Ink, image recording process, ink cartridge, recording unit, ink set, crust-preventing method and image forming apparatus

摘要

An ink comprises a coloring material and an aqueous medium wherein the coloring material contains a self-dispersing type carbon black, in which self-dispersing carbon black a hydrophilic group combines with the surface of a carbon black directly or through another atomic group, and which ink contains potassium ion in an amount of 0.6 % or more of the weight of the carbon black.