JPS6226737A - Manufacture of fluorescent character display tube - Google Patents

Abstract

PURPOSE:To simplify the manufacturing process by arranging a control electrode on control electrode substrate to form a control electrode assembly then adhering to an anode substrate arranged with anode electrode and forming anode pattern. CONSTITUTION:Anode electrode 2 is arranged on the anode substrate 1 then an adhesive layer 3 is provided except an anode pattern exposing section 2b. While a control electrode 5 and a protection layer 6 are provided on a control electrode board 4 having an anode pattern window section 4a. Then they are laminated and adhered and sticked with fluorescent material past through the window section 4a to form an anode pattern 7. Thereafter, the protection layer 6 is removed to expose the control electrode 5 and assembled together with a hot-cathode 8 into a face member 9 thus to form a fluorescent character display tube. When executing the control electrode forming process independently, the manufacturing process is simplified while the accuracy is improved.

Description

[Detailed description of the invention] (Technical field) The present invention relates to a method for manufacturing a fluorescent display tube.

(Prior Art) In a fluorescent display tube, an anode pattern consisting of a fluorescent screen is formed on a large number of anode electrodes arranged in one or more rows in one direction, and this is sealed in a vacuum container together with a hot cathode. , while generating thermionic electrons from the hot cathode, selectively applying a positive voltage to the anode electrode according to the information to be displayed, the thermionic electrons are attracted to the selected anode electrode, and the thermionic electrons become fluorescent. Information is displayed by the fluorescence emitted when it collides with a surface, and it is already well known as a barcode display tube and a phosphor dot array tube.

First, referring to FIG. 5, an outline of a fluorescent display tube will be explained using a fluorescent dot array tube as an example.

In FIG. 5, reference numeral 20 indicates an anode substrate made of glass, ceramic, resin, or the like. Anode substrate 20
A series of anode electrodes 21 are arranged in a row in the longitudinal direction of the substrate, and an anode pattern 22 made of a fluorescent screen is formed on each of the anode electrodes 21. The size of each phosphor screen is 40 x 40 μM to 50 x 5
Although the phosphor screen is extremely small, such as a 0μ hole, the size of the phosphor screen is shown larger than the other members in the figure.

On both sides of the anode pattern arrangement of the anode substrate 20, thick film insulating layers 23.23 are formed along the longitudinal direction of the substrate, and control electrodes 24.24 are formed on these, respectively. In FIG. 5, reference numeral 25 indicates a tungsten wire as a hot cathode stretched in the longitudinal direction of the substrate, the surface of which is coated with an electron emissive substance such as Ba5rO. Further, reference numeral 26 denotes a face member made of a transparent material such as glass, and as shown in FIG. 6, it is integrated with the anode substrate side. Thus, the anode substrate 20, the thick film insulating layers 23, 23, the control electrodes 24, 24 . The face member 26 forms a closed space, and within this space,
Anode electrode 21, anode pattern 22, hot cathode 25.25
is locked up. The closed space is highly evacuated.

When a suitable voltage is applied to the control electrodes 24, 24 and an alternating current of several tens of milliamps is passed through the hot cathode 25.25, the hot cathode 25.25 is heated by Joule heat and emits thermoelectrons. In such a state, if a positive voltage is applied to one of the anode electrodes 21 to make it a positive potential,
The thermoelectrons are attracted to the electrode portion of the anode electrode 21 having a positive potential, and when sucked into the electrode portion, the anode pattern 22
excites the energy state of the fluorescent substance. The excited fluorescent substance emits fluorescence when returning to the ground state. This fluorescence is detected through the face member 26.

Such a phosphor dot array tube is used as a part of the optical system of an optical printer or as a bar code display tube.

Conventionally, such a fluorescent display tube has an anode electrode 21 formed of a strip-shaped electrode by photo-etching on an anode substrate 20.
A thick film insulating layer 23 made of thick film insulating glass is formed on the surface of the substrate including the electrode by exposing a part of the electrode 21 by a screen printing method, and then fired. Next, only a portion of the exposed electrode is exposed, and the surface of the substrate including the electrode is covered with a photoresist layer. Then, in the phosphor screen forming step, the substrate is immersed in a dispersion liquid in which phosphor particles are dispersed, facing the counter electrode at a predetermined distance, and a voltage is applied between the anode electrode and the counter electrode. . The phosphor particles in the dispersion are moved toward the anode electrode by the electric field formed between the two electrodes.
It adheres to the exposed electrode portion to form an anode pattern. The control electrode 24 is formed by an appropriate method such as photoetching after the phosphor screen is formed. Then, the anode substrate 20 on which each electrode and anode pattern are formed is integrated with the face member 26.

