| 摘要 |
PURPOSE:To obtain tempered glass having high surface smoothness by heating surface-polished glass under specified conditions, carrying out ion exchange treatment, and forming a metallic film on the ion exchanged surface. CONSTITUTION:Glass is mirror-finished by polishing so that flaws remaining on the surface are reduced to <=10mu in size, and it is heated to a temp. (400-470 deg.C) below the softening point at 10-100 deg.C/sec heating rate and heat treated at the temp. for a fixed time. This glass is then dipped in KNO3 molten salt or KNO3- AgNO3 molten salt of a predetermined temp. to carry out ion exchange treatment, and a metallic layer of Cr, Al, Cu, MgF2 or the like is formed on the ion exchanged glass surface by vapor deposition, sputtering, spraying or other method. Thus, the flaws on the glass surface are diminished, the reflectance of the glass and the adhesion of the metallic film are enhanced, and the occurrence of thermal impact breaking can be decreased. |
