INCLUDING SMALL AESTHETIC BUBBLES IN GLASS ARTICLES
A method of forming glass articles involves introducing a particulate mixture ( 20 ) of SiC particles and carrier particles into molten glass ( 44, 22 ) contained within at least one of a forehearth ( 12 ) or a fining chamber ( 28 ) of a glass-making furnace ( 10 ). The particulate mixture ( 20 ) creates seeds (S) within the molten glass such that an outflow of conditioned molten glass ( 18 ) discharged from the forehearth ( 12 ) and the glass articles produced therefrom contain a greater concentration of seeds (S) than if the particulate mixture ( 20 ) is not added. The concentration of seeds (S) in the glass articles can be controlled by commencing or withholding the addition of the particulate mixture ( 20 ).
1 . A method of forming glass articles, the method comprising:
providing a glass-making furnace that comprises a melting chamber, a fining chamber, and a forehearth, the melting chamber and the fining chamber being separated by a throat, and the forehearth being fluidly coupled to the fining chamber, and wherein the melting chamber contains a molten glass bath into which a vitrifiable feed material is introduced, the fining chamber contains a molten glass fining bath that receives glass from the molten glass bath in the melting chamber through the throat, and the forehearth that includes an elongated channel along which a flow of molten glass pulled from the molten glass fining bath travels;
introducing a particulate mixture that comprises SiC particles and carrier particles into at least one of the molten glass fining bath or the flow of molten glass within the forehearth to create seeds within, and to thereby increase a concentration of seeds within, the flow of molten glass within the forehearth;
discharging an outflow of conditioned molten glass from the forehearth; and
forming a glass article from the outflow of conditioned molten glass.
2 . The method set forth in claim 1 , wherein the carrier particles included in the particulate mixture comprise cullet particles.
3 . The method set forth in claim 1 , wherein the carrier particles included in the particulate mixture comprise glass frit.
4 . The method set forth in claim 1 , wherein the carrier particles included in the particulate mixture comprise vitrifiable particles that melt into a vitreous state when introduced into the flow of molten glass.
5 . The method set forth in claim 1 , wherein the SiC particles in the particulate mixture have particle sizes that range from 10 μm to 120 μm, and wherein the carrier particles in the particulate mixture have particle sizes that range from 50 μm to 300 μm.
6 . The method set forth in claim 5 , wherein the SiC particles in the particulate mixture have particle sizes that range from 30 μm to 80 μm, and wherein the carrier particles in the particulate mixture have particle sizes that range from 100 μm to 200 μm.
7 . The method set forth in claim 1 , wherein a weight ratio of the SiC particles to the carrier particles in the particulate mixture ranges from 1:1000 to 1:2.5.
8 . The method set forth in claim 7 , wherein the weight ratio of the SiC particles to the carrier particles in the particulate mixture ranges from 1:500 to 1:100.
9 . The method set forth in claim 7 , wherein the weight ratio of the SiC particles to the carrier particles in the particulate mixture ranges from 1:500 to 1:250.
10 . The method set forth in claim 1 , wherein a flow rate of a combined weight of the SiC particles and the carrier particles in the particulate mixture into at least one of the molten glass fining bath or the flow of molten glass within the forehearth ranges from 0.1% to 5.0% of a discharge flow rate of the outflow of conditioned molten glass from the forehearth.
11 . The method set forth in claim 10 , wherein the flow rate of the combined weight of the SiC particles and the carrier particles ranges from 0.5% to 0.75% of the discharge flow rate of the outflow of conditioned molten glass from the forehearth.
12 . The method set forth in claim 1 , wherein the particulate mixture is introduced into the flow of molten glass within in a zone of the forehearth in which a temperature of the flow of molten glass ranges from 1100° C. to 1400° C.
13 . The method set forth in claim 1 , wherein the SiC particles and the carrier particles in the particulate mixture have particle sizes that range from 10 μm to 120 μm and from 50 μm to 300 μm, respectively, wherein a weight ratio of the SiC particles to the carrier particles in the particulate mixture ranges from 1:1000 to 1:2.5, wherein the particulate mixture is introduced into the flow of molten glass within in a zone of the forehearth in which a temperature of the flow of molten glass ranges from 1100° C. to 1400° C., and wherein a flow rate of a combined weight of the SiC particles and the carrier particles in the particulate mixture into the flow of molten glass within the forehearth ranges from 0.1% to 5.0% of a discharge flow rate of the outflow of conditioned molten glass from the forehearth.
14 . The method set forth in claim 1 , wherein the outflow of conditioned molten glass has a soda-lime-silica glass chemical composition.
15 . The method set forth in claim 1 , wherein forming the glass article from the outflow of conditioned molten glass comprises forming a glass container that includes a hollow glass substrate.
16 . A method of forming glass articles, the method comprising:
(a) delivering a flow of molten glass into an elongated channel of a forehearth along which the flow of molten glass is cooled;
(b) discharging an outflow of conditioned molten glass from the forehearth as a first set of gobs of molten glass, the outflow of conditioned molten glass having a first concentration of seeds;
(c) forming a glass article from one of the gobs of the first set of gobs of molten glass;
(d) introducing a particulate mixture that comprises SiC particles and carrier particles into at least one of the flow of molten glass that is flowing through the forehearth or a molten glass fining bath from which the flow of molten glass within the forehearth is pulled, the particulate mixture increasing a concentration of seeds within the outflow of conditioned molten glass from the first concentration of seeds to a second concentration of seeds, wherein the carrier particles comprise at least one of cullet particles, glass frit particles, or vitrifiable particles;
(e) discharging the outflow of conditioned molten glass from the forehearth as a second set of second individual gobs of molten glass after introducing the particulate mixture in step (d); and
(f) forming a glass article from one of the gobs of the second set of individual gobs of molten glass.
17 . The method set forth in claim 16 , wherein the outflow of conditioned molten glass has a soda-lime-silica glass chemical composition.
18 . The method set forth in claim 16 , wherein each of the glass article formed in step (c) and the glass article formed in step (f) is a glass container that includes a hollow glass substrate having an closed base and a peripheral wall that extends from the closed base to a mouth.
19 . The method set forth in claim 16 , wherein the glass article formed in step (f) has a seed concentration that ranges from 4 seeds per gram of glass to 10 seeds per gram of glass.