US4298392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Accelerator for setting of cements
Assignee: Akzona Inc
•
Filing: 1980-06-05
•
Granted: 1981-11-03
•
Expires: 2000-06-05
Abstract
Abstract The present disclosure relates to a class of additives for hydraulic cement which accelerate the setting of the cement. More particularly the present invention relates to an additive for Portland cement comprising a silica sol and one or more rhodanides and to cementitious compositions containing such additives.
Inventors
- 👤 Piet H. Isselmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:54
CPC Classifications
C; C04; C04B; C04B22/00; C04B22/08; C04B22/14; C04B28/00; C04B28/02; C04B28/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
38 words
An additive for hydraulic cement comprising of a silica sol and one or more compounds of the formula R--S--C.tbd.N wherein for each compound, R is independently selected from the class consisting of alkali metals and alkaline earth metals.
Claim 2
Dependent Claim
38 words
An additive for hydraulic cement comprising of a silica sol and one or more compounds of the formula R--S--C.tbd.N wherein for each compound, R is independently selected from the class consisting of alkali metals and alkaline earth metals.
Claim 3
Dependent Claim
26 words
An additive according to claim 1 wherein for each compound of the formula R--S--C.tbd.N R is independently selected from the group consisting of calcium and sodium.
Claim 4
Dependent Claim
10 words
An additive according to claim 2 wherein R is sodium.
Claim 5
Dependent Claim
39 words
An additive according to claim 1 or 2 wherein the weight ratio between the amount of compounds of the formula R--S--C.tbd.N and the amount of silica sol, calculated as SiO 2 is in the range of 1:2 to 5:1.
Claim 6
Dependent Claim
37 words
An additive according to claim 4 wherein the weight ratio between the amount of compounds of the formula R--S--C.tbd.N and the amount of silica sol, calculated as SiO 2 is in the range of 4:1 to 1:1.
Claim 7
Dependent Claim
37 words
An additive according to claim 5 wherein the weight ratio between the amount of compounds of the formula R--S--C.tbd.N and the amount of silica sol, calculated as SiO 2 is in the range of 3.5:1 to 1.5:1.
Claim 8
Dependent Claim
44 words
A cementing composition comprising of a hydraulic cement and an additive comprising of a silica sol and one or more compounds of the formula R--S--C.tbd.N wherein for each compound, R is independently selected from the class consisting of alkali metals and alkaline earth metals.
Claim 9
Dependent Claim
44 words
A cementing composition comprising of a hydraulic cement and an additive comprising of a silica sol and one or more compounds of the formula R--S--C.tbd.N wherein for each compound, R is independently selected from the class consisting of alkali metals and alkaline earth metals.
Claim 10
Dependent Claim
14 words
A cementing composition according to claim 7 wherein the hydraulic cement is Portland cement.
Claim 11
Dependent Claim
44 words
A cementing composition according to claim 8 containing from 0.3% to 4.0% by weight of the hydraulic cement of an additive calculated as the sum of the amount of silica sol, calculated as SiO 2 and the amount of compounds of the formula R--S--C.tbd.N
Claim 12
Dependent Claim
44 words
A cementing composition according to claim 9 containing from 0.25% to 0.35% by weight of the hydraulic cement of an amount of silica sol calculated as SiO 2 and from 0.8% to 1.2% by weight of an amount of compounds of the formula R--S--C.tbd.N
Claim 13
Dependent Claim
27 words
A cementing composition according to claim 10 wherein for each compound of the formula R--S--C.tbd.N R is independently selected from the group consisting of calcium and sodium.
Claim 14
Dependent Claim
11 words
A cementing composition according to claim 11 wherein R is sodium.
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) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |