JP2001229846A - Tension type shadow mask and its etching treatment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tension type shadow mask for allowing wrinkling control and improving vibration resistance with uniformized tensile force on setting its frame in place and its etching treatment method. SOLUTION: A pair of buffer areas K is provided in a portion where no holes are normally formed on both sides of an open hole area T so that the buffer area extends in a direction parallel to two facing sides L1, L2 of a shadow mask SM. A plurality of through holes k are formed in the buffer area K. In addition, the open hole area T is formed in a range between the pair of the buffer areas K. Moreover, a plurality of through holes k in the buffer area K are disposed regularly while being inclined to the direction parallel to the two sides L1, L2 of the shadow mask SM.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an extended shadow mask for a color CRT and an etching method thereof.

[0002]

2. Description of the Related Art For example, in general, a color cathode ray tube is
An electron gun that emits three electron beams, a phosphor that receives the electron beam emitted from the electron gun and emits light in three primary colors, and is disposed between the phosphor and the electron gun. A plurality of round or long holes are formed to selectively pass only the electron beam in the required direction and guide it to the three primary color phosphors, and to block the electron beam in the unnecessary direction. The shadow mask is provided.
The shadow mask having a role of selectively guiding the electron beam to the phosphor is generally called a color selection mechanism, and is made of a metal thin plate having the plurality of through holes.

Here, for example, in the process of manufacturing this shadow mask, for example, 36% of nickel is used.
Strip-shaped metal sheet made of Invar-type alloy or low-carbon aluminum killed steel, etc. (hereinafter referred to as shadow mask material)
Is subjected to various processes described below in order to obtain a shadow mask that can be incorporated into a color CRT.

That is, first, a band-shaped shadow mask material manufactured by using a predetermined metal material is wound around a shaft to form a coil, and then the coil-shaped shadow mask material is sequentially unwound and longitudinally wound. By carrying out a predetermined manufacturing process using the photolithographic etching method shown below while carrying the wafer along the inside, an area (hereinafter, referred to as a product portion) inside a substantially rectangular range required as a product of the shadow mask material (hereinafter, referred to as a product portion) , A plurality of through-holes).

Here, in the manufacturing process of the shadow mask by the photolithographic etching method, first, in order to adjust the surface condition of the shadow mask material, the shadow mask material is subjected to a degreasing treatment and a smoothing process (a smoothing process). Next, a resist solution is applied to each surface (both surfaces) of the shadow mask material, and each has a thickness of about several μm (for example, 8 to 12 μm).
m) A resist film is formed (coating process), and then both surfaces of the shadow mask material are exposed to burn a predetermined through-hole pattern on the resist film (baking process). Subsequently, the resist film on the surface (both surfaces) of the shadow mask material is subjected to a development process, and a portion corresponding to the hole pattern of the resist film is removed (development step), and the resist film remains on the surface (both surfaces) of the shadow mask material. The resist film is hardened (hardening step). Next, an unnecessary resist film remaining on the surface (both surfaces) of the shadow mask material where the resist film is to be removed is removed and exposed (surface exposure step). On the shadow mask material surface (both sides)
For example, an etching solution composed of an aqueous ferric chloride solution is sprayed to etch both surfaces of the shadow mask material,
A plurality of through holes are formed in the shadow mask material (etching step), and thereafter, a resist film or the like remaining on the surface (both surfaces) of the shadow mask material is stripped (film stripping step). After that, the surface (both surfaces) of the shadow mask material is subjected to rust prevention treatment (rust prevention process), and a range including the above product portion is cut from the band-shaped shadow mask material to form a plurality of single plate-shaped shadow masks. Finally, the product portion of the single-plate-shaped shadow mask material is peeled off (stripping step) to complete the shadow mask as a product. Further, in necessary portions of the above steps, a cleaning process is appropriately performed on the shadow mask material.

