KR100303570B1 - Structure of light-sealing tube and manufacturing method - Google Patents

Abstract

The sealing part structure of the light-emitting tube for discharge lamps which sealed the opening end part of a bulb by the obturator which has the core part which comprises an electrode, The composition of an electric occlusion body is the coefficient of thermal expansion of a bulb in the bulb side area adjacent to the opening end part of an electric bulb. It is almost the same component as, and in the core part side adjacent to the electric core part, it is almost the same component as the thermal expansion coefficient of this core part, and the component of the intermediate region between the electric bulb side and the core part side is the electric core at the thermal expansion coefficient of the electric bulb side area. The composition ratio is adjusted so as to gradually change with the coefficient of thermal expansion of the negative side, and the bulb side and the electric core side are separated by the intermediate side to form independent bulb side and core side side layers, respectively. At least one or more layers in which the thermal expansion coefficient gradually changes from the electric bulb side to the electric core region It consists of a layer. Preferably, the plural layers of the electric occluder gradually increase in thickness from the electric bulb side layer to the electric core side layer.

Description

[Name of invention]

Light emitting tube encapsulation structure and manufacturing method

[Technical Field]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing structure of a light emitting tube for metal vapor discharge lamps or high brightness discharge lamps such as mercury lamps, metal halide lamps or sodium lamps, and a manufacturing method thereof.

[Background]

Mercury lamp using excitation emission of mercury at the anode pole of hot cathode arc discharge, mercury hot cathode arc light emits metal halides by dissociating them into metals and halogens Metal vapor discharge lamps such as metal halide lamps for emitting light or sodium lamps for emitting yellow light of D line (589.0 nm, 589.9 nm) by hot cathode arcs of sodium vapor have been conventionally used in gymnasiums and factories, It is used as a light source for OHP, color liquid crystal projectors, fog lamps for automobiles and the like.

As a material of a bulb (light emitting tube body) such as a metal steam discharge lamp, quartz glass has been used initially, but since quartz glass is poor in color resistance and has a high heat capacity, the lamp is poorly started, and the dimensions of the bulb are different. Since there exist problems, such as a large deviation, the manufacture of the bulb from light-transmissive ceramics is proposed in recent years.

In general, the light emitting tube for discharge lamps includes a light emitting tube body made of translucent ceramic produced by sintering alumina or the like, and a blocker for encapsulating and fixing the electrode through an electrode support material inside the light emitting tube. do. Thus, in hermetic sealing of the closed body at the open end of the light emitting tube body, the glass solder is filled in the gap between the end face and the inner surface of the open end of the light emitting body main body and the fixing surface of the opposite closed body. The solder is locally heated to melt and then cooled and solidified.

The obturator generally has the same chemical stability as that of the light-emitting tube body or the electrode support material, and the thermal expansion coefficient, the metal vapor, and the halogen vapor.

In addition, when sealing the occluded body by glass solder, a metal component for discharging according to a discharge such as a light emitting plate used in addition to the rare gas for starting, for example, mercury is a high pressure mercury lamp, and a metal halide is a metal halide lamp. It is enclosed in.

When the light tube is turned on, its temperature rises instantaneously at atmospheric pressure and reaches 900 ° C in a stable lit state. For this reason, high thermal stress is generated in the light emitting tube due to such a significant heat change and pressure resistance change.

In general, when thermal stress is applied, thermal stress distortion of the occluded body interposed between the light-emitting tube body and the electrode support material occurs and is destroyed when the thermal expansion coefficient is different. Specifically, uniformity or the like may occur in the glass solder having a higher heat resistance than the light-transmitting ceramic and the blocking body from the blockage itself or its composition, and the discharge metal component in the pipe may leak out of the pipe. As a result, there is a lack of reliability in obtaining stable light emission and the lamp life is limited.

In addition, in a high temperature and high pressure environment in which temperature and internal pressure increase, metal halides (for example, T1I ₃ , NaI, etc.) encapsulated as metal components for discharge are advantageous and become ions, and corrosion by these ions proceeds.

Erosion by free ions also occurs preferentially in glass solders, which are poor in corrosion resistance compared to light-transmitting ceramics and occluders from their composition. Therefore, even if the corrosion resistance with respect to the glass ion, the glass solder easily cracks.

On the other hand, the high-purity translucent alumina used for the bulb is poorly penetrated with the glass solder used for the encapsulation as described above, and has a low adhesive strength at the boundary between the glass and the bulb, so that cracks or encapsulated gas tend to leak out.

In order to solve this drawback, various techniques have been proposed conventionally.

For example, Japanese Patent Application Laid-Open No. 1-143132 proposes a technique for soldering thermal expansion insight material close to alumina to a sealing portion of an alumina outer cycle corresponding to a light emitting body. In addition, Japanese Patent Application Laid-Open No. 63-308861 proposes a technique in which the obturator is composed of a central body and an outer annular body and the solid state joining of the light-emitting tube body and the occluded body (center and annular body). In particular, Japanese Patent Laid-Open No. 63-308861 proposes to specify dimensions and compositions in both the core body and the annular body constituting the obturator. Moreover, specification of the dimension is also proposed by Unexamined-Japanese-Patent No. 62-213061.

By performing such countermeasures, leakage of the discharge metal component in the pipe is suppressed, thereby ensuring the reliability of light emission and prolonging the lamp life.

However, in recent years, it has been pursued to obtain higher luminance of light and increase its added value, and in order to achieve high luminance of light, raising the temperature of the light tube above the conventional temperature (900 ° C) to 1200 ° C has been performed.

At such a high temperature, the cleavage stress is increased, and thus, even in the conventional light emitting tube, it is impossible to sufficiently secure the reliability of light emission and to prolong the lifespan. In addition, it is not preferable to specify the dimensions of the obturator and the like due to restrictions on the shape of the light emitting tube, and furthermore, the shape of the lamp housing the light emitting tube.

The present invention is to provide a light emitting tube with high reliability and long life, which has been made to solve the above problems, and particularly, to provide a novel encapsulation structure thereof and a simple manufacturing method thereof.

[Initiation of invention]

Means and procedures employed by the present invention in order to achieve this object are as follows. In the sealing part structure of the light emitting tube which sealed the opening end part of a bulb by the obstruction body which has an electrode which comprises an electrode, the composition component of the said obstruction body is a bulb side region adjacent to the opening edge part of the said bulb. Iv) is almost the same component as the thermal expansion coefficient of this bulb, and in the core part side adjacent to the core part, the component is almost the same as the coefficient of thermal expansion of the core part, and in the middle region between the bulb side and the core part side. A component ratio is comprised so that a component may change gradually from the thermal expansion coefficient of the said bulb side area | region to the thermal expansion coefficient of the said core part side area | region. Further, the bulb side station and the core side station are separated by an intermediate station therebetween to form independent bulb side station layers and a core side station layer, and the intermediate station has the coefficient of thermal expansion from the bulb side station to the core side station. It consists of at least 1 or more layers which are gradually changing.

More preferably, the plurality of layers of the obturator are configured to gradually increase in thickness from the bulb side layer to the core side layer.

The bulb as the light emitting tube is preferably made of a transparent ceramic, in particular of high purity alumina, and the core portion thereof is preferably made of tungsten.

In addition, the obturator may be made of an inclined functional material.

As described above, the method for manufacturing the encapsulation portion structure of the light emitting tube is as follows.

In the method of manufacturing a light emitting tube in which an opening end of a light-transmissive bulb is encapsulated by a blocking member having a core part constituting an electrode, (a) the core as a composition ratio based on the fine powder of a light-transmissive bulb component and the core part component. A bulb component suspension having a larger permeable bulb component than a subcomponent, a core component suspension having a larger permeable bulb component and a core component, and at least one intermediate portion between the suspensions with respect to the composition ratio of the translucent bulb component and the core component. A suspension preparation step of preparing a suspension, and (b) a microbulb-bulb-measuring layer adjoining the translucent bulb using the bulb component suspension, and adjacent to the core portion having the electrode using the core component suspension. A core portion side layer is formed, and the at least one kind is formed between the bulb side layer and the core portion side layer. On the step of using the suspension medium forming the unsintered layered product to form a fine resolution intermediate yeokcheung at least one or more and, (c) and in its base comprises the step of sintering the unsintered layered product.

In particular, the step (b) comprises (d) a plurality of mold members made of a porous body joined together, and using the mold to form a cavity therein, the bulb component suspension is injected into the cavity of the mold. Penetrating the solvent of the suspension into the mold, and then discharging excess suspension to form the bulb side layer on the inner circumferential surface of the cavity; and (e) the at least one intermediate suspension and the core component thereafter. A step of forming the molded laminate by repeating the injection, infiltration of the solvent, and the treatment of the solvent on the inner circumferential surface of the bulb side layer in the same manner as in the case of the bulb component suspension; Each of the mold members constituting the molding is separated to form the green laminated body including the step of releasing the molded laminate.

Or as said process (b), each green sheet is produced using a core part component suspension, the said at least 1 sort (s) or more intermediate suspension liquid, and the said bulb component suspension, and this green sheet is wound one by one with respect to the outer peripheral surface of the said core part. You may also include a process.

In the encapsulation portion structure of the light emitting tube described above, in particular, a light emitting tube made of a light-transmissive ceramic, the core is made of a conductive core made of tungsten or the like, and a closed body that is solid-phase bonded to the opening of the light emitting body or bulb has its conductivity. The sintered compact was laminated by sintering a core-side region layer, at least one or more intermediate region layers, and a bulb-side region layer from the core to the bulb. Further, the composition of each layer is that the core portion side layer comprises at least 50% by volume of the conductive core portion component, for example, the bulb side layer has at least 80% or more by volume ratio of the transparent ceramic component, and between the core portion side layer and the bulb side layer The closer the volume of each intermediate region to the bulb side, the closer the volume ratio of the translucent ceramic component to the volume ratio in this bulb side layer, and the closer the core portion side to the volume ratio of the conductive core component, It was close.

In each of the layers in the occluded body, crystals are formed in a mesh structure by sintering between common components to integrate.

Bonding of the core part and the opening of the light-emitting tube body is applied with a sintering process as the surface energy decreases. In the meaning of this composition, a small amount of impurities such as glass components are often added.

As a result, each layer surrounds the powder of the conductive core portion component, and the light-transmissive ceramic component is dissolved and crystallized, and adjacent layers are solidified by solid-phase joining together by crystallization of the light-transmissive ceramic component in each layer at the bonding surface of each layer. In addition, the conductive core portion and the core portion side-side layer are crystallized in a state in which the translucent ceramic component in the core portion side-side layer is in contact with the core portion, and is buried in the glassy substance produced by the grain boundary and the conductive core portion component By being included in this core part and a core part side layer in common, it is also integrated by solid-phase bonding. In addition, the bulb side layer and the light emitting tube body (bulb) crystallize in a state where the light transmissive ceramic component in the bulb side layer is in contact with the light tube body, and the grain boundary is buried on the glass, and at the same time, the light transmissive ceramic component is bulbous. It is also included in the stationary layer and the orphan tube main body, so that the solid phase is also integrated.

For this reason, the sintered block after sintering firmly bonds with the conductive core to enable sealing of the main electrode. In addition, the blockage after sintering allows airtightness of the opening of the light emitting tube body through glass at the grain boundary of the light transmissive ceramic component in the bulb side layer and the light emitting tube body.

Moreover, the distribution of thermal expansion rate from the conductive core portion to the light emitting tube body through the core portion side intermediate layer, the intermediate reverse layer and the bulb side reverse layer is inclined from the thermal expansion rate of the conductive core portion until the thermal expansion rate of the light emitting tube body is reached. One distribution.

In addition, the manufacturing method of the structure of the encapsulation portion of the light emitting tube is formed by sintering a closed body hermetically solid-bonded to the opening of the light emitting tube body formed of the light-transmissive ceramic. The reverse layer, the microcrystalline center, and the green bulb side-reverse layer are sequentially laminated to form a microcrystalline laminate.

