Patent ID: 8221587
Filing Date: 2012-07-17
Classification: C01P,C09C,D21F,D21H

Abstract:
1. A method for manufacturing a sheet of paper from a papermaking pulp, wherein the papermaking pulp is derived from mixing: a natural fiber, a synthetic fiber, or a mixture thereof; water; and an aqueous suspension or dispersion comprising an agent for slowing the penetration of a paper coating into the sheet of paper, wherein the agent comprises a mineral material and a water-soluble copolymer, wherein the water-soluble copolymer comprises: a) at least one ethylenically-unsaturated anionic monomer in an acid or salt form selected from the group consisting of: an ethylenically-unsaturated anionic monomer having a monocarboxylic functional group in acid or salt form and selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, cinnamic acid, a C an ethylenically-unsaturated monomer having a dicarboxylic functional group in acid or salt form and selected from the group consisting of itaconic acid, maleic acid, fumaric acid, mesaconic acid, citraconic acid, and maleic anhydride; an ethylenically-unsaturated monomer having a sulfonic functional group in acid or salt form and selected from the group consisting of acrylamido-2-methyl-2-propane-sulfonic acid, sodium methallylsulfonate, sulfonic vinyl acid, and sulfonic styrene acid; an ethylenically-unsaturated monomer having a phosphoric functional group in acid or salt form and selected from the group consisting of phosphoric vinyl acid, ethylene glycol methacrylate phosphate, propylene glycol methacrylate phosphate, ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate, and ethoxylates thereof; an ethylenically-unsaturated monomer of phosphonic vinyl acid having a phosphonic functional group in acid or salt form; and mixtures thereof; and b) at least one ethylenically-unsaturated oxyalkylated monomer terminated by a hydrophobic chain, represented by the following general formula (I): wherein: m and p represent a number of alkylene oxide units less than or equal to 100, n represents a number of ethylene oxide units less than or equal to 100, and q is a number at least equal to 1, with 0≦q(n+m+p)≦100, R R R represents a polymerizable unsaturated radical selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, crotonic acid, an ester of vinylphthalic acid, an acrylurethane, a methacrylurethane, an α,α′-dimethyl-m-isopropenyl-benzylurethane, and an allylurethane, and R′ represents a hydrophobic radical which is a branched alkyl, alkylaryl, arylalkyl, or aryl group having 16 to 20 carbon atoms with two branches having at least 6 carbon atoms, or mixtures of these radicals.