Schott Ag

Thoralf Johansson

Falk Gabel

Michael Bug

Otmar Becker

Dietmar Wennemann

Harald Striegler

Gerhard Hahn

Helga Goetz

Friedrich-Georg Schroeder

Veit Luther

Petra Grewer

Jan-Peter Ortmann

Guenther Siebenhaar

Michael Glasenapp

Thomas Schuler

Friedrich Siebers

Evelin Weiss

Ralf Jedamzik

Clemens Kunisch

Uwe Martens

Christian Roos

Friedrich Georg Schroder

Friedrich Georg SCHRÖDER

Helga GÖTZ

Günther Siebenhaar

Friedrich-Georg SCHRÖDER

An LAS-glass for producing a transparent glass-ceramic and an LAS-glass-ceramic having a predetermined chroma C* and a predetermined visually determinable scatter value (S) are provided. The LAS-glass and LAS-glass-ceramic has a process window as large as possible during the nucleus formation process with respect to the residence time in the relevant temperature range for the formation of nuclei.

Glass and glass ceramic

The invention generally relates to manufacturing or providing of glass or glass ceramic products. The invention is based on the object to allow for providing glass or glass ceramic products having very accurately characterized thermo-mechanical properties. For this purpose, a deformation of the glass or glass ceramic material is measured at least twice as a function of time with different rates of change in temperature or a mechanical stress. Based on the measurements, relaxation times and weighting factors are determined by modelling. Then, based on the relaxation times and weighting factors related to the distribution of relaxation processes occurring in the product, a time-delayed change of a temperature-dependent or stress-dependent physical quantity, such as thermal expansion or refractive index, is calculated as a function of a predefined temperature change or stress change. The invention is used for selecting during manufacturing suitable glass products exhibiting selected time-delayed properties.

Method for determining time-delayed changes of temperature-dependent or stress-dependent physical quantities of a glass or a glass ceramic

A lithium-containing, transparent glass-ceramic material is provided. The material has low thermal expansion and has an amorphous, lithium-depleted, vitreous surface zone. The zone is at least 50 nm thick on all sides and encloses a crystalline interior, which has high transmission. The material includes a transition region connecting the zone and the interior.

Transparent lithium glass-ceramic material, production and use thereof

The invention relates to a method and to a device for ceramizing green glass in a continuous furnace, with the ceramization being carried out directly on rollers.

Glass ceramic article and method and device for ceramizing glass

Growing community of inventors

Nieder-Olm, Germany

Thoralf Johansson