DE202009013860U1 - halogen bulb - Google Patents

Abstract

Halogen incandescent lamp, with a luminous body, which is housed in a piston, wherein the bulb is a halogen-containing filling is housed, wherein the luminous body consists at least on the surface of a metal nitride or an alloy of metal nitrides, characterized in that the diameter of the bulb surrounding the bulb is at most 25 mm, wherein the operating pressure in the lamp is at least 2 bar and wherein the filling gas in addition to inert gas contains at least 0.1% nitrogen and wherein the filling gas contains at least one halogen from the group fluorine, chlorine, bromine, iodine.

Description

Technical area

The Invention is based on a halogen incandescent lamp according to the Preamble of claim 1. They are in particular for Operation at medium voltage to high voltage (HV) with typically 80 to 250 V thought.

State of the art

Of the Efficiency of thermal radiators is essentially determined by the temperature of the filament and the radiation selectivity for the visible area. To the efficiency of the conventional To increase thermal radiator with tungsten filament, one can to a material with a higher melting point than tungsten which use a higher temperature allow. Well-known examples of this are z. B. the refractory Carbides such as tantalum carbide, hafnium carbide, zirconium carbide, etc., or Alloys of these carbides. On the other hand, you can use materials which a larger part of the supplied electrical power as visible radiation instead of IR radiation radiate. Well-known examples of this are in addition to the already mentioned carbides, the nitrides of some transition metals such as Hafnium nitride and zirconium nitride. additionally go into the energy balance by the lamp design or Lamp design conditional losses, in particular heat dissipation over the filament ends and the filling gas, heat radiation the filament ends, losses in the power supply lines in the vacuum-tight Glass-to-metal transition, which in the following not further to be viewed as.

In US-A 5148080 The use of nitride illuminants is proposed to increase the efficiency of incandescent lamps. The proposal is to nitride luminescent bodies of hafnium or tantalum or hafnium-tantalum alloys, the metals being converted into nitrides by chemical reaction in a nitrogen-containing atmosphere. Since the melting points of the pure metals (eg hafnium: melting point 2227 ° C.) are significantly below those of the nitrides (eg hafnium nitride 3310 ° C.) or typical illuminant temperatures, nitration initially takes place at typically 1500 ° C. During nitriding, the temperature can be gradually increased. Characteristic of the thus obtained luminous body made of metal nitrides is that the metal nitride is substoichiometric - ie it contains less than 50 atom% N. Alternatively, the luminous body and a substrate -. Tungsten - on which hafnium, tantalum or alloys are deposited by known physical (eg PVD) or chemical (eg CVD) processes. The coating is then also nitrided.

Although the technically interesting nitrides such as HfN and ZrN have comparatively high melting points in the range around or above 3000 ° C. However, they decompose thermally even at significantly lower temperatures with release of nitrogen or evaporation of metal. In US 514080 It is described that the luminous body can be stabilized when it is operated in a nitrogen-containing atmosphere.

In GB 2124023 describes the coating of incandescent bodies with suspensions of nitrides (eg HfN, ZrN), which act as getters and stabilize the filaments.

In Proceedings of the ^8th International Symposium on the Science and Technology of Light Sources (LS-8) L. Bigio, "Investigation of HfN Coatings on tungsten for incandescent lamp efficacy improvement", p. 188-189, (1998) describes the use of HfN coated incandescent filaments in incandescent lamps. The HfN was deposited here on the filaments by the CVD method. By operating the filaments in pure nitrogen or in a nitrogen-containing atmosphere, the evaporation of the layer could be pushed far back. At cold filling pressures of less than 1 bar (600 Torr, typical filling pressure of incandescent lamps), the lifetime of a 3 μm-5 μm thick layer was determined to be 300 h to 500 h. The increase in efficiency was between 10% and 15%.

Presentation of the invention

The The object of the present invention is a halogen incandescent lamp to provide that achieves high efficiency.

These Task is solved by the characterizing features of claim 1.

Especially advantageous embodiments can be found in the dependent Claims.

the The procedure described here is based in particular on the object, the performance when using nitride coated luminaires to increase, d. H. in particular the life of the coating to increase.

