Abstract: An ink jet ink contains a polyurethane polymer and a pigment. The polyurethane polymer has units derived from a polyisocyanate, a polyether polyol having no acid group, and a diol having an acid group. The pigment is dispersed using a polymer other than the polyurethane polymer. The ratio of the percentage of the urethane bond in the polyurethane polymer to the percentage of the urea bond in the polyurethane polymer is 85.0/15.0 or more and 98.5/1.5 or less.

Abstract: To provide an ink jet ink that produces an image having high optical density, scratch resistance, and highlighter resistance, has excellent ink ejection stability, and can reduce image deflection caused by face wetting. The ink jet ink contains a polyurethane polymer and a self-dispersing pigment. The polyurethane polymer has units derived from a polyisocyanate, a polyol having no acid group, and a diol having an acid group. The molar ratio of the percentage of the urethane bond in the polyurethane polymer to the percentage of the urea bond in the polyurethane polymer is 85.0/15.0 or more and 100.0/0 or less.

Abstract: An ink used for an inkjet recording method for discharging the ink from a recording head by an action of thermal energy contains self-dispersing carbon black, a polyurethane polymer having an acid value of 40 mg KOH/g or more, and an acryl polymer having an acid value of 100 mg KOH/g or more and 200 mg KOH/g or less.

Abstract: The invention provides an ink containing a polyurethane polymer which has units respectively derived from a polyisocyanate, a polyether polyol having no acid group and a diol having an acid group and has an acid value of 40 mg KOH/g or more and 140 mg KOH/g or less, a carbon black and at least one antioxidant selected from compounds represented by the general formulae (1) to (3).

Abstract: The invention provides an ink containing a self-dispersion pigment in which a phosphonic acid group is bonded directly or through another atomic group to the surface thereof and a polyurethane polymer, wherein the surface charge amount of the self-dispersion pigment is 0.25 mmol/g or more and 0.42 mmol/g or less, and the polyurethane polymer has units respectively derived from a polyisocyanate, a polyether polyol having no acid group and a diol having an acid group.

Abstract: An ink used for an inkjet recording method for discharging the ink from a recording head by an action of thermal energy contains self-dispersing carbon black, a polyurethane polymer having an acid value of 40 mg KOH/g or more, and polyethylene glycol.

Abstract: An ink jet ink contains a polyurethane polymer and a pigment. The polyurethane polymer has units derived from a polyisocyanate, a polyether polyol having no acid group, and a diol having an acid group. The pigment is dispersed using a polymer other than the polyurethane polymer. The ratio of the percentage of the urethane bond in the polyurethane polymer to the percentage of the urea bond in the polyurethane polymer is 85.0/15.0 or more and 98.5/1.5 or less.

Abstract: An ink jet ink contains a polyurethane polymer and a pigment. The polyurethane polymer has units derived from a polyisocyanate, a polyether polyol having no acid group, and a diol having an acid group. The pigment is dispersed using a polymer other than the polyurethane polymer. The molar ratio of the percentage of the urethane bond in the polyurethane polymer to the percentage of the urea bond in the polyurethane polymer is 85.0/15.0 or more and 100.0/0 or less.