# US 7,607,772 B2 · Water-based ink set for ink-jet recording and ink-jet recording method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,607,772 B2 - Document ID: US7607772B2 - Status: Granted - Kind: B2 - Application number: 11/407,291 - Filed: 2006-04-20 - Published: 2006-10-26 - Granted: 2009-10-27 - Earliest claimed: 2005-04-21 - Assignees: Brother Kogyo Kabushiki Kaisha - Inventors: Narumi Koga; Masaya Fujioka; Tomoyo Hamajima; Narumi Kawai - Web page: https://patentgrep.com/patent/US7607772B2 ## CPC - C09D 11/40: Ink-sets specially adapted for multi-colour inkjet printing - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract The water-based ink set for ink-jet recording includes a cyan ink and a blue ink with dynamic surface tensions thereof satisfying the following inequalities (ICB), (IICB), (IIICB) and (IVCB) σ30C≦about 49 mN/m (ICB) σ30C+σ30B≦about 100 mN/m (IICB) wherein σ30C is the dynamic surface tension of the cyan ink at a lifetime of 30 ms and σ30B is the dynamic surface tension of the blue ink at a lifetime of 30 ms, σ1000B≧about 36 mN/m (IIICB) σ1000C+σ1000B≧about 70 mN/m (IVCB) wherein σ1000C is the dynamic surface tension of the cyan ink at a lifetime of 1,000 ms and σ1000B is the dynamic surface tension of the blue ink at a lifetime of 1,000 ms. ## Claims ### Claim 1 A water-based ink set for ink-jet recording comprising a cyan ink and a blue ink, wherein dynamic surface tensions of the cyan ink and the blue ink as determined by a maximum bubble pressure method at a measurement temperature of 25° C. satisfy the following inequalities (ICB), (IICB), (IIICB) and (IVCB) σ30C≦about 49 mN/m (ICB) σ30C+σ30B≦about 100 mN/m (IICB) wherein σ30C is dynamic surface tension of the cyan ink at a lifetime of 30 ms and σ30B is the dynamic surface tension of the blue ink at a lifetime of 30 ms, σ1000B≧about 36mN/m (IIICB) σ1000C+σ1000B≧about70mN/m (IVCB) wherein σ1000C is dynamic surface tension of the cyan ink at a lifetime of 1,000 ms and σ1000B is the dynamic surface tension of the blue ink at a lifetime of 1,000 ms. ### Claim 2 (depends on 1) The water-based ink set for ink-jet recording according to claim 1, wherein: the cyan ink has a lightness (L*) in a range of from about 60 to about 85 in the L*a*b* colorimetric system; and the blue ink has a lightness(L*) in the range of from about 35 to about 45 in the L*a*b* colorimetric system. ### Claim 3 (depends on 1) The water-based ink set for ink-jet recording according to claim 1, wherein the cyan ink has a hue angle (h) in a range of from about 215° to about 225° in the L*a*b* colorimetric system. ### Claim 4 (depends on 1) The water-based ink set for ink-jet recording according to claim 1, further comprising a green ink, wherein dynamic surface tensions of the cyan ink and the green ink as determined by a maximum bubble pressure method at a measurement temperature of 25° C. satisfy the following inequalities (ICG), (IICG), (IIICG) and (IVCG) σ30C≦about 49 mN/m (ICG) σ30C+σ30G≦100 mN/m (IICG) wherein σ30C is dynamic surface tension of the cyan ink at a lifetime of 30 ms and σ30G is the dynamic surface tension of the green ink at a lifetime of 30 ms, σ1000G≧about 36 mN/m (IIICG) σ1000C+σ1000G≧about 70 mN/m (IVCG) wherein σ1000C is dynamic surface tension of the cyan ink at a lifetime of 1,000 ms and σ1000G is the dynamic surface tension of the green ink at a lifetime of 1,000 ms. ### Claim 5 (depends on 4) The water-based ink set for ink-jet recording according to claim 4: wherein: the green ink has a lightness (L*) in a range of from about 35 to about 60 in the L*a*b* colorimetric system. ### Claim 6 (depends on 4) The water-based ink set for ink-jet recording according to claim 4, wherein: the green ink has a hue angle (h) in a range of from about 175° to about 215° in the L*a*b* colorimetric system. ### Claim 7 (depends on 1) The water-based ink set for an ink-jet recording according to claim 1, further comprising a yellow ink and/ or a magenta ink. ### Claim 8 (depends on 1) The water-based ink set for ink-jet recording according to claim 1, wherein: the blue ink has a hue angle (h) in a range of from about 270° to about 285° in the L*a*b* colorimetric system. ### Claim 9 A water-based ink set for ink-jet recording comprising a cyan ink and a green ink, wherein dynamic surface tensions of the cyan ink and the green ink as determined by a maximum bubble pressure method at a measurement temperature of 25° C. satisfy the following inequalities (ICG), (IICG), (IlICG) and (IVCG) σ30C≦about 49 mN/m (ICG) σ30C+σ30G≦about 100 mN/m (IICG) wherein σ30C is dynamic surface tension of the cyan ink at a lifetime of 30 ms and σ30G is the dynamic surface tension of the green ink at a lifetime of 30 ms, σ1000G≧about 36 mN/m (IIICG) σ1000C+σ1000G≧about 70 mN/m (IVCG) wherein σ1000C is dynamic surface tension of the cyan ink at a lifetime of 1,000 ms and σ1000G is the dynamic surface tension of the green ink at a lifetime of 1,000 ms. ### Claim 10 (depends on 9) The water-based ink set for ink-jet recording according to claim 9, wherein: the cyan ink has a lightness (L*) in a range of from about 60 to about 85 in the L*a*b* colorimetric system; and the green ink has a lightness (L*) in a range of from about 35 to about 60 in the L*a*b* colorimetric system. ### Claim 11 (depends on 9) The water-based ink set for ink-jet recording according to claim 9, wherein the cyan ink has a hue angle (h) in a range of from about 215° to about 255° in the L*a*b* colorimetric system. ### Claim 12 (depends on 9) The water-based ink set for ink-jet recording according to claim 9, further comprising a yellow ink and/or a magenta ink. ### Claim 13 (depends on 9) The water-based ink set for ink-jet recording according to claim 9, wherein: the green ink has a hue angle (h) in a range of from about 175° to about 215° in the L*a*b colorimetric system.