Inventors: Krutak, James J.; Cushman, Michael R.; Coates, Clarence A.; Parham, William W.; Weaver, Max A.; Patonay, Gabor;
Assignee: Eastman Chemical Company (Kingsport, TN)
Primary Examiner: Shah; Mukund J.
Assistant Examiner: Sripada; Pavanaram K.
Attorney, Agent or Firm: Harding; Karen A., Graves, Jr.; Bernard J., Heath, Jr.; William P.
Provided are new compounds useful as near infrared fluorophoric markers. In the practice of this invention a method is also provided for tagging thermoplastic containers using near infrared fluorescing compounds or copolymerized residues readily capable of detection. The new compounds are phthalocyanine and naphthalocyanine derivatives which are covalently bonded to substituted silicon and aluminum compounds. The methods, compositions, and compounds described herein thus provide a total system useful for marking, for identification purposes, the various classes of thermoplastic wastes, so that they can be identified, sorted, and subsequently recycled. |