JPH0721974A - Barium azide for tube and tube - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide an activator (electron emissive substance), a getter and a tube which can reduce various impurities remaining in a valve and improve various characteristics and life characteristics. [Constitution] When the amount of barium carbonate contained is 2% by weight or less or the amount of barium hydroxide is 6% by weight or less, or when the amount of barium carbonate contained is X% by weight and the amount of barium hydroxide is Y% by weight, The total amount of both is 3X weight% + 1Y
A barium azide for a tube having a weight% of <6% by weight and a tube having the barium azide provided on an electrode. [Operation] Since the amount of impurities contained in barium azide is very small, no undecomposed portion remains in barium recrystallized by thermal decomposition, no impure gas is generated, and barium is strongly adhered. It

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to barium azide used as an easily dischargeable (active) substance or as a getter material in a bulb and a bulb provided with this barium azide in an electrode portion.

[0002]

2. Description of the Related Art Conventionally, in a starting tube, a discharge lamp or the like, a material called an electron emissive substance or an activator is provided on a discharge electrode in order to facilitate discharge at the time of starting.
Further, even in light bulbs, a getter is provided in the bulb in order to increase the degree of vacuum in the bulb and to remove impure gas, which is essential in these bulbs.

There are various materials as these electron emitting (active) substances and getters, but barium azide (Ba (N
₃ ) Since ₂ ) is water-soluble and easy to handle, and because it exerts an active action at relatively low temperatures, it is used in many bulbs including lighting tubes.

For example, when barium is to be formed on the electrodes of a lighting tube, barium azide is mixed in pure water and milled to form a liquid slurry, the electrodes are immersed in this slurry, and the slurry is pulled up, dried and re-formed. After being deposited by crystallization and sealing the electrode in the bulb, the bulb is evacuated in the evacuation process and heated at a relatively low temperature while being evacuated to decompose the barium (Ba) film on the electrode surface. It is covered.

Since barium azide can be decomposed at a low temperature in this way, it is possible to safely carry out the work without forcing the bimetal electrode of the lighting tube, which deteriorates the thermal response characteristics when heated to a high temperature.

There are various lighting systems for discharge lamps such as fluorescent lamps, but the lighting system using this kind of lighting tube as a starting aid is simple in construction and inexpensive, and is used for many purposes including household lighting. Is used for. Recently, there is a high demand for quality from users, and there is a demand for the lamp to be lit as quickly as possible even if it is not instantaneously lit by the rapid start method.

[0007] In addition, the life of the lighting tube is blinking 500
Although it is set to 0 times or more, there are cases in which the lamp cannot be lit because the number of times is not reached or the life of the lamp is shortened by restarting the lighting tube.

In view of such circumstances, the present inventors have conducted various studies to improve the characteristics of the lighting tube, and as a result, have focused on barium azide as a raw material.

Barium azide, which is a conventional raw material for producing barium, is not limited to barium azide when carbon dioxide gas in the air is absorbed during the concentration process or when the synthesis reaction is insufficient during the production process of the raw material. It contained a large amount of barium compounds such as barium and barium hydroxide.

Since these barium carbonate, barium hydroxide and the like have a higher decomposition temperature than barium azide, decomposition is suppressed in the manufacturing process in which the conditions were adjusted with barium azide, resulting in insufficient decomposition and deterioration of lighting tube characteristics. . (Turning time TS increases.) Further, since barium carbonate or barium hydroxide is present, the crystal growth of barium azide is suppressed, and fine particles increase during coating, and peeling easily occurs. (Because the film binding force becomes stronger than the film adhesion force) If the adhesion of barium (Ba) to the electrode after barium azide thermal decomposition is weak, barium may sputter due to glow discharge during lighting operation, It is easily detached by a mechanical shock, and the period until the electrode activation function is lost, that is, the life is extremely shortened.

Further, if the decomposition temperature rises, the decomposition is delayed, and undecomposed matter remains in the lighting tube, and this residue produces impure gas and the like, which causes deterioration of the characteristics of the lighting tube at an early stage. is there.

[0012]

As described above, the conventional barium azide has a large amount of impurities and cannot obtain higher characteristics.

[0013]

The barium azide for a bulb according to claim 1 of the present invention is characterized by containing barium carbonate in an amount of 2% by weight or less.

