JP3063528B2 - Manufacturing method of shadow mask - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a shadow mask used for a color picture tube, and more particularly to a method of forming an outline of a shadow mask formed on a thin metal plate.

[0002]

2. Description of the Related Art A photo-etching method is known as a method of manufacturing a shadow mask used for a color picture tube, and one example thereof will be briefly described with reference to a process flow chart of FIG. First, a degreasing treatment is performed in which a thin metal plate serving as a substrate of a shadow mask is brought into contact with an alkaline degreasing liquid to remove oil, organic dust, and the like attached to the surface of the metal plate. Next, at the time of applying the photosensitive resin in the next step, in order to easily attach the photosensitive resin to the surface of the metal plate, the metal plate is brought into contact with an acid treatment solution, so that the surface of the metal plate is planarized. Do.

Next, a negative photosensitive resin is applied to both sides of the metal plate. Next, using a pattern mask of two types of large holes and small holes in which the circular pattern portion is a light-shielding portion, the large hole pattern mask is brought into close contact with one surface of the metal plate, and the small hole pattern mask is applied to the other surface of the metal plate. Pattern exposure is performed by closely contacting the corresponding positions and irradiating ultraviolet rays to both sides at the same time, and photo-curing of the photosensitive resin in a region other than the circular pattern portion is performed.

Then, after developing with, for example, a hot water spray to remove the unexposed portion of the photosensitive resin, the remaining photosensitive resin is subjected to hardening treatment and burning. Next, primary etching is performed on both surfaces of the metal plate, and constant etching is performed on both surfaces of the metal plate. Next, a varnish is applied to the small hole side to form an etching prevention layer. Next, secondary etching is performed on the large hole side to penetrate the small hole. Next, the etching prevention layer and the photosensitive resin are removed to obtain the shape shown in FIG. Next, a portion within the outer contour line 1 is extracted from the metal plate 4 in FIG. 4 to obtain a shadow mask substrate.

Here, a perforated area 2 in FIG. 4 shows a screen portion of a shadow mask in which a large number of hole patterns are formed.
The skirt molding area 3 indicates the outer shape, and is a part molded by pressing when incorporated in a color picture tube. The outline 1 indicates the finally required outline of the shadow mask substrate.

At present, the following method can be used as a method for extracting the shadow mask substrate from the metal plate 4 shown in FIG. That is, there is a method of mechanically punching the metal plate 4 into a shape required for the shadow mask substrate using a mold.

[0007] Alternatively, a method in which the outline 1 is formed as a penetrating broken line and a non-penetrating portion is cut out with scissors using a photoetching method, or a half-etched solid line is provided on one surface of the metal plate 4. There is a method of forming a contour line 1 by providing a half-etched broken line on the other surface so as not to penetrate the above-mentioned line, and cutting an unnecessary portion of the metal plate 4 by hand or the like.

However, the above method has the following problems. For example, in a mechanical method, an unreasonable force is applied to a metal plate, causing distortion in a shadow mask substrate portion, and it takes time to make a mold. In addition, in the method of using a photoetching method and providing scissor holes in a broken line shape and using scissors to cut a non-through portion, unnecessary burrs remain in the cut portion. Also,
A method in which a solid line in a half-etched state is provided on one surface of a metal plate, and a broken line in a half-etched state is provided on the other surface so as not to penetrate the line, and cut off manually.
Since one part of the outer contour line becomes weak in strength, the substrate part falls off from the metal plate 4 by weight in the etching step,
There is a problem that the substrate portion may fall off from the metal plate 4 even with vibration during the transfer after the etching step.

[0009]

SUMMARY OF THE INVENTION An object of the present invention relates to a method of manufacturing a shadow mask used for a color picture tube, and in particular, does not have the above-mentioned problems in forming an outline of a shadow mask substrate. An object of the present invention is to provide a method of manufacturing a shadow mask.

[0010]

That is, according to the present invention, in a method of manufacturing a shadow mask used for a color picture tube, an outer contour of a shadow mask substrate portion on a thin metal plate is formed by forming a through hole and a metal plate. By forming the large hole side and the small hole side in half-etched state with broken lines alternately on the large hole side and the small hole side, the outer contour of the shadow mask substrate has a certain strength, and An object of the present invention is to solve the above-described problem by providing a method for manufacturing a shadow mask, which is formed so as to have easy breakability.

The present invention will be specifically described with reference to the drawings.
In the present invention, in order to form an outer contour of a shadow mask substrate, as shown in FIG. A rectangular contour light-shielding portion 7 having a pitch of 50 to 450 μm and a width of 30 μm
It is provided in a dashed line at 0 μm.
A rectangular contour light-shielding portion 8 having a length of 50 to 150 μm and a width of 50 μm is formed on the side in a dashed line at a pitch of 500 μm.
It is provided so as to alternate with the broken line on the large hole side.

Further, as shown in FIG. 4, in a portion where the outer contour line 1 such as the corner portion 9 and the notch portion 10 having a cut is complicated, the shadow mask substrate is cut off from the metal plate 4 by hand. Doing so may cause the shadow mask substrate to bend or break. for that reason,
In the etching step, the outline contour is half-etched in the part where the outline contour is complicated so that the shadow mask substrate is not manually cut off from the metal plate 4 in the part where the outline contour 1 becomes complicated. Instead, a solid line pattern of a complicated portion of the outer contour line is formed as a light shielding portion on two pattern masks of a large hole and a small hole so as to form a through hole instead.

