JP2000100385A - High-pressure discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain change of an emission spectrum due to the reduction of dysprosium iodide, even after a long-time use of a high pressure discharge lamp. SOLUTION: This high-pressure discharge lamp has a ceramic discharge tube 1 filled with an ionized luminescent material and starting gases, and an electrode device 2 laid in an internal space. An open part 1a is formed on the end of the ceramic discharge tube 1, and this open part 1a is sealed airtightly using at least a metalized layer 6. In this case, the metalized layer 6 contains a metallic component and a glass component containing dysprosium oxide and/or molybdenum oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure discharge lamp using a ceramic discharge tube.

[0002]

2. Description of the Related Art In such a high-pressure discharge lamp, a plugging material (usually called a ceramic plug) is inserted inside both ends of a ceramic discharge tube, and each end is closed. A through hole is provided in the material, and a metal current conductor to which a predetermined electrode system is fixed is inserted through the through hole. An ionized luminescent substance is sealed in the internal space of the ceramic discharge tube. As such a high-pressure discharge lamp, a high-pressure sodium emission lamp and a metal halide lamp are known, and particularly, the metal halide lamp has good color rendering properties. The use of ceramic as the material of the discharge tube has made it possible to use it at high temperatures.

[0003] In such a discharge lamp, it is necessary to hermetically seal the gap between the end of the ceramic discharge tube and the electrode device holding material. The body of the ceramic discharge tube is in the form of a tube or barrel having both ends narrowed, or a straight tube. The ceramic discharge tube is made of, for example, an alumina sintered body.

[0004]

Various light-emitting substances are present in the internal space of the ceramic discharge tube. Since the emission spectra of the respective light-emitting substances are different from each other, the emission spectrum of the high-pressure discharge lamp is made to resemble natural light as a whole by adjusting the proportion of each light-emitting substance. Particularly when used for a long period of time, dysprosium iodide in the internal space tends to react with the ceramic component in the glass sealing material and decrease. Since dysprosium has a broad spectrum in a wide wavelength range, when dysprosium iodide in the internal space is reduced, light emission is darkened as a whole.

As described above, the ceramic discharge tube is filled with a metal halide having high corrosiveness. Although sealing is performed with a glass sealing material, there is a problem that glass is susceptible to corrosion. For this reason, the present inventor has developed a technique for obtaining high corrosion resistance by sealing the gap between the closing member at the end of the ceramic discharge tube and the conductive member with a metallized layer,
It is disclosed in Japanese Patent Application No. 9-32240. Further, it is required to stabilize the emission spectrum by improving the wettability between the metallized layer and the conductive member and the ceramic discharge tube, and further improving the airtightness after the heat cycle.

An object of the present invention is to provide a high-pressure discharge lamp having a ceramic discharge tube in which an internal space is filled with an ionized luminescent substance and a starting gas, and an electrode device provided in the internal space. The purpose of the present invention is to suppress a change in emission spectrum due to a decrease in dysprosium iodide even after long-term use.

Another object of the present invention is to make it possible to maintain a good airtightness even when a lighting-off cycle of a high pressure discharge lamp is repeated, thereby stabilizing a light emitting state.

[0008]

SUMMARY OF THE INVENTION The present invention is a high pressure discharge lamp comprising a ceramic discharge tube having an interior space filled with an ionized luminescent material and a starting gas and an electrode device provided in the interior space. An opening portion is provided in the ceramic discharge tube, and the opening portion is hermetically sealed using at least a metallization layer, and the metallization layer includes a metal component and a glass component containing at least dysprosium oxide. It is characterized by containing.

The present invention also relates to a high-pressure discharge lamp having an internal space filled with an ionized luminescent substance and a starting gas, and a high-pressure discharge lamp including an electrode device provided in the internal space. Is provided with an opening portion, this opening portion is hermetically sealed by at least a metallized layer, this metallized layer,
It is characterized by containing a metal component and a glass component containing at least molybdenum oxide.

The present inventor has proposed that the ceramic discharge tube or the plugging material and the conductive member be sealed with a metallized layer and that at least dysprosium oxide be added as a glass component to the metallized layer in addition to the metal component. I arrived and did an experiment. As a result, it was found that dysprosium oxide in the metallized layer gradually changed into dysprosium iodide over a long period of time and leached into the luminescent material, thereby suppressing deterioration of the luminescent spectrum of the luminescent material. The invention has been reached.

