DE1003005B - Process for the production of thin, flexible glass coatings on wires, foils and similar carriers - Google Patents

Description

GERMAN

The organic insulation coatings that have been widely used up to now for wires, foils and similar substrates generally do not allow operating temperatures higher than 80 to 100 ° C. An increase these operating temperatures is possible by using thin, flexible glass coatings, their thickness is preferably only 10 μ or less.

However, it is generally necessary to produce glass coatings that are inherently dense and further are as uniform (homogeneous) as possible. One can think of it, the finished glass mass from one accordingly to evaporate heated vessel. This is not easily possible with all types of glass, i. H. not with those types of glass in which the partial vapor pressures of the components are too far apart and in which thus fractional distillation can occur.

It has also been proposed to coat a glass on a support by electrophoresis of small To generate glass particles or glass components. This assumes that initially very small glass particles or glass components for forming glass by grinding or a similar crushing process and these are then applied to the support by electrophoresis. It is in the The nature of this process is that the resulting coating is not inherently impermeable and in terms of its quality of the Smallness of the glass particles or glass components used is dependent. But since this is not arbitrary small and also not of uniform shape and size can be produced, so is the resulting one Coating irregular and porous. One is therefore compelled to im. Following the electrophoretic application of the coating to heat the carrier with the coating high in order to through the associated Melting or sintering process to form the glass coating from the glass components and the so formed or to make the glass coating applied directly by electrophoresis as tight as possible. This can be can only be achieved imperfectly, and the thickness of the glass coating cannot fall below a certain level.

The invention provides a method that suffers from the aforementioned difficulties and limitations free is. The new solution is that on the one hand the glass mass of the thin one to be formed Coating formed on the carrier itself and that this, on the other hand, the components of the to be formed Glass mass can be applied in whole or in part by vapor deposition in a high vacuum. This allows achieve that you have a glass coating in the desired thickness and composition with large Achieved uniformity. You can get the individual components from separate evaporation boats

Process for producing thin, flexible glass coatings on wires,

Foils and similar carriers

Applicant:

Siemens-Schuckertwerke

Corporation,

Berlin and Erlangen,

Erlangen, Werner-von-Siemens-Str. 50

Dr. Walter Hänlein, Erlangen,
has been named as the inventor

vaporize, which are heated according to the nature of the individual components., so so that the different boats may have different heating temperatures. How else it is known in various fields to apply a coating, e.g. B. made of metal, in a high vacuum to evaporate. In contrast, however, it is new to produce a glass coating in the aforementioned manner.

In one embodiment, all of the components required for the subsequent glass coating are used vapor-deposited onto the carrier. But it is also possible to use some of the components for the Later glass coating required glass mass to add the substance from which the carrier is formed or to be taken from this material.

One can also proceed so that on the carrier a substance that forms glass acid is vaporized and then the vapor-deposited material through an oxidation process is transferred into a thin glass coating. This procedure can also be modified so that that on the first coating alkali oxides and / or alkaline earth oxides are vaporized and then the coatings thus formed are subjected to an oxidation process to form the glass layer.

The method can e.g. B. be carried out in the following manner. It is first applied to the carrier Substance, the glass acid, d. H. acidic oxides, like silicon, boron or phosphorus, form in glass in a high vacuum vaporized. Then the vapor-deposited substance is through an oxidation process, for. B. by

609- 836/261

heat in an oxygen-containing atmosphere, in a thin Glass coating transferred. This glass coating can, for. B. from vitreous silica and / or vitreous Boric acid. . .

A modification of the procedure described last consists in the fact that on the carrier again a substance that forms glass acid, such as silicon or boron, vaporized and then by a temperature treatment (preferably heating in oxygen-containing Atmosphere) the coating produced is converted into a glassy metal silicate or metal borate. In this case, if the carrier is made of copper or contains copper, a coating is obtained made of copper silicate or copper borate or copper phosphate.

Another embodiment of the method consists in that first a substance, the glass acid forms, such as silicon, boron or phosphorus, is evaporated and simultaneously or subsequently Alkali oxides or alkaline earth oxides are vaporized and that then the coatings be subjected to an oxidation process (heating in an oxygen-containing atmosphere), in the sense of Transfer of the vapor-deposited layers or vapor-deposited components into the desired glass layer.

The individual substances or components can be extracted from common or separate evaporation vessels be vaporized.

It is also possible to add additives to the substances used for the manufacture of the carrier, the glass acid form, so z. B. silicon, boron or phosphorus, to add or to use for the carrier those that the contain the aforementioned glass acid-forming substances. The components that are still required for the later Glass coating, such as alkali oxides and / or alkaline earth oxides, are then evaporated onto the carrier. Then the carrier with its coating is subjected to an oxidation process in the sense the transfer of the aforementioned components into a glassy state.

As already indicated, the various operations can be carried out one after the other, there but it is also possible to use the individual procedures to carry out separately listed operations at the same time or to allow them to overlap in time.

The new method is relatively simple to carry out and is particularly suitable for a good insulation coating on wires, as required for electrotechnical purposes, or on metal foils, as they are, for. B. for the production of "of" electrical capacitors are used to generate. The new procedure is generally applicable irrespective of the purposes for which the wires, foils and similar carriers are intended to serve.

When the glass coating produced is said to be pliable is, it is intended to express that the carrier is more or less flexible should be without the glass coating cracking or peeling off.

Claims (6)

Patent claims: 1. Process for the production of thin, flexible glass coatings on wires, foils and Similar carriers, characterized in that on the one hand the glass mass of the thin to be formed Coating formed on the carrier itself and that this, on the other hand, the components of the to be formed Glass mass can be applied in whole or in part by vapor deposition in a high vacuum. 2. The method according to claim 1, characterized in that some of the components of the for the subsequent glass coating required glass mass is the substance from which the carrier is formed is added to or removed from it. 3. The method according to claim 1, characterized in that first a substance on the carrier, The glass acid forms, like silicon or boron, and then the vapor-deposited substance by an oxidation process into a thin glass coating, e.g. B. from vitreous silica and / or vitreous boric acid. 4. The method according to claim 3, characterized in that by a temperature treatment the coating in a glassy metal silicate or metal borate, e.g. B. for copper-containing carriers in a coating of copper silicate or copper borate. 5. The method according to claim 1, characterized in that on the carrier first a substance, The glass acid forms, such as silicon, boron or phosphorus, evaporated and then alkali oxides and / or alkaline earth oxides are evaporated and that the coatings are then subjected to an oxidation process, in the sense of the transfer of the applied layers into a glass layer. 6. The method according to claim 2, characterized in that the for the production of the carrier Substance used Additives that form glassic acid, such as silicon, boron or phosphorus, are added and that the components that are still required for the subsequent glass coating, such as alkali oxides and / or Erdälkalioxyde, evaporated onto the carrier and that then the carrier with its coating is subjected to an oxidation process becomes, in terms of the transformation of the components in a glassy state. Documents considered: German Patent Specifications No. 666 930, 816 934; U.S. Patent No. 2,533,351. 0 609 856/261 2.57