Breaking the Mold

Bemis Manufacturing, Sheboygan Falls, Wis., has been a component partner with OEMs as well as a manufacturer of commercial products, including toilet seats and medical devices, for more than 100 years.

Bemis’s involvement as a plastic consumer started in the early 1960s when it began using injection molding along with wood compression. This transition occurred during a time when wood was going out of favor in manufacturing, according to Tom Reinemann, director of material management, Bemis Contract Group. "There were fewer things being made out of wood," Reinemann says.

Bemis also saw this shift as an opportunity to make some product improvements. With stainless steel prices on the rise and steel hinges having the tendency to rust, Bemis saw it as the right time to try molding plastic hinges for its toilet seats, says Steve Kolste, director of marketing and business development.

Bemis built on this idea, and soon it wasn’t only molding plastic hinges, but also plastic seats. During this time Bemis also received a request from a local company to make components, which got the company into contracting and later to the creation of the Contract Group.

Bemis strives to keep up with consumer demand and industry trends. The company says its competitive edge comes from its co-injection and co-extrusion molding technology, which enables Bemis to use recycled material in the production process. This type of manufacturing is what sets Bemis apart from many plastics extrusion and injection processors, according to the company.

Bemis’s growth throughout the years has resulted in two divisions. The bulk of the sales through its Proprietary Products division comes from the company’s toilet seats, and the Contract Group division is where it makes the parts that end up in other OEM products, Reinemann says.

The company’s footprint has also grown and today consists of six sites worldwide, including its more than 2 million-square-foot corporate headquarters in Sheboygan Falls. The facility is also home to one of Bemis’s injection plants and to the company’s extrusion plant.

All the machines in the injection facility are computer controlled and robotically attended and most are state-of-the-art co-injection molding capable.

The extrusion facility covers nearly 300,000 square feet, enclosing more than 30 single- and twin-screw extruders ranging from 2.5 inches to 3.5 inches in size. Single- and multi-layer capabilities are complemented by microcellular foaming, continuous glass pultrusion and a number of downstream part enhancement capabilities, according to Bemis.

Bemis also has an injection facility in Lenoir, N.C., that has grown to more than six times its original size since the company acquired it in 1998. Bemis also has plants in Italy, Mexico and England.

The company’s focus has always been on its manufacturing processes, which now include compression, extrusion and injection molding. Compression molding involves compressing plastic pellets into shapes, extrusion molding occurs when molten resin is pushed through a profile to form a shape, and injection molding involves depositing resin into a mold, taking that shape one piece at a time, says Dan Huhn, materials specialist, Bemis Contracting Group.

"Out of the three, injection molding is the most versatile and is the most common process for average resin consumers," Kolste says.

Bemis purchases a variety of both commodity and engineering grade resins. Engineered resins are typically more expensive and their physical properties are very specific compared to com-
modity-grade resins. In addition, engineering grade resins’ specifications are often narrower than those of commodity grade resins, Reinemann says.

The company sources its secondary resins and scrap plastics from a variety of suppliers, including specialty recyclers, molders and compounders. The companies Bemis purchases from vary depending largely on its volume and materials requirements at the time. Bemis incorporates some of its own scrap material into its manufacturing process, recovering and reusing initial start-up parts that might be thrown away by similar manufacturers. "The goal is to utilize everything we have here," Reinemann says.

Bemis’s co-injection and co-extrusion technology allows it to use recycled plastics in its production process, which ultimately reduces the company’s raw material costs. "It’s not something we’ve invented, but it’s something we’ve improved and become committed too," Kolste says.

According to Kolste, while co-injection first occurred in 1969, few companies are doing it. "Co-extrusion is fairly common, but co-injection is very unusual, and we believe we’re the largest co-injection company in North America," Kolste says

As to why other companies haven’t incorporated the use of secondary plastic in co-injection molding, Bemis can only speculate. "It’s harder to do from a molding perspective than injecting a part made of all the same materials," Reinemann says. "And, technologically speaking, there is some fear from the purchasing side as to whether it can be done and made into a nice looking, well-performing part."

Bemis offers proof that co-injection molding using recycled plastics can be done. The results not only reduce the volume of scrap plastics sent to landfill, but also save the company money in terms of raw material costs. "The more things we co-inject, the more cost- effective we can be," Kolste says.

The issue some companies have with using scrap or secondary resins is the additional work that comes with mimicking virgin material, including matching colors, cleaning the plastics and ensuring they are free of contaminants. For Bemis’s co-injection process, it does not matter if labels are present or if different colors are blended, because the process is going to hide the secondary plastics within the new plastics.

"We use it as filler [and for] performance improvement and cost reduction, and we can put between 10 to 15 percent of recycled material inside the new material," Kolste says. "And a lot of the costs to the recyclers may be eliminated because they may not have to do as much cleaning and separation."

Co-injection also gives Bemis the ability to combine materials. Say, for example, a customer wants a material that is chemically resistant and very stiff. Kolste says Bemis can buy very expensive material that’s highly chemical resistant and rigid or it can buy inexpensive chemically resistant material for the outside and put a rigid material on the inside.

When a customer wants a part, Bemis can look at the job in two different ways. "We can make the part out of brand new material or we make it out of partly new material," Kolste says. "It’s an advantage to our customers from a pricing and performance standpoint because a high-performance recycled material improves part function at a lower cost."

Bemis also uses recycled plastics in its co-extrusion process, where a thin layer of material is extruded around the recycled material. The company is able to get up to 80 percent recycled material into its co-extrusion products.

Bemis’s business is driven by a company philosophy that embraces continuous improvement. "What this means is something we think we solved today, we may be reinventing or improving tomorrow," Reinemann says. "And we have to do this in order to stay competitive."

Even though this philosophy pertains mostly to technology, Bemis also is always on the lookout for appropriate acquisitions, Kolste says. As part of the company’s growth strategy, Bemis is looking to increase its global presence in contract and proprietary products as well as to open a facility in the fast-growing Asian market, Kolste says.

Other ways Bemis plans to continue growing is by attracting more business from existing customers and by penetrating into new markets that it doesn’t currently supply.

Bemis has witnessed a lot during its first 100 years, from advancements in technology and machinery to fluctuations in resin prices to changing marketplace demands. The company has responded by making a number of adjustments to its manufacturing technologies, end markets and overall business philosophy throughout the years.

The author is assistant editor of Recycling Today and can be contacted at kmorris@gie.net.