Polymer particles comprising a surfactant, obtainable by polymerization of a vinyl monomer in the presence of the surfactant, the polymer particles being classified to remove particles having a smaller particle diameter than the average particle diameter and particles having a larger particle diameter than the average particle diameter, wherein the surfactant contained in the polymer particles is a residual of the surfactant that was used for manufacturing the polymer particles, wherein the polymer particles are constituted by at least one of (meth)acrylic polymer, styrene polymer and (meth)acrylic-styrene co-polymer, wherein a volume average particle diameter, measured in accordance with the method described in the description, is in a range from not less than 1 μm to not more than 50 μm, wherein a coefficient of variation in a volume-based particle diameter distribution, measured in accordance with the method described in the description, is in a range from more than 15.0% to not more than 25.0%, wherein a value obtained by dividing a coefficient of variation in a number-based particle diameter distribution, measured in accordance with the method described in the description, by the coefficient of variation in the volume-based particle diameter distribution is in a range of 1.0 to 3.0, and wherein, when 15.0 g of water is added to 5.0 g of the polymer particles so as to disperse the polymer particles in the water by performing a dispersion treatment for 60 minutes using an ultrasonic cleaner, and furthermore when an obtained dispersion liquid is put into a centrifuge tube with an inside diameter of 24 mm so as to be centrifuged, by a centrifugal separator, under conditions that K factor is 6943 and a rotating time is 30 minutes to recover a supernatant, a concentration of non-volatile components in the obtained supernatant is less than 3.5 wt. %. wherein the surfactant contained in the polymer particles is a residual of the surfactant that was used for manufacturing the polymer particles, wherein the polymer particles are constituted by at least one of (meth)acrylic polymer, styrene polymer and (meth)acrylic-styrene co-polymer, wherein a volume average particle diameter, measured in accordance with the method described in the description, is in a range from not less than 1 μm to not more than 50 μm, wherein a coefficient of variation in a volume-based particle diameter distribution, measured in accordance with the method described in the description, is in a range from more than 15.0% to not more than 25.0%, wherein a value obtained by dividing a coefficient of variation in a number-based particle diameter distribution, measured in accordance with the method described in the description, by the coefficient of variation in the volume-based particle diameter distribution is in a range of 1.0 to 3.0, and wherein, when 15.0 g of water is added to 5.0 g of the polymer particles so as to disperse the polymer particles in the water by performing a dispersion treatment for 60 minutes using an ultrasonic cleaner, and furthermore when an obtained dispersion liquid is put into a centrifuge tube with an inside diameter of 24 mm so as to be centrifuged, by a centrifugal separator, under conditions that K factor is 6943 and a rotating time is 30 minutes to recover a supernatant, a concentration of non-volatile components in the obtained supernatant is less than 3.5 wt. %. <EOS>