JP3343363B2 - Tube ball - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for purifying impurities in a bulb of a fluorescent lamp or an incandescent lamp.

[0002]

2. Description of the Related Art Recently, a three-wavelength light-emitting fluorescent material has been used as a fluorescent material for a rapid-start fluorescent lamp. The rapid start type fluorescent lamp is formed by forming a transparent conductive film (EC film = Nesa film) on the inner surface of an arc tube bulb and forming a fluorescent film on the inner surface of the EC film. Since the Nesa film plays a role of reducing the tube wall resistance, it has a characteristic that the starting is easy. The use of a three-wavelength light-emitting phosphor as a phosphor has an advantage that high luminance and high color rendering can be obtained. However, in this type of rapid-start fluorescent lamp, some lamps have a high starting voltage Vs.

There are various causes for the increase of the lighting start voltage. One of them may be affected by the impurity gas in the bulb. It has been found that the lighting start voltage Vs of ordinary fluorescent lamps increases when impurities such as carbon dioxide CO, carbon monoxide CO ₂ and moisture H ₂ O are present in the bulb.

For this reason, various measures have been taken to prevent the impurity gas from remaining in the bulb during the process of manufacturing the lamp. For example, the bulb wall and mount components are heated, or the bulb wall is replaced by a method such as gas replacement. Care is taken not to release impurities adhering or adsorbed to the mounting member or to the mounting member, nor to adhere or adsorb impurities to the phosphor. However, these measures are not perfect. In some cases, impurities may be knocked out from the bulb wall or mount components during lighting, and furthermore, an electron emitting material (emitter) such as barium Ba applied to the electrode may be used. When activated by heating, CO, CO ₂ and H ₂ O may be emitted from this emitter. Therefore, it is impossible to completely prevent CO and CO _{2 from} being released into the valve.

On the other hand, in the case of an incandescent light bulb, for example, a light bulb used for a traffic signal light, there are lamps whose life characteristics are greatly reduced due to subtle changes in the exhaust state. In the case of an incandescent light bulb, if moisture H ₂ O remains in the bulb, there is a problem that the filament causes a water cycle to cause early disconnection. Although a getter or the like is used to prevent such a water cycle, there are disadvantages such as insufficient water absorption performance and high cost.

[0006] In the case of incandescent bulbs, even if oxygen, nitrogen or CO and CO ₂ may remain, but much less affected the less its residual amount is required to be avoided residual moisture H ₂ O is even slightly is there.

[0007]

That is, in any of the fluorescent lamps and the incandescent lamps, if impurities remain in the bulb, problems such as an increase in starting voltage and a decrease in life characteristics are caused. There is a demand for eliminating such residual impurities.

The present invention has been made in view of such circumstances, and an object thereof is to provide a bulb in which impurities such as CO, CO ₂ and H ₂ O do not remain in a valve. Is what you do.

[0009]

A tube according to claim 1 is
Almost all the surface of the valve, met the particle size charging tendency for reduced iron powder 44~74μm is + 3.0μC / g or more
A powder made of ultrafine particles having a specific surface area of 100 m ² / g or more . According to a second aspect of the present invention, the powder according to the first aspect is characterized in that the powder of the first aspect is adhered to the surface of the phosphor powder of the phosphor film formed on substantially the entire inner surface of the bulb. A tube according to a third aspect is characterized in that the powder according to the first or second aspect has a pH of 9 or more in a 20% by weight aqueous solution. The tube according to claim 4 is a powder according to any one of claims 1 to 3,
It is characterized by being made of at least one oxide of Mg, Ca, Sr, Ba and Zn.

