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

摘要

A method for producing a glass substrate for information recording media applications, the method including: providing the glass substrate having a peripheral surface and a recording surface; polishing the peripheral surface of the glass substrate; lapping polishing the recording surface; precision polishing the recording surface; supporting the glass substrate in a holder; and performing a chemical strengthening treatment for forming a compressive stress layer on the glass substrate by immersing the glass substrate into a molten solution of a prescribed salt, wherein said molten solution is contained within a tank, and wherein at least one of the holder and the tank includes a nickel alloy that contains nickel as a major constituent.