US4940677A
Expired / Lapsed
US
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Zinc-containing phosphate glasses
Assignee: Corning Inc
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Filing: 1989-12-26
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Granted: 1990-07-10
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Expires: 2009-12-26
Abstract
Abstract This invention is directed to the preparation of glasses exhibiting a transition temperature below 450° C., a working temperature below 500° C., and excellent resistance to attack by water and mild aqueous alkaline solutions. The glasses consist essentially, in mole percent, of at least 65% total of 23-55% ZnO, 28-40% P 2 O 5 , and 10-35% R 2 O, wherein R 2 O consists of at least two alkali metal oxides in the indicated proportions selected from the group consisting of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O, and up to 35% total of optional ingredients in the indicated proportions selected from the group consisting of 0-6% Al 2 O 3 , 0-8% B 2 O 3 , 0-8% Al 2 O 3 +B 2 O 3 , 0-15% Cu 2 O, 0-5% F, 0-35% PbO, 0-35% SnO, 0-35% PbO+SnO, 0-5% ZrO 2 , 0-4% SiO 2 , and 0-15% MgO+CaO+SrO+BaO+MnO, consisting of 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-12% BaO, and 0- 10% MnO.
Inventors
- 👤 George H. Beall
- 👤 Candace J. Quinn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:04
CPC Classifications
C; C03; C03C; C03C3/00; C03C3/12; C03C3/16; C03C3/17; C03C3/19
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
171 words
A glass exhibiting a transition temperature below 450° C., a working temperature below 500° C., and excellent resistance to attack by water and mild aqueous alkaline solutions, said glass consisting essentially, expressed in terms of mole percent on the oxide basis, of at least 65% total of 23-55% ZnO, 28-40% P 2 O 5 , and 10-35% R 2 O, wherein R 2 O consists of at least two alkali metal oxides in the indicated proportions selected from the group consisting of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O, and up to 35% total of optional ingredients in the indicated proportions selected from the group consisting of 0-6% Al 2 O 3 , 0-8% B 2 O 3 , 0-8% Al 2 O 3 +B 2 O 3 , 0-15% Cu 2 O, 0-5% F, 0-35% PbO, 0-35% SnO, 0-35% PbO+SnO, 0-5% ZrO 2 , 0-4% SiO 2 , and 0-15% MgO+CaO+SrO+BaO+MnO, consisting of 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-12% BaO, and 0-10% MnO.
Claim 2
Dependent Claim
171 words
A glass exhibiting a transition temperature below 450° C., a working temperature below 500° C., and excellent resistance to attack by water and mild aqueous alkaline solutions, said glass consisting essentially, expressed in terms of mole percent on the oxide basis, of at least 65% total of 23-55% ZnO, 28-40% P 2 O 5 , and 10-35% R 2 O, wherein R 2 O consists of at least two alkali metal oxides in the indicated proportions selected from the group consisting of 0-25% Li 2 O, 0-25% Na 2 O, and 0-25% K 2 O, and up to 35% total of optional ingredients in the indicated proportions selected from the group consisting of 0-6% Al 2 O 3 , 0-8% B 2 O 3 , 0-8% Al 2 O 3 +B 2 O 3 , 0-15% Cu 2 O, 0-5% F, 0-35% PbO, 0-35% SnO, 0-35% PbO+SnO, 0-5% ZrO 2 , 0-4% SiO 2 , and 0-15% MgO+CaO+SrO+BaO+MnO, consisting of 0-10% MgO, 0-10% CaO, 0-10% SrO, 0-12% BaO, and 0-10% MnO.
Claim 3
Dependent Claim
32 words
A glass according to claim 1 containing 0.75-6% Al 2 O 3 and/or 1-8% B 2 O 3 , the total Al 2 O 3 +B 2 O 3 not exceeding 8%.
Claim 4
Dependent Claim
49 words
A glass according to claim 1 containing 30-55% ZnO, 30-38% P 2 O 5 , 0-4% Al 2 O 3 , 0-10% PbO, 0-10% SnO, and 10-30% R 2 O, wherein R 2 O consists of 3-12% Li 2 O, 4-18% Na 2 O, and 0-12% K 2 O.
Claim 5
Dependent Claim
9 words
A glass according to claim 1 containing 0-5% CaO.
Claim 6
Dependent Claim
9 words
A glass according to claim 4 containing 6-15% CaO+BaO.
Claim 7
Dependent Claim
30 words
A glass according to claim 1 wherein the sum of R 2 O+Al 2 O 3 and/or B 2 O 3 +ZnO+P 2 O 5 +PbO+SnO totals at least 85%.
Claim 8
Dependent Claim
25 words
A glass according to claim 3 wherein the sum of R 2 O+Al 2 O 3 +ZnO+P 2 O 5 +PbO+SnO totals at least 85%.
Claim 9
Dependent Claim
78 words
A glass according to claim 3 consisting essentially of 12-25% R 2 O, wherein R 2 O consists of at least two alkali metal oxides in the indicated proportions of 3-12% Li 2 O, 4-13% Na 2 O, and 0-12% K 2 O, 30-49% ZnO, 1-3.5% Al 2 O 3 , 30-36% P 2 O 5 , and 0-10% SnO, the sum of R 2 O+Al 2 O 3 +ZnO+P 2 O 5 +SnO totals at least 85%.
References Cited (Backward Citations)
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