The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 19, 2002
Filed:
Sep. 21, 2000
William D. Ramsden, Afton, MN (US);
Louis F. Valente, Fairport, NY (US);
Lori S. Bernard, Hudson, WI (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A method to make squaraine dyes involves the reaction of 1,8-diaminonaphthalene with 1,3-dihydroxyacetone dimer in a first reaction mixture comprising the appropriate solvents to prepare a first intermediate. This first intermediate is then reacted with an organic acylating agent in the presence of a suitable solvent to form a second intermediate. Lastly, after isolation, the second intermediate is reacted with squaric acid in a particular hydroxylic solvent/nonpolar solvent mixture that dissolves squaric acid and forms a ternary azeotrope with water and the water is at least partially removed. The resulting dyes have the following general structure wherein R is an organic radical derived from the organic acylating agent.