This is achieved by the following essential features:
First, so far the operation of nitride-coated lamps has only been described in bulbs of incandescent lamps (operating pressure at about 1 bar or just above 1 bar). Of advantage, however, is the use of nitride-coated luminaires in flasks made of quartz glass, hard glass or ceramics, whose diameter corresponds to that of typical halogen lamps. Ie. he lies ahead given in the range below 25 mm, more preferably below 20 mm. This allows the use of significantly increased operating pressures. Typically, they are in the range above 2 bar, preferably in the range between 5 bar and 25 bar. Due to the higher operating pressure, the evaporation of the layer is drastically reduced by the significantly slower diffusion at higher pressures.

The higher the nitrogen partial pressure in the filling gas, the better the nitride layer is stabilized. When using higher total pressures, larger nitrogen partial pressures can be achieved without adversely affecting lamp quality by increasing the thermal conductivity or the transport rates. For example, a mixture corresponds to 90% Kr / 10% N ₂ at a total pressure of 1 bar a nitrogen partial pressure of 100 mbar. In a halogen lamp with an operating pressure of 8 bar 90% Kr / 10% N ₂ is obtained for a filling gas a nitrogen partial pressure of 800 mbar and thus a much better chemical stabilization of the layer due to the higher partial pressure. To realize a nitrogen partial pressure of 800 mbar at a total pressure of only 1 bar as in a conventional incandescent lamp one would have to use a gas mixture of 20% Kr and 80% N ₂ . However, this causes in the lamp due to the consequent large molar fraction of nitrogen in the law of mass action a significant increase in heat losses by conduction through the filling gas, and an increase in transport rates through the faster diffusion in nitrogen. In other words, an increase in the nitrogen content at constant total pressure, although a better chemical stabilization of the nitride coating, but on the other hand causes a significant reduction in efficiency due to the increased thermal conductivity, or acts by increasing the transport rates in the direction of accelerating the evaporation of the coating. Thus, in a conventional incandescent lamp with an operating pressure of about or just over 1 bar, the actually positive chemical effect of the increased nitrogen partial pressure is compensated in part by the described increased thermal conductivity or even u. U. overcompensated.

• – deutliche Verlangsamung der Schicht-Abdampfung durch verringerte Diffusionsgeschwindigkeit;
• – bessere chemische Stabilisierung der Nitrid-Schicht durch größere N2-Partialdrücke.

In summary, a higher total pressure, with the same composition of nitrogen-containing filling gas, has a positive effect in two respects:

• Significant slowdown of the layer evaporation by reduced diffusion rate;
• - Better chemical stabilization of the nitride layer by larger N2 partial pressures.

Secondly When using small piston diameters, the use of a Halogen addition to the filling gas required. This will prevents the deposition of metallic components on the piston wall. In addition, the halogen has added using suitable halogens or boundary conditions a regenerative effect in terms of Lifetime of the coating, d. H. it has a life-prolonging effect on the layer.

evaporated For example, from a zirconium nitride coating slowly zirconium aus, so this is converted near the piston wall in zirconium bromide, which - in contrast to zirconium - not on the piston wall fails. By the addition of halogen is so a failure of zirconium on the piston wall prevented. The zirconium bromide decomposes only at temperatures around or above about 2100 K to 2600 K, depending on the boundary conditions and halogen concentration. It will be in the corresponding temperature range deposited on the luminous body. In the temperature range from approx. 2100 K to approx. 2600 K this Zr-Br cycle process has thus a regenerative component, i. H. the halogen additive carries to extend the life of the coating. The evaporated Zirconium thus becomes at least partially within the appropriate temperature range transported back lighted luminous body. Together with the nitrogen from the filling gas forms again Zirconium nitride at the helical surface. Thus, that will evaporated zirconium via a circular process to the helix transported back, while the nitrogen directly from the filling gas as a reagent for nitriding available stands. So you do not need a cycle for the nitrogen component in the ZrN.

hydrogen in excess of the bromine concentration has a reducing effect on zirconium bromides in the temperature range between 1000K and 2500K. However, a blackening of the bulb is not to fear, because below 1000 K the reducing effect of hydrogen is severely limited. The regenerative Effect on the coating in the specified temperature range is but strongly weakened. The molar ratio of hydrogen: bromine should therefore preferably not exceed 5: 1.

