Process for manufacturing particles based on natural calcium carbonate and salts of acrylic acid-ethylene, suspensions and dry pigments obtained, and uses thereof

Abstract

The present invention consists in a process for preparing at least one mineral material and/or at least one pigment, comprising a calcium carbonate made both partially organophilic and partially hydrophilic, wherein the carbonate is mixed and/or ground and/or concentrated in aqueous medium in the presence of at least one salt of ethylene acrylic acid, a dispersant and/or grinding aid being introduced before and/or during this treatment step. Another subject of the invention lies in the resulting dispersions and aqueous suspensions of calcium carbonate. They may be dried, and the dry pigments obtained likewise constitute a subject of the invention. The use of these aqueous dispersions and of these dry pigments in the field of plastics, paints and paper constitutes another subject of the invention.

Description

technical field [0001] A first object of the present invention is a process for the preparation of at least one mineral and / or at least one pigment comprising natural and / or precipitated calcium carbonate, preferably natural calcium carbonate, and the method comprises the steps of: [0002] a) providing at least one mineral and / or at least one pigment comprising natural and / or precipitated calcium carbonate in dry form or in the form of an aqueous suspension and / or dispersion, [0003] b) optionally subjecting the mineral matter and / or pigment obtained from step a) to dry grinding and / or grinding in an aqueous medium, [0004] c) processing minerals and / or pigments obtained from step a) and / or step b), [0005] d) optionally drying the minerals and / or pigments obtained from steps a) and / or b) and / or c), [0006] It is characterized by: [0007] - treatment step c) corresponds to mixing and / or grinding in an aqueous medium the mineral matter and / or pigments obtained from st...

AI Technical Summary

Problems solved by technology

This emulsifier has the additional disadvantage of causing foam in the dispersion or suspension

[0023] This brings with it the first disadvantage associated with the use of stearic acid: additional steps and / or additives are required, sometimes with undesirable results during the processing process

[0046] Those skilled in the art are also familiar with the document US 5,449,402, which seeks to solve the technical problem of irreversibly combining mineral fillers with organic modifiers, which can then be used in aqueous coating compositions with improved opacity and brightness; therefore, this document absolutely does not solve the same technical problems that form the subject of this application