Method for manufacturing glass-fine-particle-deposited body and method for manufacturing glass base material

摘要

In the method for manufacturing a glass-fine-particle-deposited body according to the present invention, at least a part of a gas supplying pipe 25 from a temperature controlled booth 24 to a burner 18 for cladding is temperature-controlled so that the temperature at the burner side becomes high and temperature gradient becomes 5° C./m or more. The temperature control is performed so that the temperature gradient becomes preferably 15° C./m or more, more preferably 25° C./m or more. Specifically, the part is controlled to the predetermined temperature gradient by winding a tape heater 26 that is a heating element on the outer circumference of the gas supplying pipe 25 from the temperature controlled booth 24 to the burner 18 for cladding and temperature-controlling the tape heater 26.

主权项

1. A method for manufacturing a glass-fine-particle-deposited body, the method comprising:
heating and vaporizing a liquid glass source material placed in a source material container to form one glass source material gas; introducing the glass source material gas to a burner for producing glass-fine-particles from the source material container through a pipe having an inner diameter not less than 2.7 mm and not more than 19 mm, a Reynolds number of the glass source material gas flowing in the pipe from the source material container to the burner controlled to 2,000 or more; spouting the glass source material gas from the burner for producing glass-fine-particles; and depositing glass fine particles produced by a flame decomposition reaction of the glass source material gas on a starting rod in a reaction container to prepare a glass-fine-particle-deposited body, during the depositing step, a region of one third or less of a longitudinal direction from an end part at a pipe side in the burner for producing glass-fine-particles is controlled to a temperature of 200° C. or higher by the heating element, wherein at least a part of the pipe from the source material container to the burner for producing glass-fine-particles in the deposition step is temperature-controlled by a heating element to a temperature of 200° C. or higher and so that a burner side has a higher temperature than a source material container side and temperature gradient of said at least part of the pipe becomes 5° C./m or more, and a plurality of pipes along a central axis of the burner for producing glass-fine-particles are formed in the burner for producing glass-fine-particles, and the glass source material gas is supplied into one of the plurality of pipes which is provided at an innermost side of the central axis.