An ink used in an ink-jet recording process in which ink droplets are ejected from a recording head by the action of thermal energy to record images on a recording medium; the ink containing at least (a) a pigment, (b) a dispersing agent, (c) a liquid medium and (d) an alkali metal salt of a malonic acid derivative, represented by the following Formula (1): wherein R represents an alkyl group, and M represents an alkali metal.