In the above-mentioned etching step, an etching solution is sprayed on both sides of the shadow mask material to form a plurality of holes in the shadow mask material at once, and first, etching is performed on both surfaces of the shadow mask material. The liquid is sprayed to finish the processing before the through-hole is formed, to form a dent of a predetermined depth on both surfaces thereof, and then to form a resin (backing resin) on one surface of the shadow mask material. Is applied to close the recess (backing treatment), and then an etching solution is sprayed from a surface opposite to one surface of the shadow mask material,
There is a two-step etching method for forming a plurality of through holes in a shadow mask material.

Here, the shadow mask completed after the above-described manufacturing process of the shadow mask is completed is, for example, a substantially rectangular frame (hereinafter referred to as a frame) surrounding the through-hole region T in a color cathode ray tube. , A frame) (this kind of shadow mask is particularly called an extended shadow mask). That is, as shown in FIG. 5, the tension of the shadow mask SM is applied by the chucks 1 to 6 in the X direction along the two sides L3 and L4 facing each other and the Y direction along the two sides L1 and L2 facing each other. In the state where it is applied, it is welded and attached to the entire frame F,
Unnecessary portions outside the frame F of the shadow mask SM are removed, and the shadow mask SM is incorporated into a color CRT.

Here, the method of attaching the conventional shadow mask SM to the frame F will be described in more detail with reference to FIG. First, the chucks 1 and 3, and 2 and 4, respectively, move in the X-direction of the shadow mask SM in a direction away from each other while holding both ends of the two sides L1 and L2 of the shadow mask SM,
An X-direction tension is applied to the shadow mask SM.

From this state, the chucks 5 and 6 move in the direction away from each other with respect to the Y direction of the shadow mask SM while holding the center of the two sides L3 and L4 of the shadow mask SM. A tension in the Y direction is applied to the mask SM. At this time, the chucks 1 and 2 and the chucks 3 and 4 are movable with respect to each other in the Y direction.

Then, from this state, the shadow mask S
M is welded to the entire periphery of the frame F around the perforated region T, and then the holding of the shadow mask SM by the chucks 1 to 6 is released. Finally, unnecessary portions outside the outer peripheral portion of the frame F of the shadow mask SM are removed, and the attachment of the shadow mask SM to the frame F is completed, and this is assembled into a color CRT.

[0011]

However, in the above-mentioned conventional shadow mask SM, since the tension in the X direction of the shadow mask SM attached to the frame F is insufficient, the tension of the shadow mask SM as a whole is not uniform. As a result, there is a problem that wrinkles are generated in the shadow mask SM and the vibration resistance of the shadow mask SM is reduced.

Here, the cause of the lack of tension in the X direction of the shadow mask SM is, as shown in FIG. 5, due to the center portions of the two sides L1, L2 of the shadow mask SM (chucks 1 and 2, 3 and 4). Is not held, the central band-shaped region (shadow mask S) extending in the X direction even if tension is applied in the X direction by the chucks 1-4.
This is because a sufficient X-direction tension is not applied to the M-shaped band region including the central through-hole region T in the Y direction.

If the chucks 1 and 3 are connected to each other and the chucks 2 and 4 are connected to each other by a pair of chucks, the entire lengths of the two sides L1 and L2 are held. At first glance, the problem seems to be resolved. However, in such a case, when the tension in the Y direction is applied by the chucks 5 and 6, the two sides L1,
Since the entire area of L2 is fixedly held, a shift occurs in the shadow mask SM around the area, and wrinkles occur,
The same problem as described above occurs in that the anti-vibration characteristic of the shadow mask SM is reduced, and this does not mean that the above-mentioned problem has been solved.

Accordingly, an object of the present invention is to solve the above-mentioned technical problem and to make the tension at the time of mounting the frame of the stretchable shadow mask uniform, thereby suppressing the occurrence of wrinkles and improving the vibration resistance. An object of the present invention is to provide a shadow mask and an etching method thereof.

[0015]

According to a first aspect of the present invention, there is provided an extended shadow mask which is mounted in a color cathode ray tube in a state in which the electron beam is passed. And a plurality of defective portions are provided on both sides of the through-hole region so as to extend in a direction parallel to two opposing sides of the stretchable shadow mask. An extended shadow mask, comprising: a pair of buffer regions.

