US4559239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for repairing cementitious substrate
Assignee: Individual
•
Filing: 1983-12-16
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Granted: 1985-12-17
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Expires: 2003-12-16
Abstract
Abstract A method of repairing cementitious substrates with polyurethane in which volatile-free polyurethane precursor reactants are sprayed and polymerized on the surfaces of cementitious articles, such as concrete water conduits.
Inventors
- 👤 Louis F. Cenegy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:51
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/50; B05D7/52; B05D7/54; C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/65; C08G18/66; C08G18/6666; C08G18/667; C08G18/6681; C08G18/6688; E; E04; E04D; E04D7/00; B05D2503/00; C08G2150/00; C08G2150/50
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
146 words
A method for repairing and enhancing the durability of a concrete conduit whose cement matrix has at least partially deteriorated and developed void interstices among the aggregate constituents comprising: providing a substantially volatile-free A component containing an isocyanate urethane precursor, providing a substantially volatile-free B component containing polyol and amine urethane precursors, preheating said A component to a temperature in the range from about ambient temperature to about 140° F., preheating said B component to a temperature in the range from about 110° F. to about 150° F., mixing and spraying said A and B components onto the surface of said conduit, filling said interstices adjacent said surface with said components, reacting said A and B components to form a tough polyurethane matrix in said interstices and an exterior layer adhering to said surface in a very fast gel time ranging up to about 12 seconds.
Claim 2
Independent Claim
146 words
A method for repairing and enhancing the durability of a concrete conduit whose cement matrix has at least partially deteriorated and developed void interstices among the aggregate constituents comprising: providing a substantially volatile-free A component containing an isocyanate urethane precursor, providing a substantially volatile-free B component containing polyol and amine urethane precursors, preheating said A component to a temperature in the range from about ambient temperature to about 140° F., preheating said B component to a temperature in the range from about 110° F. to about 150° F., mixing and spraying said A and B components onto the surface of said conduit, filling said interstices adjacent said surface with said components, reacting said A and B components to form a tough polyurethane matrix in said interstices and an exterior layer adhering to said surface in a very fast gel time ranging up to about 12 seconds.
Claim 3
Dependent Claim
92 words
The invention as recited in claim 1 wherein said polyols constitute from about 5 wt.% to about 45 wt.% of the total process reactants and have average molecular weights in the range from about 1,000 to about 6,000, said amines comprise N,N,N',N' tetrakis (2-hydroxypropyl) ethylenediamine having a hydroxyl number in the range from about 300 to about 900, said isocyanate comprises diphenylmethane 4,4, diisocyanate having a functionality in the range from about 2.0 to about 2.8, and said amine constitutes from about 5 wt.% to about 45 wt.% of the process reactants.
Claim 4
Independent Claim
100 words
A method for repairing and enhancing the durability of a cementitious substrate whose cement matrix has at least partially deteriorated and developed void interstices therein comprising: mixing a substantially volatile-free polyurethane A component precursor and a substantially volatile-free polyurethane B component precursor, spraying said polyurethane precursors onto the surface of said cementitious substrate, filling said interstices adjacent said surface with said precursors, and reacting said A component and B component precursors to form a tough polyurethane matrix in said interstices and an exterior layer adhering to said surface in a very fast gel time ranging up to about twelve seconds.
Claim 5
Independent Claim
100 words
A method for repairing and enhancing the durability of a cementitious substrate whose cement matrix has at least partially deteriorated and developed void interstices therein comprising: mixing a substantially volatile-free polyurethane A component precursor and a substantially volatile-free polyurethane B component precursor, spraying said polyurethane precursors onto the surface of said cementitious substrate, filling said interstices adjacent said surface with said precursors, and reacting said A component and B component precursors to form a tough polyurethane matrix in said interstices and an exterior layer adhering to said surface in a very fast gel time ranging up to about twelve seconds.
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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) | 1988-12-16 | 1989-06-17 | 1989-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-16 | 1993-06-17 | 1993-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-16 | 1997-06-17 | 1997-12-17 | $7700.00 | Window Closed / Lapsed |