[0011] The reason why such an effect is obtained is not clear. When observing the microstructure of the metallized layer, a metal component having corrosion resistance to the luminescent substance forms a kind of matrix, and the glass component is dispersed in the matrix, and dysprosium oxide is mixed with other glass components in this glass component. Eutectic. As a result, the corrosion of the metallized layer proceeds at an extremely slow rate, and in the course of this slow corrosion process, dysprosium oxide is gradually released into the internal space from the dispersed phase of the glass component dispersed in the matrix. Is considered to be converted to dysprosium iodide through a more complicated reaction.

Japanese Patent Application Laid-Open No. 6-196131 discloses that the opening at the end of the ceramic discharge tube is sealed with a glass sealing material, and that dysprosium oxide is contained in the sealing material. Have been. However, in such a configuration, since erosion of the glass sealing material proceeds early, dysprosium oxide cannot be slowly supplied to the inside of the discharge tube for a long period of time. In addition, when a large amount of dysprosium oxide is supplied to the inner space of the discharge tube together with other corrosive substances, a conversion reaction of dysprosium oxide to dysprosium iodide does not effectively proceed. Details of such reactions are not clear to those skilled in the art, and thus, according to the present invention,
It could not be predicted that dysprosium iodide could be slowly supplied to the bottom space of the discharge tube over a long period of time.

Further, the present inventor has found that by adding molybdenum oxide to the above-mentioned metallized layer, the hermeticity of the metallized layer after a thermal cycle is further improved. This is probably because the addition of molybdenum oxide to the metallized layer improved the wettability of the metallized phase to the conductive member.

When the closing member and the conductive member are joined via the metallized layer of the present invention, the conductive member is connected to the end of the closing member opposite to the internal space via the metallized layer. It is particularly preferred to have a tight and airtight joint, which minimizes residual stress on the closure. When joining the ceramic discharge tube and the conductive member via the metallized layer of the present invention, the conductive member is hermetically sealed via the metallized layer to the end opposite to the internal space of the discharge tube. Joining is particularly preferred, which minimizes residual stress on the closure. As a result, in particular, even if the cycle of turning on and off is repeated many times, the reliability for airtightness is improved. Further, since the metallized layer is provided at the end, that is, provided at a position away from corrosive substances in the internal space of the discharge tube, the supply speed of dysprosium oxide to the internal space is further reduced, The release period is longer. The following mainly describes this aspect of the present invention.

If the plugging material is eliminated and the conductive member is directly and airtightly joined to the end of the ceramic discharge tube via the metallized layer, it is extremely effective especially for downsizing the high pressure discharge lamp. Was. That is, the size of the high-pressure discharge lamp in the width direction is limited by the size of the end portion. However, since the plugging material is inserted inside the end of the ceramic discharge tube, it is difficult to reduce the size of the ceramic discharge tube in the width direction to a certain extent or more. It was difficult to make it smaller. As a result, specifically, when the output was suppressed to a level of 25 W or less, the luminous efficiency of the space inside the ceramic discharge tube became extremely low. According to the present invention, since such miniaturization is possible, it is epoch-making in that a high-power discharge lamp having a small output of 25 W or less can be provided as a commercial product.

The conductive member may be an electrode device holding material to which the electrode device is directly attached, or may be a tubular member for inserting the electrode device holding material to which the electrode device is directly attached. There is no particular limitation. As the latter example, the technique described in JP-A-6-318435 can be exemplified.

As the material of the conductive member, various high melting point metals and conductive ceramics can be used, but from the viewpoint of conductivity, the high melting point metal is more preferable. As such a high melting point metal, one or more metals selected from the group consisting of molybdenum, tungsten, rhenium, niobium, tantalum, and alloys thereof are more preferable.

Of these, the coefficient of thermal expansion of niobium and tantalum almost matches the coefficient of thermal expansion of ceramics constituting a ceramic discharge tube, particularly alumina ceramics. However, it is known that these metals are easily corroded by metal halides. I have. Therefore, in order to extend the life of the conductive member, it is preferable that the conductive member be formed of a metal selected from the group consisting of molybdenum, tungsten, rhenium, and alloys thereof. However,
Metals with high corrosion resistance to these metal halides
Generally, the coefficient of thermal expansion is small. For example, the coefficient of thermal expansion of alumina ceramics is 8 × 10 ⁻⁶ K ⁻¹ , the coefficient of thermal expansion of molybdenum is 6 × 10 ⁻⁶ K ⁻¹ , and tungsten,
Rhenium has a coefficient of thermal expansion of 6 × 10 ⁻⁶ K ⁻¹ or less.