Each layer of the green core core layer, the green mid layer and the green bulb side layer, which is thus laminated, preferably contains a conductive member component or a powder of the core component and a conductive member component containing a powder of a transparent ceramic component or a bulb component. A translucent ceramic component containing a core component suspension adjusted to at least 50% or more by volume ratio and a powder of the cationic component, and a translucent ceramic component containing a bulb component suspension adjusted to at least 80% or more by a volume ratio and a powder of the cationic component It is formed by using a plurality of intermediate suspensions adjusted by increasing the volume ratio of the translucent ceramic component until the value becomes approximate 100% in volume ratio and decreasing and inclining the conductive member component at 100% in volume ratio.

And when laminating | stacking each layer of a green core part side layer, a green half intermediate layer, and a green bulb side layer to the outer periphery of a core part sequentially, it laminates in order of high volume ratio of a conductive member component, Thereafter, the green laminate is placed and sintered in the opening portion of the light emitting tube body in which the main electrode connected to the core portion is located in the light emitting tube body.

Therefore, after sintering, each layer takes powder of the core component and the light-transmissive ceramic component solidifies and crystallizes, so that the obstructed body after sintering is integrated through the solid solution and crystallization of the light-transmissive ceramic components in adjacent layers. The sintered block after sintering is firmly bonded to the core part through the formation of a glass phase at the grain boundary in the state in contact with the core part of the translucent ceramic component in the core part side layer and the coexistence of the conductive core component to seal the main electrode. Makes it possible. In addition, the blockage body after sintering enables the airtightness of the opening part of the light emitting tube main body to be formed by forming a glass phase at the grain boundary of the light transmissive ceramic component in the bulb side layer and the light emitting tube body.

In addition, the distribution of the coefficient of thermal expansion from the core portion through the core portion side intermediate layer, the intermediate portion layer and the bulb reverse layer to the light emitting tube body is inclined from the core portion's thermal expansion rate to the thermal expansion rate of the light emitting tube body (bulb). It is a distribution.

[Brief Description of Drawings]

1 is a cross-sectional view of a light emitting tube according to Embodiment 1 of the present invention.

2 is a graph showing the particle size distribution of the light-transmissive alumina used for the production of the main body or bulb of the light emitting tube and the obturator,

3 is a process chart for explaining a manufacturing process of the occluded body of the light emitting tube,

4 is a perspective view of the obturator;

5 (a) to (c) is a cross-sectional view showing the structure and distribution of the composition and the composition distribution diagram,

6 is a process chart for explaining a manufacturing process of the occluder of the light emitting tube according to Example 2 of the present invention.

7 is a perspective view of a molded body in which the occluded body is in a microcrystalline state,

8 (a)-(b) are perspective views of the coupling type used for producing the above-described obturator,

9 is a perspective view when the auxiliary member is attached to the coupling type,

(A)-(b) is explanatory drawing for demonstrating the manufacturing process of the said obturator,

11 is a cross-sectional view of the obturator formed in the coupling mold,

12 is a distribution chart of each composition component of the obturator;

13 is a cross-sectional view when an electrode is attached to the obturator in the above microcrystalline state,

14 is a cross-sectional view when the obturator is assembled to the light emitting body (bulb).

15 is a cross-sectional view of the light emitting tube when a part of the above embodiment is changed;

16 is a sectional view of a light emitting tube according to a third embodiment of the present invention;

FIG. 17 is an explanatory diagram showing a step of adjusting slip for the occlusion body used in the light emitting tube; FIG.

18 (a) to (e) are explanatory diagrams showing a slip casting process,

19 is a sectional view of the light emitting tube when a part of the third embodiment is changed;

20 is a sectional view of a light emitting tube according to Embodiment 4 of the present invention.

21 is an explanatory diagram of raw materials used to manufacture the light emitting tube.

22 is an explanatory diagram of each slip used in the manufacture of the light emitting tube,

23 (a)-(f) are process charts showing the manufacturing process of the said light emitting tube,

24 is a sectional view of a light emitting tube according to a fifth embodiment of the present invention;

25 is an explanatory diagram of each slip used in the manufacture of the light emitting tube,

FIG. 26 is a perspective view of a cylindrical pipe used for manufacturing the light emitting tube,

(A)-(b) is a process chart which shows the manufacturing process of the said light tube,

28 is a cross sectional view of a light emitting tube according to a sixth embodiment of the present invention;

29 (a) to (e) are explanatory diagrams showing each slip and a manufacturing process used for producing the occluded body of the light emitting tube,

30 (a) to (d) are explanatory diagrams in the case of partially modifying the method for manufacturing the occluded body of the light emitting tube.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, the Example which the light emitting tube which concerns on this invention is preferable is demonstrated by drawing.

As shown in FIG. 1, the light emitting tube of Example 1 has a small diameter and a blockage body 2 fixed to a cylindrical light emitting tube body (or bulb) 1F and an electrode holding hole 1a which is an opening end of a large diameter. The block 2A fixed to the electrode holding hole 1b, which is an open end of the pair, and a pair of main electrodes 3 arranged in the light emitting tube body 1F are provided. The pair of main electrodes 3 are made of tungsten coils, and are supported via tungsten support shafts 4 passing through the obturators 2 and 2A.

The obstructions 2 and the obstructions 2A are only different in diameter, and are respectively produced through a manufacturing process described later.

In addition, an inlet capillary 1c for injecting a rare gas for starting metal or amalgam of various discharge materials is provided at the end face of the light emitting tube main body on the electrode holding hole 1b side. It is sealed by metal sealing agent 1d, such as cermet) and nickel.

In addition, the manufacturing process of the light emitting tube 1 which starts the manufacturing process of the light emitting tube main body 1F and the obturator 2, the support of the main electrode 3 via the support shaft 4, etc. are demonstrated one by one.

First, the synthesis of fine alumina powder, which is a raw material of the light-emitting tube body and the occluder, will be described.

In order to synthesize this fine alumina powder, when pyrolyzed, an aluminum salt of alumina having a purity of 99.98 mol% or more is prepared as its starting material.

Examples of such a high purity aluminum salt for alumina synthesis include ammonium alum, aluminum ammonium, carbonite, hydrooxycite (NH ₄ AlCO ₃ (OH) ₂ ), and the like.

The aluminum thus prepared is weighed, and once made into a suspension solution using distilled water and a dispersant, it is dried by a spray drying method. Thereafter, pyrolysis is carried out to obtain fine powder of alumina alone. Here, in performing pyrolysis, it is processed for 2 hours at 900-1200 degreeC, for example, 1050 degreeC in air | atmosphere. As a result, through this spray drying and pyrolysis, an alumina fine powder having an average particle diameter of 0.2 to 0.3 µm and a purity of 99.99 mol% or more is synthesized, and preparation of the fine alumina powder is completed. Further, the synthesized fine alumina powder is agglomerated to obtain a fine agglomerate having a larger particle size than the fine alumina powder.

On the other hand, as a raw material for the occluders other than alumina, a fine tungsten powder having a purity of 99 mol% or more and an average particle diameter of about 0.5 mu m is prepared.

The light-emitting tube body 1F and the obturator 2 are produced from these raw materials, respectively.

The light tube main body 1F is manufactured as follows.

First, an organic binder mainly composed of an acrylic thermoplastic resin is blended into the fine alumina powder (secondary aggregate) synthesized as described above, and wetted for about 24 hours using a plastic (nylon) ball mill using an organic solvent (alcohol, benzene, etc.). Mix and wet the organic binder and aluminum powder sufficiently. Again, distilling to remove the solvent to kneading the compound of the desired viscosity (50,000 ~ 150,000cps).

The organic binder is a mixture of an acrylic thermoplastic resin, a paraffin wax and an atactic polypropylene. Therefore, the compounding quantity of these organic binders with respect to 100 g of fine alumina powders is 25 g in total amount.

Each component of the said organic binder is mix | blended as follows, and the sum total of each component turns into the total amount (25g) of the said organic binder.

20-23 g of acrylic thermoplastic resin (preferably 21.5 g)

Paraffin wax less than 3g (preferably 2.0g)

Less than 2g of atactic polypropylene (preferably 1.5g)

Moreover, in distillation drying at the time of compound preparation, it distills and dryes at 130 degreeC for 24 hours, and heat-kneaks (130 degreeC) using the alumina roll mill after that, a compound of a desired viscosity is obtained.

Then, a molded article having the shape shown in FIG. 1 is formed by injection molding using a mold apparatus (not shown). The molded article thus formed is heated to a temperature at which an organic binder such as an acrylic plastic resin is pyrolyzed and completely carbonized in a nitrogen atmosphere to degrease the molded article. The specific heating upper limit temperature of the initial heat treatment may be determined depending on the capacity of the heat treatment furnace to be used or the thermal decomposition temperature of the organic binder. In this embodiment, the temperature was raised from room temperature (20 ° C.) to 450 ° C. for 72 hours. Other treatment conditions are as follows. In addition, the constant pressure was maintained during the temperature increase to 450 degreeC.

Treatment Pressure 1 ~ 8㎏ / ㎠ (Optimal Pressure 8㎏ / ㎠)

72 hours or less when the temperature is raised from 20 ° C to 450 ° C

That is, by performing initial heat treatment, organic binders such as acrylic thermoplastic resin, paraffin wax, and atactic polypropylene blended at the time of compound preparation are thermally decomposed and carbonized to degrease the molded body.

Subsequently, a post-insulation process according to the following conditions is carried out in air, and the molded body (degreasing body) is sintered to obtain a sintered body. At this time, it heated up at 100 degreeC / hour.

Treatment temperature 1200 ~ 1300 ℃ (optimum temperature 1235 ℃)

Holding time 0 to 4 hours (optimum 2 hours) at the processing temperature

Performing sintering in the post-insulation process at a temperature range of 1200 to 1300 ° C causes the density after sintering to be 95% or more relative to the theoretical density and to apply hot isotatic pressing in the post-process, and to coarse the sintered body. ) To avoid the formation of crystals. In other words, when the sintering is performed at 1200 ° C. or lower, the density after sintering is less than 95% of the theoretical density, so that the hot hydrostatic press is not applied, and at 1300 ° C. or more, the frequency of formation of coarse crystals of the sintered body increases, which is disadvantageous in strength. .

By sintering after degreasing by performing the initial heat treatment and post-stage heat treatment, the volume shrinkage is 82.5% of the molded body before sintering, and the filling rate after sintering is almost 100% (volume density 3.976). In addition, the carbide modified during the initial heat treatment until the completion of the post heat treatment is completely burned off from the sintered body.

Thereafter, the sintered compact is subjected to a hot hydrostatic press under an argon atmosphere or an argon atmosphere containing 20 vol% or less of oxygen under the following conditions. At this time, it heated up at 200 degreeC / hour. In this way, light transmittance is expressed in a sintered compact.

Treatment temperature 1200 ~ 1250 ℃ (optimum temperature 1230 ℃)

Processing Pressure 1000 ~ 2000atm (Optimal Pressure 1000atm)

Processing time 1 ~ 4 hours (optimal processing 2 hours)

Here, the hot hydrostatic press and the temperature range and the pressure range are performed in order to obtain the desired high light transmittance, to improve the mechanical strength, and to avoid the damage in the middle of the hot hydrostatic press. That is, if the hot hydrostatic press is performed at less than 1200 ° C. or less than 1000 atm, only low light transmittance is obtained, or conversely, if it exceeds 1250 ° C., abnormal particle growth is promoted to result in a decrease in mechanical strength or light transmittance. If it exceeds 2000atm, it is because crack concentration occurs due to stress concentration where the grooves and the like exist even if the bores or grooves, etc. existing in the sintered body are extremely fine.

Subsequently, a diamond grinding stone, not shown, is ground and polished to the end face of the sintered compact to remove edges, thereby completing the light emitting tube body 1F made of alumina. That is, as shown in FIG. 1, the light emitting tube main body 1F is produced with retaining holes 1a and 1b at both ends.

