WO2010084771A1

WO2010084771A1 - Metal halide lamp

Info

Publication number: WO2010084771A1
Application number: PCT/JP2010/000386
Authority: WO
Inventors: 藤岡純; 田内亮彦
Original assignee: ハリソン東芝ライティング株式会社
Priority date: 2009-01-26
Filing date: 2010-01-25
Publication date: 2010-07-29
Also published as: CN102292793B; KR20110119630A; CN102292793A; JPWO2010084771A1; TW201039372A

Abstract

A metal halide lamp emitting ultraviolet light having a wavelength of 350 to 380 nm, which comprises: an air-tight container (11) comprising an ultraviolet light-permeable quartz glass and being provided with an air-tight discharge space (10); a pair of discharge electrodes (121, 122) that are positioned in the air-tight container and face each other along the axial direction; and an enclosed material comprising a rare gas in an amount sufficient for maintaining the arc-discharged state in the discharge space, mercury and an appropriate amount of thallium and a halogen capable of providing ultraviolet light emission. By irradiating an ultraviolet light-curable resin composition containing a photopolymerization initiator with the ultraviolet light emitted from the aforesaid metal halide lamp, the curing speed of the resin composition can be increased.

Description

Metal halide lamp

The present invention relates to a metal halide lamp that is used to act on a photoinitiator having an absorption wavelength region in a specific section with high luminous efficiency, and more specifically, to increase the luminous efficiency of ultraviolet light of a specific wavelength to obtain a high light quantity. The present invention relates to a metal halide lamp in which the curing rate of an ultraviolet curable resin composition containing a photoinitiator is increased.

JP-A-2007-525540 discloses a device that uses ultraviolet rays emitted from an ultraviolet lamp to contain a photoinitiator in a resin composition that can be cured in a specific absorption wavelength range, and accelerates the curing of the composition. Is known.

In the technique described in this publication, an iron-based metal halide lamp is used as a light source for irradiating a photoinitiator having an absorption wavelength region with a long wavelength ultraviolet ray of 350 to 380 nm. The lamp has a broad wavelength region between 350 and 380 nm, but the amount of light of a single wavelength is not so high, and there is a problem that it takes time to cure.

Special Table 2007-525540

An object of the present invention is to provide a metal halide lamp capable of increasing the light emission efficiency of ultraviolet light of a specific wavelength to obtain a high light quantity and increasing the curing speed of the ultraviolet curable resin composition containing a photoinitiator. It is in.

A metal halide lamp according to one aspect of the present invention is a metal halide lamp that irradiates ultraviolet rays to an ultraviolet curable resin composition containing a photoinitiator having an absorption wavelength range of at least 350 to 380 nm of long wavelength ultraviolet rays. An airtight container made of an ultraviolet light transmissive material, a discharge electrode made of a pair of refractory metals and sealed in the airtight container, and an enclosure sealed in the airtight container containing argon gas, mercury and thallium halide. It is characterized by having.

According to the metal halide lamp of the present invention, when the photoinitiator having an absorption wavelength region between 350 and 380 nm is irradiated, the luminous efficiency is higher than that when the conventional iron-based metal halide lamp is irradiated with ultraviolet rays. And the curing rate of the curable resin composition containing the photoinitiator can be improved.

It is a basic structure figure for demonstrating one Embodiment regarding the metal halide lamp of this invention. It is the block diagram which expanded and showed a part of FIG. It is explanatory drawing for demonstrating each absorption factor with respect to the light emission wavelength of a different photoinitiator. It is explanatory drawing for demonstrating Example 1 of this invention and the conventional spectral distribution and light quantity. It is explanatory drawing which expanded and showed (a) of FIG. It is explanatory drawing for demonstrating the effect of Example 1 of this invention and the conventional photoinitiator. It is explanatory drawing for demonstrating the relationship between the spectrum and illuminance which make the thallium-type metal halide lamp axial direction right and left in the case of the thallium iodide enclosure amount being 0.040 mg / cc. It is explanatory drawing for demonstrating the relationship between the spectrum and illumination intensity which make the thallium-type metal halide lamp axial direction right and left in the case of the thallium iodide enclosure amount being 0.036 mg / cc. It is explanatory drawing for demonstrating the quality of the cure ratio of the thallium iodide enclosure amount and photoinitiator 4.4'-bis (diethylamino) benzophenone. It is explanatory drawing for demonstrating the quality of the hardening ratio of the thallium iodide enclosure amount and the photoinitiator 4.4'-bis (dimethylamino) benzophenone.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