When molybdenum is used as the material of the conductive member, La ₂ O ₃ and C
at least one kind of eO ₂ is 0.1% by weight or more in total
It is particularly preferred that the content is 2.0% by weight.

The metal component constituting the metallized layer is preferably a metal selected from the group consisting of molybdenum, tungsten, rhenium, niobium, tantalum and alloys thereof. In particular, in order to further improve the corrosion resistance of the metallized layer to halogen, a metal selected from the group consisting of molybdenum, tungsten, rhenium, and an alloy thereof is particularly preferable.

In this metallized layer, other than dysprosium oxide and molybdenum oxide, Al ₂ O ₃ , Si
It is preferable to contain one or more glass components selected from the group consisting of O ₂ , Y ₂ O ₃ , B ₂ O ₃ and mullite. In particular, it preferably contains Al ₂ O ₃ and SiO ₂ . Further, from the viewpoint of wettability, it is preferable to contain the main component of the ceramic member or the plugging material. Here, the main component refers to a ceramic component occupying 70% by weight or more of the ceramic member. This is particularly preferably alumina.

Assuming that the total glass component contained in the metallized layer is 100% by weight, the ratio of each component is preferably as follows. That is, when Dy ₂ O ₃ is added, the amount added is 30% by weight for achieving the effects of the present invention.
It is more preferably at least 50% by weight. Further, from the viewpoint of securing an appropriate glass softening point, 7
It is preferably at most 0% by weight, more preferably at most 65% by weight.

The amount of molybdenum oxide to be added is preferably 1% by weight or more, more preferably 3% by weight or more, for achieving the effects of the present invention. Further, from the viewpoint of reducing bubbles in the glass component, the content is preferably 10% by weight or less, more preferably 8% by weight or less.

Al_TwoO_ThreeIs 10% -30% by weight
It is preferred that the_Two, Y_TwoO
_ThreeAnd an appropriate network structure. SiO _TwoIs 1
Preferably, it is 5% by weight to 40% by weight.
Thus, an appropriate viscosity at the time of melting is obtained. Y_TwoO_ThreeIs 0% by weight
-40% by weight.
O_Two, Al_TwoO_ThreeAnd a proper network structure is obtained
You. B_TwoO_ThreeIs preferably 0% -5% by weight
Thus, a suitable melting point lowering effect is obtained. M
Light is preferably 50-100% by weight,
Thereby, Al _TwoO_ThreeOr SiO_TwoAlone
At a lower temperature than when_TwoO_Three-SiO_TwoAverage
One phase is obtained.

Particularly preferred combinations are shown below. (A) Alumina 15-25 wt% Silica 15-25 wt% Dysprosium oxide 45-65 wt% Molybdenum oxide 0 wt% -5 wt% (b) Mullite 20-40 wt% Dysprosium oxide 0-50 wt% Molybdenum oxide 0 % By weight-10% by weight

The content ratio of the metal component and the ceramic component in the metallized layer is 30/70 volume% to 70/70 volume%.
It is preferred to be 30% by volume. Further, the thickness of the metallized layer is preferably 10 to 200 μm.

Furthermore, by adding 20% by volume or less of metallic silicon to the material for metallization before firing, it reacts with the oxygen of water vapor in the firing atmosphere to neutralize the metal component during metallization with this oxygen. To improve the airtightness of the metallized structure.

In a preferred embodiment of the present invention, when forming the metallized layer, the conductive member is provided between the end of the fired body of the plugging material or the end of the fired body of the ceramic discharge tube. A layered metallizing material is interposed. The metallizing material is a material that forms a metallized layer after firing, and specifically includes the above-described metal component and glass component (or ceramic component).

The layered metallizing material can be produced preferably by the following method. (1) A metallized paste is applied and printed on the end of the object to be fired of the plugging material or the end of the object to be fired of the ceramic discharge tube, and / or the metalized paste is applied and printed on the outer surface of the conductive member. I do.

It is preferable to add a binder having excellent thermal decomposability to the metallized paste for forming the metallized layer. Examples of such a binder include ethyl cellulose and an acrylic binder.

(2) A cylindrical molded body made of a metallizing material is inserted between each of the above-mentioned fired bodies and the conductive member,
Intervene. This cylindrical molded body is preferably molded by a press molding method because it requires structural strength to withstand handling.

