| 摘要 |
Provided is a method for strengthening a substrate by a first exchange medium and a second exchange medium, the substrate including a treatment-rich volume and a treatment-poor volume, the method containing (a) treating a surface of the treatment-poor volume of the substrate and (b) treating a surface of the treatment-rich volume of the substrate, in which the treating step (a) contains putting the surface of the treatment-poor volume in contact with a first exchange medium and optionally with a second exchange medium and processing the surface of the treatment-poor volume for total period of time T1, and the treating step (b) contains putting the surface of the treatment-rich volume in contact with the second exchange medium and processing the surface of the treatment-rich volume for period of time T2, in which T1>T2. |
