Coating and laminating treatments enhance fabric performance in important – and multiple – ways.
Although researchers are making progress in fiber technology that imparts performance capabilities into the fabric, inherent qualities in fibers are not necessarily a replacement for coating treatments—or competition for coaters.
Alexium International is actively in the coating products business in about 80 percent of the textile markets that have to be FR, says Mark Valdario, technical sales, North America and Europe. For example, the company is working with the U.S. military on a 50-50 nylon/cotton blend material for soldiers’ garments that provides better protection than inherent fibers at a lower price.
“Inherent fibers have their own problems,” Valdario says. “Abrasion resistance, for example, is a problem with Nomex®. With the 50-50 nylon/cotton, the garment is still intact at 100 washes, and it has no change in its FR qualities.” The company is currently hoping—and preparing—for a wear trial for the U.S. military.
An additional natural market space, Valdario says, would be workwear, and although coatings are generally thought of as more expensive that may not be the case. And coated products allow customers to make a choice between fabrics with inherent properties and coated products. “You’re providing them flexibility, and that is money in and of itself,” he says.
Daren Silverstein, president of the CLI Group, Paterson, N.J., says the advent of more advanced fibers and yarns—and, therefore, textiles—has had an impact. “In a sense it’s competition,” he says. “If a fabric manufacturer can achieve certain characteristics in the fabric in general, then it doesn’t need post processing. Years ago, fabric manufacturing didn’t do that.”
In some areas, however, it’s created opportunities. “We make composite materials; we’re not just finishers,” Silverstein says. “Maybe those materials can be used in composites that weren’t necessarily suitable in the past.” He adds that there are also opportunities to compete with PVC products that weren’t available perhaps 10 years ago.
Imports have had an impact too, but “while that may close some doors, it opens doors, too. If you want to be the same and never change, changing textile technology and composites will probably put you out of business. But if you’re willing to be flexible and look at changes as opportunities, you may be changing the nature of what you’re doing and who you’re selling to,” he says. “You’re turning the gears in the back. We’re always looking for ways to turn our gears.”
Coating as an art
Based in Belgium, Pennel & Flipo, through its ORCA® range, designs, produces and distributes high-tech, protective, engineered fabrics for the marine, safety and industry sectors. The company was created in 1924 due to the (then) technical innovation of applying a layer of rubber onto a textile backing. “Innovation is rooted in the heart of our culture,” says Louis Courcoux, U.S. sales manager for Pennel USA Inc.,based in S.C. and a subsidiary of Pennel & Flipo.
Today, the company provides complex flexible textiles, coating on multi-dimensional woven fabrics and a variety of other products. It has been involved in coatings and fabric solutions used in hovercraft skirts, train and bus bellows, decontamination shelters, helicopter floats, oil booms, flexible tanks, lifting bags and inflatable boats.
With new laws that restrict certain chemicals and raw materials used in the industry, the company’s R&D department engineers have had to adapt and find alternative materials to comply with the restrictions. Still, “the coating of textiles is an art,” he says. “Even with the new technologies, you still need know-how from people.”
Courcoux specifically noted the company’s CSM (chlorosulfonated polyethylene)-coated fabrics that are used to make bellows and gangways for train and buses. [These fabrics] pass fire resistance standards accepted worldwide and are resistant to abrasion, extreme conditions, UV Light, and high or low temperatures.
The company works closely with its weaver as the initial textile is so important in terms of the finish product. “We visually check each meter to make sure it is up to our standard before we do the coating,” he says. Its coated fabrics made from a woven aramid are used in high-pressure lifting bags, for example.
The silicone coatings business has been steadily increasing. “Adoption of air bags drove a lot of that growth and that continues globally as other countries introduce mandatory air bags,” says Ronald Hanks, North American business director for Bluestar Silicones, York, S.C. In fact, this is the largest single textile market for Bluestar Hanks says.
“Silicones have better durability and resist UV and thermal degradation, which is why they’re used in automotive air bags,” Hanks says. “They can perform in 20 years just as they would the first year.”
“In America, there’s pretty good saturation, but even there, we’re seeing air bags being deployed in aircraft (first-class and the flight deck only, at this point). So there are things that will continue to drive air bag use.”
What else is new?
The burgeoning wearable technology market has taken an interest in silicone coatings. “We’re seeing the first signs that they will require some sort of protection of the electronics,” Hanks says. “That’s kind of exciting.” Companies are trying to develop it now, but that’s at “the very beginnings for sensors in clothing,” he says.
Although there are new technologies in development—new polymers, for example, might potentially have an impact—but market penetration would be challenging because of costs and reliability issues.
The challenge for silicon treatments are in oliophobic performance. “Resistance to oil and oil-based dirt is difficult for silicones,” he says. “Fluoros are better, but they’re being more regulated.” When silicones are wet, they get slippery, “but we’ve got ways to balance that,” Hanks says.
Janet Preus is senior editor of Advanced Textiles Source.