[0010]

According to the tube of the first aspect, the particle diameter is 44 to
The charging tendency for the reduced iron powder of 74 μm is +3.0 μC /
g or more , and the specific surface area is 100 m ² / g or more.
The powder composed of particles adsorbs impurities in the valve and prevents CO, CO ₂ and H ₂ O from remaining in the valve. Therefore, in the case of an incandescent lamp, the life characteristics are improved.
Further, in the case of a fluorescent lamp in which a fluorescent film is formed on almost the entire inner surface of the bulb as described in claim 2, the starting voltage can be reduced,

According to the tube of the third aspect, 20% by weight.
A powder having a pH of 9 or more in an aqueous solution of water adsorbs impurities in the valve, and CO, CO ₂ and H ₂ O
And so on. Also in this case, when applied to a fluorescent lamp, the starting voltage can be reduced, and when used for an incandescent lamp, the life characteristics are improved. Further, according to claim 4
According to the bulb, the powder is made of Mg, Ca, Sr, Ba, Zn.
Since it is made of at least one kind of oxide,
The charging tendency specified in claim 1 can be easily obtained.
You.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

The drawings show a straight tube rapid start fluorescent lamp, 1 being a glass bulb. Both ends of the valve 1 are airtightly closed by flared stems 2, 2, and a pair of leads 3.

A hot cathode made of tungsten or the like, that is, a filament 4, 4 is stretched between the lead wires 3, 3 of the stems 2, 2. The filaments 4, 4
Although not shown, an electron emitting material such as barium oxide is applied to the substrate.

A transparent conductive film (EC film = Nesa film) 5 such as tin oxide is formed on the inner surface of the bulb 1, and a phosphor coating 6 is formed on the surface of the transparent conductive film 5. Are formed. The phosphor coating 6 uses a three-wavelength phosphor, specifically, Y ₂ O ₃ : Eu (red), (Re, Tb, Ce). (P, Si) O ₄ (green) ) (Where Re is a rare earth element) and BaMg ₂ Al ₁₁
O ₂₇ : It is constituted by mixing each phosphor powder of Eu (blue).

The phosphor has a specific surface area of 100 m ^2.
/ G or more of metal oxide ultra-fine particles are adhered. That is, as shown in FIG.
0, a powder 2 of a metal oxide such as MgO
0, and the powder 20 has a specific surface area of 10
0m ² / G or more, whereby the metal oxide powder 20 has a pH of 9 or more (alkaline) in a powder having a charging tendency of +3.0 μC / g or more or a 20% by weight aqueous solution.

As shown in FIG. 2, the charge tendency of the metal oxide has a property of being positively charged and a property of being negatively charged depending on the type, and MgO is positively charged.
O ₂ tends to be negatively charged. In place of Mg, at least one metal oxide selected from oxides of Ca, Sr, Ba, and Zn has a positive charge tendency. Also, instead of SiO ₂ , Sn, Ti, G
At least one selected from the oxides of e, Ta, Nb, V, and Mo has a negative charge tendency.

In this embodiment, the powder 20 having a positive charge tendency and having a charge tendency of +3.0 μC / g or more for reduced iron powder having a particle diameter of 44 to 74 μm is used.

Such a powder 20 has such a property that the pH thereof when dissolved in a 20% by weight aqueous solution becomes 9 or more (alkaline). In addition, pH is 7 or more, alkaline,
It is acidified at pH <7. Note that a predetermined amount of mercury and a rare gas such as argon are sealed in the bulb 1.

In the fluorescent lamp having such a configuration, the fluorescent body 10 of the fluorescent body coating 6 formed on the inner surface of the bulb 1 includes:
The powder 20 having a charge tendency of +3.0 μC / g or more, for example, MgO, is attached to the reduced iron powder having a particle diameter of 44 to 74 μm. MgO has a strong property of adsorbing CO, CO ₂ and H ₂ O, but has a property of dissociating at 540 ° C. When mixed with a phosphor, the adsorbed CO or C
O ₂ and H ₂ O is phosphor coating base - is released in King step in the valve 1 becomes clean, after a subsequent sealing step, mainly MgO powder 20 remaining in the valve 1 The getter function is achieved by adsorbing impurities such as CO, CO ₂ and H ₂ O. This is because-
The OH group reacts with CO ₂ , causing Mg (OH) or Mg
It is presumed that a compound of CO ₃ was generated. For this reason, since the impurities do not remain in a floating state in the valve 1, the starting voltage Vs can be reduced, and starting is facilitated.

FIG. 3 shows the result of measuring the relationship between the charging tendency and the starting voltage Vs of a 40 W rapid-start fluorescent lamp using MgO powder. From this measurement result, the powder 20 having a charge tendency of +3.0 μC / g or more for the reduced iron powder having a particle diameter of 44 to 74 μm was obtained.
It has been found that the start voltage Vs can be reduced by using, and the start becomes easy.

