JPH10314652A - Method for applying coating liquid to metallic sheet and coating applicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to obviate the generation of air bubbles in the coating liquid packed into respective recessed parts and to form very fine through-holes of desired shapes by measuring the atmosphere temp. on the circumference of a metallic sheet formed with the plural very fine recessed parts and adjusting the temp. of this metallic sheet according to the result of the measurement. SOLUTION: A temp. sensor 30 is so disposed as to face the front surface of the metallic sheet 1 formed with the plural very recessed parts by a coating application section 14 on the side just before the metallic sheet 1 in its transporting direction and a metallic sheet heating section 32 equipped with an electric heater 34 is disposed to face the rear surface of the metallic sheet 1 within a coating booth 12. The electric heater 34 of this metallic sheet heating section 32 measures the atmosphere temp. on the circumference of the metallic sheet 1 in accordance with the detection signal from the temp. sensor 30 and the temp. of the metallic sheet 1 is so adjusted according to the result of the measurement that the specified temp. of the metallic sheet 1 is always maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for applying a coating liquid to a thin metal sheet, which fills a plurality of fine concave portions formed on the main surface of the thin metal sheet with the coating liquid. When manufacturing a shadow mask for a picture tube, an aperture grill for a Trinitron (registered trademark) tube, a lead frame for a semiconductor device, etc. by using a photo-etching method, an etching resistance layer is formed on the main surface of a thin metal plate (back side). The present invention relates to a method and an apparatus for applying a coating liquid to a metal thin plate which is preferably used when stopping.

[0002]

2. Description of the Related Art A shadow mask for a color picture tube, particularly a shadow mask for a high-resolution color picture tube, is generally formed by:
It is manufactured through a two-stage etching process. That is,
First, an etching solution is sprayed on both sides or one side from spray noise to a metal sheet on which a resist film having a predetermined pattern is formed on both main surfaces, so that it does not penetrate both sides or one side of the metal sheet. Are formed (first etching step). Next, when both surfaces of the metal sheet are etched, one surface thereof is etched, and when one surface is etched, a coating liquid such as an UV-resistant resin having etching resistance is applied to the surface where a number of concave portions are formed. After application, the coating liquid is filled into a large number of concave portions formed on one surface side, and the surface is covered with the coating liquid (backing step). Then, an etching solution is sprayed from a spray nozzle onto the surface not coated with the coating solution on the thin metal plate, and a number of concave portions formed on the surface (when both surfaces are etched in the first etching step) or a metal exposed surface. (When one side is etched in the first etching step) is etched until it communicates with the many concave portions formed on the surface side coated with the coating solution, and a large number of fine transparent members penetrating the metal sheet from the front to the back. A hole is formed (second etching step).

In the backing step in the above-described two-step etching method, a coating liquid such as a UV resin is applied to the surface of the thin metal plate on which the concave portions are formed, and a number of the concave portions are filled with the coating liquid and the surface is coated. Is coated with a coating solution, for example,
No. 33150 discloses a coating liquid coating apparatus.

In the coating apparatus disclosed in the publication, a squeegee roller composed of a smooth roller and a squeegee roller composed of a grooved roller are arranged at a distance in a conveying direction of a strip-shaped metal sheet, and three squeegee rollers are provided. Backup roller,
Each squeegee roller is disposed between the backup rollers, and the upper surface of each backup roller is positioned above a plane including both lower surfaces of the two squeegee rollers, respectively. A supply pipe for supplying the coating liquid onto the metal thin plate is disposed in front of the metal thin plate in the transport direction. In this coating apparatus, the coating liquid supplied from the supply pipe onto the thin metal plate was formed on the surface of the thin metal plate by passing the thin metal plate through the disposition position while contacting the squeegee roller formed of a smooth roller. The coating liquid supplied to the metal thin plate from the supply pipe by being filled in a number of fine concave portions and subsequently passing through the disposition position while the metal thin plate is in contact with the squeegee roller formed of the grooved roller while being in contact therewith. Is applied over the surface of the metal sheet, and the surface of the metal sheet is covered with a coating film having a predetermined thickness.

