JPH10340703A - Mercury emitting structure suitable for use in fluorescent discharge tube, method for manufacturing the same, and fluorescent discharge tube using mercury emitting structure - Google Patents

Abstract

(57) Abstract: The present invention relates to a mercury-releasing structure capable of being inserted into a glass bulb without releasing dimensions and releasing mercury into the bulb, a method for manufacturing the same, and a fluorescent discharge tube using the same. The purpose is to provide. SOLUTION: A mercury emitting structure used for a fluorescent discharge tube in which a pair of electrode mounts are sealed at both ends of a glass bulb 13, wherein the mercury emitting structure 1 is one or more kinds of metals such as nickel, titanium, tantalum and the like. The sintered metal and the mercury, which are made by hardening powder into a size that can be inserted into the glass bulb 13, are configured by heat treatment. After being inserted into the glass bulb, the mercury evaporates and is released into the bulb 13 by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp in which mercury is sealed in a glass bulb, and more particularly to a mercury emitting structure for sealing mercury, a method of manufacturing the same, and a fluorescent lamp using the mercury emitting structure. About.

[0002]

2. Description of the Related Art In recent years, cold cathode and hot cathode fluorescent discharge tubes have been frequently used as backlights for OA equipment, liquid crystal televisions, and the like. Mercury is enclosed in addition to the rare gas such as. Since the handling of mercury involves danger, careful attention must be paid to enclosing it in a tube. Recently, mercury-releasing structures have been increasingly used instead of directly enclosing raw mercury. As the mercury releasing structure, a structure in which a metal compound of one of titanium or zirconium metal and mercury is formed on a rod-shaped or plate-shaped nickel metal substrate, which is sealed at an open end of a glass tube. A mercury-releasing structure is attached to the electrode part in the tube of the electrode mount and its vicinity, and the mercury-releasing structure is heated with a high-frequency coil from outside the glass tube to evaporate and release mercury combined with the metal on the nickel metal substrate. The method of diffusion and encapsulation is used.

In this mercury releasing structure, first, mercury is sealed in a glass tube in the form of a solid metal compound, and then the mercury is evaporated and released by heating from outside the glass tube. Since some titanium and zirconium can be used as getter materials to absorb impurities in the pipe, the handling of mercury is compared to using a conventional mercury dozer to mechanically seal liquid mercury through the exhaust pipe. It is excellent in terms of safety and control of the amount of enclosed mercury.

[0004]

However, in the above mercury releasing structure, when the heating temperature from outside the glass tube is low, the speed at which mercury is released is slow. For example, the structure is heated to 900 ° C. in a vacuum of 10 ⁻⁴ mmHg. Of mercury content of the mercury emitting structure
It takes several minutes to several tens of minutes to release 0%. In this case, a sufficient amount of mercury cannot be released and sealed in a manufacturing process that requires high-speed operation in mass production as at present.

[0005] As a metal substrate of the mercury release structure,
In the case of using nickel-plated iron base,
High-frequency heating causes nickel to evaporate and adhere to the inner wall of the glass tube, resulting in a reduction in luminous flux.

Although a nickel cylinder filled with a metal compound of mercury and titanium or zirconium has been proposed, the nickel cylinder may be cracked or sometimes destroyed by high-frequency heating. doing.

Further, in the case of the above plate-shaped or rod-shaped mercury-releasing structure, when the tube diameter of the fluorescent discharge tube is made extremely small, it is necessary to process a metal substrate to a shape suitable for the tube diameter. In addition, the number of processes for this purpose cannot be denied, and at the time of size cutting, the mercury metal compound falls off from the metal base, so that a predetermined amount of mercury cannot be enclosed, and furthermore, there is a problem that it may lead to environmental pollution. In order to address this problem, in addition to consideration of workability in processing, a processing method is required to prevent mercury and metal compounds from falling off the metal substrate, and adjustment of the mercury content of the mercury-releasing structure is required. , Complicated and troublesome work such as management.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a mercury emitting structure suitable for use in a fluorescent discharge tube, a method for manufacturing the same, and a fluorescent discharge tube using the same. Aim.

[0009]

In order to achieve the above object, a mercury emitting structure adapted for use in the fluorescent tube of the present invention is compacted and sintered to a size that can be inserted into a glass bulb of the fluorescent tube. It is composed of a metal sintered body and mercury that is combined therewith.