The barium azide for a bulb according to a second aspect of the present invention is characterized in that the amount of barium hydroxide contained is 6% by weight or less.

When the amount of barium carbonate contained is X% by weight and the amount of barium hydroxide is Y% by weight, the total amount of both is 3X. It is characterized in that weight% + 1Y weight% <6 weight%.

The tube according to claim 4 of the present invention is characterized in that the electrode is provided with the barium azide according to any one of claims 1 to 3.

The bulb according to claim 5 of the present invention is a lighting tube.

The bulb according to claim 6 of the present invention is a discharge lamp. The bulb according to claim 7 of the present invention is a light bulb.

[0019]

[Function] Since the amount of impurities contained in barium azide is very small, no undecomposed portion remains in barium recrystallized by thermal decomposition, no impure gas is generated, and barium is strongly adhered. To be done.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a starting tube 1 used for starting a discharge lamp such as a fluorescent lamp. In this lighting tube 1, a stem 3 in which two lead wires 4 and 5 are planted in parallel with each other is attached to one end of a glass tube bulb 2, one lead wire 4 is a fixed electrode, and the other lead wire 5 is attached. One end of a bimetal bent in a V shape is fixed to form the movable electrode 6. Argon gas (Ar) is enclosed in the valve 1.

The glass tube bulb 2 is housed in a bottomed cylindrical plastic cap 7, and
The lead wires 4 and 5 are connected to a base 8 attached so as to cover the opening of the cap 7.

Then, the lead wires 4 and 5 planted in the stem 3 and the movable electrode 6 made of a V-shaped bimetal.
Barium (Ba) 10 is coated on the surface of the.

The manufacturing of the lighting tube 1 having such a structure is the same as the usual method, but first, barium azide containing a small amount of impurities, for example, as a result of purification, about 1% by weight of barium carbonate and barium hydroxide are prepared. About 2% by weight was selected and prepared. Then, this barium azide is mixed in pure water to perform milling, and then a liquid slurry is prepared, and both electrodes 4, 5, and 6 formed on the stem 3 are dipped in the slurry, pulled up, and dried. By doing both electrodes 4,
Barium azide is coated on the surface of 5 and 6 parts.

Next, the stem 3 is sealed on one end side of the glass tube bulb 2, and while heating the bulb 2 from the outside, the inside of the bulb 2 is exhausted and the impure gas adsorbed on the inner wall is released and removed. By this heating, about 2 parts of barium azide (Ba (N ₃ ) ₂ ) coated on the surfaces of both electrodes 4, 5, and 6 was used.
Decomposes at 10 ° C. As a result, barium azide (Ba
(N ₃ ) ₂ is decomposed as Ba (N ₃ ) ₂ → Ba + 3N ₂ and barium (Ba) is formed on the surfaces of both electrodes 4, 5, and 6.
10 is coated.

Thereafter, the valve 2 is filled with argon gas, the other end of the valve 2 is melt-sealed, and the outer end portions of both the lead wires 4 and 5 are connected to the terminals of the base 8 to form the cap 7. If covered, the lighting tube 1 is completed.

In such a lighting tube 1, there is no barium compound or the like remaining in the barium (Ba) 10 formed on the surfaces of the electrodes 4, 5, and 6, or even if there is any, no trace amount of impure gas is generated. The starting characteristic of the lighting tube 1 can be maintained for a long period of time. Further, since barium azide containing a small amount of impurities is recrystallized almost uniformly over the whole, it has a strong bonding force with the surfaces of the electrodes 4, 5 and 6, and the coating 10
It was possible to extend the service life of the product without dropping off due to discharge or mechanical shock.

The barium (Ba) 10 coated on the electrodes 4, 5 and 6 is preferably pure barium, but it is difficult to obtain barium azide having no impurities at all in terms of cost, and the present inventors As shown in FIGS. 2 and 3, the result of the test No. 2 is less than 2% by weight if the mixture of barium azide is only barium carbonate or less than 6% by weight if it is only barium hydroxide. Then, it turns out that it operates faster than the current product.

