JPH06333498A - Manufacture of shadow mask - Google Patents

Abstract

PURPOSE:To provide a method to manufacture a shadow mask with high precision by plating by solving bubble embracing problem wherein the bubbles are formed during a second resists film formation on a metal sheet and at the same time without carrying out etching to form fine holes with an etchant. CONSTITUTION:Shadow mask manufacturing method involves a process to form a resist film 12 of recessed-type pattern for desired fine hole formation on a metal sheet 10, a process to form a plating layer 3 in the recessed parts, and a process to paste a reinforcement film 14. Further the method involves a process to peel the metal sheet 10 and a process to remove the resists film 12 and the reinforcement film 14.

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 in the form of a metal plate, which is used by being loaded in a cathode ray tube of a television, and more particularly in a cathode ray tube of a color television.

[0002]

2. Description of the Related Art Conventional color cathode ray tubes are
Electron gun, shadow mask, red (Red), green (Gr
een) and blue (Blue).

This shadow mask is a metal plate made of a thin iron-based material, which is mounted in front of the fluorescent screen with a certain space, and is a small hole (a small hole) through which an electron beam emitted from an electron gun passes. Are regularly arranged. This one pore corresponds to three sets of red, green, and blue phosphor dots, and the shadow mask uses the three electron beams emitted from the electron gun for each phosphor dot. It plays a leading role.

Further, the hole diameter of this shadow mask is about 0.10 mm to 0.15 in what is called high definition.
mm (pitch 0.3 mm), and further, in the case of ultra high definition, it becomes approximately 0.07 mm to 0.09 mm (pitch 0.2 mm). The thickness of the shadow mask is 0.10 mm in order to suppress the mask strength and thermal expansion.
The one having a size of about 0.20 mm is used.

As a method of manufacturing this shadow mask,
For example, as shown in FIGS.
When forming pores (H) in the metal plate (20) using (E),
First, the resist film (22, 22) is formed by positioning on both sides of the metal plate (20) to form a desired pore pattern, and etching is performed from both sides with the etching solution (E) to form pores. Was.

However, in the wet etching using the etching solution (E), side etching occurs in the same direction as in the vertical direction, that is, in the lateral direction and side etching occurs. It is very difficult to open fine holes (H) having such a fine pore size with high accuracy.

Therefore, in order to prevent the above-described side etching, first, as shown in the side sectional views of FIGS. After forming a desired regular pore pattern on the resist film (22, 22) of, the etching solution (E) can be sprayed from both sides, or the etching solution (E) can be attached by a dipping method to form a metal plate. Etching is performed from the front and back surfaces of the metal plate (see FIG. 5b), and one side of the metal plate (20) is coated with a resist agent (R) by a spray method while the etching is in progress, and the second plate is dried. A resist film (12A) is provided (see FIG. 5c).

Next, the metal plate (20) is covered with a second resist film.
After starting the etching with the etching solution (E) from the opposite side of (12A), the metal plate (20) is penetrated to form fine pores (H) as shown in FIG. 5 (d). , The second resist film
By removing (12A) and the first resist film (22, 22) on the front and back surfaces, a large number of fine holes (H) are regularly formed on the metal plate (20) as shown in FIG. 5 (e). Can be manufactured.

[0009]

However, in the above-described method for producing a shadow mask, one surface of the metal plate (20) is coated with the resist agent (R) by a spray method to form a second resist film (12A). In the process of forming, the metal plate (20)
Bubbles (K) are generated when coating on one side of, and remain on the surface of the metal plate (20) during etching (the surface of the metal plate including the etching progress part), and the bubbles (K) are defoamed. While holding the bubble in front of the second resist film (1
2A) often formed (see Figure 6).

