Preparations of suspensions of ground particulate material
US6003795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1998 |
| Grant date | Dec 21, 1999 |
| Priority date | — |
| Expiry date | Jul 14, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/22
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
There is disclosed a method of preparing a concentrated aqueous suspension of a finely ground particulate material by a multistage grinding process in which an aqueous suspension of the particulate material is passed to and treated by grinding in each of a series of grinding stages, wherein a water soluble polycarboxylate dispersing agent for the particulate material is added to the suspension at each of a plurality of dispersion agent addition sites or stages. The invention is characterised in that the aqueous suspension when treated by grinding in at least one of the grinding stages has a pH on the inclusive range 8.5 to 9.8. Using the method described, suspensions can be prepared which are rheologically stable with time, and which contain a relatively high proportion by weight of a finely divided pigment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.