US 12,291,475 B2
Method for forming molten glass, forming apparatus, and method for producing glass product
Motoichi Iga, Chiyoda-ku (JP); Toru Kamihori, Chiyoda-ku (JP); and Masanori Nakano, Chiyoda-ku (JP)
Assigned to AGC Inc., Chiyoda-ku (JP)
Filed by AGC Inc., Chiyoda-ku (JP)
Filed on Aug. 1, 2019, as Appl. No. 16/529,306.
Application 16/529,306 is a continuation of application No. PCT/JP2018/005120, filed on Feb. 14, 2018.
Claims priority of application No. 2017-026061 (JP), filed on Feb. 15, 2017.
Prior Publication US 2019/0352209 A1, Nov. 21, 2019
Int. Cl. C03B 17/06 (2006.01); C03B 18/12 (2006.01); C03B 18/18 (2006.01); C03B 25/093 (2006.01)
CPC C03B 17/06 (2013.01) [C03B 18/12 (2013.01); C03B 18/18 (2013.01); C03B 25/093 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for forming molten glass, comprising:
adjusting a temperature of a portion of molten metal where a glass ribbon makes first contact with the molten metal such that a temperature of the portion of the molten metal is brought to be lower than a softening point of the molten glass and higher than an annealing point of the molten glass;
setting a temperature of the molten glass in a supply device having a discharge section that discharges the molten glass in a strip shape and supplies the molten glass in a form of the glass ribbon such that a viscosity n of the molten glass become within a range of 1.5≤log η≤5 where η is in dPa·s;
discharging the molten glass in the strip shape on a surface of the molten metal such that the molten glass is supplied in the form of the glass ribbon on a surface of the portion of the molten metal where the temperature is kept lower than the softening point of the molten glass and higher than the annealing point of the molten glass; and
transporting the glass ribbon comprising the molten glass and supplied on the surface of the portion of the molten metal from an upstream side to a downstream side in a transport direction such that a thickness of the glass ribbon is maintained on the surface of the molten metal during the transporting,
wherein the discharging comprises dropping the molten glass having a temperature of at least the softening point in the form of the glass ribbon vertically downward such that during the dropping, the glass ribbon is cooled by a cooling device configured to cool the glass ribbon, has a temperature of at least the softening point of the molten glass and is stretched by an own weight of the glass ribbon and adjusted to the thickness for the transporting, and said transporting includes cooling the glass ribbon being transported on the molten metal in a region on the upstream side in the transport direction such that the temperature of the glass ribbon becomes lower than the softening point of the molten glass in an entire width direction.