JPH0754695B2 - Heater lamp - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heater lamp that emits orange or orange-red color.

[Prior art and its problems]

A heater lamp designed to have a low color temperature is often used as a heat source for electric appliances such as household heating appliances and microwave ovens. This is because the heater lamp has advantages such as high thermal efficiency and quick start-up. In these electric products, infrared rays emitted from a heater lamp are used as a heat source, but visible light is also emitted from the heater lamp. Therefore, when white visible light enters the eyes during use, it is very dazzling because of the high brightness.
In addition, white visible light gives a cold feeling, which is not preferable in heating appliances.

Therefore, the visible light with a short wavelength is cut to reduce the brightness and allow only the red or orange-red to pass therethrough to prevent glare and to give a visually warm feeling or a feeling of heating at high temperature. ing. As a method of cutting visible light having a short wavelength and transmitting red light, conventionally, quartz glass doped with copper oxide has often been used for an arc tube of a heater lamp.

However, in order to dope copper oxide with copper oxide,
The process was complicated and expensive. Further, when doped with copper oxide, it tends to be in the state of CuO, so this is reduced to Cu ₂ O and a red color is produced. However, since the heater lamp is turned on in an oxidizing atmosphere, Cu ₂ O is gradually oxidized during use to give a reddish color, and there is a problem that performance is deteriorated. Further, the effect of reducing the color temperature is not always sufficient, and it is somewhat dazzling when directly looking at the heater lamp.

[Object of the Invention]

Therefore, the present invention is easy to manufacture and surely radiates orange or orange-red to sufficiently reduce the brightness and has a low color temperature and a large antiglare effect, and does not fade even after long-term use. It is an object of the present invention to provide a heater lamp which has excellent durability and is suitable as a heat source for electric appliances such as household heating appliances and microwave ovens.

[Structure of Invention and Its Action]

In the heater lamp of the present invention, a coating film of Fe ₂ O ₃ is formed on the outer surface and / or the inner surface of an arc tube made of quartz glass, and this Fe ₂ O ₃ coating film is formed by adding water to titanium alcoholate. It is characterized in that it is covered with a titanium oxide film formed by firing the sol-like dispersion of the titanium compound.

In other words, this Fe ₂ O ₃ coating forms Fe on the surface of quartz glass.
It can be easily formed by applying the alcoholate solution of (3) by dipping or the like, drying and baking at 500 ° C. or higher, preferably 700 ° C. or higher. Then, a TiO ₂ film can also be formed by applying a sol-like dispersion of a titanium compound produced by adding water to a titanium alcoholate solution on the Fe ₂ O ₃ film and performing the same operation. As the hydrolysis of the titanium alcoholate solution proceeds, the sol-like dispersion becomes huge. When the titanium compound in this state is applied and fired, the obtained TiO ₂ layer is composed of TiO ₂ crystals having a large particle diameter, so that a coating film with severe irregularities is formed. Therefore, although these coatings can be easily formed,
Since the coating film of Fe ₂ O ₃ has a property of cutting off light having a wavelength of about 500 nm or less, the heater lamp according to the present invention emits orange or orange red color, and the brightness is lowered. In addition, this property does not deteriorate, and since the Fe ₂ O ₃ coating is covered with a hard TiO ₂ coating, it is difficult to scratch or peel off,
It has excellent durability. The TiO ₂ coating has a very large surface irregularity and a significantly large light-diffusing effect, so that the color temperature is sufficiently lowered, and the glare is completely eliminated when the heater lamp is directly viewed.

〔Example〕

The present invention will be specifically described below based on the embodiments shown in the drawings.

FIG. 1 shows a heater lamp used as a heat source for the "Kotatsu", which is an incandescent lamp rated at 100V-400W. The arc tube 1 is a quartz glass tube having an outer diameter of 10 mmφ, and both ends thereof are pressure-bonding sealing parts 2. Molybdenum foil 3 is sealed in the pressure-bonding sealing parts 2. The luminous filament 4 is arranged along the axis of the arc tube 1 and both ends thereof are connected to the molybdenum foil 3, respectively, and the heater lamp emits light when the lead wires 5, 5 extending from the pressure-sealing portion 2 to the outside are energized. . Then, on the outer surface of the arc tube 1, for convenience but coating 6 indicated by dotted lines are formed, the coating film 6, as shown in FIG. 2, the outer surface of the arc tube 1, first of all, Fe ₂ O _{A three-} layer coating 61 is formed, and a TiO ₂ coating 62 is formed on the Fe ₂ O ₃ coating 61 to form a double layer.

