METHOD FOR IONEXCHANGE COLOURING OF GLASS GOODS

摘要

The method is applied for colouring household glassware. It reduces the expenditure of silver and retains the intensity of colouring. Additionally, it enhances the mechanical strength of glassware. After preliminary cleaning and drying, the glassware is treated in a bath with melt, containing a mixture of 1 to 5 mol% silver nitrate and 90-95 mol% kalium nitrate under temperature of 350 to 380 degrees C with a time of process of 5 to 15 minutes. After this, the glassware is transfered in another bath with melt, containing 40-50 mol.% kalium nitrate and 40-50 mol.% sodium nitrate and are secondarily treated under temperature of 450 to 550 degrees C for 20 minutes to 2 hours. There follows a cooling to a room temperature. Depending on the selected regime of the secondary thermal treatment, the glassware is coloured in a light yellow to intensely brown colour.