Stabilised concentrated mineral suspension
AssigneeCoatex
InventorsChristian JACQUEMET, Laurie PARRENIN, Morgane LE NEINDRE
Life of this patent
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Abstract
An aqueous suspension of a mineral material, for example calcium carbonate, is described. The aqueous suspension is prepared by wet grinding step followed by a concentration step in the presence of at least one rheological agent R comprising phosphoric acid and an α-sulfonated polymer P which is completely or partially neutralised by a monovalent ion. A rheological agent R and the use of this mineral suspension for preparing a mass filler for paper, for preparing a paper coating slip, or for preparing a coating composition, for example a paint composition, is also described.
Claims18
An aqueous suspension S of particles comprising at least one mineral material M prepared by a method comprising, in order:
- grinding in water an aqueous suspension Sd of at least one particulate mineral material M at a concentration ranging from 10% by weight to 60% by weight;
- and
- concentrating the ground suspension Sd to a concentration ranging from 65% by weight to 80% by weight, by a treatment chosen among mechanical treatment, heat treatment, and combinations thereof, in the presence of at least one rheological agent R comprising phosphoric acid and at least one α-sulphonated polymer P prepared in water and in the absence of any phosphorus compound, by a polymerisation reaction of at least one monomer A chosen among acrylic acid, methacrylic acid, an acrylic acid salt, a methacrylic acid salt, and combinations thereof, in the presence of at least one initiator compound and of at least one sulphur compound T comprising sulphur in oxidation state IV, and completely or partially neutralised by at least one monovalent ion.
A rheological agent R comprising phosphoric acid and at least one α-sulphonated polymer P prepared in water and in the absence of any phosphorus compound, by a polymerisation reaction of at least one monomer A chosen among acrylic acid, methacrylic acid, an acrylic acid salt, a methacrylic acid salt, and combinations thereof, in the presence of at least one initiator compound and of at least one sulphur compound T comprising sulphur in oxidation state IV, and completely or partially neutralised by at least one monovalent ion, and optionally a compound B chosen among a sulpho-carboxylic acid, a sulpho-carboxylic acid salt, and combinations thereof.
A method for controlling the rheology of an aqueous suspension S of particles comprising at least one mineral material M prepared by a method comprising, in order:
- grinding in water an aqueous suspension Sd of at least one particulate mineral material M at a concentration ranging from 10% by weight to 60% by weight;
- and
- concentrating the ground suspension Sd to a concentration ranging from 65% by weight to 80% by weight, by a treatment chosen among mechanical treatment, heat treatment, and combinations thereof, comprising the use during concentration of at least one rheological agent R comprising phosphoric acid and at least one α-sulphonated polymer P prepared in water and in the absence of any phosphorus compound, by a polymerisation reaction of at least one monomer A chosen among acrylic acid, methacrylic acid, an acrylic acid salt, a methacrylic acid salt, and combinations thereof, in the presence of at least one initiator compound and of at least one sulphur compound T comprising sulphur in oxidation state IV, and completely or partially neutralised by at least one monovalent ion.
Dependencies are inferred from the claim text.