Zirconium chlorides decompose at even higher temperatures than zirconium bromides. Thus, zirconium over the entire hot area of the filament up to temperatures of 2700 K to over 3000 K - depending on the chlorine concentration - increasingly released with increasing temperature. At typical luminaire body temperatures above 2600 K thus the zirconium-chlorine cycle has a significant regenerative component, ie by the targeted return of zirconium to the luminaire, combined with a nitration with the inclusion of nitrogen in the filling gas, the life of the coating can be significantly extended the. Hydrogen, although not strong, reduces zirconium chlorides in an average temperature range around 2000 K, and reduces the zirconium solubility in the gas phase in the range of 1500 K-2500 K. It thus provides - if the molar ratio of hydrogen: chlorine the ratio does not exceed 5: 1, to a weakening, but not suppression of the regenerative component of the cycle. For example, at a molar ratio of hydrogen: chlorine = 1: 1, the regenerative component of the cycle is still very strong.

analog Statements can be z. B. for the use of bromine or hafnium nitride-coated or hafnium nitride-chlorine derive existing luminous bodies.

ever after boundary conditions, the use of the other halogens is fluorine and iodine appropriate.

at the production of coated luminous body leaves The presence of oxygen with reasonable effort usually not completely exclude. The presence of oxygen in the nitride layers usually sets already at smaller concentrations in the range of a few atomic percent, the radiation selectivity clearly down in the visible, because the oxygen deposits a drastic increase in the emission coefficient in the IR effect. Here, the use of halogenated hydrocarbons affects advantageous because the carbon to a reduction of the oxides under formation of temperatures ranging from just under 1000 K to leads to over 4000 K of extremely stable carbon monoxide. In the case of oxygen inclusions, the addition of halogenated acts Hydrocarbons thus increasing efficiency. After extensive removal of the oxygen from the layer become small Amounts of carbon embedded in the coating, mostly only a few percent, often less than 2%.

In summary, based on the above statements, the use of halogenated hydrocarbons - as usual in "conventional" halogen lamps with tungsten filament - appropriate, ie z. As CH ₂ Br _2, CBr ₂ Cl _2, CH ₂ Cl 2, CCl _4, CHCl2Br, CHCl2I, etc.

In contrast to US 5148080 According to the invention, it is desirable to design the nitride coating as stoichiometrically as possible in order to achieve maximum increases in efficiency at least at the beginning of the service life. This is achievable z. B. by setting suitable parameters in the sputtering process.

The If possible, substrate should not react with the coating. Tungsten does not form at typical illuminant temperatures Nitrides, making nitride coatings on tungsten filaments are stable, d. H. that the tungsten of the coating is not nitrogen withdraws.

In a preferred embodiment, substrates of carbon, e.g. As carbon fibers, with a metal nitride, z. As hafnium nitride coated. Preferably, the carbon fiber is first coated with a metal carbide, then a metal nitride. As a result, the advantages of stabilizing the filament operated at high temperatures from the gas phase or from an inner depot can be combined. For the outer nitride coating, the stabilization takes place via the nitrogen in the filling gas, or via a metal-halogen cyclic process as described above. In this way, an at least partial regeneration of the coating is easier to implement than in the case of a carbide coating, in which the carbon must be transported back into the hot region of the luminous body as far as possible. The reaction systems suitable for regenerative recycling of the carbon - e.g. As the carbon-fluorine system - require extensive additional measures to their use, eg. B. Protection of the piston wall against attack by the fluorine. This can be omitted when using the nitride coating, because you can achieve at least partial regeneration of the layer without the use of fluorine. When the outer nitride coating finally evaporates, the outer metal carbide cladding acts as a radiation emitting surface. The evaporating outward carbon is - as in DE-A 10 2004 052044 described - replaced from the inside, using a means of transport - z. As hydrogen - transported to a functioning as a "sink" component in the lamp. For example, a failure of the carbon can be prevented at the piston wall by hydrogen, wherein the forming hydrocarbons decompose on the frame or the Wendelabgängen with deposition of carbon.

