JP2008226806A - Light source for uv irradiation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source for UV irradiation which can prevent a UV irradiation lamp from becoming heated up to a high temperature. <P>SOLUTION: An outer surface of an outer tube 22 is coated by a metal oxide film 4 containing metal oxide composed of one ore more sorts out of TiO<SB>2</SB>, CeO<SB>2</SB>, ZnO<SB>2</SB>, SnO<SB>2</SB>, ZrO<SB>2</SB>. By coating the metal oxide film 4 on the outer tube 22, an area of the metal oxide film 4 becomes larger and a cooling effect of the metal oxide film 4 by a cooling liquid is raised, and, as a result, the UV irradiation lamp can be prevented from becoming heated up to a high temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light source for ultraviolet irradiation in which an ultraviolet irradiation lamp and a heat ray cut filter are held in a double-tube water-cooled jacket.

  The light source for photochemical reaction is used for hardening of resin, for example. The effective wavelength range for resin curing is generally considered to be 300 to 400 nm or 300 to 430 nm. On the other hand, light in other wavelength ranges is not only effective for curing the resin, but may cause a temperature rise and deterioration of the resin. Therefore, it is desirable to irradiate only an ultraviolet ray having a desired wavelength component to the irradiation target.

As described in Patent Document 1, a conventional ultraviolet irradiation light source (hereinafter referred to as “conventional light source”) includes an ultraviolet irradiation lamp and an ultraviolet selective wavelength transmission filter in a double-tube water-cooling jacket 2. constitutes at _T i _{O 2, C} e2 _O quartz glass tube is deposited a metal oxide film such as ₃ to absorb wavelengths below ingredients 300nm on the inner surface of the inner tube.

In the conventional light source, light is emitted from the ultraviolet irradiation lamp inside the inner tube, and a wavelength component of 300 nm or less is absorbed by the metal oxide film. Thereby, the wavelength component of 300 nm or less does not reach the irradiation target, and thus the temperature rise and deterioration of the resin as the irradiation target can be prevented.
Japanese Patent Laid-Open No. 06-267509

  In the conventional light source, a coolant such as water circulates in the water cooling jacket.

  The power consumption of the ultraviolet irradiation lamp is as large as several kW, and the ultraviolet irradiation lamp is thus cooled by the cooling water in order to prevent the ultraviolet irradiation lamp from being damaged by its own temperature rise. Further, the output characteristics of the ultraviolet irradiation lamp can be stabilized by cooling.

  However, in the conventional light source, since the wavelength component of 300 nm or less is absorbed by the metal oxide film, the metal oxide film is deposited on the inner surface of the inner tube. There is a tendency for heat to accumulate inside the space. Therefore, there is a risk that the ultraviolet irradiation lamp becomes hot and the ultraviolet irradiation lamp is damaged. Moreover, there is a possibility that the output characteristics of the ultraviolet rays in the ultraviolet irradiation lamp become unstable due to the high temperature.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an ultraviolet irradiation light source that prevents the ultraviolet irradiation lamp from being heated to a high temperature.

  In order to solve the above-described problems, a light source for ultraviolet irradiation according to the present invention is a double tube including an ultraviolet irradiation lamp, an inner tube containing the ultraviolet irradiation lamp, and an outer tube provided outside the inner tube. A water-cooling jacket having a shape, and means for absorbing a wavelength component of 300 nm or less emitted from the ultraviolet irradiation lamp, which is provided on the inner surface of the outer tube or the outer surface of the water-cooling jacket or the outer surface of the inner tube. Characterized by

  According to the light source for ultraviolet irradiation according to the present invention, a means for absorbing a wavelength component of 300 nm or less is provided on the inner surface or the outer surface of the double tube water-cooling jacket or the outer surface of the inner tube. The cooling effect by the coolant circulating between the outer tubes is enhanced, and thus the ultraviolet irradiation lamp can be prevented from being heated to a high temperature.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic side view of a light source for ultraviolet irradiation according to the first embodiment (referred to as “main light source” in the description of the first embodiment).

  The light source includes an ultraviolet irradiation lamp 1, a water cooling jacket 2, and a heat ray cut filter 3. The ultraviolet irradiation lamp 1 has a pair of electrodes sealed at both ends of a straight tubular quartz glass arc tube, and a metal halogen that can emit light effectively in the ultraviolet region such as rare gas, mercury, Fe, Sn, Co, and Mg. One or more chemical compounds are enclosed. The water cooling jacket 2 is made of a transparent material such as cylindrical quartz glass, and includes an inner tube 21 and an outer tube 22 provided outside thereof, and has a double tube structure. The ultraviolet irradiation lamp 1 is included in the inner tube 21.

