JPS58189943A - Forming method of coated layer with pulverulent body - Google Patents

Abstract

PURPOSE:To form a coated layer with pulverulent body at a part where tackiness is produced by light of a sensitive paint film in a short time, by setting up a potential difference between a base body coated with a film carrying tackiness or an ordinary film and an electrode opposed to the base body, while having the pulverulent body and the film contacted with each other after giving a charge to the pulverulent body from the electrode. CONSTITUTION:A luminous tacky sensitive material 2 is applied to a glass panel 1, and a strapy figure is exposed through a shadow mask. Next, a blue luminescent zinc sulfide phosphor 3, etc., stuck with a cobalt blue pigment and the like is given from a powder feed nozzle 4 adjacent to the lower part of the panel. Furthermore, a wire net 5 is set up in an interspace between a luminous tacky film and the powder feed nozzle 4 and then a voltage of -10kV, for example, is impressed on the luminous tacky film grounded. With this, a coated layer with pulverulent body can be formed up at a part where tackiness is produced by light of the sensitive paint film in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming a powder coating layer. In particular, it relates to a method of forming a powder coating layer suitable for forming a fluorescent surface of a color cathode ray tube.

Traditionally, the manufacturing process for the phosphor surfaces of color cathode ray tubes is extremely complex and requires a large amount of water, as it requires multiple wet coatings of phosphor slurry, exposure, rinsing, and drying. And so. In order to improve these problems of the prior art, some of the products of the present invention are formulated with photo-adhesives that become sticky when irradiated with light, such as substances such as aromatic diazonium salts, or A thin layer of a composition containing a water-soluble polymer and the like is formed on the surface of the substrate, and then exposed to light using a shadow mask.
He proposed a method of forming a phosphor pattern by imparting adhesiveness to the patterned portion of a desired phosphor, and coating and adhering desired phosphor particles thereto (Japanese Patent Laid-Open No. 53-126861). However, in this method,
It became clear that it took a long time to bring the powder into contact. It is not desirable that even one process takes a long time from the economic point of view of manufacturing color cathode ray tubes.

An object of the present invention is to form a powder coating layer in a short time on a portion of a photosensitive coating film that has become sticky due to light.

In the powder application method described above, the requirements for shortening the application time are to increase the chance of contact between the powder and the thin layer of the part that has become sticky due to light, and to increase the chance of contact between the powder and the thin layer of the part that has become sticky due to light. The body is effectively fixed in thin no.

The method for forming a powder coating layer of the present invention involves creating a potential difference between a substrate coated with an adhesive film or coating and an electrode facing the substrate, applying an electric charge to the powder from the electrode, and applying an electric charge to the powder. The method is characterized by bringing the powder into contact with the membrane. According to this method, the powder charged by the electrode moves along the lines of electric force, efficiently comes into contact with the thin film, and is fixed.

Examples of methods of imparting electric charge to the powder include a method of passing the powder between mesh-like electrodes, a method of blowing the powder out of a nozzle, and using the nozzle itself as a counter electrode, as exemplified in the examples described later. There are various methods. Another method is to charge the powder by passing it through a corona discharge space.

One side that provides a potential difference is a photosensitive thin film or a substrate coated with it. In general, it is preferable to apply a force that creates a potential difference between the photosensitive thin film and the electric mail because the adhesion efficiency of the powder to the thin film is higher than that of creating a potential difference between the substrate and the electrode. However, there are problems such as easy discharge and the need for special measures to electrically connect the photosensitive thin film to the outside. That is, when applying a phosphor in the form of a stripe, the upper and/or lower ends of the stripe portion may be connected in a band shape with a transparent conductive film or a finely powdered graphite film, and one end of the strip may be electrically connected to the outside. . The exposed photoresist film has electrical conductivity. Alternatively, the entire inner surface of the face plate may be made of a transparent conductive film.

The present invention will be explained below using examples.

Example 1 As shown in FIG.
861) and expose a striped pattern through a shadow mask.

Next, a blue-emitting zinc sulfide phosphor 3 coated with cobalt blue pigment is applied from a powder application nozzle 4 close to the bottom of the panel. A wire mesh 5 is installed between the photoadhesive film and the special nozzle for applying powder, and -IQKV is applied to the grounded photoadhesive film. The phosphor sprayed with air from the powder application nozzle comes into contact with the wire mesh and receives a negative charge.
It floats along the lines of electric force from the wire mesh toward the photoadhesive film and is fixed in contact with the photoadhesive film. When applying powder, the developing nozzle 6
Injecting air from the screen prevents the mesh from clogging,
Uniform powder application can be achieved by stirring the suspended powder. When the film was applied for 20 seconds using 35mm stainless steel as a wire mesh, the adhesive imitation fluorescent film after incubation had a sufficient film thickness of 2.0 mg 7 cm 2 . In addition, when no voltage is applied to the wire mesh, 1 m g /
Only a thin fluorescent film with a thickness of less than cm" was obtained.

A similar operation was repeated for a green-emitting zinc sulfide phosphor and a red-emitting europium-activated yttrium oxysulfide phosphor with an iron oxide red pigment attached to form a color cathode ray tube fluorescent surface.