In producing the cylindrical molded body, a binder is added to the metal component for the metallized layer and, if necessary, the ceramic component. As the binder, a binder that is easily dissociated by heat and is easy to press is preferable, and polyvinyl alcohol (PV)
A) and an acrylic binder are preferred. A binder and a small amount of a solvent are added to the components for the metallized layer, and the mixture is granulated by a spray drier or the like to produce granules.
Alternatively, granules can be formed by adding a binder and a small amount of a solvent to the above components for the metallized layer, kneading, drying and pulverizing. This granule is 2-3 ton / cm ²
Press molding at a pressure of 5 to obtain a cylindrical molded body. At the time of assembling, the cylindrical molded body is fitted to the conductive member, and each of the above-mentioned fired bodies is fitted to the outside of the cylindrical molded body. In addition,
The firing conditions for the cylindrical molded body are the same as the firing conditions for the metallized paste.

(3) A sheet-shaped formed body made of a metallizing material is interposed between each of the above-mentioned fired bodies and the conductive member.

In order to prepare this sheet-like molded body, a binder such as an acrylic binder or ethyl cellulose is added to the metal component for the metallized layer and, if necessary, the ceramic component, and butyl carbitol acetate ( Using a solvent such as BCA), a sheet-like molded body is obtained by, for example, a doctor blade method.

As the material of the plugging material, the same material as that of the ceramic discharge tube is used. As a result, almost no residual stress is generated between the ceramic discharge tube and the plugging material in the direction of the central axis of the ceramic discharge tube. Here, the same kind of material refers to a material having a common base ceramic, and the added components may be different.

When the conductive member is made of a metal, it is preferable that the metal component in the metallized layer and the conductive member contain a common material, whereby the bonding strength between them is further improved.

The sealing method as described above can be adopted at both ends of the ceramic discharge tube, but it is necessary to inject an ionized luminescent substance through the inside of the conductive member at one end. Therefore, it is necessary to make the conductive member tubular. At the other end, conductive members having various shapes such as a rod shape and a tubular shape can be adopted.

The shape of the ceramic discharge tube is generally
It can be tubular, cylindrical, barrel-shaped, or the like. When the electrode device holding material is tubular, and the ionized luminescent substance is sealed inside the discharge tube through the electrode device holding material, after the sealing, the electrode device holding material is laser welded or TIG.
Closed by welding.

In the case of a metal halide high-pressure discharge lamp, an inert gas such as argon and a metal halide are sealed in the internal space of the ceramic discharge tube, and mercury is further sealed if necessary.

In the present invention, the conductive member is joined to the end of the closing member or the end of the ceramic discharge tube. (1) On the end face of the plugging material or the end face of the ceramic discharge tube,
Join the ends of the conductive member. In this case, in particular, the stress applied to the metallized layer by thermal cycling is significantly reduced, and in this sense the life of the high-pressure discharge lamp is further extended.

(2) Insert the end of the conductive member into the through hole of the plugging material or into the through hole of the ceramic discharge tube;
The outer peripheral surface of the end of the conductive member is joined to the inner peripheral surface of the end of the closing member or the inner peripheral surface of the end of the ceramic discharge tube. In this case, especially when the internal pressure of the ceramic discharge tube is high, durability against this pressure can be imparted.

(3) In (2), a recess is further provided on the inner peripheral surface of the end of the closing member, and the end of the conductive member is accommodated in the recess. And the closing material are hermetically bonded via the metallized layer. Similarly, a recess is provided on the inner peripheral surface at the end of the opening of the ceramic discharge tube, the end of the conductive member is accommodated in the recess, and the end of the conductive member and the ceramic discharge tube are accommodated in the recess. Is hermetically bonded via a metallized layer.

By adopting this structure, even if the pressure in the internal space of the ceramic discharge tube becomes, for example, 10 atmospheres or more, the metallized layer extends vertically and horizontally in the longitudinal direction of the ceramic discharge tube. , The durability against gas pressure is extremely high, so that the reliability is high, and the effect of relaxing the stress due to the thermal cycle is also high.

Hereinafter, more specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1A is an enlarged sectional view showing the periphery of the opening 1a of the ceramic discharge tube 1. FIG.
FIG. 1B further shows details of a preferred example of the joining portion.
FIG.

