JPS6023946A - Low pressure mercury vapor discharge lamp - Google Patents

Abstract

PURPOSE:To obtain the captioned discharge lamp able to radiate the high photooutput even when the wall temperature of a transmissive airtight container is raised while causing no raised discharge starting voltage and having a short time prior to the stabilized photooutput by sealing the amalgam of one or both of tin and lead with the composite metal of bismouth and indium within a phototransmissive airtight container. CONSTITUTION:The amalgam of one or both of tin and lead with the composite metal of bismouth and indium is sealed within a phototransmissive airtight container. When the weight % of bismouth is more than 72wt% while assuming that the total weight of a composite metal constituting amalgam is 100wt% or the weight % of indium is less than 4wt%, the region, in which the solid phase and the liquid phase are coexisting, reaches a high temperature and accordingly, the temperature, at which the mercury capor pressure is stabilized, rises, while when the weight % of bismouth is smaller than 30wt% or the weight % of indium gets larger than 50wt%, the mercury vapor pressure at a low temperature is apt to drop. Further, an alloy mainly composed of bismouth, indium and mercury while including 15-57wt% of tin and 1-12wt% of lead shows the desirable properties.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a low-pressure mercury vapor discharge lamp, and makes it possible to improve the characteristics of a low-pressure mercury vapor discharge lamp such as a fluorescent lamp that places a high load on the wall of an airtight container. This invention relates to improvements in the structure of low-pressure mercury vapor discharge lamps.

[Technical background of the invention and its problems]

Low-pressure mercury vapor discharge lamps such as fluorescent lamps have a mercury vapor pressure of 6 x 10-3 to 7 x in their airtight container.
It is known that the efficiency with which the supplied electrical energy is converted into mercury's 253.7 nm ultraviolet radiation is highest at relatively low discharge currents of 10-3 times 1-1 g. Since the radiation in the ultraviolet region of 253.7 nm has a high phosphor excitation efficiency, the above 6X'l0-3 to 7X1
Preferably, the mercury vapor pressure is maintained at 0-3% HH.

At this time, the temperature of the wall of the airtight container was approximately 40°C.

However, in recent years, low-pressure mercury vapor discharge lamps such as fluorescent lamps have become increasingly thin in tube diameter and have a high load on the wall of the airtight container, resulting in high temperatures on the wall of the airtight container.

Some temperatures exceed 100°C. In this way, when the wall temperature of the airtight container becomes high, the mercury vapor pressure inside the airtight container increases to 6x 1o.
-3'In Hg is significantly higher than that of Hg, and the emitted ultraviolet radiation, mainly at 253.7 nm, is self-absorbed by mercury, reducing the conversion efficiency of supplied electrical energy to ultraviolet radiation. There was a problem in which the light output decreased.As a countermeasure to this problem, it is known to seal amalgam in an airtight container, for example, with mercury and indium.

Tokuko Showa has developed a fluorescent double lamp using an amalgam made of one metal selected from lithium, aluminum, zinc, soot, lead, and bismuth, an amalgam of mercury, bismuth, and lead, or an amalgam of mercury, bismuth, lead, and soot. 54-3321.
Publication No. 5, 1% Publication No. 1982-38582, etc.

However, in fluorescent lamps using the amalgam described above, the mercury vapor pressure is too low at low temperatures, so the discharge starting voltage is high, the time it takes for the light output to stabilize at a predetermined value is long, and the stable luminous flux value is also high. There was a problem that the amount was low.

[Purpose of the invention]

The present invention has been made to address the above-mentioned problems in the background art, and it is possible to emit a high light output equivalent to that at room temperature even if the wall temperature of a translucent airtight container is high (even if the wall temperature is high), and the discharge starting voltage is high. The object of the present invention is to provide a low-pressure mercury vapor discharge lamp, such as a fluorescent lamp, which has favorable characteristics, such as a short time required for the light output to stabilize, and a low-pressure mercury vapor discharge lamp.

[Summary of the invention]

The present invention is a low-pressure mercury vapor discharge lamp characterized in that a multi-metal amalgam of one or both of tin and lead, bismuth and indium is sealed in a light-transmitting airtight container.

[Embodiments of the invention]

The details of the present invention will be explained with reference to examples.

The present inventors manufactured an alloy using multiple metals such as bismuth, indium, tin, and lead, and for the alloy noamalgam, the weight of each of the multiple metals constituting the alloy and the total weight of the alloy of the multiple metals ( Various amalgams were manufactured by changing the weight % (100N amount %) within the range shown in Table 1 below.

