Overmolding: Perform secondary molding on a layer of plastic to enhance functionality or decoration. Suitable for phone cases, tool handles, and electronic device buttons. As a plastic overmolding manufacturer, we specialize in producing overmolded parts for various applications.

Design product as needs

• Design the product structure with two materials or colors based on functional and aesthetic requirements.
• Ensure the compatibility of the two materials (such as chemical or physical bonding) and the molding sequence.

Design & manufacture mold

• Use a multi-cavity mold (divided into the first injection cavity and the second injection cavity) to ensure the accuracy of the two-step molding process.
• Design a rotating mechanism or slide mechanism to move the semi-finished product to the second cavity after the first molding.
• Design the gate and cooling system to accommodate the molding requirements of different materials.

Materials preparation

• Choose two suitable plastic materials (such as hard plastic and soft plastic, or two different colored materials).
• Dry the materials to ensure the stability of the injection molding process and the quality of the product.

(Base) 1st Injection Molding

• Inject the first plastic material into the first cavity of the mold to form the base part of the product (such as the hard structure).
• After molding, the product is either kept in the mold or moved to the second cavity by a rotating mechanism.

(Decoration) 2nd Injection Molding

• Move the semi-finished product from the first molding to the second cavity, accurately position it, and then inject the second plastic material.
• The second material is typically used for decorative, functional, or soft components (such as surface layers, sealing gaskets, or anti-slip structures).

Cooling Solidifying

• The two materials cool and solidify in the mold, forming an integrated structure.
• The cooling time depends on the materials and the product structure.

Mold ejection

• Use ejector pins or an ejector plate to remove the finished product from the mold.
• Special care should be taken when removing the product to avoid damaging the bonding areas of the product.

Post-processing Inspection

• Trim the product's flash and any excess parts; secondary processing may be performed if necessary.
• Check the quality, qualified products are packaged and stored, while defective ones are reworked or scrapped.