[0005]

Problems to be Solved by the Invention
When a coating liquid is applied to the surface of a metal thin plate using a coating liquid coating apparatus as disclosed in Japanese Patent Application Laid-Open Publication No. H11-107, if the temperature around the apparatus decreases in winter or the like, the temperature of the metal thin plate also decreases. When the coating liquid is applied to the surface of the thin metal sheet whose temperature has decreased, the coating liquid loses heat to the thin metal sheet, and as a result, the viscosity of the coating liquid applied to the surface of the thin metal sheet increases.

[0006] Here, as described above, the metal sheet moves while contacting the squeegee roller composed of a smooth roller, so that U supplied from the supply pipe onto the metal sheet is supplied.
When the fine recesses on the surface of the metal sheet are filled with a coating liquid such as V resin, air inside the fine recesses 2 on the surface of the metal sheet 1, as shown in FIG. Pool 3
Is pushed out of the concave portion 2 by the coating liquid 5 pushed by the squeegee roller 4 and is replaced with the coating liquid 5.
The air extruded from the concave portion 2 becomes fine bubbles 6 and mixes into the coating liquid 5 on the thin metal plate 1. At this time, if the viscosity of the coating liquid 5 is appropriately low, FIG.
As shown in (1), the air bubbles 6 mixed in the coating liquid 5 on the metal sheet 1 move in the coating liquid 5 toward the surface thereof, diffuse from the surface of the coating liquid 5 into the air, and It disappears from the upper coating solution 5.

However, as described above, as a result of the coating liquid 5 being deprived of heat by the metal sheet 1, the coating liquid 5 on the metal sheet 1 is removed.
When the viscosity increases, the bubbles 6 remain trapped in the coating liquid 5 on the thin metal plate 1, and a large number of bubbles 6 are mixed in the coating liquid 5, causing a clouding phenomenon of the coating liquid 5. Then, as shown in FIG.
Is filled with the coating liquid 5 in a state in which the bubbles 6 are kept trapped. When the etching liquid is supplied to the metal sheet 1 in the second etching step in a state in which the bubbles are trapped in the coating liquid 5 filled in the concave portion 2 on the surface of the metal sheet 1, the coating liquid 5 There is a problem that the etchant penetrates into the portion of the bubble 6 in the filled concave portion 2 and the portion that should not be etched is etched, so that a through hole having a desired shape cannot be formed.

The present invention has been made in view of the above circumstances, and when a coating liquid is applied to a main surface of a metal sheet having a plurality of fine concave portions formed thereon, the concave portion is formed. No bubbles are generated in the applied coating liquid,
Provided is a method of applying a coating liquid to a thin metal plate, which enables a fine through hole having a desired shape to be formed in the thin metal plate by etching, and a metal capable of suitably performing the coating method. An object of the present invention is to provide an apparatus for applying a coating liquid to a thin plate.

[0009]

The invention according to claim 1 is
In a method of applying a coating liquid to a metal sheet, in which a coating liquid is applied to a main surface of a metal sheet on which a plurality of fine concave portions are formed, and the concave section is filled with the coating liquid, the temperature of the metal sheet is reduced. Alternatively, an ambient temperature around the metal sheet is measured, and the temperature of the metal sheet is adjusted according to the measurement result.

According to a second aspect of the present invention, there is provided a coating liquid supply means for supplying a coating liquid to a main surface of a metal sheet having a plurality of fine concave portions formed thereon, and the main surface of the metal sheet by the coating liquid supply means. A coating liquid filling means for spreading the coating liquid supplied to the thin metal plate on the thin metal plate and filling the concave portion formed in the thin metal plate with the coating liquid. It is characterized by having temperature measuring means for measuring the temperature or the ambient temperature around the metal sheet, and temperature adjusting means for adjusting the temperature of the metal sheet in accordance with the measurement result by the temperature measuring means.

According to a third aspect of the present invention, in the coating apparatus according to the second aspect, the strip-shaped metal sheet is transported in the longitudinal direction, and the temperature measuring means is provided by the coating liquid supply means and the coating liquid filling means. In the transport direction.