In another mercury release structure, a magnetic material powder containing iron as a main component is mixed into a metal sintered body, and when inserted into a glass bulb, the mounting at a fixed position is moved by a magnet. It is made possible.

One method of manufacturing the mercury-releasing structure of the present invention is to solidify one or more kinds of metal powders into a size that can be inserted into a glass bulb, and form a metal sintered body by heating. Are heated in a vacuum heating vessel.

Another method of manufacturing a mercury-releasing structure according to the present invention is as follows. A metal sintered body and mercury are sealed in a small vacuum vessel, placed in a heating vessel and heated to form a metal sintered body and mercury. Combined with mercury.

In the fluorescent discharge tube of the present invention, the mercury-releasing structure is used also as a main electrode so as to serve as a main electrode after the mercury is released, or the mercury-releasing structure is used only for the purpose of mercury release.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is obtained by solidifying and sintering one or more kinds of metal powders such as nickel, titanium, tantalum and the like into a size that can be inserted into the glass bulb. A metal sintered body, mercury and the metal sintered body are combined by heat treatment, and the mercury is released into the glass bulb by being inserted into the glass bulb and then heated. Since the mercury emission structure is suitable for use in a fluorescent discharge tube and is configured to have dimensions that can be inserted into a glass bulb in advance, there is no need to perform a processing for cutting into a dimension that can be inserted into the bulb.

According to a second aspect of the present invention, the mercury releasing structure is also used as one of the main electrodes, and can be used as a main electrode after mercury release.

In the invention according to claim 3 of the present invention, the pair of main electrodes also serves as a mercury release structure, and after mercury release, can be used as a pair of main electrodes.

According to a fourth aspect of the present invention, the pair of electrode mounts includes a pair of metal rods sealed at both ends of a glass bulb, and one of the pair of metal rods located inside the glass bulb. Is a mercury-releasing structure attached to the tip of the device, and the mercury-releasing structure can be used as a main electrode after mercury release.

According to a fifth aspect of the present invention, one of the electrode mounts is sealed at one end of a glass bulb longer than the entire length of the completed fluorescent discharge tube, and the other of the electrode mounts is not sealed. After the mercury release of the mercury release assembly placed between the position of the other electrode mount and the other end of the glass bulb, the other electrode mount is placed A mercury emitting structure adapted for use with a fluorescent discharge tube sealed to the glass bulb,
Since it is configured to have dimensions that can be inserted into the glass bulb in advance, there is no need to perform a processing for cutting into dimensions that can be inserted into the bulb.

According to a sixth aspect of the present invention, there is provided a metal sintered body obtained by solidifying and sintering one or more kinds of metal powders such as nickel, titanium, tantalum and the like into a size capable of being inserted into the glass bulb. After preparing, a method for producing a mercury-releasing structure obtained by electrically heating a vacuum heating vessel containing a metal sintered body and mercury from the outside to combine the metal sintered body and the mercury, Since it is configured to have dimensions that can be inserted into the glass bulb in advance, there is no need to perform a processing for cutting into dimensions that can be inserted into the bulb.

According to a seventh aspect of the present invention, there is provided a metal sintered body obtained by solidifying and sintering one or more kinds of metal powders such as nickel, titanium, tantalum and the like into a size capable of being inserted into the glass bulb. After the above, the metal sintered body and mercury are mixed in a small container, the small container is evacuated, the small container in the vacuum state is placed on the heating container, and the small container is heated at the heat generation temperature of the heating container. This is a method for producing a mercury release structure obtained by heating and combining the metal sintered body and the mercury. Since the structure is configured in advance so that it can be inserted into a glass bulb, it is cut into dimensions that can be inserted into the bulb. No processing is required.

According to an eighth aspect of the present invention, in the mercury release structure, one of the electrode mounts is sealed at one end of a glass bulb longer than the entire length of the completed fluorescent discharge tube, and After mercury release of the mercury-releasing assembly mounted at a position equal to the entire length of the fluorescent discharge tube to be completed without being sealed and between the position of the other electrode mount and the other end of the glass bulb The other electrode mount is a mercury emission structure suitable for use in a fluorescent discharge tube sealed in the glass bulb, and includes one or more metal powders such as nickel, titanium and tantalum and a magnetic powder mainly composed of iron. A metal sintered body obtained by sintering a mixed powder, and a product obtained by combining mercury and the metal sintered body by a heat treatment, and a mercury release structure in the glass bulb is magnetized from outside the glass bulb. By Since it is moved, it is configured in such a size that it can be inserted into the glass bulb in advance, so there is no need for processing to cut it into dimensions that can be inserted into the bulb, and since it contains a magnetic material, it has a mercury release structure Can be easily moved.

