JPH1116542A - Tungsten halogen lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tungsten halogen lamp provided with a color temperature conversion filter of a high color temperature type which does not be stripped even under hot and humid conditions and presents blue color. SOLUTION: A subfilament 2a and a main filament 2b are provided parallel to the center axis in a heat-resistant and transparent glass bulb 1 made of silica glass, etc., and a reflector 4 is fitted to the subfilament 2a. Then, on an outer surface of the glass bulb 1, a color temperature conversion filter 8 formed by piling up at least one blue coloring membrane layer consisting of complex oxides of silicon oxide, cobalt oxide and phosphates is formed, further on it a protective membrane 9 consisting of silicon oxide or complex oxides of silicon oxide and phosphates is piled and formed, thus a tungsten halogen lamp where the color temperature conversion filter 8 can be prevented from being stripped is constructed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halogen lamp, and more particularly to a halogen lamp which emits high-purity white light and which is suitable for a headlight, a fog lamp, and a general light source for automobiles.

[0002]

2. Description of the Related Art A conventional halogen bulb used for a headlight and a fog lamp and a halogen bulb for general illumination are white light having a reddish tint. By reducing this red tint, the halogen bulb can be brought into a higher color temperature state. As a means for reducing the red tint, an optical thin film of a high color temperature type filter based on the optical interference theory in which a high refractive index layer such as titanium oxide and a low refractive index layer such as silicon oxide are alternately laminated is applied to the valve surface. Has been conventionally used as one effective method.

However, an optical thin film of a high color temperature type filter based on the optical interference theory in which a high refractive index layer and a low refractive index layer are alternately laminated is used in order to reduce color unevenness caused by its use. Various devices such as a film thickness and a laminating method and complicated operations are required.

In order to solve such a problem, the present inventor has disclosed in Japanese Patent Application No. Hei 8-16891 a simple and simple operation without forming a complicated operation for forming an optical thin film based on the theory of optical interference. A halogen lamp emitting high-purity white light and a method for manufacturing the same have been proposed. That is, the present invention has proposed a structure in which at least one layer of a color temperature conversion film of a blue colored film made of a composite oxide of silicon oxide, cobalt oxide, and phosphorus oxide is formed on the outer surface of a halogen bulb. By forming a color temperature conversion film composed of one or more blue colored films in this way, it is possible to easily obtain a halogen bulb that emits high-purity white light without color unevenness without requiring complicated operations. Was done.

Incidentally, the composition of the composite oxide constituting the color temperature conversion film of the blue colored film will be described in detail. The composite oxide of silicon oxide, cobalt oxide and phosphorus oxide has a mole fraction of 0.086 ≦ x ≦ 0.804, 0.194 ≦ y ≦ 0.623, 0.0
02 ≦ z ≦ 0.291 (x = SiO ₂ , y = CoO, z = P
₂ O ₅ ) and x + y + z = 1.000.

The reasons for setting the composition of the composite oxide as described above are as follows. That is, the lower limit of the composition of the blue colored film composed of the composite oxide of silicon oxide, cobalt oxide and phosphorous oxide is 0.804 mol fraction of silicon oxide, 0.194 mol fraction of cobalt oxide and 0.002 mol fraction of phosphorous oxide. This is because, as the concentration of cobalt oxide is further reduced, the degree of coloring of blue decreases, and the film thickness must be further increased in order to achieve a desired color temperature. . However, the lower limit setting is hardly affected by the concentration of phosphor oxide. The upper limit is composed of 0.086 mole fraction of silicon oxide, 0.623 mole fraction of cobalt oxide, and 0.291 mole fraction of phosphorous oxide. The color changes from dark brown to black brown as the color goes, and the color changes from blue. Therefore, by defining the composition of the composite oxide constituting the blue colored film as described above, a blue colored film having desired characteristics can be easily formed with high accuracy.

[0007]

However, a halogen bulb using such a color temperature conversion film made of a blue colored film emits white light with a higher pure color temperature, but is left in a high-temperature and high-humidity environment. In this case, it was found that the color temperature conversion film formed on the surface of the bulb peeled off from the heat-resistant and light-transmissive substrate constituting the bulb.

