JPH02253554A - Ultraviolet-ray shielding lamp and its manufacture - Google Patents

Abstract

PURPOSE:To realize an efficient shielding of ultraviolet rays, a good permeability to a visible ray, and the maintaining of a low scattering performance, by spreading a slurry made by spreading a zinc oxide powder in a binder. CONSTITUTION:On the surface of the bulb of a discharge lamp or a haloid lamp, an ultraviolet-ray absorbing membrane 1 is formed. The ultraviolet-ray absorbing membrane 1 is formed by spreading a slurry made by spreading a zinc oxide powder in a binder, preferably at the mixing ratio within 2:1 and 1:2, and less than 0.1mum. As the binder, a substance with the heat-resistance, a transparency, a good film forming property, a good adhesive property with the basic material, and a thermal expansion coefficient at the level same as the basic material, such as a silica colloid, for example, is used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ultraviolet shielding lamp that emits less ultraviolet radiation and a method for producing the same. In particular, the present invention relates to an ultraviolet shielding lamp that reduces ultraviolet radiation by providing an ultraviolet absorbing film made of zinc oxide powder between the light emitting source of the lamp and the bulb, and a method for manufacturing the same.

[Prior art and problems to be solved by the invention] As lighting with high brightness, high efficiency, and long life, mercury lamps, metal halide lamps,
Discharge lamps such as sodium lamps, xenon lamps, and halogen lamps are used. Such discharge lamps emit strong ultraviolet rays in addition to visible light. Furthermore, as lamps have become more bright these days, ultraviolet radiation from halogen lamps and the like cannot be ignored.

In store lighting, ultraviolet rays cause discoloration and deterioration of products, and in fishing lamps, ultraviolet rays cause sunburn, skin cancer, and visual impairment for fishermen, so it is desirable to reduce the radiation emitted from lighting lights. ing. Therefore, the following proposals have been made to reduce the ultraviolet radiation from illumination lamps. That is, (υ metal vapor discharge lamp, a lamp in which ultraviolet radiation is reduced by forming titanium oxide on the outside or inside of the lamp, ■ xenon lamp, the bulb is coated with 10 to 300 ppm of either titanium oxide or cerium oxide, or both). There are lamps that have reduced ultraviolet radiation by being made of transparent quartz glass containing

This is done by coating the outside or inside of the outer bulb of a steam lamp with titanium oxide as an ultraviolet absorber.
When using titanium oxide, there are the following problems.

(D titanium oxide has a high refractive index, lacks transparency, and reduces lamp brightness.

(2) When titanium oxide powder is used, the particle size is large and visible light is absorbed, reducing the brightness of the lamp and impairing color rendering.

(3) When using an organic titanium compound, it is not possible to increase the film thickness, and sufficient absorption of ultraviolet rays cannot be obtained.

In addition, method (2) above is expensive because the pulp material of the lamp is special, it cannot use conventionally manufactured bulbs, and there is a limit to the amount of ultraviolet absorber added, so There are problems such as the inability to obtain an absorption effect.

In addition, conventional UV coating materials include those that have the ability to cut (block) light from the immediate vicinity of D400nm;
No coating material has been found that satisfies all of the following conditions: (G) being stable in itself; and (G) being harmless to the human body.

Therefore, the present invention provides a lamp having an ultraviolet absorbing coating layer that efficiently blocks ultraviolet rays and has good transparency and low scattering property for other effective light rays such as visible light, and a method for manufacturing the same. aim to do. That is, the present invention adds zero zinc oxide powder to a conventional lamp.
．． By applying a slurry dispersed to 1 μm or less, it is easy to manufacture and does not impair the brightness or color rendering of the lamp.
An object of the present invention is to provide an ultraviolet shielding lamp with reduced ultraviolet radiation and a method for manufacturing the same.

[Means for Solving the Problems] The gist of the present invention is to apply a slurry in which zinc oxide powder is dispersed in a binder to one or both of the outer surface and inner surface of a bulb of a discharge lamp or a halogen lamp. This is an ultraviolet shielding lamp that has a layer coated and formed. Furthermore, the present invention is a discharge lamp having an arc tube and an outer bulb, and is an ultraviolet shielding lamp having a layer formed by coating the outer surface of the arc tube with a slurry in which zinc oxide powder is dispersed in a binder. The present invention also provides a method for producing an ultraviolet shielding lamp by applying a slurry containing zinc oxide powder dispersed in a binder to either or both of the outer or inner surfaces of a bulb of a discharge lamp or a halogen lamp. Furthermore, the present invention is a method for manufacturing an ultraviolet shielding lamp by applying a slurry containing zinc oxide powder dispersed in a binder to the outer surface of the arc tube of a discharge lamp having an arc tube and an outer bulb to form an ultraviolet shielding layer. .

The present inventors have discovered that all the problems of the prior art can be solved by coating with a slurry in which zinc oxide powder is dispersed to a particle size of 0.1 μm or less, and have arrived at the present invention.

