EP0480186A1
Expired / Lapsed
EP
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Fusion sealing materials
Assignee: Corning Inc
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Filing: 1991-09-11
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Granted: —
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Expires: 2011-09-11
Abstract
Abstract There is disclosed a sealing material based on a lead sealing glass having a mill addition of a crystalline material having the crystalline structure of magnesium pyrophosphate. The effective coefficient of thermal expansion in a seal is substantially reduced by the mill addition, thereby permitting use with low expansion materials.
Inventors
- 👤 Gaylord Lee Corning Inc. Patent Dep. Francis
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 18:32
CPC Classifications
C; C03; C03C; C03C8/00; C03C8/14; C03C8/24; C03C8/245
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
24 words
A sealing material comprising a lead sealing glass and a mill addition of a pyrophosphate crystalline material having the crystalline structure of magnesium pyrophosphate.
Claim 2
Dependent Claim
24 words
A sealing material comprising a lead sealing glass and a mill addition of a pyrophosphate crystalline material having the crystalline structure of magnesium pyrophosphate.
Claim 3
Dependent Claim
20 words
A sealing material in accordance with claim 1 wherein at least a portion of the mill addition is magnesium pyrophosphate.
Claim 4
Dependent Claim
46 words
A sealing material in accordance with claim 1 wherein at least a portion of the mill addition is magnesium pyrophosphate with a portion of the magnesium cations replaced by at least one cation selected from the group composed of cobalt, arsenic, zinc, iron, aluminum, and zirconium.
Claim 5
Dependent Claim
34 words
A sealing material in accordance with claim 1, 2, or 3 wherein the mill addition is composed of at least two different pyrophosphate crystalline materials, each material having the crystal structure of magnesium pyrophosphate.
Claim 6
Dependent Claim
43 words
A sealing material in accordance with claim 1, 2, 3 or 4, wherein at least a portion of the mill addition is a crystallized glass composed essentially of Mg0 and P 2 0 5 in about the stoichiometric molar ratio of magnesium pyrophosphate.
Claim 7
Dependent Claim
60 words
A sealing material in accordance with claim 5 wherein the crystallized glass composition further includes at least one oxide selected from the group composed of cobalt, arsenic, zinc, aluminum, iron and zirconium, and the molar ratio of the total of such selected oxide(s) plus Mg0 to the P 2 0 5 is about the stoichiometric molar ratio of magnesium pyrophosphate.
Claim 8
Dependent Claim
39 words
A sealing material in accordance with claim 1, 2, 3, 4, 5 or 6 wherein the lead sealing glass is a lead borate glass, or a lead zinc borate glass, or a lead borosilicate, or a lead titanate glass.
Claim 9
Dependent Claim
19 words
A sealing material in accordance with any one of claims 1-7 wherein the sealing material additionally contains Invar particles.
Claim 10
Dependent Claim
26 words
A sealing material in accordance with any one of claims 1-8 wherein the mill addition constitutes not more than about 20% by volume of the material.
Claim 11
Dependent Claim
17 words
The sealing material of any one of claims 1-9, characterized by its use as a fusion seal.
Claim 12
Dependent Claim
12 words
A mill addition having the characteristics of any one of claims 1-6.
References Cited (Backward Citations)
DE1596995A1
Cited
GB1552648A
Cited
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