by: Amy Bauer
A proprietary radio frequency (RF) welding technology from Genesis Plastics Welding is expanding the capabilities of traditional RF welding machines, allowing them to bond a wider array of materials, including many considered more “green,” or ecologically friendly.
The technology, called ecoGenesis™, has been in development for more than 20 years, according to Tom Ryder, Genesis president and chief executive officer. Today, the company applies ecoGenesis to products produced in its contract welding facility in Fortville, IN, and licenses the technology to other plastics manufacturing companies.
ecoGenesis is a system that “bolts on” to existing RF welding machinery and, using standard settings and no additives to the materials being welded, provides a strong bond between materials that previously weren’t candidates for RF welding, such as polyethylene, polypropylene, polyester, nylon and bioplastic. These phthalate-free materials are options to polyvinylchloride (PVC), which has become the subject of concern among consumer and health groups.
RF Then and Now
Traditional RF welding works by passing radio frequency waves through materials, exciting the molecules so that they heat up and meld together from the inside out; thus, creating a strong bond. Ryder described it as similar to a potato heating in a microwave, cooking from the inside out. While RF welding has been used extensively with PVC and polyurethane (PU), Ryder said one of the biggest downsides to RF welding has been its limitation primarily to such polar materials – those with molecules that because of their positive and negative poles attract or repel one another. Nonpolar materials are made up of molecules without positive and negative poles. Those materials like polyethylene, polypropylene, polyester, nylon and bioplastic – are candidates for ecoGenesis RF welding.
As described in a white paper paid for by Genesis Plastics Welding and The Dow Chemical Company, “Prior RF welding art allowed for only a few polymer films – like polyvinylchloride (PVC) and polyurethane (PU) – as candidates for a good RF weld.” Technical consultant OmniTech International was hired to evaluate ecoGenesis and “confirmed that films, copolymer films and fabrics with low dielectric factors (DLF) can efficiently and effectively be RF welded with ecoGenesis – without the aid of coatings, adhesives or other costly treatments.”
Other methods for bonding nonpolar materials include using heat sealing, impulse welding, adhesives or materials with polar additives, such as EVA, said Ryder, noting that each has its own drawbacks, whether limited dimensions to the weld or added materials costs. “There are other methods, they’re just not as efficient or cost-effective as ecoGenesis,” he said. By eliminating the need for expensive heat seal additives and allowing the substitution of lower-cost raw materials, ecoGenesis helps to keep costs down, the white paper notes.
Proving the Technology
While the company declines to disclose many specifics of the ecoGenesis technology, or how many companies currently are licensing it, Ryder says seeing has been believing for Genesis Plastics Welding customers. “The real gurus of radio frequency welding are very skeptical,” he said. “Because it’s proprietary technology and we’re not able to disclose or just hand over the technology to anybody without a license, to be honest with you, they don’t believe us.”
He says one of the best ways to convince those considering the technology has been by taking materials a company has tried unsuccessfully to RF weld, creating the weld using the ecoGenesis technology and sending the finished product back to them. If companies still express disbelief, Genesis offers a visit to the company’s facility for a nonconfidential demonstration. “We’ll have the technology hidden, and they come in, they see it’s a standard RF machine and none of the settings are changed,” he described. “And when they witness us welding it, they become believers.”
Ryder said the ecoGenesis technology can be added to any standard RF machine, large or small, as easily as a tool can be changed, allowing a shop to switch from welding PVC and polyurethane in the morning to welding nonpolar materials like polyethylene and polypropylene in the afternoon. Because it is an addition to existing machinery, Ryder said, companies are saved a large investment in capital expenses.
“The technology lasts for tens of thousands of cycles. It doesn’t leave any residues. It doesn’t require any additives in the materials that you’re welding. And it can be taken on and off the machines,” Ryder described.
Operating ecoGenesis doesn’t require an extensive amount of training, he said. Genesis coaches a company’s setup technicians. “If a company has technicians that are very familiar with using RF welding, they’ll actually find it very simple to use,” Ryder said. Those operating the machine in many cases may not even realize it’s there. “It changes nothing with the day-to-day pushing the buttons and making the product,” he said.
Because Genesis Plastics Welding operates its own contract welding facility, which includes the ecoGenesis process among 24 different RF systems, it has been able to develop products for some companies or do pilot runs, testing and analysis before licensing ecoGenesis to them.
Demand Grows for PVC-free
The push toward PVC and polyurethane alternatives is being driven in large part by public concerns about adverse health effects of phthalate plasticizers in some PVCs, which increase the material’s flexibility but also may leach out. Burning of PVC also releases harmful toxins, so disposal is a concern.
The Consumer Product Safety Improvement Act of 2008 (CPSIA) limits the amount of phthalates allowed in children’s products, and California’s Proposition 65 requires warnings on consumer products containing any of hundreds of chemicals that the state lists as known cancer- or birth-defect-causing agents. PVC-free and phthalate-free labels are becoming selling points for consumer products.
Ryder said large retailers are moving to reduce or eliminate PVC in their inventories. “Right now, companies like Staples, for example, are putting out press that says they want to be PVC-free in 2012 and 2013,” he said. “Wal-Mart’s giving better grades for PVC-free product. Target’s doing the same. Companies on the retail end are pushing that with their suppliers,” he said, noting that businesses are looking for solutions now rather than waiting to see if more regulations will follow.
In the case of loose leaf binders, buyers may increasingly be looking for phthalate-free binder covers and sleeves and sheet protectors, while still expecting a traditional binder look and feel. “And from a packaging standpoint, if you have a cloth product that’s not PVC and you add PVC packaging to it, you’re bringing your opportunity down with those retailers,” Ryder said.
In addition to the growing “green” buzz in the marketplace, Genesis Plastics Welding is incorporating a push strategy in rolling out ecoGenesis by working with materials suppliers looking for ways to use and market their materials to manufacturers. The Dow Chemical Company, which helped pay for the white paper on ecoGenesis, is one example. Another is a company called PolyOne GLS Thermoplastic Elastomers, with which Genesis recently partnered in welding phthalate-free medical devices and marketing the achievement.
“We’ve done a lot of networking with materials suppliers, because they’re the ones trying to push their materials to the manufacturers,” Ryder described, “and they’ve helped us in that sales process.”
Future of ecoGenesis
While the applications of ecoGenesis will continue to grow as new materials emerge, Ryder said he doesn’t see traditional RF-welded materials disappearing. “PVC is a good material. I don’t think it will totally go away,” he said. But he noted that the potential of some materials, such as bioplastics, has barely been tapped. “There’s new materials coming out every day,” he said. “And being able to switch from one to the other I think is a good opportunity because there may not always be a better advantage with polar materials every time.”
“ecoGenesis just provides people more opportunities and more options to choose from. It’s taking the RF technology and advancing its opportunities. It’s creating options. It’s not taking it away, it’s just making it better.”
To read the full white paper and learn more about ecoGenesis, visit http://genesisplasticswelding.com/ecogenesisplasticswelding/weldablepolymers.