Patent US2694994A successfully refreshed from Google Patents.
US4472200A
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New additives for retarding setting of cement from methylenephosphonated aminohydrocarbylpiperazine-urea adducts
Assignee: Dow Chemical Co
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Filing: 1983-09-02
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Granted: 1984-09-18
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Expires: 2003-09-02
Abstract
Abstract Certain methylenephosphonic acid derivatives of aminohydrocarbylpiperazine-urea adducts have been found to be good cement set-retarding additives.
Inventors
- 👤 Druce K. Crump
- 👤 David A. Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:17
CPC Classifications
C; C04; C04B; C04B24/00; C04B24/003; C07; C07F; C07F9/00; C07F9/02; C07F9/547; C07F9/645; C07F9/6509; C07F9/650952; C07F9/6558; C07F9/65583
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
69 words
In a process for retarding the setting of an aqueous cement slurry which comprises adding to said slurry an organic phosphonate, the improvement which comprises employing a compound of the formula ##STR5## wherein A is ##STR6## wherein X is ##STR7## or H, and R is H, ammonium, an alkali or alkaline earth metal, m is 0-2, n is 2 or 3, and wherein at least one X is ##STR8##
Claim 2
Dependent Claim
69 words
In a process for retarding the setting of an aqueous cement slurry which comprises adding to said slurry an organic phosphonate, the improvement which comprises employing a compound of the formula ##STR5## wherein A is ##STR6## wherein X is ##STR7## or H, and R is H, ammonium, an alkali or alkaline earth metal, m is 0-2, n is 2 or 3, and wherein at least one X is ##STR8##
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein A is ##STR9## and m is 0.
Claim 4
Dependent Claim
9 words
The process of claim 1 wherein A is X.
Claim 5
Dependent Claim
12 words
The process of claim 2 wherein half the X substituents are hydrogen.
Claim 6
Dependent Claim
12 words
The process of claim 3 wherein half the X substituents are hydrogen.
Claim 7
Dependent Claim
13 words
The process of claim 1 wherein each R is an alkaline earth metal.
Claim 8
Dependent Claim
13 words
The process of claim 2 wherein each R is an alkaline earth metal.
Claim 9
Dependent Claim
13 words
The process of claim 3 wherein each R is an alkaline earth metal.
Claim 10
Dependent Claim
14 words
The process of claim 2 wherein each R is an alkali metal or ammonium.
Claim 11
Dependent Claim
14 words
The process of claim 3 wherein each R is an alkali metal or ammonium.
Claim 12
Dependent Claim
14 words
The process of claim 4 wherein the R groups are an alkaline earth metal.
Claim 13
Dependent Claim
14 words
The process of claim 5 wherein the R groups are an alkaline earth metal.
Claim 14
Dependent Claim
12 words
The process of claim 7 wherein the alkaline earth metal is calcium.
Claim 15
Dependent Claim
12 words
The process of claim 8 wherein the alkaline earth metal is calcium.
Claim 16
Dependent Claim
12 words
The process of claim 11 wherein the alkaline earth metal is calcium.
Claim 17
Dependent Claim
12 words
The process of claim 12 wherein the alkaline earth metal is calcium.
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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) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |