In the field of medical device manufacturing, liquid silicone rubber injection molding (LIM) is a process that has several advantages over other methods. The technology can reduce product strength and weight, while being more cost-effective than some alternatives, and still producing the final product within the parameters set by equipment and regulators.

The Molding Process of Medical Device Manufacturing

There are many kinds of molding processes for medical device manufacturing, including thermoplastic, micro molding, compression molding, transfer molding, etc. Choosing the right molding process is very important in creating a successful and high-quality final product. Here are some common options:

• Transfer Molding

By transfer molding, hydraulic plungers push rubber through the runner and gate into specific cavities. The benefit of transfer molding is that it requires very little setup time, and it is very useful for both small and high-volume production. Contract manufacturing organizations (CMOs) can also use the process for the secondary molding of metal and plastic inserts.

• Compression molding

Compression molding involves the preparation of organosilicon outside of the molding process. Position the shot in each mold cavity, seal with the top, then compress to ensure access to all areas of the mold. The compression molding process is suitable for large geometric parts and encapsulation molding applications.

Silicone Medical Parts

• Micro-molding

This is a form of LIM and is suitable for components requiring injections of less than 6 grams. This applies to products that require strict tolerances and strict flash requirements. It is commonly used in parts of minimally invasive surgical tools, valves, and seals. Because of its precise tools, micro-molding is also used in micro-sensory and microfluid products.

• Silicone and Metal Bonding/Insert Molding

Silicone rubber is bonded to the primer substrate by insert forming and cladding forming. The challenge here is to ensure that the inserts remain in the correct position throughout the molding cycle. Inserts are pretreated to produce maximum bonding strength and durability.

• Thermoplastic Injection Molding

Thermoplastic injection molding is a reversible molding process in which plastic particles are melted, forced into a mold to take on their final shape, and then quickly cooled and hardened. This method is ideal for creating parts with excellent surfaces and finishes. Precise, fully functional components and parts can be manufactured for prototype and full-scale production runs.

• Insert/Wrap Molding

A thermoplastic material molded around extruded, metal inserts, or other functional parts that have been placed in plastic injection molds. The advantage of using this technique is that it can create durable integrated components at a lower assembly cost while maintaining quality.

• Liquid Injection Molding (LIM)

Liquid injection molding (LIM), uses silicone rubber or liquid silicone rubber (LSR) to make highly durable silicone parts that can withstand extreme conditions. Liquid injection molding involves injecting liquid silicone rubber or rubber into a prefabricated mold to form a device or part, which is then heated to cure and solidify the shape.

The Benefits of Silicone Liquid Injection Molding

Liquid injection molding using liquid silicone rubber offers numerous advantages to medical device manufacturers, making it one of the most popular solutions for manufacturing rubber parts. Here are some benefits: