Liquid Silicone Rubber, as the name suggests, is liquid enough to be mixed in a static chamber: Inside two compounds are mixed together in equal parts with a third platinum catalyst and any desired color pigment. The final mixed liquid rubber compound is then pumped through tubes into a mold where the low viscosity of the liquid silicone rubber delivers a perfect seal, thereby creating a final part without any burrs. Once in the mold, the liquid silicone rubber is heated and hardened in a process known as vulcanization.
Like any standard injection molding tool, a liquid silicone rubber mold is made via CNC machining a heat resistant, durable, metal (steel or aluminum) to create a mold able to consistently withstand the molding process. Once cut: form, fit and function are signed off, before the tool is polished as per customer surface finish specifications. There are a wide range of surface finishes available at HCBluestone. When it comes to manufactured parts or products: if it’s possible, it’s possible in the Pearl River Delta (PRD).
Liquid Silicone Rubber is a thermosetting polymer and as such the final part remains in its final molded state. It can’t be melted again and remolded, like a thermoplastic material. Parts are checked and batched as they come off the injection molding machine. From there, according to the project requirements, they’re moved on either to product assembly, or straight to the packaging department for quality control, before shipping.