| abstract |
(57) Abstract: Organic solvent-based polyester ink formulations having a fluorescent compound therein are suitable for inkjet printing applications. This ink is useful for making invisible prints / markings on the surface of various materials for identification, authentication, classification, etc. Suitable printing supports include porous and non-porous materials such as plastics, films, sheets, fabrics, papers, high gloss papers, metals, foils, plates, rubber, glass, cellophane, wood and the like. The ink formulation contains at least one organic soluble polyester having at least one near infrared fluorophore copolymerized therein dissolved in an organic solvent. Suitable organic solvents, C 3 -C 6 carbon ketone, C 3 -C 6 carbon organic esters, C 1 -C 3 carbon alcohol or a combination thereof. In a preferred embodiment, a polyester containing an infrared fluorophore copolymerized, are dissolved in a solvent consisting of C 3 -C 6 carbon ketones and C 3 -C 6 carbon alcohols. |