JPH06338254A - Manufacture of shadow mask - Google Patents

Abstract

PURPOSE:To prevent enlargement of a hole diameter on the smaller hole side by forming a corrosion-resistant film which restricts generation of defects, and which has a sufficient acid resistance. CONSTITUTION:Photoresist is applied, a pattern is formed, a certain degree of etching is performed, and a second corrosion-resistant material 5 is provided on the smaller hole surface side. For this second corrosion-resistant material 5, that of a viscosity of 20-40cp when it is liquid, which is lower than that of normally used corrosion-resistant material, is used, and the corrosion-resistant material is applied on the smaller hole surface side to be thinner than that in a normal process for facilitating defoaming at the time of drying, so generation of defects to be formed in applying the second corrosion-resistant material is prevented. In addition, a corrosion-resistant film is applied on it, etching is performed again, and all the corrosion-resistant material is eliminated for completion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a shadow mask which is a metal plate used for a cathode ray tube of a color television, for example.

[0002]

2. Description of the Related Art A method of manufacturing a commonly used shadow mask will be described. A general cathode ray tube is composed of an electron gun, a shadow mask, and three-color dot fluorescent screens of red, green, and blue. The shadow mask is a thin iron-based material attached at a distance in front of the fluorescent screen, and a large number of holes through which electron beams pass are regularly arranged. One hole corresponds to three pairs of red, green, and blue phosphor dots, and the shadow mask serves to guide the three electron beams emitted from the electron gun to each phosphor dot. . The hole diameter of the shadow mask, which is called high definition, is 0.10 to 0.15 mm (pitch 0.3 m
m), and 0.07 for ultra high definition
~ 0.09 mm (pitch 0.2 mm). On the other hand, a plate thickness of about 0.1 to 0.2 mmt is used for maintaining the strength of the shadow mask and suppressing thermal expansion. Also, the number of holes in the shadow mask increases with the increase in size, and it is usually about 300,000 at 20 inches, whereas the number of holes at 37 to 43 inches is as high as high definition, on the order of 1 million. Become.

As a method of manufacturing a shadow mask such as an ultra-high definition shadow mask in which minute holes are formed, usually, as shown in FIGS. 7 to 11, after forming a desired pattern with the first corrosion-resistant material 2, (See FIG. 7) After performing etching to a certain extent with an etching solution (see FIG. 8), the second corrosion resistant material 5 is provided on one surface (see FIG. 9). After that, etching is further advanced, but the second corrosion resistant material can form the fine holes 6 on the second corrosion resistant material forming surface side (see FIG. 10). Finally, a manufacturing method of removing the second corrosion resistant material and the first corrosion resistant material is used. (See Figure 11)

The material used as the second anticorrosive material is used by dissolving it in a solvent containing 1,1,1-trichloroethane as a main component for the purpose of defoaming air bubbles, in view of its drying property and flammability.

[0005]

When air bubbles generated during the formation of a corrosion resistant material such as roller coating or spray coating remain in the holes, they are cured before defoaming.
In this situation, if etching is performed from the lower side, the etching solution spreads in the space of the bubble portion at the time of penetration, causing a problem that the hole becomes larger than a predetermined hole diameter. Further, when the temperature of the etching solution is raised to 60 ° C. or higher, the resistance is extremely lowered and discoloration occurs, and finally there arises a problem of desorption and peeling.
This is a particularly important problem for manufacturing a shadow mask having a reduced hole diameter and an increased number of holes, which is accompanied by the recent increase in size and definition of the shadow mask.

Further, in recent years, 1,1,1, -trichloroethane used for dissolving the second anticorrosive material has become an environmental problem because ozone layer depletion and its toxicity are highlighted.

Next, the defects of the second corrosion resistant material will be described with reference to FIGS. 12 and 13. First, the photoresist is applied and the pattern is formed, and after etching to some extent, a second anticorrosive material is provided on the small hole surface side, and further etching is performed to obtain the desired pore diameter. If air bubbles accumulate in the hole after etching to some extent during application (see FIG. 12), a hole larger than the desired hole diameter will be formed on the small hole side during re-etching to obtain the desired hole diameter (see FIG. 13). ).

[0008]

According to the present invention, in order to solve the above-mentioned problems, a low-viscosity anticorrosive material and an anticorrosive film are used as a backing material, thereby making it possible to manufacture a high-definition shadow mask. It is something to do.

By using a low-viscosity anticorrosive material as the backing material, it is possible to prevent the small holes from expanding due to defects generated during etching.

Further, after the low-viscosity corrosion-resistant material is applied, a corrosion-resistant film, which is a protective film having corrosion resistance, is formed on the corrosion-resistant material, so that sufficient corrosion resistance on the small hole surface side can be secured.

