JPS6313293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a fluorescent display tube, particularly a dot matrix fluorescent display tube.

A fluorescent display tube consists of a filament that emits electrons and a plurality of electrodes whose surfaces are coated with phosphor. Any one of these electrodes can be selected to receive the electrons from the filament. Then, the phosphor on the surface of the electrode emits light to display a desired pattern or character. Among such fluorescent display tubes, dot matrix fluorescent display tubes have unit light-emitting parts formed by dots arranged and distributed in a grid pattern, and the combination of these light-emitting dots can freely display alphanumeric characters and kana characters. This is a convenient fluorescent display tube.

This kind of dot matrix fluorescent display tube is
Conventionally, it was made as follows. That is,
A wiring layer is formed using a conductive material such as silver by printing technology on the surface of an insulating substrate such as glass or ceramic, and after this is fired, a dot matrix phosphor of this wiring layer is applied. An insulating layer made of glass is printed on the surface of the substrate, leaving the remaining portion, and then baked. That is, an insulating layer having through holes for forming a dot matrix is formed in a part of the wiring layer. Furthermore, carbon and phosphor are formed by printing technology in a state where they are connected to a part of the wiring layer through this through hole, and then dried. Thereafter, a thin wire serving as a filament is stretched above the phosphor pattern, a glass container is sealed on the top surface of the insulating substrate, and the inside of the container is placed in a vacuum state.

However, in the manufacturing method of fluorescent display tubes that makes full use of the above-mentioned printing technology, there is a limit to increasing the dot density and wiring density of the dot matrix, and it has been difficult to obtain high-quality images or characters. .

Therefore, the present invention overcomes these disadvantages and provides a dot matrix display fluorescent display tube with high dot density and wiring density, which can provide high-quality images or characters.

In order to achieve such an object, the basic manufacturing method of the present invention includes a step of forming a wiring pattern on an insulating substrate by vapor deposition using a mask, and a step of forming a photoresist only on the wiring pattern. , forming an insulating layer in common on the photoresist and the exposed surface of the insulating substrate, and removing the photoresist and the insulating layer on the photoresist while leaving the insulating layer on the surface of the insulating substrate. and a step of electrodepositing a phosphor on the wiring pattern. For example, a wiring pattern is formed by vapor depositing aluminum and then nickel using a mask with a desired pattern on an insulating substrate, and then a photo is placed on the dots on the aluminum/nickel wiring pattern. A resist film with a dot matrix pattern is formed using resist technology, and a black insulating layer, such as a TiO layer, is formed by vapor deposition using this resist film.

Next, the present invention will be explained in detail with reference to the drawings. The figure is a cross-sectional process diagram for explaining the method of the present invention,
First, in Fig. a, aluminum and then nickel are deposited on an insulating substrate 1 made of, for example, glass through a slit-shaped mask to form an aluminum/nickel wiring pattern 2. Next, a photoresist film 3 is applied at the stage shown in FIG. b, and further, as shown in FIG. Next, as shown in figure d, a black TiO insulating layer 4 is deposited over the entire surface, and as shown in figure e, the resist film 3' is deposited on the dot portions on the aluminum/nickel wiring pattern 2.
When the TiO layer 4 on the resist film 3' is removed, the TiO layer 4 on the resist film 3' is also removed. Finally, carbon 5 and then phosphor 6 are electrodeposited on the exposed aluminum/nickel pattern as shown in figure f. After that, a grid electrode and a filament are installed above the phosphor 6 (not shown), the glass container is sealed, and the inside of the glass container is brought into a vacuum state to complete the process. Note that the wiring layer 2 and terminal portions of the filament and grit electrodes (not shown) are drawn out of the glass container.

In the above, wiring layer 2 was formed by vapor-depositing nickel after aluminum, because if nickel was vapor-deposited directly on the glass substrate, the adhesion force would be small, so aluminum was used as the base to increase the adhesion force. -ing Further, if aluminum alone is used, oxidation occurs when the glass container is sealed, increasing the resistance of the wiring, and because ordinary solder cannot be used to solder the leads, nickel is additionally coated.

The dot matrix display fluorescent display tube manufactured in this way has a highly dense dot and wiring pattern, and also has a back plate.
Because of the black color of the TiO layer, clear character display could be obtained. In addition, other benefits include:
Since the wiring is made of aluminum/nickel, short circuits between terminals due to migration under high temperature and high humidity conditions, which is a problem with conventional silver printed wiring, are unlikely to occur.

As mentioned above, the dot matrix fluorescent display tube manufactured by the method of the present invention has a high dot density, so it is possible to display high-quality characters, and the conductive material between the terminals is not affected by the applied voltage under high temperature and high humidity. It has superior reliability because migration does not occur.

[Brief explanation of the drawing]

Figures a to f are cross-sectional views for explaining the manufacturing process according to the present invention. 1... Glass substrate, 2... Wiring layer, 3, 3'...
...Photoresist layer, 4...TiO insulating layer, 5...
Carbon electrodeposition layer, 6...phosphor layer.

Claims (1)

[Claims] 1. A step of forming a wiring pattern on an insulating substrate by vapor deposition using a mask, a step of forming a photoresist only on the wiring pattern, and a step of forming an insulating layer on the photoresist and the exposed surface of the insulating substrate. a step of removing the photoresist and the insulating layer on the photoresist while leaving an insulating layer on the surface of the insulating substrate; and a step of electrodepositing a phosphor on the wiring pattern. A method for manufacturing a fluorescent display tube, comprising: