WATERFAST PRIMARY COLOR DYES FOR INK JET RECORDING FLUIDS

摘要

An ink jet ink composition comprises a liquid vehicle, a dye, a co-solvent for improved waterfastness, and a branched N-hydroxyalkyl polyethyleneimine polymer substituted at about 80% of the available nitrogens. Alternatively, the Nhydroxyalkyl polyethyleneimine polymer could be replaced with an N-hydroxyalkyl diphenylguanidine substituted at about 80% of the available nitrogens. Additionally, the polyethyleneimine polymer or diphenylguanidine could be epicholorohydrin modified (1-chloro 2,3 epoxypropane) to form the corresponding N-hydroxypropyl derivative. The cosolvent preferably comprises N-methyl-pyrrolidone or N,N-dimethylformamide.