Reflecting on Safety
Posted on Wednesday, May 23, 2018
Retro-reflective Coatings Change the Way We Look at Safety
Powder coating applications are frequently driven by powder’s well-recognized combination of beauty and brawn. For example, an architect might specify a durable powder to provide a cosmetic finish that must hold up against decades of outdoor exposure without fading, while an agricultural equipment manufacturer might select a powder coating that provides an attractive coating that can resist the caustic effects of harsh fertilizers. Occasionally, however, powder coatings might even save lives. Take the case of a bicycle rider cycling at night on a dark road, or a surgeon performing a delicate procedure that requires him to precisely navigate vital organs. Halo Coatings of Chesterland, Ohio, has harnessed the power of micro-sphere technology to provide powder coatings that make bicycles glow in the dark and let surgeons track their tools during medical procedures.
Referred to as “retro-reflective,” Halo’s powder coatings are remarkably efficient at reflecting even small amounts of light directly back to the light source rather than scattering it in many directions. “In ordinary daylight, the bike looks like any other powder coated bike,” explains Ryan Downey, one of Halo’s owners. “But at night, when a car’s headlights strike the retro-reflective coating, nearly all of the light is reflected back to the driver. This retro-reflectivity is so high in a single direction that the bicycle appears to glow.” Downey explains that this safety feature has attracted the attention of the bicycle industry, from high-end boutique builders to some of the highest volume bicycle manufacturers in the world, like Specialized Bicycle Components.
Working to perfect their retroreflective technology since 2010, Halo’s powder coating process is now nearly identical to that used for any conventional powder coating. That is, metal parts are pretreated, powder coated electrostatically, and then cured in an oven at 350-400 degrees Fahrenheit. “Our customers can usually use their existing powder coating equipment,” says Patrick Riley, Halo’s director of operations. Halo’s powder can be applied with all of the major brands of application equipment. “Although we are expanding our resources in our Cleveland-area facility, we did a lot of our technical development in Indiana with our friends at Gema, in their Indianapolis applications lab,” says Downey, who explains that the only part of the process that differs from most traditional powder coating is that the part surface needs to be hot. “To get the best reflectance, we have to find the right preheat temperature and get the right uniform film thickness. But other than that, the process is nearly identical to any traditional thermal cure powder line.”
The alternative to retro-reflective coatings has typically been costly prismatic tape. “For example, AT&T used tape on their repair workers’ helmets,” says Lisa LaBanc, Downey’s business partner. “But the tape gets dirty, the edges fray, and eventually it starts to peel off the helmet. So we developed a coated band that looks better and holds up to the elements.”
Another application where Halo’s retro-reflective technology is replacing the use of reflective tape is the development of medical markers that help surgeons navigate during medical procedures. The markers are illuminated by probes to create precise digital images, used to make incisions. “Medical markers help identify the location of tools very precisely,” explains Downey. Unlike the outdated tape technology, after surgery, hospitals can put the coated medical markers into an autoclave to sterilize them for further use. “The tape markers can’t be autoclaved, and are thrown away,” says Downey. That is a potential health risk, and it’s expensive.”
“It took a lot of chemistry and physics to develop a repeatable powder process,” recalls Riley, “but we came up with a very robust system that has reflectivity as good as reflective tape. And while tape is limited to simple, flat surfaces, our coatings can be used to make any part surface reflective.” Although the technology is robust, achieving the best reflective properties still requires attention to detail, and good process control. To ensure success, Halo targets larger manufacturers with good in-house technical capabilities. “In the past, we were inundated by requests from tinkerers with all sorts of novelty applications. To better serve the industrial market, we have focused on larger OEM applications that can leverage the time and effort that goes into developing these advanced applications,” says Downey. “For example, we have partnered with a large shopping cart manufacturer to produce carts that light up in a dark parking lot. A typical supermarket has lots of carts, and every customer cart that wasn’t put into a carousel becomes a potential accident.”
In addition to powder coatings, Halo also offers liquid retro-reflective coatings. “We can deliver reflectivity to a part regardless of whether it’s made of metal, plastic, rubber, or composite,” says Downey. For example, Halo has liquid coated the tires used on equipment for mining operations. “We have some customers that use powder, and some who use liquid, and I expect we will have customers who will use both. We are even working with low thermal cure and UV cure powder coatings, so we can powder coat plastic and composite substrates,” says Riley.
“We have a unique technology,” says Downey, “and we don’t want to be myopic. We tailor our approach to what the customer needs. We are not in the business of shipping powder but providing a reflective coating solution.” That relationship usually starts with a request to make a sample, explains Riley. “We usually do that for free, so the customer can see how a retroreflective coating will look on their product. If they like what they see, we come back with a business development agreement.” After product development and larger scale sampling, Halo usually works with their customers to bring the powder process in-house.
In late June 2018, Halo is scheduled to move into new and expanded facilities adjacent to its current Ohio facility. “Our new plant will provide more R&D resources and greater production coating capacity for customers who want us to help ramp up use of our technology by coating parts for them while they install their own powder line, “ says Downey.
- by Paul Mills, marketing and business development
consultant to industry chemistry and equipment suppliers