EP0349909A1
Expired / Lapsed
EP
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Dark, neutral gray, nickel-free glass composition
Assignee: PPG Industries Inc
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Filing: 1989-06-30
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Granted: —
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Expires: 2009-06-30
Abstract
Abstract A neutral, dark gray, nickel-free, soda-lime-silica glass having luminous transmittance less than 20 percent is produced with colorants consisting essentially of 0.55 to 1.0 percent by weight total iron (at least 15 percent in the ferrous state), 0.005 to 0.02 percent CoO, and 0.003 to 0.02 percent Se. The flat glass product having such a composition is particularly suitable for use in sun roofs.
Inventors
- 👤 James Victor Jones
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 02:25
CPC Classifications
C; C03; C03C; C03C4/00; C03C4/02; C03C1/00; C03C1/10; C03C3/00; C03C3/04; C03C3/076; C03C3/078; C03C3/083; C03C3/085; C03C3/087
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
102 words
A neutral gray colored glass composition having a base glass composition comprising: SiO₂ 68 - 75 percent by weight Na₂O 10 - 18 CaO 5 - 15 MgO 0 - 5 Al₂O₃ 0 - 5 K₂O 0 - 5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe₂O₃ (total iron) 0.55 - 1.0 percent by weight Se 0.003 - 0.02 CoO 0.005 - 0.02 at least 15 percent of the iron being in the ferrous state, the glass having a luminous transmittance of no more than 20 percent at a thickness of 5.56 millimeters (0.219 inch).
Claim 2
Dependent Claim
102 words
A neutral gray colored glass composition having a base glass composition comprising: SiO₂ 68 - 75 percent by weight Na₂O 10 - 18 CaO 5 - 15 MgO 0 - 5 Al₂O₃ 0 - 5 K₂O 0 - 5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe₂O₃ (total iron) 0.55 - 1.0 percent by weight Se 0.003 - 0.02 CoO 0.005 - 0.02 at least 15 percent of the iron being in the ferrous state, the glass having a luminous transmittance of no more than 20 percent at a thickness of 5.56 millimeters (0.219 inch).
Claim 3
Dependent Claim
30 words
The composition of claim 1 wherein the portion of the iron in the ferrous state constitutes 0.09 to 0.3 percent by weight of the total glass composition, expressed as FeO.
Claim 4
Dependent Claim
29 words
The composition of claim 1 wherein the colorant portion consists essentially of: Fe₂O₃ (total iron) 0.6 - 0.8 percent by weight Se 0.005 - 0.01 CoO 0.01 - 0.02
Claim 5
Dependent Claim
33 words
The composition of claim 3 wherein the portion of the iron in the colorants in the ferrous state constitutes 0.10 to 0.2 percent by weight of the total glass composition, expressed as FeO.
Claim 6
Dependent Claim
99 words
A glass sheet having a base glass composition comprising: SiO₂ 68 - 75 percent by weight Na₂O 10 - 18 CaO 5 - 15 MgO 0 - 5 Al₂O₃ 0 - 5 K₂O 0 - 5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe₂O₃ (total iron) 0.55 - 1.0 percent by weight Se 0.003 - 0.02 CoO 0.005 - 0.02 at least 15 percent of the iron being in the ferrous state, the glass having a luminous transmittance of no more than 20 percent at a thickness of 5.56 millimeters (0.219 inch).
Claim 7
Dependent Claim
99 words
A glass sheet having a base glass composition comprising: SiO₂ 68 - 75 percent by weight Na₂O 10 - 18 CaO 5 - 15 MgO 0 - 5 Al₂O₃ 0 - 5 K₂O 0 - 5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe₂O₃ (total iron) 0.55 - 1.0 percent by weight Se 0.003 - 0.02 CoO 0.005 - 0.02 at least 15 percent of the iron being in the ferrous state, the glass having a luminous transmittance of no more than 20 percent at a thickness of 5.56 millimeters (0.219 inch).
Claim 8
Dependent Claim
17 words
The glass sheet of claim 5 wherein the sheet has a thickness of 2 to 10 millimeters.
Claim 9
Dependent Claim
17 words
The glass sheet of claim 5 wherein the sheet has a thickness of 3 to 6 millimeters.
Claim 10
Dependent Claim
21 words
The glass sheet of claim 5 wherein a surface portion of the sheet includes at least 0.05 percent by weight SnO₂.
Claim 11
Dependent Claim
32 words
The glass sheet of claim 5 wherein the portion of the iron in the colorants in the ferrous state constitutes 0.09 to 0.3 percent by weight of the glass, expressed as FeO.
Claim 12
Dependent Claim
37 words
The glass sheet of claim 5 wherein the colorant portion of the composition of the glass sheet consists essentially of: Fe₂O₃ (total iron) 0.6 - 0.8 percent by weight Se 0.005 - 0.01 CoO 0.01 - 0.02
Claim 13
Dependent Claim
32 words
The glass sheet of claim 10 wherein the portion of the iron in the colorants in the ferrous state constitutes 0.10 to 0.2 percent by weight of the glass, expressed as FeO.
Claim 14
Dependent Claim
23 words
The glass sheet of claim 5 wherein the luminous transmittance is less than 15 percent at a thickness of 5.56 millimeters (0.219 inch).
Claim 15
Dependent Claim
21 words
The glass sheet of claim 5 wherein a reflective coating on at least one surface of the glass sheet is present.
References Cited (Backward Citations)
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