US4298561A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing calcium silicate shaped product
Assignee: Mitsubishi Chemical Corp
•
Filing: 1979-11-21
•
Granted: 1981-11-03
•
Expires: 1999-11-21
Abstract
Abstract An aqueous slurry of calcium silicate hydrate which is formed by heating a siliceous source and a calcareous source in water to react them and which has the specific property is shaped with a press filter molding and cured by a steam curing under steam pressure to cause a transformation of the calcium silicate hydrate whereby a calcium silicate shaped product having low bulk density and high mechanical strength is obtained. The calcium silicate shaped product is suitable as a lagging product or a heat insulator.
Inventors
- 👤 Mitsuo Uchida
- 👤 Yasuo Oguri
- 👤 Junji Saito
- 👤 Tsukasa Kawahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:53
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/18; C04B35/00; C04B35/01; C04B35/16; C04B35/22
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
139 words
A process for preparing a calcium silicate shaped product which comprises: forming an aqueous slurry of calcium silicate hydrate of tobermorite group compounds having a wet volume of more than 15 cm 3 /g by heating at a temperature higher than 130° C. a siliceous source and a calcareous source dispersed in water to react them; shaping the aqueous slurry with a press filter molding; curing said filter slurry by a steam curing under pressure while transforming said calcium silicate hydrate from semi-crystalline or near-amorphous tobermorite to crystalline tobermorite or xonotlite; or from crystalline tobermorite to xonotlite; wherein said wet volume is given by the equation: wet volume=(V/W) wherein W represents the total weight of the calcareous source and the siliceous source, and V represents the volume of solid components after a 24 hours sedimentation of said aqueous slurry.
Claim 2
Dependent Claim
139 words
A process for preparing a calcium silicate shaped product which comprises: forming an aqueous slurry of calcium silicate hydrate of tobermorite group compounds having a wet volume of more than 15 cm 3 /g by heating at a temperature higher than 130° C. a siliceous source and a calcareous source dispersed in water to react them; shaping the aqueous slurry with a press filter molding; curing said filter slurry by a steam curing under pressure while transforming said calcium silicate hydrate from semi-crystalline or near-amorphous tobermorite to crystalline tobermorite or xonotlite; or from crystalline tobermorite to xonotlite; wherein said wet volume is given by the equation: wet volume=(V/W) wherein W represents the total weight of the calcareous source and the siliceous source, and V represents the volume of solid components after a 24 hours sedimentation of said aqueous slurry.
Claim 3
Dependent Claim
39 words
A process according to claim 1 wherein said aqueous slurry of calcium silicate hydrate is admixed with reinforcing fibrous materials and the mixture is shaped with a press filter molding and cured by the steam curing under higher pressure.
Claim 4
Dependent Claim
55 words
A process according to claim 1 wherein said aqueous slurry of calcium silicate hydrate is prepared by mixing the siliceous source and the calcareous source with reinforcing fibrous materials and heating the mixture in water and said aqueous slurry is shaped with a press filter molding and cured by the steam curing under higher pressure.
Claim 5
Dependent Claim
25 words
A process according to claim 1 wherein the reaction of the siliceous source and the calcareous source is carried out at 150° to 230° C.
Claim 6
Dependent Claim
26 words
A process according to claim 1 wherein the steam curing is carried out with steam under the steam presure of 5 to 50 Kg/cm 2 G.
Claim 7
Dependent Claim
12 words
A process according to claim 1 wherein the siliceous source is amorphous.
Claim 8
Dependent Claim
21 words
A process according to claim 1 wherein the siliceous source is a silica obtained by reacting hexafluorosilicic acid with aluminum hydroxide.
Claim 9
Dependent Claim
13 words
A process according to claim 1 wherein the siliceous source is diatomaceous earth.
Claim 10
Dependent Claim
13 words
A process according to claim 1 wherein the siliceous source is silicon dust.
Claim 11
Dependent Claim
31 words
A process according to claim 1 wherein a blast furnace slag with a water soluble inorganic alkali metal compound is used as both of the siliceous source and the calcareous source.
Claim 12
Dependent Claim
13 words
A process according to claim 1 wherein the siliceous source is ground quartzite.
Claim 13
Dependent Claim
30 words
The process of claim 1 wherein said calcium silicate shaped product has a bending strength higher than 4.3 kg/cm 2 and a bulk density lower than 0.13 g/cm 3 .
Claim 14
Dependent Claim
30 words
The process of claim 1 wherein said calcium silicate shaped product has a bending strength higher than 4.3 g/cm 2 and a bulk density lower than 0.20 g/cm 3 .
References Cited (Backward Citations)
US2105324A
Cited
US2215891A
Cited
US3144346A
Cited
US3501324A
Cited
US3679446A
Cited
US3988419A
Cited
US4128434A
Cited
US4111712A
Cited
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 |