Photochromic Phasenwechel-ink compositions

Phase change ink composition comprising an amorphous component, a crystalline component, a photochromic material and, optionally, a dye which is suitable for ink jet printing, including printing on coated paper substrates. The new phase change ink formulation allows the printing ink upon exposure to UV light and reversed several times the color changes, whereby an ink is provided that is suitable for use in security applications.