Patent ID: 6245832
Filing Date: 2001-06-12
Classification: C09D

Abstract:
An ink for ink jet recording comprising water, a water-soluble organic solvent, a pigment and a dispersant, wherein the dispersant has a hydrophilic moiety and a hydrophobic moiety and comprises a copolymer obtained by copolymerizing from 40 to 80 mol % of a monomer having an .alpha., .beta.-ethylenically unsaturated group constituting the hydrophilic moiety and from 20 to 60 mol % of a styrene monomer constituting the hydrophobic moiety, the copolymer has a weight average molecular weight Mw of from 3,000 to 15,000 and assuming that the number average molecular weight is Mn, the Mw/Mn is from 1 to 2.5, wherein the change in viscosity of the ink after storage at 60.degree. C. for 100 hours is 0.3 mPa.multidot.s or less at a shear rate of 1,400 s.sup.-1.