Example 2 Next, another embodiment of the present invention will be described with reference to FIG.

Ground the nine poles 7, and connect the color cathode ray tube glass panel 1.
Let it adhere to. A photoadhesive photosensitive material 2 is applied to the inner surface of the panel, and a striped pattern is exposed through a shadow mask.

An electrode 8 to which high voltage is applied is installed facing the panel.

The high voltage electrode is attached to the developing nozzle 6 and the powder application nozzle 4, and moves as the nozzles move.

In this way, the phosphor 3 sprayed from the powder application nozzle moves along the /l electric lines of force generated between the high voltage electrode and the photosensitive material that has been exposed to light and has become sticky. and is applied efficiently. By sequentially performing this operation on a blue-emitting zinc sulfide phosphor to which a cobalt blue pigment is attached, a green-emitting zinc sulfide phosphor to which an iron oxide red pigment is attached, and a red-emitting europium-activated yttrium oxysulfide phosphor to which an iron oxide red pigment is attached. , we were able to form a color cathode ray tube fluorescent surface.

Embodiment 3 Next, another embodiment of the present invention will be described with reference to FIG. A photoadhesive photosensitive material 2 is applied to a glass panel 1 for a color cathode ray tube to which a grounded electrode 7 is attached, and exposed to light through a shadow mask.

A high voltage electrode plate 8 is installed facing the panel. The phosphor placed on the electrode plate flies along the lines of electric force towards the exposed photo-adhesive photosensitive material and adheres thereto. This electrostatic flying phenomenon is promoted by vibrating the electrode plate or by switching the polarity of the high voltage. In order to form an even fluorescent film over the entire panel, it is effective to install a device with a stirring function within the device. for example,
For example, a nozzle that spouts gas while rotating, such as a rotary fountain jet nozzle, is installed in the device.

In this way, a phosphor film corresponding to the exposed pattern is formed, but due to a separate phenomenon, the phosphor that has adhered to the unexposed area and the phosphor that has weakly adhered to the exposed area are removed, resulting in a high quality film. A fluorescent film can be obtained. Perform operations like this with red, blue,
By sequentially performing the steps for each green phosphor, a phosphor film for a color cathode ray tube could be formed.

As explained above, the gist of the present invention is to create a potential difference between a photosensitive film or a substrate coated with a photosensitive film and an electrode facing the same in a method for forming a patterned powder coated layer using a photo-adhesive photosensitive film. The purpose is to provide the powder and bring the powder into contact with the photoresist film via the electrode. FIG. 1 shows an example in which one side on which a potential difference is provided is a photoresist film, and FIGS. 2 and 3 show examples in which one side is a substrate. These embodiments show examples of combinations with the voltage application method; however, in FIG. 1, a potential difference may be provided between the substrate and the electrode;
In the figure, a potential difference may be provided between the photoresist film and the electrode. Generally, it is better to create a potential difference between the photoresist film and the electrode.
The adhesion efficiency of the powder to the photoresist film is higher than creating a potential difference between the substrate and the electrode, but on the other hand, it is more likely to cause electrical discharge, and special treatment such as prewatering is required to electrically connect the photoresist film to the outside. There are disadvantages such as requiring

Examples of the counter electrode are a metal plate in FIG. 1, a metal plate attached to the nozzle in FIG. 2, and a vibrating metal plate installed at the bottom of the apparatus box in FIG. 3. In each embodiment, the voltage applying side and the grounding side may be reversed.

The potential difference used varies depending on the withstand voltage of the system.
When the distance between the mesh and the photoresist film is 5 mm, the voltage is about 1 QkV, but in the case shown in Figures 2 and 3, when the distance between the electrode and the nearest ground potential is 15 cm or more, the voltage is 60 kV. It is effective to take some measures.

In order to exhibit the features of the present invention, it is effective to charge the powder. How to give charge.

In addition to providing energy from electrodes, there is a method that uses corona discharge. For example, in FIG. 1, when needle-like protrusions are placed on a mesh-like electrode, a corona discharge is generated from the protrusions, and a particularly good fluorescent film is formed in that area. Other methods include passing through a corona discharge space when transporting the fluorescent material.

As described above, the present technology provides a method for forming a graphic powder coating layer with extremely high independence.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, and FIG. 3 are diagrams showing one embodiment of the present invention. 1...Glass panel, 2...Photosensitive material, 3...Fluorescence L 4...Nozzle, 5
... wire mesh, 6 ... nozzle, 7 ...
...electrode, 8...electrode. Chrysanthemum 2 Figure 3

Claims (1)

[Claims] 1. In a method for forming a patterned powder coated layer using a photo-adhesive photosensitive film, a potential difference is created between the photosensitive film or a substrate coated with the photosensitive film and an electrode facing the same. . A method for forming a patterned powder coating layer, which comprises bringing the powder into contact with a photoresist film through an electrode. 2. The method for forming a powder coating layer according to claim 1, wherein the electrode is a metal mesh electrode. 3. The method for forming a powder coating layer according to claim 1, wherein the electrode is a nozzle for blowing out powder. 4. The method for forming a powder coating layer according to claim 1, wherein the electrode is plate-shaped and the powder is disposed on the electrode.