FIG. 4 shows the results of measuring the relationship between the pH value and the starting voltage Vs of a 40 W rapid-start fluorescent lamp using MgO powder.
From this measurement result, it was found that when the powder 20 having a pH of 9 or more was used, the starting voltage Vs could be reduced, and starting was facilitated.

The specific surface area is 100 m ^2. / G or more, and if it is more than this, the surface area is large, so that the adsorption of impurities becomes good. If it is less than this, a sufficient effect cannot be expected. Next, a second embodiment shown in FIGS. 5 to 8 will be described.

The second embodiment shows an incandescent light bulb, for example, a light bulb for a traffic light, and 30 is an R-shaped bulb. The neck of one end of the valve 30 is closed by a stem 31, and a pair of lead wires 32, 32 is passed through the stem 31 in an airtight manner. A filament 33 is wrapped around the inner ends of these lead wires 32, 32, and the filament 33 is supported at its center by an anchor wire 34. A base 35 is attached to the neck of the bulb 30.

A white light diffusion film 36 is provided on the inner surface of the bulb 30.
The light diffusion film 36 is formed by attaching silica SiO ₂ powder 37 to the inner surface of the bulb 30 by means such as electrostatic coating.

In the case of this embodiment, the light diffusion film 36 includes, as shown in FIG. 5B, a powder 40 of a metal oxide such as MgO in addition to the silica powder 37 by 1 weight. %, And the powder 40 has a specific surface area of 100 m ^2. / G or more, whereby the metal oxide powder 40 has a charging tendency of +3.0 μC / g or more or a pH of 9 or more (alkaline).

In the case of such an incandescent lamp, the silica powder of the light diffusion film 36 formed on the inner surface of the bulb 30 contains
Since MgO powder having a charge tendency of +3.0 μC / g or more was attached to reduced iron powder having a particle diameter of 44 to 74 μm, the MgO powder 40 contained impurities remaining in the valve 1, particularly The getter function is exhibited by adsorbing H ₂ O. For this reason, since no H ₂ O remains in the bulb 1, no water cycle occurs and the filament has a long life.

FIG. 6 shows the relationship between the specific surface area of the MgO powder 40 and the lamp life when applied to a 60 W incandescent lamp. From the measurement results, the specific surface area of the powder 40 was 100 m ^2. / G or less, the effect was found to be low. This is thought to be because if the surface area is small, the contact area with the impurities is small, so that the adsorption performance is reduced.
Therefore, the specific surface area of the MgO powder 40 is 100 m ^2. / G or more is required.

FIG. 7 shows the result of measuring the relationship between the charging tendency of the metal oxide mixed in the silica powder and the lamp life. The charging tendency of the metal oxide is as shown in FIG.
Each oxide of Mg, Ca, Sr, Ba, and Zn has a positive charge tendency, and conversely, Si, Sn, Ti, Ge, T
Each oxide of a, Nb, V, and Mo has a negative charge tendency.

When each of these oxides was selected and the relationship between the charging tendency and the lamp life was measured, the charging tendency was -3.0 μC / g or less or +3.0 μC / g, as shown in FIG.
It has been found that it is better to be charged more than g. That is, the charging tendency exceeds −3.0 μC / g and +3.0 μC / g.
If it is less than C / g, the charging tendency is neutral and the moisture H
_It is considered that the force for taking in 2O is weak, and therefore, impurities remain in the valve.

On the other hand, when the charging tendency to the reduced iron powder is −3.0 μC / g or less, or +3.0 μC / g.
In the above case, since the charging tendency is biased, the moisture H ₂
It is considered that the performance of adsorbing O is improved, and the life is extended because H ₂ O does not remain in the valve. FIG. 8 shows the result of measuring the relationship between the pH value of the metal oxide and the lamp life.

By selecting metal oxides having different pH values,
When the relationship between the pH value and the lamp life was measured, it was found that better results were obtained when the pH value was 5 or less (acidic) or 9 or more (alkaline). When the pH value is 5 or less, or 9 or more, both the acidic and the alkaline properties are strong, so that the power of adsorbing water H ₂ O is strong, so that H ₂ O does not remain in the valve, and the life is extended. It is considered something.