  A coolant such as water is circulated from the outside through connection pipes 23a and 23b provided at the outer peripheral end of the jacket. The heat ray cut filter 3 is made of a tubular low-softening point glass, and transmits light having a wavelength range of 430 nm or less, which is effective for curing the resin, and absorbs visible light having a wavelength of 430 nm or more. In order to minimize the temperature rise due to heat from the lamp, it is disposed between the inner tube 21 and the outer tube 22 and immersed in the coolant.

A metal oxide film 4 containing a metal oxide is deposited on the outer surface of the outer tube 22. The metal _{oxide, T i O 2, C e} O 2, Z n O 2, S n O 2, composed of at least one kind of Z r _{O 2.}

  The metal oxide film 4 is component-adjusted so as to absorb a wavelength component of 300 nm or less of the light emitted from the ultraviolet irradiation lamp 1.

  And when light is radiated | emitted from the ultraviolet irradiation lamp 1, the heat ray cut filter 3 will absorb a wavelength component more than 430 nm first. Next, the metal oxide film 4 deposited on the outer surface of the outer tube 22 absorbs a wavelength component of 300 nm or less. Therefore, ultraviolet rays having a wavelength range of 300 to 430 nm effective for curing the resin are transmitted through the water-cooling jacket 2 and irradiated to an irradiation target such as a resin.

  FIG. 2 is a diagram comparing the temperature of the tube wall of the ultraviolet irradiation lamp 1 (referred to as the arc tube tube temperature) between this light source and a conventional light source.

  As is apparent from FIG. 2, in this light source, the metal tube 4 is deposited on the outer surface of the outer tube 22, so that the temperature of the arc tube tube wall is made lower than that of the conventional light source. Can do.

  This is considered to be due to the fact that the metal oxide film 4 is deposited on the outer tube 22, thereby increasing the area of the metal oxide film 4 and increasing the cooling effect of the metal oxide film 4 by the cooling liquid. Can do.

  Therefore, according to the present light source, it is possible to prevent the ultraviolet irradiation lamp 1 from being heated to a high temperature, thereby preventing the ultraviolet irradiation lamp 1 from being damaged and stabilizing the output characteristics of the ultraviolet light in the ultraviolet irradiation lamp 1.

[Second Embodiment]
FIG. 3 is a schematic side view of a light source for ultraviolet irradiation according to the second embodiment (referred to as “main light source” in the description of the second embodiment).

  Since this light source includes the same components as those of the light source for ultraviolet irradiation according to the first embodiment, the same reference numerals are given to the components to simplify the description, and differences will be mainly described.

  The light source includes an ultraviolet irradiation lamp 1, a water cooling jacket 2, and a heat ray cut filter 3.

A metal oxide film 4 a containing a metal oxide is deposited on the outer surface of the inner tube 21. Further, a metal oxide film 4 a containing the same metal oxide is deposited on the inner surface of the outer tube 22. The metal _{oxide, T i O 2, C e} O 2, Z n O 2, S n O 2, composed of at least one kind of Z r _{O 2.}

  Both the metal oxide films 4a and 4b are adjusted so as to absorb a wavelength component of 300 nm or less of the light emitted from the ultraviolet irradiation lamp 1.

  In addition, the inner metal oxide film 4a is transparent to the wavelength component so that the wavelength component is absorbed by the outer metal oxide film 4b.

  When light is emitted from the ultraviolet irradiation lamp 1, first, the metal oxide film 4a deposited on the outer surface of the inner tube 21 absorbs part of the wavelength component of 300 nm or less. Next, the heat ray cut filter 3 absorbs a wavelength component of 430 nm or more. Next, the metal oxide film 4b deposited on the inner surface of the outer tube 22 absorbs a wavelength component of 300 nm or less that has passed through the metal oxide film 4a. Therefore, ultraviolet rays having a wavelength range of 300 to 430 nm effective for curing the resin are transmitted through the water-cooling jacket 2 and irradiated to an irradiation target such as a resin.

  Although not shown in the drawings, in this light source, the metal tube is deposited on the outer surface of the inner tube 21 and the inner surface of the outer tube 22, so that the arc tube tube wall temperature becomes lower than the arc tube tube wall temperature of the conventional light source. The experimental results were obtained.

