US4084976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lead-free glaze for alumina bodies
Assignee: Federal Mogul Ignition LLC
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Filing: 1977-07-20
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Granted: 1978-04-18
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Expires: 1997-07-20
Abstract
Abstract A high-silica ceramic glaze, having a low coefficient of thermal expansion, suitable for application to alumina bodies, is disclosed. The glaze comprises, by weight percent, about 50 percent SiO 2 , from 5 to 8 percent Al 2 O 3 , from 6 to 12 percent B 2 O 3 , from 2 to 15 percent BaO, from 5 to 8 percent SrO, from 4 to 6 percent CaO, from 2 to 8 percent MgO, from 1 to 2 percent ZnO, and about 5 percent total of Na 2 O, K 2 O, Li 2 O, and minor impurities.
Inventors
- 👤 Jonathan W. Hinton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:29
CPC Classifications
C; C03; C03C; C03C8/00; C03C8/02; C03C8/04; C03C3/00; C03C3/04; C03C3/076; C03C3/089; C03C3/091; C03C3/093
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
111 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of from 50 to 54 percent by weight SiO 2 , from 5 to 8 percent by weight Al 2 O 3 , from 6 to 12 percent by weight B 2 O 3 , from 4 to 6 percent by weight CaO, from 2 to 8 percent by weight MgO, from 2 to 15 percent percent by weight BaO, from 5 to 8 percent by weight SrO, from 1 to 2 percent by weight ZnO, and from 4 to 6 percent by weight of a mixture of Na 2 O, K 2 O and Li 2 O.
Claim 2
Dependent Claim
111 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of from 50 to 54 percent by weight SiO 2 , from 5 to 8 percent by weight Al 2 O 3 , from 6 to 12 percent by weight B 2 O 3 , from 4 to 6 percent by weight CaO, from 2 to 8 percent by weight MgO, from 2 to 15 percent percent by weight BaO, from 5 to 8 percent by weight SrO, from 1 to 2 percent by weight ZnO, and from 4 to 6 percent by weight of a mixture of Na 2 O, K 2 O and Li 2 O.
Claim 3
Dependent Claim
98 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of about 52 percent by weight SiO 2 , about 6 percent by weight Al 2 O 3 , from 9 to 10 percent by weight B 2 O 3 , about 5 percent by weight CaO, from 4 to 5 percent by weight MgO, about 9 percent by weight BaO, from 6.5 to 7 percent by weight SrO, about 2 percent by weight ZnO and about 5 percent by weight of a mixture of Na 2 O, K 2 O and Li 2 O.
Claim 4
Dependent Claim
98 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of about 52 percent by weight SiO 2 , about 6 percent by weight Al 2 O 3 , from 9 to 10 percent by weight B 2 O 3 , about 5 percent by weight CaO, from 4 to 5 percent by weight MgO, about 9 percent by weight BaO, from 6.5 to 7 percent by weight SrO, about 2 percent by weight ZnO and about 5 percent by weight of a mixture of Na 2 O, K 2 O and Li 2 O.
Claim 5
Dependent Claim
35 words
A ceramic glaze as claimed in claim 2 having present about 1.7 percent by weight Na 2 O, about 3 percent by weight K 2 O and about 0.5 percent by weight Li 2 O.
Claim 6
Dependent Claim
179 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of RO, R 2 O, R 2 O 3 and R 2 , said RO consisting of MgO, CaO, SrO, BaO and ZnO, said R 2 O consisting of Li 2 O, Na 2 O and K 2 O, said R 2 O 3 consisting of B 2 O 3 and Al 2 O 3 , and wherein said RO 2 is SiO 2 , wherein the empirical molecular formula of said glaze, obtained by setting the sum of RO and R 2 O equal to one, can be expressed as 0.81 to 0.85 mole RO, from 0.15 to 0.19 mole R 2 O, from 0.4 to 0.5 mole R 2 O 3 , and from 1.8 to 2.3 moles SiO 2 , wherein ZnO is about 0.05 mole and the remaining RO total from 0.76 to 0.80 mole, of which MgO is about 0.15 to 0.37, CaO is about 0.19 to 0.23, SrO is about 0.15 to 0.16 and BaO is about 0.05 to 0.25.
Claim 7
Dependent Claim
179 words
A lead-free ceramic glaze useful for application to high alumina substrates consisting essentially of RO, R 2 O, R 2 O 3 and R 2 , said RO consisting of MgO, CaO, SrO, BaO and ZnO, said R 2 O consisting of Li 2 O, Na 2 O and K 2 O, said R 2 O 3 consisting of B 2 O 3 and Al 2 O 3 , and wherein said RO 2 is SiO 2 , wherein the empirical molecular formula of said glaze, obtained by setting the sum of RO and R 2 O equal to one, can be expressed as 0.81 to 0.85 mole RO, from 0.15 to 0.19 mole R 2 O, from 0.4 to 0.5 mole R 2 O 3 , and from 1.8 to 2.3 moles SiO 2 , wherein ZnO is about 0.05 mole and the remaining RO total from 0.76 to 0.80 mole, of which MgO is about 0.15 to 0.37, CaO is about 0.19 to 0.23, SrO is about 0.15 to 0.16 and BaO is about 0.05 to 0.25.
Claim 8
Dependent Claim
16 words
A ceramic glaze as claimed in claim 4 wherein the MgO:CaO:SrO:BaO mole ratio is about 26:21:16:14.
Claim 9
Dependent Claim
39 words
A ceramic glaze as claimed in claim 5 wherein said formula can be expressed as about 0.82 mole RO, about 0.18 mole R 2 O, about 0.46 mole R 2 O 3 and about 2 moles SiO 2 .
References Cited (Backward Citations)
US3790842A
Cited
US3927238A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-17 | 1981-10-17 | 1982-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-17 | 1985-10-17 | 1986-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-17 | 1989-10-17 | 1990-04-18 | $7700.00 | Window Closed / Lapsed |