US3292220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making shell moulds
Assignee: PQ Corp
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Filing: 1963-11-05
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Granted: 1966-12-20
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Expires: 1983-11-05
Abstract
No abstract record available.
Inventors
- 👤 Emblem Harold Garton
- 👤 Fothergill Earl Whiteway
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:36
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/165
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A METHOD OF MAKING A SHELL MOULD WHICH COMPRISES APPLYING TO AN EXPENDABLE PATTERN ALTERNATELY A COATING OF A GEL FORMING ACID-HYDROLYSED ALKYL SILICATE SOLUTION AND A COATING OF A QUATERNARY AMMONIUM SILICATE SOLUTION, AT LEAST ONE OF THE TWO SOLUTIONS HAVING REFRACTORY MATERIAL SUSPENDED THEREIN, THE QUATERNARY AMMONIUM SILICATE SOLUTION ACTING TO CAUSE THE GELATION OF THE ACID-HYDROLYSED SOLUTION.
Claim 2
Independent Claim
60 words
A METHOD OF MAKING A SHELL MOULD WHICH COMPRISES APPLYING TO AN EXPENDABLE PATTERN ALTERNATELY A COATING OF A GEL FORMING ACID-HYDROLYSED ALKYL SILICATE SOLUTION AND A COATING OF A QUATERNARY AMMONIUM SILICATE SOLUTION, AT LEAST ONE OF THE TWO SOLUTIONS HAVING REFRACTORY MATERIAL SUSPENDED THEREIN, THE QUATERNARY AMMONIUM SILICATE SOLUTION ACTING TO CAUSE THE GELATION OF THE ACID-HYDROLYSED SOLUTION.
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) | 1969-12-19 | 1970-06-20 | 1970-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-12-19 | 1974-06-20 | 1974-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-12-19 | 1978-06-20 | 1978-12-20 | $7700.00 | Window Closed / Lapsed |