Crosslinked core/shell polymer particles

A process for producing crosslinked core/shell polymer particles containing a pigment, wherein a weight ratio of the pigment to the pigment-containing crosslinked polymer particles [(weight of the pigment/weight of the pigment-containing crosslinked polymer particles)×100] is from 25 to 75, comprising the following steps (1) to (3):

• Step (1):
• mixing pigment-containing polymer particles, a crosslinkable monomer containing at least two reactive unsaturated groups in a molecule thereof, and a hydrophobic monomer with each other to incorporate at least a part of the crosslinkable monomer and the hydrophobic monomer into the pigment-containing polymer particles;
• Step (2):
• polymerizing the crosslinkable monomer with the hydrophobic monomer to obtain polymer particles;
• and
• Step (3):
• reacting the polymer particles which are obtained in the step (2), with a crosslinking agent containing at least two epoxy groups in a molecule thereof.