Abstract: Provided is a liquid crosslinking agent in which liquid life (pot life) as an undiluted solution is sufficiently long and excellent coating properties are exhibited when used. A liquid crosslinking agent containing an epoxy compound and an emulsifier, in which a content of water is 39% by mass or less with respect to a total amount of a liquid, and a contact angle with respect to a poly(ethylene-methacrylic acid) film when preparing an aqueous dispersion in which a concentration of a non-volatile component is 15% by mass is 42.0° or less. It is preferable that the epoxy compound has two or more epoxy groups in molecules, and it is preferable that the emulsifier is a nonionic surfactant. Provided is a coating method of a liquid crosslinking agent including diluting the liquid crosslinking agent with water to be used for coating.

Abstract: Provided are a method for manufacturing a rubber composition, which method can give a rubber composition provided with excellent reinforcement properties by improving the dispersibility of fibers in a rubber component when the fibers are added to the rubber, a rubber composition obtained using this method, a vulcanized rubber, and a tire. The method is a method for manufacturing a rubber composition comprising short fibers, comprising a dispersion preparation step for preparing a short fiber dispersion by adding the short fibers into a liquid, a mixed dispersion preparation step for preparing a mixed dispersion by adding at least one dispersant selected from the group consisting of carbon black and inorganic compounds into the short fiber dispersion, a mixing step for mixing the mixed dispersion and rubber latex to prepare a rubber-short fiber mixed solution, and a drying step for drying the rubber-short fiber mixed solution to give a rubber composition.

Abstract: Provided are a method for manufacturing a rubber composition, which method can give a rubber composition provided with excellent reinforcement properties by improving the dispersibility of fibers in a rubber component when the fibers are added to the rubber, a rubber composition obtained using this method, a vulcanized rubber, and a tire. The method is a method for manufacturing a rubber composition comprising short fibers, comprising a dispersion preparation step for preparing a short fiber dispersion by adding the short fibers into a liquid, a mixed dispersion preparation step for preparing a mixed dispersion by adding at least one dispersant selected from the group consisting of carbon black and inorganic compounds into the short fiber dispersion, a mixing step for mixing the mixed dispersion and rubber latex to prepare a rubber-short fiber mixed solution, and a drying step for drying the rubber-short fiber mixed solution to give a rubber composition.