The amount of mercury was 4 to 25% by weight based on the total weight of the amalgam.

Table 1: The present inventors sealed the various types of amalgams described above in a light-transmitting airtight container to produce a fluorescent lamp 2, which is an example of a low-pressure mercury vapor discharge lamp.
00V40W was manufactured and tested. In the test, the wall temperature ('O) of the translucent airtight container was varied and the mercury vapor pressure (mm Hg) inside the airtight container at that time was measured.

As a result, it was found that among the amalgams having the compositions shown in Table 1 above, the fluorescent lamps of the present invention filled with types (5), (B), and
In the figure, the horizontal axis represents the temperature (°C) of the wall of the translucent airtight container, and the vertical axis represents the mercury vapor pressure (Hg) of the amalgam inside the translucent airtight container.
) is a characteristic curve diagram.

Curve (a) is the type in Table 1 (5) Curve 1 (b) is the type in the same table (characteristics of q, and Curve 2 (C) is type p in Table 1)
The second curve (d) also shows the type (characteristics of odor. Song IJ).
(e) shows the characteristics of a fluorescent lamp in which only mercury is sealed in a translucent airtight container.

As is clear from FIG.
to 130'O when 6 X 10-3 to 7
X I Q- maintains a stable mercury vapor pressure of 3 mrnHg, and curve 5 (C) s (d) 1 (e) does not maintain the above mercury vapor pressure in the above temperature range, therefore, in the above temperature range Electric energy to mercury 253.71
It can be seen that the efficiency of converting m to ultraviolet light is low and is not equal to jJ. Note that curve (a) also applies to type (B) in Table 1.
And the same characteristics as (b) were obtained.

Figure 2 is a characteristic curve diagram showing the stability characteristics of the luminous flux after two lightings, with the horizontal axis representing the lighting time (minutes) of the fluorescent lamp and the vertical axis representing the specific luminous flux value (%). Characteristics of fluorescent lamps filled with amalgam of types (5), (B), and (C) shown in Table 1, curve (c) are characteristics of fluorescent lamps filled with amalgam of types (Q, (yen) shown in Table 1. It shows.

Curve H is a characteristic curve of a conventional fluorescent lamp filled only with mercury. As is clear from Figure 2 of the coffin, Table 1 (5),
The amalgam-filled fluorescent lamps shown in (B) and (C) reach the maximum luminous flux value 5 minutes after lighting, as shown by curve (C). As shown in the figure, the luminous flux value decreases after lighting and reaches 6 after about 50 minutes.
It does not become stable at around 5%, and exhibits extremely good characteristics. The curve ■ is the component metal of the alloy that constitutes the amalgam types (5), (B), and (C) in Table 1 above, and the weight of the types (5), , (B), and (C) in Table 1 above. For fluorescent lamps filled with amalgam with a composition outside the % range, it takes about 40 minutes for the luminous flux to stabilize, but after 40 minutes it takes the same amount of time as the curve). reaches a luminous flux value of Table 1 (5) above, fB
), (C'), i.e., the curve shown in FIG. 2) and the fluorescent lamp having the characteristics within the curve belong to the present invention.

The above-mentioned fluorescent lamp of the present invention has a high discharge starting voltage (there were no problems with excessive discharge starting voltage). This is a characteristic curve diagram of the case where the mercury content of the amalgam is varied and sealed in a fluorescent lamp, and the respective curves and the mercury content of the amalgam are shown in Table 2 below.

This test is performed as an amalgam sealed in a fluorescent lamp.
For example, bismuth uses a multi-metal alloy amalgam of bismuth, indium, and soot.

The total weight of the multi-metal alloy of indium and tin is 1
Bismuth 62% by weight when closed.

Amalgams were prepared with varying weight percentages of mercury, including 19% by weight indium and 19% by weight tin.

Table 2' From Figure 3, a fluorescent lamp whose luminous flux can maintain at least 95% of the maximum value when the temperature of the translucent airtight container is 60 to 130°C (range indicated by T in Figure 3). The mercury content of the amalgams was found to be between 4 and 25% by weight of curves n, m, iv. Furthermore, even if the combination of multiple metals other than mercury is different from the above experimental example, the mercury content of the amalgam will be as shown in Figure 3 above if it is a combination of one or both of tin and lead with bismuth and indium. Curves n, m, r shown
It showed the same result as v.

