JP3168878B2 - 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 or the like by a photo-etching method, and more particularly to the manufacture of a high-definition shadow mask having a small opening diameter and a large number of openings. About the method.

[0002]

2. Description of the Related Art Conventionally, a shadow mask used for a color picture tube or the like is manufactured by a process as shown in FIG. That is, a metal material (hereinafter, referred to as shadow mask material 1)
A long strip-shaped metal plate supplied from a winding roll as
For example, using a low carbon steel sheet with a thickness of 0.13 mm, both sides are degreased, smoothed, and washed, and then coated and dried with a water-soluble photosensitive solution composed of casein, polyvinyl alcohol, and ammonium bichromate on both sides, and dried. A resist film 2 is formed. Next, one side of the shadow mask material 1 is exposed to the negative pattern of the small hole image, and the other side is exposed to the negative pattern of the large hole image. Thereafter, if a development process for dissolving the unexposed and uncured photoresist film with hot water is performed, as shown in FIG. 3A, a shadow mask having a small-hole resist film 2a and a large-hole resist film 2b on the front and back is formed. Material 1 is obtained.

After that, the resist film 2 is subjected to a hardening process and a burning process, and the first stage etching is performed from both front and back surfaces, followed by washing with water and drying. Using an etching solution with a Baume concentration of ferric chloride of 35 to 50,
Generally, spray etching is performed at a spray pressure of 1.5 to 3.5 kg / cm ² . In this first etching step,
As shown in FIG. 3B, it is important to stop the etching progress halfway. In the first etching step, there is also a method in which a protective film is attached to the surface of the shadow mask material 1 having the large hole resist film 2b, and the shadow mask material 1 is etched only from the small hole side.

[0004] Next, as shown in FIG. 3 (c), a resin for an etching prevention layer (hereinafter referred to as resin
Is applied, and an etching prevention layer 4 is formed which completely fills the recess 3a on the small hole side formed by the preceding etching. The surface on which the etching prevention layer 4 is formed may be on the small hole side or on the large hole side, but is often formed on the small hole side. Subsequently, as shown in FIG. 3D, a second etching step of etching the shadow mask material 1 only from the large hole side is performed, and an opening 5 penetrating from the large hole side to the small hole is formed. Finally, the etching preventive layer 4 and the resist film 2 are peeled off, washed with water and dried.
This is to obtain a flat type shadow mask 6 shown in FIG.

In the conventional method using the etching prevention layer, it can be said that the side etching phenomenon which cannot be avoided by the photo etching method is suppressed on the small hole side. That is, the etching prevention layer 4
Is filled, and the small holes are not side-etched in the second etching step, so that a precise small hole pattern in the first etching step can be maintained. Therefore, for example, it is possible to form a hole having a hole diameter smaller than the thickness of the material metal plate.

One means for applying the etching prevention layer 4 to the small holes is to use a coating roll typified by, for example, a roll coating method or a gravure coating method. That is, as shown in the example of FIG. 2, the shadow mask material 1 having the small-hole resist film 2a and the large-hole resist film 2b on the front and back is conveyed from left to right on the paper with the small-hole resist film 2a side down. The first etching is performed in one etching chamber 8, and then the substrate is washed and washed in a washing chamber 9, and then dried by heating in a drying unit 10, for example, with a heater 11. Next, a coating roll 12 having a resin 7 on its surface is brought into contact with the surface of the shadow mask material 1 on which the etching prevention layer 4 is formed, for example, the small-hole resist film 2a side, and the resin 7 is applied to the shadow mask material 1 and filled. It is. In the example of FIG. 2,
Change the rotating direction of the coating roll 12 to the shadow mask material 1.
Although the direction of rotation is opposite to the direction of travel of the shadow mask material 1, the direction of rotation may be the same as the direction of travel of the shadow mask material 1.

At this time, it is common to use an ultraviolet-curable resin or a heat-curable resin as the resin 7. That is, the shadow mask material 1 coated with the resin 7 is heated and irradiated with ultraviolet rays.
Alternatively, the resin is hardened by simply heating,
Finally, the etching prevention layer 4 is formed.