According to a ninth aspect of the present invention, there is provided a metal sintered body obtained by solidifying and sintering one or more kinds of metal powders such as nickel, titanium, and tantalum into a size capable of being inserted into the glass bulb. Is a fluorescent discharge tube in which a mercury-releasing structure obtained by combining and mercury by a heat treatment is also used as one of the pair of main electrodes, and the mercury-releasing structure is cut into dimensions that can be inserted into the bulb. Becomes unnecessary.

According to a tenth aspect of the present invention, the pair of electrode mounts sealed at both ends of the glass bulb includes a pair of metal rods sealed at both ends of the glass bulb, and a pair of metal rods mounted inside the glass bulb. And a pair of main electrodes attached to the tips of a pair of metal rods. One or more types of metal powders such as nickel, titanium, and tantalum are solidified and sintered to a size that can be inserted into the glass bulb. A fluorescent discharge tube in which a mercury-releasing structure obtained by combining a metal sintered body and mercury by heat treatment is also used as the pair of main electrodes, and the mercury-releasing structure is cut into dimensions that can be inserted into a bulb. Becomes unnecessary.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a perspective view of a mercury emitting structure adapted for use with the fluorescent discharge tube of the present invention, 1 is a hollow cylindrical mercury emitting structure, and 2 is a metal rod of an electrode mount (not shown).
Is a hole to be inserted. The mercury releasing structure 1 is configured by solidifying one or more kinds of metal powders such as nickel, titanium, tantalum, and the like in a mold, and combining mercury with a metal sintered body sintered at a high temperature of about 900 ° C.

FIG. 2 shows a method of manufacturing the mercury-releasing structure of the present invention. First, as shown in FIG. 2 (a), one or a plurality of fine metal powders 3 of titanium, tantalum, nickel or the like are used. Is heated in a mold at a temperature of sintering a solid, for example, about 900 ° C. for about 10 minutes to 1 hour to produce a metal sintered body 4.

Next, as shown in FIG. 2B, the metal sintered body 4 and the mercury 5 are put in the heating vessel 6, and the inside of the heating vessel 6 is evacuated by the vacuum pump 7. In this state, the high-frequency coil 8 circulated around the heating vessel 6 is energized, and
The metal sintered body 4 and the mercury 5 are combined by heating at a temperature of about 00 ° C. for a long time, for example, about 12 to 15 hours. afterwards,
After the heating vessel 6 and the metal sintered body 4 combined with mercury are cooled, the metal sintered body 4 is taken out from the heating vessel 6, and the metal sintered body 4 is combined with mercury 5 as shown in FIG. The mercury emission structure 1 is completed.

In this embodiment, the metal sintered body 4 and the mercury 5 are sealed in the heating vessel 6, but if a large heating vessel 6 is used, it takes a long time to make the inside of the vessel a vacuum state. become. FIG. 3 considers this point. First, as shown in FIG. 3A, the metal sintered body 4 and the mercury 5 are inserted into a small, for example, a glass container 9 from an exhaust pipe 10,
After evacuating the glass container 9 by the vacuum pump 7, the exhaust pipe 10 is melted and sealed. Next, as shown in FIG.
For example, it may be placed in an electric furnace that generates heat by the tungsten heater 12 and heated at a high temperature of the furnace. Although the small container 9 is a glass container, a small metal container may be used.

FIG. 4 is a structural view of a fluorescent discharge tube of the present invention using such a mercury emitting structure 1. Reference numeral 13 denotes a glass bulb, and reference numerals 14 and 15 denote metal rods sealed at both ends of the bulb.
Reference numeral 6 denotes a main electrode for attaching a metal sintered body obtained by sintering one or more kinds of fine metal powders of titanium, tantalum, nickel or the like to a metal rod by caulking, welding, or the like. Further, the mercury releasing structure 1 is attached to the metal rod 14 by, for example, caulking. Although not shown, the fluorescent discharge tube including such a configuration is provided with a fluorescent film on the inner surface of the glass bulb as is well known,
A predetermined amount of argon or neon gas is sealed inside the valve.