The inner surface 1b of the opening 1a of the ceramic discharge tube 1 extends straight when viewed in the direction of the central axis of the ceramic discharge tube. A closing member 4 is provided inside the opening 1a.
Is inserted. The discharge tube 1 and the plugging material 4 are formed of the same type of ceramic, preferably alumina ceramic, and the interface between them has almost disappeared in the firing step. Reference numeral 4c denotes an outer surface of the closing member 4.

On the end surface 4b side of the inner peripheral surface 4a of the closing member 4,
A recess or step 9 is provided. The end 7 a of the conductive member 7 is accommodated in the recess 9. In this example,
The conductive member 7 has a tubular shape, and is provided with an opening for sealing after sealing the starting gas and the ionized luminescent substance.

A recess 9 is provided between the closing member 4 and the conductive member 7.
The metallized layer 6 is interposed in the inside, the two are joined by the metallized layer 6, and the airtightness is maintained. 7b is an outer surface of the conductive member 7, and 7c is an inner surface thereof. The inner space of the conductive member 7 communicates with the inner space 3 of the discharge tube 1 via the through hole of the closing member 4.

The metallized layer 6 is formed as shown in FIG.
It is particularly preferable to be constituted by a laminate of two metallized layers 10 and 11. However, here, the metallized layer 11 on the conductive member 7 side has a relatively higher metal ratio, and the metallized layer 10 on the closing member 4 side has a lower metal ratio than the metallized layer 11. The stress caused by the difference in thermal expansion between the closing member 4 and the conductive member 7 can be further reduced. The metallized layer 6 is further divided into three or more layers, and three or more metallized layers are sequentially arranged from the plugging material 4 or the ceramic discharge tube side to the conductive member side, and the ratio of metal in each metallized layer is determined as follows. It can be increased stepwise from the discharge tube side toward the conductive member side.

In this embodiment, a metallized layer 5 is further formed along the inner peripheral surface 4a of the closing member 4, and the metallized layer 5 is formed.
The electrode device 2 is attached to the end on the side of the internal space 3.

The mounting method of the electrode device is not limited to the embodiment shown in FIG. For example, the electrode device can be attached as shown in FIGS. However, each component shown in FIG. 1 is denoted by the same reference numeral, and description thereof is omitted.

First, as shown in FIG. 2A, the conductive member 7 is joined to the closing member 4. Here, the electrode device is not installed in the internal space. Next, the electrode device 2 is mounted on a sealing member (preferably made of metal) 12, and the sealing member 12 and the electrode device 2 are inserted into the through holes of the internal space 3 and the closing member 4 as shown in FIG. Then, the sealing member 12 is joined to the inner peripheral surface 7c of the conductive member 7 by welding or the like,
The sealing portion 13 as shown in FIG. 2C is formed. Thus, the ionized luminescent material and the starting gas in the internal space 3 are sealed so as not to contact the outside air, and electric power can be supplied to the electrode device 2 through the sealing member 12.

In FIG. 3, the inner surface 1b of the opening portion 1a of the ceramic discharge tube 1 extends straight when viewed in the direction of the central axis of the ceramic discharge tube. Inner peripheral surface 1 of opening 1a
A concave portion or a step portion 19 is provided on the end 1d side of b. The end 7 a of the conductive member 7 is accommodated in the recess 19. A metallized layer 15 is interposed between the discharge tube 1 and the conductive member 7 in the concave portion 19, and the two are joined by the metallized layer 15 and airtightness is maintained. In addition, 14 is a metallized layer connected to the electrode device 2.

FIGS. 4 and 5 illustrate still another embodiment of the present invention. In FIG. 4, the end of the conductive member 7 faces the end face 4 b of the closing member 4 at a slight interval. A metallized layer 16 is interposed between the end face 4b and the end 7a of the conductive member 7, and the two are joined by the metallized layer 16 and airtightness is maintained.

In FIG. 5, the end of the conductive member 7 is opposed to the end face 1c of the discharge tube 1 at a slight interval. Between the end face 1c and the end 7a of the conductive member 7,
The metallized layer 16 is interposed, the two are joined by the metallized layer 16, and the airtightness is maintained.

The metallization layer 16 is composed of, for example, a laminate of two metallization layers 16a and 16b. However, the metallized layer 16b on the conductive member 7 side is
The ratio of metal is relatively high, and the closing material 4 or the discharge tube 1
The metallized layer 16a on the side has a lower metal ratio than the metallized layer 16b, so that the stress caused by the difference in thermal expansion between the plugging material 4 or the discharge tube 1 and the conductive member 7 is further reduced. can do.

