Injection blow molding (IBM) and injection stretch blow molding (ISBM) are processes used for plastic materials. They allow the molding of empty parts (bottles for instance), and form the sides of the product that can resist internal and external pressure.

This type of processes implies forming an initial shape using melted plastic (IM). These preforms are then heated in a blow-molding machine (generally using infrared lamps) above a glass transition temperature. The blowing process will then be applied (injecting high pressured air into the bottle). These initial shapes will then be stretched (ISBM) or not (IBM) by pressing against the sides of a cold mold. The content is then left to cool down and when it is sufficiently cold, it is removed from the mold.