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Infrared transparent glass ceramic articles with beta-quarts solid solution crystals without any other crystals

Assignee: Nippon Electric Glass Co Ltd
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Filing: 1987-02-04
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Granted: 1989-05-30
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Expires: 2007-02-04
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Abstract

Abstract An infrared transparent glass ceramic article is useful for top plates of cooking stoves and has a black appearance but an infrared transmittance of about 80% or more for an infrared light of a wavelength 1,500 nm, and β-quartz solid solution crystals substantially alone dispersed within glassy matrix without any other crystals. The article consists essentially, by weight, of 60-72% SiO 2 , 14-28% Al 2 O 3 , 2.5-5.5% Li 2 O, 0.1-0.9% MgO, 0.1-0.9% ZnO, 3-6% TiO 2 , 0.03-0.5% V 2 O 5 , 0.1-1% Na 2 O, 0-1% K 2 O, 0-2% CaO, 0-2% BaO, 0-2% PbO, 0-2% As 2 O 3 , 0-3% ZrO 2 , and 0-3% P d O 5 . The article is produced by forming a desired shape of glass article having the ingredients, heating the glass article at a temperature of 650°-800° C. to nucleate in the glass, heating the glass article at a temperature of 800°-950° C. to thereby precipitate β-quartz solid solution crystals alone in the glass, and cooling the article to the room temperature.

Inventors

  • 👤 Takehiro Shibuya
  • 👤 Kazuhiro Matsui
  • 👤 Makoto Matsumoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 13:42
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/68; H05B3/74; C; C03; C03C; C03C10/00; C03C10/0018; C03C10/0027; C03C10/0036; C03C10/0045; C03C4/00; C03C4/10; Y; Y02; Y02B; Y02B30/00

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 152 words
An infrared transparent glass ceramic article having a bending strength of 20,000 psi or more, displaying, in thickness of about 3mm, a transmittance of about 5% or less for visible light of a wavelength of 500nm or less but a transmittance of about 80% or more for an infrared light of a wavelength of 1,500nm, and a dark or black appearance, and consisting of a glassy matrix and β-quartz solid solution crystals substantially alone dispersed within the glassy matrix, said glass ceramic article being free from Fe 2 O 3 and consisting essentially, by weight, of 60-72% SiO 2 , 14-28% Al 2 O 3 2.5-5.5% Li 2 O, 0.1-0.9% MgO, 0.1-0.9% ZnO, 3-6% TiO 2 , 0.03-0.2% V 2 O 5 , 0.1-1% Na 2 O, 0-1% K 2 O, 0-2% BaO, 0-2% PbO, 0-2% As 2 O 3 , 0-3% ZrO 2 , and 0-3% P 2 O 5 .
Claim 2
Dependent Claim 152 words
An infrared transparent glass ceramic article having a bending strength of 20,000 psi or more, displaying, in thickness of about 3mm, a transmittance of about 5% or less for visible light of a wavelength of 500nm or less but a transmittance of about 80% or more for an infrared light of a wavelength of 1,500nm, and a dark or black appearance, and consisting of a glassy matrix and β-quartz solid solution crystals substantially alone dispersed within the glassy matrix, said glass ceramic article being free from Fe 2 O 3 and consisting essentially, by weight, of 60-72% SiO 2 , 14-28% Al 2 O 3 2.5-5.5% Li 2 O, 0.1-0.9% MgO, 0.1-0.9% ZnO, 3-6% TiO 2 , 0.03-0.2% V 2 O 5 , 0.1-1% Na 2 O, 0-1% K 2 O, 0-2% BaO, 0-2% PbO, 0-2% As 2 O 3 , 0-3% ZrO 2 , and 0-3% P 2 O 5 .

References Cited (Backward Citations)

US4211820A Cited
US4461839A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-05-29 1992-11-28 1993-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-05-29 1996-11-28 1997-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-05-29 2000-11-28 2001-05-30 $7700.00 Window Closed / Lapsed

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