Imerys Sa

Imertech Sas

Imerys Minerals Limited

Alexandra Jakob

Didier Sy

Jean-Luc Rico

Gilles Méli

Christophe Guiton

Cédric Raboteau

Anaïs Berjeaud

This disclosure describes a process for preparing silica-coated calcium carbonate particles, involving the steps of preparing an aqueous carbonate slurry containing calcium carbonate particles, adding at least one silicate composition to the aqueous carbonate slurry to obtain a carbonate-silicate slurry, lowering a pH of the carbonate-silicate slurry by adding at least one acidic compound to obtain a pH-adjusted slurry containing the silica-coated calcium carbonate particles, and isolating the silica-coated calcium carbonate particles—in which at the adding of the acidic compound is controlled such that a final pH of the pH-adjusted slurry ranges from about 7 to about 10, and the silica-coated calcium carbonate particles include a porous coating having an average pore diameter ranging from 2 nm to 50 nm. This disclosure also describes articles and compositions containing the silica-coated calcium carbonate particles, as well as hollow silica spheres formed from the silica-coated calcium carbonate particles.

Preparation of silica-coated calcium carbonates with increased surface area and mesoporosity

Use of a porous precipitated calcium carbonate (PCC) to retain volatile organic compounds (VOCs), a method of reducing emission of VOCs from a composition, the method comprising adding a porous PCC to the composition, said compositions such as polymer compositions and methods of making said compositions.

Precipitated calcium carbonate for reducing emissions of volatile organic compounds

Use, as an opacifier, of precipitated calcium carbonate particles at least partially in the form of nano fibers or nanochain like agglomerates constituted by at least two interconnected primary particles.

Precipitated calcium carbonate particles and use thereof

Dry precipitated calcium carbonate and a slurry of precipitated calcium carbonate ('PCC') particles at least partially in the form elongated entities, especially of nanofibers or nanochain like agglomerates constituted by at least two interconnected primary particles, and preferably, with a content of scalenohedron particles, is provided having opacifying properties. The slurry may be produced on site of its use and, due to its high concentration of CaCO, may be applied directly after its manufacture.

Growing community of inventors

Arles, France

Alexandra Jakob