In this case, as shown in FIG. 6 (b), when the etching proceeds from the lower side, the etching solution (E) spreads in the space of the bubble (K) at the time of penetration, and a predetermined hole (H1) (FIG. 6b). (Dashed line part of Fig. 6), a larger hole (H2) (solid line part including bubbles in Fig. 6b) is formed, and only the part enclosing the bubble (K) has a large hole diameter and the uneven pores (H) are not accurate. It is a hole and becomes a defective product.

Further, in order to avoid the influence of the bubbles (K), the etching solution (E) is raised to, for example, 60 ° C. or more to accelerate the etching rate and suppress the increase of the hole diameter in the side direction. Due to the heat of the liquid (E), the resistance of the resist film to the etching liquid is lowered, the color of the resist film is changed, and the resist film is liable to be detached or peeled off.

Therefore, in the present invention, in the method of manufacturing a shadow mask, the inclusion of bubbles generated when the second resist film is formed on the metal plate is eliminated, and pores are not formed by the etching solution. Provided is a method of manufacturing a shadow mask with high precision by plating.

[0013]

According to the present invention, a concave patterned resist film (1) for forming a desired hole is formed on one surface of a metal plate (10).
2) forming step, a step of forming a plating layer (13) in the concave portion, a step of attaching a reinforcing film (14) on the plating layer, a step of peeling the metal plate, the resist A method for producing a shadow mask, which comprises a step of removing a film and a reinforcing film, wherein the shadow mask is formed by plating without using an etching solution and a second resist film.

The present invention will be described in detail. The metal plate (10)
On one side of the, the desired concave pattern resist film (1
In the step of forming 2), the resist film can be formed as a single layer (one layer), or the resist film can be formed as two or more layers (see FIGS. 2a, 2b and 2c). In addition, in the step of forming a resist film (12) having a desired concave pattern for forming holes on one surface of the metal plate, a convex pattern (15a) of the metal plate or the resin plate (15) is formed, and the convex pattern is formed. A resin agent (16) which is easy to peel off is applied on the mold pattern, a resist is applied thereon, and a metal plate (10) is placed on the resist (12) and pressed to form a concave pattern resist film ( 12) may be formed (see FIGS. 3a to 3f).

On the concave patterned resist film (12),
An alloy plating layer (13) is formed by electrolytic plating, and a reinforcing film (14) is attached to the surface thereof. A dry film was used as the reinforcing film. This film is for preventing the plating layer (13) from being broken or otherwise damaged when the metal plate (10) is peeled off.

[0016]

Since the manufacturing method of the present invention does not use an etching solution, it is possible to eliminate many defects such as unevenness and non-uniform portions generated during etching. Further, since the second resist agent (R) is not used, it is possible to eliminate the generation of bubbles during spray coating of the second resist agent.

Further, when a metal plate is used, the plate thickness is limited, but the thickness can be freely selected by plating. Further, in forming the plating layer, the shape of the holes can be freely formed. Therefore, the thickness of the shadow mask can be made thinner than the current thickness, the desired shape of the hole can be obtained, and the weight can be made lighter than that of the metal plate, so that the weight of the shadow mask can be reduced.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The manufacturing method according to the embodiment of the present invention will be described in detail with reference to the drawings. 1 (a) to 1 (e) are side sectional views showing a manufacturing process of a shadow mask in an embodiment of the present invention. 2 (a) to (c) and 3 (a) to (f)
FIG. 6 is an explanatory diagram showing an example of a method of forming a resist film in a shadow mask manufacturing process.

First, as shown in FIG. 1 (a), a metal plate (10)
A resist film (12) having a concave shadow mask pattern for pores (H) is formed on the surface of the.

As an example of forming a pattern of this desired shape, as shown in FIG. 2, a one-layer method of forming a concave-shaped pattern on a resist film (12) and a resist of two or more layers As shown in FIG. 3, a method of forming a film in multiple layers, and a desired convex pattern (15A) is previously formed on a metal plate or a resin plate (15), and a Teflon-based or silicon film is formed on the convex surface. The system resin (16) is thinly applied, and then the resist (12) or the resin is applied to a desired thickness. Further, the metal plate (10) is pressed from above the resist layer (12) while applying heat. After pressing, peel off the convex pattern metal plate (15) to obtain the desired concave pattern resist film (12)
Can be formed.