According to the present invention, the extending type shadow mask extends in a direction parallel to two sides facing each other.
A pair of buffer areas are provided on both sides of the through-hole area, where no holes are normally formed.

Here, since a plurality of defective portions are formed in the buffer area, the rigidity of the buffer area is lower than that of the surrounding area. For this reason, the buffer region has a so-called buffering action capable of absorbing the expansion and contraction (deviation) of the shadow mask. Therefore, the shadow mask is positioned near the pair of buffer regions,
While holding and extending substantially the entire two sides (hereinafter, simply referred to as two nearby sides) of the shadow mask facing each other, substantially the entire remaining two sides (hereinafter, simply referred to as the remaining two sides) other than the two nearby sides described above are held. Even if it is held and expanded, the neighborhood 2
The displacement occurring around the side can be absorbed, and the tension around the through-hole region T can be made uniform. Therefore, while maintaining almost the entire area of the four sides of the shadow mask, the shadow mask is extended in two directions orthogonal to each other.
Since the shadow mask can be attached to the frame, the tension of the shadow mask is made uniform, and the generation of wrinkles and the deterioration of the vibration resistance of the shadow mask can be prevented.

Here, the "defected portion" includes a through-hole penetrating the front and back surfaces of the shadow mask, a concave portion (dent) formed on at least one of the surfaces of the shadow mask, and the like, and includes a buffer region. Refers to a portion in which a part of a shadow mask is deleted to reduce the rigidity of the shadow mask.
The shape of the through hole and the concave portion as viewed from the shadow mask surface side may be any shape such as a square, a circle, an ellipse, and a triangle.

According to a second aspect of the present invention, in the stretchable shadow mask according to the first aspect, the through-hole region is formed in a range sandwiched by the pair of buffer regions. It is an expansion type shadow mask.

According to the present invention, the through-hole region is within a range sandwiched by the pair of buffer regions, that is, the pair of buffer regions,
It is formed in a substantially rectangular range surrounded by two line segments connecting opposite ends of each buffer region. Therefore, the entire region of the through-hole region can benefit from the buffering action of the buffer region. Therefore, it is possible to prevent the generation of wrinkles and the deterioration of the anti-vibration characteristics particularly in the through-hole region of the shadow mask.

The pair of buffer regions may be formed to be longer than the width of the through-hole region in the direction parallel to the two sides of the shadow mask, and have a length substantially the same as the two sides of the shadow mask. Most preferably, it is formed (that is, both ends of the buffer region reach the remaining two sides of the shadow mask).

According to a third aspect of the present invention, in the stretch type shadow mask according to the first or second aspect, the buffer region is a region in which the plurality of defective portions are regularly arranged. This is a stretch type shadow mask.

According to the present invention, a plurality of defective portions are regularly arranged in the buffer region. For this reason, the buffering action of the buffering area becomes almost uniform at any point in the buffering area, and as a result, the tension of the shadow mask can be made more uniform, and the generation of wrinkles and the deterioration of the vibration resistance can be prevented. .

When the defective portion is the above-described through hole, the buffer region has a so-called mesh shape. When the defective portion is the above-described concave portion, the buffer region is a golf ball. It has a shape similar to the dimple surface of the ball. Either form has the effect of making the tension of the shadow mask more uniform.

According to a fourth aspect of the present invention, in the stretchable shadow mask according to the third aspect, the arrangement direction of the plurality of defective portions in the pair of buffer regions is parallel to two opposing sides of the stretchable shadow mask. An extended shadow mask characterized by being inclined with respect to various directions.

According to the present invention, the plurality of defective portions in the pair of buffer regions are located in the vicinity of the extended shadow mask.
They are arranged inclined with respect to the direction parallel to the side. That is, a portion (bridge portion) between the plurality of defective portions is inclined with respect to the above two neighboring sides. Therefore, in either case where the shadow mask is extended in a direction parallel to the two adjacent sides or in a direction orthogonal to the two adjacent sides, the buffer region shifts. It can be absorbed and has a buffering action. Therefore, irrespective of the direction in which the shadow mask extends, the tension of the shadow mask can be made more uniform, and the occurrence of wrinkles and a decrease in vibration resistance can be prevented.

