Double Shot injection molding which some people call 2K injection molding or two shot injection molding, is the process of molding two or more different plastic materials into one part at one time. One important element of double shot injection molding is the two materials must be compatible with each other and designed to overmold.

Otherwise, the product doesn’t hold up during the procedure, sometimes overmolding is also a single type of 2k injection molding, but a lot of the materials that are designed for over molding may not be appropriate for this two-shot process. This is because one material requires a larger amount of cycle time to produce than the other material. Again, compatibility of materials is key.

Produce a single part with different regional plastic materials or mold a single part with multiple independent colours. Applications range from simple household items like powder tools or toothbrush etc.

Type of Double Injection Molding

Double injection molding is a process that involves injecting two different materials into a single mold to create a finished product with two or more colors, textures, or properties. There are several types of double injection molding, including:

1. Sequential Injection Molding: In this process, one material is injected into the mold, and then the second material is injected into the first material after it has partially solidified. This method is suitable for creating products with different colors or textures.
2. Co-injection Molding: Co-injection molding involves injecting two materials simultaneously into the same plastic injection mold. The materials are injected through different nozzles and meet in the mold cavity, where they bond together to form a single part. This process is used to create products with a core and an outer layer, such as a bottle with a soft, flexible grip and a rigid base.
3. Sandwich Molding: In sandwich molding, the two materials are injected into the same mold cavity, but are separated by a third material, called the “core.” This process is used to create products with a foam or honeycomb core, such as a lightweight composite panel for the aerospace industry.
4. Overmolding: Overmolding involves molding one material over another, such as molding a rubber grip onto a plastic handle. This process is used to create products with a soft-touch feel or to add additional functionality to a product, such as an anti-slip grip.

We offer two-shot injection molding service and over molding service to the world, we have parallel 2k injection molding machines and the 90-degree double injection molding machine, if you need any type of double injection molding parts or overmolding parts contact with us, we will offer you the best quality.

If you want to know more information about two shot molding? you can go to two-shot molding page to take a look.