PURPOSE: To provide the subject ink containing a reactional product of an amine compound and a polyester in addition to carbon black having a specific particle size and a lubricant, causing little abrasion of the printing wire and giving a printed letter having sufficiently high visual density.
CONSTITUTION: The objective composition contains (A) a carbon black having an average primary particle diameter of ≤20mμ (preferably ≤15mμ), (B) a lubricant and (C) a reactional product produced by the reaction of (i) an amine compound of formula I or formula III [R1, R2, R4 and R5 are 2-4C alkylene; R3 is 1-4C alkyl; (n) is integer of 1-4 (when (n) is integer of 2 or more, plural R4 groups may have different carbon numbers)] with (ii) a polyester having free carboxyl group.
ITO KAZUNORI
NAKADA ATSUSHI
