Injection blow molding is used for the production of hollow objects in large quantities. The polymer is injection molded onto a core pin; then the core pin is rotated to a blow molding station to be inflated and cooled. There are three steps in this process: injection, blowing and ejection.

In Injection Stretch Blow Molding, the plastic is first molded into the form using the Injection Blow Molding Process. However, in this process, the preformed molds are heated, then blown using high pressure air into bottles using metal blow molds. The stretching of some polymers results in strain hardening of the resin.

Applications: Thin and thick walled bottles and jars