• (a) Stabilisierung der Nitrid-Beschichtung über einen hohen Stickstoff-Partialdruck im Füllgas bzw. einen Metall-Halogen-Kreisprozess mit regenerativer Komponente und
• (b) Stabilisierung der Carbidbeschichtung aus einem inneren Depot heraus.

The advantage of the proposed design lies in the combined use of the two life-prolonging features:

• (A) stabilization of the nitride coating via a high nitrogen partial pressure in the filling gas or a metal-halogen cycle process with regenerative component and
• (b) stabilizing the carbide coating from an inner depot.

Analogous It is also possible to coat boron nitride fibers with metal nitrides.

For the coating of the substrates with metals (which are then nitrated) or nitrides, all common coating methods are suitable. z. As CVD and PVD process, pasting, electrolytic deposition, etc.

It can also be completely made of metals such. B. Zirconium, hafnium, tantalum, niobium or titanium existing luminous bodies by heating in a nitrogen-containing gas atmosphere be nitrided. So z. B. filaments Zirconium nitride are manufactured.

The By the procedure described achieved slowdown of Layer evaporation can be used if needed, the temperature of the luminous element and thus increase the efficiency to increase.

• (1) Betriebsdrücken von deutlich über 1 bar unter Verwendung von Stickstoff enthaltenden Füllgasen und
• (2) der Verwendung von Halogenzusätzen zum Füllgas,

die Effizienz sowie die Lebensdauer einer Lampe mit Leuchtkörper mit Nitrid-Beschichtung gegenüber dem bisherigen Stand der Technik deutlich steigern lassen, bzw. eine Abscheidung von Feststoffen an der Kolbenwand vermeiden lässt.In summary, it can be stated that the use of

• (1) operating pressures well above 1 bar using nitrogen-containing filler gases and
• (2) the use of halogen additives to fill gas,

can significantly increase the efficiency and the life of a lamp with luminous body with nitride coating over the prior art, and can prevent deposition of solids on the piston wall.

Usually In inert gas noble gases are used as inert gases. The heavier the noble gas, the higher the efficiency given life, because both the thermal conductivity as well as the diffusion coefficient with increasing mass of the noble gas lose weight. Ie. the heavier the noble gas, the lower the heat losses over it filling gas; and the slower the unwanted occurs Evaporation of material from the lamp. Pure nitrogen is because of its great thermal conductivity or because of the fast in him transport processes usually not used in incandescent or halogen lamps. was standing The technique is the addition of nitrogen to a noble gas to electric To avoid breakdown inside the lamp. As the nitrogen itself negatively affected the lamp quality as mentioned above (i.e. H. Efficiency at a constant lifetime), one strives to keep the nitrogen content as low as possible. So is the nitrogen content in (halogen) incandescent lamps is practical always less than 20%, preferably less than 15%, and especially preferably less than 10%. In each case causes an increase The nitrogen concentration is a decrease in the transport processes certain lamp quality.

deviant Of these, the nitrogen in lamps with luminous body with Nitride coating an additional, the lamp quality increasing effect. The higher the nitrogen partial pressure, the lower is - as described above - the Evaporation of the nitride coating from the luminous body. this leads to to do that when increasing the nitrogen concentration the lamp quality increased. At an increase Nitrogen concentration thus outweighs the reduction the equilibrium pressure over the lamp the assumption of efficiency through increased heat dissipation as well as the increased diffusion speed. Only with a drastic increase in the nitrogen content decreases the lamp quality due to the effects described above again. While the lamp quality of lamps with Mantle made of pure tungsten so with increasing nitrogen content monotonically falling, it exhibits nitride coated lamps Illuminant to a maximum.

ever heavier the noble gas, the lower the nitrogen contents this maximum. This is due to, that naturally the lamp quality decreasing properties of nitrogen all the more work out, the greater the differences in quality when operating in pure noble gas or in pure nitrogen.

at typical operating pressures in the range between 5 bar and 10 bar is for lamps with nitride, in particular HfN coated Illuminant, the optimal nitrogen content for Lamps with xenon as inert gas between 10% and 40%, for Lamps with krypton as inert gas between 15% and 50%. The optimal Nitrogen levels are thus greater than those the state today when using nitrogen for suppression of electrical breakdown are common.