In the above experimental example, the multiple metals constituting the amalgam are alloys, and the case of an amalgam of the above alloys was described.
The present inventors have confirmed through experiments that the above results do not change even when each of the plurality of metals is a single metal and an amalgam is composed of the plurality of metals and mercury.

The present invention was applied not only to the above-mentioned fluorescent lamps but also to low-pressure mercury vapor discharge lamps in general, and the desired effects were obtained.

According to the experiments conducted by the present inventors, the metals constituting the amalgam used in the low-pressure mercury vapor discharge lamp of the present invention are mainly composed of bismuth and indium, and the weight percent of bismuth O is
The total weight of multiple metals that make up the amalgam is 100M.
If the amount of indium is more than 72% by weight or less than 4% by weight, the region where the same phase and liquid phase of the above alloy coexist becomes high temperature, and therefore the mercury vapor pressure is stabilized. The higher the temperature, the more the weight% of bismuth
is less than 30% by weight or the weight% of indium
When the amount exceeds 50% by weight, the mercury vapor pressure at low temperatures tends to decrease. In addition, the weight of soot is 15 to 57% by weight, or the weight of lead is 5 to 40% by weight.
The region in which the mercury vapor pressure is stable becomes narrower as it deviates from the range. Further, the above-mentioned alloy mainly composed of bismuth, indium, and mercury, in which 15 to 57 wt.

〔Effect of the invention〕

The present invention relates to a low-pressure mercury vapor discharge lamp such as a fluorescent lamp, characterized in that a multi-metal amalgam of one or both of tin and lead, bismuth and indium is sealed in a translucent airtight container. .

The load on the wall of the translucent airtight container is the tube diameter strain of the translucent airtight container I.
Even if it becomes high, the desired 6 X l O-3
It is possible to maintain a mercury vapor pressure of about 7 to 10-3 Hg, and therefore it is possible to maintain a high conversion efficiency of electrical energy to ultraviolet radiation, and the stabilization time of optical output is short and stable. This has the effect of providing a low-pressure mercury vapor discharge lamp such as a fluorescent lamp that can emit high light output.

[Brief explanation of drawings]

In Figure 1, the horizontal axis shows the temperature (
°C) and the vertical axis is the mercury vapor pressure (mWLHg, ) of the amalgam in the translucent airtight container,
Figure 2 shows the lighting time (minutes) of the fluorescent lamp on the horizontal axis, the specific luminous flux value (%) on the vertical axis, and the luminous flux (%) after lighting.The mercury content in the fluorescent lamp 2 was changed. FIG. Agent: Patent attorney Kensuke Chika (and 1 other person)

Claims (6)

[Claims] (1) A light-transmitting airtight container, electrodes sealed to both ends of the light-transmitting airtight container, and an easily dischargeable electric body sealed in the light-transmitting airtight container. A low-pressure mercury vapor discharge lamp characterized in that a multi-metal amalgam of at least one of tin and lead, bismuth, and indium is sealed in the translucent airtight container. (2) Amalgam sealed in a translucent airtight container. The low-pressure mercury vapor discharge lamp according to claim 1, characterized in that it is an amalgam of an alloy of at least one of tin and lead, bismuth, and indium. (3) Claims characterized in that the amalgam sealed in the translucent airtight container contains mercury in an amount of 4 to 25 weight i:% when the weight of the amalgam is 100 weight %. The low-pressure mercury vapor discharge lamp according to paragraphs 1 and 2. (4) The multiple metals constituting the amalgam sealed in the translucent airtight container are 30 to 72% by weight of bismuth and 4 to 50% by weight of indium when the weight of the multiple metals is 100% by weight. A low-pressure mercury vapor discharge lamp according to any one of claims 1 to 3, characterized in that the lamp contains: (5) The plurality of metals constituting the amalgam sealed in the translucent airtight container contain 15 to 57% by weight of soot and 1 to 12% by weight when the weight of the plurality of metals is 100% by weight.
5. The low-pressure mercury vapor discharge lamp according to claim 4, characterized in that it contains a heavy amount of lead. (6) The plurality of metals constituting the amalgam sealed in the translucent airtight container contain 15 to 57% by weight of soot when the weight of the plurality of metals is 100% by weight. The low-pressure mercury vapor discharge lamp according to claim 4, characterized in that it contains 5 to 40% by weight of lead.