That is, the present invention can be easily manufactured by applying a slurry in which zinc oxide powder is dispersed in a particle size of 0.1 μm or less to an ordinary lamp that has been used in the past, and does not impair the brightness and color rendering properties of the lamp. It is an object of the present invention to provide a method for manufacturing an ultraviolet shielding lamp with reduced ultraviolet radiation.

The zinc oxide powder used in the present invention has a −order number of 0.1 μm.
The zinc oxide powder should be uniformly dispersed in the binder, and the dispersed particle size should be less than or equal to 0.1
The single dispersed particle size, which must be less than μm, is 0.1 μm.
If it exceeds m, absorption of visible light occurs and the brightness of the lamp,
Color rendering is impaired.

In order to uniformly disperse the zinc oxide particles in the binder of the slurry, a solvent that dissolves the binder well or any known dispersion method such as a ball mill, sand mill, attritor, triple roll, homogenizer, or paint shaker may be used. There is no limitation in any way, and any of them can be used alone or in combination.

The binder for slurry used in the present invention has heat resistance, is transparent, sufficiently disperses and fixes zinc oxide powder, has good film forming properties, has good adhesion to the substrate, and has good adhesion to the substrate. It is preferable to use a material with a coefficient of thermal expansion comparable to that of the material. As such, heat-resistant binders such as silica colloid, polysiloxane, polyporosiloxane, polycarbosilane, and polyphosphazene are suitable. As the silica colloid, aqueous silica sol, silicon alkoxide hydrolyzate, etc. are used. As the polysiloxane, a hexapolar silicone resin can be used. Metal ions or boron may be added to these binders for the purpose of matching thermal expansion with the base material.

The mixing ratio of zinc oxide powder and binder ranges from 10:1 to 1:1O5, preferably from 2:1 to 1:2. If the amount of zinc oxide powder is less than this, sufficient ultraviolet absorption effect cannot be obtained, and if it is too much, sufficient film strength cannot be obtained. If it exceeds, sufficient film strength cannot be obtained,
If the ratio is less than 1:10, a sufficient ultraviolet absorption effect cannot be obtained, which is also disadvantageous.

The zinc oxide slurry can be applied to the surface of the lamp, for example, by dip coating, spray coating, flow coating, brush coating, or the like.

The slurry may be applied anywhere between the light emitting source and the object to be illuminated; that is, in the case of xenon lamps and halogen lamps, it is applied to either or both of the outside and inside of the bulb. In mercury lamps, metal halide lamps, and sodium lamps, it is the outside and/or inside of the outer bulb, or the outside of the arc tube.

It is preferable that the coating thickness of the coating layer be the minimum required to absorb ultraviolet rays. This is because if the coating thickness is increased, the strength and adhesion of the film will decrease, impairing the brightness and color rendering properties of the lamp. Although it depends on the mixing ratio of zinc oxide powder and binder, the particle size of zinc oxide' is usually in the range of 0.5 to 50 am, preferably in the range of 3 to 30 μm.

The material for the slurry used in the present invention was developed based on the following findings.

Zinc oxide has an ultraviolet absorption edge of 38 On+m and 40 On+m.
It is very close to 0n-, and as the particle size is reduced, it becomes transparent and has a very sharp light absorption edge, whereas it is normally seen as a white pigment and has strong light scattering and poor translucency. It was discovered that this is an ideal type of ultraviolet absorbing material. It has been discovered that by mixing this with a binder, a coating layer with excellent ultraviolet absorption, light transmission, and visible light scattering properties can be produced.

FIG. 1 shows the structure of a lamp according to the invention.

That is, the surface of the quartz glass 2 of the outer bulb of a conventional halogen lamp has a layer formed by coating a zinc oxide powder slurry, that is, an ultraviolet absorbing film 1, according to the present invention. That is, the film 1 is formed in such a way that it is exposed to the outside air 3, the tungsten filament 4 emits luminescent radiation, and the ultraviolet rays contained therein are absorbed by the film 1.

FIG. 4 shows the structure of a mercury lamp according to the present invention.

That is, the ultraviolet absorbing film 2 is coated on the surface of the outer bulb 2 of a mercury lamp according to the present invention, and is exposed to the outside air 3. A mercury lamp emits light from an arc tube 6 having a main electrode 4 and an auxiliary electrode 5, has a support rod 7 that also serves as a lead wire, and has a starting resistor 9. Power is supplied from a cap 8 to the lead wire. .

FIG. 7 also shows that according to the present invention, an ultraviolet absorbing film 1 is provided on the surface of the inner arc tube 6, and as shown in a partially enlarged view, the film 1 is in an atmosphere of a filler gas 10. , the other structure is the same as that shown in FIG.

Next, the ultraviolet shielding lamp according to the present invention will be specifically explained using Examples, but the present invention is not limited thereto.

