Abstract: Provided are a method for producing a peptide compound including a step of using a condensed polycyclic aromatic hydrocarbon compound represented by Formula (1); a protective group-forming reagent including the compound; and the compound. In Formula (1), a ring A represents a condensed polycyclic aromatic hydrocarbon ring, YA's each independently represent —CH2OH, —CH2NHR, —CH2SH, or —CH2X0, where R represents a hydrogen atom, an alkyl group, or an aralkyl group, and X0 represents Cl, Br, or I, k represents an integer of 1 to 5, n represents 1 or 2, and RA's each independently represent an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group.

Abstract: Provided are a method for producing a peptide compound including a step of using an aromatic heterocyclic compound represented by Formula (1) represented by Formula (1); a protective group-forming reagent including the compound; and the compound. In Formula (1), a ring A represents an aromatic heterocyclic ring, YA's each independently represent —OH, —NHR, —SH, or —X0, where X0 represents Cl, Br, or I, RA and RC each independently represent an aliphatic hydrocarbon group or an organic group having an aliphatic hydrocarbon group, RBs' each independently represent a monovalent aliphatic hydrocarbon group, a (1+c)-valent aromatic group, or a (1+c)-valent heteroaromatic group, where, in a case where both a and c is 0, RB is a monovalent aliphatic hydrocarbon group, and the number of carbon atoms in at least one aliphatic hydrocarbon group of RA, RB, or RC is 12 or more.

Abstract: The magnetic recording medium contains, in a magnetic layer, a fatty acid ester and a polyester resin having a number average molecular weight of greater than or equal to 1,000 but less than 20,000, and containing a structural unit derived from a polyvalent carboxylic acid and a structural unit derived from a polyol, as well as 10 mol % to 50 mol % of a structural unit, derived from a cyclic polyvalent carboxylic acid selected from the group consisting of an alicyclic polyvalent carboxylic acid and an aromatic polyvalent carboxylic acid, per 100 mol % of a combined total of the above structural units, and one or more partial structures selected from the group consisting of the following partial structures: wherein each of L1 and L2 independently denotes a divalent connecting group, and each of Z1 and Z2 independently denotes a monovalent group denoted by —OM or a monovalent group denoted by —O?A+.

Abstract: The metal oxide particle dispersion for manufacturing a particulate magnetic recording medium contains metal oxide particles, solvent, and a polyester compound having one or more groups selected from the group consisting of a carboxyl group and a salt thereof, a phosphoric acid group and a salt thereof, a hydroxyl group and a nitrogen-substituted alkylene group, but substantially not containing ferromagnetic powder.

Abstract: The magnetic recording medium composition contains ferromagnetic powder, binder, and a crosslinkable component selected from the group consisting of a component capable of forming a crosslinking structure by a radical reaction, a component capable of forming a crosslinking structure by an ionic reaction, and a component capable of forming a crosslinking structure by a pericyclic reaction, wherein the crosslinkable component contains at least polyester, and the polyester has a weight average molecular weight ranging from 1,000 to 20,000, as well as contains, per molecule, one or more acidic groups, and one or more reactive groups selected from the group consisting of a radical reactive group, an ionic reactive group, and a pericyclic reactive group.

Abstract: The magnetic recording medium contains, in a magnetic layer, a fatty acid ester and a polyester resin having a number average molecular weight of greater than or equal to 1,000 but less than 20,000, and containing a structural unit derived from a polyvalent carboxylic acid and a structural unit derived from a polyol, as well as 10 mol % to 50 mol % of a structural unit, derived from a cyclic polyvalent carboxylic acid selected from the group consisting of an alicyclic polyvalent carboxylic acid and an aromatic polyvalent carboxylic acid, per 100 mol % of a combined total of the above structural units, and one or more partial structures selected from the group consisting of the following partial structures: wherein each of L1 and L2 independently denotes a divalent connecting group, and each of Z1 and Z2 independently denotes a monovalent group denoted by —OM or a monovalent group denoted by —O?A+.

Abstract: The metal oxide particle dispersion for manufacturing a particulate magnetic recording medium contains metal oxide particles, solvent, and a polyester compound having one or more groups selected from the group consisting of a carboxyl group and a salt thereof, a phosphoric acid group and a salt thereof, a hydroxyl group and a nitrogen-substituted alkylene group, but substantially not containing ferromagnetic powder.

