JPS5818743B2 - metal vapor discharge lamp - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an ultraviolet metal vapor discharge lamp used as a light source for photochemical reactions and paint drying.

Conventionally, ultraviolet high-pressure mercury lamps have been mainly used as light sources for photochemical reactions and paint drying.

However, as shown in Figure 3, the light emitted from a high-pressure mercury lamp consists of a large number of bright line spectra, and each spectrum is dispersed over a fairly wide wavelength range. May not be effective as a light source for reactions or paint drying.

For example, if a high-pressure mercury lamp is used as a light source for photochemical reactions or paint drying in the effective wavelength range of 280 to 420 nm,
As shown in the figure, 302 nm 313 nm, 3
The 65 nm emission line spectrum contributes to the reaction, but the 25 nm
Strong emission line spectra such as 4 nm, 436 nm, 546 nm, and 578 nm do not contribute to the reaction and have the disadvantage that most of the light energy is wasted.

Most of the light energy of the present invention is concentrated in a specific wavelength range, especially in the wavelength range of 280 to 420 nm, and therefore, the ultraviolet light source is extremely effective as a light source for photochemical reactions and paint drying in which this range is the effective wavelength range. The object of the present invention is to provide a metal vapor discharge lamp.

. The present invention will be explained below with reference to the drawings.

In Fig. 1, 1 is an arc tube made of a heat-resistant transparent material such as quartz glass, 2a and 2b are electrodes sealed at both ends of the arc tube 1, 3a and 3b are metal foils, and 4a and 4b are external leads. Show the line.

The interior of the arc tube 1 is filled with a sufficient amount of mercury to maintain arc discharge, appropriate amounts of rare gas and halogen, as well as iron and tin.

The reason why tin is sealed together with iron in the arc tube is as follows.

In other words, tin has conventionally been known as a filler material for high-efficiency lamps for general lighting that have a strong continuous spectrum in the visible light region, but according to Kame Invention, reducing the amount of tin filler will cause problems such as photochemical reactions and paints. Strong emission line spectrum that is effective as a light source for drying, such as 280 nm, 286 nm, 3
01 nm, 303 nm.

318 nm and 326 nm were observed, but not in general lighting lamps.

This is because it was confirmed that the light energy increases from 280 to 330 nm.

In order to obtain the above effect, the amount of halogen that should be sealed in the waste light tube should be 1.0X per cIft of internal volume of the light tube.
Desirably 10-5 to 1.0 x 10' gram atoms.

If the amount exceeds this range, the starting voltage, restriking voltage, and lamp voltage of the discharge lamp will increase, resulting in poor electrical characteristics.On the other hand, if it is less than the above range, sufficient ultraviolet output will not be obtained.

This halogen may be encapsulated in the form of a single substance, but encapsulation work becomes easier if it is encapsulated as a compound with mercury, iron, and tin.

Further, the total amount of iron and tin to be sealed in the arc tube is desirably in the range of 1/2 to 3 in atomic ratio to the halogen.

If the total amount of iron and tin is less than this range, not only will sufficient ultraviolet output not be obtained, but free halogen will be generated and the electrical characteristics of the discharge lamp will deteriorate; It adheres to the inside of the arc tube and causes dimming.

Furthermore, the atomic ratio of tin to be filled in the arc tube must be in the range of 1/20 to 3 times that of iron.

If the tin content is less than the above range, the light energy will be 330-42
This is because light energy is concentrated in the wavelength range of 0 nm, and conversely, if it exceeds the above range, it is concentrated in the wavelength range of 280 to 330 nm, making it impossible to obtain an average light energy over the entire wavelength range of 280 to 420 nm. be.

Table 1 shows experimental results showing the basis for limiting the atomic ratio of iron and tin to the above range.

The lamp used in the experiment had an inner diameter of 20 mm and a distance between electrodes of 25 mm.
In an arc tube with an internal volume of 84.8 Ce, mercury to form an arc, an appropriate amount of argon gas, and iodine in a chemical equivalent equal to the total amount of iron and tin, as shown in Table 1. The amount of iron and tin enclosed was selected as follows.

As is clear from this table, the atomic ratio of tin to iron is 1.
/20 to 3, emission line spectra of iron and tin are observed, and ultraviolet metal vapor is extremely effective for photochemical reactions and paint drying, with energy concentrated in a specific wavelength range of 280 to 420 nm. You can get a discharge lamp.

Note that what is characteristic in Table 1 is that when the amount of tin is more than 6X10-7 gram atoms per 1 d of internal volume of the arc tube, molecular luminescence is observed in general lighting lamps; In the lamp of the present invention, a tin emission line spectrum is observed.

Finally, to explain the embodiment of the present invention, the inner diameter is 20
Ryu, 150 drops of mercury, 5.8 drops of mercury iodide, 1.0% iron, 1.5In9 argon gas, 15mmH of argon gas, in an arc tube with a distance between electrodes of 250mm and an internal volume of 84.8CC! When a 2 kW metal vapor discharge lamp containing 7 was lit, its spectral energy distribution was as shown in FIG.

As is clear from this figure, according to the present invention, 280 to 4
It is possible to obtain an ultraviolet metal vapor discharge lamp in which most of the light energy is concentrated in the 20 nm wavelength range, which is extremely effective for photochemical reactions and paint drying.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an ultraviolet metal vapor discharge lamp according to the present invention, FIG. 2 is a spectral energy distribution diagram of the discharge lamp, and FIG. 3 is a spectral energy distribution diagram of a conventional high-pressure mercury lamp. In FIG. 1, 1... arc tube, 2a, 2b,
...Electrode, 3a, 3b...Metal foil, 4a
, 4b...External lead wire.

Claims (1)

[Claims] 1 Inside the arc tube equipped with electrodes, halogen, along with a sufficient amount of mercury and an appropriate amount of rare gas to maintain arc discharge.
Enclose iron and tin, and increase the amount of halogen to the inner volume of the arc tube 1
1.0X10-5 to 1.0X10-8 gram atoms per d, and the total amount of iron and tin is 1 in atomic ratio to halogen.
/2 to 3, and the amount of tin to iron is 1/2 in atomic ratio.
0 to 3, and has light energy concentrated in the ultraviolet region of 280 to 420 nm.