[0008]

As described above, the role of the etching prevention layer 4 is to prevent the etching solution from contacting the recess filled with the etching prevention layer in the second etching step. For this reason, it can be said that it is important that the formed etching prevention layer does not contain bubbles and that there is no application unevenness in which the applied film thickness of the etching prevention layer 4 varies depending on the portion.

That is, as shown in FIG. 4A, when there is a bubble 13 in the etching prevention layer 4 filling the small hole concave portion 3a, the opening 5 penetrating from the large hole side to the small hole in the second etching. When formed, an etchant flows into the bubbles 13 and may cause unnecessary etching of the shadow mask material 1 as shown in FIG. 4 (b). As a result, the shape of the opening may be enlarged. This may cause poor hole shape such as a predetermined circular shape.

In addition, even if there is no bubble 13 in the formed etching preventing layer 4, even if the etching preventing layer 4 has a coating unevenness, it may cause defective holes. That is, when the etching prevention layer 4 in the small hole recess 3a has a thinner portion than the desired film thickness due to uneven coating, the etchant penetrates the thin portion of the etching prevention layer 4 in the second etching, and the small hole recess 3a It can be said that it comes into contact with 3a. For this reason, unnecessary etching is performed on the small hole concave portion 3a, thereby causing a hole shape defect.

However, in the method of forming the etching prevention layer 4 using the coating roll 12 described in the section (prior art) described above, bubbles are taken in without being completely removed, and coating unevenness is likely to occur. In the shadow mask obtained, holes with poor hole shape were generated.

The present invention has been made in view of the above circumstances, and in the method of manufacturing a shadow mask, has devised a method of forming an etching prevention layer which does not cause bubbles and coating unevenness, and has reached the present invention. It is another object of the present invention to provide a method of manufacturing a shadow mask in which an opening having a defective shape does not occur in the obtained shadow mask.

[0013]

That is, according to the present invention, at least one surface of a plate-shaped metal material on which a resist film partially exposing a metal surface is formed in accordance with a predetermined pattern on both surfaces is etched. After forming a concave portion on at least one of the metal exposed portions of the surface, washing and washing with water, a first etching step of performing drying, and applying a resin to one surface having the concave portion formed in the first etching step. Filling the inside of the concave portion with a resin and curing to form an etching prevention layer; and etching the surface opposite to the surface provided with the etching prevention layer, and forming the etching prevention layer on the one surface from the opposite surface. A second etching step of forming a concave hole communicating with the formed concave portion, and a film removing step of removing the etching prevention layer and the resist film. By using a coating roll as a means for applying the resin for the etching prevention layer, by providing a means for adjusting the surface temperature of the coating roll, the temperature of the resin applied to the metal material through the surface of the coating roll The object of the present invention has been achieved by providing a method for manufacturing a shadow mask, wherein the method has a desired temperature.

The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and have noticed that the temperature of the resin 7 for the etching prevention layer varies or decreases when applied to a metal material. It was done. As shown in FIG. 2, the etching preventing layer resin 7 is stored in, for example, a coating pan 18, and is kept at a temperature of, for example, about 60 ° C. in the coating pan 18. However, before the resin 7 rides on the surface of the coating roll 12 and is applied to the shadow mask material 1 from the surface of the rotating coating roll 12, the resin 7 comes into contact with, for example, room temperature of about 23 ° C., and the temperature of the resin 7 can be said to drop. It should be noted that the range of the temperature drop of the resin 7 varies depending on the room temperature, the rotation speed of the coating roll 12, and the like.

In general, the viscosity of a resin decreases when the temperature is high, and increases when the temperature is low. Therefore, when the temperature of the resin 7 applied on the shadow mask material 1 is low, it can be said that the viscosity at the time of application is higher than a desired value. When the resin 7 is applied, the resin 7 embraces air,
Even if air bubbles 13 are generated in the concave portion 3, the resin 7 has an appropriate temperature,
That is, if the viscosity is appropriate, the air bubbles 13 often fall out of the resin 7. However, the temperature of the resin 7 decreases,
When the viscosity of the resin becomes high, the resin 7 is hardly filled in the concave portion 3, and the bubbles 13 generated in the concave portion 3 are hard to be removed from the resin 7, which may cause bubbles to be generated in the etching prevention layer 4. It was estimated.