According to a fifth aspect of the present invention, there is provided a method for etching an extended shadow mask which is assembled in a state of being extended in a color cathode-ray tube. A hole etching step of forming a hole region in which a plurality of holes are formed by etching, and extending in a direction parallel to two opposite sides of the stretchable shadow mask.
A method of etching a stretchable shadow mask, comprising: a step of etching a pair of buffer regions provided on both sides of the through-hole region and having a plurality of defect portions by etching.

According to the present invention, the through hole etching step and the defective portion etching step are performed on the strip-shaped shadow mask material, so that the through hole region and the buffer region are formed in the shadow mask material by etching. For this reason, a shadow mask completed by using such an etching method can have uniform tension, less wrinkles, and excellent vibration resistance when incorporated into a color CRT.

The through hole etching step and the defective portion etching step may be performed at the same time, or may be performed at different times. The etching method may be any one of the one-step etching and the two-step etching described in the section of the related art. For example, the defective portion may be any of the above-described through hole or concave portion.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Several embodiments of the present invention for solving the above-mentioned technical problems will be described below in detail with reference to the accompanying drawings.

First, the stretchable shadow mask according to the first embodiment of the present invention will be described. FIG. 1 is a plan view schematically showing the configuration of the stretchable shadow mask according to the first embodiment of the present invention. In FIG. 1, the completed substantially rectangular shadow mask SM has a through-hole region T in which a plurality of round or long holes t for passing an electron beam are formed, and a shadow mask SM. Two sides L of
A pair of buffer regions K provided on both sides of the through-hole region T and formed with a plurality of through-holes k so as to extend in a direction parallel to L1 and L2.

As shown in detail in FIG. 2, the buffer region K has a so-called mesh shape, and one of the through holes k has a substantially square shape. Further, the plurality of through holes k are arranged at an angle of 45 degrees with respect to a diagonal direction of 45 degrees, that is, a direction parallel to the two sides L1 and L2 of the shadow mask SM. Note that FIG.
In, the four corners of the through hole k are drawn at right angles, but they are actually slightly rounded. The pair of buffer regions K is formed to be longer than the width of the through-hole region T in a direction parallel to the two sides L1 and L2 of the shadow mask SM. Strictly speaking, the shadow mask SM is formed to have almost the same length as the two sides L1 and L2, and the buffer region K
Are the remaining two of the shadow mask SM of the shadow mask.
Sides L3 and L4 have been reached.

In the first embodiment, for example, the pitch between adjacent through holes k is about 1 mm, and the length (hole width) of one side of the through hole k is 0.5 to 0.6 mm (opening). (25% to 36%), but the present invention is not limited to this, and the pitch and the hole width can be appropriately changed. However,
From the balance between the buffering action of the buffer region K and the strength of the shadow mask SM itself, the aperture ratio is preferably set to about 20 to 40%.

Next, the manufacturing process of such a shadow mask SM will be described. This shadow mask SM
A series of predetermined treatments for the band-shaped shadow mask material, for example, degreasing, leveling, coating, baking, developing, hardening, surfacing, etching, peeling, rust prevention, cutting as described in the section of the prior art. , And stripping, and the like. However, of the manufacturing steps of the shadow mask SM, the baking step and the etching step are performed in a different manner from the conventional technique.

That is, in the baking step, the transport direction (longitudinal direction) of the belt-shaped shadow mask material is
Along the through-hole region T and the resist film in the pair of buffer regions K on both sides of the through-hole region T, a pattern of a plurality of through-holes k regularly arranged as shown in FIG. Is burned. Then, the belt-shaped shadow mask material is further conveyed, and subjected to development, hardening, and surfacing steps in this order.

