| 摘要 |
The invention provides pigment dispersion capable of preparing aqueous ink for inkjet recording, the particle size of which is not changed after storage for a long period of time or even after being exposed to a high temperature condition, generation of streaks and unevenness are controlled, which aqueous ink is capable of forming uniform printed images excellent in light fastness. Another object is to provide aqueous ink for inkjet recording using the pigment dispersion. A pigment dispersion including vinyl polymer particles containing A and B:
A: an azo pigment represented by the following formula (1), a tautomer thereof, a salt thereof, a hydrate thereof, or a solvate thereof,
B: a vinyl polymer containing a structural unit (a) having a non-aromatic alicyclic group bonded to the polymer main chain via a linking group, and a structural unit (b) having a hydrophilic group,
wherein Q represents a nonmetallic atomic group necessary to form a 5-, 6- or 7-membered heterocyclic ring together with a carbon atom; W represents an alkoxy group, an amino group, an alkyl group or an aryl group; each of X 1 and X 2 independently represents a hydrogen atom, an alkyl group, an acyl group, an alkylsulfonyl group, or an arylsulfonyl group; R 1 represents a hydrogen atom or a substituent; R 2 represents a heterocyclic group; n represents an integer of 1 to 4, and when n is 2, formula (1) represents a dimer via Q, W. X 1 , X 2 , R 1 or R 2 , when n is 3, formula (1) represents a trimer via Q, W, X 1 , X 2 , R 1 or R 2 , and when n is 4, formula (1) represents a tetramer via Q, W, X 1 , X 2 , R 1 or R 2 . |
