Abstract: Provided is an injection molding system capable of improving usability for a user. The injection molding system determines a combination of a mold and an injection molding machine and a specific molding condition specific to the combination of the mold and the injection molding machine, and outputs the determined specific molding condition in a predetermined form for manual input to the injection molding machine.

Abstract: A method for producing a rubber composition containing by weight 5 to 95 parts of natural rubber (NR), 95 to 5 parts of chloroprene rubber (CR), and 20 to 90 parts of carbon black (CB), using a kneading machine, includes a first step of producing a master batch (M1) containing NR and CB; a second step of producing a master batch (M2) containing CR and CB, and a third step of mixing the M1 and M2 with each other to produce a master batch (M3) containing NR, CR, and CB, wherein the amount of CB contained in the M2 is from 40 to 70% by weight relative to the total amount of CB in the rubber composition, and when the M2 is discharged from the kneading machine after the second step, the actually measured temperature of the rubber composition is from 100 to 130° C.

Abstract: A method for producing a rubber composition containing by weight 5 to 95 parts of natural rubber (NR), 95 to 5 parts of chloroprene rubber (CR), and 20 to 90 parts of carbon black (CB), using a kneading machine, includes a first step of producing a master batch (M1) containing NR and CB; a second step of producing a master batch (M2) containing CR and CB, and a third step of mixing the M1 and M2 with each other to produce a master batch (M3) containing NR, CR, and CB, wherein the amount of CB contained in the M2 is from 40 to 70% by weight relative to the total amount of CB in the rubber composition, and when the M2 is discharged from the kneading machine after the second step, the actually measured temperature of the rubber composition is from 100 to 130° C.