According to the coating method of the first aspect,
Even if the temperature of the metal sheet decreases in winter or the like, the temperature of the metal sheet or the ambient temperature around the metal sheet is measured, and the temperature of the metal sheet is adjusted according to the measurement result. And maintained at a predetermined temperature.
Therefore, the coating liquid supplied onto the thin metal plate does not lose heat to the thin metal plate to lower the temperature and increase the viscosity of the coating liquid. Therefore, when the coating liquid supplied onto the metal sheet is filled in the concave portion formed on the surface of the metal sheet, the air that has been displaced with the coating liquid and extruded from the concave portion becomes fine bubbles. However, even if the liquid is mixed into the coating liquid on the thin metal plate, the air bubbles mixed into the coating liquid move from the coating liquid to the air as shown in FIG. 2B because the viscosity of the coating liquid is low. Spread out and disappear. Therefore, no bubbles are generated in the coating liquid filled in the concave portion on the surface of the thin metal plate.

When the coating liquid is applied to the main surface of the metal sheet by using the coating apparatus according to the second aspect of the present invention, even if the temperature of the metal sheet decreases in winter or the like, the metal is measured by the temperature measuring means. The temperature of the metal sheet or the ambient temperature around the metal sheet is measured, and the temperature of the metal sheet is adjusted by the temperature adjusting means in accordance with the measurement result by the temperature measuring means, so that the metal sheet is heated to a predetermined temperature. Will be kept. Therefore, the coating liquid supplied to the thin metal plate by the coating liquid supply means does not lose heat to the thin metal plate, so that the temperature does not decrease and the viscosity of the coating liquid does not increase. Therefore, when the coating liquid supplied onto the metal sheet is filled in the concave portion on the surface of the metal sheet by the coating liquid filling means, as described above, the coating liquid filled in the concave portion on the surface of the metal sheet. There are no bubbles inside.

In the coating apparatus according to the third aspect of the present invention, the temperature of the metal sheet or the temperature around the metal sheet at a position nearer to the metal sheet transport direction than the coating liquid supply means and the coating liquid filling means by the temperature measuring means. Since the ambient temperature is measured, the temperature before the metal sheet comes into contact with the application liquid or the application liquid filling means (squeegee roller) is measured. Accordingly, the metal sheet fed to the application position of the coating liquid is always kept at a predetermined temperature without being affected by the temperature fluctuation of the coating liquid or the temperature fluctuation of the coating liquid filling means.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIG.

FIG. 1 shows a configuration of a coating liquid coating apparatus used for carrying out a coating liquid coating method according to the present invention.
It is an outline front sectional view showing an example. This coating device 10
Although not shown, it is arranged downstream of the drying device,
From the drying device, for example, a band-shaped thin metal plate 1 which is a shadow mask material is conveyed into a coating booth 12 of the coating device 10. The metal thin plate 1 carried into the coating booth 12 has a large number of fine concave portions formed on the surface on the upper surface side.

Inside the coating booth 12, a coating processing section 1 is provided.
4 is provided.
The three backup rollers 16, 1 are spaced apart from each other in the transport direction of the metal sheet
8, 20 are provided. The thin metal plate 1 is transported in the coating booth 12 in the longitudinal direction while the lower surface side is supported by these backup rollers 16, 18, and 20. On the upper side of the transport path of the thin metal sheet 1, a first smooth roller is provided between the first backup roller 16 on the near side and the second backup roller 18 at the center in the transport direction of the thin metal sheet 1. A squeegee roller 22 is provided, and a second squeegee roller 24 composed of a grooved roller is provided between the second backup roller 18 and the third backup roller 20 at the center. The backup rollers 16, 18, 20 are arranged such that the upper surface thereof is located above a horizontal plane including the lower surfaces of the squeegee rollers 22, 24, respectively.
Are slightly downward and upward with respect to the horizontal plane. Further, the squeegee rollers 22, 2
4, discharge ports of a first supply pipe 26 and a second supply pipe 28 for supplying a coating liquid such as a UV resin onto the metal sheet 1 are provided on the near side in the transport direction of the metal sheet 1. ing. Each supply pipe 26, 28
Is connected to a flow path of a coating liquid storage tank (not shown).

