Patent EA-005272-B1 (EA)
Title: Liquid concentrate of mineral fillers containing grafted polymers and their use for preparing paints in aqueous and/or organic medium
Inventor: LEGRAND PIERRE
IPC: C09D151/00
Filed: 2002-03-29
Abstract: 1. Liquid concentrate of colourless mineral fillers which can be used to manufacture paints containing an aqueous or organic solvent of said mineral fillers and a grafted copolymer containing at least three sequences of different chemical nature, among which at least one anchoring sequence able to be absorbed on solid particles consisting of said mineral fillers, at least one sequence of a hydrophobic nature and at least one sequence of a hydrophilic nature, characterized in that it comprises a dry extract of said mineral fillers of 65% or more by weight of said liquid concentrate, and said copolymer is made up of: 1) 5 to 40 weight %, preferably 15 to 35 weight % and further preferably 20 to 30% weight % of said anchoring sequence(s) consisting of a linear copolymer formed from at least two separate monomer units containing: a) a first monomer unit comprising at least one basic nitrogenous group preferably chosen from among vinyl pyridine or preferably from aminoalkyl(meth)acrylates having following formula (1): in which n is a whole number from 0 to 6; R1 is a hydrogen or a (C1-C4) alkyl radical; R2 and R3 are identical or different and each represent a hydrogen or an a (C1-C4) alkyl radical, and b) said second monomer of the anchoring sequence consists of a monomer having following formula II: in which: R4, R5, R6 are identical or different and each represent a hydrogen or a C1-C4 alkyl radical, preferably a hydrogen, R7 represents an aromatic group, in particular an optionally substituted phenyl group, a second unsaturated ethylene monomer unit comprising an aromatic group, preferably a phenyl, which can be unsubstituted or substituted, the weight content of said first monomer units relative to said second monomer units being 40 to 60%, preferably approximately 50%., 2) 25 to 90 weight %, preferably 40 to 80 weight %, further preferably 50 to 70 weight % of said hydrophobic sequence(s) containing organosoluble polymers, and 3) 5 to 70 weight %, preferably 15 to 30 weight %, further preferably 10 to 20 weight % of hydrophilic sequences, containing water-soluble polymers. 2. Liquid concentrate according to claim 1, characterized in that in said anchoring sequence, said first monomer is the monomer of 2-dimethylaminoethyl methacrylate and said second monomer is styrene. 3. Liquid concentrate according to any of claims 1 or 2, characterized in that said hydrophobic sequence is formed of a hydrocarbon chain containing -COOR10- groups in which R10 is a C1-C10 alkyl, and preferably also OH groups. 4. Liquid concentrate according to claim 3, characterized in that said hydrophobic sequence is obtained from a macromonomer having following formula III: in which: R4, R5, R6 are identical or different and each represent a hydrogen or a C1-C4 alkyl radical, preferably a hydrogen, R8 is formed by a polymer whose monomer units contain -COOR10 groups, in which R10 is a C1-C10 alkyl and preferably a C4-C8 alkyl. 5. Liquid concentrate according to claim 4, characterized in that in said hydrophobic sequence of formula III, R8 is formed from monomer units having following formula IV: in which: R4, R5, R6 are identical or different and each represent a hydrogen or a C1-C4 alkyl radical, preferably a hydrogen, R'8 represents -COOR10 groups, in which R is a C1-C10 alkyl and preferably a C4-C8 alkyl. 6. Liquid concentrate according to claim 5, characterized in that in said formula IV, R'8 is an ethylhexyl methacrylate. 7. Liquid concentrate according to any of claims 1 to 6, characterized in that said hydrophilic sequence is formed by a hydrocarbon chain containing groups chosen from among -O, -OH, -COOH. 8. Liquid concentrate according to any of claims 1 to 7, characterized in that said hydrophilic sequence is obtained from a macromonomer having following formula V: in which: R4, R5, R6 are identical or different and each represent a hydrogen or a C1-C4 alkyl radical, preferably a hydrogen, R9 is a sequence of hydrophilic nature formed of a polymer whose monomer units contain groups chosen from among -O-, -OH, -COOH. 9. Liquid concentrate according to claim 8, characterized in that in formula (V), R9 is polyethylene glycol. 10. Liquid concentrate according to claim 9, characterized in that the hydrophilic sequence consists of a macromonomer of polyethylene glycol methacrylate having a molecular weight of 500 or more. 11. Liquid concentrate according to any of claims 1 to 10, characterized in that the molecular weight of the grafted copolymer lies between 5000 and 25000, preferably between 10000 and 20000. 12. Liquid concentrate according to any of claims 1 to 11, characterized in that said colourless mineral fillers which can be used for manufacturing paints are chosen from among fillers of carbonate, silicate, silica and sulfate type. 13. Liquid concentrate of mineral fillers according to any of claims 1 to 12, characterized in that it contains a dry extract of mineral fillers of 70% or more. 14. Liquid concentrate of mineral fillers according to any of claims 1 to 13, characterized in that the dry extract weight content of said grafted copolymers is 10 to 15% by weight of said liquid concentrate. 15. Method for preparing paints, characterized in that a liquid concentrate of mineral fillers is used according to any of claims 1 to 13 and that it is mixed with the other paint constituents.