Production of glass or glass-ceramic plates used as cooking surfaces comprises subjecting the plates to specified microwave radiation so that surface regions prone to breakage are subjected to lower temperature than remaining surface region

摘要

Production of glass or glass-ceramic plates with higher thermal resistance comprises subjecting glass or glass-ceramic plates to microwave radiation at a strength of 2.5-75 kW/m<2> in such a way that the surface regions prone to breakage are subjected to a lower temperature than the remaining surface region. Preferred Features: The microwave radiation has a frequency of at least 0.8 GHz. The microwave radiation last for less than 5 hours.