| abstract |
"PIGMENT DISPERSANT, PROCESS FOR DISPERSING A PIGMENT IN A WATERFUL MEDIA, PIGMENT DISPERSION, AND, WATER INK". a pigment dispersion is provided which includes 80-97% by weight, based on the weight of the pigment dispersant, of a first polymer which comprises as copolymerized units of 15-75% by weight, based on the weight of the first polymer, of an ethylenically unsaturated carboxylic acid function monomer, the polymer having a MW of 4000 to 16000, and the polymer having a Tg greater than 70 <198> C; and 3-20% by weight, based on the weight of the pigment dispersant, of a second poly block polymer (ethylene oxide / propylene oxide) having a MW of 3000 to 20000 and an HLB value of 16 to 32. The invention further relates to a process for dispersing a pigment in an aqueous medium using the pigment dispersant, an aqueous pigment dispersion that includes the pigment dispersant, and an aqueous ink that includes the pigment dispersion. |