PbO-containing sealing glass with higher oxide of a cation to avoid PbO reduction
First Claim
1. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass frit is unreduced when said sealing glass frit is fired in the presence of reducing conditions and at temperatures at which said sealing glass frit seals said glass surfaces together, said improvement comprising incorporating in said sealing glass frit a sufficient amount of a powder of a higher oxide of a cation which is stable at the temperatures at which said sealing glass frit seals said glass surfaces together and which can be reduced to a lower oxide of the cation when exposed to said reducing conditions, said lower oxide of said cation being compatible with the fired sealing glass, said higher oxide of said cation being selected from the group consisting of Pb3 O4, BaO2, MnO2, Mn2 O3, Fe3 O4, CuO, Cu2 O, Tl2 O3, TeO2, Ta2 O5, Nb2 O5, V2 O5, CeO2 and Bi2 O3.
1 Assignment
0 Petitions
Accused Products
Abstract
A sealing glass and a sealing glass paste for sealing the face plate and funnel portion of a color television tube wherein PbO-containing sealing glass frit contains an effective amount of a powder, such as Pb3 O4 powder, which powder prevents the reduction of PbO to Pb metal during the sealing process, which reduction would otherwise result in a dielectric breakdown in the seal. Among other powders similarly found to be effective for the purpose of prevention of reduction of PbO in a PbO-containing sealing glass frit are certain other higher oxides of a cation which are selected from a group including, in addition to Pb3 O4, such higher oxides of a cation as BaO2, CrO3, MnO2, Mn2 O3, Fe2 O3, Fe3 O4, CuO, Cu2 O, Tl2 O3, Sb2 O5, TeO2, Ta2 O5, Nb2 O5, V2 O5, CeO2, Bi2 O3 and As2 O5. A sealing glass paste consisting essentially of a PbO-- B2 O3 --ZnO sealing glass frit and containing an effective amount of said powder, based upon the weight of the frit, together with hydroxypropyl cellulose binder for the frit and a solvent for the binder. A method for sealing the face plate of a color television tube to its funnel portion with a PbO-containing solder glass wherein the reduction of PbO to metallic lead during the sealing step is obviated by the addition of a sufficient amount of Pb3 O4, BaO2 or other of the mentioned higher oxide of a cation powder in the solder glass and paste made therewith, which Pb3 O4, BaO2 or other of the mentioned higher oxides of a cation will be slowly reduced to a lower oxide in a reducing atmosphere during the sealing of the television tube components. A method for increasing the dielectric properties of a PbO-containing sealing glass paste and the devitrified seal made therefrom, which seals the face plate to the funnel of a color television tube, to a value greater than that provided by the solder glass, per se, by incorporating in the solder glass and the solder glass paste made therefrom a small but sufficient amount of Pb3 O4, BaO2 or other of the mentioned higher oxide of a cation powders to accomplish this purpose. A vehicle for a glass frit comprises hydroxypropyl cellulose as a binder and a solvent for said binder.
46 Citations
98 Claims
- 1. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass frit is unreduced when said sealing glass frit is fired in the presence of reducing conditions and at temperatures at which said sealing glass frit seals said glass surfaces together, said improvement comprising incorporating in said sealing glass frit a sufficient amount of a powder of a higher oxide of a cation which is stable at the temperatures at which said sealing glass frit seals said glass surfaces together and which can be reduced to a lower oxide of the cation when exposed to said reducing conditions, said lower oxide of said cation being compatible with the fired sealing glass, said higher oxide of said cation being selected from the group consisting of Pb3 O4, BaO2, MnO2, Mn2 O3, Fe3 O4, CuO, Cu2 O, Tl2 O3, TeO2, Ta2 O5, Nb2 O5, V2 O5, CeO2 and Bi2 O3.
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9. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising incorporating in said sealing glass an amount of Pb3 O4 powder sufficient to prevent reduction of the PbO in said sealing glass during sealing in the presence of said reducing conditions.