In each of the embodiments described above, it is more preferable to further provide a ceramic fired layer between the metallized layers 6, 15, 16 and the ceramic discharge tube or plugging material. This aspect will be further described. FIG.
FIG. 2A is a cross-sectional view schematically showing an enlarged structure of a joint portion between the discharge tube 1 or the closing member 4 and the conductive member 7.

The microstructure of this sectional view is further enlarged to
This is schematically shown in FIG. C is a conductive member and has a substantially dense microstructure. B is a metallized layer. A
Is a discharge tube or a plugging material. In the process of forming this joint structure, the two are firmly joined by the diffusion of metal from the metallizing material to the conductive member, but the discharge tube or plugging material is already firmly press-formed, Are grown and the number of pores is small, and the movement and diffusion of the ceramic component hardly occur. In addition, there is an adverse effect when the metal component diffuses from the metallizing material into the discharge tube or the plugging material.

For this reason, as shown in FIG. 7A, it is particularly preferable to further form a ceramic fired layer 20 between the discharge tube 1 or the plugging material 4 and the metallized layers 6, 15, 16. This microstructure is enlarged and schematically shown in FIG.
Shown in

The metallized layer B is formed next to the conductive member C having a substantially fine microstructure. D is a ceramic fired layer. The ceramic component is easily diffused between the fired layer and the metallized layer, and the ceramic material is the same kind of material between the fired layer and the ceramic discharge tube or plugging material. Strong diffusion is likely to occur due to the diffusion of the components.

As described above, the ceramic component in the layered ceramic firing material is easily diffused into the ceramic discharge tube or the closing material, and the bonding strength between the two is further improved and stabilized, and the metallized layers 6 and 15 are further improved. , 16 to the discharge tube or the ceramic structure of the plugging material can be prevented from diffusing.

Here, in order to form the ceramic fired layer between the plugging material or the ceramic discharge tube and the metallized layer, a layered ceramic firing material is interposed here. The ceramic firing material refers to a material that forms a ceramic after firing, and specifically includes the ceramic component described above. The layered ceramic firing material can be preferably formed by the following method.

(1) A ceramic paste is applied and printed.

(2) A cylindrical molded body made of a ceramic firing material is inserted and interposed between the fired body of the plugging material or the fired body of the ceramic discharge tube and the layered metallizing material. This cylindrical molded body is preferably molded by a press molding method because it requires structural strength to withstand handling.

In producing this cylindrical molded body, a binder is added to the ceramic component. As the binder, a binder that is easily dissociated by heat and is easy to press is preferable, and polyvinyl alcohol (PV)
A) and an acrylic binder are preferred. A binder and some solvent are added to the ceramic component, and the mixture is granulated by a spray drier or the like to produce granules. Alternatively, granules can be formed by adding a binder and a small amount of a solvent to the ceramic component, kneading, drying, and pulverizing.
The granules are pressed at a pressure of 2-3 ton / cm ² ,
Obtain a cylindrical molded body.

(3) A sheet-shaped formed body made of a ceramic firing material is interposed between the firing object of the plugging material or the firing object of the ceramic discharge tube and the layered metallizing material.

In order to produce this sheet-like molded body, a binder such as an acrylic binder or ethyl cellulose is added to the ceramic component, and a solvent such as butyl carbitol acetate is used. To obtain a molded article.

Next, the most suitable process for manufacturing the high-pressure discharge lamp according to each embodiment of the present invention will be described. When joining the plugging material and the conductive member with a metallized layer, first, a material powder (preferably alumina powder) of the plugging material is molded to obtain a ring-shaped molded product of the plugging material. At this stage, the powder granulated by a spray drier or the like is
It is preferable to press-mold at a pressure of 000 to 3000 kgf / cm ² . The obtained molded body is preferably degreased and calcined to obtain a calcined body.

At this time, the degreasing treatment is preferably performed by heating at a temperature of 600 to 800 ° C., and the calcining treatment is preferably performed by heating at a temperature of 1200 to 1400 ° C. in a hydrogen reducing atmosphere. By this calcining treatment, a certain degree of strength is given to the molded body of the plugging material, paste leveling failure due to suction of a solvent when the metallizing material is brought into contact with the plugging material is prevented, and the handleability of the plugging material is improved. be able to. The recess can be formed, for example, by machining.