As high concretely, the nitrogen content within the specified ranges is chosen depends on further boundary conditions off, z. B. the proportion of power losses over the coil ends; this determines how much heat loss over the filling gas fall into the weight. For cost reasons the use of larger nitrogen contents is advisable. Do you have to limit the temperatures at the piston or the contacts, are filling gases with smaller nitrogen contents and thus to prefer lower heat dissipation.

Especially promising is the coating of tungsten coils alternatives are instead of W, the materials Re, Os, or alloys Os, Re, W.

A Alternative as filaments are coated with nitride C-fibers.

The nitride materials mentioned, with which the coils are coated, are strong getters for oxygen. As mentioned already leads a ge only Storage of oxygen destroys the radiation selectivity in the visible. A complete avoidance of oxidation of the nitride coating in the lamp construction is difficult. Therefore, the fill gas should contain components that can reduce the metal oxides (eg, HfO ₂ and ZrO ₂ ). Hydrogen and phosphorus - as known from lamps with tungsten filament - are not suitable for this purpose. By contrast, carbon reduces metal oxides.

While lamps with a tungsten filament usually tend to use halogen additives with the lowest possible carbon content (to avoid embrittlement of the filament), lamps with a luminous element made of nitride or with nitride coating also have halogen additives with a relatively high content Carbon content into consideration, z. As halogenated, unsaturated aliphatic and aromatic carbon compounds such as C ₂ Cl ₂ , C ₂ Br ₂ , C ₆ Cl ₆ .

The addition of further carbon-containing compounds may be appropriate. The aim should be to bring as few additional disturbing elements into the lamp. For example, when methane (CH ₄ ) is added, hydrogen is introduced into the lamp. However, too much hydrogen in the lamp atmosphere adversely affects the metal-halogen cycle process and results in a reduction in efficiency through increased heat dissipation. It is expedient for a removal of oxygen radicals in the nitrides z. As the use of compounds such as cyanogen (CN) ₂ or acetonitrile CH ₃ CN. By using these compounds, no or only very little hydrogen is entered into the lamp atmosphere. The cyanogen radical released upon decomposition of these compounds only reacts with the oxygen from the metal oxides to form CO at the high temperatures of the luminous body. As a result, the carbon is very selectively released where it is needed. The nitrogen produced by the decomposition of CN does not bother us anyway.

expedient is the reduction of metal oxides before pumping and filling the lamp. For this purpose, at least on the surface hafnium, tantalum, Zirconium, niobium or their nitrides containing luminous body in an atmosphere of a noble gas or nitrogen, which small amounts of a carbon-containing compound were added to temperatures typically in the range between 1000 K and 3000 K (depending on the melting point or vapor pressure of the metal or the compound) is heated. Suitable as carbon-containing compounds For example, hydrocarbons such as methane. Here are the in the Metal or metal nitrides embedded metal oxides reduced, whereby carbon monoxide arises. The thereby occurring to a small extent Carburization can be accepted.

at low temperatures, such as occur near the pinch The reduction of metal oxides by carbon does not work more. This does not bother, because this area is convenient no radiation emitted. On the contrary, this getter effect of the metal near the pinch, because so otherwise disturbing oxygen can be bound there.

Brief description of the drawings

in the The invention is based on several embodiments be explained in more detail. The figures show:

1 an incandescent lamp with carbide filament according to an embodiment;

2 a first embodiment of a filament for the incandescent lamp according to 1 on average;

3 A second embodiment of a filament for the incandescent lamp according to 1 on average;

4 the ratio of the emissivity of HfN and ZrN relative to W as a function of wavelength;

5 the vapor pressure of Hf as a function of temperature for different fillings.

