RECORDING FLUID AND RECORDING PROCESS

摘要

PROBLEM TO BE SOLVED: To obtain a recording fluid which can give recorded images having vivid colors and reduced in blotting at the boundary of colors and has good stability in long-term storage by including a water-soluble colorant specified from a spectrum pattern of proton nuclear magnetic resonance(NMR) at 400 MHz and an aqueous medium. SOLUTION: A water-soluble colorant having at least one peak having a half-width of 0.1 ppm or above in a spectrum pattern of NMR is selected. The colorant has no particular limitations on its skeletal structure and may be one selected among azoic, triphenylmethane and fused polycyclic compounds, etc., and it is particularly desirably one having 1-4 azo groups. Further, when the hue of the colorant is Magenta, Yellow or Cyan, the image quality can be further improved. To dissolve the colorant in an aqueous medium, the water- soluble colorant is dissolved in highly pure water, the solution is optionally decontaminated by e.g. treatment with an ion exchange resin, a water-soluble organic solvent such as ethylene glycol is added to the solution, and the resultant solution is passed through a precision filter membrane having a pore diameter of 1-0.2μm. The colorant concentration is 0.5-7 wt.%.