| 摘要 |
PROBLEM TO BE SOLVED: To produce a glass gob suitable for the press-molding of an optical device and free from unevenness on the surface. SOLUTION: A mold for producing a glass gob 8 used for the optical device has a gob mold 1 comprising a porous material to receive a molten glass lump 7 and the molten glass lump 7 is floated by blowing a gas from the surface 2 of the gob mold 1 to cool and solidify the glass lump. The porous material comprising the gob mold 1 is aggregate of particles which has >25% and <40% porosity (volume ratio), wherein the ratio (the number of particles) of particles having 30-300μm particle diameter occupies≥80% of the whole. The occurrence of the unevenness due to the contact with the surface 2 is prevented by using the porous material and stably floating the molten glass lump 7 by the gas blown from the surface 2. COPYRIGHT: (C)2010,JPO&INPIT |