Preferred embodiment the invention

1 shows a bulb squeezed on one side 1 with a quartz glass bulb 2 , a bruise 3 , and internal power supplies 6 , the slides 4 in the bruise 3 with a luminous body 7 connect. The filament is a simple coiled, axially arranged wire of TaC as a carrier material whose uncoiled ends 14 are continued transversely to the lamp axis. The outer leads 5 are outside on the slides 4 stated. The inner diameter of the piston is 5 mm. The power supply lines 6 are either separate parts of Mo, W, or Ta or they are integrally continued as uncoiled ends of the filament.

The ZrN existing filament of schematically in 1 The lamp shown, whose basic design corresponds largely to a low-voltage halogen incandescent lamp available on the market, has been produced by nitriding and has a power consumption of approximately 40 W when operated at 13 V, whereby the color temperature is characteristically around 3500 K.

In 2 is schematically another embodiment of a filament 7 shown in more detail. In cross-section, it has a carrier material 20 out of W, which forms the core. The typical diameter is 20 to 200 μm. There is a layer on it 21 applied, which consists of a mixture HfN / NbN.

In 3 is schematically another embodiment of a filament 7 shown in more detail. In cross-section, it has a carrier material 20 made of carbon fibers, which forms the core. The typical diameter is 80 to 120 μm. On it is a first layer 22 applied, which consists of ZrC or HfC or a mixture thereof, the thickness is about 3 microns. There is a second layer on it 23 made of ZrN whose thickness is about 2 microns. Preferably, the layer thicknesses should not exceed 5 microns per layer, otherwise there is a risk of spalling.

A concrete embodiment is a halogen lamp for operation on mains voltage (ie 100 V-240 V) in Noppentechnik. The coil consisting of tungsten was first coated with 2 μm zirconium. By reaction in a nitrogen-containing atmosphere in the temperature range between 1200 ° C and 1800 ° C, the zirconium is first converted to zirconium nitride. Directly at the spiral holder or at the pinch edge 15 (please refer 1 ), the temperatures for nitriding are too low, so that here - if not removed by the crushing process - still present metallic zirconium. This has an advantageous effect over the life as a getter. The lamp is filled with 5 bar Xe / N ₂ 80% / 20% as well as a halogen additive of 500 ppm CH ₂ Br ₂ .

Another specific embodiment is a low-voltage lamp (NV halogen lamp). In a CVD process, the tungsten filament was coated with hafnium nitride; the layer thickness is 5 μm. The lamp is charged with 7 bar Kr / N2 80% / 20% + 700 ppm CH ₂ Cl ₂ . Alternatively, CCl2BrH is used.

Analogously, the lamps can be designed in frame technology, or the luminous bodies of nitride or nitride coating can in lamps with IR reflective coating 16 (please refer 1 ) are used on the lamp bulb. Especially when using the luminous elements together with the IRC technique, the use of a halogen additive in the filling gas is required to avoid a rapid piston blackening occurring at the typically small piston diameters.

One Another embodiment is one with ZrN (layer thickness 4 μm) coated 12 V 50 W tungsten filament. The coating looks golden. Since the zirconium nitride on a stable Substrate is located, the problem of brittleness is bypassed. The increase in efficiency over an uncoated one Wendel is between 10% and 20%.

The importance of halogen addition clarifies the following experiment:
A luminous element with ZrN coating (sputtered) is operated with a filling 5 bar Kr / N ₂ 88/12, 700 ppm CH ₂ Br ₂ or alternatively without addition of halogen. After 50 hours, the coating is intact in the case of the halogen-containing filling, while in the filling without halogen addition, the coating has largely evaporated. The efficiency gain with ZrN coating is about 10%.

The emissivities of HfN and ZrN compared to tungsten shows 4 , Here it can be seen that in the visible the radiation fraction for the nitrides is significantly higher than for W.

By using a nitrogen-containing gas filling, the HfN layer can be stabilized. Without N2, the HfN would be at high temperatures according to the equation HfN → Hf + 1 / 2N 2 disintegrated. The thermodynamic calculation of Hf vapor pressure over HfN using Xe / N ₂ mixtures shows 5 , Possible additional kinetic factors are not taken into consideration.

