In the biaxially oriented polypropylene (BOPP) field, size and volume generally rule the day. BI-AX International Inc. produced millions of pounds of BOPP film a year for a wide range of commodity products.
Based BOPP producer started up in 1988, BI-AX International used to play in that high-volume game. Between its 220,000 ft² plant and a 35,000 ft² facility, the company runs three BOPP lines—3, 5 and 8 meters wide—with a capacity of 40 million lb/year. But instead of pumping up the volume, BI-AX has shifted toward higher-value products where its expertise in processing and R&D are bearing fruit.
A family-owned and operated business since it opened its doors, the firm actually started out making polyethylene drainage tubes in 1976, then 10 years later expanded into PE sheet used to make fences around construction sites. Then, after buying a used line from Mobil that it had intended to use for the fencing business, the processor was approached by a large customer about the shortage of BOPP, and decided to enter the film business.
BI-AX keeps its BOPP lines busy doing a lot of research, product development, and even toll processing for other film producers. The company works collaboratively with other film processors on a regular basis, using production equipment to scale up what they might have done in their labs. “It is truly collaborative, because sometimes we simply make product from their recipe, sometimes we tweak it. They might, for example, want a product that’s tacky today but not tomorrow. What we have found over the years is that customers usually know what they want, but not what they need to get there,” said Tom Inglis, BI-AX’s general manager and part of the ownership group. Toll manufacturing can be a volatile business. Projects may start slow, then suddenly pick up to the point where you have a hard time keeping up. And then at some point, most of the film producers will ramp up their own production capabilities. So then you’re less busy. The processor also does toll orientation for processors that don’t have their own machine-direction orientation (MDO) equipment.
BI-AX’s core business is in two areas. One is BOPP for high-end medical uses. It produces a breathable, PP-based microporous film tradenamed Aptra under an exclusive contract with RKW Danafilms Inc. Based in Westborough, Mass., RKW Danafilms is a wholly-owned subsidiary of RKW SE, Europe’s largest film producer (based in Germany). The Aptra film is then sold to Kappler Inc., Guntersville, Ala., which laminates it to a nonwoven fabric to create protective garments used to protect hospital workers and others from infectious diseases such as H1N1 virus (aka “swine flu”) and Ebola. The Aptra line consists of two products: Aptra Classic is a high-performance breathable film used for disposable clothing in biohazardous environments. It passes ASTM standard F1671 for Viral Penetration and F 1670 for Blood-Borne Pathogens. The film is also used for packaging high-end analytical equipment. Another Aptra product—designated UV8—targets a much different market: It’s used as a waterproof, breathable roofing material, primarily in Europe.
BI-AX typically runs three extruders on two of its lines. Aptra film is produced from 40 to 50 microns thick on BI-AX’s 3- or 5-meter lines."The material we produce is extremely soft with a very high moisture-vapor transmission rate,” Inglis states. The polymer science behind it creates micro-voids within the film where water vapor—but not liquid—can pass through. This feature is achieved partly as a result of the manner in which the Aptra film is produced.
Film tolerances are kept tight on both Aptra and Evlon product lines by thickness gauges that are looped to dies that can be adjusted on the fly.
All film lines are equipped with a supervisory control and data-acquisition system that BI-AX updates on a regular basis. The firm also uses on-line gauge control and adjustable-lip dies to correct variations on the fly. BI-AX worked very early with NatureWorks LLC, Minnetonka, Minn., on developing applications for the materials company’s Ingeo PLA biopolymer. BI-AX produces a product tradenamed Evlon that is used in compostable packaging for snacks, produce, candy, and more. The products made by BI-AX International are coextrusions, so that add to the complexity of making PLA film. The Evlon line is run from 15 microns all the way up to 13 mils, which technically is considered sheet.