Three-dimensional printing with coalescing agent

A three-dimensional printing kit, comprising:

• a polymer build material including from about 80 wt % to 100 wt % polymeric particles;
• and
• a coalescing agent including an aqueous liquid vehicle and a coalescing solvent that depresses a melting point of the polymeric particles when contacted therewith,
• wherein the three-dimensional printing kit excludes a fusing agent containing a radiation absorber.

A system for three-dimensional printing, comprising:

• a polymer build material including from about 80 wt % to 100 wt % polymeric particles;
• a coalescing agent including an aqueous liquid vehicle and a coalescing solvent operable to depress a melting point of the polymeric particles;
• a printhead fluidly coupled to or fluidly coupleable to the coalescing agent to selectively and iteratively eject the coalescing agent onto successive placed individual layers of the polymer build material, wherein the coalescing agent depresses a melting point of the polymeric particles;
• and
• a radiant heat source positioned or positionable to expose the individual layers of the polymer build material to radiation energy to selectively fuse the polymeric particles in contact with the coalescing solvent to iteratively form a three-dimensional object.