Coinjection

Co-injection is a polymer injection technology in which different polymers are injected into the same mold. This specialized process can be used to improve part performance and cost while minimizing cycle time and production volume. Co-injection can be used to extend shelf life, improve production efficiencies, and allow for greater design flexibility depending on the materials used and the application.
Reasons for using co-injection are:
Despite these advantages, co-injection requires machinery that is more expensive and difficult to maintain than standard single injection machines. The coinjection process also has difficulty with complex geometric shapes.
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