The inner and outer surfaces of the light-emitting tube body 1F thus obtained are ground and polished to a thickness of 0.2 mm or less with a brush attached to diamond grindstone particles having a particle size of 0.5 mu m. This surface polishing removes irregularities and the like on the surface of the light emitting tube to prevent scattering of light on the surface, thereby improving direct transmittance.

The light emitting tube main body 1F has an inner diameter d of the light emitting area of about 4.0 mm, a thickness of about 0.3 mm, and a total length of about 40 mm, and has the following physical properties. In addition, as a result of histological observation by a transmission electron microscope (TEM), the presence of grain boundary phases, light scattering sources, and voids and lattice defects inside crystal grains, did not occur. Moreover, the diameter of the small diameter electrode holding hole 1b is about 1 mm or less.

Linear transmittance for visible light (wavelength 380 ~ 760㎜): 70% or more

Linear transmittance for 500mm wavelength: 82% (thickness: 0.5mm)

Average particle size of crystal grains: about 0.7㎛ (maximum particle size about 1.4㎛)

Mechanical strength (JIS R1601)

Flexural Strength St

(Room temperature) = 98 kg / cm 2

Weibull coefficient

(Room temperature) = 9.3

(900 ° C.) = 8.1

For the measurement of the particle diameter and the strength, a sample produced separately (as for shape, sample, etc., according to JIS R1601) was used as a substitute for the light-emitting tube body 1F of the present embodiment. In addition, the preparation of the sample followed the conditions of the above process.

Calculation of the particle size is performed by using diamond grindstone particles on the surface of the sample prepared separately so that development, thickness, etc. conform to JIS R1601, and etching the grain boundary with molten potassium hydroxide, and then observing the sample surface with a scanning electron microscope. And image analysis of the outlines of the crystal grains. In image analysis, the crystal grains were assumed to be spherical bodies or polygonal bodies, and the maximum values of their diameters and distances between vertices were used for the particle size calculation. FIG. 2 shows a distribution diagram of particle diameters assuming crystal grains as spherical bodies.

About the measurement of the linear transmittance, the said separately prepared sample was made into 0.5 mm thickness, and both surfaces were rough-finished and it calculated | required with the double beam spectrophotometer.

The reason why the light tube body 1F made of the light-transmissive alumina thus obtained has light transmittance while having a microcrystalline particle diameter different from that of the generally light-transmissive ceramic is considered as follows.

First, since the oxides such as MgO mixed with the first degree impurity contain only a very small amount (up to 0.01 mol% or less in total) in the alumina powder, the impurities are dissolved in all of the alumina and hardly form grain boundaries. For this reason, in general transmissive alumina, it is thought that the influence by the grain boundary image which acts as a scattering factor of light is excluded, and the linear transmittance with respect to visible light is improved.

It is also inferred as follows.

Assuming that both the crystal grains and the cross sections of the crystal grains are circular, when n crystallites of diameter d gather to form crystal grains of diameter D, the following relational expression 1 holds.

① n = (D / d) ²

The value of n calculated from this relational expression can be converted into the crystalline interface contained in the cross section of one crystal grain.

The lattice constants of various light-transmissive aluminas (average particle diameter; 0.72, 0.85, 0.99, 1.16, 1.35, 1.52 µm) obtained from high purity alumina were obtained by using an X-ray diffraction apparatus, and the relation between the diameter d of the crystallites and the width of the diffraction lines From the diffraction peak of (012) according to Scherrer's equation, the diameter d of the crystallites of the translucent alumina of the average particle diameter was calculated, and the diameter d of the crystallites was constant regardless of the size of the crystal grains. Scherrer's expression is "P. Gallezot, ″ Catalysis, Science and Technology, Vol. 5, p221, Springer-Verlag (1984) or P. Scherrer, ″ Gottinger Nachrichen, 2, 98 (1918).

Therefore, it is said that the smaller the diameter D (average particle diameter) of the crystal grains is, the smaller the crystalline interface in one crystal grain is.

In general, when light is incident on a polycrystalline body such as a ceramic, the scattering thereof is considered to occur on the surface where the refractive index is discontinuous, that is, the portion where the atomic arrangement is discontinuous. The crystallite interface in the crystal grains causes light scattering because only this portion of the crystal array is discontinuous. Therefore, the smaller the crystalline interface in the crystal grains, that is, the smaller the diameter D of the crystal grains, the smaller the influence of the crystalline interface, which is the scattering particles of light, is believed to result in an improvement in the linear transmittance to visible light.

Next, the occluders 2 and 2A are produced as follows. The manufacturing process of this obturator is demonstrated using the process diagram of FIG.

First, a vehicle for use in suspending the alumina fine powder (secondary aggregate) and tungsten fine powder synthesized as described above is prepared from various organic substances shown in Table 1 (Step 1). In the preparation of the vehicle, various organic substances are weighed and mixed uniformly with a mixer.

TABLE 1

Then, the fine alumina powder, the preparation vehicle, the organic solvent (butyl diphthalate) and the dispersant (ammonium carbonate) are combined in the volume ratios shown in Table 2, and the mixture is kneaded with three rolls to prepare an alumina slurry (step 2).

TABLE 2

Further, the fine tungsten powder, the prepared vehicle, the organic solvent (butyl diphthalate) and the dispersant (ammonium carbonate) are combined in the volume ratios shown in Table 3, and kneaded with these three rolls to prepare a tungsten slurry (step 2). .

TABLE 3

Next, the volume ratio (tungsten / alumina) of tungsten and alumina was calculated using the alumina slurry combined and prepared at the volume ratio shown in Table 2 and the tungsten slurry combined and prepared at the volume ratio shown in Table 3. Eight kinds of tungsten-alumina mixed slurries are prepared (step 3).

TABLE 4

Each mixed slurry thus prepared is sufficiently mixed so that alumina and tungsten are uniformly dispersed, and then bubbles are removed from each mixed slurry (step 4). Specifically, each mixed slurry is placed in a resin container in a vacuum desiccator, and the slurry in the resin container is stirred with a magnetic stirrer or the like, and the air in the desiccator is mixed with a vacuum pump for several ten minutes (for example, about 20 minutes). Aspirate. When this vacuum degassing | defoaming, some organic solvents were volatilized and the slurry viscosity was 30,000 cP.

Next, each mixed slurry shown in Table 4 was placed on the outer circumference of the tungsten support shaft 4 supporting the electrode portion 3 as the core portion of the obturator, that is, the first layer slurry. From the first layer slurry to the outer periphery of the support shaft 4 as shown in FIG. The grounding and stacking up to the eight-layer slurry is performed sequentially from the first-layer slurry by applying and drying the slurry of each layer.

In this way, the innermost peripheral layer made of the first layer slurry is formed in the core part side liquid adjacent to the core part of the occluded body, and the plurality of layers of the second layer slurry to the seventh layer slurry is formed in the intermediate region of the occluded body. The outermost layer of the eighth-layer slurry is formed in the bulb side station adjacent to the intermediate layer and the bulb opening end of the obturator.

The composition distribution of this laminating agent 20 is obtained from the support shaft 4 as evident from Figs. 5 (a), (b) and (c) showing the relationship between the cross sectional view and the tungsten and alumina volume ratio of each slurry. Towards the outside, the volume ratio of alumina as shown in FIG. 5 (c) increases and inclines until it is close to 100%, and the volume ratio of tungsten as shown in FIG. 5 (b) decreases and inclines to 80%.

Next, the lamination agent 20 is heat-treated at 600 ° C for 10 hours in a hydrogen-containing hydrogen reducing atmosphere to degrease the lamination agent 20 (step 6). That is, the heat treatment decomposes and forms the organic substance and the organic solvent of the vehicle component which were mix | blended at the time of slurry preparation by carbonization.

Subsequently, the laminated agent 20 (degreasing body) after degreasing is sintered (step 7), and the obstructions 2 and 2A which are this sintered body are obtained. Further, carbides denatured during the initial heat treatment until the completion of the post heat treatment are completely burned off from the sintered body.

In each of the layers of the occluders (2) and (2A), network structural crystals are formed and integrated by sintering between common components. The joining of the electrode holding holes 1a, 1b of the support shaft 4 or the light emitting body main body 1F is subjected to a sintering process in accordance with the decrease in surface energy. It is common to add a trace amount of impurities, such as a glass component, in the meaning of composition.

That is, in this sintering process, each layer of the laminate 20 is surrounded by tungsten powder and alumina is dissolved and crystallized, and adjacent layers are solidified by solid phase bonding by alumina of each layer being crystallized by mutual solid solution at the bonding surface of each layer. do. In addition, the innermost circumferential layer of the support shaft 4 and the first layer slurry is crystallized in the state in which the alumina of the innermost circumferential layer is in contact with the support shaft 4, forms a glassy material at its grain boundary, and at the same time tungsten This support shaft 4 and the innermost circumferential layer are contained in common so that they are integrated by solid phase bonding. As a result, the obstructions 2 and 2A obtained after sintering are firmly combined with the support shaft 4 supporting the main electrode 3, so that the support shaft 4, i.e., the main electrode 3 is light-emitting tube. The main body 1F is hermetically sealed and fixed.

In addition, the distribution of the thermal expansion rate from the support shaft 4 to the outermost circumferential layer through the innermost circumferential layer and the multilayer intermediate layer is determined by the composition distribution of the thermal expansion rate of the support shaft 4 (thermal expansion rate of tungsten). ) Is inclined distribution until the thermal expansion rate (alumina thermal expansion rate) of the light-emitting tube body (bulb) 1F and an approximate thermal expansion rate are reached.

After sealing and fixing the support shaft 4 in this way, as shown in FIG. 1, the occluders 2 and 2A are fitted to the electrode holding holes 1a and 1b of the light emitting main body 1F. By cutting or grinding the outer periphery of the outermost layer of (step 8), the occluded body is completed, and all of its manufacturing processes are completed.

Next, the coupling with the light-emitting tube body 1F of the completed occluders 2 and 2A and the fabrication of the light-emitting tube 1 will be described.

First, as shown in FIG. 1, the blocking member 2A (same as those in FIG. 4 and FIG. 5) subjected to sintering and circumferential processing is fitted into the electrode holding hole 1b of the light emitting tube main body 1F, and the light is emitted. The inner circumferential surface of the electrode holding hole 1b of the tube body 1F and the outer circumferential surface of the obturator 2A are brought into contact with each other. The infrared or high power laser is then irradiated locally over this contact range and concentrated to heat.

By this localized heating, alumina in the outermost layer of the eighth-layer slurry of the obturator 2A and alumina in the light-emitting tube body 1F are sintered and crystallized, and grain boundaries are spun at their joint surfaces. The buried body 2A and the light-emitting tube body 1F are solid-bonded because they are buried by a glass image mainly composed of structures such as garnets. As a result, the occluded body 2A and the light emitting tube body 1F are hermetically fixed by the outermost layer and the light emitting tube main body 1F by forming a glass phase at the alumina grain boundary.

Similarly, the sintered and circumferentially processed obturator 2 (see Figs. 4 and 5) is fitted into the electrode holding hole 1a of the light emitting tube body 1F, and the contact range thereof is irradiated with an infrared or high power laser. By heating locally. Thus, the obturator 2 and the light-emitting tube main body 1F are solid-fit and tightly fixed to each other so that the starting gas gas and the discharge material are sealed.

Subsequently, a start-up ash metal and a discharge material that emits light in a desired color (Sn-based, Na-Tl-In-based, Se-Na-based, and Dy-Tl-based alloy) in the light-emitting tube body 1F sealed at both ends. Alternatively, amalgam of each metal halide) is sealed through the inlet tubule 1c and sealed with the sealing agent 1d.

Since the occluders 2 and 2A and the light tube main body 1F are solid-state junctions which do not use solder glass or the like as in the related art, leakage of the encapsulation component is surely avoided.

In this way, the light-emitting tube body 1F having the main electrode attached thereto is generally used after being incorporated into the exterior of a high-pressure discharge lamp such as a metal halide.