By using the above pattern mask and manufacturing the shadow mask according to the manufacturing process flow of the shadow mask shown in FIG. 3, for example, as shown in FIG. 420-480 μm
In addition, oval holes in a half-etched state having a width of 140 to 150 μm are obtained in the form of broken lines with a pitch of 500 μm. The other side of the small hole pattern side B has a length of 80-1.
Oval holes in a half-etched state of 80 μm and a width of 80 to 90 μm are obtained in the form of broken lines with a pitch of 500 μm. In this way, half-etched alternately broken concave portions are obtained on the large hole side and the small hole side.

Further, as shown in FIG. 4, in a portion where the outline is complicated, such as a corner portion 9 and a notch portion 10 having a notch, the outline is not half-etched but partially formed by a metal plate. A material penetrating the large hole side and the small hole side is obtained.

Here, in the etching step, the strength of the outer contour line portion is set so that the substrate portion does not fall off from the metal plate by weight or the substrate portion does not fall off from the metal plate even by vibration during transportation after the etching step. In order to have sufficient strength to allow the shadow mask substrate to be easily separated from the metal plate by hand, the pattern mask and the optimal length and pitch of the dashed line on the metal plate are as follows. Obtained empirically from the examples.

The width of the contour line on the pattern mask is
When the value is smaller than the above set value, the amount of etching is reduced because the penetration of the etching solution is reduced, the hole is not opened well, and the strength of the outer contour line is too strong, so that the breakability is lost, and the width is large. The width of the dashed outline on the pattern mask can be set empirically from the following examples because of excessive etching, penetration of holes, and insufficient strength even in the case of half etching. Was.

[0017]

The through hole in the metal plate for the shadow mask and the half-etched broken lines on the large hole side and the small hole side of the metal plate,
By alternately providing the shadow mask on the large hole side and the small hole side, the outer contour of the shadow mask substrate has a certain strength, and the broken line portion has easy breakability, so that the shadow mask from the metal plate can be easily made manually. The substrate can be cut off.

[0018]

Embodiments of the present invention will be described below. <Example> A metal plate for a shadow mask having a thickness of 130
A shadow mask was manufactured according to the process flow of FIG. 3 using an alloy material (amber material) mainly composed of iron and nickel of μm.

Here, in the present invention, at the time of pattern exposure, as a pattern mask used for pattern exposure, in order to form an outer contour line in a large hole pattern mask,
A rectangular light-shielding portion having an outer shape of 400 μm in length and a width of 30 μm was formed in a dashed shape with a pitch of 500 μm. Also,
Similarly, the outline of the small hole pattern mask is 100 μm long.
m and a 50 μm wide rectangular light-shielding part
The light-shielding portion was formed so as to be alternately formed on the large hole side and the small hole side as shown in FIG. Further, the same line pattern was provided at a position opposite to both the large hole pattern mask and the small hole pattern mask so that the corner portion and the notch portion of the shadow mask substrate became through holes by etching.

Using the above pattern mask, a shadow mask is manufactured in accordance with the process flow of FIG. 3 and a length of 477 μm and a width of 147 μm are formed on the side of the large hole pattern as a half-etched broken line portion which becomes an outline of the shadow mask.
m, a depth of 102 μm, a pitch of 500 μm, an oval concave portion, and a small hole pattern side having a length of 131 μm and a width of 84 μm.
m, a depth of 32 μm, and a pitch of 500 μm were obtained in the form of dashed lines, respectively. The corners and notches of the outline were formed as through holes.

The outer contour of the metal plate for a shadow mask manufactured as described above had a certain strength, and the shadow mask substrate did not fall off from the metal plate during the manufacturing process. Moreover, the extraction of the shadow mask substrate portion from the metal plate can be easily performed by manually removing the unnecessary portion of the metal plate, and the unnecessary portion of the metal plate is collectively removed in a state where several metal plates are stacked. It was also possible to perform the picking manually.

[0022]

The outer contour of the metal plate for a shadow mask manufactured according to the present invention has a certain strength, and there is no defect that the shadow mask substrate portion falls off from the metal plate due to vibration during the manufacturing process. Becomes In addition, since the outer contour line is easily breakable, the shadow mask substrate portion can be easily extracted from the metal plate by manually removing unnecessary portions of the metal plate without using an instrument. Even in a stacked state, unnecessary parts of the metal plate can be collectively cut off manually, which leads to an improvement in production man-hours, and burrs occur on the side of the obtained shadow mask substrate. The present invention is practically excellent, for example, a smooth material can be obtained.

[0023]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of an outline of a shadow mask of the present invention.

FIG. 2 is an explanatory view showing an example of an outer contour portion of a shadow mask pattern mask used in the present invention.

FIG. 3 is a process flow chart showing an example of a shadow mask manufacturing process.

FIG. 4 is a plan view showing an example of a shadow mask substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outline contour line 2 Effective area 3 Skirt forming area 4 Metal plate 5 Large hole pattern mask 6 Small hole pattern mask 7 Contour light shielding part 8 Contour light shielding part 9 Corner part 10 Notch part 11 Photosensitive resin A Large hole pattern Side B Small hole pattern side

Claims (1)

(57) [Claims] In a method of manufacturing a shadow mask used for a color picture tube, an outer contour line of a shadow mask substrate portion formed on a thin metal plate is defined by a through hole and a large hole side and a small hole side of a metal plate. In the half-etched state, the outer contour of the shadow mask substrate is formed with a dashed line that alternates between the large hole side and the small hole side so that it has a certain strength, and also has easy breakability. Forming a shadow mask.