摘要 |
IN A METHOD OF MANUFACTURING A GLASS SUBSTRATE FOR AN INFORMATION RECORDING MEDIUM INCLUDING A STEP FOR CHEMICALLY STRENGTHENING THE GLASS SUBSTRATE BY CONTACTING THE GLASS SUBSTRATE WITH CHEMICAL STRENGTHENING PROCESSING LIQUID CONTAINING CHEMICAL STRENGTHENING SALT, CONCENTRATION OF FE AND CR IS 500 PPB OR LESS IN SAID CHEMICAL STRENGTHENING SALT, RESPECTIVELY. THE CONCENTRATION MAY BE DETECTED BY THE USE OF AN ICP (INDUCTIVELY COUPLED PLASMA) EMISSION SPECTROMETRY ANALYZING METHOD OR A FLUORESCENT X-RAY SPECTROSCOPY ANALYZING METHOD. |