Next, a light emitting tube (invention product) having the tungsten volume ratio of the innermost layer of the occluded body 2 of Example 1 or the alumina volume ratio of the outermost layer as various values within the scope of the present invention, and these volume ratios are outside the scope of the present invention. The light emitting tube (comparative product) and the alumina occluder were compared with the light emitting tube (traditional product) in which the alumina-based cermet was fixed to the light emitting tube body. The comparison results are shown in Tables 5 and 6. The light emitting tube main body 1F is the same as that of the light emitting tube of this embodiment. The innermost layer, the outermost layer, and the number of layers in which each of the intermediate layers are combined are set to various values as shown in the table, and the alumina and the tongue from the innermost layer through each intermediate layer to the outermost layer are reached. The volume ratios of the stainless steels were made to increase and decrease inclination, respectively.

As an evaluation item of durability of these light tubes, a cumulative lighting period (lighting life) was employed in the case where the thermal stress was repeatedly applied for 5 hours of lighting period and 0.5 hours of extinction. In this case, Hg-TII ₃ (0.11 g) was sealed as a material for discharge, and a voltage of 100 V (100 W) was applied to the pair of main electrodes 3 and turned on. In addition, when the encapsulating material leaks, the stable lighting state becomes remarkably unstable, and thus the accumulation of the lighting period is stopped at the time when such an unstable lighting state is achieved.

TABLE 5

* 1: Measurement is impossible due to poor conduction

About the same as discharge materials in the case of sealing a _{Hg-TII-NaI-InI 3} (0.13g) was carried out for the comparative test. The results are shown in Table 6.

TABLE 6

* 2: Measurement is impossible due to poor conduction

From the above experimental results, even if the light emitting tube of the embodiment of the present invention is turned on and off, extremely high durability can be obtained. That is, according to the light emitting tube of this embodiment, its thermal expansion coefficient approaches the support shaft 4 and the light emitting tube main body 1F, and the support shaft 4 or the light emitting tube main body 1F having the main electrode 3 at its tip. Since the obstructions 2 and 2A inclined to the thermal expansion coefficient are solid-bonded, thermal stress resistance can be improved. As a result, because of excellent thermal stress resistance, light emission reliability can be improved and a long lifetime can be achieved. In addition, such a light emitting tube can be easily provided.

In addition, the luminance of the light emitting tube of the invention when Hg-TII ₃ (0.11 g) was sealed as a material for discharge was 183,000 nt. In addition, when Hg-TII-NaI-InI ₃ (0.13 g) was encapsulated, the luminance was 240,000 nt.

In addition, the light emitting tube body 1F of the present embodiment is a light-transmissive alumina made of fine crystal grains having an average particle diameter of about 0.7 μm and a maximum particle size of about 1.4 μm, and does not form a grain boundary phase. The mechanical strength (bending strength, waffle coefficient) is improved over the light emitting tube of a general translucent ceramic in which sintering together with a sintering aid such as MgO to coarse crystal grains. As a result, according to the light emitting tube using the light emitting tube main body 1F of the present embodiment, the above-mentioned long life can be reduced. When the thickness is reduced, the heat capacity of the light emitting tube itself decreases, so that the light emitting tube rapidly warms up to a predetermined temperature. Thus, it is possible to shorten the startup time until the metal component for discharge evaporates and becomes saturated steam pressure and the lighting is stable.

In addition, due to the fact that the grain boundary phase inside the crystal grain, which is the light scattering factor, is reduced by the small particle diameter, light scattering between the light passing through the wall surface of the main body of the light emitting tube 1F is suppressed. It has a high linear transmittance of 70% or more for light (visible light) having a wavelength of ˜760 nm (linear transmittance: 82%, thickness: 0.5 nm) for light having a wavelength of 500 nm. For this reason, the brightness | luminance in the high-pressure discharge lamp of the light emitting tube 1 using this light tube main body 1F is improved.

In addition, since the grain boundary phase does not exist as in the prior art, erosion at the grain boundary due to the metal vapor component (ion) for discharge is suppressed, and even if the leakage of the metal vapor component for discharge out of the light emitting tube is thinned. That is, even if it is thin, since the leakage of the metal vapor component for discharge from the light emitting tube wall surface is prevented, the lifetime of a high brightness discharge etc. can be extended. In addition, the light emitting tube 1 of the present embodiment uses the electrode holding hole 1b with a small diameter to reduce the amount of encapsulant, thereby suppressing the erosion of the encapsulation by the metal vapor component (ion) for discharging. Leakage of the vapor component can be more reliably avoided.

Next, Example 2 of the present invention will be described. In Example 2, the manufacturing process and the structure of the occluder of the light emitting tube of Example 1 are different. Therefore, this is explained in full detail. In addition, in this description, the superscript code a is attached to the code | symbol of the member of the said Example 1, and it demonstrates.

The manufacturing process of the obturator 2a of Example 2 is demonstrated using the process diagram of FIG.

As shown in FIG. 6, 11 types of slurry whose volume ratio (tungsten / alumina) of tungsten and alumina are prepared from the alumina powder and fine tungsten powder are prepared (step 1).

First slurry: tungsten / alumina = 100/0

Second slurry: tungsten / alumina = 90/10

Third Slurry: Tungsten / Alumina = 80/20

4th slurry: tungsten / alumina = 70/30

Fifth Slurry: Tungsten / Alumina = 60/40

Slurry 6: Tungsten / Alumina = 50/50

7th slurry: tungsten / alumina = 40/60

Eighth slurry: tungsten / alumina = 30/70

9th slurry: tungsten / alumina = 20/80

Slurry No. 10: Tungsten / Alumina = 10/90

11th slurry: tungsten / alumina = 0/100

Preparation of each said slurry is performed as follows. First, the fine alumina powder and the fine tungsten powder are weighed so that their volume ratio is the respective numerical values, and an ammonium carbonate dispersant is blended with distilled water in each of the weighed powders. Then, this was wet mixed with a ceramic (alumina) ball mill for about 24 hours to loosen excess agglomerates while fine powders of alumina and tungsten were uniformly present in the solution.

The blending ratio (volume ratio) of the ammonium carbonate dispersant to the fine powder in each slurry is 2 g relative to 100 g of the total amount of fine powder in each slurry.

Next, bubbles are removed from each prepared slurry (step 2). Specifically, the slurry taken out of the ball mill is placed in a resin container in a vacuum desiccator, and the air in the desiccator is mixed with a vacuum pump for several ten minutes (for example, 20 minutes) while stirring the slurry in the resin container using a magnetic stirrer or the like. Aspirate.

Then, the desired molded body 20a shown in FIG. 7 is molded using the coupling die 10 shown in FIG. 8 (a) through the following steps. Moreover, in the molded object 2a and the obturator 2a of FIG. 7 and FIG. 10 mentioned later, the aspect ratio of the figure is not 1: 1.

The combined mold 10 is a mold 11a, 11b of left and right objects formed of a porous inorganic material such as gypsum or a porous resin having a fine hole having a function equivalent to that of gypsum. It is comprised by joining as shown, and the slurry injection space 13 is formed in the joining surface of the mold 11a, 11b.

As shown in Fig. 8 (a), each of the molds 11a and 11b has curved grooves (cavities) 13a and 13b at its lower end on the joining surfaces 15a and 15b. Have The grooves 13a and 13b are cut into the joining surfaces 15a and 15b by an end mill having cutting teeth of the configuration at the tip. Moreover, (13a) and (13b) can be shape | molded from the beginning to joining surface 15a and 15b.

Next, the slurry after the bubble removal is injected into the slurry injection space 13 of the bonded die 10 and the molding is sequentially performed from the one with the highest alumina content, that is, from the eleventh slurry to the first slurry (step 3). It demonstrates concretely below.

First, as shown in FIG. 9, the cylindrical body 17 is provided in the upper surface of the coupling die 10, and 11th slurry is inject | poured into this cylindrical body 17. As shown in FIG. In addition, a slurry having a volume of the slurry injection space 13 is injected into the cylindrical body 17. The lower surface of the cylindrical body 17 and the upper surface of the coupling die 10 are sealed by arranging the clay 19 in the tubular shape at the lower end of the cylindrical body 17. Rubber may be used instead of clay.

Thus, the mixture is allowed to stand for a predetermined time while the eleventh slurry is injected into the slurry injection space 13, and the solvent component (here, distilled water) of the eleventh slurry is capillaryly formed in the pores of the porous squares 11a and 11b. Is sucked into the mold. For this reason, the powder (alumina powder in the 11th slurry) bonded to the wall surface of the slurry injection space 13 by the ammonium carbonate dispersant as shown in FIG. 10 (a) and 10 (b) is the surface of the wall surface. It is uniformly ground according to the thickness, and the thickness of the thin layer 11S is determined. The leaving time is previously determined by experiment so that the thickness of the thin layer 11S formed for this purpose becomes a predetermined value. In addition, in this setting time and setting of the slurry injection space 13, volume shrinkage at the time of sintering, etc. are also estimated and determined. The leaving time of this Example was adjusted suitably so that the thickness of the thin layer 11S might become predetermined.

Moreover, you may comprise so that the outside of each mold | die may be maintained at negative pressure, and the solvent component in a slurry may be forcibly sucked out of a mold | die while standing. In this way, the filling time can be further increased by shortening the standing time, directly removing bubbles in the slurry through the mold, and increasing suction.

After leaving for a predetermined time, the remaining 11th slurry is discharged inside the cylindrical body 17 and inside the thin layer 11S, and then the slurry is injected, left for a predetermined time, and discharged in the same manner as described above with respect to the 10th slurry. This is carried out up to the first slurry. Thus, when the slurry is injected from the 11th slurry to the 1st slurry, and left for a predetermined time and discharged repeatedly, as shown in FIG. 11, the powder of the slurry (alumina powder alone, alumina-tungsten mixed powder, tungsten) Single powder) is uniformly laminated in a laminated form, and the thin layers 11S, 10S, 9S,... From the wall surface side of the slurry injection space 13. , 1S is formed. Therefore, the molded body 20a which becomes the precursor thin layer of the obstruction body 2a is formed, respectively.

As is apparent from FIG. 12 showing the relationship between the volume ratio of tungsten and alumina of the thin layer, the composition distribution of the molded body 20a is gradually increased from the thin layer 1S as the center layer to the outer thin layer. As shown in b), the volume ratio of alumina is increased and inclined from 0% to 100%, and as in twelfth (a), the volume ratio of tungsten decreases from 100% to 0%. That is, the thin layer 2S in the molded body 20a corresponds to the innermost circumferential layer (or core portion side layer) of the laminate 20a of the above embodiment, and the thin layer 11S is the outermost circumference of the laminate 20. It corresponds to a layer (or bulb side layer), and the thin layers 3S to 10S correspond to respective intermediate layers (or intermediate layer) in the laminate 20. Therefore, the thin layers 2S to 10S are laminated materials laminated so as to cover the center layer 1S around the center layer 1S.

Thus, when injection, leaving for a predetermined time, and discharging are completed for each slurry, the coupling die 10 is divided to release the molded body 20a having the shape shown in FIG. 7, and when the solvent is completely removed from the molded body 20a. It is dried until (process 4).

Then, the molded body 21a is subjected to a heat treatment at 600 ° C for 10 hours under a humidified hydrogen atmosphere, and the molded body 20a is degreased and calcined (step 5). That is, by performing this heat processing, the dispersing agent mix | blended at the time of slurry preparation thermally decomposes and the molded object 20a is degreased.

Subsequently, as shown in FIG. 13, support holding holes 21a and 21b are provided at both ends of the molded body 20a after calcining, and the support holding holes provided at the front end of the center layer 1S ( The support shaft 4 supporting the main electrode 3 is fitted to 21a, and the tungsten shaft 5 is fitted to the support holding hole 21b to set the main electrode 3 (step 6). .

Subsequently, the molded body 20a is subjected to post-insulation treatment at 1500 ° C. for 2 hours in a vacuum atmosphere to the molded body 20a after the set of the main electrodes 3 (step 7) to obtain a closed body 2a as the sintered body. In addition, the carbides denatured during degreasing until the heat treatment is completed are completely burned off from the sintered body.

