DOUBLE ION EXCHANGE PROCESS

摘要

A method for optimizing ion exchange of glass. The glass is ion exchanged in a series of two ion exchange baths. The first ion exchange bath contains an amount of a poisoning ion or salt and the second ion exchange bath contains an amount of the poisoning ion or salt that is less than that in the first bath. When the concentration of the poisoning ion/salt in the first bath reaches a maximum value, the first bath is discarded and replaced by the second bath and a third bath that initially does not contain the poisoning cation/salt replaces the second ion exchange bath. This cycling of baths may be repeated to produce a plurality of glass articles, each having a surface layer under a compressive stress and depth of layer that are within predetermined limits.

主权项

1. A method of ion exchanging a plurality of glass articles, the method comprising:
a. ion exchanging a first portion of the glass articles in a first ion exchange bath, the first ion exchange bath comprising a concentration of a poisoning cation that is less than or equal to a maximum concentration x and greater than or equal to a minimum concentration y; b. ion exchanging the first portion in a second ion exchange bath following ion exchanging the first portion in the first ion exchange bath, the second ion exchange bath comprising the poisoning cation in a concentration that is less than or equal to the minimum concentration y; c. replacing the first ion exchange bath with a first replacement ion exchange bath when the concentration of the poisoning cation in the first ion exchange bath exceeds the maximum concentration x, the first ion exchange replacement bath having a concentration of the poisoning ion that is less than the maximum concentration x and greater than or equal to the minimum concentration y; d. ion exchanging a second portion of the glass articles in the first replacement ion exchange bath; e. replacing the second ion exchange bath with a second replacement ion exchange bath when the concentration of the poisoning cation in the second ion exchange bath is greater than or equal to the minimum concentration y, the second ion exchange replacement bath having a poisoning ion concentration that is less than the minimum concentration y; and f. ion exchanging the second portion in the second replacement ion exchange bath.