JPS599214B2 - Indirect ultraviolet irradiation treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing heat from an ultraviolet irradiation device having a mercury lamp from being applied to an irradiated object.

In recent years, the curing treatment of ultraviolet ray curable inks, paints, etc. using an ultraviolet irradiation device using a mercury lamp has come into practical use.

The mercury lamp used in this device usually has an output of 30 to 160 Watt/crfL per unit length of the lamp, and its ultraviolet generation efficiency is about 15 to 30 inches, with the rest being generated by heat, visible light, etc. Become.

In addition, the irradiation time for the object to be processed using these devices is usually in seconds, but in cases where longer irradiation time is required or when the object to be processed is something that is easily affected by heat, such as paper, plastic, or film, The heat received by the aforementioned lamps is a problem.

Generally, in such cases, the object to be treated is air-cooled during irradiation, or a mercury lamp is installed inside a double glass tube and a water-cooled lamp is used in which water flows into the space inside the tube.

However, in the former case, cooling may be insufficient in some cases, and in the latter case, there are problems such as loss of transmitted energy due to double glazing and increased costs due to the complexity of the equipment.

The present invention aims to provide an indirect ultraviolet irradiation treatment apparatus that is simpler than the above-mentioned systems and has an excellent effect in blocking heat rays.

The present invention provides an apparatus for irradiating an irradiated object using a mercury lamp as an irradiation source, in which an ultraviolet-transmitting transparent plate is provided between the irradiated object and the irradiation source, and a refrigerant liquid that forms a film flow along the transparent plate is provided. A cooling device consisting of the following is interposed.

In general, there are examples of windows using heat-absorbing glass to block heat rays from sunlight, etc., but the present invention is equivalent to water-cooling these glasses. An example will be explained based on the figures.

In FIG. 1, a conveyor 3 is provided below an irradiation device having a mercury lamp 1 and a reflector 2. As a cooling device, the horizontal bottom is formed of an ultraviolet-transparent transparent plate 4, and a refrigerant liquid inlet 5 is provided on one side. , shows an example using a coolant tank A having a coolant liquid outlet 6 on the other side.

In the figure, 7 is the surrounding wall of the liquid tank, and 8 is the object to be irradiated. In such a device, a refrigerant liquid such as water enters the cooling liquid tank through the inlet 5, transfers while broadly covering the upper surface of the ultraviolet-transparent transparent plate 4, and flows out through the outlet 6, so that the liquid is not removed from the mercury lamp. The generated heat rays and radiant heat are blocked by the cooling liquid tank, and only the ultraviolet rays are transmitted.The irradiated object on the conveyor undergoes the irradiation treatment without any particular temperature rise, so the base material and coating film of the irradiated object are UV-curable paint can be cured without thermal deformation.

FIG. 2 shows an irradiation device having a mercury lamp 9 and a reflector 10 facing each other on both sides, and a tunnel including two rigid ultraviolet-transmitting transparent plates 11 as a cooling device B, and a tunnel along which the tunnel is viewed from above. This shows an example using a refrigerant liquid that flows downward in a film shape.

A conveyor 13 for conveying a workpiece 12 is installed in a tunnel including two rigid ultraviolet-transmitting transparent plates 11 so as to run therein.

There is a refrigerant liquid outlet 14 above the tunnel including the external light transmitting transparent plate 11, and a refrigerant liquid outlet 15 below.
is provided.

In such a device, the refrigerant liquid is continuously supplied and flows down while coating the outer surface of the ultraviolet-transparent transparent plate 11 in the form of a film, so that the heat source and radiant heat generated from the mercury lamp are blocked by the cooling device B. The object to be treated 12 suspended on the conveyor 13 undergoes the irradiation treatment without any particular temperature rise, allowing only ultraviolet rays to pass through, so that the substrate and coating of the object to be treated are not thermally deformed. It is possible to perform curing treatment for ultraviolet curable paints.

The heat shielding effect of the embodiment shown in FIG. 1 is as follows.

In other words, a 2KW mercury lamp is placed on the conveyor with 20crIL.
A transparent acrylic plate with a thickness of 2 mrn was used as the bottom of the tank, and water was flowed on the surface at a flow rate of 500 cc per minute, interposed between the mercury lamp and the conveyor. Thickness, 10Cr
When the surface temperature of the IL square ABS plate was measured immediately after irradiation, it was found to be 30° C. or lower at room temperature.

After that, for comparison, the cooling device was removed and direct irradiation was performed, and the surface temperature was 70°C at 2 m/min.
The temperature was 100°C at 1m/min.

The ABS board was screen-printed with ultraviolet ray curable ink and then subjected to irradiation treatment, and the ink was sufficiently cured in all four cases.

In the present invention, the ultraviolet transmitting transparent plate is 150~
Acrylic resin plates that allow light in the 400 nm wavelength range to pass through well, heat-absorbing glass plates such as Pyrex glass, quartz glass plates, and ordinary inorganic glass are used.

Water, oil, etc. are used as the cold parent liquid, and any suitable method such as overflow or showering can be used to drain the liquid.

It is also advantageous to recycle the water using a cooling device.

When water is used for cooling, if the evaporation of water affects the lamp on the mercury lamp side, create an air flow between the cooling medium and the mercury lamp to perform intake and exhaust. It is preferable.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment effective for irradiating a horizontal surface, and FIG. 2 is a perspective view showing an embodiment effective for irradiating a vertical surface. 1...Mercury lamp, 2...Reflector, 4
..... Ultraviolet transmitting transparent plate, A .... Cooling liquid tank, 8 .... Irradiated object, 9 .... Mercury lamp, 10 .... Reflective umbrella, 11... Ultraviolet transmitting transparent plate, B... Cooling device, 12...
・Irradiated object.

Claims (1)

[Claims] 1. In an apparatus for irradiating an object to be irradiated using a mercury lamp as an irradiation source, an ultraviolet-transmitting transparent plate is provided between the object to be irradiated and the irradiation source, and a film flow is formed along the transparent plate. An ultraviolet irradiation treatment device with a cooling device consisting of a refrigerant liquid. 2. The ultraviolet rays according to claim 1, which uses, as a cooling device, a liquid tank whose horizontal bottom is formed of an ultraviolet-transparent transparent plate, and which has a refrigerant liquid inlet on one side and a refrigerant liquid outlet on the other side. Irradiation treatment equipment. 3. The ultraviolet irradiation treatment apparatus according to claim 1, which uses a rigid ultraviolet-transmitting transparent plate and a refrigerant liquid flowing in a film form from above to below along this plate as a cooling device.