By the way, in the manufacturing method described above, the anode substrate 2
0 is the anode electrode 21. Thick film insulation layer 23. Control electrode 24
must go through all of the forming steps.

In other words, there is a problem that the manufacturing process of the fluorescent display tube becomes long. In addition, with the electrodeposition method, it is difficult to set the electrodeposition conditions, and the shape and thickness of the phosphor screen vary.

There are problems in that the phosphor screen dots protrude and the connections between the dots form a uniform anode pattern, resulting in a lid.

(Objective) An object of the present invention is to provide a method for manufacturing a fluorescent display tube that simplifies the manufacturing process and can form a stable anode pattern.

(Structure) The present invention comprises a control electrode assembly in which a control electrode is formed on a control electrode substrate, this control electrode is further covered with a protective layer, and window holes are formed to match the arrangement pitch of the anode electrodes. This assembly is polymerized and adhered to an anode substrate on which anode electrodes are arranged in rows, and phosphor particles are supplied to the anode electrodes through the window holes to form an anode pattern. It is characterized by removing.

The present invention will be explained in detail below.

FIG. 1 shows the steps of the present invention, including a positive electrode forming step in which at least one row of anode electrodes made of a conductive material is provided on an anode substrate, and a control electrode forming step in which a control electrode is formed on the control electrode substrate. A control electrode forming step and a protective layer forming step of covering the control electrode with a protective layer are performed independently,
After forming an adhesive layer on the anode substrate, the two substrates are bonded together in an adhesion process, an anode pattern (phosphor screen) is formed in an anode pattern formation process, and the protective layer is removed. It is now ready for the final assembly process.

Each step will be explained in detail below.

Anode electrode forming process: As shown in FIG. 2 (2), an anode electrode made of aluminum is photoetched onto one surface of the anode substrate 1 made of, for example, a glass plate, as shown in FIG. 2 (1). Formed by law. This anode electrode 2 has a width of approximately 50 μm.
They are strip-shaped and are formed in a line in the longitudinal direction of the substrate with an interval of about 35 μm between adjacent electrodes, and the lead portions 2a of each electrode are drawn out to the left and right side edges of the substrate at every other electrode (see Fig. 3). reference).

Adhesive Layer Forming Step As shown in FIG. 2 (3), adhesive layers 3 made of hot melt glass are formed on both sides of the anode substrate 1 including the anode electrodes 2 along the direction in which the electrodes 2 are arranged. At this time, the central part of the anode electrode 2 is exposed as an exposed part 2b.

Control electrode forming step As shown in FIG. 2(a), an insulator made of, for example, lead glass is formed with anode pattern window holes 4a having the same arrangement pitch as that of the anode electrodes 2 (see FIG. 3). The control electrode substrate 4 shown in FIG.
As shown in b), a mesh-like control electrode 5 is formed. This control electrode 5 is also formed with window holes 5a having the same pitch and size as the anode pattern window holes 4a.

As shown in FIG. 2(C), a protective layer 6 is formed on the control electrode 5 to cover its surface. Thereby, the control electrode assembly A is constructed. The protective layer 6 is, for example, a photoresist layer, and has window holes 6a having the same pitch and size as the window holes 4a and 5a. 7B holes 4a, 5a for anode putter 'J.

6a regulates the size and arrangement pitch of the anode pattern, which will be described later.

Bonding Step This step is a step of bonding the anode substrate 1 on which the adhesive layer 3 is formed and the control electrode assembly A to form the substrate assembly B.

As shown in FIG. 2 (4), the adhesive layer 3 of the anode substrate 1,
The control electrode assembly A is placed on top of the control electrode assembly A, and is fired in a firing furnace to melt the adhesive layer and bond them together. At this time, the control electrode assembly A and the anode substrate 1 have window holes 4a and 5a as shown in FIG.

6a and the exposed portion 2b of the anode electrode 2 are exposed, for example, by a positioning means consisting of a combination of a positioning pin a and a positioning hole, the positions of the anode electrode 2 and the anode electrode 2 are determined, and then they are bonded to each other.