In the subsequent etching step, an etching solution is supplied to one or both surfaces of the strip-shaped shadow mask material, and a plurality of holes t are formed in the hole region T by etching (a hole etching step). Then, a plurality of through holes k are formed by etching in a pair of buffer regions K on both sides of the through hole region T (through hole etching step). Then, steps such as peeling, rust prevention, cutting, and stripping are sequentially performed, and the shadow mask SM as shown in FIG. 1 is completed. The through hole etching step and the through hole etching step may be performed at the same time, or may be performed at different times. Also, as the etching method,
Either one-step etching or two-step etching may be used.

Now, a procedure for welding and attaching such a shadow mask SM to the frame F will be described with reference to FIG. First, as shown in FIG. 3A, a state in which the entire area of the two sides L1 and L2 is held by the chucks C1 and C2 each extending long in the Y direction along each of the two sides L1 and L2 of the shadow mask SM. Then, the chucks C1 and C2 are moved in a direction away from each other (X direction). As a result, tension in the X direction is applied to the shadow mask SM. The lengths of the chucks C1 and C2 only need to be at least longer than the lengths of the sides F1 and F2 of the frame F substantially parallel to the sides L1 and L2 (in the Y direction). Further, it is preferable that the chucks C1 and C2 hold the buffer region K1 and a part of the buffer region K2.

Further, in a state where tension is applied in the X direction, the chucks C3 and C3 extend in the X direction in FIG. 3 along each of the two sides L3 and L4 of the shadow mask SM.
Due to C4, the center of the two sides L3 and L4 (specifically, the part from a part of the buffer area K1 to a part of the buffer area K2)
Is held, the chucks C3 and C4 are moved in a direction away from each other (Y direction). As a result, tension in the Y direction is applied to the shadow mask SM. The lengths of the chucks C3 and C4 only need to be at least longer than the lengths of the sides F3 and F4 of the frame F substantially parallel to the sides L3 and L4 (in the X direction in FIG. 3). Further, the chucks C3 and C4 preferably hold a part of the buffer area K1 and a part of the buffer area K2.

Next, the frame F is attached by welding to the back side of the shadow mask SM (the back side in FIG. 3). At this time, the entire periphery of the frame F is welded. Then, the holding of the shadow mask SM by all the chucks C1 to C4 is released. In this state, the shadow mask SM is cut off at the outer peripheral portion (sides F1 to F4) of the frame F, and unnecessary portions outside the frame F are removed.
The state shown in (b) is obtained, and it is in a form that can be incorporated into a color CRT.

Here, when the holding of the shadow mask SM is released after the entire periphery of the frame F is welded, the tensions in the X and Y directions are slightly released, and the shadow mask SM is directed toward the center thereof. A force to shrink (shrink force) acts. Due to this contraction force, the frame F may be deformed into a slightly shrunk shape at the center, that is, a so-called pincushion type. In such a case, there is a problem that the tension applied to the shadow mask SM decreases. For example, if the shadow mask SM is welded in a state where the frame F is wound in advance, the tension is reduced. The drop can be prevented.

As for the tension applied to the shadow mask SM, the tension in the X direction and the tension in the Y direction may be equal or different. For example, the tension in the Y direction may be slightly larger than the tension in the X direction. Further, in a case where heat treatment is performed after the shadow mask SM is welded and attached to the frame F, the tension decreases due to thermal expansion due to the heat treatment. May be set large in advance.

As described above, according to the shadow mask SM of this embodiment, the two sides L1 and L2 of the shadow mask SM extend in a direction parallel to the two sides L1 and L2 of the shadow mask SM. A pair of buffer regions K is provided in a portion where no hole is formed. Since a plurality of through-holes k are formed in the buffer area K, the buffer area K has a so-called buffering action capable of absorbing expansion and contraction (shift) of the shadow mask SM. Therefore, the shadow mask SM
Is held and extended over substantially the entire area of the two sides L1 and L2 near the pair of buffer areas K, and is extended while maintaining substantially the entire area of the remaining two sides L3 and L4. L2
Can be absorbed, and the tension around the through-hole region T can be made uniform. Therefore, the shadow mask SM can be attached to the frame F in a state where the shadow mask SM is extended in two directions (X and Y directions) orthogonal to each other while holding substantially the entire four sides L1 to L4 of the shadow mask SM. It is possible to prevent wrinkles of the shadow mask SM and decrease in the vibration resistance.