The present invention has been made in order to solve the above-mentioned problems in the previously proposed halogen bulb, and has been made to be a heat-resistant bulb constituting a bulb even in a high-temperature and high-humidity environment (temperature 70 ° C. or more and humidity 60 ° C. or more) It is an object of the present invention to provide a halogen bulb provided with a color temperature conversion film that emits high-purity white light without peeling from a light-transmitting substrate.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 is to provide at least one layer of oxidation on the outer surface of a halogen lamp bulb made of a heat-resistant translucent substrate having a filament inside. A high-color-type color temperature conversion film exhibiting a blue color composed of a composite oxide of silicon, cobalt oxide and phosphorous oxide is applied and formed. A halogen lamp is formed by forming at least one protective film made of a material. According to a second aspect of the present invention, in the halogen lamp according to the first aspect, the protective film made of a composite oxide of silicon oxide and phosphorous has a phosphorous concentration of 20% by weight or less based on the total oxide concentration. Of a composite oxide having the following composition:

As described above, at least one protective film made of silicon oxide or a composite oxide of silicon oxide and phosphorus oxide is formed on the high color temperature conversion film formed on the outer surface of the halogen bulb. Thereby, it is possible to effectively prevent the high-color type color temperature conversion film from peeling off from the outer surface of the bulb under a high-temperature and high-humidity environment. Here, the reason why the formation of such a protective film prevents the high color type color temperature conversion film from being peeled from the outer surface of the bulb will be described. Phosphorus oxide, which is an important substance for keeping the color tone of the high color temperature conversion film exhibiting blue color used in the present invention, is generally characterized by high hygroscopicity. In addition, an oxide thin film formed by a general sol-gel method, a coating thermal decomposition method, or the like tends to be porous having a large number of fine pores. Therefore, in a high-color-type color temperature conversion film containing a phosphor produced by the same method, in a high-temperature and high-humidity environment, moisture is taken in by a highly hygroscopic phosphor in the porous film, and the film itself is removed. Swells, and the stress changes in the membrane itself cause distortion in the valve body and membrane,
It is considered that peeling occurs.

Therefore, the inventor of the present invention has conceived of providing a protective film and filling the fine pores on the surface of the high-color-type color temperature conversion film formed on the valve base to prevent the intake of moisture. However, a low-refractive-index substance must be used as a protective film in order to prevent color turbidity with a high-color-type color temperature conversion film exhibiting blue, and hard glass is used as a halogen bulb. Therefore, there is a condition that the material must be easily vitrified at a low temperature, and as a result satisfying those conditions, a protective film made of silicon oxide or a composite oxide of silicon oxide and phosphorous oxide is appropriate. As a result, an experiment was carried out, and it was confirmed that the protective film had an effective peeling prevention function. Therefore, the protective film having the above-described configuration was used.

A protective film made of a composite oxide of a highly hygroscopic phosphor oxide and a silicon oxide also has a function of preventing peeling. The protective film made of this composite oxide is a high color type color temperature converter containing cobalt oxide. It has a higher thermal decomposition rate than the film and a higher tendency to densify, and silicon oxide and phosphorous oxide are network-forming oxides that can themselves form glass, but the oxides usually contained in large amounts in high color type color temperature conversion films Since cobalt is not a network-forming oxide, it is considered that the protective film made of only the network-forming oxide is more densified, thereby effectively preventing the incorporation of moisture and thereby preventing peeling. .

Next, the reason for setting the concentration of the phosphorus oxide in the composite oxide constituting the protective film as defined in claim 2 is as follows. The concentration of the phosphorus oxide in the composite oxide is represented by the following equation. Phosphorus oxide concentration (% by weight) = [P ₂ O ₅ / (SiO ₂ + P ₂
O ₅ )] × 100 The upper limit of the concentration of the phosphor in the composite oxide of silicon oxide and the phosphor is set to 20% by weight.
This is because if the concentration of the phosphoric acid is increased beyond the above range, the colorless and transparent protective film takes on a blackish hue and is colored. This coloring greatly affects the luminous flux maintenance rate. Therefore,
By defining the composition of the composite oxide composed of silicon oxide and phosphorous oxide, the color temperature conversion film having the desired characteristics can be peeled off in a high-temperature and high-humidity environment without coloring. Can be prevented.

