| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an ultrafinaly particulate org. pigment color ink which is excellent in storage stability, does not cause head clogging, and is excellent in print equality and lightfastness by compounding an ultrafinaly particulate org. chromatic color pigment, a specific amphipathic compd., and a water-base solvent. SOLUTION: This ink contains an org, pigment an amphipathic compd. both in an amt. of 0.1-20wt.% of the compsn. and has a viscosity of 10cp or lower at 25 deg.C. The pigment may be a known org. pigment (e.g. a cyan pigment), pref. has a particle size of 50μm or lower, and pref. moves 10cm or lower when kept under an acceleration of 10,000G for 1hr. The amphipathic compd. has a hydrophilic part, a polyethylene oxide part, having a mol.wt. (x) of 300 or higher but not higher than 3,500 and a hydrophobic part, an alkyl group and/or an arom, ring, having a mol.wt. (y) of 100 or higher but not higher than 500 provided x/y is 1 or higher but not higher than 20. An example of the water- base solvent is a mixture of ion-exchanged water and acetylenic glycol.</p> |
