LSR Injection Overmolding

LSR overmolding is a process of molding LSR over another component. This method lets you mold LSR right onto plastic, metal, or other substrates, creating a strong bond between the materials. Liquid silicone overmolding makes the final product more durable, flexible, and functional, which makes it perfect for industries that need precision and complex designs.

The advantages of liquid silicone overmolding?

LSR（Liquid silicone rubber）material
LSR overmolding offers numerous benefits due to the material’s exceptional properties, such as high transparency, tear strength, thermal stability, and aging resistance.
Strong Inclusiveness
This process allows for overmolding onto various substrates, including metal and plastic parts.
Automated Process
With liquid silicone injection molding, the second step in the process involves automatic injection and precision molding, which ensures excellent adhesion and minimizes material waste.
Cost and time savings
Molding silicone rubber directly onto a metal or plastic substrate means you don't have to go through the whole secondary post-molding assembly process, which saves costs and time on assembly.
Quality
The accuracy and control in a stable overmolding process guarantees precision, high-quality, securely bonded parts and eliminates the risk of seal displacement.
As a result, many products now rely on liquid silicone molding for high-quality, efficient production. This is why leading silicone injection molding manufacturers are adopting this process.

How it works?

Step 1
Keep the Surface Clean and Dry For effective LSR overmolding, the substrate (plastic, metal, or other substrates) must be clean and dry. Contaminants like oils or mold release agents can disrupt bonding during the liquid silicone injection molding process. However, LSR 2-shot overmolding usually avoids this issue.
Step 2
Heating the Substrates in silicone overmolding Proper heating of the substrate is crucial for strong bonding during the silicone overmolding. The ideal temperature range is between 120 and 150°C.
Step 3
Good Design for Mechanical Bonding in overmolding, loops and features allow liquid silicone to lock into the substrate, enhancing mechanical bonding during liquid silicone injection molding.
Step 4
Surface Treatment for Better Bonding, primers can help improve bonding between liquid silicone and the substrate. However, for medical devices, plasma surface treatment is often preferred because it avoids introducing non-biocompatible substances.

Benefits of Liquid silicon rubber for Your Project？

What you should notice when operating LSR overmolding？

1.To determine the high temperature resistance of their own encapsulated insert material, to be around 130 degrees, otherwise the product will be deformed or to sacrifice productivity!
2.To choose the appropriate material for the insert coating to paint the bottom, many people just do not choose the right coating leads to bonding is not strong! By focusing on these aspects, manufacturers can improve bond strength, avoid deformation, save The cost, and enhance overall production efficiency, leading to more reliable and durable final products.

Why Choose TYM？

Working with TYM, you can realize shorter time-to-market, reduced management risk, and better cost control, and get you there SMOOTHLY! TYM is the expert in silicone rubber overmolding. We have produced billions of custom silicone rubber overmolded parts for customers all over the world. We specialize in delivering exceptional quality across large volume orders. We customize our molding process and QA procedures to meet your specific requirements. We can make any aspect of the silicone overmolding/insert plastic molding process fit your specifications.
Contact TYM today to learn more about our OEM&ODM solutions.

Industries & Applications

LSR injection molding provides effective solutions across vaious industries, leveraging the unique properies of liquid silicone rubber to enhance product quality and performance.