| 摘要 |
PURPOSE:The titled composition that contains a coloring agent and an additive controlled so that the out of roundness of a dot is above a specific value when the dot is formed on a sheet of recording paper having a specific basis weight and that is excellent in the high density of the dot, ejection stability and in particular, preservation stability. CONSTITUTION:The ink composition for ink jet recording that contains a coloring agent and an additive controlled so that the out of roundness D represented by a formula D=4piXS/L<2>, where S represents area of the dot and L circumference of the dot, has a value of 0.75 or more when the dot is formed on a sheet of recording paper having a basis weight of 50-80g/m<2>. In preferred embodiment of the compositon, the viscosity has a value of 1.8-15.0cP (at 30 deg.C), the coloring agent is a direct dye (e.g. formulaIor II) having a chemical structural formula that has at least three amino groups (precursors) at the terminal of the structural formula or in a place where the free motion is not restricted by a chemical bonding force such as a hydrogen bond or the like, and one of the additives is a stabilizer comprising an acetate. |
