Curable printing ink compositions include a visible light transparent, UV-curable binder composition and a visible light transparent, and infrared light absorbing inorganic composition. The infrared light absorbing inorganic composition can include infrared absorbing nanoparticles. The ink compositions are capable of flexographic printing at room temperature to a thickness of at least 1.0 micrometer. The cured ink composition has an infrared absorbance of at least 50%. The ink compositions can be printed in patterns of geometric features and cured to form articles.