It has also been estimated that a change in the temperature of the resin 7 and a change in the viscosity of the resin 7 may cause uneven coating.

Therefore, the present inventors adjust the temperature of the surface of the coating roll 12 when applying to the metal material, so that the temperature of the resin 7 for the etching prevention layer on the surface of the coating roll 12 can be adjusted to a desired temperature, That is, it is proposed to apply a desired viscosity to a metal material.

Next, as a modification of the above-mentioned proposal, a means for measuring the temperature of the resin 7 on the surface of the coating roll 12 is provided, and based on the measurement result obtained by the temperature measuring means, the surface of the coating roll 12 is measured. The adjustment of the temperature to a desired temperature, the use of a thermography or a laser type surface thermometer as a temperature measuring means to make the resin 7 non-contact type, and the adjustment of the surface temperature of the coating roll 12 are performed by the coating roll 12. It can also be said that performing this by passing a liquid having a predetermined temperature inside, for example, hot water, is effective as a means for solving the above problem.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a method for manufacturing a shadow mask according to the present invention will be described below with reference to the drawings. FIG.
In the above, the shadow mask material 1 is a long metal plate supplied from a take-up roll, and the first etching, rinsing, washing and drying steps are completed in accordance with the steps described in the above section (prior art). Then, as shown in FIG. 3 (b), it is assumed that concave portions are formed on both sides, and the small hole concave portion 3a side is conveyed from left to right on the paper surface with the lower surface facing downward. Next, with respect to the shadow mask material 1, using the coating roll 12,
For example, a UV-curable photo-curable resin 7 is applied.

In this embodiment, the resin 7 is put on the surface of the coating roll 12 by immersing a part of the coating roll 12 in the coating pan 18 in which the resin 7 is stored. 7 is constant at 60 ° C., for example. Next, the coating 7 is applied to the side of the small hole recess 3a by bringing the coating roll 12 having the resin 7 on the surface into contact with the lower surface of the shadow mask material 1.
In the example shown in FIG. 1, the rotation direction of the coating roll 12 is opposite to the direction in which the shadow mask material 1 is conveyed in order to increase the filling efficiency of the resin 7 into the small hole recesses 3a.

Here, as described above, the present invention adjusts the temperature of the resin 7 for the etching prevention layer on the surface of the coating roll 12 by adjusting the temperature of the surface of the coating roll 12 when applying to the metal material. A desired temperature, that is, a desired viscosity is obtained.

In FIG. 1, the inside of a coating roll 12 which is rotated by a driving means (not shown) and is made of a material having thermal conductivity such as a metal has a hollow portion. For example, hot water 16 can be filled. Then, for example, a tube 19 having the same central axis as the rotation axis of the coating roll 12 is provided,
Through 19a, for example, hot water 16 at 30 to 70 ° C. is supplied to the hollow portion inside the coating roll 12, and the hot water 16 is drained from the hollow portion by the pipe 19b.

Further, the hot water controller 15 in FIG. 1 has a temperature control means such as a heater or a cooling device.
The hot water 16 whose temperature has been adjusted thereby is supplied into the coating roll 12. After the hot water 16 is drained from the coating roll 12, it returns to the hot water controller 15,
It is used in circulation.

By passing the hot water 16 through the inside of the coating roll 12, the heat of the hot water 16 is transmitted to the surface of the coating roll 12, and the temperature of the surface of the coating roll 12 rises. As a result, the resin 7 on the surface of the coating roll 12 is warmed and the temperature is prevented from lowering, so that the desired temperature is reached when the resin 7 is applied to the shadow mask material 1. It can be said that it is desirable that the thickness of the wall of the coating roll 12 constituting the hollow portion be uniform so that the temperature of each part of the surface of the coating roll 12 heated by the hot water 16 becomes a uniform surface temperature without variation.

