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: 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: 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: A toner including a crystalline resin wherein the crystalline resin contains a crystalline resin having a urethane bond, a urea bond or both thereof, and wherein the crystalline resin has an average crystallite diameter of 20 nm to 70 nm.

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: A copolymer includes structural units having the following formulae (1) and (2): wherein each of R1 and R2 independently represents a hydrogen atom or a methyl group; X represents a hydrogen atom or a cationic ion; and L represents a single bond or —(CH2)n—O—, the oxygen atom of which is bonded with the biphenyl; and n represents an integer of from 2 to 18.

Abstract: An ink includes water, a pigment, and a copolymer, wherein the copolymer contains a structure unit represented by the following Chemical formula 1, where R1 represents a hydrogen atom or a methyl group, M1+ and M2+ each, independently represent monovalent cations, n and m each, independently represent 0 or integers of from 1 to 6 excluding a case where both are 0 and a structure unit represented by the following Chemical formula 2, where R2 represents a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 18 carbon atoms.

Abstract: An ink includes water, a pigment, and a copolymer, wherein the copolymer contains a structure unit represented by the following Chemical formula 1, where R1 represents a hydrogen atom or a methyl group, M1+ and M2+ each, independently represent monovalent cations, n and m each, independently represent 0 or integers of from 1 to 6 excluding a case where both are 0 and a structure unit represented by the following Chemical formula 2, where R2 represents a hydrogen atom or a methyl group, Y represents an alkylene group having 2 to 18 carbon atoms.

Abstract: A copolymer includes structural units having the following formulae (1) and (2): wherein each of R1 and R2 independently represents a hydrogen atom or a methyl group; X represents a hydrogen atom or a cationic ion; and L represents a single bond or —(CH2)n—O—, the oxygen atom of which is bonded with the biphenyl; and n represents an integer of from 2 to 18.

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 electrophotographic toner including: a binder resin, wherein the binder resin has one glass transition temperature Tg and the glass transition temperature Tg of the binder resin is within 25° C. to 65° C. as measured in second heating with a differential scanning calorimeter at a heating rate of 5° C./min, and wherein a phase image of the binder resin obtained with an atomic force microscope (AFM) of tapping mode contains first phase difference regions and a second phase difference region such that the first phase difference regions are dispersed in the second phase difference region, where the first phase difference regions correspond to greater phase difference regions and the second phase difference region corresponds to a smaller phase difference region when an intermediate value between a maximum value and a minimum value of the phase differences is used as a threshold.

Abstract: A resin for use in toner is provided. The resin comprises an oligomer segment and a soft segment. The oligomer segment comprises a polyhydroxycarboxylic skeleton and an aromatic diol skeleton.

Abstract: A resin for toner contains a polyhydroxycarboxylic acid skeleton and a rigid skeleton.

Abstract: A toner including a crystalline resin wherein the crystalline resin contains a crystalline resin having a urethane bond, a urea bond or both thereof, and wherein the crystalline resin has an average crystallite diameter of 20 nm to 70 nm.

Abstract: A colorless transparent toner containing a crystalline resin having a urethane bond and/or a urea bond.

Abstract: The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from ?20° C. to 20° C., and a second glass transition temperature of from 35° C. to 65° C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5° C./min.

Abstract: An electrophotographic toner including: a binder resin, wherein the binder resin has one glass transition temperature Tg and the glass transition temperature Tg of the binder resin is within 25° C. to 65° C. as measured in second heating with a differential scanning calorimeter at a heating rate of 5° C./min, and wherein a phase image of the binder resin obtained with an atomic force microscope (AFM) of tapping mode contains first phase difference regions and a second phase difference region such that the first phase difference regions are dispersed in the second phase difference region, where the first phase difference regions correspond to greater phase difference regions and the second phase difference region corresponds to a smaller phase difference region when an intermediate value between a maximum value and a minimum value of the phase differences is used as a threshold.

Abstract: A toner including a resin particle (C) is provided. The resin particle (C) includes a resin particle (B) and; a resin particle (A) or covering layer (P) that is adhered to a surface of the resin particle (B). The resin particle (B) includes a resin (b) having a polyhydroxycarboxylic acid skeleton. The resin particle (A) or covering layer (P) includes a resin (a). The resin (a) is a polyester resin having a polybasic acid unit and a polyol unit and has a weight average molecular weight within a range from 9,500 to 100,000.

Abstract: An electrophotographic toner, including: a binder resin; a colorant; and an organically-modified layered inorganic mineral, wherein the binder resin contains 50% by mass or more of a crystalline resin relative to the binder resin, and the crystalline resin contains a resin having a sulfonic acid group, and wherein an amount of the sulfonic acid group is 0.1% by mass to 2.0% by mass relative to the resin having the sulfonic acid group.

Abstract: A toner including a resin particle (C) is provided. The resin particle (C) includes a resin particle (B) and a resin particle (A). The resin particle (B) includes a resin (b). The resin particle (A) or covering layer (P) includes a resin (a). The resin particle (A) or covering layer (P) is adhered to a surface of the resin particle (B). The resin (a) is a polyester resin. The resin (a) has a total acid value of 15 to 36 mgKOH/g. The resin particle (A) or covering layer (P) has a surface acid value of 10 to 27 mgKOH/g.