WATER-SOLUBLE NEAR-INFRARED ABSORBING COLORING MATTERS AND AQUEOUS INKS CONTAINING SAME

摘要

Coloring matters represented by general formula (1) or salts thereof are simply provided at a low cost as water-soluble coloring matters which exhibit absorption in the near-infrared region.  Further, aqueous ink compositions which contain the coloring matters and have excellent storage stability are also provided.  In general formula (1), Nc is optionally substituted naphthalocyanine; M is a metal oxide or the like; R1 and R2 are each independently hydrogen or the like; A is a crosslinking group; X and Y are each independently substituted arylamino or the like; k is more than 0 but up to 12 (on average); p is 0 to less than 12; the sum of k and p is more than 0 but up to 12; and any two or the three of R1, R2 and A may be united to form a ring.