There are several options for edgebanding adhesion, including EVA glue, PUR glue, pre-coated, glue-layer edgebanding and zero-joint edgebanding. While more than 80 percent of the market uses EVA glue, which is readily available and affordable, zero-joint edgebanding is becoming a notable alternative to glue adhesives.
What is zero-joint edgebanding?
Zero-joint edgebanding employs a pre-applied polymer functional layer that adheres to the board without glue. Activated by a laser, hot-air or NIR edgebander, the functional layer melts and fuses the edgeband to the board. Unlike glue adhesive methods, zero-joint only requires bringing two items together: The edgeband and the board. Aside from its simplicity, zero-joint is an advanced adhesion technology that brings several key benefits to millwork shop owners.
Board and the edgeband appear as one solid surface with no glue lines. The edgeband melts and infiltrates the board, preventing delamination due to heat or moisture.
3 reasons to adopt
Increases end-product quality: Say goodbye to glue lines! Zero-joint edgebanding provides a monolithic appearance that allows the board and the edgeband to appear as one solid surface. Glue lines are visible in many other adhesion methods, such as EVA glue, PUR glue and pre-coated glue-layer. Over time, glue joints collect dirt or yellow. As glue lines physically shrink and swell, a gap is created where dirt and bacteria grow. Combined with yellowing, which can be caused by UV rays or cleaning solutions, the visual appeal of edgeband applied with glue dramatically decreases over time. In contrast, the seamless joint and a high-performance seal of zero-joint edgebanding offers the flawless, clean appearance of total integration.
Even the best of glues don’t hold a candle to adhesive-free technology. Options for color-matching glue to substrate are limited. EVA or PUR glues are available in up to five colors, which at best can only complement the surface color. Zero-joint edgebanding steps into this void with hundreds of colors, each with a functional layer that perfectly matches the surface.
Eliminating glue eliminates the possibility of delamination. During application, the functional layer of zero-joint edgeband melts and infiltrates the board. The resulting high-quality seal prevents delamination and avoids the hassles of site visits to repair or re-glue edgebanding. Superior heat and moisture resistance makes this technology especially well-suited for spaces that are exposed to harsher conditions involving heat and steam, such as healthcare facilities, locker rooms, kitchens, bathrooms and labs.
Streamlines production: Compared to glue adhesives, zero-joint edgebanding allows for efficient production with less mess. Take a moment to imagine a production line without glue pots and all the downstream messes glue creates.
All shop workers know that EVA and PUR glue pots are a nightmare. Significant drawbacks of PUR glue, in particular, is the need for venting of harmful fumes and the increased effort needed to keep glue pots clean, involving consistent nightly purging to have a properly working glue pot the next morning.
Zero-joint edgebanding not only bypasses pesky glue pot maintenance, but also avoids spatter or glue messes inside edgebanders. Working with glue complicates the manufacturing process, with requirements for pre-heating and shutting down, and can result in accidental burns to operators, all of which is avoided with zero-joint edgebanding.
In addition to streamlining the manufacturing process, eliminating glue saves on labor costs. Production managers can cross glue pot maintenance off the daily task list and, most importantly, they no longer need a person at the end of each line wiping excess glue off boards. Instead, they can re-purpose this non-value-added labor to tasks that will move the business forward. Although zero-joint technology costs more upfront than glue-based edgeband adhesion, by the time you factor in glue costs, machine maintenance and labor costs, making the switch to this technology adds up to a smart move.
Fully achieving these results depends on the material properties of the functional layer. In the case of REHAU’s LaserEdge, for example, the polypropylene functional layer forms a permanent seamless bond that is heat and moisture resistant. While PUR glue provides strong adhesion and good moisture resistance, its limited color selection results in a minimal visible glue line and handling this glue increases complexity on the production line. An edgeband with a TPU (thermoplastic polyurethane) functional layer and pre-coated, glue-layer edgeband share similar drawbacks; they are softer materials with low pull strength and the potential for squeeze-out, requiring post-production board and machine cleaning from glue splatter. Long-term performance is also less impressive than with a polypropylene functional layer. Right off the line, TPU might look great, but the long-term performance is not as stable and visible glue lines can emerge.
Complies with modern specifications and expectations: Zero-joint edgebanding is offered in ABS and PP materials. As a result, it complies with non-PVC specification requirements, which are increasingly prevalent from healthcare to education to offices. With the spread of COVID-19, these requirements have become even more crucial as several specifications were written for emergency healthcare facilities that demanded the use of chloride-free materials. The absence of PVC does not diminish the durability of zero-joint edgebanding. On the contrary, its chloride-free technology is ideal for projects where a tighter seal and long-lasting quality are necessary.
A few years ago, millwork shops were hesitant to buy hot-air machines, because they were uncertain about the availability of edgeband with a suitable functional layer. While this edgebanding is still not as widely available as traditional PVC, growing adoption of hot-air machines is strengthening demand and greatly expanding zero-joint edgeband selection from stock programs. Custom stock programs are also available.
From homes to hotels, wherever appearance is at a premium, zero-joint edgebanding offers a seamless, integrated look with no glue lines. For high-maintenance buildings such as hospitals, schools and shops, forgoing the glue and choosing zero-joint edgebanding allows for a much more hygienic, easily cleanable product that meets non-PVC specifications. Regardless of the market segment, zero-joint edgebanding gives millwork shops a first-rate edge finish that elevates the appearance and durability of their end product and their company’s reputation.
Which edgebanders apply zero-joint edgebanding?
The functional layer on zero-joint edgebanding can be activated by a laser, hot-air or near-infrared (NIR) edgebander. No matter which machine is used, the end quality is the same.
The differences are in the manufacturing processes. Laser works faster and is typically ideal for larger volume shops. Companies of all sizes are beginning to invest in hot-air machines, which require a much lower capital investment than laser. For example, while a laser line typically starts at $750,000, hot-air can be as low as $200,000 to $250,000. With these lower machines costs, the market for zero-joint technology is expected to grow exponentially and ultimately this novel edging treatment will become the norm. Shops that do not make the switch may find it increasingly harder to compete.
The technical teams of machinery and edgeband manufacturers are well versed in this technology, so shops can count on having good support throughout this transition.
Source: Mark Kraus is director of engineering for the furniture solutions divisions of REHAU Americas. He has many years of experience in edgebanding technology, and spearheaded innovations such as developing the first laser edgeband production line in North America. Kraus can be reached at email@example.com. For information on REHAU, call 888-734-2810 or visit na.rehau.com/zerojoint. View the on-demand webinar offering technical information and case studies on zero-joint edgebanding.
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