In this sintering process, each thin layer of the molded body 20a is integrated by solid phase bonding as in the case of the laminated body 20 of the above embodiment. In addition, the support shaft 4, the shaft 5, and the thin layer 1S are integrated by solid-phase joining by volume contraction and coexistence of tungsten by sintering. As a result, the obturator 2a obtained after sintering is firmly combined with the support shaft 4 and the shaft 5 supporting the main electrode 3 so that the support shaft 4, i.e., the main electrode 3 is hermetically sealed. Encapsulate and stick. Thus, the occlusion body 2a is completed, and all the manufacturing processes thereof are completed.

In addition, the outer diameter of the blockage body 2a obtained by sintering is determined by the diameter of the slurry injection space 13 based on the volume shrinkage at the time of sintering. Therefore, it is not necessary to perform outer circumferential processing.

In addition, the distribution of the thermal expansion rate from the support shaft 4 to the thin layer 10S via the thin layers 2S to 9S is determined by the composition distribution of the thermal expansion rate of the support shaft 4. It becomes inclined distribution until it reaches the thermal expansion rate (thermal expansion rate of alumina) of the light-emitting tube body 1F from (thermal expansion rate of tungsten).

The completed occlusion body 2a is attached to the electrode holding hole 1a of the light tube main body 1F as shown in FIG. 14, and the infrared or high output laser is localized over the contact range of the light tube main body 1F. Irradiated with intensive heating.

By this localized heating, the alumina in the thin layer 20S of the obturator 2a and the light emitting body main body 1F are solid-bonded. As a result, the obturator 2a and the light emitting tube main body 1F are hermetically fixed and encapsulate the starting rare gas metal and the discharge material. In this way, the light emitting tube shown in FIG. 14 is completed.

The lighting life of the light emitting tube using the obstructing body 2a was also measured, and the durability of the light emitting tube using the obstructing body 2 was measured. That is, even in the light emitting tube using the obturator 2a, the support shaft 4 having the main electrode 3 and the support shaft 4 or the light emitting tube main body 1F adjacent to the light emitting tube main body 1F have a thermal expansion coefficient. The thermal stress resistance can be improved by the obturator 2a inclined at the thermal expansion rate. As a result, since it is excellent in thermal stress resistance, light emission reliability can be raised and it can be long life. In addition, such a light emitting tube can be easily provided.

Furthermore, according to the light emitting tube using the obturator 2a, the following effects can be obtained.

In supporting the main electrode 3 disposed in the light emitting body 1F, the thin layer 11S exposed in the light emitting body 1F is made to have an alumina volume ratio of 100%, that is, an insulator. The occurrence of the back arc in the main electrode 3 can be avoided. As a result, a more stable lighting state can be obtained.

In addition, since the main electrode 3 and the external terminal shaft 5, which are indispensable at once, are commonly hermetically sealed by the thin layer (central layer) 1S having a tungsten volume ratio of 100%, the main electrode without any problems. A predetermined voltage can be applied to (3).

In addition, since the thin layers are formed by injecting each slurry, the thickness of each thin layer can be made uniform to ensure the inclination of the composition distribution and the thermal expansion rate over each layer.

As mentioned above, although two Example of this invention was described, this invention is not limited to such an Example, Of course, it can be implemented in various forms in the range which does not deviate from the summary of this invention.

Although alumina powder having a purity of 99.99 mol% or more is used as a raw material of the light emitting body main body 1F, the obturator 2, and the obturating body 2a, the practical light transmittance of the light emitting tube main body 1F obtained as a light emitting tube 380 is obtained. Linear transmittance with respect to a wavelength of ˜760 nm), and is not limited to such fine alumina powder.

For example, compounds containing oxides such as alumina, magnesium, zirconia, and yttria, nitrides such as aluminum nitride, and the like, as main components, which contain compounds (sintering aids, etc.) which suppress the growth of abnormal particles and further promote sintering. You may add and sinter and produce the light emitting body main body 1F. Then, the obturator 2 and the obstruction 2a may be produced using the same ceramic fine powder as the light emitting tube main body 1F. More specifically, the light-emitting tube main body 1F is made from fine alumina powder having a purity of 99.2 mol% and an average particle diameter of 0.3 to 1.0 μm, and at the same time, the alumina fine powder and tungsten fine powder are used to block the occlusion body (2) and the obturator ( 2a) may be produced.

In addition, although tungsten fine powder is used as a raw material of the obturator 2 and the obturator 2a, it is not limited to this, It can change according to the material of the support shaft 4 which is a core part. For example, when the support shaft 4 is made of niobium, a niobium fine powder may be used as a raw material for the obturator 2 and the obturator 2a.

In addition, of course, what kind of thing may be sufficient as the shape of a light-emitting tube main body. For example, the light emitting tube body 1F of the above embodiment does not have a large diameter electrode holding hole 1a and a small diameter electrode holding hole 1b at both ends thereof, but merely a cylindrical light emitting tube having both ends opened. The light-emitting tube body, etc., in which the main body and the pipe are curved may be used.

Particularly, in the manufacturing method of Example 1, in the forming of the laminate 20 on the outer circumference of the tungsten support shaft 4 supporting the main electrode 3, the application and drying of each mixed slurry were performed. Unlike these, the sheet drawn in advance from each mixed slurry can be produced, and it can be rolled up one by one from the high volume ratio of tungsten on the outer periphery of the support shaft 4 in order. In this case, it is preferable that the green sheets are laminated in such a manner that the joining surfaces of the green sheets of each layer are alternately disposed 180 degrees apart from the support shaft.

In the solid state joining of the occluders 2 and 2a with the light-emitting tube body 1F, the localized heating is performed over its contact range, but the vicinity of the support shaft 4 may be heated. Since the heat energy applied even in such heating is transmitted to the outermost circumferential layer of the obstructions 2 and 2a, the obstructions 2 and 2a and the light emitting body main body 1F can be solid-bonded. In addition, the sintering of the blocking bodies 2 and 2a may be performed in a state in which the blocking bodies 2 and 2a after degreasing are attached to the light emitting tube main body 1F.

In addition, in attaching the obturator 2 to the light emitting tube main body 1F, it was fitted to the electrode holding hole 1a, but may be designed as follows. That is, as shown in FIG. 15, the obturator 2 is joined at the open end of the light tube body 1F to contact the end surface of the light tube body 1F with the side surface of the outermost circumferential layer of the obstruction body 2. Let's do it. Then, the contact range is locally heated to solid-state bond the color body 2 and the light tube main body 1F at the cross section.

Incidentally, the degree of inclination of the volume ratio of alumina and tungsten of the mixed slurry is not limited to that shown in the above embodiment, and various degrees of inclination can be adopted.

It is also possible to produce the obturator 2 using an inclined functional material such that its composition ratio is changed linearly from the core side to the bulb side.

According to the first and second embodiments of the present invention, the following effects can be obtained.

In the light emitting tubes of Examples 1 and 2, the obturator that is solid-phase bonded to the opening of the light emitting tube main body formed of the light-transmissive ceramic is a multilayer laminate, and the light emitting tube main body side is formed at the innermost circumferential layer of the conductive core portion at the center thereof. The distribution of the thermal expansion rate until reaching the outermost circumferential layer is a distribution inclined from the thermal expansion rate of the conductive core portion to the thermal expansion rate of the light emitting tube body by the inclination of the composition ratio of each layer.

Therefore, the composition of each layer can be inclined to solidify and tightly bond each other, the obturator, and the light-emitting tube body tightly.

In addition, the concentration of thermal stress generated during lighting due to the inclined distribution of the thermal expansion coefficient can be alleviated to prevent the occurrence of cracking at the solid-state junction. As a result, reliability of light emission can be improved and its life can be extended while avoiding leakage of the encapsulation material in the light emitting tube.

The light emitting tube of this embodiment is provided with a light emitting tube body (bulb) of high purity translucent alumina having an average particle diameter of 1 µm or less and a maximum particle diameter of 2 µm or less. As a result, since the mechanical strength is improved over the temperature at the time of discharge at room temperature, the thickness of the light emitting tube can be thinned to 0.2 mm or less of about 1/3 compared with the conventional one.

In addition, since the grain boundary phase such as the spinel phase is hardly formed and the crystallite interface inside the crystal grain, which is the light scattering factor, is made small by a small particle diameter, light scattering between light and the light penetrating the wall of the main body of the light emitting tube is suppressed. And it has a high linear transmittance with respect to the light (visible light) of the wavelength of 380-760 nm. For this reason, the brightness | luminance of a high voltage discharge lamp using the light emitting tube for high brightness discharge lamps can be improved. That is, the amount of light transmitted through the light emitting tube for the high brightness discharge lamp when the light is incident on the light emitting tube for the high brightness discharge lamp suppresses the scattering of the light, which is almost equal to the light amount of the incident light to the light tube for the high brightness discharge lamp. In addition, the brightness can be further improved by thinning.

Furthermore, since the blockage is sintered and manufactured using this light-purity alumina, the durability of the light emitting tube as a whole can be improved by improving the mechanical strength of the blockage itself.

According to the method of manufacturing the light emitting tubes in Examples 1 and 2, a plurality of suspensions having different volume ratios are prepared in advance, and using the same, a laminated obstructed body having an oblique distribution of thermal expansion ratio can be easily prepared, and the occluded body and the light emission. The tube body can be solidly joined in a solid and airtight manner. That is, it is possible to easily manufacture a light emitting tube having high reliability and long life. In addition, the laminated obturator having the inclined distribution of thermal expansion may be produced by sintering each star and solid-bonded to the light emitting body.

In particular, according to the manufacturing method of the light emitting tube shown in Example 1, lamination is carried out in the order of high volume ratio of the conductive member components by a simple process such as coating, and the fine grains which are precursors of the laminated obstructed body having an inclined distribution of thermal expansion coefficient A laminated body can be manufactured easily.

In addition, a plurality of suspensions having different volume ratios are each formed in advance by green sheets, and are laminated in the order of high volume ratios of the conductive member (or core portion) components by a simple step of winding the green sheet, and inclined distribution of thermal expansion. The microcrystalline laminated body which is a precursor of laminated obstructive body can be manufactured easily.

In the manufacturing method of the light emitting tube of Example 2, the suspension is injected into the porous mold and the solvent is penetrated, and the excess suspension is discharged from the lower volume ratio of the conductive member (or core) component. By repeating a simple process, the thin layers can be laminated in the order of the volume ratio of the conductive member components to easily produce a micro-laminated laminate that is a precursor of the laminated occluded body having an oblique distribution of thermal expansion. Then, the thickness of each thin layer is made uniform to ensure the composition distribution and the inclination of the coefficient of thermal expansion of each layer.

In addition, a central layer capable of conduction with the outside can be formed in the innermost peripheral layer of the occluded body as a conductive member component, and a predetermined voltage of the main electrode can be applied without a problem through the central layer. .

Next, the structure and manufacturing method of the encapsulation portion of the light emitting tube according to the third embodiment of the present invention will be described with reference to FIGS.

16 is a cross-sectional view of the light emitting tube according to the third embodiment of the present invention, in particular the light emitting tube body or bulb encapsulated structure of the light emitting tube main body or bulb inserted into the outer cylinder of the metal vapor discharge lamp.

Openings 302 are formed at both ends of the bulb 301, and an end cap 303 is integrally attached to the opening end 302 as a closed body, and an electrode rod as a core of the closed body is attached to the end cap 303. Holds 304 through.

The bulb 301 is made of a light-transmissive polycrystalline alumina, and the electrode rod 304 is made of a W (tungsten) -based material such as W / Th having excellent resistance to a light emitting material. Each electrode 304 has a male screw portion 305 attached to the end cap 303 and a flange portion 306 abutting the outer end surface of the end cap 303, and the outside of the flange portion 306 is platinum sealed. An encapsulant 307 such as glass or glass is encapsulated, and an amalgam encapsulation hole 308 is formed in one electrode rod 304 again.

