Naphthalocyanine compounds
AssigneeYamamoto Kagaku Gosei Co., Ltd.
InventorTsunehito Eda
Life of this patent
Estimating the term…
Abstract
Naphthalocyanine compounds represented by the general formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, are each a straight chain or branched chain alkyl group of 5 to 12 carbon atoms and M is a metal selected from the group consisting of Cu, Ni, Mg, Pb, Pd, V, Co, Nb, Al, Sn, In, Fe and Ge, or its oxide, chloride or bromide, are bluish green or green crystals and are superior in absorption of near infrared rays of 750 to 850 nm, highly resistant to light, heat, acids and alkalis, soluble in organic acids, liquid crystals and resins, and accordingly are very useful as a dyestuff capable of absorbing near infrared rays.
Claims18
A naphthalocyanine compound represented by the general formula ##STR8## characterized in that R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, are each a straight or branched alkyl group of 5 to 12 carbon atoms and M is a metal selected from the group consisting of Cu, Ni, Mg, Pb, Pd, V, Co, Nb, Al, Sn, In, Fe and Ge or its oxide, chloride or bromide.
Dependencies are inferred from the claim text.