Aqueous polymer preparations containing pigments

A pigmented aqueous formulation which is essentially free from organic solvents, comprising:

• i) at least one polymer A in the form of polymer particles in disperse distribution, said particles comprising
• from 90 to 99% by weight, based on the overall weight of the polymer A, of a water-insoluble polymer 1 having a glass transition temperature Tg1 in the range of −50 to +40° C., built up from ethylenically unsaturated monomers M1, and
• from 1 to 10% by weight, based on the overall weight of the polymer A, of one or more water-insoluble polymers i having a glass transition temperature Tgi of more than 30° C., built up from ethylenically unsaturated monomers Mi,
• wherein, for all polymers i, the difference Tgi−Tg1 is >10° K,
• ii) at least one pigment and, optionally, one or more extenders, wherein the polymer A is obtained by a multistage free-radical emulsion polymerization process in an aqueous polymerization medium, comprising the successive stages of:
• a) preparing a polymer 1 by polymerizing the monomers 1 in a first polymerization stage,
• b) preparing a first polymer i by polymerizing a first batch of the monomers Mi in the presence of the polymer 1 in a second polymerization stage,
• c) optionally, preparing further polymers i by polymerizing further monomers Mi in successive polymerization stages i in the presence of the polymer of the respective preceding polymerization stage,
• the polymerization of the monomers M1 being essentially at an end before the addition of the monomers Mi is begun in the second polymerization stage, and the addition of the monomers Mi in the second and any subsequent polymerization stages taking place such that, during the addition of the monomers Mi, the polymerization conversion Ui of the monomers Mi to be polymerized in the respective preceding polymerization stage at no point exceeds 50 mol %.