Cement retarder and cement retardative sheet
US5932344A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1996 |
| Grant date | Aug 3, 1999 |
| Priority date | — |
| Expiry date | Oct 7, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31794
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A cement retarder which comprises a saturated or unsaturated polyester obtained by a reaction of a polycarboxylic acid component comprising a polycarboxylic acid having 2 to 6 carbon atoms in the main chain or its derivative, and a polyol component containing a polyhydric alcohol having 2 to 4 carbon atoms or its condensate, wherein: PA1 (a) the saturated polyester has a weight average molecular weight of about 300 to about 50,000; or PA1 (b) the unsaturated polyester has a weight average molecular weight of about 500 to about 25,000; or PA1 (c) the polyhydric alcohol used to obtain the saturated or unsaturated polyester is a condensate of a C.sub.2-4 alkylene glycol; or PA1 (d) the saturated polyester is a polyester obtained by the use of a condensate of a C.sub.2-4 alkylene glycol and has a weight average molecular weight of about 300 to about 50,000; or PA1 (e) the unsaturated polyester is a polyester obtained by the use of a condensate of a C.sub.2-4 alkylene glycol and has a weight average molecular weight of about 500 to about 25,000.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.