By the way, in order to release and diffuse mercury into the bulb of the fluorescent discharge tube, if the area where the mercury release structure 1 is mounted is heated with high frequency from outside the bulb, the mercury compounded with the metal sintered body can be released. Evaporates and is released into the valve. After mercury evaporates and is released from the mercury-releasing structure 1, the mercury-releasing structure 1 is mainly composed of a sintered body of titanium, tantalum, nickel, or the like, which can be used as a main electrode of a fluorescent discharge tube. 1 can also be used as the main electrode.

FIG. 5 is a block diagram showing another embodiment of the fluorescent discharge tube using the mercury releasing structure of the present invention.
Is a glass bulb, 18 and 19 are metal rods, 20 and 21 are metal sintered bodies of the above-mentioned metal powders such as titanium, tantalum, nickel, etc., which become main electrodes attached to the tips of the metal rods, and 22 is a metal rod. Figure 4 shows a bead glass installed.

In the figure, an electrode mount comprising a metal rod 18 and a main electrode 20 is sealed at one end of a glass bulb 17, and an electrode 21 and a bead glass 22 are placed in the glass bulb 17 which is longer than the entire length of the completed fluorescent discharge tube. Is mounted on the entire length of the fluorescent discharge tube to be completed, and the mercury release structure 23 is disposed at the position shown in the figure. As described above, the inside of the glass bulb 17 is provided with a fluorescent film on the inner surface of the bulb, and a predetermined amount of argon or neon gas is sealed in advance.

In this state, when heating is performed by a high-frequency coil (not shown) from the outside of the bulb 17 located at the position of the mercury release structure 23, the mercury evaporates as described above, and the electrode not sealed with the bulb 17 is heated. Through the gap between the bead glass 22 of the mount and the inner wall of the bulb, mercury is diffused into the glass bulb of the completed fluorescent discharge tube.

Thereafter, the bead glass 22 and the glass bulb 17 are heated and welded, and the unnecessary portion 24 of the glass bulb is welded.
Is cut to complete the fluorescent discharge tube. The unnecessary portion of the glass bulb is safe because the mercury diffused inside is not released to the outside if both ends of the bulb are sealed. In this embodiment, since the mercury releasing structure is used only for the purpose of releasing mercury, there is no need to provide a hole supported by a metal rod as shown in FIG. When the mercury-releasing structure 23 is used only for mercury release as in the embodiment of FIG. 5, it is preferable to arrange the mercury-releasing structure 23 at the fixed position of the glass bulb 17 as much as possible.

FIG. 6 shows an embodiment of a fluorescent discharge tube using a mercury emitting structure 25 manufactured in consideration of the above points.
This mercury releasing structure 25 is obtained by mixing magnetic powder such as iron or an iron compound with one or more kinds of fine metal powder serving as a base, such as tantalum, titanium, and nickel, as described in FIG. It is made by combining mercury with a metal sintered body that has been solidified in a mold and sintered. When such a mercury release structure 25 is sealed in the glass bulb 17 and its position is determined, if the magnet 26 is brought close to the bulb 17 from the outside of the bulb 17, since the mercury release structure 25 contains a magnetic material, the mercury release structure 25 is released. The structure 25 is attracted to the magnet 26 and thus the magnet 2
6 in the direction of the arrow to release the mercury release structure 2.
5 also moves in the direction of the arrow in the glass bulb, so that its position can be localized.

The ratio of the magnetic material contained in the mercury releasing structure 25 may be determined in consideration of the thickness of the glass bulb, the magnitude of the magnetic force of the magnet used, and the like. By the way, even if the ratio of the magnetic material of iron or an iron compound is 20% by weight with respect to 100% by weight of the mixed fine powder of titanium, tantalum and iron of the mercury releasing structure, the inside of the valve can be moved sufficiently, Requires a considerable amount of magnetic force.
Naturally, if the proportion of the magnetic material in the mercury releasing structure is further increased, for example, to 50% by weight, a magnet having a small magnetic force is sufficient. Further, when the proportion of the magnetic material in the mercury-releasing structure is, for example, 20% by weight and 50% by weight, the amount of mercury emission is slightly affected, but does not pose a problem.

