Injection-Blow Molding Multi-Layer Barrier Bottles
Kortec hot-runner technology and an auxiliary injector convert a standard machine to three-layer co-injection blow molding.
Milacron is exhibiting a Uniloy IBS 85 (81 tons) injection-blow machine that is available in electric, hydraulic, and hybrid versions. The news here is that this machine is equipped to mold three-layer barrier containers. Up to now, Milacron’s Kortec co-injection technology has been used mainly on injection molding machines to produce barrier preforms and the Klear Can for food. But Milacron is using an injection-blow machine to illustrate its new Kortec Connect program for retrofitting existing injection machines to perform barrier co-injection.
The IBS 85 is outfitted with a Kortec co-injection hot-runner system and a Mold-Masters E-Multi electric servo-driven secondary injection unit to deliver the barrier layer. The IBS 85 is molding a 7.5-g pill bottles from a four-cavity tool in a 12-sec cycle.
Taking coextrusion blow molded bottles beyond six layers while maintaining conventional wall thicknesses is at the core of a new micro-layer approach developed by Dow.
Dealing effectively with regrind has been a tough challenge for most blow molders ever since the process was invented.
Careful choices of machines, tools and operators are critical to tame the process to produce high-quality bottles consistently.