THREE-DIMENSIONAL PRINTING

Described herein are kits, methods, and systems for printing metal three-dimensional objects. In an example, described is a kit for three-dimensional printing comprising: powdered metal build material; and a binding fluid comprising a liquid vehicle, metal or metal precursor particles, and latex polymer particles dispersed in the liquid vehicle, wherein the latex polymer particles have an average particle size of from about 10 nm to about 300 nm, and wherein the metal or metal precursor particles comprise metal nanoparticles, metal oxide nanoparticles, metal oxide nanoparticles and a reducing agent, or combinations thereof.