In the embodiment according to FIGS. 5 and 6 described above, the electrode mount is formed by attaching a sintered body electrode to a rod-shaped metal. As long as there is no problem with the function, there is no problem.

[0037]

As described above, the mercury-releasing structure used in the fluorescent discharge tube of the present invention is prepared by preparing a metal sintered body in a shape to be used in advance, and merging it with mercury. For insertion into the glass bulb of the fluorescent discharge tube, for example, there is no need to perform a work such as cutting in accordance with the inner diameter of the bulb, and a stable amount of mercury can be released and diffused into the bulb.

After mercury is released, mercury can be combined with a metal sintered body obtained by sintering a metal powder that can be used as an electrode of an electrode mount. can do.

Furthermore, if a powder of a magnetic substance such as iron, ferric carbide, or ferric nitride is mixed in a sintered metal body, the mercury-releasing structure can be placed at a fixed position on a glass bulb. The mercury emission structure can be moved by the operation of the magnet from the outside of the bulb and placed at a predetermined position, and the mercury can be emitted into the bulb of the completed fluorescent discharge tube.

[Brief description of the drawings]

FIG. 1 is a perspective view of a mercury release structure used in a fluorescent discharge tube of the present invention.

FIG. 2 (a) is a state diagram showing a method for manufacturing a mercury-releasing structure of the present invention, showing a manufacturing process of a metal sintered body. (B) is a diagram showing a method for manufacturing a mercury-releasing structure of the present invention. State diagram showing the production process for mercury compounding

FIG. 3 (a) In another embodiment of the method for producing a mercury-releasing structure used for a fluorescent discharge tube of the present invention, a metal sintered body and mercury are sealed in a small container, and the inside is evacuated. (B) In another embodiment of the method for manufacturing a mercury-releasing structure used in a fluorescent discharge tube of the present invention, a small container in which a metal sintered body and mercury are inserted is heated in a heating container. State diagram

FIG. 4 is a configuration diagram of a fluorescent discharge tube using the mercury release structure of the present invention.

FIG. 5 is a configuration diagram showing another embodiment of a fluorescent discharge tube using the mercury release structure of the present invention.

FIG. 6 is a configuration diagram showing still another embodiment of the fluorescent discharge tube using the mercury release structure of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mercury release structure 3 Metal powder 4 Metal sintered body 5 Mercury 6 Heating vessel 7 Vacuum pump 8 High frequency coil 9 Small vessel 10 Exhaust pipe 11 Heating vessel 13, 17 Glass bulb 14, 15 Metal rod 16 Main electrode 18, 19 Metal rod 20, 21 Main electrode 22 Bead glass 23, 25 Mercury emission structure 26 Magnet

Claims (10)