Next, a metallizing paste is applied to a predetermined portion of the plugging material to form a metallizing paste layer.
The calcined body is dried preferably at 90 to 120 ° C.

Next, the conductive member is opposed to a predetermined portion of the calcined body. This calcined body is pre-fired at a temperature of 1200 to 1600 ° C. in a reducing atmosphere having a dew point of 20 to 50 ° C. (firing step).

On the other hand, the body of the ceramic discharge tube is formed,
The molded body is degreased and calcined to obtain a calcined body of the ceramic discharge tube. On the end face of the obtained calcined body, a prefired body of the plugging material is inserted, set at a predetermined position, and fully fired at a temperature of 1600 to 1900 ° C under a reducing atmosphere at a dew point of -15 to 15 ° C. Thus, the high pressure discharge lamp of the present invention is obtained.

The metallizing paste can be printed on the conductive member without printing the metallizing paste on the closing material. Further, a ceramic paste made of the same material as the plugging material is applied to the surface of the plugging material to form a ceramic paste layer, and a metallizing paste can be applied thereon.

According to the above-described manufacturing process, the ceramic discharge tube shown in FIG. 4 was manufactured. However, the ceramic discharge tube and the plugging material were formed of alumina porcelain, and a molybdenum pipe was used as the conductive member. Also,
The metallized layer for joining the closing member and the conductive member was produced as follows. That is, the molybdenum powder was crushed to obtain a powder having a tap density of 3.9 g / cc. Ethyl cellulose was added as a binder to molybdenum powder, and glass powder was added to prepare a metallizing paste. The composition of the glass component added was 60% by weight of dysprosium oxide, 15% by weight of alumina, and 25% by weight of silica.

A heat cycle test was performed on the ceramic discharge tube. Specifically, it was held at room temperature for 15 minutes, then the temperature was raised to 850 ° C., held at 850 ° C. for 5 minutes, and then the temperature was lowered to room temperature as one cycle, and a thermal cycle of 500 cycles was performed. . Thereafter, it was measured the presence of a leak by a helium leak test, leak amount ^{10 - 1 0 atm · cc ·} sec
Was less than. Note that 850 ° C. is the temperature of the sealed portion during normal use.

Further, the high-pressure discharge lamp was set to 150 W
, And was continuously turned on for 3000 hours. The efficiency before the long-term lighting test was 90 Lm / W, and the efficiency after the long-term lighting test was 85 Lm / W, and almost no decrease was observed.

Further, a ceramic discharge tube shown in FIG. 4 was manufactured according to the above-described manufacturing process. However, the ceramic discharge tube and the plugging material were formed of alumina porcelain, and a molybdenum pipe was used as the conductive member. Further, the metallized layer for joining the closing member and the conductive member was produced as follows. That is, the molybdenum powder was crushed to obtain a powder having a tap density of 3.9 g / cc.
Ethyl cellulose was added as a binder to the molybdenum powder, and a glass powder was added to prepare a metallizing paste. The composition of the added glass component was 5% by weight of molybdenum oxide and 95% by weight of mullite.

A thermal cycle test was performed on the ceramic discharge tube. Specifically, a thermal cycle of holding at room temperature for 15 minutes, then increasing the temperature to 950 ° C., maintaining the temperature at 950 ° C. for 5 minutes, and then decreasing the temperature to room temperature was defined as one cycle, and a thermal cycle of 1000 cycles was performed . Thereafter, was measured the presence of a leak by a helium leak test, leak amount ^{10 - 1 0 atm · cc ·} se
c. Note that 850 ° C. is a normal use temperature, and 950 ° C. is an overload temperature. The durability against this means that the starting gas and the ionized luminescent substance can be safely held for a long time even when the starting gas and the ionized luminescent material are pressed into the discharge tube at a higher pressure than usual.

Next, when the ceramic discharge tube and the conductive member are directly joined to each other, first, the body of the ceramic discharge tube is formed, the formed body is degreased and calcined, and the calcined body of the ceramic discharge tube is formed. Get. A metallizing paste is applied to a predetermined portion of the obtained calcined body as described above. At this time, if necessary, a ceramic paste made of the same material as the calcined body is applied before the metallized paste. The calcined body is dried at 90 to 120 ° C. in the air. A conductive member is disposed at a predetermined position, fixed, and pre-fired at a temperature of 1200 to 1600 ° C. in a reducing atmosphere having a dew point of 20 to 50 ° C.
Then, under a reducing atmosphere with a dew point of -15 to 15 ° C, 170
Main firing is performed at a temperature of 0 to 1900 ° C. The preliminary firing and the main firing may be performed independently, but may be performed continuously when an atmosphere furnace having both reducing atmospheres can be used.