That is, the required lighting time TS (seconds) (the time from the start of energization until the fluorescent lamp is turned on), which is a characteristic of the lighting tube, is within 7 seconds according to Japanese Industrial Standard JIS-C7603 (temperature 20 to 27 ° C.). Then, the average of the conventional product was about 5 seconds, while the average was about 3 seconds.

The inventors of the present invention have investigated the lighting required time TS (seconds) by changing the content ratios of barium carbonate and barium hydroxide contained in barium azide, and as shown in FIGS. 2 and 3. I got good results.

FIG. 2 shows barium carbonate, and FIG. 3 contains barium hydroxide. The horizontal axis shows the ambient temperature (° C.) and the vertical axis shows the required lighting time TS (seconds).

Even if the lighting tube 1 is the same lighting tube, the required lighting time TS (second) varies depending on the ambient temperature (° C.) because it is a thermo-responsive element, and the higher the temperature, the shorter the starting time, but the special case is excluded. Within the normal room temperature range of 5 to 30 ° C, J
If the voluntary target of starting within 5 seconds, which exceeds the IS standard, is 2% by weight or less in the case of barium carbonate and 6% by weight or less in the case of barium hydroxide, this can be satisfied.

In addition, in the experiments conducted by the present inventors, when both barium carbonate and barium hydroxide were contained, if the total amount of both was 3X wt% + 1Y wt% <6 wt%, the same as above. The result was obtained.

This is because if a large amount of barium carbonate or barium hydroxide, which has a higher recrystallization temperature than barium azide, remains in the bulb of the ignition tube without being decomposed, oxygen, hydrogen, carbon dioxide gas or the like is discharged in the bulb. A large amount of impure gas that remains is also left behind, which prolongs the starting time of the ignition tube, deteriorates its characteristics, and causes a short service life. It is necessary to keep the content rate below the above. In addition, if the decomposition temperature is raised in anticipation of barium carbonate or barium hydroxide contained in the barium azide, the bimetal forming the movable electrode of the lighting tube is overheated, resulting in excessive deformation. This is not preferable because the discharge interval is disturbed and the starting characteristics are deteriorated.

Further, barium azide is attached to the surface of the cane glass portion where the anchor of the light bulb mount is implanted, the anchor and the surface of the lead wire, and is used as a getter for adsorbing the impure gas in the bulb by heating from the filament. If the amount of barium carbonate or barium hydroxide contained in barium azide is also within the above range when used for a light bulb,
The degree of vacuum inside the valve is better than before, oxygen, hydrogen,
It is possible to eliminate defective impurities such as carbon dioxide gas in the bulb and improve the working characteristics and life of the light bulb.

The present invention is not limited to the above embodiment. For example, it may be used not only as an activator for a lighting tube or as a getter for a light bulb, but also as an electron emissive substance or a getter for a discharge lamp. Applicable to a wide range of tubes.

[0036]

As described in detail above, according to the present invention, no impure gas is generated in the bulb valve, the characteristics are improved, and the life is extended.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of a lighting tube.

FIG. 2 Atmosphere temperature (° C.) and starting time TS according to the barium carbonate content of barium azide formed on the electrodes of the lighting tube
It is a graph which compares with (second) and shows.

[Fig. 3] Atmosphere temperature (° C) and starting time T for each content ratio of barium hydroxide in barium azide formed on the electrode of the lighting tube
It is a graph which compares with S (second) and shows.

[Explanation of symbols]

 1: Lighting tube (bulb) 2: Valve 3: Stem 4: Fixed electrode (lead wire) 5: Lead wire 6: Movable electrode (bimetal)

Claims (7)

[Claims] 1. Barium azide for a bulb characterized in that the amount of barium carbonate contained is 2% by weight or less. 2. The amount of barium hydroxide contained is 6% by weight.
Barium azide for a tube characterized by the following: 3. The amount of barium carbonate contained is X% by weight,
A barium azide for a bulb characterized in that when the amount of barium hydroxide is Y% by weight, the total amount of both is 3X% by weight + 1Y% by weight <6% by weight. 4. A bulb comprising an electrode provided with the barium azide according to any one of claims 1 to 3. 5. A bulb according to claim 4, wherein the bulb is a lighting tube. 6. A tube according to claim 4, which is a discharge lamp. 7. A tube according to claim 4, which is a light bulb.