CHEMICAL STRENGTHENING TREATMENT UNIT FOR APPLYING CHEMICAL STRENGTHENING TREATMENT TO GLASS SUBSTRATES USED IN INFORMATION RECORDING MEDIA APPLICATIONS

摘要

A UNIT FOR APPLYING CHEMICAL STRENGTHENING TREATMENT TO GLASS SUBSTRATES FOR INFORMATION RECORDING MEDIA APPLICATIONS. THE UNIT COMPRISES A HOLDER FOR HOLDING A PLURALITY OF GLASS SUBSTRATE AND A TANK WHICH CONTAINS A MOLTEN SOLUTION OF A PRESCRIBED SALT. IN THE UNIT, THE GLASS SUBSTRATE IS CHEMICALLY STRENGTHENED BY REPLACING A PART OF THE IONS IN THE GLASS SUBSTRATES WITH THE IONS IN SAID MOLTEN SOLUTION AND HAVING ION RADIUS LARGER THAN THAT OF THE IONS IN THE GLASS SUBSTRATE. AT LEAST ONE OF THE HOLDER AND THE TANK IS FORMED OF A NICKEL ALLOY.