US4186023A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sealing glass composition
Assignee: Technology Glass Corp
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Filing: 1978-05-01
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Granted: 1980-01-29
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Expires: 1998-05-01
Abstract
Abstract Lead borate and lead zinc borate glasses containing from 0.1 to 10% by weight cuprous oxide (Cu 2 O) and fluoride, the molar ratio of cuprous oxide to fluoride being in the range 1:0.25 to 1:10, preferably in the range 1:1 to 1:5, and up to 5% by weight bismuth oxide. These glasses may be mixed with particulate refractory fillers in amounts up to about 56% by volume. The sealing glasses are useful for bonding ceramic, glass and metal parts together at low temperatures. They are especially useful as semiconductor package sealants.
Inventors
- 👤 Maurice E. Dumesnil
- 👤 Ulrich Schreier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:37
CPC Classifications
C; C03; C03C; C03C27/00; C03C12/00; C03C8/00; C03C8/24; C03C8/245; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B37/00; C04B37/02; C04B37/023; C04B37/025; C04B37/04; C04B37/042; C04B2235/00; C04B2235/65; C04B2235/656; C04B2235/6565; C04B2235/6567; C04B2237/00; C04B2237/02; C04B2237/10; C04B2237/30; C04B2237/32; C04B2237/34; C04B2237/343; C04B2237/40; C04B2237/405; C04B2237/406
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
135 words
A sealing glass comprising a homogeneous mixture of lead oxide, zinc oxide, boron oxide, bismuth oxide, silicon dioxide, cuprous oxide and a minor proportion of at least one solid non-volatile metal fluoride, the proportions being lead oxide about 75 to 85 wt %, boron oxide about 8 to 15 wt %, zinc oxide up to 10 wt %, silicon dioxide 0.75 to 2.5 wt %, bismuth oxide to 5 wt %, cuprous oxide 0.5 to 5.5 wt % and non-volatile metal fluoride in amount such that the mol ratio of cuprous oxide to the fluoride content of the metal fluoride is in the range 1:0.25 to 1:10, said sealing glass being non-devitrifiable in that essentially no crystallization occurs when the glass is exposed to a temperature of 430° C. for a period of 15 minutes.
Claim 2
Dependent Claim
135 words
A sealing glass comprising a homogeneous mixture of lead oxide, zinc oxide, boron oxide, bismuth oxide, silicon dioxide, cuprous oxide and a minor proportion of at least one solid non-volatile metal fluoride, the proportions being lead oxide about 75 to 85 wt %, boron oxide about 8 to 15 wt %, zinc oxide up to 10 wt %, silicon dioxide 0.75 to 2.5 wt %, bismuth oxide to 5 wt %, cuprous oxide 0.5 to 5.5 wt % and non-volatile metal fluoride in amount such that the mol ratio of cuprous oxide to the fluoride content of the metal fluoride is in the range 1:0.25 to 1:10, said sealing glass being non-devitrifiable in that essentially no crystallization occurs when the glass is exposed to a temperature of 430° C. for a period of 15 minutes.
Claim 3
Dependent Claim
19 words
The composition of claim 1 wherein the zinc oxide content is in the range 3 to 8 wt %.
Claim 4
Dependent Claim
20 words
The composition defined in claim 2 wherein the bismuth oxide content is in the range 1 to 5 wt %.
Claim 5
Dependent Claim
30 words
The composition defined in claim 1 or claim 2 wherein the metal fluoride is lead fluoride, cuprous fluoride, zinc fluoride or mixtures of at least two of said metal fluorides.
Claim 6
Dependent Claim
40 words
The composition of claim 1 having a finely divided refractory material characterized by a linear coefficient of expansion below 100×10-7/°C. dispersed in it, said refractory material being present in amount sufficient to constitute up to 56 vol% of the dispersion.
Claim 7
Dependent Claim
40 words
The composition of claim 2 having a finely divided refractory material characterized by a linear coefficient of expansion below 100×10-7/°C. dispersed in it, said refractory being present in amount sufficient to constitute up to 56 vol % of the dispersion.
Claim 8
Dependent Claim
40 words
The composition of claim 3 having a finely divided refractory material characterized by a linear coefficient of expansion below 100×10-7/°C. dispersed in it, said refractory being present in amount sufficient to constitute up to 56 vol % of the dispersion.
Claim 9
Dependent Claim
43 words
A mixture consisting essentially of particles of the sealing glass defined in claims 1, 2 or 3 and finely divided refractory material having a coefficient of linear expansion below 40×10-7/°C., the refractory material constituting from 5 to 50% by volume of the mixture.
Claim 10
Dependent Claim
29 words
A printing paste consisting of a mixture of the composition of claim 5, 6 or 7, and a thermally stable organic liquid boiling in the range about 150°-250° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-28 | 1983-07-30 | 1984-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-28 | 1987-07-30 | 1988-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-28 | 1991-07-30 | 1992-01-29 | $7700.00 | Window Closed / Lapsed |