As can be understood from the above description, it can be said that the fluorescent lamp and the incandescent lamp have a specific surface area of 100 m ^{2 in the} bulb. / G or more, and the powder has a charging tendency of +3.0 μC / g or more for reduced iron powder having a particle diameter of 44 to 74 μm, or 20% by weight.
If the pH value of the aqueous solution of is 9 or more (alkaline), a getter effect of adsorbing impurities in the valve is exhibited,
For fluorescent lamps, it is effective in improving the starting characteristics.
In the case of an incandescent lamp, it is effective for improving the life characteristics.

Further, in addition to the above range, the charging tendency is-
Even when the pH value in an aqueous solution of 3.0 μC / g or less or 20% by weight is 5 or less (acidic), a getter effect of adsorbing moisture in the bulb is exerted, which is effective for improving the life characteristics of an incandescent lamp. Note that the present invention is not limited to the above embodiment.

That is, the fluorescent lamp of the present invention is not limited to the rapid-start fluorescent lamp, but may be an ordinary fluorescent lamp, and the lamp may have various shapes such as a straight tube type, a ring type, and a compact bent type. It can be implemented in the case of.

[0036]

As described above, according to the first aspect of the present invention, powder having a charging tendency of +3.0 μC / g or more adsorbs CO, CO _2, H ₂ O, etc. in the valve and causes the powder to remain. Therefore, in the case of a fluorescent lamp, the starting voltage can be reduced, and in the case of an incandescent lamp, the life characteristics are improved.

[0037]

[Brief description of the drawings]

1A and 1B show a first embodiment of the present invention, wherein FIG. 1A is a cross-sectional view of a rapid-start fluorescent lamp, and FIG. 1B shows a state in which MgO powder is adhered to a fluorescent body. Pattern diagram.

FIG. 2 is a diagram showing the tendency of metal oxide powder to be charged.

FIG. 3 is a characteristic diagram showing a relationship between a charging tendency of a metal oxide powder and a starting voltage of a fluorescent lamp.

FIG. 4 is a characteristic diagram showing a relationship between a pH value of a metal oxide powder and a starting voltage of a fluorescent lamp.

5A and 5B show a second embodiment of the present invention, wherein FIG. 5A is a cross-sectional view of an incandescent lamp, and FIG. 5B is a schematic view showing a state in which MgO powder is mixed in a diffusion film.

FIG. 6 is a characteristic diagram showing a relationship between a specific surface area of a metal oxide powder and a lamp life.

FIG. 7 is a characteristic diagram showing a relationship between a charging tendency of a metal oxide powder and a lamp life.

FIG. 8 is a characteristic diagram showing a relationship between a pH value of a metal oxide powder and a lamp life.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Valve, 2 ... Stem, 3 ... Lead wire, 4 ... Electrode, 5
... Nesa film, 6 ... Phosphor coating, 10 ... Phosphor, 20 ...
MgO powder, 30 ... bulb, 33 ... filament, 36
... light diffusion film, 27 ... silica powder, 40 ... MgO powder.

Continued on the front page (72) Inventor Masaaki Tamaya 1 Toshiba-cho, Komukai, Koyuki-ku, Kawasaki City, Kanagawa Prefecture (56) References JP-A-56-138852 (JP, A) JP-A-1- 14862 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 61/26 H01J 61/35 H01K 1/32 H01K 1/54

Claims (4)

(57) [Claims] 1. The method according to claim 1, wherein substantially all inner surfaces of the valve have a particle diameter of 44.
+3.0 μC for the tendency to charge to ~ 74 μm reduced iron powder
/ G or more , and the specific surface area is 100 m ² / g or more.
A tube provided with a powder of fine particles . 2. The bulb according to claim 1, wherein the powder is attached to a surface of the phosphor powder of a phosphor film formed on substantially the entire inner surface of the bulb. 3. The powder according to claim 1, wherein the powder has a pH of 9 or more in a 20% by weight aqueous solution.
The tube as described. 4. The powder according to claim 1, wherein the powder is Mg, Ca, Sr, Ba,
The bulb according to any one of claims 1 to 3, comprising at least one oxide of Zn.