As expected, the higher the nitrogen partial pressure over the HfN surface, the better the stabilization of the HfN layer. The vapor pressure curves for 1 bar 100% N ₂ and 9 bar Xe / N ₂ 99/10 are almost on top of each other, because the nitrogen partial pressures are almost identical (1 bar 100% N ₂ : = 1000 mbar N ₂ , 9 bar Xe / N ₂ 90 / 10: = 900 mbar N2).

• (1) Höherer Partialdruck der N-Atome bei gleicher Gaszusammensetzung; dies führt zur schnelleren Rückreaktion zu HfN.
• (2) Viel geringere Abdiffusion des Hf wegen höheren Drucks.
• (3) Die Verwendung von Xe statt Ar wird wirtschaftlich. Damit ergeben sich viel geringere Abdampfraten in Halogenlampen.

HfN coated coils are known in conventional incandescent lamps. In contrast, the use of HfN-coated coils in halogen lamps offers significant advantages using a much higher operating pressure:

• (1) Higher partial pressure of the N atoms with the same gas composition; this leads to a faster reversion to HfN.
• (2) Much lower diffusion of Hf due to higher pressure.
• (3) The use of Xe instead of Ar becomes economical. This results in much lower evaporation rates in halogen lamps.

• 1. Halogenglühlampe, mit einem Leuchtkörper, der in einem Kolben untergebracht ist, wobei im Kolben eine halogenhaltige Füllung untergebracht ist, wobei der Leuchtkörper zumindest an der Oberfläche aus einem Metallnitrid oder einer Legierung von Metallnitriden besteht, dadurch gekennzeichnet, dass der Durchmesser des den Leuchtkörper umgebenden Kolbens höchstens 25 mm beträgt, wobei der Betriebsdruck in der Lampe mindestens 2 bar beträgt und wobei das Füllgas neben Edelgas mindestens 0,1% Stickstoff enthält und wobei das Füllgas mindestens ein Halogen aus der Gruppe Fluor, Chlor, Brom, Jod enthält.
• 2. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der Leuchtkörper aus beschichtetem Substrat besteht, wobei das Substrat ausgewählt ist aus den Materialien W, Ta, Re, Os, C, Bornitrid oder Legierungen dieser Stoffe, und wobei die Beschichtung ausgewählt ist aus den Materialien HfN, ZrN, TaN, TiN, NbN, AlN, Bornitrid oder Legierung dieser Nitride.
• 3. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der Leuchtkörper vollständig aus einem Nitrid des Hf, Zr, Ta, Nb, Ti; Al, B bzw. einer Legierung von Nitriden besteht.
• 4. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der halogenhaltige Zusatz zum Füllgas Halogen und Wasserstoff enthält, wobei das molare Verhältnis Wasserstoff:Halogen < 5 ist.
• 5. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der halogenhaltige Zusatz zum Füllgas Brom und/oder Chor enthält, und dabei im wesentlichen frei von Wasserstoff ist.
• 6. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass die Füllung zusätzlich Kohlenstoff neben dem Halogen und ggf. dem Wasserstoff enthält.
• 7. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der Leuchtkörper aus Kohlenstoff besteht, der zuerst mit einem Metallcarbid, dann mit einem Metallnitrid beschichtet ist.
• 8. Halogenglühlampe nach Anspruch 2, dadurch gekennzeichnet, dass der Kolben mit einem IR-reflektierenden Material beschichtet ist.
• 9. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass die Füllung halogenierte Kohlenwasserstoffe enthält.
• 10. Halogenglühlampe nach Anspruch 1, dadurch gekennzeichnet, dass der Anteil des N2 zwischen 5 und 20% beträgt, Randwerte eingeschlossen.