[0014]

Next, an embodiment will be described. FIG. 1 is a sectional view showing an embodiment of a halogen bulb according to the present invention. FIG. 2 is a high-color-type color temperature conversion film having a blue color formed on the outer surface of the bulb and a protective film formed thereon. It is a typical sectional view which expands and shows a film. The halogen bulb of this embodiment is one in which the present invention is applied to a lamp used as a headlight of an automobile or the like, and, like the conventional example, is heat-resistant and transparent such as alumina silicate hard glass or quartz glass. A glass bulb 1 and two filaments 2a, 2 in the glass bulb 1 parallel to its central axis.
b is provided. The upper subfilament 2a is provided with a reflecting mirror 4 connected to a lead wire 3 in order to prevent light from shining on the oncoming vehicle side, and both ends of the filament 2a are connected to one end of the reflecting mirror 4 by a lead. Connected to line 5. Both ends of the main filament 2b are connected to lead wires 3 and 6, respectively. Lead wire 3,
5 and 6 are integrated by a bridge glass 7. On the outer surface of the glass bulb 1, a high color type color temperature conversion film 8 exhibiting blue color and a protective film 9 provided thereon are formed, and a base 10 is attached to an end of the glass bulb 1. Have been. A light-shielding film 11 is formed on the outer surface of the top of the glass bulb 1.

Next, a high color type color temperature conversion film 8 exhibiting blue color
And the configuration of the protective film 9 will be described. FIG. 2 is an enlarged schematic cross-sectional view showing the configuration of the laminated portion of the high-color type color temperature conversion film 8 and the protective film 9.
Is formed by laminating at least one or more layers of a blue colored film layer 81 made of a composite oxide of silicon oxide, cobalt oxide and phosphorous oxide, and further comprising at least one layer of silicon oxide or silicon oxide. The protective film 9 is made of a composite oxide of phosphor oxide. Then, for example, a laminated film composed of a single protective film 9 and a high-color-type color temperature conversion film 8 composed of ten blue colored film layers 81 has a spectral transmittance characteristic as shown in FIG. I have. As can be seen from the above-mentioned spectral transmittance characteristics, the laminated film of the protective film 9 and the high-color-type color temperature conversion film 8 configured as described above is not affected by the protective film 9 and has a wavelength of about 400 nm. Transmission, 600nm
The light having a wavelength centered on is presenting a bluish-violet color due to absorption by the coordination of Co ²⁺ ions. And about 380
Violet to blue visible region around ~ 400 nm and about 700 ~ 780
The transmittance characteristic in the red visible region near nm does not become flat and wavy, and therefore does not cause large reflection ripple, so it has the function of not feeling color unevenness caused by mixing with interference colors. It is a high-color type color temperature conversion film, and has a function of hardly causing a color tone change due to a difference in incident angle like an optical thin film because it is a blue colored film.

Next, an agent for forming a high color type color temperature conversion film comprising a composite oxide of silicon oxide, cobalt oxide and phosphorous oxide, an agent for forming silicon oxide constituting a protective film, and an agent for forming silicon oxide and phosphorous oxide The complex oxide forming agent will be described. (1) Color Temperature Conversion Film Forming Agent Consisting of Silicon Oxide-Cobalt Oxide-Phosphorus Complex Oxide First, a solvent in which an alkoxide of cobalt is dissolved, for example, benzene or the like is prepared. This benzene or the like is sufficiently dehydrated. Next, using this benzene solution or the like, cobalt alkoxide, for example, diisopropoxy cobalt Co (OiC ₃ H ₇ ) ₂ , and silicon alkoxide, for example, tetraethoxy silicate Si (OC ₂ H ₅ ) ₄ at a predetermined ratio. After dissolving for several hours while flowing dry nitrogen and mixing well, a predetermined amount of dehydrated ethanol is added. Then, an ethanol solution containing a predetermined amount of pure water is slowly and carefully added so as not to cause precipitation, and a hydrolysis reaction is performed. Further, in order to prevent gelation due to this reaction, acetylacetone (C ₅ H
₈ O ₂ ), ethyl acetoacetate (C ₆ H ₁₀ O ₃ ), etc. are added, and the mixture is further reacted for several hours. Then, benzene, ethanol, etc. are taken out by distillation under reduced pressure. After allowing the reaction product to stand for a while, an ethanol solution in which a predetermined amount of a phosphorus compound such as diphosphorus pentoxide or isopropyl acid phosphate is dissolved is added. Furthermore,
An organic solvent such as ethanol or ethyl acetate is added to adjust the concentration and viscosity of the solution to predetermined values. (2) Protective film forming agent composed of silicon oxide Organosilicon compound, for example, tetraethoxysilicate Si
(OC ₂ H ₅ ) ₄ is prepared. A predetermined amount of ethanol and pure water are added to carry out a hydrolysis reaction, and further, an organic solvent such as ethanol and ethyl acetate is added to adjust the concentration and viscosity of the solution to predetermined values. (3) Protective film forming agent composed of a composite oxide of silicon oxide-phosphorus oxide An organosilicon compound, for example, tetraethoxysilicate Si
(OC ₂ H ₅ ) ₄ is prepared. After a predetermined amount of ethanol and pure water are added to carry out a hydrolysis reaction, a predetermined amount of an ethanol solution in which a phosphorus compound such as diphosphorus pentoxide or isopropyl acid phosphate is dissolved is added, and an organic solution such as ethanol or ethyl acetate is further added. The solvent is added to adjust the concentration and viscosity of the solution to predetermined values.

