Thioheterocyclic near-infrared dyes

Disclosed is a novel near-infrared absorbing dye of formula: wherein X1, X2 independently represents -CR8R9-, -S-, -Se-, -NR10-, -CH=CH- or -O-; n is an integer of 2 or 3; R1 and R2 independently represent alkyl of 1 to 10 carbons or substituted alkyl of 1 to 10 carbons; R3 represents a ring chosen...

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