Essential features of the invention in the form of a numbered list are:

• 1. halogen incandescent lamp, with a luminous body, which is housed in a piston, wherein in the flask, a halogen-containing filling is housed, wherein the luminous body is at least on the surface of a metal nitride or an alloy of metal nitrides, characterized GE indicates that the diameter of the piston surrounding the luminous element is at most 25 mm, the operating pressure in the lamp being at least 2 bar and the filling gas containing at least 0.1% nitrogen in addition to noble gas and the filling gas being at least one halogen from the group consisting of fluorine, Chlorine, bromine, iodine.
• 2. Halogen incandescent lamp according to claim 1, characterized in that the luminous body consists of coated substrate, wherein the substrate is selected from the materials W, Ta, Re, Os, C, boron nitride or alloys of these substances, and wherein the coating is selected from the Materials HfN, ZrN, TaN, TiN, NbN, AlN, boron nitride or alloy of these nitrides.
• 3. Halogen incandescent lamp according to claim 1, characterized in that the luminous body made entirely of a nitride of Hf, Zr, Ta, Nb, Ti; Al, B or an alloy of nitrides.
• 4. Halogen incandescent lamp according to claim 1, characterized in that the halogen-containing additive to the filling gas contains halogen and hydrogen, wherein the molar ratio of hydrogen: halogen <5.
• 5. Halogen incandescent lamp according to claim 1, characterized in that the halogen-containing additive to the filling gas contains bromine and / or chlorine, and is substantially free of hydrogen.
• 6. Halogen incandescent lamp according to claim 1, characterized in that the filling additionally contains carbon in addition to the halogen and optionally the hydrogen.
• 7. Halogen incandescent lamp according to claim 1, characterized in that the luminous body consists of carbon, which is first coated with a metal carbide, then with a metal nitride.
• 8. Halogen incandescent lamp according to claim 2, characterized in that the piston is coated with an IR-reflecting material.
• 9. Halogen incandescent lamp according to claim 1, characterized in that the filling contains halogenated hydrocarbons.
• 10. Halogen incandescent lamp according to claim 1, characterized in that the proportion of N2 is between 5 and 20%, including boundary values.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 5148080 A [0003]
• US 514080 [0004]
• GB 2124023 [0005]
• US 5148080 [0022]
• - DE 102004052044 A [0024]

Cited non-patent literature

• - L. Bigio, "Investigation of HfN coatings on tungsten for incandescent lamp efficacy improvement", p. 188-189, (1998) [0006]

Claims (10)

Halogen incandescent lamp, with a luminous body, which is accommodated in a piston, wherein in the piston a halogen-containing filling is housed, wherein the luminous body consists at least on the surface of a metal nitride or an alloy of metal nitrides, characterized in that the diameter of the surrounding bulb surrounding the bulb is at most 25 mm, wherein the operating pressure in the lamp is at least 2 bar and wherein the filling gas in addition to inert gas contains at least 0.1% nitrogen and wherein the filling gas contains at least one halogen from the group fluorine, chlorine, bromine, iodine. Halogen incandescent lamp according to claim 1, characterized the luminous body consists of a coated substrate, wherein the substrate is selected from the materials W, Ta, Re, Os, C, boron nitride or alloys of these substances, and wherein the Coating is selected from the materials HfN, ZrN, TaN, TiN, NbN, AlN, boron nitride or alloy of these nitrides. Halogen incandescent lamp according to claim 1, characterized that the filament is completely made of a nitride of Hf, Zr, Ta, Nb, Ti; Al, B or an alloy of nitrides consists. Halogen incandescent lamp according to claim 1, characterized that the halogen-containing addition to the filling gas halogen and Contains hydrogen, the molar ratio Hydrogen: halogen <5 is. Halogen incandescent lamp according to claim 1, characterized that the halogen-containing addition to the filling gas bromine and / or Contains chorus, while essentially free of hydrogen is. Halogen incandescent lamp according to claim 1, characterized that the filling in addition to carbon the halogen and optionally the hydrogen. Halogen incandescent lamp according to claim 1, characterized that the filament is made of carbon, the first coated with a metal carbide, then with a metal nitride is. Halogen incandescent lamp according to claim 2, characterized that the piston is coated with an IR-reflective material is. Halogen incandescent lamp according to claim 1, characterized that the filling contains halogenated hydrocarbons. Halogen incandescent lamp according to claim 1, characterized characterized in that the proportion of N2 is between 5 and 20%, Boundary values included.