The post end cap 303 has a multilayer structure similarly to the above embodiment. That is, the end cap 303 is formed of a plurality of layers 303 ₁ , 303 ₂ ... According to the axial direction of the bulb 301. … (303 _n-1), by laminating (303 _n), is configured, the layer (bulb side yeokcheung) (303 _1), whose thermal expansion coefficient of the bulb 301 is joined to the opening end 302 of the bulb 301 The female threaded portion 309, which is substantially equal to the coefficient of thermal expansion of the translucent alumina, and the male threaded portion 305 of the electrode rod 304 is screwed to the outermost layer (core portion reversing layer) 303 _n . At the same time, the double layer 303 _n has a coefficient of thermal expansion substantially equal to that of the electrode rod 304. Furthermore, the layers (middle layers) 303 ₂ and 303 _n-1 interposed between the respective layers 303 ₁ and 303 _n have an outer layer whose thermal expansion coefficient is equal to the thermal expansion coefficient of the inner layer 303 ₁ . there is the mole fraction of each layer is adjusted so as to gradually change in the coefficient of thermal expansion of the (303 _n).

In addition, each layer gradually increases in thickness from the inner layer 303 ₁ toward the outer layer 303 _n . In this way, the stress caused by thermal expansion can be alleviated more effectively.

And other layers 303 ₁ except for the outer layer 303n. The gap 310 on the taper is formed between the 303 _n-1 and the electrode 304, and the layers 303 ₁ ... 303 _n-1 and electrode electrode 304 are not in contact with each other.

An example of the manufacturing method of the light emitting tube for metal vapor discharge lamps of the above structure is demonstrated below with reference to FIG. 17 and FIG.

First, the slip for manufacturing the end cap 303 is adjusted. In order to adjust the slip, as shown in FIG. 17, the container C ₁ ... As much as the number n of layers constituting the end cap 303. (C _n ) was prepared, the raw material powder was weighed so as to obtain a desired coefficient of thermal expansion, a predetermined amount of distilled water and a dispersant and a binder for commercial ceramic addition were added, and uniformly mixed by a ball milling treatment for 24 hours for each container (C). ₁ )… Slip (S ₁ ) every C _n . Adjust (S _n ).

Here, when the end cap 303 is composed of 11 layers in total, the composition ratio of the raw material powder of each slip is shown in Table 7 below. In addition, a composition ratio is weight% and the slip number of Table 7 corresponds to the number of each layer which comprises the end cap 303.

TABLE 7

Subsequently, as shown in FIG. 18 (a), a cylindrical die 312 is set on the plate or gypsum plate 311 made of a porous body, and the slip (S ₁ ) adjusted in the above process in the die 312 is set. )… (S _n ) is injected one by one to form a laminate. In addition, slip (S ₁ ). In the case of injecting (S _n ), water is removed to some extent from the injected slip so as not to be mixed with the slip already injected, and then the next slip is injected. In this case, the solvent in the slip penetrates into the plate 311.

In addition, as shown in FIG. 18B, when the slip is injected, the molding rod 313 is set in advance, or after the injection, the molding rod 313 is set, and the mold 312 is dried as it is. The end cap 303 in which the tapered through-hole 314 is formed as shown in Fig. 18 (c) is obtained by removing the laminate from Figs. The shape of the through hole 341 may be a staircase as shown in FIG. 18D.

On the other hand, the bulb 301 formed of pure alumina slip is prepared, and the end cap 3 is wetted and adhered to the end of the bulb 301 as shown in FIG. 18 (e) and dried again. In this state, the bulb 301 and the end cap 3 are wetted together and dried again. In this state, the bulb 3010 and the end cap 3 are in a microcrystalline state, and the bulb 1 does not become translucent.

Subsequently, the bulb 301 and the end cap 303 were degreased at 600 ° C. for 5 hours in a moisture-reducing hydrogen reducing atmosphere, and then sintered at 1300 ° C. for 5 hours in a dry hydrogen reducing atmosphere. HIP treatment in an argon atmosphere, followed by annealing treatment at 1150 ° C. in a dry hydrogen reduction atmosphere to obtain an integrated light transmitting bulb 301 and an end cap 303.

Then, the female thread portion 309 is formed by performing a screw cutting function in the hole 314 formed in the end cap 303, and inserting the electrode rod 304 to insert the male thread portion 305 of the electrode rod 304 into the end cap ( 303 is screwed to the female threaded portion 309, and finally, the platinum rod 307 is fixed and encapsulated with the electrode rod 304, and the hole 308 formed in one electrode rod 304 is placed again to provide a platinum pipe. The jig is used to seal the amalgam in the bulb 301 to complete the lamp.

In addition, although the example which sintered a bulb and an end cap was shown in the example of illustration, you may make it join, after extinguishing a bulb and an end cap, respectively. In this case, the bulb made of alumina is consistently degreased and sintered in the air, then subjected to HIP treatment, and then annealed in the air to obtain a light-transmissive alumina tube. In this case, the end cap is sintered as above, but HIP treatment and annealing treatment are not required. In addition, the bulb and the end cap can be bonded by laser heating at vacuum or 2000 ° C. or higher, or by alumina and glass having the same thermal expansion coefficient. As a glass material, the softening point melting glass of softening point 900 degreeC or more is preferable.

In addition to the slip casting, the doctor blade method and the injection molding method may be used as the molding method.

In the case of the doctor blade method, the adjusted slurry is molded into a desired tape thickness and integrated by thermocompression molding to obtain an end cap exhibiting an inclined function. The bulb is obtained by injection molding using the same slurry or by pouring into a mold to solidify it.

Similarly in the case of injection molding, in the case of the end cap, a plate having a desired thickness is molded, heated and bonded to each other, and then thermocompression-bonded to a bulb previously molded.

As described above, also in Example 3, the end cap for sealing the open end of the metal vapor discharge or the like has a multilayer structure, and the coefficient of thermal expansion of each layer is gradually changed from the bulb opening end side in contact with the bulb to the core part layer holding the electrode. Since the end cap itself functions as an inclined material, it is possible to effectively prevent breakage due to thermal expansion difference or leakage of metal vapor enclosed in the bulb.

19 shows an example in which a part of the third embodiment is changed. In this modification, the bulb 301 'is different from the bulb 301 shown in FIG. 16, and both ends of the bulb are not opened, and the cross section 301a is formed. Each end surface portion 301a is provided with a small opening about the large diameter of the tapered through hole 314 so that the electrode rod 304 can be inserted into the bulb. By the light emitting tube by this change, the same effect as Example 3 can be obtained.

Next, the light emitting tubes according to Example 4 and Example 5 of the present invention will be described with reference to FIGS. 20 to 27. FIG.

First, Fig. 20 shows a sectional view of the main parts of the light emitting tube according to the fourth embodiment that fits into an outer cylinder such as a metal vapor discharge lamp. In FIG. 20, the cylindrical bulb 401 is made of light-transmitting polycrystalline alumina of high purity (99.99% = 4N), and an electrode encapsulating portion 403 as a block is formed on the inner wall of both end openings 402 of the bulb 401. It is.

The electrode encapsulation portion 403 is formed using an alumina material having a lower purity (for example, 93 to 97%) than the bulb 401 serving as a light emitting portion, and further comprises a first layer 403a serving as a bulb side and a core serving side. It is a multilayer structure composed of two layers 403b. (It may be three or more floors which provided the intermediate station layer of the intermediate station mentioned above). Here, the first layer 403a on the inner wall surface side of the bulb 401 is, for example, 96% pure alumina, and the inner second layer 403b is formed of 93% pure alumina, respectively. Then, the electrode rod 404 serving as the core portion is inserted into the electrode sealing portion 403, and the bulb 401 is fitted with a cap 405 made of alumina through which the electrode rod 404 penetrates on the open end side thereof. The glass solder is melt-cooled between the branch portion 403 and the electrode rod 404, between the electrode rod 404 and the cap 405, between the bulb 401 and the end portion of the electrode encapsulation portion 403, and the cap 405. The sealing glass 406 is sealed.

In this case, the purity of the cap 405 is preferably the average value of the purity of the bulb 401 and the electrode sealing portion 403. In addition, the cap 405 may be omitted as needed.

Thus, by forming the electrode sealing portion 403 made of alumina material of lower purity than the bulb 401 in the opening of the bulb 401, since the grain boundary glass component of alumina ceramics is present on the inner wall of the electrode sealing portion 403, the sealing glass solder for sealing Adhesiveness with is good and sealability improves. In addition, generation of thermal stress is suppressed by using alumina having a different purity to give a composition gradient structure. An example of the manufacturing method of the ceramic light emitting tube of the above structure is demonstrated by FIG. 21 thru | or FIG.

First, the vessel 21 is also described as (C ₄₁₎ to the transparent alumina for high purity (4N or higher) to the alumina powder container (C _42), respectively prepare the low purity (in this case 93%) of alumina powder shown in. Low-purity alumina fine powder contains silica and magnesium as impurities, and it is preferable to select a material having similar sintering behavior.

Then, a predetermined amount of distilled water, a commercially available dispersant and a binder are added to the weighed powder, followed by ball milling for 24 hours to prepare slip for injection molding. Next, these slips are mixed in an appropriate amount to prepare slips of several species with different purity. These mixing is performed about 1 hour using a stirrer. The 22 degree container (C ₄₃₎ in a high purity (4N) alumina slip (S ₄₁₎ the container (C ₄₄₎ an alumina slip (S ₄₂₎ with a purity of 96% as shown in a purity of 93 to the container (C ₄₅₎ in the manner described Percent alumina slip (S ₄₃ ) is prepared respectively.

Then, the mask 412 masks the periphery of the slip inlet / outlet of the two divided porous bodies or the gypsum mold 411 (shown in cross section and plan view of only one mold) shown in FIGS. 23 (a) and 23 (b). First, as shown in FIG. 23 (c), the high-purity alumina slip S ₄₁ of the container C ₄₃ is flowed in, and it is left to stand for a predetermined time, whereby the high-purity alumina layer 413 is ground and discharged. .

Subsequently, as shown in FIG. 23 (d), one end of the gypsum mold 411 penetrates into the alumina slip (S42) having a purity of 96% so that only the encapsulation is performed, and as shown in FIG. 23 (e), high purity alumina The 96% alumina layer 414 is formed in the inner periphery of the layer 413, and in the same way, the 96% alumina layer 414 of purity is also formed in the other end part. Next, one end of the gypsum mold 411 is immersed in a purity of 93% alumina slip (S ₄₃ ) so as to be deposited only in the encapsulation part, and then a 93% alumina layer in the inner circumference of the 96% alumina layer 414 as shown in FIG. 23 (f). 415 is formed, and in the same manner, a 93% purity alumina layer 415 is formed at the other end thereof.

The firing of the bulb can be carried out by firing at 1350 ° C. for 6 hours in air by selecting a powder, and then performing hot hydrostatic heat treatment at 1000 atm in an argon atmosphere, 1350 ° C. for 2 hours. In this case, however, low-purity alumina is hardly sintered at this temperature in general, and the alumina purity of the innermost portion of the encapsulation portion should be 97% or more.

The molded article thus obtained is sintered at 1800 ° C. for 6 hours in a hydrogen reducing atmosphere to obtain a bulb 401 made of an electrode encapsulation 403 made of a light transmissive alumina layer and an encapsulation portion of a low purity alumina layer.

The inner diameter of the bulb 401 and the electrode encapsulating portion 403 obtained as described above and the outer circumferential processing of the light emitting portion are performed to produce a metal vapor discharge lamp or the like.

Next, the fifth embodiment will be described with reference to FIGS. 24 to 27 as a modification of the fourth embodiment. Also in Example 5, the electrode encapsulation portion 523 of the laminated structure made of low purity alumina is formed at both ends 522 of the bulb 521 made of high purity (99.99% = 4N) light-transmissive polycrystalline alumina, and the electrode encapsulation portion 523 is formed. Inserting the electrode rod 524 as a core part in the inside, capping the cap 525 made of alumina through which the electrode rod 524 penetrates to the outside of the electrode encapsulation portion 523, and the electrode encapsulation portion 523, the electrode rod 524 and The cap 525 is sealed in the sealing glass 526.