The shadow mask S of this embodiment is
According to M, the through-hole region T is formed in a range sandwiched between the pair of buffer regions K. Therefore, the entire region of the through-hole region T can benefit from the buffering action of the buffer region K. Therefore, in particular, the aperture region T of the shadow mask SM
It is possible to prevent the occurrence of wrinkles and a decrease in vibration-proof characteristics in the inside.

The shadow mask S of this embodiment is
According to M, a plurality of through holes k are regularly arranged in the buffer region K. For this reason, the buffering action of the buffer area K becomes almost uniform at any point in the buffer area K,
As a result, the tension of the shadow mask SM can be made more uniform, and the generation of wrinkles and the deterioration of the vibration resistance can be prevented.

The shadow mask S of this embodiment is
According to M, the plurality of through holes k are arranged to be inclined with respect to a direction parallel to the two sides L1 and L2 of the shadow mask SM. That is, a portion between the plurality of through holes k (bridge portion B in FIG. 2) is inclined with respect to the two sides L1 and L2. For this reason, the shadow mask SM has two sides L1 and L
If it is extended in the direction parallel to 2 (Y direction), or
In either case, the buffer region K can absorb the displacement, and has a buffering effect in any case where the buffer region K is extended in the direction (X direction) orthogonal to the sides L1 and L2. Therefore, irrespective of the direction in which the shadow mask SM extends, the tension of the shadow mask SM can be made more uniform, and the generation of wrinkles and the deterioration of the vibration resistance can be prevented.

Further, according to the method of manufacturing the shadow mask SM described in this embodiment, a through hole etching step in which a plurality of through holes t are formed in the through region T by etching the strip-shaped shadow mask material. And a through-hole etching step in which a plurality of through-holes k are formed by etching in a pair of buffer regions K. As a result, the through-hole region T and the buffer region K are formed.
Are etched on the shadow mask material. For this reason, the shadow mask SM completed by using such an etching method can have uniform tension, less wrinkles, and excellent vibration resistance when incorporated into a color CRT.

Although the embodiment of the present invention has been described above, the present invention can be embodied in other forms. For example, in the above-described embodiment, the through hole k penetrating the front and back surfaces of the shadow mask SM is formed in the buffer region K.
May be formed on at least one of the surfaces. Even in this case, since a part of the shadow mask SM is missing, the rigidity of the buffer region K can be reduced, and the buffer region K can have a buffering effect. It is possible to prevent generation of wrinkles and a decrease in vibration resistance. In this case, the buffer region K has a shape similar to the dimple surface of the golf ball.

The shape of the through hole k and the concave portion as viewed from the surface side of the shadow mask SM may be any shape such as a circle, an ellipse, and a triangle, in addition to the square as in the embodiment. . In any of these shapes, it is more preferable to arrange them regularly from the viewpoint of uniform buffering action. However, when high uniformity of the tension of the shadow mask SM is not required, the plurality of through holes k may be irregularly arranged.

In the above-described embodiment, the plurality of through holes k in the pair of buffer regions K are arranged at an angle of 45 degrees with respect to a direction parallel to the two sides L1 and L2 of the shadow mask SM. However, for example, two sides L1 and L
They may be arranged to be inclined at an arbitrary range of 0 to 45 degrees with respect to the direction parallel to 2. When the inclination is 0 degree,
As shown in FIG.
They are arranged in a direction parallel to the sides L1 and L2.

Further, in the above-described embodiment, each of the pair of buffer regions K has two sides L of the shadow mask SM.
1 and L2, the length is the same, but may be shorter. However, in terms of equalizing the tension, the frame F is preferably formed to be longer than the sides F1 and F2.

