An ink set according to the present disclosure includes: a treatment liquid containing an aggregating agent; a deep ink composition; and a light ink composition, the ink compositions containing colorants, belonging to the same color system, and each being a water-based ink jet ink, the light ink composition contains an organic solvent which is a condensate of an alkanediol having 2 or 3 carbon atoms and which has two hydroxy groups, and the deep ink composition contains an organic solvent which is an alkanediol having 2 to 4 carbon atoms.

A formulation system usable in additive manufacturing of a three-dimensional object that comprises, in at least a portion thereof, a cyanate ester-containing polymeric network, and additive manufacturing processes employing the formulation system are provided. Also provided are objects obtainable by the additive manufacturing and kits containing the formulation system. The formulation system includes a first modeling material formulation which includes a first curable material which is a thermally-curable cyanate ester and a second modeling material formulation which comprises an activating agent for promoting polymerization of the cyanate ester and is devoid of the first curable material, and further includes a second curable material which is different from the first curable material, and optionally an agent for promoting hardening of the second curable material.

An object of the present invention is to provide an ink composition for manufacturing an organic semiconductor device, the ink composition allowing an organic semiconductor material with a rigid main chain into an ink having an optimal solute concentration for a single-crystal formation process. The present invention provides an ink composition for manufacturing an organic semiconductor device, the ink composition including at least one solvent selected from Naphthalene Compound (A) and at least one solute. The isomer content of Naphthalene Compound (A) is preferably 2% or less in terms of a percentage for peak area with Naphthalene Compound (A) being 100% in gas chromatography. Naphthalene Compound (A): a compound represented by Formula (a), where in Formula (a), R is as defined in the description.

An object of the present invention is to provide an ink composition for manufacturing an organic semiconductor device, the ink composition allowing an organic semiconductor material with a rigid main chain into an ink having an optimal solute concentration for a single-crystal formation process. The present invention provides an ink composition for manufacturing an organic semiconductor device, the ink composition including at least one solvent selected from Naphthalene Compound (A) and at least one solute. The isomer content of Naphthalene Compound (A) is preferably 2% or less in terms of a percentage for peak area with Naphthalene Compound (A) being 100% in gas chromatography. Naphthalene Compound (A): a compound represented by Formula (a), where in Formula (a), R is as defined in the description.

A method of printing a stealth white image includes applying a stealth ink containing a red coloring material that emits visible light at exposure to ultraviolet radiation and a green coloring material that emits visible light at exposure to ultraviolet radiation to a substrate which contains a fluorescent brightener to form the stealth white image thereon, wherein the stealth white image demonstrates an a* value of from −2.0 to 2.0 and a b* value of from −10.0 to 0 at exposure to ultraviolet radiation having a wavelength of 370 nm according to CIE 1976 L*a*b* colorimetric system.

A method of printing a stealth white image includes applying a stealth ink containing a red coloring material that emits visible light at exposure to ultraviolet radiation and a green coloring material that emits visible light at exposure to ultraviolet radiation to a substrate which contains a fluorescent brightener to form the stealth white image thereon, wherein the stealth white image demonstrates an a* value of from −2.0 to 2.0 and a b* value of from −10.0 to 0 at exposure to ultraviolet radiation having a wavelength of 370 nm according to CIE 1976 L*a*b* colorimetric system.

An image forming method includes a processing fluid applying step and an ink applying step. The processing fluid applying step involves applying a processing fluid containing a multivalent metal salt, a resin T.sub.A, a resin T.sub.B different from the resin T.sub.A, and a silicone-based surfactant to a non-permeating base material by an inkjet method, where the processing fluid is free of an organic solvent having a boiling point of 200° C. or higher at normal pressure. The ink applying step involves applying an ink containing a coloring material, an organic solvent, and a resin onto the processing fluid.

An image forming method includes a processing fluid applying step and an ink applying step. The processing fluid applying step involves applying a processing fluid containing a multivalent metal salt, a resin T.sub.A, a resin T.sub.B different from the resin T.sub.A, and a silicone-based surfactant to a non-permeating base material by an inkjet method, where the processing fluid is free of an organic solvent having a boiling point of 200° C. or higher at normal pressure. The ink applying step involves applying an ink containing a coloring material, an organic solvent, and a resin onto the processing fluid.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.