The electrode encapsulation portion 523 is formed using an alumina material having a lower purity (for example, 99 to 97%) than the bulb 521 serving as the light emitting portion, and is formed according to the axial direction of the bulb 521 or the electrode 524. It is set as the laminated structure which consists of one layer 523a, the 2nd layer 523b, and the 3rd layer 523c (4 or more layers may be sufficient). Further, the thickness is gradually increased from the first layer 523a toward the third layer 523c. As a result, the third layer 523c and the second layer 523b are adjacent to the electrode rod 524 that is larger in area than the first layer 523a. In addition, the cap 525 uses alumina having the same purity as that of the third layer 523c.

In addition, the cap 525 can be omitted as needed.

An example of a method for producing a ceramic light emitting tube having the above structure will be described with reference to FIGS. 25 to 27.

First, as in Example 4, a high-purity (more than 4N) alumina fine powder for light-transmissive alumina and a low-purity (here 93%) fine alumina powder were prepared, respectively, and a predetermined amount of distilled water, a commercially available dispersant and a binder were added to the weighed powder. , as indicated in claim 25 is also treated 24 hours ball mill container (C ₅₁₎ in a high purity (4N) the alumina slip (S ₅₁₎ the container (S ₅₂₎ the alumina slip (S ₅₂₎ with a purity of 97% in the container (C ₅₃₎ and each making an alumina slip (S ₅₄₎ with a purity of 93% in the alumina slip (S ₅₃₎ with a purity of 95% of the container ₍₅₄ C) to.

Then, as shown in Fig. 27 (a), a cylindrical mold 532, which fits the bulb outer diameter, is set on the porous plate or the plaster board 531, and a molding rod is formed in the center of the mold 532. 533 to establish, alumina slip of these type 532 and the alumina having a purity of 93% in the space formed by forming rod 533 slip (S _54), purity of 95% alumina slip (S _53), purity 97% ( S ₅₂ ) and the high purity alumina slip (S ₅₁ ) are sequentially injected to form a laminate. In addition, in the case of injecting slip, the slip which has already been injected is mixed with the slip that has already been injected to remove the water to some extent, and then the next slip is injected.

On the other hand, a pipe 534 made of a bulb 521 formed of a high purity alumina slip S ₅₁ as shown in FIG. 26 is prepared, and a high purity alumina slip S ₅₁ serving as an end 522a of the bulb 521 is prepared. ) Pipe (534) is integrated into the mold 532 in a state in which is not dried, to obtain a molded body shown in Fig. 27 (b). Then, in the same manner as in the above embodiment, the molded body is sintered, processed and assembled.

As described above, according to the present invention, an electrode encapsulation portion made of alumina material of lower purity than the light emitting portion is formed at both ends of the bulb, and the electrode encapsulation portion is brought into contact with the glass bulb or the encapsulating glass so as not to contact the electrode bulb. . Therefore, the reliability of the encapsulation is improved and the life of the lamp is extended.

In particular, as in the embodiment described above, the configuration of the electrode encapsulation portion is inclined so that the sealing effect of the encapsulation portion is further improved.

Next, the structure and the manufacturing method of the sealing part of the light emitting tube for metal electric discharge concerning Example 6 of this invention are demonstrated using FIG. 28 and FIG.

The bulb 601 as the light emitting tube shown in FIG. 28 is made of a light-transmissive polycrystalline alumina embedded in an outer layer such as a metal vapor discharge lamp. An alumina cap 604 as a closed body is fitted into the opening 602 of both ends of the bulb 601 via a sealing glass 603.

The cap 604 is made of a high purity alumina portion 604a, a composition inclined portion 604b and a low purity alumina portion 604c, and the high purity alumina portion 604a as the bulb side becomes Al ₂ O ₃ having a purity of 99.99% and a bulb. The low-purity alumina portion 604c serving as the core portion side station becomes 93.0% of Al ₂ O ₃ and outside the bulb 601, and the composition inclined portion 604b as the intermediate side portion has a high purity alumina portion 604a. ), The purity is 99.99% and the purity gradually decreases toward the low purity alumina portion 604c, and the portion in contact with the low purity alumina portion 604c is 93.0%. Thus, by setting a continuous composition gradient, peeling strength improves significantly. In particular, the low-purity alumina portion 604 has a larger width in the bulb sideline direction than the high-purity alumina portion 604a.

In addition, the cap 604 is provided with axial holes 605 and 606 as shown in FIG. 29 (d), an inner electrode 607 is formed in the hole 605, and an outer electrode is formed in the hole 606. (Lead) 608 is press-fitted. In addition, the diameters of the holes 605 and 606 are about 200 µm larger than the electrodes 607 and 608 after sintering. In this way, the cap is inhibited by the electrode during sintering and does not crack.

In addition, the low-purity alumina portion 604c is formed with a radial hole 609 communicating with the axial hole 605 from its side toward the inside, and the inner and low-purity alumina portion of the radial hole 609 thereof. On the outer circumferential surface of 604c, a conductive film 610 such as tungsten (W) is formed. The conductive film 610 has better conduction than the internal electrode 607 and the external electrode 608, and may be Nb, Ta, Mo, or Ni.

Next, an example of manufacturing the cap 604 will be described with reference to FIG. First, as shown in FIG. 29 (a), 100 g of high purity (99.99%) Al ₂ O ₃ and low purity (93.0%) Al ₂ O ₃ were each taken, followed by ball milling with 50 g of water and a peptizing agent for 24 hours. A high purity Al ₂ O ₃ slip (S ₆₁ ) and a low purity Al ₂ O ₃ (S ₆₂ ) are obtained.

Subsequently, as shown in FIG. 2 (b), the two types of slips S ₆₁ and S ₆₂ are mixed to prepare a plurality of types of slips S ₆₃ having a purity of 99.99% and 93.0%, and thereafter. As shown in FIG. 29 (c), a sintered cap (S ₆₁ ) is poured in order from a high-purity slip (S ₆₁ ) into a mold 615 set on a porous body or a plaster body 614, and is molded by one of the caps before firing. 616 is molded.

Then, the cap molded body 616 is calcined at 1100 ° C. for 2 hours to a hardness that can be handled, and the cap molded body 616 is then processed to show the axial holes 605 and 606 as shown in FIG. 29 (d). And laying the radial hole 609 in a cap shape and applying the conductive paste 610 to the inside of the radial hole 609 and the outer periphery of the low-purity alumina portion 604c. 3 hours at 1570 ° C. with the internal electrode 607 and the external electrode 608 inserted therein, and calcined under an atmosphere of N ₂ and H ₂ (N ₂ : H ₂ = 80: 20), as shown in FIG. 29 (c). Obtain the cap 604. The cap 604 is sealed to the opening 602 of the light emitting tube 601 with an insertion glass 603 or a low melting point alloy.

30 shows a method of partially modifying the manufacturing method of the light emitting body according to the sixth embodiment. In this manufacturing process, as shown in FIG. 30 (a), as shown in FIG. 30 (a), two porous or gypsum bodies 614a, 614b, and molds 615c, 615b are used. The molded body 616a of the same high purity alumina portion and the composition gradient portion and the molded body 616b of the low purity alumina portion are molded.

Subsequently, as shown in FIG. 3 (c), the conductive paste is applied to the surface of the molded body 616b, the conductive paste is applied to the surface of the molded body 616b by the conductive paste, and the molded body ( 616a is bonded and integrated, and then fired in the state where the internal electrode 607 and the external electrode 608 are inserted in the same manner as described above to obtain a cap 604 shown in FIG. 30 (b). In this case, since the conductive paste connecting the molded body 616a and the molded body 616b applies conduction between the internal electrode 607 and the external electrode 608, the radial holes 609 as shown in FIG. ) Is unnecessary.

As described above, according to the sixth embodiment, a high purity alumina portion in which the opening of the light emitting tube such as a metal vapor discharge lamp is closed and an inner electrode and an external electrode are separated and joined to the light emitting tube and a low purity alumina facing the outside of the light emitting tube It consists of a composition inclined portion connecting the high purity alumina portion and the low purity alumina portion from the portion, and forms a conductive film for conducting the internal electrode and the external electrode on the surface of the low purity alumina portion, so that the peel strength of the conductive film is increased from the conventional 1-4 kg / cm 2. It can improve to about 10 kg / cm <2>.

In addition, since the high purity alumina portion is formed in the light emitting tube, deterioration of lamp characteristics due to corrosion components such as Na can be suppressed, and since the conductive film is not formed in the high purity alumina portion and the composition gradient portion, back arc can be prevented. At the same time, metals such as Nb, Ta, Mo, or Ni can also be used as the conductive film (metallization).

[Industry availability]

According to the structure of the encapsulation portion of the light emitting tube of the present invention, it is possible to manufacture a light emitting tube for discharge lamp having high reliability and long life. In particular, it can be applied as a light emitting tube for metal vapor discharge lamps or high-brightness lamps, such as a mercury lamp, a metal halide lamp, or a sodium lamp.

Claims (50)

