DE3101128C2 - Getter body and process for its production - Google Patents

Abstract

The getter body consists of a powder mixture which, in addition to the actual getter material, also contains aluminum stearate, plastic and water glass. The getter body is obtained by first pulverizing a mixture of getter material and hydrogen and adding the plastic and aluminum stearate to this mixture.

Description

The invention relates like the main patent (DE-PS 30 08 290) on a getter body for use in encapsulated electrical components in the form of a Compressed tablet with an essential component of a getter substance known per se, such as activated carbon, Zeolite or the like, the getter body being made from a Puker mixture with a proportion of up to 70% by weight of the getter material. consists of about 10% aluminum stearate and a remainder containing plastic. aside from that the invention relates to a method for producing such a getter body.

Getter tablets for use in electrical components must have the largest possible porous surface own. However, precisely in the porous consistency of the getter materials there is also the disadvantage that the Getter materials tend to crumble. In particular when the component is vibrated the risk that dust particles of the getter material get to the contacts and there contamination of the Cause contact surfaces, e.g. on relays. To the main patent is therefore already proposed.

to bind the getter material with aluminum stearate and a remainder with plastic to make the getter tablets to make largely abrasion-resistant. This mentioned remainder in the main patent consists entirely of Plastic, preferably partly made of polyamide and partly made of polycarbonate To bind the Getter material is this as a powder first in a synthetic material solution, preferably in a polycarbonate solution introduced and then processed such plastic solutions have the disadvantage that they work with methylene chloride or similar compositions, not only soft during processing an odor nuisance, but also a health hazard for those involved because of its toxicity Representing people.

The task of the present additional invention is therefore the composition and the manufacturing process of the getter body mentioned at the beginning, to be changed so that the positive properties of this getter body, especially its absorption capacity at the same time good abrasion resistance, fully retained, but that the unpleasant and hazardous to health Accompanying circumstances in the production are reduced.

According to the invention, this object is achieved in that the plastic-containing residue in addition to plastic contains a proportion of potassium-sodium-silicate. With the addition of plastics, potassium-sodium-silicate and aluminum stearate to the getter material, is guaranteed

jo sta that the pressed getter tablets are largely abrasion-resistant are. They can be made in any geometric shape by pressing the powdery mixture will. Just like the getter bodies, they can be passed on to the main godparent without any problems as bulk goods.

j5 processed and used in a wide variety of components without the function of the component being disturbed by crumbling particles. The remainder off Plastic and potassium-sodium-silicate can be between 20 and 80% by weight vary: expediently, the The remainder itself consists of about 10% by weight of potassium-sodium silicate and about 90% by weight of polyamide.

An advantageous process for the production of the getter body according to the invention consists in analogy to the main patent that first the getter substance is introduced in powder form into water glass to form a first mixture, that this mixture is dried and ground again to powder, that the powder of the first mixture is mixed with polyamide powder and aluminum stearate is mixed to form a second mixture and that the tablets are finally pressed from this second mixture. Suitably it is wide in to dry the second mixture before itm pressing of the tablets, which can be done by heating to a temperature of about 60 C ^3.

In a further analogy to the main patent, the pressed tablets are advantageously hardened in a further process step, namely at temperatures of about 200 ^° C. In addition, it is still

bo expediently, the finished getter body after firing or hardening to trovalize in order to remove burrs or non-adherent particles from the surface remove and separate getter bodies adhering to one another. 7. For this purpose, triangular stones can be put together with the getter bodies and with water are added to the drum.

The getter bodies obtained in this way have, like the corresponding getter bodies of the main patent, very good ones

31 Ol 128

abrasion-resistant surfaces without any significant loss of getter effect. In the usual way the getter body by excavating in front of or activated after installation in the relevant Bauelsment.

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Claims (7)

31 Ol 128 claims: 1. Getter body for use in encapsulated electrical components in the form of a compressed tablet with an essential component of a getter material known per se, such as activated carbon, zeolite or dgL, wherein the getter body consists of a powder mixture with a proportion of up to 70% by weight of the getter material, e, wa 10% aluminum stearate as well as a residue containing plastic, according to patent 30 08 290, characterized that the remainder contains a portion of potassium-sodium-silicate in addition to plastic 2. Getter body according to claim I, characterized in that the plastic and potassium-sodium-silicate containing remainder is between 20 and 80 wt .-% of the getter material 3. Getter body according to claim 1 or 2, characterized in that the remainder is 10% by weight of potassium-sodium-silicate and 90% by weight of polyamide 4. A method for producing a getter body according to claim 1, characterized in that the Getter substance in powder form in water glass (potassium-sodium-silicate solution) to form a first Mixture is introduced that this first mixture is dried and ground again to powder that the powder of the first mixture with polyamide powder and aluminum stearate to form a second mixture is mixed and that finally the tablets from this second mixture be pressed. 5. The method according to claim 4, characterized in that the second mixture is dried ^{with heating to about 60 0 C before pressing.} 6. The method according to claim 4 or 5, characterized in that the pressed tablets are cured ^{at temperatures of preferably 200 0 C.} 7. The method according to any one of claims 4 to 6. characterized in that the finished tablets are deburred in a drum.