Next, the temperature measuring means 17 shown in FIG. 1 measures the temperature of the resin 7 on the surface of the coating roll 12. Here, when measuring the temperature, the temperature measuring means 17
If the resin 7 comes into contact with the resin 7, the resin 7 may be damaged. For this reason, the present inventors propose, as the temperature measuring means 17, means for measuring the surface temperature of the object without contacting the object with the object, such as thermography or a laser type surface thermometer. In the example of FIG. 1, a laser type surface thermometer is used as the temperature measuring means 17, and a laser beam is irradiated from the laser type surface thermometer onto the resin surface, and the reflected light is received. Is measured.

Next, the measured temperature value of the resin obtained by the temperature measuring means 17 is sent to the hot water controller 15, and when the measured temperature value is different from the desired resin temperature, the hot water controller 15 The temperature of the hot water 16 supplied to the coating roll 12 is adjusted so that the temperature of the resin 7 on the surface of the coating roll 12 becomes a desired temperature.

Next, the resin 7 is coated on the coating roll 12.
Is applied to the shadow mask material 1, the resin 7 is cured to form the etching prevention layer 4, and then the second etching and the stripping are performed, as shown in FIG. Flat shadow mask 6 shown
Is what you get.

The method of manufacturing a shadow mask according to the present invention is not limited to the embodiment shown in FIG. 1, and it goes without saying that various modifications can be made based on the spirit of the present invention. For example, although the temperature measuring means 17 is provided at one place,
It can be said that the temperature measuring means 17 may be provided at a plurality of locations in order to increase the measurement accuracy. Further, it can be said that the rotation direction of the coating roll 12 may be the same direction as the transport direction of the shadow mask material 1. In that case, temperature measurement means
The place where 17 is provided is on the opposite side in FIG. 1, that is, on the side where the resin rides on the surface of the coating roll 12.
Next, it can be said that rubber or the like may be lined on the surface of the coating roll 12 so that the surface of the coating roll 12 has elasticity.

[0029]

Embodiments of the present invention will be described below. <Embodiment> As a shadow mask material 1, a long metal plate having a thickness of 0.13 mm and a low expansion property was used, which is a long metal plate supplied from a winding roll. Next, the steps up to the first etching step were performed in accordance with the steps described in the section (prior art) described above, and a shadow mask material 1 having the concave portions 3 on the front and back as shown in FIG. 3B was obtained.

Next, as shown in FIG. 1, an ultraviolet curable resin 7 is coated on the surface of the shadow mask material 1 conveyed with the small hole concave portion 3a side down using a coating roll 12 having a diameter of 30 mm. It was applied at a thickness of 30 μm. The resin 7 supplied from the coating pan 18 onto the surface of the coating roll 12 was kept at 60 ° C. in the coating pan, and the room temperature was 23 ° C. At this time, according to the present invention, hot water 16 having a temperature of about 60 ° C. supplied from a hot water controller 15 is passed through the inside of the coating roll 12,
The resin 7 is applied to the shadow mask material 1 by placing the resin 7 on the surface of the coating roll 12 whose surface is warmed by passing water.
Is applied and filled.

Next, the temperature of the resin 7 heated by the coating roll 12 is measured by a laser type surface thermometer (manufactured by Co., Ltd.).
The measurement was carried out using a model name “IT2-60” manufactured by Keyence Corporation. That is, the surface of the resin 7 is irradiated with a laser beam, and the laser beam reflected from the surface of the resin 7 is received to measure the temperature of the surface of the resin 7.
Sent to 15.

Here, in the case of the resin 7 used in this embodiment,
Since 50 ° C. is desired as an appropriate temperature to be held at the time of applying the resin, the hot water controller 15 controls the temperature of the hot water 16 supplied to the coating roll 12 based on the measured temperature result. As a result, the temperature of the surrounding atmosphere during the application of the resin was 23 ° C., but the temperature of the resin 7 when the resin was applied to the shadow mask material 1 was kept at about 50 ° C.

