coating has been proposed.

[0006]

However, in a conventional cathode ray tube having a SiO ₂ coating formed thereon, while reflection of external light can be prevented, image rays forming an image projected on the panel constitute the SiO ₂ coating. There is a problem in that the resolution, which is most important for the cathode ray tube, is remarkably lowered because it is diffused by the SiO ₂ particles.

FIGS. 4 and 5 are enlarged cross-sectional views of SiO ₂ particles constituting a conventional SiO ₂ coating. Conventional Si
As shown in FIG. 4, the SiO ₂ particles 20 forming the O ₂ film have a bowl-like shape in which the peripheral edge portion 21 is raised and the central portion 22 is smoothly recessed from the peripheral edge portion 21, or As shown in FIG. 5, it has a hemispherical shape that bulges from the peripheral edge portion 21 toward the central portion 22.
_The SiO ₂ coating composed of the _two particles 20 has a large number of irregularities as a whole. However, the central part 2 of FIG.
2 or the surface of the SiO ₂ particle 20 in FIG. 5 has a spherical surface, the image light rays transmitted from the phosphor on the inner surface of the panel are diffused by the lens effect on the spherical surface of the SiO ₂ particle 20. As a result, the resolution of the cathode ray tube decreases. Therefore, in the conventional cathode ray tube in which the SiO ₂ coating is formed on the outer surface of the panel, there is a problem that the resolution must be remarkably lowered in order to obtain excellent antireflection property.

Therefore, an object of the present invention is to provide a cathode ray tube panel which is provided with an uneven SiO ₂ coating on the outer surface of the panel and which has excellent antireflection property and resolution, and a method for producing the same. .

[0009]

The present invention SUMMARY OF] has been made in view of the above problems and objects, SiO ₂ for spraying a solution containing SiO ₂ on the outer surface presents a large number of irregularities consisting minute SiO ₂ particles In a panel for a cathode ray tube having a film formed thereon, the periphery of each SiO ₂ particle is raised and the center is flat, and the drop between the periphery and the center is 400 Å or more. It is a panel for a cathode ray tube.

Further, in a method for manufacturing a cathode ray tube panel in which a solution containing SiO ₂ is sprayed on the outer surface to form a SiO ₂ coating film having a large number of irregularities made of fine SiO ₂ particles, the outer surface of the panel is 40 to 50. The method for producing a cathode ray tube panel is characterized in that after heating up to 0 ° C. and heating, a solution containing SiO ₂ is sprayed onto the outer surface of the panel.

The SiO ₂ coating film having a large number of irregularities formed in the present invention is not limited to the case where it is directly formed on the outer surface of the panel. For example, a conductive film formed on the outer surface of the panel or an antireflection film is used. It also includes a case where it is formed as an outermost layer film on another film such as a film.

[0012]

According to the present invention, since the central portion of each SiO ₂ particle forming the SiO ₂ coating film is flat, the image light beam passing through the central portion is diffused by the lens effect of the SiO ₂ particle. Since the light is transmitted to the outside of the panel without being disturbed, excellent resolution is obtained. In addition, the drop between the peripheral portion and the central portion of each SiO ₂ particle is 400Å
By the above, SiO ₂ composed of SiO ₂ particles
The coating film has a large number of irregularities, and the irregularities can scatter reflected light from external light to prevent external light reflection.

The reason why the drop between the peripheral portion and the central portion of the SiO ₂ particles is 400 Å or more is that if the drop is less than 400 Å, the antireflection property is lowered and the external light reflection on the panel surface is significantly increased. .

Further, according to the method for manufacturing a panel for a cathode ray tube of the present invention, after heating the outer surface of the panel to 40 to 50 ° C. and then spraying a solution containing SiO ₂ on the outer surface of the panel, SiO ₂ sprayed on the panel
The particles have a shape in which the peripheral portion is raised and the central portion is flat. The reason why the outer surface of the panel is heated to 40 to 50 ° C. is that the solution containing SiO ₂ sprayed on the panel becomes droplets and spreads at the moment when it hits the outer surface of the panel, and the peripheral portion rises to the center. Although the part is bowl-shaped, if the outer surface of the panel is lower than 40 ° C., a hemispherical or disk-shaped Si that does not drop by dropping the peripheral part after hitting the outer surface of the panel
If it is formed into O ₂ particles and the outer surface of the panel is higher than 50 ° C., the droplets of SiO ₂ are dried and solidified at the moment of hitting the outer surface of the panel, so that the peripheral edge is raised and the central portion is bowl-shaped. This is because they are formed into shaped SiO ₂ particles.

[0015]

The cathode ray tube panel of the present invention and the method for producing the same will be described below with reference to examples.

(Embodiment) FIG. 1 is a vertical sectional view of a cathode ray tube panel of the present invention.

On the outer surface of the panel glass 10, SiO presenting a large number of irregularities 11 made of fine SiO ₂ particles.
_{2 The} coating film 12 is formed.

FIG. 2 is an enlarged sectional view of SiO ₂ particles forming the SiO ₂ coating 12.