Next, a method for forming a high-color-type color temperature conversion film exhibiting a blue color protected by a protective film so as not to be peeled off in a high-temperature and high-humidity environment using each of the above forming agents will be described. First, the bulb 1 of a halogen bulb is immersed in a mixed oxide forming agent of silicon oxide-cobalt oxide-phosphorus oxide, pulled up at a constant speed, dried, and then heat-treated in an atmosphere at about 400 to 700 ° C. for several minutes. A first blue colored film layer 81 is formed on the outer surface of the bulb 1. Thereafter, this operation is simply repeated to stack the blue colored film layers, thereby forming the high-color-type color temperature conversion film 8 exhibiting the desired color temperature of blue.

Next, the bulb 1 having the high color type color temperature conversion film 8 formed thereon is replaced with a protective film forming agent made of silicon oxide or
After immersing in a protective film forming agent composed of a silicon oxide-phosphorus oxide composite oxide, pulling up at a constant speed, and drying, it is similarly heat-treated in the air at about 400 to 700 ° C. for several minutes to form a protective film 9. I do. Then, the protective film 9 which does not peel off from the bulb 1 even when left in a high-temperature and high-humidity environment by this simple operation.
The color temperature conversion film 8 protected by the above can be obtained.

As described above, the present invention provides a high-color-type color temperature conversion film exhibiting blue color on the outer surface of the bulb and then applying a protective film made of silicon oxide or a composite oxide of silicon oxide and phosphorus oxide. The halogen bulb according to the above, and the halogen bulb of the comparative example in which only the previously proposed high-color type color temperature conversion film exhibiting blue was applied, left in a high-temperature and high-humidity environment, and the color temperature conversion film was peeled off from the bulb base. Will be described.

As an example, an H4 type halogen bulb (60/55 W, 1
Silicon oxide with a total oxide concentration of 7% by weight for each bulb of an H3 type halogen bulb for automobiles (55W, 13.2V, commonly rated 12V) using quartz glass as a bulb base (3.2V, generally 12V rated) Using a color temperature conversion film forming agent comprising a mixed oxide of -cobalt oxide-phosphorus oxide, each blue colored film layer is formed at a pulling rate of 6 mm / s at a firing temperature and time of 570 ° C for 4 minutes. After providing a color temperature conversion film composed of a 10-layer film and a 17-layer film, a protective film forming agent composed of silicon oxide having an oxide concentration of 3.5% by weight, and 3.92 to 4.3
Weight percent of a protective film-forming agent composed of a composite oxide of silicon oxide and phosphorus oxide was added at 4 mm / s, 6 mm / s, and 8 mm, respectively.
/ S at each pulling rate of 570 ° C., and a baking temperature and time of 570 ° C. for 4 minutes to form a one-layer and two-layer protective film to produce a halogen bulb according to the present invention. Table 1 shows the results when the protective film was left, and Table 2 shows a comparative example in which the protective film was not formed. In Tables 1 and 2,
In the column of presence / absence of peeling, a mark “○” indicates that peeling does not occur even after elapse of 400 hours, and a mark “X” indicates that peeling occurs in about 2 hours.

