INK, INK-JET RECORDING PROCESS, RECORDING UNIT, INK CARTRIDGE, AND INK-JET RECORDER

摘要

PROBLEM TO BE SOLVED: To obtain an ink which, even when used in recording a print on plain paper, can form a sufficiently light-resistant high-grade print thereon without any adverse effect on the development of the color of the obtained print by adding a near-infrared-absorbing compound to a water-base ink comprising a colorant and water. ;SOLUTION: At least one of near-infrared-absorbing compounds represented by formulae I and II is added to a water-base ink. In the formulae, R1 to R8 are each H, a 1-8C substituted or unsubstituted alkyl, a substituted or unsubstituted alkenyl, a substituted or unsubstituted aralkyl, or a substituted or unsubstituted alkynyl, provided that a combination of R1 and R2, R3 and R4, R5 and R6, or R7 and R8 may form, together with the N atom, a substituted or unsubstituted five-membered ring, a substituted or unsubstituted six-membered ring, or a substituted or unsubstituted seven-membered ring; (n) is 1 or 2; and X- is an anion. The amount of the near-infrared-absorbing compound added is desirably 5-100 wt.% base on the amount of the colorant added.;COPYRIGHT: (C)2001,JPO