This injection mold is purpose-built for manufacturing flip-top caps commonly used on shampoo bottles, body wash containers, ketchup bottles, and industrial chemical packaging. The mold incorporates an advanced living hinge design that ensures the hinge remains flexible and durable for over 10,000 open-close cycles without cracking. The complex geometry — including the base cap, the flip lid, the hinge strap, and the snap-fit locking mechanism — is produced in a single shot using polypropylene (PP) or polyethylene (PE). The mold is constructed from Stavax ESR or DIN 1.2083 stainless steel, hardened to 48–52 HRC, with mirror-polished cavity surfaces (SPI-A2) to ensure easy demolding of the delicate hinge area without sticking. A hot runner system with individually controlled valve gates ensures precise filling of the thin hinge section without overpacking or short shots. Automatic unscrewing is handled by a rack-and-pinion or hydraulic unscrewing mechanism for caps requiring threads, while the lid is ejected using sleeve ejectors to avoid visible witness marks. Cycle time typically ranges from 8 to 14 seconds depending on part weight and cavity count. Each mold is tested with your specified resin on our 250-ton injection press before shipping, and we provide complete setup parameters including injection speed profile, holding pressure, and cooling time.