| 摘要 |
PURPOSE:To obtain the title parent material of stabilized quality without cracking or the like, by jetting a gas from a specific nozzle set on the end opposing to the soot-depositing face at the initial stage of particle glass deposition to prevent deposition of glass particles of low bulk density in the production of the title parent materials by the soot formation method. CONSTITUTION:In the reaction vessel 1 of the unit for making the title parent material by the soot formation process, the starting rod 2 is set and glass particles are formed by feeding the feedstock gas for glass such as SiCl4, SiHCl3 or the like, and, when needed, GeCl4 as a dopant into the flame 5 formed by jetting combustion gas such as hydrogen or methane as wells as a combustion- supporting oxygen gas from the burner 2 whereby the soot is deposited on the bottom end of the rod 2 to form the parent material. At the initial stage of soot deposition until the outer diameter of the parent material reaches a certain value, a gas is blown from the nozzle 7 which can traverse by a mechanism 10 set near the opposite end of the soot deposition face to prevent the excess deposition of soot hear the top end 8. |
