You see a chamber filled with flames when you walk into the room. Another is subjecting the contents to extreme environmental conditions. Snow. Rain. Wind. Heat. Cold. The subjects undergo tests, and some age faster than nature intends.
You haven't walked into Dr. Evil's workshop or entered a scene in a science fiction novel. Instead, you've arrived at Avery Dennison's testing lab (where no humans are harmed).
The Avery Dennison lab puts high-performance tapes to the test: measuring flame retardancy, tracking performance in extreme weather conditions, and determining how long they will last in different scenarios.
This testing is critical, as Avery Dennison performance tapes, a line of pressure-sensitive tape (PSA) constructions, improve safety, comfort, and functionality in trucks, vans, vehicles, and electric vehicles (EVs). Here's how.
What is Pressure-Sensitive Adhesive Tape?
Pressure-sensitive adhesive tape sticks to a surface using pressure rather than substances such as heat or water. If you've used duct tape, masking tape, or medical tape, you've used single-sided PSA tape.
PSA tape is typically double-sided in many automotive applications to stick two components together. It comprises four layers:
- Layer 1: Adhesive.
- Layer 2: Backing.
- Layer 3: Adhesive.
- Layer 4: Release liner.
The exposed adhesive side laminates (i.e., affixes) to a surface (the "substrate), which might be metal, rubber, or plastic. The release liner remains on the other side of the tape until it is ready to be used. Then, you peel off the liner to affix the tape to another surface.
How Are Pressure-Sensitive Adhesive Tapes Used in Work Trucks?
PSA tapes are incredibly versatile. They are used to improve truck functionality, driver comfort, and safety in work trucks.
Bonding: PSA tape keeps truck parts in place, like rubber gaskets that seal out water or parts mounted to the exterior, to improve aerodynamics or aesthetics.
Harsh noise reduction: PSA tapes have visco-elastic properties that can dampen vibrations, reducing noise in the cab and improving the noise vibration harshness. For example, some tapes use low-friction materials like felt or flock so that when affixed to parts, they don't produce aggravating noises, sometimes called buzz, squeak, rattle.
Road noise reduction: Performance tapes made with foam absorb road noise. "If you're using a work truck, that's your office," said Max VanRaaphorst, Business Development Manager, E-Mobility and Automotive for Avery Dennison. "You might be in it 8, 10, or 12 hours daily. So reducing noise is important and helps many folks do their work comfortably."
Safety sensors: Vehicle safety features rely on sensors mounted on various vehicle parts; PSA is often used to affix them.
Shock absorption: Exterior parts like side mirrors are built with layers of PSA to absorb extreme vibrations caused by speed, wind, and jarring road conditions like potholes. "The amount of tape used inside a mirror is tremendous. You never see it because it's built like a sandwich," VanRaaphorst said. "You have to make sure when you're designing it, you're selecting the right tape to help mitigate the vibrations, or the mirror will fall off after a couple of years."
Seat heaters: Seat heaters can be bonded in place with tape, which improves driver comfort in cold weather.
"The number of applications and usages is immense," VanRaaphorst said. "Sometimes we're astounded by the creativity of people who take our products and integrate new, different things that we wouldn't have thought about, and they make it work."
Performance Tapes for Electric Vehicles
One of Avery Dennison's latest innovations is PSA tapes explicitly designed for electric vehicles (EVs).
"We have found some unique needs specific to electric vehicles," VanRaaphorst said. "The electric vehicle market is the wild, wild West right now. There are a lot of different players, and they're all doing it differently and uniquely. So this has posed some unique challenges and common problems we've worked to solve."
A common electric vehicle need is reducing the risk of flammability in the battery pack. EV batteries hold a lot of energy; if a short happens, their temperature can spike to 1000 degrees Celsius or higher. "OEMs are concerned about one battery failing and igniting all other batteries inside the battery pack. If they use the wrong tape, one battery goes off, and the tape will act like a fuse that carries the fire to all the other areas of the battery," VanRaaphorst said.
For this reason, flame-retardant-rated tape is a must for electric vehicles. In response to the need, Avery Dennison created Flame Tough adhesive, which is fire-resistant and reduces the chances of flammability.
PSA Tape for Electrical Insulation
VanRaaphorst said OEMs also use PSA tapes for electrical insulation in battery packs.
"Electric vehicles have so much electricity running through a battery pack, and that battery pack is usually made out of metal, which is conductive. Think about the shock you get when you rub your socks on the ground in the winter, then touch something metallic. Imagine that times 10 million. It could kill you. The solution to not have that happen is the right tape," VanRaaphorst said. "Tapes used for electrical insulation (a dielectric barrier or dielectric protection) keep things from arcing and shocking and causing failures. So, many of the metallic components are being covered in tape now to prevent electricity from arcing from the connections in the batteries to other areas."
A challenge Avery Dennison engineers helped address for electric vehicles is that sometimes the metallic parts that need to be covered have sharp edges or burrs that will cause the tape to tear. If that happens, the exposed metal could cause arcing, so they developed a tape that conforms around bumps and edges while staying intact.
"That's been a newer discovery and a niche solution we're able to offer," VanRaaphorst said.
Yet another PSA tape addresses one of the significant failures automakers — and especially electric vehicle manufacturers — encounter vibration-induced fatigue.
"You might have a part that is working fine in the beginning, but as it vibrates over time, those vibrations weaken the connection, causing a crack or failure," VanRaaphorst said. "The nice thing about tapes is that they can help absorb those vibrations and dissipate them so you can drastically prolong the life of the components."
Another challenge unique to electric vehicles is that road noise is far more apparent without the typical engine noise running in the background. PSA tapes can be used in the cabin to absorb this noise. Sometimes these tapes are combined with acoustical foam and used in the tires to absorb road noise.
"With electric vehicles, there's no best practice book; experts are writing it now. So Avery Dennison is helping write a few chapters of it, which is exciting," VanRaaphorst said. "It's a fun time to be nimble, and I think we have some unique solutions in our toolbox. We are willing to be there as a partner, and when dealing with different engineering challenges, we want to support you."