| 摘要 |
PROBLEM TO BE SOLVED: To obtain an ink composition not requiring a specific apparatus, applicable to a printer, etc., facilitating the follow-up check of forged copy printed material by making the composition include a colorant, water, a diazonium salt compound and a coupler to be reacted with the diazonium salt compound and to be colored. SOLUTION: This ink composition comprises at least (A) preferably 0.5-5 wt.% (based on the total amount of the ink) of a colorant such as a water-soluble dye and/or pigment, (B) water, (C) preferably 0.02-5 wt.% of a diazonium salt compound such as 2,5-dibutoxy-4-morpholinobenzenediazonium and (D) preferably 0.02-10 wt.% of a coupler to be reacted with the component C and colored such as resorcinol. The ink composition is colored by heating at >=80 deg.C after recording on a recording medium or colored by pressure under >=10 kg/cm2 after recording on a recording medium. Preferably ink-jet recording is carried out by using the ink composition. |