- View Dependent Claims (14, 15, 16, 17, 18)
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15. A sealing glass frit as defined in claim 14, wherein said powder is present in an amount of from about 0.2 to about 1.5% by weight of said sealing glass frit.
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16. A sealing glass frit according to claim 9 in which said frit consists essentially of:
space="preserve" listing-type="tabular">CONSTITUENTS PERCENT BY WEIGHT ______________________________________ PbO 75 ZnO 12.6 B.sub.2 O.sub.3 8.3 SiO.sub.2 2.1 BaO 2. . ______________________________________
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17. A sealing glass frit according to claim 9 in which said frit consists essentially of:
space="preserve" listing-type="tabular">CONSTITUENTS PERCENT BY WEIGHT ______________________________________ PbO 84 ZnO 2.7 B.sub.2 O.sub.3 12.3 SiO.sub.2 0.4 BaO 0.6. ______________________________________
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18. A sealing glass frit according to claim 9 consisting essentially of:
space="preserve" listing-type="tabular">CONSTITUENTS PERCENTAGE BY WEIGHT ______________________________________ PbO 75 - 82 ZnO 7 - 14 B.sub.2 O.sub.3 6.5 - 12 SiO.sub.2 1.5 - 3 . ______________________________________
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10. A PbO-containing sealing glass frit having incorporated therein from about 0.1 to 1.5% Pb3 O4 powder based upon the weight of said sealing glass frit.
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11. A sealing glass frit consisting essentially of:
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space="preserve" listing-type="tabular">CONSTITUENTS PERCENT BY WEIGHT ______________________________________ PbO 75 - 82 ZnO 7 - 14 B.sub.2 O.sub.3 6.5 - 12 SiO.sub.2 1.5 - 3 ______________________________________and having incorporated therein from about 0.1 to 1.5% Pb3 O4 powder based upon the weight of said sealing glass frit. - View Dependent Claims (12, 13)
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19. In a PbO-containing seaing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions and at temperatures from about 400°
- C at which said sealing glass frit seals said glass surfaces together, said improvement comprising incorporating in said sealing glass an amount of BaO2 powder sufficient to prevent reduction of the PbO in said sealing glass during sealing in the presence of said reducing conditions.
- View Dependent Claims (20)
- 21. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of BaO2 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 27. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of MnO2 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 33. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Mn2 O3 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 39. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Fe3 O4 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 45. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of CuO powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 51. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealng glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Cu2 O powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 57. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Tl2 O3 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 63. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of TeO2 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 69. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO is said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit and amount of Ta2 O5 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 75. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Nb2 O5 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 81. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of V2 O5 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 87. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of CeO2 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
- 93. In a PbO-containing sealing glass frit for sealing two glass surfaces together, the improvement wherein the PbO in said sealing glass is prevented from being reduced when said sealing glass is being fired in the presence of reducing conditions at a temperature sufficient to seal said glass surfaces together, said improvement comprising having intermixed with said sealing glass frit an amount of Bi2 O3 powder sufficient to prevent reduction of the PbO in said sealing glass frit during sealing in the presence of said reducing conditions.
Specification
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- Resources
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Current AssigneeTechneglas LLC (Nippon Electric Glass Company Limited)
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Original AssigneeOwens-Illinois Incorporated (O-I Glass, Inc.)
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InventorsKing, James E., Francel, Josef, Woulbroun, John M.
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Primary Examiner(s)Douglas, Winston A.
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Assistant Examiner(s)Bell, Mark
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Application NumberUS05/516,900Time in Patent Office658 DaysField of Search106/53US Class Current501/15CPC Class CodesC03C 27/00 Joining pieces of glass to ...C03C 27/06 Joining glass to glass by p...C03C 27/10 with the aid of adhesive sp...C03C 3/0745 containing more than 50% le...C03C 8/245 containing more than 50% le...