[Claims] 1. A fluorescent discharge tube comprising a pair of electrode mounts sealed at both ends of a glass bulb, a fluorescent film applied to an inner wall of the glass bulb, and a rare gas sealed in the glass bulb. A mercury-releasing structure that releases mercury into a metal sintered body obtained by solidifying and sintering one or more kinds of metal powders such as nickel, titanium, and tantalum into a size that can be inserted into the glass bulb; And a mercury-releasing structure suitable for use in a fluorescent discharge tube that emits mercury into the glass bulb by being inserted into the glass bulb and then heated to emit mercury into the glass bulb. 2. A pair of electrode mounts, comprising: a pair of metal rods sealed at both ends of the glass bulb; and a pair of main electrodes attached to tips of the pair of metal rods located in the glass bulb. 2. The mercury-releasing structure according to claim 1, wherein one of the pair of main electrodes is a mercury-releasing structure, and can be used as an electrode after mercury is released. 3. A pair of electrode mounts, comprising: a pair of metal rods sealed at both ends of the glass bulb; and a pair of main electrodes attached to tips of the pair of metal rods located in the glass bulb. 2. The mercury-releasing structure according to claim 1, wherein the pair of main electrodes also serve as a mercury-releasing structure, and can be used as an electrode after mercury is released. 4. A pair of electrode mounts, one of which is a first metal rod sealed at one end of the glass bulb, and the other is a second metal rod sealed at the other end of the glass bulb. And a mercury-releasing structure attached to the tip of the second metal bar located inside the glass bulb, wherein the mercury-releasing structure is used as an electrode after mercury release.
A mercury-releasing structure suitable for use in the fluorescent discharge tube according to claim 1. 5. A pair of electrode mounts, comprising: a pair of metal rods;
One of the electrode mounts is sealed to one end of a glass bulb that is composed of a pair of main electrodes attached to the tip of the metal rod located in the glass bulb and that is longer than the entire length of the completed fluorescent discharge tube, The other of the pair of electrode mounts is placed at a position equal to the entire length of the fluorescent discharge tube to be completed without being sealed, and a mercury emission structure is provided between the position of the other electrode mount and the other end of the glass bulb. The mercury-releasing structure according to claim 1, wherein the mercury-releasing structure is mounted and the other electrode mount is sealed to the glass bulb after mercury release of the mercury-releasing structure. 6. A pair of electrode mounts is sealed at both ends of a glass bulb, a fluorescent film is applied to an inner wall of the glass bulb, and a rare gas is sealed in the bulb. A method for producing a mercury-releasing structure that releases mercury into a glass bulb, comprising: solidifying and sintering one or more kinds of metal powders such as nickel, titanium, and tantalum in a size that can be inserted into the glass bulb. A sintered body is prepared, and then the heating vessel in which the metal sintered body and mercury are mixed is evacuated, and the heating vessel in a vacuum state is electrically heated from the outside to form the metal sintered body and the mercury. And a method for producing a mercury-releasing structure. 7. A pair of electrode mounts are sealed at both ends of a glass bulb, a fluorescent film is applied to an inner wall of the glass bulb, and the glass bulb is inserted into a fluorescent discharge tube in which a rare gas is sealed in the bulb. A method for manufacturing a mercury-releasing structure for releasing mercury into a bulb, comprising: solidifying and sintering one or more kinds of metal powders of nickel, titanium, tantalum, or the like into a size capable of being inserted into the glass bulb. A sintered body is formed, and then, the metal sintered body and mercury are mixed in a small container, the container is evacuated, the small container in the vacuum state is placed on a heating container, and the heating temperature of the heating container is changed. A method for producing a mercury releasing structure, wherein the small container is heated to combine the metal sintered body and the mercury. 8. The glass bulb having one end sealed with one end of the glass bulb and the other end sealed with the other end of the glass bulb from the position of the one electrode mount to a predetermined position. A mount is mounted, and a mercury releasing structure is mounted between the other electrode mount and the other end of the glass bulb, and the other electrode mount is mounted on the glass bulb after mercury is released by heating the mercury releasing structure. In a fluorescent discharge tube obtained by sealing and cutting unnecessary portions of the glass bulb, the mercury-releasing structure is formed of one or more metal powders such as nickel, titanium, and tantalum and a magnetic powder mainly containing iron. A metal sintered body obtained by sintering the mixed powder;
The use of a fluorescent discharge tube, which is formed by combining mercury and the metal sintered body by a heat treatment, and in which a mercury releasing structure in the glass bulb is moved by a magnet from outside the glass bulb. Mercury emitting structure suitable for. 9. A fluorescent discharge tube in which a pair of electrode mounts are sealed at both ends of a glass bulb, a fluorescent film is applied to an inner wall of the glass bulb, and a rare gas is sealed in the bulb. The mount includes a pair of metal rods sealed at both ends of the glass bulb, and a pair of main electrodes attached to tips of the pair of metal rods located in the glass bulb, and includes nickel, titanium, and tantalum. A metal-sintered body obtained by solidifying and sintering a metal sintered body obtained by solidifying and sintering one or more kinds of metal powders into a size capable of being inserted into the glass bulb, and mercury by heat treatment. A fluorescent discharge tube used as an electrode after mercury release of the mercury release structure. 10. A pair of electrode mounts is sealed at both ends of a glass bulb, and a fluorescent film is applied to an inner wall of the glass bulb.
In the fluorescent discharge tube in which the rare gas is sealed in the bulb, the pair of electrode mounts includes a pair of metal rods sealed at both ends of the glass bulb, and the pair of metal rods located in the glass bulb. A metal sintered body comprising a pair of main electrodes attached to the tip of a rod, and solidifying and sintering one or more kinds of metal powders such as nickel, titanium, tantalum and the like into a size that can be inserted into the glass bulb. A mercury-releasing structure obtained by combining a mercury and a mercury by a heat treatment also as the pair of main electrodes, and the mercury-releasing structure is used as an electrode after mercury is released.