Coinjection Blow Molding Systems Introduced for Medical Applications

Originally Published MPMN January 2005

Although it is one of the leading suppliers of turnkey coinjection systems in the world, Kortec Inc. (Ispwich, MA; www.kortec.com) has not been on the med-tech industry's radar. Until now. The firm recently teamed with Uniloy Milacron (Manchester, MI; www.milacron.com) to develop coinjection blow molding systems specifically for healthcare applications. The first UMIB 85.S machine was recently sold to a medical device OEM.

The project had its genesis in a "what-if" question posed by a customer.

Kortec is well regarded for its three-layer preform technology that combines PET with barrier materials. The multilayer construction offers clarity and strength while maximizing a product's shelf life. Intrigued by the possibilities, a medical device manufacturer wondered if the technology could lend itself to smaller cavity molds and to the use of resins other than PET. "That was not possible with the existing commercially available equipment," says Douglas Svik, new applications manager at Uniloy Milacron. "So Kortec turned to us to supply injection molding capability for their coinjection technology."

Kortec's coinjection system is integrated into Uniloy Milacron's injection blow molding machines. The true reciprocating-screw injection unit and closed-loop control of independent fill and recovery pressures meshed well with Kortec's technology, according to Kortec vice president of marketing and sales John Kermet.

Kortec typically partners with clients to provide turnkey application-specific systems. After consultation with customers, the units are designed and built at the Kortec plant, where the cell is "proved out" before being disassembled and shipped to the client. There it is reassembled and put into production. Kortec manages the entire project and provides customer training and technical support.

The initial medical application involves molding a multilayer container that sandwiches polyamide between two layers of polycarbonate. The product is transparent and virtually unbreakable. In the past, "much of the industry has extrusion blow molded these types of containers," says Svik. "But you can't get the precise tight-tolerance finish that you can with injection molding. This development by Kortec has taken what was achievable only by means of a highly proprietary process and made it a commercially available technology," Svik adds.

The systems are suited for molding an array of bottles, vials, and single-use products. "Any number of medical products that require the use of a barrier material are potential applications," notes Svik. The first unit produced for a medical device company has four cavities, but higher cavitation units are being readied.

Copyright ©2005 Medical Product Manufacturing News