Patent ID: 8663734

Claim:
A process for producing water-absorbing polymer particles by polymerizing a monomer solution or suspension comprising a) at least one ethylenically unsaturated acid-bearing monomer which may be at least partly neutralized, b) at least one crosslinker, c) optionally one or more ethylenically and/or allylically unsaturated monomers copolymerizable with the monomers specified under a), and d) optionally one or more water-soluble polymers, followed by drying, grinding, and classifying the polymerized material into water-absorbing polymer particles, and then spraying a liquid onto the water-absorbing polymer particles using at least one two-substance spray nozzle in a horizontal mixer with moving mixing tools, wherein the spray nozzle is immersed into a product bed of the water-absorbing polymer particles and the liquid is sprayed below the product bed surface, and horizontal mixer moves with a speed which corresponds to a Froude number of from 0.1 to 0.7.