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X-Ray absorbing glass for a color cathode ray tube having a controlled chromaticity value and a selective light absorption

Assignee: Nippon Electric Glass Co Ltd
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Filing: 1981-09-09
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Granted: 1983-06-28
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Expires: 2001-09-09
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Abstract

Abstract A panel glass of a color cathode ray tube exhibiting a high absorption of X-radiation and an excellent resistance to electron and/or X-ray browning, which is modified by 0.1-5.0 wt % Nd 2 0 3 to provide substantially higher relative light transmission in the green and in the red wavelengths of the visible spectrum and a greater selective light absorption in the yellow region of the spectrum, and which is further modified by 0.0005-0.05 wt % Cr 2 O 3 and 0-2 wt % Pr 6 O 11 to control the chromaticity value of the glass to be nearly equal to that of the light emitted from tricolor phosphor P22 and to suppress the dichroism of the glass for different ambient lights. Ingredients of the glass are as follows: 50-75% SiO 2 , 0-5% Al 2 O 3 , 0-4% CaO, 0-3% MgO, 0-13% SrO, 0-16% BaO, 0-3% PbO, O-3% ZnO, 0-4% ZrO 2 , the sum of SrO+BaO+PbO+ZnO+ZrO 2 being 5-25%, 0-4% Li 2 O, 3-15% Na 2 O, 2-15% K 2 O, the sum of Na 2 O+K 2 O being 5-20%, O-2%, TiO 2 , O-3% CeO 2 , 0.1-5.0% Nd 2 O 3 , 0.0005-0.05% Cr 2 O 3 , and 0-2% Pr 6 O 11 .

Inventors

  • 👤 Nobutaka Daiku

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:37
CPC Classifications
C; C03; C03C; C03C4/00; C03C4/08; C03C3/00; C03C3/04; C03C3/076; C03C3/095; C03C4/087; H; H01; H01J; H01J29/00; H01J29/86; H01J29/863

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 99 words
A glass for use in color cathode ray tube having the composition essentially consisting, by weight, of 50-75% SiO 2 , 0-5% Al 2 O 3 , 0-4% CaO, 0-3% MgO, 0-13% SrO, 0-16% BaO, 0-3% PbO, 0-3% ZnO, 0-4% ZrO 2 , the sum of SrO+BaO+PbO+ZnO+ZrO 2 being 5-25%, 0-4% Li 2 O, 3-15% Na 2 O, 2-15% K 2 O, the sum of Na 2 O+K 2 O being 5-20%, 0-2% TiO 2 , 0-3% CeO 2 , 0.1-5.0% Nd 2 O 3 , 0.0005-0.05% Cr 2 O 3 , and 0-2% Pr 6 O 11 .
Claim 2
Dependent Claim 99 words
A glass for use in color cathode ray tube having the composition essentially consisting, by weight, of 50-75% SiO 2 , 0-5% Al 2 O 3 , 0-4% CaO, 0-3% MgO, 0-13% SrO, 0-16% BaO, 0-3% PbO, 0-3% ZnO, 0-4% ZrO 2 , the sum of SrO+BaO+PbO+ZnO+ZrO 2 being 5-25%, 0-4% Li 2 O, 3-15% Na 2 O, 2-15% K 2 O, the sum of Na 2 O+K 2 O being 5-20%, 0-2% TiO 2 , 0-3% CeO 2 , 0.1-5.0% Nd 2 O 3 , 0.0005-0.05% Cr 2 O 3 , and 0-2% Pr 6 O 11 .
Claim 3
Dependent Claim 70 words
A glass as claimed in claim 1, wherein said composition comprises, by weight, 55-70% SiO 2 , 0.5-4% Al 2 O 3 , 0-3% CaO, 0-2% MgO, 10-23% of SrO+BaO+PbO+ZnO+ZrO 2 , 0-2.5% Li 2 O, 10-19% of Na 2 O+K 2 O, 0-1% TiO 2 , 0.1-1% CeO 2 , 0.3-5% Nd 2 O 3 , 0.0006-0.03% Cr 2 O 3 , and 0-1.5% Pr 6 O 11 .
Claim 4
Dependent Claim 26 words
A glass as claimed in claim 1, wherein the amount of said neodium oxide (Nd 2 O 3 ) is 0.3-5% by weight of the glass.
Claim 5
Dependent Claim 21 words
A glass as claimed in claim 1, wherein the amount of said chromium oxide is 0.0006-0.03% by weight of the glass.
Claim 6
Dependent Claim 21 words
A glass as claimed in claim 1, wherein the amount of said praseodymium oxide is 0-1.5% by weight of the glass.

References Cited (Backward Citations)

US2378769A Cited
US3143683A Cited
GB1154500A Cited
DE1286539B Cited
US3464932A Cited
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SU451642A1 Cited
US3987330A Cited
GB2057422B Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-06-27 1986-12-27 1987-06-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-06-27 1990-12-27 1991-06-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-06-27 1994-12-27 1995-06-28 $7700.00 Window Closed / Lapsed

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