| 摘要 |
PURPOSE:To provide a molding method in high yield for the subject glass form of high quality, free from cracks and residual bubbles. CONSTITUTION:In molding a porous glass form 40 by CIP means, a cylindrical mold 11 for molding is externally pressurized in such a state that at least one end of a molding bar 38 is projected out of the molding space 42. At least one edge face of the molding space 42 is left to be swollen inwardly. Thereby, the deflection of the bar 38 in molding a porous glass form 40 and the cracking of the form 40 in the subsequent removal of the bar 38 and insertion of an optical waveguide bar 44 can be suppressed to fairly low levels, leading to improving the yield of the molded product. On swelling the edge face(s) of the molding space in specified direction, the packing density of a molding material in the space 42 gets uniform and sufficiently deaerated, thus obtaining the objective molded product of higher quality. |