Next, the ultraviolet curable resin 7 applied by the coating roll was irradiated with ultraviolet rays simultaneously with heating, so that the resin was photocured to obtain the etching preventing layer 4 shown in FIG. 3C. Next, the flat etching mask 6 was obtained by performing the second etching, the film stripping, and the like according to the steps described in the section (prior art) described above.

Next, in the shadow mask obtained in the above embodiment, as described in the above section (prior art), bubbles were generated in the resin during application of the resin, or application unevenness occurred. Was examined for poor hole shape caused by
No poor hole shape was observed.

[0035]

In the method of manufacturing a shadow mask according to the present invention, a coating roll whose surface is warmed is used as a means for applying and filling a resin for an etching prevention layer to the shadow mask material after the first etching step. The resin on the coating roll surface is heated by the temperature of the coating roll surface. In addition, the temperature of the heated resin is measured, and the temperature of the coating roll surface is adjusted based on the measurement result. As a result, the resin is applied to the shadow mask material 1 at a desired temperature.

As a result, in the shadow mask manufacturing method of the present invention, the problem that has occurred in the conventional shadow mask manufacturing method, that is, the viscosity of the resin increases due to the low temperature of the resin at the time of coating, so that the etching prevention layer It is possible to prevent the problem that air bubbles are taken in without being completely removed, and uneven application of the resin occurs, resulting in poor hole shape during etching. As a result, it can be said that the present invention is practically excellent in obtaining a high-quality and high-definition shadow mask, for example, a good-quality shadow mask can be obtained.

[0037]

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an embodiment in a method of manufacturing a shadow mask of the present invention.

FIG. 2 is an explanatory view showing a main part of an example of a conventional method for manufacturing a shadow mask.

FIGS. 3A to 3E are explanatory views showing an example of a method of manufacturing a shadow mask in the order of steps.

FIGS. 4A and 4B are explanatory views showing an example of an etching hole shape defect due to bubbles generated in a concave portion in the order of steps.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 shadow mask material 2 resist film 3 concave portion 4 etching prevention layer 5 opening 6 shadow mask 7 resin 8 etching chamber 9 washing chamber 10 drying unit 11 heater 12 coating roll 13 bubble 14 transport roller 15 hot water controller 16 hot water 17 temperature measurement Means 18 Coating pan 19 Tube

Claims (3)

(57) [Claims] At least one surface of a plate-shaped metal material on which a resist film partially exposing a metal surface is formed in accordance with a predetermined pattern on both surfaces is etched, and at least one of the metal exposed portions is exposed. After forming a concave portion, a first etching step of washing, washing and drying, and applying a resin to one surface having the concave portion formed in the first etching step, filling the inside of the concave portion with the resin, and curing the resin. Forming an etching prevention layer, and etching a surface opposite to the surface provided with the etching prevention layer to form a concave hole communicating with the concave portion formed on the one surface from the opposite surface. A method of manufacturing a shadow mask, comprising at least a second etching step and a stripping step of removing the etching prevention layer and the resist film, wherein the coating of the resin for the etching prevention layer is performed. The coating roll used as a means, means for adjusting the surface temperature of the coating roll
And the temperature of the resin on the coating roll surface
Means for measuring, obtained by the temperature measuring means
Based on the measurement results, the temperature of the coating roll surface
A method for manufacturing a shadow mask, wherein a temperature of a resin applied to a metal material through a surface of the coating roll is adjusted to a desired temperature by adjusting a temperature to a desired temperature. 2. The method according to claim 1, wherein the temperature measuring means is a thermography or a thermography.
Uses a laser-type surface thermometer, which is non-contact with resin.
2. The shadow mask according to claim 1, wherein
Production method. 3. Adjusting the surface temperature of the coating roll.
Liquid inside the coating roll at a specified temperature.
3. The method according to claim 1, wherein the step is performed by passing through.
The manufacturing method of the shadow mask of the description.