Anode pattern forming step In this step, window holes 6a, 5a, 4a are formed in the exposed portion 2b of the constructed substrate assembly B, as shown in FIG.
A phosphor paste containing phosphor particles is deposited through the wafer to form an anode pattern 7 as shown in FIG. 2(5). The phosphor paste is made by dispersing zinc oxide phosphor (Zn○: Zn) in a solvent consisting of, for example, isopropyl alcohol ((CH3L CHOH)), and adding aluminum nitrate (A1(N O3) a.9H20) as a control agent.
It is made into a paste by dissolving it.

The phosphor paste is moved in the longitudinal direction of the substrate by a nozzle or application roller (not shown) in the substrate assembly B.
supplied to the window hole. The phosphor paste supplied to the recesses having the window holes 4a, 5a, and 6a as peripheral walls and the exposed portion 2b as the bottom is squeezed by a squeezing member such as a brush (not shown) to make the thickness uniform. Thereafter, when the phosphor paste is dried and the liquid component is blown off, the remaining phosphor particles form an anode pattern 6 as shown in FIG. 2 (5).

Protective layer removal process From the substrate assembly B on which the anode pattern 7 is formed as shown in FIG. 2(5), the protective layer 6 is removed as shown in FIG. 2(6).
remove. As a result, the control electrode 5 is exposed, as also shown in FIG. By removing the protective layer 5, the phosphor particles adhering to the surface of the protective layer are removed, and adjacent anode patterns (dots) are no longer connected by the phosphor particles.

Assembling process The substrate assembly B on which the anode pattern 7 shown in FIG. This means that the fluorescent display tube 10 has been manufactured by assembling the face member 9 integrally with the face member 9. At this time, the closed space 11 is highly evacuated.

(Effects) As described above, the process of forming the control electrode covered with the protective layer is performed independently from the series of steps, the control electrode substrate is adhered to the anode substrate, and the control electrode is formed through the anode pattern window hole. According to the present invention, in which the protective layer is removed after the anode pattern is formed by supplying the phosphor paste using can be formed with. Since the protective layer is removed after the phosphor paste is supplied, there is no protrusion of the phosphor or connections between dots.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing the steps of the method for manufacturing a fluorescent display tube according to the present invention, FIG. 2 is a process diagram showing a specific example of the same as a cross-sectional view, and FIG. 3 is a process diagram showing a control electrode assembly and an anode substrate. FIG. 4 is a plan view partially showing the substrate assembly after the protective film has been removed, and FIG. 5 is an exploded perspective view showing a phosphor dot array tube as an example of a fluorescent display tube. , 6th
The figure is a sectional view of the same as above. DESCRIPTION OF SYMBOLS 1... Substrate for anode, 2... Electrode for anode, 3... Adhesive layer, 4... Substrate for control electrode, 5... Control electrode, 6
...Protective film, 4a, 5a, 6a... Window hole for anode pattern. 7...Anode pattern, 9...Face member, lO・
... Fluorescent display tube, A... Control electrode assembly, B... Substrate assembly. Shuu 5 Illustration 6

Claims (1)

[Scope of Claim] A fluorescent display tube having an anode electrode provided on an anode substrate, an anode pattern formed on the anode pattern consisting of a fluorescent screen, and a control electrode insulated from the anode electrode, comprising: In the electrode formation step, anode electrodes made of conductive material are arranged in rows at a predetermined pitch on the anode substrate, and in the adhesive layer formation step, anode electrodes made of conductive material are arranged on the anode substrate surface along the electrode arrangement direction. A part of the anode electrode is exposed to form an adhesive layer, and a dot-shaped anode pattern window hole is formed in the control electrode forming step at the same arrangement pitch as the anode electrode. A control electrode made of a conductive material having window holes arranged at the same pitch as the window holes for the anode pattern is provided on an insulating control electrode substrate, and a surface other than the window holes is placed on the control electrode. a control electrode assembly is formed by forming a protective layer covering the anode, and polymerizing the control electrode assembly on the anode substrate with the exposed portion of the anode electrode corresponding to the anode pattern window hole. These are glued together and in the anode pattern forming process,
supplying a phosphor paste containing phosphor particles to the exposed portion of the anode electrode through the window hole of the control electrode assembly;
A method for manufacturing a fluorescent display tube, comprising: attaching phosphor particles to the anode electrode to form an anode pattern; and removing the protective layer to expose the control electrode in a protective layer removal step.