Further, inside the coating booth 12, the coating processing section 14 is located on the near side in the transport direction of the metal sheet 1,
A temperature sensor 30 such as a radiation thermometer is provided so as to face the upper surface of the metal sheet 1, and a metal sheet heating unit 32 provided with an electric heater 34 is provided so as to face the lower surface of the metal sheet. Have been. The electric heater 34 of the sheet metal heating unit 32 is controlled by a controller (not shown) based on a detection signal from the temperature sensor 30. Then, the temperature of the metal sheet 1 is adjusted according to the measured temperature of the metal sheet 1, and the temperature of the metal sheet 1 before being sent to the coating processing unit 14 is controlled to be always constant. In the illustrated example, the temperature of the metal sheet 1 itself is measured by the temperature sensor 30, but the ambient temperature around the metal sheet 1 may be measured. Further, in the illustrated example, the temperature sensor 30 is disposed on the near side in the transport direction of the thin metal sheet 1 from the coating processing unit 14, but the temperature sensor is provided on the forward side in the transport direction of the thin metal sheet 1 from the coating processing unit 14. Alternatively, the temperature of the metal sheet 1 after the application liquid is applied may be measured. Further, the coating booth 12 is provided with a remote thermometer 36.
The ambient temperature inside the coating booth 12 is measured by 6 and the temperature inside the coating booth 12 is adjusted as needed.

In the coating apparatus having the above configuration, the temperature sensor 30
To measure the temperature of the metal sheet 1, and control the electric heater 34 of the metal sheet heating unit 32 according to the measurement result.
The temperature of the metal sheet 1 is kept constant. Therefore, even in winter or the like, the metal sheet 1 is supplied from the supply pipes 26 and 28.
The coating liquid supplied to the upper surface of the thin metal sheet 1 does not lose heat and the temperature of the coating liquid decreases, and the viscosity of the coating liquid does not increase. There is no need to worry about bubbles occurring in the coating liquid filled in the coating liquid.

[0020]

According to the method for applying a coating liquid according to the first aspect of the present invention, when the coating liquid is applied to the main surface of a thin metal plate having a plurality of fine concave portions formed therein, even in winter or the like,
Bubbles are not generated in the coating liquid filled in the concave portions, and therefore, it is possible to always form fine through holes having a desired shape by etching.

The use of the coating liquid coating apparatus according to the second aspect of the present invention enables the coating method according to the first aspect of the present invention to be suitably implemented, and a metal sheet having a plurality of fine concave portions formed thereon. When the coating liquid is applied to the main surface of the substrate, bubbles are not generated in the coating liquid filled in the concave portion even in winter or the like, so that fine holes having a desired shape are always formed by etching. It is possible to do.

In the coating apparatus according to the third aspect of the present invention, the metal sheet fed to the application position of the coating liquid is always kept at a predetermined temperature, so that the above-mentioned effect of the second aspect of the invention is reliably achieved.

[Brief description of the drawings]

FIG. 1 is a schematic front sectional view showing an example of a configuration of a coating liquid coating apparatus used for performing a coating liquid coating method according to the present invention.

FIG. 2 is a partially enlarged side sectional view for explaining a problem in a case where a coating liquid is applied to a metal thin plate by a conventional coating method and a fine concave portion of the metal thin plate is filled with the coating liquid.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 metal thin plate 10 coating liquid coating device 12 coating booth 14 coating processing unit 16, 18, 20 back-up roller 22, 24 squeegee roller 26, 28 coating liquid supply pipe 30 temperature sensor 32 metal thin plate heating unit 34 electric heater

Claims (3)

[Claims] 1. A method of applying a coating liquid to a metal sheet in which a coating liquid is applied to a main surface of a thin metal plate having a plurality of fine concave portions formed therein and the concave portion is filled with the coating liquid. A method for applying a coating liquid to a metal sheet, wherein the temperature of the metal sheet or the ambient temperature around the metal sheet is measured, and the temperature of the metal sheet is adjusted according to the measurement result. 2. A coating liquid supply means for supplying a coating liquid to a main surface of a metal sheet having a plurality of fine concave portions formed thereon, and a coating liquid supplied to the main surface of the metal sheet by the coating liquid supply means. Means for applying a coating liquid to the metal sheet, comprising: coating the metal sheet with a coating liquid filling means for filling the concave portion formed in the metal sheet by spreading the metal sheet on the metal sheet. Coating a coating liquid on a metal sheet, comprising: a temperature measuring means for measuring a surrounding atmosphere temperature; and a temperature adjusting means for adjusting a temperature of the metal sheet according to a measurement result by the temperature measuring means. apparatus. 3. The metal sheet is formed in a belt shape and is conveyed in the longitudinal direction thereof, and the temperature measuring means is provided on the near side in the conveying direction of the metal sheet with respect to the application liquid supply means and the application liquid filling means. For applying coating liquid to thin metal plates.