Next, as shown in FIG. 1B, electrolytic plating is performed on the surface of the metal plate on which the pattern is formed. When performing this plating, the metal plate (10) is connected to the negative electrode (cathode) to form the alloy plating layer (13). At that time, the plating layer cannot be formed on the pattern forming portion unless electrical continuity with the metal plate is obtained. Therefore, in order to obtain continuity even after peeling the metal plate (15) on which the convex pattern is formed, the resist is previously subjected to plasma etching or permanganate treatment.

After electrolytic plating, a reinforcing film (14) is attached to protect the plating layer (13) as shown in FIG. 1 (c). As this film, for example, a dry film or the like is suitable. Then, as shown in FIG. 1 (d), the metal plate (10) is peeled off, and then the reinforcing film (14) and the patterned resist film (12) are thinned with an alkaline aqueous solution such as caustic soda. Then, as shown in FIG. 1 (e), a shadow mask in which a large number of pores (H) formed by plating were regularly arranged was obtained.

[0023]

According to the present invention, by forming the shadow mask by plating, the etching step can be omitted, and since the second resist agent is not used, the generation of defective products due to bubbles is remarkably improved. Also, by forming the shadow mask by plating, it is possible to freely control the thickness and pore shape of the shadow mask, making it thinner, lighter, and free of hole shape, and manufacturing a highly accurate shadow mask. can do.

[Brief description of drawings]

1A to 1E are side cross-sectional views showing an example of a method for manufacturing a shadow mask in an embodiment of the present invention.

2A to 2C are side sectional views showing an example of a method for forming a resist film in a shadow mask manufacturing process.

3A to 3F are side sectional views showing another example of a method of forming a resist film in a shadow mask manufacturing process.

FIG. 4A to FIG. 4D are explanatory views showing an example of a conventional shadow mask manufacturing method.

5A to 5E are explanatory views showing another example of the conventional method for manufacturing a shadow mask.

6A and 6B are explanatory views showing an example of a method of forming pores in a conventional shadow mask manufacturing method.

[Explanation of symbols]

 10, 20 ... Metal plate 12, 22 ... Resist film 12A ... Second resist layer 13 ... Plating layer 14 ... Reinforcing film 15 ... Metal plate or resin plate having convex pattern 16 ... Resin agent E ... Etching liquid (etchant ) H ... Pores K ... Bubbles P ... Heat press R ... Resist agent

Claims (5)

[Claims] 1. A step of forming a resist film in a concave pattern for forming desired holes on one surface of a metal plate, a step of forming a plating layer in the concave part, and a reinforcing film on the plating layer. And a step of peeling off the metal plate, and a step of removing the resist film and the reinforcing film. 2. The plating layer of the concave portion forms an alloy plating layer by electrolytic plating.
A method for manufacturing a shadow mask according to. 3. A method of forming a resist film having a desired concave pattern for forming holes on one surface of the metal plate, wherein the resist film is formed as a single layer, and a resist film having at least two or more layers is formed. It is formed in
A method for manufacturing a shadow mask according to. 4. A convex pattern is formed on a metal plate or a resin plate in a step of forming a resist film having a desired concave pattern for forming holes on one surface of the metal plate, and is peeled off on the convex pattern. 2. The shadow according to claim 1, wherein an easy resin agent is applied, a resist is applied on the resin agent, and a metal plate is placed on the resist and pressed to form a concave patterned resist film. Mask manufacturing method. 5. The method of manufacturing a shadow mask according to claim 1, wherein a dry film which is easily peeled off is used as the reinforcing film in the step of peeling the metal plate after the reinforcing film is attached.