FIG. 1 is a basic structural diagram for explaining an embodiment relating to a metal halide lamp of the present invention, and FIG. 2 is a configuration diagram showing an enlarged part of FIG.

1 and 2,

electrodes

121 and 122 made of, for example, a tungsten material are spaced apart from each other at both ends in the longitudinal direction of an airtight container 11 made of quartz glass having ultraviolet transparency and having a discharge space 10 formed therein. Are arranged. The

electrodes

121 and 122 are welded to one end of

metal foils

141 and 142 made of, for example, molybdenum via

inner leads

131 and 132, respectively. One end of an outer lead (not shown) is welded to the other end of the

metal foils

141 and 142. The portions of the

metal foils

141 and 142 in the hermetic container 11 are sealed by heating the corresponding hermetic container 11 from the

inner leads

131 and 132 to one end of the outer lead.

The

metal foils

141 and 142 may be any material that has a thermal expansion coefficient close to that of the quartz glass forming the hermetic container 11, but here, general molybdenum is used as a material suitable for this condition.

Lead wires

161 and 162 for power feeding are electrically connected to the outer leads whose one ends are connected to the

metal foils

141 and 142, respectively, in the

sockets

151 and 152 made of heat resistant and insulating materials, for example. ing. The

sockets

151 and 152 insulate and seal the

lead wires

161 and 162. A power circuit (not shown) is connected to the

lead wires

161 and 162.

In the airtight container 11, argon gas necessary for maintaining arc discharge is enclosed at 1.3 kPa as an enclosure, and iron, Hg (mercury), etc., which are metals for emitting ultraviolet light, are enclosed. Has been.

The metal halide lamp configured as described above can be irradiated with ultraviolet rays by iron, which is a light-emitting metal having spectral characteristics in the ultraviolet region. This ultraviolet curable resin composition irradiated with ultraviolet rays contains a photoinitiator that initiates polymerization of the polymerizable resin of the resin composition when irradiated with the ultraviolet rays.

Photoinitiators include (a) 4.4′-bis (diethylamino) benzophenone, (b) 4-diethylaminoacetophenone, (c) 4-dimethylaminoacetophenone, (d) benzyl, (e) thioxanthone, (f) Benzophenone, (g) 4.4′-bis (dimethylamino) benzophenone, and the like are conceivable.

FIG. 3 is an explanatory diagram for explaining the respective absorption rates with respect to the emission wavelengths of the respective photoinitiators (a) to (g). Here, among the photoinitiators (a) to (g), photoinitiators (a) and (g) having a high absorptance with respect to the emission wavelength in the wavelength region of at least 350 to 380 nm are used.

Hereinafter, in a lamp composed of a single tube having an outer diameter φ of 27.5 mm, a wall thickness m of 1.5 mm, and a light emission length L of 1000 mm, a lamp using iron as the light emitting metal, and thallium Of the present invention in which a photo-initiator having an absorption wavelength region in at least 350 to 380 nm of ultraviolet light is accelerated, compared with the embodiment of the present invention in which benzene is encapsulated as a luminescent metal. An example will be described.

In addition, as a photoinitiator in each of the following examples, a comparison was made with the conventional case where 4.4′-bis (diethylamino) benzophenone of (a) was irradiated with ultraviolet rays of an iron-based metal halide lamp. Yes.

(Embodiment 1) In Embodiment 1, argon gas necessary for maintaining arc discharge is 1.3 kPa as an enclosed material in the hermetic vessel 11, mercury, and thallium iodide, which is a metal for emitting ultraviolet rays. A thallium-based metal halide lamp encapsulating a chemical was produced.