In the step of removing the corrosion resistant film after etching,
By peeling the corrosion-resistant film in the state of the film, the treatment of the peeling liquid can be facilitated.

[0012]

According to the shadow mask manufacturing method of the present invention, by using a low-viscosity anticorrosive material as the backing material, it is possible to facilitate the defoaming of bubbles generated during the application of the anticorrosive material, and to form the anticorrosive film on the anticorrosive material. As a result, it is possible to reduce the amount of corrosion-resistant material used and ensure sufficient corrosion resistance during etching, and by doing so, it is possible to facilitate the production of high-definition and large-sized shadow masks by miniaturizing the holes and reducing hole defects. ,
It is possible to deal with environmental problems in the manufacturing process.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the drawings.

1 to 6 are sectional views showing the manufacturing process according to this embodiment. As in the conventional process, photoresist coating and pattern formation are performed as shown in FIG. 1 and, after etching to some extent, a second corrosion resistant material is provided on the small hole surface side.
The second anticorrosive material provided at this time is 20 to 4 when liquid.
Drying for forming the corrosion resistant material is performed by spraying the corrosion resistant material as shown in Fig. 2 thinner than the normal process when applying it to the small hole side, using a material with a viscosity of 0 cp, which is lower than the viscosity of the normally used corrosion resistant material. At this time, it is possible to facilitate defoaming, prevent the occurrence of defects formed when the second anticorrosive material is applied, and form the second anticorrosive material layer as shown in FIG.

Further, in order to obtain corrosion resistance during etching,
A corrosion resistant film (for example, a polyester film) is attached to the second corrosion resistant material formed in advance by using an adhesive or the like, and etching is performed again as shown in FIG. 4. As a result, the etching is completed as shown in FIG. By removing the corrosion-resistant material, the desired hole diameter as shown in FIG. 6 can be obtained.

By using the above method, it is possible to facilitate the production of an ultra-high-definition shadow mask and also enable the production of a shadow mask in consideration of environmental problems and the like.

[0017]

As described above, according to the present invention, by using a low-viscosity anticorrosive material at the time of forming the second anticorrosive material, it is possible to suppress the generation of defects on the small hole side due to air bubbles and to obtain sufficient acid resistance. By forming the corrosion-resistant film having the property, it is possible to prevent the hole diameter on the small hole side from expanding and to cope with the ultra-high definition of the shadow mask. As a result, it has become possible to make the shadow mask easy, while improving the ultra-high definition, increasing the size of the shadow mask, improving reliability and safety in environmental problems.

[0018]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an etching process using a first corrosion-resistant material layer in an embodiment of a manufacturing method of the present invention.

FIG. 2 is a cross-sectional view of a first corrosion-resistant material layer forming step in the manufacturing method of FIG.

3 is a cross-sectional view after forming a second corrosion resistant material layer in the manufacturing method of FIG.

FIG. 4 is a cross-sectional view of an etching process after forming a corrosion resistant film in the manufacturing method of FIG.

5 is a cross-sectional view after the etching step in the manufacturing method of FIG.

6 is a completed sectional view of a shadow mask in the manufacturing method of FIG.

FIG. 7 is a cross-sectional view of an etching process using a first corrosion resistant material layer in a conventional manufacturing method.

FIG. 8 is a cross-sectional view of a first corrosion-resistant material layer forming step in a conventional manufacturing method.

FIG. 9 is a cross-sectional view of an etching process after forming a corrosion resistant film in a conventional manufacturing method.

FIG. 10 is a cross-sectional view after an etching step in a conventional manufacturing method.

FIG. 11 is a completed sectional view of a shadow mask in a conventional manufacturing method.

FIG. 12 is a cross-sectional view showing a case where a bubble generation defect is caused by coating in a conventional manufacturing method.

FIG. 13 is a cross-sectional view showing a state after an etching process in the case where a bubble is generated due to coating and a defect occurs in the conventional manufacturing method.

[Explanation of symbols]

 1 Metal Plate 2 First Corrosion Resistant Layer 3 Etching Liquid 4 Second Corrosion Resistant Material 5 Second Corrosion Resistant Material Layer 6 Micropores 7 Bubbles 8 Corrosion Resistant Film

Claims (2)

[Claims] 1. A step of forming a first anticorrosive material on both sides of a metal plate in a desired pattern, a step of etching from both sides, a step of coating the anticorrosive material and then drying the second anticorrosive material only on one side. A step of forming, a step of forming a corrosion resistant film on the exposed surface of the second corrosion resistant material, and a step of etching again,
A method for producing a shadow mask, comprising a step of peeling a corrosion-resistant film and a step of dissolving and removing each corrosion-resistant material, wherein the second corrosion-resistant material has a low viscosity. 2. The method for producing a shadow mask according to claim 1, wherein the second corrosion resistant material is an acid resistant material.