Abstract: An ink set which includes a first ink composition that contains a coloring agent, a surfactant in an amount of A1 mass %, a hydrophobic organic solvent in an amount of A2 mass %, and water, the first ink composition being used to form a first image, and a second ink composition that contains a coloring agent, a surfactant in an amount of B1 mass %, a hydrophobic organic solvent in an amount of B2 mass %, and water, the second ink composition being used to form a second image on the first image. The surfactant is a specific silicone-based surfactant; the octanol/water partition coefficient of the hydrophobic organic solvent is not less than 2.00 but less than 3.50; and the following formula 0.05?(0.5×(B1?A1)+(B2?A2))?0.70 is satisfied.

Abstract: An ink composition including a water-insoluble coloring agent, a dispersing agent, a resin A, a resin B, and water, in which the resin A is obtained through polymerization of at least a C1-C4 alkyl methacrylate and a C2-C6 alkyl acrylate, and the resin B is obtained through polymerization of at least a styrene-based monomer and divinyl benzene. An inkjet-recording method in which the ink composition is used; a recording medium to which the ink composition is attached; and an inkjet printer including a container filled with the ink composition.

Abstract: An ink which comprises a water-insoluble colorant, a dispersant, a polymer resin, and water. The polymer resin is one of four monomers which are methacrylic acid and three monomers selected respectively from among C1- to C4-alkyl methacrylates, C6- to C10-alkyl acrylates, and unsaturated C2- to C4-alkyl methacrylates; and a reactive emulsifier having a radical-polymerizable double bond in the molecule. An ink-jet recording method in which the ink is used; a recording medium to which the ink has been adhered; and an ink-jet printer including a vessel filled with the ink.

Abstract: A pretreatment liquid containing a multivalent metal salt, a cationized guar gum, and water, and an image forming method using the pretreatment liquid. The pretreatment liquid is applied to recording media before an aqueous color ink containing colorant is applied to the recording media.

Abstract: An ink set which includes a first ink composition that contains a coloring agent, a surfactant in an amount of A1 mass %, a hydrophobic organic solvent in an amount of A2 mass %, and water, the first ink composition being used to form a first image, and a second ink composition that contains a coloring agent, a surfactant in an amount of B1 mass %, a hydrophobic organic solvent in an amount of B2 mass %, and water, the second ink composition being used to form a second image on the first image. The surfactant is a specific silicone-based surfactant; the octanol/water partition coefficient of the hydrophobic organic solvent is not less than 2.00 but less than 3.50; and the following formula 0.05?(0.5×(B1?A1)+(B2?A2))?0.70 is satisfied.

Abstract: A cleaning solution containing a compound represented by formula (1), a compound represented by formula (2), and water; and an inkjet printer cleaning method using the same. R1—O(EO)m(PO)nH??(1) R2—O(EO)LH??(2) In formula (1), R1 represents a linear or branched C1-C30 alkyl group. EO represents an ethyleneoxy group, and PO represents a propyleneoxy group. m and n each independently represent an integer of 1-5. m:n, which is the ratio between m and n, is at least 1:2 and smaller than 3:2. In formula (2), R2 represents a linear or branched C1-C30 alkyl group, or an aryl group. EO represents an ethyleneoxy group. L represents an integer of at least 10. Formula (1): R1—O(EO)m(PO)nH. Formula (2): R2—O(EO)LH.

Abstract: An ink that contains a water-insoluble colorant, an oxidized polyethylene wax, a compound that is represented by formula (1) or formula (2) and has an HLB value of 7.5-20.0, and water; an inkjet printing method that uses the ink; and a printing medium to which the ink is adhered. In the formulas, R1-R3 are each independently a linear or branched C7-C40 hydrocarbon group, EO is an ethyleneoxy group, and PO is a propyleneoxy group. m1 and m2 are average values and are 1-300, and n1 and n2 are average values and are 0-10.

Abstract: An ink which comprises a water-insoluble colorant, a dispersant, a polymer resin, and water. The polymer resin is one of four monomers which are methacrylic acid and three monomers selected respectively from among C1- to C4-alkyl methacrylates, C6- to C10-alkyl acrylates, and unsaturated C2- to C4-alkyl methacrylates; and a reactive emulsifier having a radical-polymerizable double bond in the molecule. An ink-jet recording method in which the ink is used; a recording medium to which the ink has been adhered; and an ink-jet printer including a vessel filled with the ink.

Abstract: A cleaning solution containing a compound represented by formula (1), a compound represented by formula (2), and water; and an inkjet printer cleaning method using the same. R1—O(EO)m(PO)nH??(1) R2—O(EO)LH??(2) In formula (1), R1 represents a linear or branched C1-C30 alkyl group. EO represents an ethyleneoxy group, and PO represents a propyleneoxy group. m and n each independently represent an integer of 1-5. m:n, which is the ratio between m and n, is at least 1:2 and smaller than 3:2. In formula (2), R2 represents a linear or branched C1-C30 alkyl group, or an aryl group. EO represents an ethyleneoxy group. L represents an integer of at least 10. Formula (1): R1—O(EO)m(PO)nH. Formula (2): R2—O(EO)LH.

Abstract: A pretreatment liquid containing a multivalent metal salt, a cationized guar gum, and water, and an image forming method using the pretreatment liquid. The pretreatment liquid is applied to recording media before an aqueous color ink containing colorant is applied to the recording media.

Abstract: A cleaning liquid including a compound represented by the following formula (1): (CH3)3C—R—O(C4H8O)L—(C3H6O)m—(C2H4O)n—H??(1) and water; and a method of cleaning an ink-jet printer using the cleaning liquid. In the formula (1), R represents a linear or branched C1 to C5 hydrocarbon group, and L, m, and n each represent the average number of repeats, and L?0, m?0, n>0, and (L+m)/n=1.5/1 to 1/1.5.

Abstract: A cleaning liquid including a compound represented by the following formula (1): (CH3)3C—R—O(C4H8O)L—(C3H6O)m—(C2H4O)n—H ??(1) and water; and a method of cleaning an ink-jet printer using the cleaning liquid. In the formula (1), R represents a linear or branched C1 to C5 hydrocarbon group, and L, m, and n each represent the average number of repeats, and L?0, m?0, n>0, and (L+m)/n=1.5/1 to 1/1.5.

Abstract: An aqueous pigment ink composition having high scratch resistance and good ejection properties and redispersibility, an ink jet recording method using the aqueous pigment ink composition, and a colored substance including the aqueous pigment ink composition. The ink composition includes a colorant, a resin, and water. The colorant includes a coloring matter that is substantially insoluble in water. The resin is a polymer produced by polymerization of at least one monomer represented by the following formula (1) in which R1 denotes a hydrogen atom or a methyl group, and R2 denotes a methyl group, a C8 alkyl group, or the like.

Abstract: An aqueous pigment ink composition having high scratch resistance and good ejection properties and redispersibility, an ink jet recording method using the aqueous pigment ink composition, and a colored substance including the aqueous pigment ink composition. The ink composition includes a colorant, a resin, and water. The colorant includes a coloring matter that is substantially insoluble in water. The resin is a polymer produced by polymerization of at least one monomer represented by the following formula (1) in which R1 denotes a hydrogen atom or a methyl group, and R2 denotes a methyl group, a C8 alkyl group, or the like.