The photoinitiator contained in the curable resin composition is ultraviolet light from the thallium-based metal halide lamp and ultraviolet light from an iron-based metal halide lamp in which iron is enclosed as a metal for emitting ultraviolet light. -The effect on bis (diethylamino) benzophenone will be described.

Here, let us consider a case in which the thallium metal halide lamp and the iron metal halide lamp are irradiated with ultraviolet rays with the same specifications of an input power of 12000 W, a lamp voltage of 1100 V, and a lamp current of 10.9 A, respectively. FIG. 4 shows the spectral distribution and light amount of the thallium metal halide lamp and the iron metal halide lamp of the present invention. As is clear from FIG. 4, the thallium-based metal halide lamp is excellent in the 350 to 380 nm long wavelength ultraviolet rays required for curing the photoinitiator contained in the resin composition.

FIG. 5 shows only the absorptance of the photoinitiator (a) 4.4′-bis (diethylamino) benzophenone in FIG. 3 (a) with respect to the emission wavelength.

When the emission spectrum curve of the metal halide lamp is α (λ) and the absorption spectrum curve of the photoinitiator is φ (λ), the reaction between the lamp used and the photoinitiator is expressed by the following equation. As shown in FIG. 5, a indicates a wavelength with a low emission spectrum, and b indicates a wavelength with a high emission spectrum.

Here, when the initiation effect ratios of the thallium-based metal halide lamp and the iron-based metal halide lamp with the photoinitiator were compared when the wavelength a of the emission spectrum was 350 nm and the wavelength b was 380 nm, the results shown in FIG. 6 were obtained. It was.

That is, when the iron metal halide lamp is 100%, the thallium metal halide lamp is 112%. This indicates that when the curable resin composition containing the photoinitiator 4.4'-bis (diethylamino) benzophenone is irradiated with ultraviolet rays from a thallium-based metal halide lamp, the curing rate is improved by 12%.

In this embodiment, when a photoinitiator having an absorption wavelength region between 350 and 380 nm is irradiated with ultraviolet light from a thallium-based metal halide lamp, the photoinitiator is irradiated with conventional ultraviolet light from an iron-based metal halide lamp. In addition, the luminous efficiency can be increased, and the curing rate of the curable resin composition can be improved. In Example 1, although the lamp | ramp which enclosed the thallium iodide was demonstrated as an example, it is not limited to iodide, The same effect is acquired even if it encloses as another halide. That is, what is necessary is just to enclose as a compound which thallium evaporates easily in an airtight container during arc discharge.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 7 and FIG. 8 show the measurement results of the relationship between the spectral and illuminance with the axial direction of the metal halide lamp on the left and right in the lamps with a light emission length of 1000 mm and different amounts of thallium iodide. Show. FIG. 7 shows the case where the amount of thallium iodide enclosed is 0.040 mg / cc, and FIG. 8 shows the case where the amount of thallium iodide enclosed is 0.036 mg / cc.

When ultraviolet light is irradiated when the amount of thallium iodide enclosed in FIG. 7 is 0.040 mg / cc, separate light emission occurs in the axial direction and the left and right spectral distributions are different, which may adversely affect the irradiated object. There is sex. The problem due to the separated light emission is particularly remarkable in a lamp having a light emission length of 200 mm or more.

The difference in spectral distribution between the left and right is due to the difference in the amount of thallium iodide on the left and right sides of the valve because of the saturation vapor pressure of thallium iodide. It is considered a thing.

When ultraviolet light is irradiated when the amount of thallium iodide enclosed in FIG. 8 is 0.036 mg / cc, the generation of separated light emission is not seen in the axial direction, and the left and right spectra have the same distribution, and the object is irradiated. On the other hand, high uniformity was obtained. Therefore, it is possible to improve the curing rate of the curable resin composition by obtaining a high degree of uniformity from side to side.

FIG. 9 illustrates the ratio of curing times when the photoinitiator 4.4′-bis (diethylamino) benzophenone is irradiated with ultraviolet rays using the iron metal halide lamp and the thallium-based metal halide lamp according to the embodiment. It is explanatory drawing.

