Forming the pigment of the ink jet ink in order refinement manner of the giant molecule color development group and the production mannered null anion

摘要

PROBLEM TO BE SOLVED: To provide a method for purifying a macromolecular chromophore(MMC) of a pigment used for an ink jet ink. ;SOLUTION: By the surface treatment of a pigment, anionic or cationic functional groups are covalently bonded to the surface, and these functional groups have unfavorable counter ions adversely affecting an ink having MMC. In this method, an aq. soln. of MMC is prepd.; a liquid of desired counter ions is added to the aq. soln.; membrane filtration is applied; and the addition of the liquid and the filtration are repeated. Thus, crusting or kogation is reduced and the reliability, such as long-term stability, of ink is improved.;COPYRIGHT: (C)1999,JPO