Global Patent Index - EP 1242329 A1

EP 1242329 A1 2002-09-25 - GYPSUM-RICH PORTLAND CEMENT

Title (en)

GYPSUM-RICH PORTLAND CEMENT

Title (de)

GIPSREICHER PORTLANDZEMENT

Title (fr)

CIMENT PORTLAND RICHE EN GYPSE

Publication

EP 1242329 A1 (EN)

Application

EP 00960020 A

Priority

  • US 0024621 W
  • US 39432299 A
  • US 53821700 A

Abstract (en)

[origin: WO0119751A1] The present invention is of a cementitious composition containing Ordinary Portland Cement (OPC), calcined gypsum, a source of amorphous silica and a source of amorphous alumina. The ratio of calcium sulfate hemihydrate to OPC is 0.7:1.0 to 1.8:1.0, the ratio of amorphous silica and amorphous alumina to OPC is 0.26:1.0 to 0.4:1.0, and the ratio of amorphous alumina to amorphous silica is 0.3:1.0 to 1.5:1.0. The cementitious composition, by itself and mixed with aggregates, is fast-setting and exhibits good early compressive strength and very high compressive strength after hydration. Despite the high content of calcium sulfate relative to prior art OPC formulations, the cementitious composition according to the present invention is essentially waterproof and exhibits excellent strength characteristics, even after 2 years under water. The use of calcined gypsum in place of alumina cement or even OPC is of great economic advantage, and in addition, provides the cementitious composition with quick-setting characteristics. Soluble anhydrite can replace some or all of the calcined gypsum.

IPC 1-7 (main, further and additional classification)

C04B 11/30; C04B 14/10; C04B 14/36

IPC 8 full level (invention and additional information)

C04B 11/30 (2006.01); C04B 18/14 (2006.01); C04B 22/06 (2006.01); C04B 22/08 (2006.01); C04B 28/04 (2006.01); C04B 28/14 (2006.01)

CPC (invention and additional information)

C04B 28/145 (2013.01); Y02W 30/92 (2015.05); Y02W 30/94 (2015.05)

Combination set (CPC)

  1. C04B 28/145 + C04B 7/02 + C04B 18/025 + C04B 18/101
  2. C04B 28/145 + C04B 7/02 + C04B 14/106 + C04B 18/141 + C04B 20/0048

Citation (search report)

See references of WO 0119751A1

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

EPO simple patent family

WO 0119751 A1 20010322; WO 0119751 A9 20021121; AU 7124500 A 20010417; AU 766242 B2 20031009; CA 2384747 A1 20010322; EP 1242329 A1 20020925; IL 143996 D0 20020421; JP 2003509322 A 20030311; MX PA02002631 A 20031014; NZ 517474 A 20030829

INPADOC legal status


2006-09-27 [18D] APPLICATION DEEMED TO BE WITHDRAWN

- Effective date: 20060401

2002-09-25 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20020325

2002-09-25 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

2002-09-25 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO:

- Free text: AL PAYMENT 20020325;LT PAYMENT 20020325;LV PAYMENT 20020325;MK PAYMENT 20020325;RO PAYMENT 20020325;SI PAYMENT 20020325