Alternatively, the calcined body is heated at 300 to 400 ° C. in air or in a nitrogen atmosphere to degrease it, assembled, and heated in a reducing atmosphere at a dew point of −15 to 15 ° C.
Main firing is performed at a temperature of 0 to 1900 ° C.

In the above-mentioned process, the metallizing paste (and the ceramic paste if necessary) is not applied to the body of the ceramic discharge tube, but the metallizing paste (and If necessary, a ceramic paste can be applied.

[0082]

As described above, according to the present invention, even after a high-pressure discharge lamp has been used for a long time, it is possible to suppress a change in the emission spectrum due to a decrease in dysprosium iodide, and to turn on and off the high-pressure discharge lamp. Even when the cycle is repeated, good airtightness can be maintained. Thus, the light emitting state can be stabilized for a long period of time.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing a joint structure of an end portion of a discharge tube according to an embodiment of the present invention, and FIG. 1B is a schematic cross-sectional view showing a preferred form of a metallized layer 6. FIG.

FIGS. 2A, 2B, and 2C illustrate an embodiment in which a sealing member 12 of an electrode device is joined to a conductive member using a joining structure as shown in FIG. FIG.

FIG. 3 is a cross-sectional view showing a joint structure of an end portion of a discharge tube according to another embodiment of the present invention, in which a conductive member is joined to a concave portion at an end portion of a discharge tube 1;

FIG. 4 is a sectional view showing a joint structure of an end portion of a discharge tube according to still another embodiment of the present invention, in which a conductive member is joined to an end surface 4b of a closing member 4.

FIG. 5 is a cross-sectional view showing a joining structure of a discharge tube end according to still another embodiment of the present invention, in which a conductive member is joined to an end face 1c of the discharge tube 1.

FIGS. 6A and 6B are cross-sectional views schematically showing a microstructure of a joint portion between a discharge tube or a plugging material, a metallized layer, and a conductive member.

FIGS. 7A and 7B are cross-sectional views schematically showing a microstructure of a joint portion between a discharge tube or a plugging material, a ceramic fired layer, a metallized layer, and a conductive member.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ceramic discharge tube, 1a opening part, 2 electrode device, 3 internal space, 4 closing member, 4a inner peripheral surface of closing member, 4b end surface of closing member 4, 4c outer peripheral surface of closing member 4,
5 Metallized layers in through holes of plugging material, 6, 15, 16
Metallized layer, 7 conductive member, 7a end of conductive member, 7b outer surface of conductive member 7, 7c inner surface of conductive member 7, 9 recess of closing member 4, 10, 11, 16
a, 16b Metallized layers having different metal component contents from each other, 19 recesses of ceramic discharge tube

Claims (5)

[Claims] 1. A high-pressure discharge lamp comprising an internal space filled with an ionized luminescent substance and a starting gas, and a high-pressure discharge lamp including an electrode device provided in said internal space. A portion is provided, the opening portion is hermetically sealed using at least a metallized layer, and the metallized layer contains a metal component and a glass component containing at least dysprosium oxide. , High pressure discharge lamp. 2. The high pressure discharge lamp according to claim 1, wherein said metallized layer contains at least dysprosium oxide and molybdenum oxide as said glass component. 3. A high-pressure discharge lamp comprising a ceramic discharge tube in which an internal space is filled with an ionized luminescent substance and a starting gas and an electrode device provided in said internal space, wherein said ceramic discharge tube has an opening. A portion is provided, the opening portion is hermetically sealed by at least a metallized layer, and the metallized layer contains a metal component and a glass component containing at least molybdenum oxide. Discharge lamp. 4. A plugging member which is at least partially fixed to said opening portion of said ceramic discharge tube, wherein said plugging member has a through hole, and a conductive member attached to said plugging member. The high-pressure discharge device according to any one of claims 1 to 3, wherein the closing member and the conductive member are hermetically bonded via the metallized layer. Electric lights. 5. The semiconductor device according to claim 1, further comprising a conductive member, wherein said conductive member is hermetically bonded to said opening portion of said ceramic discharge tube via a metallized layer. The high-pressure discharge lamp according to claim 3.