Light sensitive invisible ink compositions and methods for using the same

An invisible ink composition comprising:

• an invisible dye comprised of a phthalocyanine fluorophore selected from the group consisting of chloroaluminum (III) phthalocyanine tetrasulfonic acid and salts thereof;
• and
• an ink vehicle comprised of water and at least one organic solvent.

An invisible ink composition comprising a phthalocyanine fluorophore selected from the group consisting of chloroaluminum (III) phthalocyanine tetrasulfonic acid and salts thereof, 1,5-pentanediol, 2-ethyl-2-hydroxymethyl-1,3-propanediol, 1,3-propanediol, at least one surfactant, and water.

An ink delivery system comprising:

• a housing comprising at least one ink retaining chamber therein, said ink retaining chamber comprising a supply of an invisible ink composition therein, said ink composition comprising an invisible dye comprised of a phthalocyanine fluorophore selected from the group consisting of chloroaluminum (III) phthalocyanine tetrasulfonic acid and salts thereof, said ink composition further comprising an ink vehicle comprised of water and at least one organic solvent;
• and
• a printhead operatively connected to said ink retaining chamber in said housing, said printhead comprising at least one ink ejector for expelling said invisible ink composition on-demand from said ink retaining chamber.

An invisible ink composition comprising a phthalocyanine fluorophore selected from the group consisting of chloroaluminum (III) phthalocyanine tetrasulfonic acid and salts thereof, an ultraviolet fluorophore comprised of benzenesulfonic acid-2,2'-(1,2-ethenediyl)bis[5-[4-bis(2-hydroxyethyl)amino]-6-[(4-sulfoph enyl)amino]-1,3,5-triazin-2yl]amino-tetrasodium salt, 1,5-pentanediol, 2-ethyl-2-hydroxymethyl-1,3-propanediol, 1,3-propanediol, at least one surfactant, and water.