That is, when the amount of thallium iodide enclosed is 0.01 mg / cc or more, the curing time by the metal halide lamp according to the embodiment is 101% or more with respect to the curing time by the iron metal halide lamp. When the amount of thallium iodide is 0.006 mg / cc or less, the curing time by the metal halide lamp according to the embodiment is not more than the curing time by the iron metal halide lamp. However, when the amount of thallium iodide is 0.04 mg / cc or more, although the curing time is improved, as described above, there is a problem that light emission separation occurs and a place where the hardening time is early and a time late.

Therefore, when the amount of thallium iodide contained in the thallium-based metal halide lamp that irradiates the photoinitiator 4.4'-bis (diethylamino) benzophenone with ultraviolet rays is 0.01 to 0.036 mg / cc, the iron metal halide lamp It was found that advantageous results were obtained compared with the case of using.

FIG. 10 shows the ratio of the curing times when the photoinitiator 4.4′-bis (dimethylamino) benzophenone is irradiated with ultraviolet rays using the iron metal halide lamp and the thallium metal halide lamp according to the embodiment. It is explanatory drawing explaining about.

In this case, when the amount of thallium iodide enclosed is 0.006 mg / cc or more, the curing time by the metal halide lamp according to the embodiment is 101% or more with respect to the curing time by the iron metal halide lamp. When the amount of thallium iodide is 0.002 mg / cc or less, the curing time by the metal halide lamp according to the embodiment is not more than the curing time by the iron metal halide lamp. However, when the amount of thallium iodide is 0.04 mg / cc or more, although the curing time is improved, there is a problem that light emission separation occurs and a place where the curing time is early and a place where it is late is generated.

Therefore, when the amount of thallium iodide contained in the thallium-based metal halide lamp that irradiates the photoinitiator 4.4′-bis (dimethylamino) benzophenone with ultraviolet rays is 0.006 to 0.036 mg / cc, the iron metal halide lamp It was found that advantageous results were obtained compared with the case of using.

From these facts, it can be seen that the curing rate of the curable resin composition having a high absorptance with respect to long wavelength ultraviolet rays of 350 to 380 nm cannot be improved even if the amount of thallium iodide enclosed is too much or too little.

Accordingly, as the amount X (mg / cc) of thallium iodide which is a condition for improving the curing rate of a curable resin composition having a high absorption rate at 350 to 380 nm, 4.4′-bis (diethylamino) benzophenone is In the case of a photoinitiator, it was found to be in the range of 0.01 to 0.036. It was also found that when 4.4'-bis (dimethylamino) benzophenone is a photoinitiator, it is within the range of 0.006 to 0.036.

According to this embodiment, it becomes possible to improve the curing rate of the ultraviolet curable resin composition containing a photoinitiator having a high absorption wavelength region in a long wavelength ultraviolet ray of 350 to 380 nm.

Claims

A metal halide lamp for irradiating an ultraviolet curable resin composition containing a photoinitiator having an absorption wavelength region in a long wavelength ultraviolet ray of at least 350 to 380 nm,
An airtight container made of an ultraviolet light permeable material;
A discharge electrode made of a pair of refractory metals and sealed in the hermetic container;
A metal halide lamp comprising: an enclosure containing argon gas, mercury, and thallium halide, and enclosed in the hermetic container.
The metal halide lamp according to claim 1, wherein the photoinitiator contains 4.4'-bis (diethylamino) benzophenone.
The thallium halide contained in the enclosure is thallium iodide,
The metal halide lamp according to claim 2, wherein the amount of thallium iodide enclosed X (mg / cc) is 0.01≤X≤0.036.
2. The metal halide lamp according to claim 1, wherein the photoinitiator is 4.4'-bis (dimethylamino) benzophenone.
The thallium halide contained in the enclosure is thallium iodide,
5. The metal halide lamp according to claim 4, wherein the amount of thallium iodide enclosed X (mg / cc) is 0.006 ≦ X ≦ 0.036.