Patent ID: 8633278

Claim:
A process for preparing a water-in-oil polymer dispersion, comprising radically polymerizing a radically polymerizable cationic monomer, and optionally one or more radically polymerizable, ethylenically unsaturated co-monomers, in a water-in-oil monomer dispersion comprising: water; an oily substance; a water-in-oil emulsifier; a first cationic polymer obtained from a monomer mixture comprising a cationic (alk)acrylic acid monomer and a radically polymerizable ethylenically unsaturated non-ionic monomer, wherein a content of cationic monomers is at most 95 wt.-%, based on a total weight of monomers; the radically polymerizable cationic monomer, wherein the radical polymerization of the cationic monomer takes place in the presence of the first cationic polymer; and optionally, a radically polymerizable, ethylenically unsaturated co-monomer, wherein the radical polymerization polymerizes the radically polymerizable cationic monomer to form a second cationic polymer; and wherein the water-in-oil dispersion comprises water, the oily substance, the emulsifier and the first and second cationic polymers.