Here, the method of forming the coating 6 will be described. First, the outer surface of the arc tube 1 is ultrasonically cleaned with isopropyl alcohol. Then, the arc tube 1 is dipped in an Fe alcoholate solution having a concentration of 3% in terms of Fe ₂ O ₃ and pulled up at a speed of about 50 cm / min. This causes the alcoholate solution of Fe to adhere to the outer surface of the arc tube 1, which is dried at 150 ° C. for 10 minutes. Next, this was baked at 700 ° C for 10 minutes to produce Fe ₂ O ₃
Coating 61 is formed. Then, the above steps are repeated several times to make the film thickness of the coating film 61 to a predetermined value.
About 0.03 to 0.35 μm is suitable. When the thickness is 0.03 μm or less, the transmittance of light having a wavelength of 500 nm or less is high and the brightness is not sufficiently reduced. On the other hand, when the thickness is 0.35 μm or more, the coating film 61 is likely to be peeled off, and the number of forming steps is increased, which is wasteful. Next, water is added to an alcoholate solution of Ti having a concentration of 5% in terms of TiO ₂ to allow hydrolysis to proceed, and the arc tube 1 is dipped into a solution in which a titanium compound is dispersed in a sol state to form a sol of the titanium compound. The porous dispersion is adhered, and a TiO ₂ coating 62 having a film thickness of about 0.05 μm to 1 μm is formed by the same drying and firing operations. As shown in FIG. 2, the TiO ₂ coating 62 has very severe surface irregularities.

In this way, the coating 6 can be formed only by the dipping, drying and firing operations, so that the process is very simple. In this example, the coating 6 is formed on the outer surface of the arc tube 1. However, the coating 6 is formed on the inner surface or only on the inner surface by dipping before sealing both ends. May be.

Then, the coating 61 of Fe ₂ O _{3 is} formed on the outer surface of the arc tube 1 with a thickness of
Coating 6 with an average thickness of 0.05 μm and TiO ₂ coating 62 of 0.1 μm
After turning on the heater lamp, the spectral transmittance was checked, and as a result, the transmittance of light with a wavelength of 500 nm or less was 40% or less, increasing in the range of 500 to 700 nm and increasing to about 80 at 700 nm.
%Met. Therefore, visible light having a short wavelength is cut off and only orange or orange-red is emitted, and the brightness is lowered. Further, since the TiO ₂ coating 62 is made of a film having severe irregularities, the light scattering effect is extremely large and it is effective in reducing the color temperature, but the color temperature at this time was about 2100K. Then, the glare when directly looking at the heater lamp is completely eliminated. Therefore, when the heater lamp using the arc tube 1 is used as a heat source of an electric product, it is possible to visually give a warm feeling or a feeling of heating at a high temperature.
Then, after the heater lamp was turned on for 5000 hours, there was almost no change even if the spectral transmittance of the arc tube 1 was measured,
Further, since the outermost layer is covered with the hard TiO ₂ coating 62,
It was confirmed that the product was not scratched or peeled off, and had sufficient durability as a heat source for household electrical appliances used under various conditions.

〔The invention's effect〕

As described above, the heater lamp of the present invention is provided with Fe ₂ O on the outer surface and / or the inner surface of the quartz glass arc tube.
A coating of ₃ is formed, and a hard TiO ₂ coating that is hard and has an excellent light-scattering effect is formed on this Fe ₂ O ₃ coating, so it is easy to manufacture and is surely orange-red or orange-red. And the luminance color temperature is sufficiently reduced. Therefore,
The heater lamp is suitable for a heat source of electric appliances such as household heating appliances and microwave ovens, which give a visually warm feeling and have a very high anti-glare effect, and which requires great durability.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of an essential part. 1 ...... arc tube, 2 ...... crimp sealing portion 3 ...... molybdenum foil, 4 ...... emitting filament 5 ...... lead, 6 ...... film 61 ...... Fe ₂ O ₃ film, 62 ...... TiO ₂ coating

Claims (1)

[Claims] 1. A coating of Fe ₂ O ₃ is formed on the outer surface and / or the inner surface of a quartz glass arc tube. This Fe ₂ O ₃ coating is formed by adding water to titanium alcoholate. A heater lamp characterized by being covered with a titanium oxide film formed by firing a sol-like dispersion of a titanium compound.