Patent ID: 11891331
Assignee: CORNING INCORPORATED
Field: Other special machines (Mechanical engineering)
Classification: CPC C | IPC C

Claim 7:
8. A method of doping a glass article with nitrogen, comprising:
supplying a nitridizing gas to a glass article through an outlet of a gas supply conduit, wherein the nitridizing gas comprises gaseous NH3, and wherein a distance between the outlet and the glass article is less than or equal to about 10 cm;
heating the glass article in a furnace to a first temperature in the presence of the nitridizing gas to form a nitrogen-doped glass article, and
wherein a residence time of the nitridizing gas is <3.0 seconds, and wherein the residence time is defined by formula (III):

Vt/f  (III)

where Vt is an interior volume of the gas supply conduit between a position at which a temperature of the nitridizing gas is >500° C. and the outlet, and where f is the volumetric flow rate of the nitridizing gas in the gas supply conduit.