Abstract: Provided is an aqueous in ink with which the granularity of an ink coating caused in printing on a less-ink-absorbent or non-ink-absorbent recording medium is reduced while sufficient image fastness is achieved even printing on an ink-absorbent recording medium. The present invention relates to an ague-gas ink composition for use in an inkjet recording method. The aqueous ink composition contains an aqueous medium, a pigment, and a dye, and a combination of the pigment and the dye is a predetermined combination.

Abstract: A problem to be solved by the invention is to provide an aqueous ink capable of forming a clear print image without causing deterioration in print quality due to uneven drying (mottling) of the ink even when continuous printing is performed for a long period of time or when printing is resumed after printing is suspended for several minutes to several hours. The invention relates to an aqueous ink containing: an acetylene-based surfactant (A); a nonionic surfactant (B) other than the acetylene-based surfactant (A); and an aqueous medium (C), in which the nonionic surfactant (B) contains a nonionic surfactant that satisfies at least one of the following three requirements: (i) having an HLB of less than 13.5, (ii) having a clouding point of 75° C. or lower, and (iii) having no clouding point.

Abstract: A problem to be solved by the invention is to provide an aqueous ink capable of forming a clear print image without causing deterioration in print quality due to uneven drying (mottling) of the ink even when continuous printing is performed for a long period of time or when printing is resumed after printing is suspended for several minutes to several hours. The invention relates to an aqueous ink containing: an acetylene-based surfactant (A); a nonionic surfactant (B) other than the acetylene-based surfactant (A); and an aqueous medium (C), in which the nonionic surfactant (B) contains a nonionic surfactant that satisfies at least one of the following three requirements: (i) having an HLB of less than 13.5, (ii) having a clouding point of 75° C. or lower, and (iii) having no clouding point.

Abstract: The problem to be solved by the present invention is to provide an ink that can be used f producing a print having no streaks even in a case where the distance between the surface of a recording medium such as a cardboard and an ink jet head is long. The present invention relates to an ink for use in an ink jet recording method in which the distance from a surface (x) having an ink discharge port of an ink jet head to a position (y) where a line perpendicular to the surface (x) intersects with a recording medium is 2 mm or more, the ink having a viscosity in the range of 2 mPa·s or more and less than 9 mPa·s and a surface tension in the range of 20 mN/m to 40 mN/m.

Abstract: The problem to be solved by the present invention is to provide an ink that can be used f producing a print having no streaks even in a case where the distance between the surface of a recording medium such as a cardboard and an ink jet head is long. The present invention relates to an ink for use in an ink jet recording method in which the distance from a surface (x) having an ink discharge port of an ink jet head to a position (y) where a line perpendicular to the surface (x) intersects with a recording medium is 2 mm or more, the ink having a viscosity in the range of 2 mPa·s or more and less than 9 mPa·s and a surface tension in the range of 20 mN/m to 40 mN/m.