| 摘要 |
<p>PURPOSE:To strengthen a glass ribbon by coating one side of the ribbon of a specified temp. with a K cpd.; supplying a DC current to ion exchange Na<+> in a ribbon surface layer for K<+>; and similarly treating the other side to increase compressive strain layers. CONSTITUTION:Molten glass drawn out of a glass melting furnace is formed into a ribbon shape on float bath 1, and glass ribbon 4 is fed into slow cooling furnace 2. When the ribbon temp. becomes 350-700 deg.C, both sides of ribbon 4 are coated with a K cpd. in the form of soln., powder or melt by means of a pair of rolls 7, 8, forming liquid or wel layers. By supplying a DC current from roll 7 to roll 9 Na<+> of the upper side is ion exchanged for K<+>. Next, the K cpd. is similarly coated by means of rolls 10, 11, and a DC current is supplied from roll 11 to roll 10 to ion exchange Na<+> of the lower side for K<+>. The both-side strengthened plate is then passed through a washing process to wash away the K cpd. and sent to a cutting process.</p> |