[Example 1] 100 parts by weight of tetraethoxysilane, 300 parts by weight of isopropyl alcohol! l parts, 0. 35 parts by weight of IN hydrochloric acid to 60 parts by weight
The mixture was stirred at ℃ for 2 hours to react, and a silica colloid liquid was prepared. In this, grain go, oos~0.02μmty)fp
30 parts by weight of zinc oxide particles were mixed and dispersed for 2 hours using a sand mill to prepare a coating solution.

This liquid contained 99% by weight of particles of 0.1 μm or less. A 100W halogen lamp was immersed in this solution, pulled up at a constant speed, and dried at 150"C for 15 minutes. As shown in Figure 1, this zinc oxide solution was applied to a 1kIrI lamp. .

The second flash shows the spectral characteristics before coating, and FIG. 3 shows the spectral characteristics after coating.

[Example 2] The same zinc oxide coating solution as in Example 1 was applied to the outside of the outer bulb of a 1000 W mercury lamp using a flow foot, and the process was dried twice. FIG. 4 shows the structure of the mercury lamp in cross section, FIG. 5 shows the spectral characteristics of the mercury lamp before coating, and FIG. 6 shows the spectral characteristics after coating.

[Example 3] The arc tube of a 1000 W mercury lamp was immersed in the same zinc oxide coating solution as in Example 1, pulled up at a constant speed, and dried twice. Further, the test was carried out at 500°C for 30 minutes. This luminous tube was enclosed in an outer tube made of porcelain glass. This is shown in the sectional view of FIG. 7, and the spectral characteristics after coating are shown in FIG.

[Comparative Example] Using the coating solution of Example 1, zinc oxide powder was applied with a particle size of 0.05 to 0.
A coating liquid was prepared using titanium oxide powder having a particle size of 1 Jm, and was applied to the outer surface of the outer bulb of a 1000 W mercury lamp in the same manner as in Example 2.

Table 1 shows the illuminance, the amount of ultraviolet radiation, the illumination intensity and the amount of ultraviolet radiation after lighting for 1000 hours for the lamps of Examples 1 to 3 and the comparative example.

That is, in Example 1, the values were measured at a distance of 10e- from the lamp. In Example 2.3 and Comparative Example, the values were measured at a position at a distance of 60 cm from the lamp.

It can be seen that in Examples 1 to 3, the illumination intensity of the lamp did not decrease after application, but rather increased, and there was no change in the ultraviolet absorption effect even after too much time.

[Effects of the Invention] The following remarkable technical effects were obtained by the lamp of the present invention.

By coating various lamps with a slurry in which zinc oxide particles are uniformly dispersed in a heat-resistant binder with a particle size of 0.1 μm or less, ultraviolet radiation is reduced without impairing the brightness and color rendering properties of the lamps. Second, it can be easily applied to ordinary lamps, and as a secondary effect, heat rays are reflected from the UV-absorbing film armor, and it has a heat-retaining effect, so it protects the interior of the lamp. temperature rises,
We were able to provide an economical lamp with UV blocking properties that has the effect of increasing brightness.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a halogen lamp according to the present invention. FIG. 2 is a diagram showing the spectral characteristics of a normal halogen lamp. FIG. 3 is a diagram showing the spectral characteristics of the halogen lamp according to the present invention. FIG. 4 is a sectional view showing the structure of another example of a mercury lamp according to the present invention. FIG. 5 is a diagram showing the spectral characteristics of a normal mercury lamp. FIG. 6 is a diagram showing the spectral characteristics of the mercury lamp according to the present invention. FIG. 7 is a sectional view showing the structure of another example of a mercury lamp according to the present invention. FIG. 8 is a diagram showing the spectral characteristics of the mercury lamp of FIG. 7 according to the present invention. Patent applicant Sumitomo Cement Co., Ltd. Agent Patent attorney Yutaka Kuramochi Figure 8 Housewife C0

Claims (4)

[Claims] (1) An ultraviolet shielding lamp characterized by having a layer formed by coating a slurry of zinc oxide powder dispersed in a binder on either or both of the outer surface and inner surface of the bulb of a discharge lamp or halogen lamp. . (2) A discharge lamp having an arc tube and an outer bulb, the ultraviolet rays according to claim 1, characterized in that the outer surface of the arc tube has a layer formed by applying a slurry in which zinc oxide powder is dispersed in a binder. shielding lamp. (3) A method for manufacturing a lamp according to claim 1, characterized in that a slurry in which zinc oxide powder is dispersed in a binder is applied to either or both of the outer surface or inner surface of a bulb of a discharge lamp or a halogen lamp. . (4) A second method characterized in that a slurry in which zinc oxide powder is dispersed in a binder is applied to the outer surface of the arc tube of a discharge lamp having an arc tube and an outer bulb to form an ultraviolet shielding layer.
The method for manufacturing the ultraviolet shielding lamp described in Section 1.