Multi-detectable ink compositions and method of use

The method of processing and distinguishing articles comprising the steps of

• A. marking the articles with an ink,
• 1. said ink having a first coloration in ordinary mixed light, but which fluoresces within a predetermined wavelength range when irradiated, said fluorescent color being different than the mixed light color of said ink,
• a. said ink containing
• i. 2 to 25% by weight of at least one fluorescent pigment,
• ii. 0.3 to 10% of at least one non-fluorescent pigment,
• iii. 0.25 to 5% gellant, and
• iiii. 0 to 1% antioxidant
• iiiii. all being in an ink vehicle essentially comprising the remainder of said ink;
• then
• B. processing the articles by detection means comprising a detector responsive to at least the fluorescent wavelength of said ink,
• whereby said articles may be processed by a machine having at least fluorescent detection means covering the range of fluorescent wavelength of said ink and said articles may be further optically processed by differentiation of the mixed light color of said inks.