Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.

Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.

Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.

Abstract: An image forming method includes applying an ink for the first time to a recording medium to form an image and rolling up the recording medium in a roll form, wherein the recording medium is continuous paper, the ink includes an organic solvent and a coloring material, and the image recorded matter has a tackiness power of from 80 to 110 nN.

Abstract: A copolymer including a structural unit represented by General Formula (1) below, and a structural unit represented by General Formula (2) below, where, in General Formula (1), R1 is a hydrogen atom or a methyl group, L1 is an alkylene group having 2 or greater carbon atoms but 5 or less carbon atoms, and X is a hydrogen atom or a cation, where, in General Formula (2), R2 is a hydrogen atom or a methyl group and L2 is an alkylene group having 2 or greater carbon atoms but 18 or less carbon atoms.

Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.

Abstract: An ink includes a pigment, a wax, a water soluble solvent including a solvent having an SP value of from 9.0 to 11.0, and water, wherein the mass ratio of the content of the wax in the ink to the content of the solvent having an SP value of from 9.0 to 11.0 is in a range of from 1.0:2.5 to 1.0:25.0.

Abstract: An image forming method includes applying an ink for the first time to a recording medium to form an image and rolling up the recording medium in a roll form, wherein the recording medium is continuous paper, the ink includes an organic solvent and a coloring material, and the image recorded matter has a tackiness power of from 80 to 110 nN.

Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.

Abstract: An image forming method includes applying an ink for the first time to a recording medium to form an image and rolling up the recording medium in a roll form, wherein the recording medium is continuous paper, the ink includes water, an organic solvent, and a coloring material, and the image has a tackiness power of from 80 to 110 nN.

Abstract: An ink includes an organic solvent and polyethylene wax, wherein the polyethylene wax has a penetration of 1.2 or less as measured according to JIS K2235 format.

Abstract: To provide a copolymer including: a structural unit represented by the following General Formula (1) where X represents a hydrogen atom or a cation; a structural unit expressed by the following Structural Formula (1); and a structural unit represented by the following General Formula (2) where R is a hydrogen atom or a methyl group, L is a single bond or —(CH2)n—O—CO— where n is an integer in a range of from 2 through 18, and a carbonyl carbon atom in the —(CH2)n—O—CO— is bound to naphthyl.

Abstract: Provided is an ink containing a copper phthalocyanine pigment, wherein an absorbance ratio (Y/X) of a local minimum absorbance Y of the ink in a wavelength range of from 665 nm through 675 nm to a local maximum absorbance X of the ink in a wavelength range of from 610 nm through 620 nm is 0.660 or greater but 0.740 or less.

Abstract: To provide a copolymer including: a structural unit represented by the following General Formula (1) where X represents a hydrogen atom or a cation; a structural unit expressed by the following Structural Formula (1); and a structural unit represented by the following General Formula (2) where R is a hydrogen atom or a methyl group, L is a single bond or —(CH2)n—O—CO— where n is an integer in a range of from 2 through 18, and a carbonyl carbon atom in the —(CH2)n—O—CO— is bound to naphthyl.

Abstract: A copolymer including a structural unit represented by General Formula (1) below, and a structural unit represented by General Formula (2) below, where, in General Formula (1), R1 is a hydrogen atom or a methyl group, L1 is an alkylene group having 2 or greater carbon atoms but 5 or less carbon atoms, and X is a hydrogen atom or a cation, where, in General Formula (2), R2 is a hydrogen atom or a methyl group and L2 is an alkylene group having 2 or greater carbon atoms but 18 or less carbon atoms.

Abstract: Provided is an ink including: copolymer including at least one of structural unit of formula (1) and structural unit of formula (2); pigment having acid value of ?15 ?mol/g and represented by formula (3); water; and water-soluble organic solvent. In formula (1), R1 represents hydrogen or methyl group. L1 represents alkylene group including 2-18 carbon atoms. In formula (2), R1 represents hydrogen or methyl group. L2 represents single bond or —(CH2)n-O— of which oxygen is bound with biphenyl. n represents integer of 2 through 18. In formula (3), R1 represents any one of hydrogen, halogen, alkyl group including 1-4 carbon atoms, alkoxy group including 1-4 carbon atoms, hydroxy, nitro, and alkyl substituted or unsubstituted amino group including 1-4 carbon atoms. n represents integer of 1 through 5. When n is a plural number, R1 may be identical or different. R2, R3, and R4 represent alkyl group including 1-4 carbon atoms.

Abstract: A copolymer includes a structure unit represented by Chemical Formula I; and a structure unit represented by Chemical Formula II, where R1 and R2 each, independently represent hydrogen atoms or methyl groups, X represents a hydrogen atom or a cation, and L represents an alkylene group having 2 to 18 carbon atoms.

Abstract: An image forming method includes applying an ink for the first time to a recording medium to form an image and rolling up the recording medium in a roll form, wherein the recording medium is continuous paper, the ink includes water, an organic solvent, and a coloring material, and the image has a tackiness power of from 80 to 110 nN.

Abstract: A copolymer includes the structure unit represented by the following Chemical formula 1 and the structure unit represented by the following Chemical formula 2, where R1 and R2 each, independently represent hydrogen atoms or methyl groups, and n represents a value in the range of from 1 to 90, where R3 represents a hydrogen atom or a methyl group and L represents an alkylene group having 2 to 18 carbon atoms.

Abstract: An ink set includes an ink A including water, a first organic solvent, and a first pigment and an ink B including water, a second organic solvent, a second pigment, and a urethane resin particle. The first organic solvent includes at least one of N,N-dimethyl-?-buthoxy propionamide, N,N-dimethyl-?-methoxy propionamide, and 3-ethyl-3-hydroxymethyl oxetane and has a mixing solubility parameter A of 10.00 to less than 13.00 and the second organic solvent has a mixing solubility parameter B of 13.00 to 16.00.