US3238155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Addition of melamine-formaldehyde to magnesium oxycement to improve the resistance to the passage of water of said cement
Assignee: Dow Chemical Co
•
Filing: 1961-12-04
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Granted: 1966-03-01
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Expires: 1981-12-04
Abstract
No abstract record available.
Inventors
- 👤 Bob R Harrell
- 👤 Stephen P Edwards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:40
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
IN A MAGNESIA CEMENT PRODUCT COMPRISING THE REACTION PRODUCT OF MAGNESIUM OXIDE AND A MAGNESIUM SALT IN AQUEOUS SOLUTION IN PROPORTIONS OF EACH WHICH SET TO A HARD SOLID, SAID SALT BEING SELECTED FROM THE GROUP CONSISTING OF MAGNESIUM CHLORIDE AND MAGNESIUM SULFATE, THE IMPROVEMENT CONSISTING OF THE INCORPORATION THEREIN, TO INCREASE THE RESISTANCE TO THE PASSAGE OF WATER OF THE CEMENT WHEN SET, OF BETWEEN ABOUT 0.5% AND ABOUT 20%, BASED UPON THE COMBINED WEIGHTS OF THE MAGNESIUM OXIDE AND MAGNESIUM SALT PRESENT, OF A RESINOUS POLYMERIC COMPOSITION PREPARED BY POLYMERIZING A REACTION MIXTURE OF FORMALDEHYDE AND MELAMINE IN A RATIO OF BETWEEN 2 AND 6 MOLES OF FORMALDEHYDE PER MOLE OF MELAMINE.
Claim 2
Dependent Claim
114 words
IN A MAGNESIA CEMENT PRODUCT COMPRISING THE REACTION PRODUCT OF MAGNESIUM OXIDE AND A MAGNESIUM SALT IN AQUEOUS SOLUTION IN PROPORTIONS OF EACH WHICH SET TO A HARD SOLID, SAID SALT BEING SELECTED FROM THE GROUP CONSISTING OF MAGNESIUM CHLORIDE AND MAGNESIUM SULFATE, THE IMPROVEMENT CONSISTING OF THE INCORPORATION THEREIN, TO INCREASE THE RESISTANCE TO THE PASSAGE OF WATER OF THE CEMENT WHEN SET, OF BETWEEN ABOUT 0.5% AND ABOUT 20%, BASED UPON THE COMBINED WEIGHTS OF THE MAGNESIUM OXIDE AND MAGNESIUM SALT PRESENT, OF A RESINOUS POLYMERIC COMPOSITION PREPARED BY POLYMERIZING A REACTION MIXTURE OF FORMALDEHYDE AND MELAMINE IN A RATIO OF BETWEEN 2 AND 6 MOLES OF FORMALDEHYDE PER MOLE OF MELAMINE.
References Cited (Backward Citations)
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Cited
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Cited
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Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-02-28 | 1969-08-30 | 1970-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-28 | 1973-08-30 | 1974-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-28 | 1977-08-30 | 1978-03-01 | $7700.00 | Window Closed / Lapsed |