In order to guarantee these properties, a lot of materials have to be tested in order to develop their best properties that typify the product.

For example, the durability of glass or ceramic materials is tested in laboratory conditions using multi-stage challenge tests. In such tests, samples of these materials are repeatedly subject to physicochemical stress procedures in which they are exposed to a high degree of wear. It is therefore necessary to distinguish such material samples using a marking which does not itself change, even when samples are chemically or mechanically disrupted. This why a research team of scientists from the Department of Microelectronics, the Faculty of Electrical Engineering and Communication at Brno University of Technology have developed a marking method.

The marking method is based on the way samples made of glass or ceramics are permanently marked. Samples are marked with a code, a character or a set of characters created on the sample surface. This method uses contrastingly coloured glass paste, which is then heat-processed by firing. Such marking is then highly resistant against the intensive laboratory testing of such materials.

For this marking method a dispenser is used to apply a contrastingly coloured glass paste onto the surface of a glass or ceramic sample in the form of a specific marking code or figure. The paste is then dried and heat-processed at the temperature of the re-melting or re-crystallization of the paste. Thus a resistant marking is made, with similar physical and chemical properties as those of the basic material of the sample. During chemical, mechanical or other (e.g. ionizing irradiation) exposure of the samples, the marking remains permanently on the surface and thus allows the tested sample to be better identified. The method is protected by a patent and an utility model.