Acid resistant particles of an alkaline earth metal carbonate
US8324301B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2005 |
| Grant date | Dec 4, 2012 |
| Priority date | — |
| Expiry date | Sep 6, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2991
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Alkaline earth metal carbonate exhibiting a resistance to acids expressed as pH of less than 7 measured after suspending 1.0 g of the particles in a mixture made of 20 ml of toluene and 80 ml of an aqueous phase consisting of deionized water, 11.76 g/L of citric acid monohydrate, 2.57 g/L of NaCl and 0.068 mol/L of NaOH, after 35 minutes of stirring at 25° C. and at 1 000 rpm, or expressed as a moisture pick-up lower than or equal to 2 g water/kg of calcium carbonate after one week of storage at 22° C. and 50% relative humidity, or as a Differential Scanning Calorimetry (DSC) spectrum showing at least one peak between 170 and 190° C. when measured at a heating rate of 10° C./min under nitrogen atmosphere from 25 to 250° C. in open cells. Process for the preparation of said particles, compositions containing said particles and the use thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.