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US5023210A Expired / Lapsed US ⏱️ 0.0 years remaining

Neutral gray, low transmittance, nickel-free glass

Assignee: PPG Industries Ohio Inc
•
Filing: 1989-11-03
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Granted: 1991-06-11
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Expires: 2009-11-03
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Abstract

Abstract A neutral gray, low transmittance (less than 20 percent luminous transmittance) soda-lime-silica glass has reduced solar energy transmittance, and in particular exceptionally low ultraviolet transmittance (less than 20 percent total solar ultraviolet transmittance) when provided with the following colorant constituents: Fe 2 O 3 (total iron) 0.4-0.7 percent by weight FeO 0.08-0.15 Se 0.003-0.008 CoO 0.003-0.025 Cr 2 O 3 0.022-0.050 The glass avoids the use of nickel compounds as colorants. Parameters for melting such a glass in a commercial furnace are also disclosed.

Inventors

  • 👤 John F. Krumwiede
  • 👤 Paul W. Kopp
  • 👤 Robert B. Heithoff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 12:59
CPC Classifications
C; C03; C03C; C03C4/00; C03C4/08; C03C4/02; C03C3/00; C03C3/04; C03C3/076; C03C3/078; C03C3/083; C03C3/085; C03C3/087; Y; Y10; Y10S; Y10S501/00; Y10S501/90; Y10S501/904; Y10S501/905

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 97 words
A neutral gray colored glass composition having a base glass composition comprising: SiO 2 68-75 percent by weight Na 2 O 10-18 CaO 5-15 MgO 0-5 Al 2 O 3 0-5 K 2 O 0-5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe 2 O 3 (total iron) 0.4-0.7 percent by weight FeO 0.08-0.15 Se 0.003-0.008 CoO 0.003-0.025 Cr 2 O 3 0.022-0.050 the glass having a luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).
Claim 2
Dependent Claim 97 words
A neutral gray colored glass composition having a base glass composition comprising: SiO 2 68-75 percent by weight Na 2 O 10-18 CaO 5-15 MgO 0-5 Al 2 O 3 0-5 K 2 O 0-5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe 2 O 3 (total iron) 0.4-0.7 percent by weight FeO 0.08-0.15 Se 0.003-0.008 CoO 0.003-0.025 Cr 2 O 3 0.022-0.050 the glass having a luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).
Claim 3
Dependent Claim 30 words
The composition of claim 1 wherein the colorant portion consists essentially of: Fe 2 O 3 (total iron) 0.5-0.6 FeO 0.08-0.11 Se 0.004-0.007 CoO 0.010-0.020 Cr 2 O 3 0.027-0.045.
Claim 4
Dependent Claim 25 words
The composition of claim 1 wherein the glass at a thickness of 0.219 inch (5.56 millimeters) has total solar ultraviolet transmittance less than 10 percent.
Claim 5
Dependent Claim 25 words
The composition of claim 1 wherein the glass at a thickness of 0.219 inch (5.56 millimeters) has total solar ultraviolet transmittance less than 15 percent.
Claim 6
Dependent Claim 99 words
An article of manufacture comprising a glass sheet having a base glass composition comprising: SiO 2 68-75 percent by weight Na 2 O 10-18 CaO 5-15 MgO 0-5 Al 2 O 3 0-5 K 2 O 0-5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe 2 O 3 (total iron) 0.4-0.7 percent by weight FeO 0.08-0.15 Se 0.003-0.008 CoO 0.003-0.025 Cr 2 O 3 0.022-0.050 the glass having a luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).
Claim 7
Dependent Claim 99 words
An article of manufacture comprising a glass sheet having a base glass composition comprising: SiO 2 68-75 percent by weight Na 2 O 10-18 CaO 5-15 MgO 0-5 Al 2 O 3 0-5 K 2 O 0-5 and traces of melting and refining aids, if any, and colorants consisting essentially of: Fe 2 O 3 (total iron) 0.4-0.7 percent by weight FeO 0.08-0.15 Se 0.003-0.008 CoO 0.003-0.025 Cr 2 O 3 0.022-0.050 the glass having a luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).
Claim 8
Dependent Claim 34 words
The glass sheet of claim 5 wherein the colorant portion of the glass sheet consists of: Fe 2 O 3 (total iron) 0.5-0.6 FeO 0.08-0.11 Se 0.004-0.007 CoO 0.010-0.020 Cr 2 O 3 0.027-0.045.
Claim 9
Dependent Claim 14 words
The glass sheet of claim 5 having a thickness of 2 to 10 millimeters.
Claim 10
Dependent Claim 14 words
The glass sheet of claim 5 having a thickness of 3 to 6 millimeters.
Claim 11
Dependent Claim 17 words
The glass sheet of claim 5 wherein the total solar ultraviolet transmittance is less than 15 percent.
Claim 12
Dependent Claim 17 words
The glass sheet of claim 5 wherein the total solar ultraviolet transmittance is less than 15 percent.
Claim 13
Independent Claim 156 words
A method of making low transmittance soda-lime-silica glass comprising: melting a batch mixture proportioned to yield a soda-lime-silica glass having at least 0.4 percent by weight total iron measured as Fe 2 O 3 including at least 0.08 weight percent FeO, at least 0.022 percent by weight Cr 2 O 3 , at least 0.003 weight percent CoO, and at least 0.003 percent Se; limiting the amount of sulfur-containing refining aid included in the batch mixture to an amount equivalent to no more than 10 parts by weight sodium sulfate per 1000 parts by weight of sand in the batch mixture; and including in the batch mixture a carbon source equivalent to at least 0.5 parts by weight coal per 1000 parts by weight sand in the batch mixture, whereby the glass has luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).
Claim 14
Independent Claim 156 words
A method of making low transmittance soda-lime-silica glass comprising: melting a batch mixture proportioned to yield a soda-lime-silica glass having at least 0.4 percent by weight total iron measured as Fe 2 O 3 including at least 0.08 weight percent FeO, at least 0.022 percent by weight Cr 2 O 3 , at least 0.003 weight percent CoO, and at least 0.003 percent Se; limiting the amount of sulfur-containing refining aid included in the batch mixture to an amount equivalent to no more than 10 parts by weight sodium sulfate per 1000 parts by weight of sand in the batch mixture; and including in the batch mixture a carbon source equivalent to at least 0.5 parts by weight coal per 1000 parts by weight sand in the batch mixture, whereby the glass has luminous transmittance less than 20 percent and total solar ultraviolet transmittance less than 20 percent at a thickness of 0.219 inch (5.56 millimeters).

References Cited (Backward Citations)

US2524719A Cited
US2892726A Cited
USRE25312E Cited
US3296004A Cited
US3300323A Cited
US3723142A Cited
US4104076A Cited
GB1331492A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-06-10 1994-12-10 1995-06-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-06-10 1998-12-10 1999-06-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-06-10 2002-12-10 2003-06-11 $7700.00 Window Closed / Lapsed

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