JPS61198531A - Manufacture of substrate for anode of fluorescent character display tube - Google Patents

Abstract

PURPOSE:To provide fluorescent pieces at small intervals or a high density, by making an inflammable film which has such a thickness as to enable the removal of the film by baking and is located except where the fluorescent pieces are to be provided, and by electrodepositing the fluorescent pieces, and removing the inflammable film by baking, thus avoiding letting the fluorescent pieces cling to the side walls of anodes. CONSTITUTION:Anodes 2 are made of a thin aluminum film of about 1.5mum in thickness on a glass plate 1. A liquid made of polyvinyl alcohol in the main and containing a diazo group as a photosensitive group is applied to the whole surface of the side of the glass plate 1 by spin-coating so that the thickness of the applied liquid thereon is about 20mum. The applied liquid is dried. The dried film is exposed to light partially blocked by the pattern of the anodes 2 as a mask, so that an inflammable organic substance film 3 is provided. A fluorescent substance 4 is electrodeposited at a thickness of about 15mum on the anodes 2. Baking is then performed at about 500 deg.C so that the inflammable organic substance film 3 is burnt away. Desired fluorescent pieces 4 are thus provided on the anodes 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a fluorescent display tube anode substrate for high-density formation of phosphors.

[Conventional technology]

There are two methods for forming phosphors in fluorescent display tubes: electrodeposition and printing. Since the printing method is not suitable, the electrodeposition method is adopted.

[Problem that the invention seeks to solve]

However, due to the power, the phosphor is the anode number 1! When it adheres to the electrode, it adheres not only to the surface of the anode but also to the wall of the anode, so
When the distance between the anode electrodes is about 30 μm, the adjacent y'c
Since the phosphor attached to the side wall of the III electrode came into contact with the side wall, there was a limit to the high density formation of the phosphor.

Therefore, an object of the present invention is to provide a method for manufacturing a fluorescent display tube anode substrate, which can form a phosphor layer at a higher density than the conventional method when forming a phosphor layer by electrodeposition. I'm going to do it.

[Means for solving problems]

In order to achieve these objects, the present invention forms a flammable film with a thickness that can be removed by firing on parts other than the part where the phosphor is formed, and removes it by firing the flammable film after forming the phosphor. This is how it was done.

[Action 2 I The phosphor forms a flammable film that remains on the burnt area.

[Smiley example] The figure is a process diagram showing an example of this invention.

First, as shown in (a) K, a film with a thickness of 1 is deposited on a glass substrate 1.
．． An anode electrode 2 with a thickness of approximately 5 μm is formed of an aluminum thin film. For example, the anode electrode 2 has a size of about 50 μm×50 μm, and the distance between the anode electrodes is about 30 μm. It also has 12.5 fine, high-density coatings of 1mm2.

Next, as shown in (b), a photosensitive combustible organic material film 3 is formed on a portion other than the portion where the phosphor is to be electrodeposited. For this reason, K is, for example, about 20
It is applied to the entire surface of the glass substrate 1 in a thickness of μm using a spin code method, and is made to tremble.

(The film thickness becomes about 12 μm when dried.) By exposing the film to light using a positive pattern mask, a combustible organic substance film 3 can be formed in a region other than the region where the C1 phosphor is to be formed. At this time, by controlling the exposure to be excessive, the light rays are prevented from wrapping around, and the electrode is made slightly smaller than the partial vinyl anode electrode 2 from which three pieces of combustible organic matter are to be removed. As a result, the exposed portions are hardened. Next, complete development is performed to remove portions of the combustible film that have not been exposed to light (uncured portions).

Thereafter, as shown in (C), the phosphor 4r is layered on the anode electrode 2 by electrodeposition. This is the whole board sound ZnO: Z
n) A phosphor having a film thickness of about 5 μm is formed by immersing the phosphor in an electrodeposition solution in which the phosphor is suspended and performing electrodeposition under predetermined conditions.

Next, by performing baking at around 500°C, the combustible organic substance film 3 is burnt off and removed, as shown in (d).
A target phosphor 4 is formed on the anodic electrode 2. Since the area of this phosphor 4 is smaller than that of the anode electrode 2, the electrons on the glass substrate do not affect the light emitting state of the phosphor 4, so there is no chipping of the light emitting part, and the adjacent phosphor Contact of light bodies often occurs. Therefore, the space between the phosphors can be improved and the phosphors can be formed at a high density.

When we made a prototype and measured the phosphor sound, we found that it was 45 to 48 μm square and 15 μm thick. In addition, in order to investigate the effect of the flammable organic material film used on the phosphor, the luminescent properties of the phosphor were adjusted, or it was found to be comparable to that formed by conventional electrodeposition.

The film thickness of the combustible organic substance film ij:mk As a result of conducting experiments,
It has been found that 5 to 30 μm is a suitable value for the following reasons.

(a) If the film thickness is less than 5 μm, the phosphor will adhere to the side wall of the anode electrode and no effect will be obtained.

(b) If it is thicker than 30 μm, the combustible organic substance film cannot be processed accurately.

(c) The phosphor layer can be constructed with the highest accuracy when the flammable organic substance film and the phosphor film thickness are approximately the same, and from the viewpoint of luminous efficiency, the phosphor film thickness may be approximately 5 to 30 μm.

〔Effect of the invention〕

As explained above, the present invention involves forming a combustible film having a thickness that can be removed by firing on parts other than the part where the phosphor will be formed, and then depositing the phosphor on the entire part by electrodeposition.
Since the flammable film is then completely removed by firing, the phosphor does not adhere to the side wall of the anode, which has the effect of allowing all adjacent phosphors to be formed in close proximity to each other at high density.

[Brief Description of the Drawings] The figures are -'j! of this invention. The process diagram is shown in the example meeting. 1...Glass substrate, 2...Anode electrode, 3...
・Flammable organic substance film, 4...fluorescent material.

Claims (1)

[Claims] In a method for manufacturing a fluorescent display tube anode substrate comprising a substrate having a thin film anode and a phosphor layer electrodeposited on the anode portion of the substrate, forming a thin film anode electrode on the substrate. Step: Applying a photosensitive combustible film that can be removed by baking to a thickness of 5 to 30 μm on the anode substrate. Using the anode pattern as a mask, the area of the part where the phosphor will be formed is smaller than the area of the anode. A step of over-exposing the flammable film to 100%, a step of removing the unexposed portion of the flammable film by development, a step of electrodepositing a phosphor layer, and a step of removing the flammable film by baking. 1. A method for manufacturing a fluorescent display tube anode substrate, comprising forming an anode substrate by sequentially performing the steps.