INKJET INK SET

• Main Authors: NAKAGAWA TOMOHIRO, KATO KEITA, KUDO MAKI, FUJII ICHIRO
• Format: Patent
• Language: English
• Published: 17.01.2013
• Subjects: ADHESIVES; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COLOUR PRINTING; CORRECTING FLUIDS; CORRECTION OF TYPOGRAPHICAL ERRORS; DYES; FILLING PASTES; i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; INKS; LINING MACHINES; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; PERFORMING OPERATIONS; POLISHES; PRINTING; PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; SELECTIVE PRINTING MECHANISMS; STAMPS; TRANSPORTING; TYPEWRITERS; USE OF MATERIALS THEREFOR; WOODSTAINS

PROBLEM TO BE SOLVED: To provide an inkjet ink set or the like, which is excellent in discharge stability and can prevent color bleeds or curls from occurring between black color and colors other than the black even if an image is formed on a paper.SOLUTION: A black ink comprises water, a water-soluble organic solvent A, a water-soluble organic solvent B, a water-soluble organic solvent C, and a colorant, wherein: the total content of the solvents A, B and C is 25 to 50 mass%; and the content of the solvent A is equal to or larger than the total content of the solvent B and C. Inks of colors other than the black contains the water, the solvent A, the solvent B, and the colorant, but does not contain the solvent C, wherein: the total content of the solvent A and the solvent B is 25 to 50 mass%; the total content of the solvent A is equal to or lower than the solvent B; the equilibrium water contents of the solvent A, solvent B, and solvent C at 23°C and at 80% relative humidity (RH) are 41 to 49 mass%, 35 to 39 mass%, and 11 to 24 mass%, respectively; and when the amount of evaporation of water is 30 mass%, the viscosity of the black ink is larger than those of color inks other than the black ink.