[0021]

[Table 1]

[0022]

[Table 2]

Next, the composition of the color temperature conversion film is the same as that shown in Table 1, except that only the composition of the protective film is changed to form a similar type of halogen bulb having a color temperature conversion film in which a protective film is laminated. Table 3 shows the results of the peeling test.

[0024]

[Table 3]

Next, the same types of halogen lamps as those shown in Tables 1 and 2 except that the composition of the color temperature conversion film was changed were prepared and tested. Table 4 shows the results of the present invention. Table 5 shows comparative examples.

[0026]

[Table 4]

[0027]

[Table 5]

From the above test results, it was found that a halogen lamp provided with a color temperature conversion film exhibiting a blue color by a composite oxide of silicon oxide, cobalt oxide and phosphorous oxide was subjected to silicon oxide or a composite oxide of silicon oxide and phosphorous oxide. It has been confirmed that by laminating a protective film made of a material, a color temperature conversion film that does not occur conventionally and does not peel off even when left in a high-temperature and high-humidity environment can be produced.

In the above trial production test, the protective film made of silicon oxide or a composite oxide of silicon oxide and phosphorous oxide was 1
The measurement results for the case where two or more layers are provided are shown. Needless to say, the same effect can be obtained with other pulling speeds and more layers. However, the increase in the number of protective films causes peeling of the color temperature conversion film from the valve substrate,
It is best to keep it to about one layer because it leads to an increase in cost. The starting materials of silicon and phosphorus for forming the protective film are not limited to those described in the above embodiment.

[0030]

According to the first aspect of the present invention, as described above with reference to the embodiments, at least one or more layers of a composite oxide of silicon oxide, cobalt oxide and phosphorous oxide exhibiting a blue color. A protective film made of at least one layer of silicon oxide or a composite oxide of silicon oxide and phosphorous oxide is formed on the temperature conversion film, so that it is left in a high-temperature and high-humidity environment without any complicated work. However, it is possible to realize a halogen bulb that emits high-purity white light for a long period without causing peeling of the color temperature conversion film. According to the second aspect of the invention, a protective film made of a silicon oxide-phosphorus oxide composite oxide that does not blacken can be formed, and the color temperature conversion film does not peel even when left in a high-temperature and high-humidity environment. A halogen bulb that emits white light with higher purity can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a halogen lamp according to the present invention.

FIG. 2 is an enlarged schematic cross-sectional view showing a laminated portion of a color temperature conversion film and a protective film in the embodiment shown in FIG.

FIG. 3 is a view showing a spectral transmittance characteristic of a color temperature conversion film provided with a protective film shown in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass bulb 2a Subfilament 2b Main filament 3,5,6 Lead wire 4 Reflector 7 Bridge glass 8 Color temperature conversion film 81 Blue coloring film layer 9 Protective film 10 Base 11 Light shielding film

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[Procedure amendment]

[Submission date] July 18, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

The present invention has been made in order to solve the above-mentioned problems in the previously proposed halogen bulb, and has been made in order to form a bulb under a high-temperature and high-humidity environment (at a temperature of 70 ° C. or more and a humidity of 60 % or more). It is an object of the present invention to provide a halogen bulb provided with a color temperature conversion film that emits high-purity white light without peeling from a light-transmitting substrate.

Claims (2)

[Claims] 1. A high-color type color having a blue color composed of at least one layer of a composite oxide of silicon oxide, cobalt oxide and phosphorous oxide on the outer surface of a halogen bulb composed of a heat-resistant and translucent substrate having a filament inside. A halogen lamp comprising a temperature conversion film formed by coating, and at least one protective film made of silicon oxide or a composite oxide of silicon oxide and phosphorus oxide formed on the high color type color temperature conversion film. . 2. The protective film comprising a composite oxide of silicon oxide and phosphorus oxide is a film comprising a composite oxide having a concentration of phosphorus oxide of 20% by weight or less based on the total oxide concentration. The halogen lamp according to claim 1, wherein