DE380656C - Process for binding harmful gas residues in electric incandescent lamps through chemical compounds that are converted into desiccants when heated - Google Patents

Description

Process for binding harmful gas residues in electric light bulbs through chemical compounds that are converted into desiccants when heated. The subject matter of the invention is a method for binding harmful gas residues in electric incandescent lamps by introducing chemical compounds through Heating can be converted into desiccant.

It is known that even small amounts of water vapor in electrical Incandescent lamps have a detrimental effect on lamp life. this applies to both gas-filled lamps and vacuum lamps.

To remove water vapor and other harmful gas residues the lamps have been heated during manufacture and during evacuation desiccants are introduced into the light bulbs.

It has also been suggested to include metal compounds in the lamp to bring in that only when the light bulb is heated during manufacture chemical decomposition can be converted into desiccants, being particularly suitable Compound was called barium azide. In this process, the lamps became more common Way heated during purging by adding in the case of the use of barium azide Oxygen-containing gases could be admitted into the lamp for the purpose of forming Barium oxide. It has also been suggested that the decomposition of the barium azide be avoided from the start to let go in the presence of air. As an advantage of this procedure it was stated that the incandescent lamp was still equipped with a Desiccant was provided.

According to the invention, connections are also made in the incandescent lamp introduced, which change into desiccants through decomposition, but those which decompose required heating only takes place after the lamp has been evacuated. Preferably this heating takes place after the pump has melted the lamp.

As an example of a connection ,. «-Moose by heating in a desiccant can be converted, is called phosphorus suboxy d (P, 0), which itself as Desiccant is unusable, but when heated to about 25o ° C in phosphorus and phosphorus pentoxide is decomposed.

By the method according to the invention is manufacturing the lamps much easier. When pumping out the lamps, which ones are still contain non-decomposed compounds, they do not need to be heated to earth; on the contrary, it can be "pumped" at room temperature, whereas with the known ones Procedure to bring the lamp to a fairly high temperature when pumping out and this temperature had to be maintained until all noxious gases disappeared «-Aren.

oh your pumping and after the camping melted off the pump the lamps are heated to allow the decomposition of the active compound to take place allow; but this heating can take place much more easily than in the usual customary evacuation caps, which are completely omitted in the method according to the invention. There is also the possibility of the decomposition of the compound introduced at the same time with the heating, «-elche necessary for cementing the lamp base on the bulb is to run. A heating time of a few minutes is generally sufficient.

Pumping down the lamps can also be used in your method according to the invention take place very quickly because a high vacuum is not necessary. Harmful gas residues (Water vapor, etc.) are namely caused by the Bound desiccant.

The procedure after evacuating dry oxygen into the lamp to introduce is a complication which is completely avoided according to the invention will.

The desiccant also retains its full capacity with your new process hygroscopic effect in the already pumped-out lamp, while in the older one Process the desiccant part of this beneficial effect already during of pumping out loses.

Claims (1)

PATENT CLAIM: Process for binding harmful gas residues in electrical Incandescent lamps through chemical compounds that are converted into desiccants by heating are, characterized in that the decomposition of the compounds introduced by heating only after the lamp has not been evacuated.