Abstract: When kneading kneading materials that include raw rubber and carbon black in a closed-type rubber kneader, the extent of the kneading efficiency of the closed-type rubber kneader is evaluated in accordance with the magnitude of the evaluation index calculated from unit work/total amount of shear by calculating an evaluation index calculated by a calculation device based on a total amount of shear obtained by integrating the shear velocity applied to the kneading materials by a rotor that is being driven to rotate by the rotor drive unit of the kneader over the kneading time, and a unit work obtained by dividing the integrated power obtained by integrating the instantaneous power of the rotor drive unit over the kneading time by the mass of the kneading materials.

Abstract: To provide a rubber composition having excellent durability against external environment, and a vulcanization rubber product and a hose using the same. The rubber composition of the present technology is a rubber composition comprising: a rubber component (A), a water repellent (B), and hydrotalcite (C). In the rubber composition, the rubber component (A) comprises CR, SBR, or both CR and SBR; and the water repellent (B) comprises one or more types of ultra high molecular weight polyethylene powders or fatty acid amide compounds. The total content of the components of the water repellent (B) is from 2 parts by mass to 30 parts by mass per 100 parts by mass of the rubber component (A); and the content of the hydrotalcite (C) is from 2 parts by mass to 20 parts by mass per 100 parts by mass of the rubber component (A).

Abstract: The system includes: a closed-type rubber kneader that kneads kneading materials that include raw rubber and carbon black; a rotation meter of a rotor; a power meter that measures the instantaneous power required to drive the rotation of the rotor; and a calculation device to which the measurement data is input. The calculation device calculates an evaluation index that evaluates the kneading efficiency of the kneader based on the total amount of shear calculated by integrating the shear velocity applied to the kneading materials by the rotor over the kneading time, and a unit work calculated by dividing the integrated power obtained by integrating the instantaneous power over the kneading time by the mass of the kneading materials.

Abstract: The system includes: a closed-type rubber kneader that kneads kneading materials that include raw rubber and carbon black; a rotation meter of a rotor; a power meter that measures the instantaneous power required to drive the rotation of the rotor; and a calculation device to which the measurement data is input. The calculation device calculates an evaluation index that evaluates the kneading efficiency of the kneader based on the total amount of shear calculated by integrating the shear velocity applied to the kneading materials by the rotor over the kneading time, and a unit work calculated by dividing the integrated power obtained by integrating the instantaneous power over the kneading time by the mass of the kneading materials.

Abstract: When kneading kneading materials that include raw rubber and carbon black in a closed-type rubber kneader, the extent of the kneading efficiency of the closed-type rubber kneader is evaluated in accordance with the magnitude of the evaluation index calculated from unit work/total amount of shear by calculating an evaluation index calculated by a calculation device based on a total amount of shear obtained by integrating the shear velocity applied to the kneading materials by a rotor that is being driven to rotate by the rotor drive unit of the kneader over the kneading time, and a unit work obtained by dividing the integrated power obtained by integrating the instantaneous power of the rotor drive unit over the kneading time by the mass of the kneading materials.

Abstract: The present technology includes an inner tube, the inner tube having a resin layer as an innermost layer and a rubber layer adjacent to the innermost layer. A material used in the resin layer is a resin composition that includes a resin including at least an ionomer containing a metal carboxylate, and a material used in the rubber layer is a rubber composition that includes a rubber including at least an epoxidized rubber.

Abstract: A hose for transporting refrigerant includes an inner tube layer having a gas barrier layer and a rubber layer adjacent to the outer surface of the gas barrier layer. The gas barrier layer is formed using a thermoplastic resin composition comprising a polyamide resin and a modified rubber having an acid anhydride group or an epoxy group, the modified rubber being obtained by modifying a modified raw rubber having an acid anhydride group or an epoxy group with a hydrogen bond-forming compound having a functional group which reacts with the acid anhydride group or the epoxy group and a functional group which is able to form a hydrogen bond with an amide bond or a hydroxyl group. The rubber layer is formed using a rubber composition comprising from 1 to 15 parts by mass of an alkylphenol-formaldehyde resin per 100 parts by mass of a raw rubber.

Abstract: A hose for transporting refrigerant of this invention is a hose comprising an inner tube layer including a gas barrier layer and a rubber layer adjacent to an outer surface of the gas barrier layer. The rubber layer comprises a rubber composition comprising from 1 to 15 parts by mass of an alkylphenol-formaldehyde resin and from 1 to 8 parts by mass of a hydrotalcite per 100 parts by mass of a raw rubber. The raw rubber comprises at least one selected from the group consisting of a BIMS and a butyl rubber and/or a halogenated butyl rubber, which is a copolymer rubber. The gas barrier layer comprises a polyamide resin composition comprising a modified polyamide obtained by blending a polyamide and a carboxyl group-containing modified polyolefin. The hose for transporting refrigerant of this invention has superior adhesion between the gas barrier layer and the rubber layer.

Abstract: A hose for transporting refrigerant includes an inner tube layer having a gas barrier layer and a rubber layer adjacent to the outer surface of the gas barrier layer. The gas barrier layer is formed using a thermoplastic resin composition comprising a polyamide resin and a modified rubber having an acid anhydride group or an epoxy group, the modified rubber being obtained by modifying a modified raw rubber having an acid anhydride group or an epoxy group with a hydrogen bond-forming compound having a functional group which reacts with the acid anhydride group or the epoxy group and a functional group which is able to form a hydrogen bond with an amide bond or a hydroxyl group. The rubber layer is formed using a rubber composition comprising from 1 to 15 parts by mass of an alkylphenol-formaldehyde resin per 100 parts by mass of a raw rubber.

Abstract: A hose for transporting refrigerant of this invention is a hose comprising an inner tube layer including a gas barrier layer and a rubber layer adjacent to an outer surface of the gas barrier layer. The rubber layer comprises a rubber composition comprising from 1 to 15 parts by mass of an alkylphenol-formaldehyde resin and from 1 to 8 parts by mass of a hydrotalcite per 100 parts by mass of a raw rubber. The raw rubber comprises at least one selected from the group consisting of a BIMS and a butyl rubber and/or a halogenated butyl rubber, which is a copolymer rubber. The gas barrier layer comprises a polyamide resin composition comprising a modified polyamide obtained by blending a polyamide and a carboxyl group-containing modified polyolefin. The hose for transporting refrigerant of this invention has superior adhesion between the gas barrier layer and the rubber layer.