The peripheral portion 14 of each SiO ₂ particle 13 is raised and the central portion 15 is flat. In addition, each SiO
The drop between the peripheral portion 14 and the central portion 15 of the _two particles 13 is 400 to 1000Å. If the drop between the peripheral portion 14 and the central portion 15 of the SiO ₂ particles 13 is 400 Å or more, S
Although the unevenness 11 sufficient to prevent reflection of external light can be exhibited as the entire iO ₂ coating film 12, the fact that the center portion 15 of the SiO ₂ particles 13 is difficult to be flattened as a result when the head is too large, In order to improve the resolution which is one of the objects of the present invention, the peripheral portion 14 of the SiO ₂ particle 13 is used.
It is considered that the upper limit value of the head between the center part 15 and the center part 15 is 1000Å.

SiO ₂ coating 1 on this panel glass 10
Formation of 2 was performed by the following method.

First, the outer surface of the panel glass 10 is washed,
After drying, the outer surface was heated to 40 to 50 ° C.

Next, the solid content of SiO _{2 is} 2.0 to 2.5%.
The ethanol solution containing SiO ₂ was sprayed onto the outer surface of the panel glass 10 by a spray coating method at a spray pressure of 2.7 kg / cm ³ . At this time, the panel glass 10
When the ethanol solution containing SiO ₂ sprayed on the outer surface of the panel glass 10 becomes a droplet and hits the outer surface of the panel glass 10, the peripheral portion 14 thereof rises and the central portion 15 has a bowl shape. 40-50 outer surface
Since it is at a temperature of ℃, it does not instantly dry, and after the peripheral part 14 is deformed to the central part 15 to flatten the central part 15, it dries and solidifies. As a result, the peripheral portion 14 is raised and the SiO ₂ particles 13 have a flat center portion.

Thereafter, the panel glass 10 was heated at 450 ° C.
By baking for 30 minutes, the SiO ₂ coating film 12 having the irregularities 11 made of the minute SiO ₂ particles 13 was formed.

In this embodiment, the ethanol solution was used as the solvent for SiO ₂ , but the present invention is not limited to this, and SiO ₂ (OR) ₄ using another solution as a solvent is also possible.

The transparent coating 12 is formed on the panel glass 1
It may be formed on another film formed on the outer surface of No. 0.

(Comparative Example) A panel glass 10 as shown in FIG. 1 was prepared, and an SiO ₂ coating film having a large number of irregularities made of fine SiO ₂ particles was formed on the outer surface thereof.

Each Si constituting the SiO ₂ film
The peripheral portion of the O ₂ particles is raised, and the central portion thereof has a bowl shape which is smoothly recessed from the peripheral portion. In addition, each Si
The drop between the peripheral portion and the central portion of the O ₂ particle is 400 to 1
It is 000Å.

The SiO ₂ film was formed on the panel glass 10 by the following method.

First, the outer surface of the panel glass 10 is washed,
After drying, the outer surface was heated to 55 to 65 ° C., and thereafter, a SiO ₂ coating film having the irregularities made of the fine SiO ₂ particles was formed by the same method as in the examples.

A measurement test was conducted on the antireflection property and the resolution of each of the cathode ray tube panels thus produced.

Regarding the antireflection property, both the examples and the comparative examples had an excellent antireflection property with a gloss value of 65%.

Regarding the resolution, each panel glass is sample-cut into a predetermined size, a light receiver is installed on the SiO ₂ film forming side of a glass sample installed vertically, and a light source is installed on the other side. The front position was set to 0 °, the light receiver was angularly moved, and measurement was performed by a variable angle transmission test in which the intensity of transmitted light at each angle was measured.

FIG. 3 shows the measurement results of the variable-angle transmitted light intensity of each cathode ray tube panel. As is clear from FIG.
The curve of the panel for a cathode ray tube of the example has a smaller skirt spread than that of the comparative example. That is, the cathode ray tube panels of the examples had a higher transmitted light intensity at a displacement angle of 0 ° than the comparative examples, and a large reduction rate of the transmitted light intensity due to the displacement angle, and had excellent resolution.

[0034]

As described above, according to the present invention, it is possible to obtain a panel for a cathode ray tube which has an excellent antireflection property and an excellent resolution.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a cathode ray tube panel according to an embodiment of the present invention.

[FIG. 2] Si constituting a SiO ₂ film of an embodiment of the present invention
It is an expanded sectional view of O ₂ particles.

FIG. 3 is a graph showing the variable-angle transmitted light intensities of the cathode ray tube panel of the present invention and the cathode ray tube panel of the comparative example.

FIG. 4 is an enlarged cross-sectional view of SiO ₂ particles forming a conventional SiO ₂ coating.

FIG. 5 is an enlarged sectional view of SiO ₂ particles constituting a conventional SiO ₂ coating.

[Explanation of symbols]

10 Panel Glass 11 Concavo-convex 12 SiO ₂ Coating 13, 20 SiO ₂ Particles 14, 21 Peripheral Part 15, 22 Central Part

Claims (2)

[Claims] 1. A solution containing SiO ₂ is sprayed on the outer surface to form a large number of irregularities made of fine SiO ₂ particles.
In a panel for a cathode ray tube on which an iO ₂ film is formed, the peripheral edge of each SiO ₂ particle is raised and the center is flat, and the drop between the peripheral edge and the center is 400 Å or more. Panel for cathode ray tube. _2. A solution containing SiO ₂ is sprayed onto the outer surface to form a large number of irregularities made of fine SiO ₂ particles.
In a method for manufacturing a panel for a cathode ray tube for forming an iO ₂ coating, the outer surface of the panel is heated to 40 to 50 ° C., and then a solution containing SiO ₂ is sprayed onto the outer surface of the panel. Panel manufacturing method.