Further, in the above-described embodiment, the pair of buffer regions K correspond to the two sides L1, L2 of the shadow mask SM.
Is provided so as to extend in a direction parallel to the two sides L1 and L2, but the remaining two
In the vicinity of the sides L3, L4, it may be provided so as to extend in a direction parallel to the two sides L3, L4. In this case, the chucks C1 and C2 in FIG.
Holding the center of the sides L1 and L2 of the shadow mask SM,
The chucks C3 and C4 are connected to the side L3 of the shadow mask SM.
It is preferable to make changes so that the entire area of L4 can be maintained.

In addition, various design changes can be made within the scope of the matters described in the claims.

[0053]

As described above in detail, according to the stretch type shadow mask of the first aspect of the present invention, the shadow mask is stretched in two directions orthogonal to each other while maintaining almost all of the four sides of the shadow mask. In this state, it can be attached to the frame, so that it is possible to prevent the wrinkles of the shadow mask from occurring and to prevent the anti-vibration characteristics from deteriorating.

According to the stretch type shadow mask of the second aspect of the present invention, the entire area of the through-hole area can benefit from the buffering action of the buffer area. It is possible to prevent the generation of vibrations and the deterioration of the vibration resistance characteristics.

Further, according to the stretch type shadow mask of the third aspect of the present invention, the buffering action of the buffering area becomes substantially uniform at any point in the buffering area. As a result, the tension of the shadow mask is further made uniform. Further, it is possible to prevent the occurrence of wrinkles and the deterioration of the vibration resistance characteristics.

According to the stretch type shadow mask of the present invention, the tension of the shadow mask is further made uniform regardless of the direction in which the shadow mask extends.
Further, there is an effect that generation of wrinkles and a decrease in vibration resistance can be prevented.

According to the method for etching a stretchable shadow mask according to the fifth aspect of the present invention, when incorporated into a color CRT, the tension is uniform, the wrinkles are less likely to occur, and the shadow mask has excellent vibration resistance. Is provided.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a configuration of a shadow mask according to an embodiment of the present invention.

FIG. 2 shows a shadow mask according to an embodiment of the present invention.
It is a top view which shows especially the structure of a buffer area simply.

FIG. 3 is a plan view for explaining a procedure for welding and attaching a shadow mask according to an embodiment of the present invention to a frame.

FIG. 4 is a plan view schematically showing a configuration of a shadow mask according to another embodiment of the present invention, particularly, a buffer region.

FIG. 5 is a plan view for explaining a procedure for welding and attaching a conventional shadow mask to a frame.

[Explanation of symbols]

 1 to 6 chuck C1 to C4 chuck F frame F1 to F4 frame side K (K1, K2) buffer region k through hole (deleted portion) L1 to L4 shadow mask side SM shadow mask T through hole region t through hole X shadow The direction parallel to the two sides L3 and L4 of the mask Y The direction parallel to the two sides L1 and L2 of the shadow mask

Claims (5)

[Claims] 1. A stretchable shadow mask which is mounted in a state expanded in a color cathode ray tube, wherein: a through-hole region in which a plurality of through holes for passing an electron beam are formed; Provided on both sides of the through-hole region so as to extend in a direction parallel to the side,
An extended shadow mask, comprising: a pair of buffer regions in which a plurality of defective portions are formed. 2. The stretchable shadow mask according to claim 1, wherein said through-hole region is formed in a range sandwiched by said pair of buffer regions. 3. The buffer region according to claim 1, wherein the plurality of defective portions are regularly arranged.
The stretchable shadow mask according to any one of the above. 4. An arrangement direction of said plurality of defective portions in said pair of buffer regions is inclined with respect to a direction parallel to two opposite sides of said stretchable shadow mask. The stretchable shadow mask according to 1. 5. A method of etching an extended shadow mask to be incorporated in an extended state in a color cathode ray tube, wherein a plurality of through holes for passing an electron beam are formed in a strip-shaped shadow mask material. A hole etching step of forming a hole region by etching, and a pair of holes provided on both sides of the hole region so as to extend in a direction parallel to two opposite sides of the stretchable shadow mask and having a plurality of defective portions. An etching process for a stretchable shadow mask, comprising: a defective portion etching step of forming a buffer region by etching.