JP2008282748A - Metal halide lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal halide lamp that can achieve longevity by encapsulating metal halides or the like. <P>SOLUTION: A metal halide lamp 52 in which noble gas, mercury, metal halide is encapsulated as discharge medium in a gas-tight arc tube 520, and discharge electrodes 521, 522 are provided at both ends in tube axis direction of a lamp container, wherein a metal in metal halides is any transition metal of which electronegativity is 1.5<N<2.0 except for iron element. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a metal halide lamp.

  In general, an ultraviolet light-emitting metal halide lamp having a high light emission intensity in the vicinity of 350 to 380 nm is effective for curing an ultraviolet curable paint and for a photoreaction to a functional polymer film having a high market use in recent years.

  However, light in an emission wavelength region of 340 nm or less is known to cause deterioration of the functional material, and is used while suppressing these short wavelengths.

  In order to satisfy such a requirement, as described in Japanese Patent Laid-Open No. 03-250549 (Patent Document 1), metal thallium or thallium halide is sealed together with iron and mercury in an airtight container. There is known an ultraviolet irradiation lamp that suppresses ultraviolet rays having a short wavelength of 340 nm or less and has high emission intensity in the vicinity of 365 nm.

However, in the case of such a conventional mercury ultraviolet lamp, the iron element contained in the discharge medium reacts with quartz, which is the material of the arc tube, or forms tungsten and amalgam, which is the material of the discharge electrode. There was a problem that the lamp life could not be expected.
Japanese Patent Laid-Open No. 03-250549

  The present invention has been made in view of the above technical problem, and an object of the present invention is to provide a metal halide lamp capable of extending the life.

  The present invention is a metal halide lamp in which a rare gas, mercury, and a metal halide are sealed as a discharge medium in an airtight arc tube, and discharge electrodes are installed at both ends in the tube axis direction of the lamp vessel. The metal in is characterized by being any transition metal having an electronegativity N of 1.5 <N <2.0, excluding iron elements.

  According to the metal halide lamp of the present invention, the metal in the metal halide in the discharge medium is any transition metal having an electronegativity N of 1.5 <N <2.0 except for iron elements. During operation, the arc tube material quartz and metal halide do not react, and the electrode material tungsten and metal halide do not form amalgam, resulting in a longer lamp life. Can be achieved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1, a metal halide lamp 52 according to an embodiment of the present invention includes electrodes 521 and 522 made of tungsten (W) or the like disposed inside a quartz luminous tube 520 having ultraviolet transparency. Sockets 523 and 524 are provided respectively. One specification of the ultraviolet discharge lamp 52 of this embodiment is, for example, an outer tube diameter of 27.5 mm, a wall thickness of 1.5 mm, a light emission length L of 1000 mm, a lamp voltage of 1100 V, and a lamp current value of 11.0 A.

  The arc tube 520 is filled with a rare gas such as argon (Ar) gas, mercury, and thallium iodide (TlI) as a metal halide. When thallium iodide is employed as the metal halide, as shown in FIG. 2, it has a large emission peak in the vicinity of wavelengths 352 nm, 365 nm, and 378 nm, particularly in the vicinity of wavelengths 352 nm and 378 nm. This light emission characteristic has the effect of reducing the emission intensity of mercury, and therefore, it is possible to emit ultraviolet light that suppresses mercury emission at 313 nm and relatively increases emission in the wavelength region of 340 to 400 nm. Therefore, when the metal halide lamp 52 of the present embodiment is used in a process of forming an alignment film on a glass plate by irradiating ultraviolet rays in the production of a liquid crystal panel to polymerize an ultraviolet reactive material, a wavelength that greatly affects the characteristics of the liquid crystal panel. Irradiation of ultraviolet rays having a region of 340 nm or less can be reduced.

  In addition, it replaces with thallium iodide as a metal halide, and can also employ | adopt thallium bromide. In addition to the thallium described above, for example, Co, Ni, and In can be used as a transition metal having an electronegativity N of 1.5 <N <2.0, excluding iron elements, which can be used for metal halides.

The front view of the metal halide lamp of one embodiment of this invention. Graph of spectral characteristics of the metal halide lamp.

Explanation of symbols

52 ... Metal halide lamp 520 ... Arc tube 521, 522 ... Electrode 523, 524 ... Socket

Claims (1)

A metal halide lamp in which a rare gas, mercury and a metal halide are sealed as a discharge medium in an airtight arc tube, and discharge electrodes are installed at both ends in the tube axis direction of the lamp vessel,
The metal halide lamp according to claim 1, wherein the metal in the metal halide is any transition metal having an electronegativity N of 1.5 <N <2.0, excluding iron elements.

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