Foster Corp. Adds Plastics Extrusion Capabilities

Putnam, Conn.-based medical plastics manufacturer Foster Corporation has added extrusion compounding capacity for custom pre-colored polymers used in Class I medical applications. Classes are designated by the U.S. Food and Drug Administration according to how much control a device needs to be safe, with Class I requiring the least regulatory control. The new extrusion line is designed to optimize pigment dispersion of colors and polymers that are challenging to manipulate, and to reduce compounding costs. The equipment was designed to serve high-volume medical applications where color is critical and cost is important, such as custom colored polymers for bandage or packaging film.

The line includes twin-screw extrusion capable of volume output in excess of 1,000 pounds per hour (454 kilograms per hour). Traditional strand cutting and underwater pelletizing are available, the latter for low-durometer materials such as urethanes and thermoplastic elastomers.


Traditionally, polymers produced in high volume are colored by blending concentrates from a master-batch of pigment with natural polymers prior to manufacturing. Another method is pre-coloring polymers using high-throughput, single screw extrusion equipment. Both methods can work well, but in some Class I devices, pigment dispersion proves difficult because some of the polymers in question require high color saturation and/or have very thin walls. Such delicate components require small molding or extrusion equipment, and that inherently limits pigment dispersion capabilities.


“Foster has developed an expertise in the dispersion of additives in polymers for thin wall parts,” said Christine Howe, director of manufacturing for Foster Corporation. “We have designed this new larger line to provide the same quality and consistency for Class I devices with demanding color requirements. These applications generally consume higher volumes and are under increased pressure to reduce costs.”