TEXTILES.ORG
Manufacturers have set out to make a “better zipper” for nearly a century—even longer, if you consider early “slide fastener” and “clasp locker” concepts. When it comes to this small but vital mechanism, innovation is constant.
Today’s zipper manufacturers continue to transform the modest zipper with things such as impenetrable seals, recyclable materials and ease of customer repair.
Waterproof performance
Zippers that find homes in waterproof-rated products serve a crucial role in travel gear, wet suits, first-aid kits and more. TRU® Zip, a toothless, waterproof zipper by Nite Ize® of Boulder, Colo., quickly found a niche in countless industries and applications, including marine products, surf gear, camping gear and mobile phone accessories.
“Imagine putting a water-resistant zipper on a $400 shell where the rest of the fabric is waterproof,” says Rick Case, CEO and founder of Nite Ize. “Now somebody can use a fully waterproof zipper and even make waterproof pockets.
“We’ve built a zipper that you can open and close with one hand around radiuses and create a smooth, secure closure.”
TRU Zip’s standout feature is its IP67 dustproof and waterproof rating, making these zippers submersible in up to 1 meter (3.3 feet) of water for up to 30 minutes. A sleek, toothless look and easy sliding with minimal pull force complement this ability. It also boasts a closed zipper assembly and comes in sizes from 4 to 8 millimeters (more than 1/8 inch to almost 1/3) and custom lengths.
Nite Ize builds a collection of waterproof bags that demonstrate the benefits of TRU Zip. “With one product, we realized the zipper was capable of something else: It is leakproof in both directions. That allowed us to build all kinds of interesting things,” says Case, referencing the company’s RunOff® Waterproof Toiletry Bag. Other highlights in the collection are a Waterproof Packing Cube that can compress down or float when inflated and a Waterproof Phone Case with touch-screen-friendly functionality.
“We’re super passionate about the products we make; we’re users of these products and listen to our manufacturer, end users and customers. We’re reading the reviews and thinking about that experience,” he adds.
Tapeless and ‘chipped’ zippers
Sometimes the manufacturing process can be simplified to achieve something new. And sometimes technology ramps up to full effect.
Zipper manufacturer YKK, headquartered in Atlanta, Ga., did away with traditional zipper tape in its AiryString® product for a sleeker look and smoother pull.
“Typically with a zipper, you have the teeth and the tape,” says Brian La Plante, senior manager of sustainability at YKK. “[AiryString]’s zipper element is sewn directly onto the garment. It’s a streamlined look because all you see is the two textile fabrics coming together with just these elements showing.”
Another YKK project integrates electronics to help facilitate communication between brand and end user.
TouchLink zipper pulls containing a near-field communication chip embedded in a rubber pull allow users to tap it with their phone and connect to the internet, depending on what’s encoded on the chip. This opens the door to digital two-way communication where customers and brands can share information about care instructions, warranty registration or other sales and marketing.
“I could even tap it with my phone when I’m leaving my house for a run and start my playlist or send a notification to loved ones that I’ll be back at a certain time,” says La Plante. “It enables this new era of digital services that brands have not leaned into in the past.”
Materials matter
Materials are key to a zipper’s performance, longevity and sustainability. TRU Zip’s toothless zipper flange is made entirely from thermal plastic polyurethane (TPU) versus a traditional zipper where teeth are often plastic, which then is over-molded onto a second material with a polyurethane (PU) laminate.
“The idea was that we might be able to extrude TPU in a profile that would look like the rails of a zipper but without teeth,” says Case. “Instead, the rails would come together as a traditional slider.”
In addition, he says there is less of a chance of delamination because the whole surface is compatible with all TPU laminated fabrics. “It makes for a great radio-frequency welded surface, and manufacturers enjoy being able to weld it,” he says.
Materials are a big focus for YKK too. And more specifically, how those materials age and whether they can be easily recycled. Last year, the company launched the DynaPel® product. Without a PU coating, La Plante says the zipper is smoother, more flexible and breathable. It’s also easier to process at the end of life. “One of the big advantages is that it can be recycled within the developing textile circularity systems,” La Plante says. “The zipper can stay on the garment when [that garment is] processed because it does not contain PU contamination.”
DynaPel is forged from a molecular process applied to the tape through heat and pressure, which renders it highly water-repellent. “The heat and pressure help to bond the chemistry to the yarns and cure it to create a highly water-repellent surface that looks like
a standard textile tape,” says La Plante.
Repair within reach
Zipper makers join other industries as they move toward improved circularity and a product that is easier to repair. This benefits virtually everyone. “Our focus is really, ‘What can we do to keep garments in use longer?’” says La Plante.
For example, zippers on hand pockets on jackets and coats are notoriously challenging to repair. YKK’s product VISLON® with Revived Top Stop has a special tooth at the top of the zipper that allows users to replace the slider in case of a break and fix it without the challenge of removing the entire zipper. This keeps the whole garment in play much longer.
Likewise with TRU Zip. Case says the self-repair aspect of TRU Zip is a significant selling point. “We were able to work with the brands and ultimately change their warranty results based on performance.”
If TRU Zip separates, the self-healing technology allows the end user to pull the slider back toward the end stop and reseal. The fastener is airtight and capable of “impressive shear strength,” says Case.
“I could stand on this bag and induce a lot of internal pressure,” he describes, “and if I put both feet on it and really jump on it, I could blow apart the seal on the zip. What’s interesting about that is that we’re demonstrating that it’s not broken.”
An economic push-pull
In product development, price parity of sustainable versions can be an issue. “Customers are asking for more sustainable products. That’s a big request for them,” La Plante says. “But we find they don’t want to pay more than they’re paying now.”
Nevertheless, La Plante says YKK continues to work on sustainability efforts because the company feels it’s the right thing to do for society and the planet. On regulations that exist around eco-design, he says few are well defined, but his company has employed sustainability efforts since the 1930s. The company’s “Sustainability Vision 2050” addresses five key areas: greenhouse gas emissions, new material resources, chemical management, labor and water resources.
A big part of that vision includes developing various bio-based materials and replacement materials for what’s currently in use. Each “new” material is scrutinized for its strength, durability and importantly, its carbon footprint.
The recycled polyester (rPET) used in YKK tapes is mostly made from PET bottles. La Plante adds the company will likely transition away from rPET as the supply wanes.
“We’re starting to look for materials that have lower environmental impacts but still have a lot of the advantages of polyester in terms of strength and durability, colorfastness … and don’t necessarily contribute to microplastics and some of the other challenges you have with polyester,” he says.
La Plante is optimistic about the future of materials and their many possibilities.
“I think we’re in this golden era of new textile material development,” he says, pointing to innovations at the lab stage. “It’s just a matter of seeing if we can get them into the real world and get them to production scale. This part is extremely exciting.”
Sara Scullin is a freelance journalist based in Wisconsin.