Understanding the obstructing body having the corpus constituting the electrode In the well-known structure of the light emitting panel encapsulating the opening end of the bulb, the composition component of the obturator is almost the same as the thermal expansion coefficient of this bulb in the bulb side adjacent to the opening end of the bulb. Component, which is almost the same as the thermal difference coefficient of the core portion in the core portion, and the component of the intermediate region between the bulb side region and the nose portion region adjacent to the core portion is the electrical core portion side region from the thermal expansion coefficient of the electric bulb side region. The composition ratio of the encapsulation portion of the light emitting tube is characterized in that the composition ratio is adjusted so as to change gradually with the coefficient of thermal expansion of the film. 2. The bulb side station and the electric core side station are separated by the intermediate station to form independent bulb side station and core side station layers, respectively, wherein the intermediate station is electrically thermally expanded from the bulb side station to the core side station. An encapsulation structure of a light emitting tube, characterized by comprising at least one or more layers whose coefficients are gradually changing. 3. The light emitting tube encapsulation structure according to claim 2, wherein the plurality of layers of the obturator are gradually increased in thickness from the bulb side layer to the core side layer. The structure of an encapsulation portion of a light emitting tube according to claim 1, wherein a metal vapor is enclosed in the light emitting tube. The encapsulation structure of a light emitting tube according to claim 1, wherein the obturator is made of a functional gradient material at least from the bulb side to the core side. The encapsulation structure of a light emitting tube according to claim 1, wherein the bulb is made of a light transmitting ceramic. 7. The light emitting tube encapsulation structure according to claim 6, wherein the bulb is a light transmissive alumina. The method of claim 7, wherein the bulb is a light-transmissive alumina sintered high purity alumina fine powder of 99.99 mol% or more, characterized in that the average particle diameter of the crystal grains of the light-transmissive alumina is 1㎛ or less and the maximum particle size is light-transmissive alumina of 2㎛ or less. The structure of the encapsulation part of the light emitting tube. 9. The light emitting tube encapsulation structure according to claim 8, wherein the component of the bulb side region is high purity alumina, the component of the core portion side is low purity, and the component of the intermediate region is compositionally inclined with respect to the purity of the alumina. . The composition of the bulb side region contains at least 80% of the light transmissive ceramic component in the volume ratio, and the composition component of the core side region contains the composition component of the core portion in volume ratio of at least 50%. The sealing part structure of the light emitting tube made into. 12. The component of claim 10, wherein the component of the intermediate region has a volume ratio of the transparent ceramic component so as to be inclined compositionally closer to the volume ratio of the translucent ceramic in the bulb side as the nearer to the bulb side region, and as the core portion becomes closer to the core side region. An encapsulation portion structure of a light emitting tube, characterized by having a volume ratio of the core portion composition component so as to be inclined close to the composition at a volume ratio with respect to the core portion composition component in the side region. 12. The encapsulation structure of a light emitting tube according to claim 11, wherein the light transmitting ceramic component contains high purity alumina and the composition component of the core portion contains tungsten. 13. The obstruction body according to claim 12, wherein the obturator has a support shaft for penetrating the obstruction and positioning the electrode inside the light emitting tube as a core, and at the same time, the outermost peripheral layer as the bulb side and the intermediate region as the intermediate region. And an innermost peripheral layer as the core part side region, and having at least three or more laminated bodies laminated on a concentric circle with the support shaft as a center. 13. The obturator according to claim 12, wherein the obturator has a support shaft for positioning and supporting the electrode inside the light emitting body, and has a core layer as a core part having a leading end portion connected to the support shaft as a core, and the outermost circumference as the bulb side region. A light emitting tube encapsulation portion structure comprising at least three or more laminates each containing a layer, a middle-zone layer as an intermediate station and an innermost circumferential layer as a core part side, and being laminated concentrically around the center layer. The encapsulation structure of a light emitting tube according to claim 13 or 14, wherein the bulb opening end and the outermost peripheral layer adjacent thereto are solid-phase bonded. 3. The method of claim 2, wherein the obturator has an electrode rod as a core portion for supporting the electrode to be positioned inside the electroluminescent tube through the obturator, and the bulb side layer is bonded to an opening end of the electric bulb. And at least one intermediate layer and at least one core portion side layer are sequentially stacked along the electric axis direction of the bulb. 17. The encapsulation portion structure of a light emitting tube according to claim 16, wherein the plurality of layers of the obstructing body gradually increases in thickness from the bulb side layer to the core side layer. 17. The encapsulation structure of a light emitting tube according to claim 16, wherein a gap is provided between the bulb side station layer, at least one intermediate station layer, and an electrode. 3. The obturator according to claim 2, wherein the obturator has an electrode rod as a core for supporting the electrode to be positioned inside the light emitting tube through the obturator, and has a bulb side resonant layer as the outermost periphery layer. An encapsulation structure of a light emitting tube, characterized in that the innermost layer is laminated concentrically around an electrode bar. 20. The encapsulation structure of a light emitting tube according to claim 19, wherein the innermost circumferential layer is laminated on an electric electrode bar through glass solder. 18. The method according to claim 17, wherein the core portion side layer and at least one or more intermediate portion layers are adjacent to the electrode rod in much larger area than the bulb side layer, and the bulb side layer, the at least one layer portion and the core portion side layer An encapsulation structure of a light emitting tube, wherein the light emitting tube is adjacent to the electrode through a glass solder. 3. The obturator of claim 2, wherein the obturator has a central electric core portion, and the bulb side layer, at least one intermediate layer and at least one core side layer are stacked along the axis direction of the core portion. The encapsulation structure of a light emitting tube, characterized in that adjacent to the bulb in the interior of the bulb. 23. The encapsulation structure of a light emitting tube according to claim 22, wherein said core portion side retardation layer is substantially larger in area relative to the electric core portion than at least one or more intermediate and reverse side layers. 24. The method of claim 23, wherein the core portion extends from the nasal layer to the electric bulb side layer, protrudes inside the bulb and has an internal electrode having an electrode at its tip, and an external electrode rod protruding outward from the core side side layer. The structure of the encapsulation part of the light emitting tube. 25. The encapsulation structure of a light emitting tube according to claim 24, wherein a conductive layer is formed on an outer circumferential surface of the core sublayer so as to achieve better electrical connection with the inner electrode and the outer electrode. 26. A core according to claim 25, wherein the core sublayer is provided with a through hole extending from the side circumferential surface of the core sublayer to an electric electrode. An encapsulation structure of a light emitting tube, characterized in that the electrical connection of the electrode is made. The light emitting tube encapsulation portion structure according to claim 25, wherein the obturator is bonded to an opening end of the bulb via the sealing glass. In the method of manufacturing a light emitting tube formed by sealing an open end of a light-transmissive bulb with a block having a core portion constituting an electrode, (a) based on the fine powder of the light-transmissive bulb component and the fine powder of the core-component, A bulb component suspension having a larger light transmissive bulb component than a core component, and a core component suspension having a larger core component than a light transmissive bulb component and at least one intermediate suspension between the two suspensions with respect to the composition ratio of the translucent bulb component and the core component; (B) a microbulb-bulb-measuring layer adjoining the light-transmissive bulb using the bulb component suspension and adjoining the core portion having the electrode using the core-component suspension; A core core side layer is formed and at least one intermediate string is formed between the bulb side side layer and the core side side layer. A method of manufacturing a light emitting tube comprising the step of forming a microcrystalline laminate by forming at least one or more intermediate reverse layers of microcrystalline using a suspension and (c) sintering the microcrystalline laminate. 29. The cavity of claim 28, wherein the step (b) comprises (d) a plurality of mold members made of a porous body joined to each other, and using a mold to form a cavity therein. Injecting the bulb component suspension, penetrating the solvent of the suspension into the electroforming mold, and then discharging the excess suspension to form an electric bulb side layer on the inner circumferential surface of the electrical cavity, and (e) then at least Forming a molded laminate by repeating injection, catalyst penetration and discharge treatment of one or more intermediate suspensions and the electric core component suspension on the inner circumferential surface of the electric bulb side-measuring layer in the same manner as in the case of the electric bulb component suspension; f) A method of manufacturing a light emitting tube, comprising: forming an electric non-stacked laminate comprising: separating each mold member constituting the electroforming mold and releasing the electroforming laminate. The process according to claim 29, wherein said step (e) injects a fine core suspension of fine core powder component onto the inner circumferential surface of the core portion retaining layer, and injects a solvent of the pure core suspension into the mold. And then discharging the extra pure suspension for the core portion to form the core portion layer in the electroformed laminate. 29. The electric process (b) according to claim 28, wherein the electric step (b) contacts the electric core part side retardation layer on the outer circumferential surface of the electric core part, and then sequentially at least one intermediate reverse layer and the electric bulb side retardation layer on the outer circumferential surface of the core part side retardation layer. And an electric step (c) includes a step of sintering the electric non-grained laminate laminated and ground in the core portion to form an electric occluder. 32. The method of claim 31, further comprising the step of disposing the obturator at an open end of the transparent bulb such that the electrode is located in the transparent bulb, and heating the solid-state junction between the obstruction and the light transmitting bulb. The manufacturing method of a light emitting tube. 29. The process according to claim 28, wherein the step (b) prepares each green sheet using a core component suspension, at least one intermediate suspension and the bulb component suspension, and the green sheet is in turn directed to the outer peripheral surface of the core portion. A method of manufacturing a light emitting tube, comprising the step of rolling to form an electric green layer laminate. 29. The composition of claim 28, wherein the bulb component suspension contains at least 80% of the light transmissive bulb component in an area ratio with respect to the core component, and the core component suspension contains at least 50% of the core component in volume ratio with respect to the electrotranslucent component. Method for producing a light tube, characterized in that. 29. The method of claim 28, wherein the bulb component is high purity alumina and the electrical core component is high purity tungsten. 29. The process (b) according to claim 28, wherein the step (b) uses (g) a mold formed by installing a cylindrical mold on a porous plate, in which the core suspension, the intermediate suspension, and the bulb component suspension are sequentially injected. And forming the coreless side layer, the intermediate side layer and the bulb side side layer to form an electric non-stacked laminate. 37. The light emitting device according to claim 36, wherein the step (g) includes a step of providing a tapered forming rod at the center of the moldability as a through hole for penetrating the core portion through the obturator. Method of making a tube. 37. The process according to claim 36, wherein the step (c) includes a step of forming a microbulb formed by fine powder of the light transmitting bulb component, and bonding the microstructured laminate to the open end of the microbulb bulb. Method for producing a light tube. The process according to claim 28, wherein the step (a) comprises preparing a pure bulb suspension from the fine powder of the light transmitting bulb component, and the step (b) is a cylindrical form comprising a plurality of porous bodies (h). After using the mold to inject the electric pure bulb suspension into the mold and ground it on the inner circumferential surface of the mold, it is immersed in the bulb component suspension, the intermediate suspension and the core suspension only at the end of the mold, and then used for the light transmitting bulb. And forming a layer, a bulb side layer, a middle side layer and a core side layer, wherein step (c) includes sintering a green laminate having a layer for the light-transmissive bulb. Method of making a tube. 40. The light emitting method according to claim 39, wherein the step (h) further includes a step of masking an end portion other than the inner circumferential surface of the mold before injecting an electrically pure ceramic component suspension into the mold made of the porous body. Method of making a tube. 37. The process according to claim 36, wherein said step (a) comprises the steps of preparing a pure ceramic component suspension from said translucent ceramic component, and forming a microbulb bulb body of a translucent bulb from said pure ceramic component suspension. The step (g) includes a step of integrating the green body bulb body on the bulb side layer of the green body laminate after forming the green body laminate formed of the core portion side layer, the intermediate layer and the bulb side layer. And said step (c) includes a step of sintering a laminate for sintering an electric non-grained laminate having the bulb-shaped hollow body. 29. The process (b) according to claim 28, wherein the step (b) comprises (i) forming a cylindrical mold on a plate made of a porous body, wherein the electric bulb component suspension, the intermediate suspension, and the core suspension are formed in the molding die. Injecting one by one, and forming a molded body comprising the bulb side station layer, the intermediate station layer, and the core side station layer. 43. The method according to claim 42, wherein the core portion is provided with an inner electrode rod and an outer electrode rod having electrodes at the tip, and the step (i) is a step of preparing a conductive paste, and after processing the molded body, A first hole extending from the bulb side station layer to the core part side station layer, a second hole extending in the lamination direction from the core part side station layer to the inside thereof in a stacking direction of the molded body, and a direction different from the stacking direction The core part side layer is provided with a third hole communicating with the first hole inward from the core part side reverse layer, the internal electrode is inserted through the first hole, and the external electrode is inserted into the second hole. Manufacturing a light emitting tube comprising covering the outer circumferential surface of the reverse layer with an electrically conductive paste and simultaneously filling the third hole with the conductive paste. Law. 29. The process (b) according to claim 28, wherein the step (b) uses a mold formed by installing a cylindrical mold on a plate made of a porous body, and injects a bulb component suspension and an intermediate suspension into the mold in order, and then the bulb side layer and A step of forming a first molded body made of an intermediate reverse layer, a step of forming a second molded body that is a single core part side-reduced layer in the core part suspension, and an outer circumferential surface of the second molded body covered with a conductive paste to form the first molded body. A method of manufacturing a light emitting tube, comprising the step of bonding to a molded body. In the encapsulation structure having the core constituting the electrode and sealing the opening end of the bulb by the obturator composed of the inclined functional material, the composition component of the electric occluder is thermally expanded in the core portion side adjacent to the core portion. An encapsulation structure of a light emitting tube, which is a component almost equal to a coefficient. A composition according to claim 45, wherein the composition component of the obturator is a component substantially equal to the thermal expansion coefficient of the bulb in the bulb side region adjacent to the opening end of the bulb, and in the core portion side region adjacent to the core portion, the core portion has a coefficient of thermal expansion. Is substantially the same as the component, and the composition ratio of the component in the intermediate region between the bulb side region and the core side region is gradually changed from the thermal expansion coefficient of the bulb side region to the thermal expansion coefficient of the core side region. The structure of the encapsulation of the tube. 47. The method according to claim 46, wherein the bulb side station and the core side station are separated by an intermediate station to form independent bulb side station layers and a core side station layer, respectively, wherein the intermediate station extends from the bulb side station to the core region. An encapsulation portion structure of a light emitting tube, characterized by being composed of at least one or more layers whose thermal expansion coefficients are gradually changing. 48. The encapsulation structure of a light emitting tube according to claim 47, wherein the plurality of layers of the obturator is gradually increased in thickness from the bulb side layer to the core side layer. 48. The encapsulation portion structure of a light emitting tube according to claim 46 or 47, wherein said occluders are stacked concentrically about said core portion. 47. The encapsulation portion structure of a light emitting tube according to claim 46, wherein a composition ratio of said obturator is linearly changed from said bulb side to said core portion side via said intermediate region.