Described herein are printing ink compositions suitable for printing of microwavable flexible packaging. The printed black ink exhibits low microwave energy absorption, thus minimizing the risk of charring, arcing, ignition, distortion or burning during microwave heating processes. Nitrocellulose resin, a solvent, a polyurethane resin, and a carbon black pigment having at least one of an imaginary permittivity of ≤3, preferably ≤2, and a surface oxygen content of 1 wt % to 3 wt %, preferably 1.5 wt % to 2.5 wt % are among the components of the printing ink compositions. Also described is packaging suitable for exposure to microwave energy upon which the inks have been printed.