  This is because the metal oxide film was deposited on the outer surface of the inner tube 21 and the inner surface of the outer tube 22, thereby increasing the area of the metal oxide film and increasing the cooling effect of the metal oxide film by the coolant. It can be considered that.

  Therefore, according to the present light source, it is possible to prevent the ultraviolet irradiation lamp 1 from being heated to a high temperature, thereby preventing the ultraviolet irradiation lamp 1 from being damaged and stabilizing the output characteristics of the ultraviolet light in the ultraviolet irradiation lamp 1.

[Third Embodiment]
FIG. 4 is a schematic side view of a light source for ultraviolet irradiation (referred to as “main light source” in the description of the third embodiment) according to the third embodiment.

  Since the present light source includes the same components as those of the light source for ultraviolet irradiation according to the second embodiment, the same reference numerals are given to the components to simplify the description, and differences will be mainly described.

  The light source includes an ultraviolet irradiation lamp 1 and a water cooling jacket 2, but does not include a heat ray cut filter 3.

  A metal oxide film 4 c containing a metal oxide is deposited on the outer surface of the inner tube 21. A metal oxide film 4d containing the same metal oxide is deposited on the inner surface of the outer tube 22.

Metal oxide film 4c, 4d are both at least _T i _O 2 to absorb 300nm or less wavelength components of the light emitted from the ultraviolet irradiation lamp _{1, C e O 2, Z} n O 2, S n Containing at least one of O ₂ and Z _r O ₂ and including at least one of a phosphate added with nickel and a phosphate added with cobalt so as to absorb a wavelength component of 400 nm or longer. Consists of component adjustments.

  Moreover, the inner metal oxide film 4c is transparent to the wavelength component so that the wavelength component is also absorbed by the outer metal oxide film 4d.

  When light is emitted from the ultraviolet irradiation lamp 1, first, the metal oxide film 4c deposited on the outer surface of the inner tube 21 absorbs part of the wavelength component of 300 nm or less and part of the wavelength component of 400 nm or more. To do. Next, the metal oxide film 4d deposited on the inner surface of the outer tube 22 absorbs the wavelength component of 300 nm or less and the wavelength component of 400 nm or more that have passed through the metal oxide film 4c. Therefore, ultraviolet rays having a wavelength range of 300 to 400 nm effective for curing the resin are transmitted through the water-cooling jacket 2 and irradiated to an irradiation target such as a resin.

  Although not shown, in this light source, the metal tube is deposited on the outer surface of the inner tube 21 and the inner surface of the outer tube 22, so that the arc tube wall temperature becomes lower than the arc tube tube temperature of the conventional light source. The experimental results were obtained. The reason can be considered to be the same as in the second embodiment.

  Therefore, according to the present light source, it is possible to prevent the ultraviolet irradiation lamp 1 from being heated to a high temperature, thereby preventing the ultraviolet irradiation lamp 1 from being damaged and stabilizing the output characteristics of the ultraviolet light in the ultraviolet irradiation lamp 1.

  In view of the fact that the cooling effect of the metal oxide film by the cooling liquid is increased, the metal oxide film used in the above embodiment may be provided only on the inner surface of the outer tube.

It is a schematic side view of the light source for ultraviolet irradiation which concerns on 1st Embodiment. It is the figure which compared the arc tube wall temperature with this light source and the conventional light source. It is a schematic side view of the light source for ultraviolet irradiation which concerns on 2nd Embodiment. It is a schematic side view of the light source for ultraviolet irradiation which concerns on 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ultraviolet irradiation lamp 2 ... Water cooling jacket 21 ... Inner pipe | tube of the water cooling jacket 2 22 ... Outer pipe | tube 23a, 23b ... Connection pipe | tube 3 ... Heat ray cut filter 4, 4a, 4b, 4c, 4d ... Metal oxide film

Claims (3)

An ultraviolet irradiation lamp,
A double-tubular water-cooling jacket comprising an inner tube containing the ultraviolet irradiation lamp and an outer tube provided outside the inner tube;
Means for absorbing a wavelength component of 300 nm or less emitted from the ultraviolet irradiation lamp, provided on the inner surface or outer surface of the outer tube or the outer surface of the inner tube of the water-cooling jacket;
An ultraviolet light source characterized by comprising:   2. The ultraviolet light source according to claim 1, wherein the means for absorbing a wavelength component of 300 nm or less is a metal oxide film containing a metal oxide. The metal _oxide, ultraviolet _{T i O 2, C e O} 2, Z n O 2, S n O 2, according to claim 2, characterized in that it is composed of at least one kind of Z r _{O 2} Light source for irradiation.

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