Abstract: Quartz solid solution glass ceramics and precursors thereof are described, which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

Abstract: Ceramics and glass-ceramics have low and/or negative coefficients of thermal expansion. Crystalline phases of the formula AM2Si2-yGeyO7 (A=Sr and Ba and M=Zn, Mg, Ni, Co, Fe, Cu, Mn, with Sr, Ba and Zn necessarily having to be present) can be produced by conventional ceramic processes or by crystallization from glasses. The compositions form solid solutions, where the elements indicated as component M can be replaced by one another in virtually any concentration but the concentration of Zn must always be at least 50% of the sum of all components indicated under M. The stoichiometry of these silicates and also their structure can differ to a greater or lesser extent.

Abstract: Quartz solid solution glass ceramics and precursors thereof are described, which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

Abstract: A glass composition, a device and a method for producing the device are disclosed. In an embodiment, the glass composition includes a tellurium oxide in a proportion of at least 65 mol. % and at most 90 mol. %, R1O in a proportion between 0 mol. % and 20 mol. %, wherein R1 is selected from Mg, Ca, Sr, Ba, Zn, Mn and combinations thereof and at least one M12O in a proportion between 5 mol. % and 25 mol. %, wherein M1 is selected from Li, Na, K and combinations thereof. The glass component further includes at least one R22O3 in a proportion between 1 mol. % and 3 mol. %, wherein R2 is selected from Al, Ga, In, Bi, Sc, Y, La, rare earths and combinations thereof, and M2O2 in a proportion between 0 mol. % and 2 mol. %, wherein M2 is selected from Ti, Zr, Hf and combinations thereof.

Abstract: Ceramics and glass-ceramics have low and/or negative coefficients of thermal expansion. Crystalline phases of the formula AM2Si2-yGeyO7 (A=Sr and Ba and M=Zn, Mg, Ni, Co, Fe, Cu, Mn, with Sr, Ba and Zn necessarily having to be present) can be produced by conventional ceramic processes or by crystallization from glasses. The compositions form solid solutions, where the elements indicated as component M can be replaced by one another in virtually any concentration but the concentration of Zn must always be at least 50% of the sum of all components indicated under M. The stoichiometry of these silicates and also their structure can differ to a greater or lesser extent.

Abstract: Quartz solid solution glass ceramics and precursors thereof are described, which are characterized by very good mechanical and optical properties and in particular can be used as restoration material in dentistry.

Abstract: A glass composition, a device and a method for producing the device are disclosed. In an embodiment, the glass composition includes a tellurium oxide in a proportion of at least 65 mol. % and at most 90 mol. %, R1O in a proportion between 0 mol. % and 20 mol. %, wherein R1 is selected from Mg, Ca, Sr, Ba, Zn, Mn and combinations thereof and at least one M12O in a proportion between 5 mol. % and 25 mol. %, wherein M1 is selected from Li, Na, K and combinations thereof. The glass component further includes at least one R22O3 in a proportion between 1 mol. % and 3 mol. %, wherein R2 is selected from Al, Ga, In, Bi, Sc, Y, La, rare earths and combinations thereof, and M2O2 in a proportion between 0 mol. % and 2 mol. %, wherein M2 is selected from Ti, Zr, Hf and combinations thereof.

Abstract: The invention is directed to an aluminoborosilicate glass containing alkali metals for the production of optical components with refractive index gradients which are generated by ion exchange of monovalent metal ions in a base glass comprising at least silicon oxide, boron oxide, aluminum oxide and an alkali metal oxide, particularly for the production of gradient index lenses (GRIN lenses).

Abstract: The invention is directed to an aluminoborosilicate glass containing alkali metals for the production of optical components with refractive index gradients which are generated by ion exchange of monovalent metal ions in a base glass comprising at least silicon oxide, boron oxide, aluminum oxide and an alkali metal oxide, particularly for the production of gradient index lenses (GRIN lenses).