Abstract: The magnetic recording medium composition contains ferromagnetic powder, binder, and a crosslinkable component selected from the group consisting of a component capable of forming a crosslinking structure by a radical reaction, a component capable of forming a crosslinking structure by an ionic reaction, and a component capable of forming a crosslinking structure by a pericyclic reaction, wherein the crosslinkable component contains at least polyester, and the polyester has a weight average molecular weight ranging from 1,000 to 20,000, as well as contains, per molecule, one or more acidic groups, and one or more reactive groups selected from the group consisting of a radical reactive group, an ionic reactive group, and a pericyclic reactive group.

Abstract: An ink composition of the present invention includes: cross-linked particles containing a quinacridone solid solution pigment including at least two types of quinacridone-based compound; a water-soluble polymerizable compound; a polymerization initiator; and water. By selectively using cross-linked solid solution pigments as pigments (colorants), along with excellent adhesion of the image, the stability over time of the ink composition itself is excellent.

Abstract: Disclosed is an ink composition with excellent adhesiveness of an image on a recording medium and recoverability after being left for a period. The ink composition of the present invention contains coloring particles that include a quinacridone solid solution pigment including two or more types of quinacridone-based compounds, a synergist including a basic group, and a high-molecular weight vinyl polymer, a water-soluble polymerizable compound, a polymerization initiator and water.

Abstract: The invention provides a maintenance liquid, containing water, a water-soluble organic solvent, and at least one of a water-soluble silicate represented by Formula (1) or colloidal silica: xM2O.ySiO2,??Formula (1) wherein, in Formula (1), M represents K or Na, x represents 1 or 2, and y represents an integer of 1 to 5.

Abstract: The present invention provides an ink set including an ink composition and a maintenance liquid that removes from a head nozzle surface a substance that is derived from the ink composition and that adheres to the head nozzle surface, the ink composition including a pigment coated with a water-insoluble polymer formed by copolymerizing a monomer mixture including a styrene macromer; polymer particles; a water-soluble organic solvent; and water.

Abstract: The present invention provides a maintenance liquid for inkjet recording including at least water, an organic solvent, a basic compound and an acidic compound, and having pH of from 6.0 to 8.5.

Abstract: Disclosed is an ink composition with excellent adhesiveness of an image on a recording medium and recoverability after being left for a period. The ink composition of the present invention contains coloring particles that include a quinacridone solid solution pigment including two or more types of quinacridone-based compounds, a synergist including a basic group, and a high-molecular weight vinyl polymer, a water-soluble polymerizable compound, a polymerization initiator and water.

Abstract: An ink composition having excellent ink stability over time and image adhesion to a recording medium is provided. The ink composition of the present invention includes: cross-linked particles containing a quinacridone solid solution pigment including at least two types of quinacridone-based compound; a water-soluble polymerizable compound; a polymerization initiator; and water.

Abstract: The present invention provides an image forming method including jetting an ink composition containing a pigment, a volatile water-soluble organic solvent, polymer particles and water, from a heated nozzle plate of an inkjet head onto a recording medium; and applying a maintenance liquid on a nozzle surface of the nozzle plate after jetting.

Abstract: The invention provides an ink set having at least an ink composition and a maintenance liquid. The ink composition comprises a pigment (i). The maintenance liquid comprises one or more solvents (ii) having a solubility parameter value of 27.5 or less. The content of the one or more solvents (ii) is 50 weight % or more with respect to a total solvent content of the maintenance liquid. The invention further provides a method of forming an image using the ink set including at least applying, with a liquid applying device, the ink composition to a recording medium, and applying a maintenance liquid to the liquid applying device.

Abstract: The present invention provides a maintenance liquid for ink jetting, the maintenance liquid including: water and an organic solvent having an ether bond, a content of the organic solvent being from 15% by mass to 40% by mass with respect to maintenance liquid, and a concentration of peroxide in the maintenance liquid being 0.1 mmol/L or lower; a method of manufacturing the above maintenance liquid for ink jetting, the method including a process for mixing water and the organic solvent having an ether bond; and a process for purifying by distilling in advance the organic solvent having an ether bond that is used in the mixing; an ink set for ink jetting including: the maintenance liquid for ink jetting and an aqueous ink composition having a pH of from 7.0 to 10.0; and an image forming method that uses the ink set for ink jetting.

Abstract: The present invention provides a maintenance liquid for inkjet recording including at least water, an organic solvent, a basic compound and an acidic compound, and having pH of from 6.0 to 8.5.

Abstract: The invention provides a maintenance liquid, containing water, a water-soluble organic solvent, and at least one of a water-soluble silicate represented by Formula (1) or colloidal silica: xM2O.ySiO2,??Formula (1) wherein, in Formula (1), M represents K or Na, x represents 1 or 2, and y represents an integer of 1 to 5.