# US 7,611,571 B2 · Ink, ink jet recording method, ink cartridge, recording unit, and ink jet recording apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,611,571 B2 - Document ID: US7611571B2 - Status: Granted - Kind: B2 - Application number: 12/110,596 - Filed: 2008-04-28 - Published: 2008-11-06 - Granted: 2009-11-03 - Earliest claimed: 2007-05-01 - Assignees: Canon Kabushiki Kaisha - Inventors: Tomohiro Yamashita; Jun Yoshizawa; Daiji Okamura - Web page: https://patentgrep.com/patent/US7611571B2 ## CPC - C09D 11/32: characterised by colouring agents - 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 An ink having a cyan color is provided which can form images excellent in ozone resistance in such a high level as to exceed anticipation and having a preferable color tone. The ink includes at least two coloring materials of a first coloring material and a second coloring material, wherein the first coloring material is a compound having a copper phthalocyanine skeleton with a specific structure and the second coloring material is a compound having a copper phthalocyanine skeleton with a specific structure that is different from the first coloring material. ## Claims ### Claim 1 An ink comprising at least two coloring materials of a first coloring material and a second coloring material, wherein the first coloring material is a compound represented by the following general formula (I): wherein A, B, C, and D each independently represent a six-membered ring having aromaticity and at least one of A, B, C, and D in the general formula (I) is a pyridine ring or a pyrazine ring, M's each independently represent a hydrogen atom, alkali metal, ammonium, or organic ammonium, E's each independently represent an alkylene group, X's each independently represent a sulfo-substituted anilino group, a carboxyl-substituted anilino group, or a phosphono-substituted anilino group, and the substituted anilino groups may have 1 to 4 of at least one substituent selected from the group consisting of a sulfonic acid group, a carboxyl group, a phosphono group, a sulfamoyl group, a carbamoyl group, a hydroxyl group, an alkoxy group, an amino group, an alkylamino group, a dialkylamino group, an arylamino group, a diarylamino group, an acetylamino group, an ureido group, an alkyl group, a nitro group, a cyano group, halogen, an alkylsulfonyl group, and an alkylthio group, Y's each independently represent a hydroxyl group or an amino group, and 1, m and n satisfy 0≦1≦2, 0≦m≦3 and 0.1≦n≦3, and 1+m+n=1 to 4, and wherein the second coloring material is a compound represented by the general formula (II): wherein X1, X2, X3 and X4 each independently represent —SO-Z, —SO2-Z, —SO2NR1R2, a sulfonic acid group, —CONR1R2, or CO2R1, wherein Z's each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, R1 and R2 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, Y1, Y2, Y3, Y4, Y5, Y6, Y7 and Y8 each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a cyano group, a substituted or unsubstituted alkoxy group, an amide group, an ureido group, a sulfonamide group, a substituted or unsubstituted carbamoyl group, a substituted or unsubstituted sulfamoyl group, a substituted or unsubstituted alkoxycarbonyl group, a carboxyl group or a sulfonic acid group, and a1, a2, a3 and a4 represent the numbers of substituents of X1, X2, X3 and X4, respectively, and each independently represent an integer of 1 or 2. ### Claim 2 (depends on 1) The ink according to claim 1, wherein a content (% by mass) of the first coloring material in the ink is from 1.25 times or more to 5.0 times or less as much as a content (% by mass) of the second coloring material in the ink. ### Claim 3 (depends on 1) An ink jet recording method in which ink is ejected by an ink jet system to perform recording on a recording medium, wherein the ink is an ink according to claim 1. ### Claim 4 (depends on 1) An ink cartridge provided with an ink storage portion for storing ink, wherein the ink is an ink according to claim 1. ### Claim 5 (depends on 1) A recording unit provided with an ink storage portion for storing ink and a recording head for ejecting ink, wherein the ink is an ink according to claim 1. ### Claim 6 (depends on 1) An ink jet recording apparatus provided with an ink storage portion for storing ink and a recording head for ejecting ink, wherein the ink is an ink according to claim 1. ### Claim 7 (depends on 1) The ink according to claim 1, wherein a dispersion distance, d value, between molecular aggregates in an ink, obtained by a small-angle X-ray scattering method, satisfies the following conditions: dA+B>dA and dA+B>dB wherein dA (nm) is a d value of the first coloring material, dB (nm) is a d value of the second coloring material, and dA+B (nm) is a d value when the first coloring material and the second coloring material are mixed.