The core principle of electron beam technology is accelerated electrons break chemical bonds. What happens afterward (bonds remain broken, reform, and/or initiate a reaction) is chemistry. How this principle is used to create ebeam applications is up to your ingenuity!
Flexible Packaging
Interior/Exterior Architectural Products
Vacuum Skin Packaging
Sterilization and Disinfestation
Heat Shrinkable Films and Sleeves
Coil Coating
Tires
Pressure Sensitive Adhesives
Paperboard Packaging
…and much more!
Even within an individual application, ebeam can be used to achieve numerous effects.
How does ebeam work?
The future of ebeam is constantly evolving. At PCT, we help develop new applications — from modifying inorganic materials to curing 3D objects — using our pilot line, applications specialists and engineering team. The core principle is simple: accelerated electrons break chemical bonds. What happens afterward — crosslinking, chain scission or initiating reactions — is chemistry. How you use it to create new applications is limited only by your ingenuity.
An electron beam – or ebeam – uses accelerated electrons to affect material properties. These accelerated electrons are generated by electrically heating a filament, which releases electrons through a process called thermionic emission. The electrons are then accelerated by applying a voltage potential.
This process takes place in vacuum, but once accelerated, the electrons escape the vacuum by penetrating through a thin metal foil into atmospheric pressure, ready for production. As material passes in front of the window/foil, accelerated electrons penetrate into the material and work their science!
What can you do with ebeam?
Ebeam opens up a wide range of possibilities. By using accelerated electrons to break chemical bonds, ebeam initiates chemical reactions that depend on the type of material — usually a pre-polymer or polymer — and its chemistry.
Curing pre-polymers
With a pre-polymer starting material, such as monomer and/or oligomer, ebeam can cure (polymerize) the material into a polymer. Examples of curing include inks, coatings, overprint varnishes (OPVs), and laminating adhesives. Curing is sometimes referred to as drying because the coatings are applied wet and come out of the ebeam dry; however, this is a misnomer! Unlike thermal dryers that just evaporate water or solvent to dry a coating, ebeam solidifies the coating by bonding molecules together.
Modifying polymers
When the starting material is already a polymer, ebeam will break the polymer chains. These broken pieces can bond together in new ways to form a linked network, crosslinking, or the polymer chains can remain broken, a process called chain scission. Crosslinking and chain scission occur in concert; the dominating reaction is dependent on the polymer chemistry. For example, polyethylene is crosslinked by the beam, where as teflon (polytetrafluoroethene) degrades by chain scission. Chain scission is the process by which ebeam sterilizes materials; the DNA (a natural polymer!) of bacteria, pests, etc. is destroyed by the beam.
Grafting
The grafting process requires both polymer and pre-polymer as starting materials. In this process, ebeam bonds the pre-polymer onto the polymer. Grafting is used to modify the surface properties of a film or filter membrane. A common example is grafting a hydrophilic pre-polymer to a hydrophobic filter material to create a hydrophilic filter.
What are the benefits of ebeam?
Ebeam reactions are instantaneous. Delivering curing, crosslinking and sterilization on the spot. This speed translates into higher throughput with a small footprint. Depending on the application, a single beam can run up to 400 m/min, replacing multiple banks of UV lights or miles of ovens.
Energy efficiency
Ebeam technology is energy efficient. It takes less energy to run an ebeam than it does to run your typical industrial UV-curing set-up. Additionally, most ebeam processes take place at room temperature allowing heat-sensitive coatings and substrates to be used.
Color independence
Ebeam is color blind! Unlike UV curing, ebeam’s penetration ability is not dependent on optical clarity but instead material density. This means ebeam can cure richly pigmented inks, from white to black and the rainbow in between, without difficulty. Need to laminate to opaque materials together? Ebeam can do that, too.
No initiators needed
Accelerated electrons have enough energy to start reactions without chemical initiators. This makes ebeam ideal for food and pharmaceutical packaging, eliminating concerns about initiator migration. Ebeam curing is also solvent-free, producing low to no VOCs or odor, and crosslinking or sterilization can often be done chemical-free.
Improved material performance
Speaking of crosslinking, did you know that ebeam crosslinking can instantly improve a film’s heat resistance, solvent resistance, and provide uniform heat shrink? Crosslinking polyethylene (PE) is actually one of the oldest applications of low-energy ebeam technology. Furthermore, crosslinking generally adds strength to materials, allowing ebeam users the ability to downgauge their film without downgrading performance.
Got sustainability goals? Ebeam can help!
Sustainability is a growing priority in flexible packaging. From reducing waste to using recyclable materials and adopting greener processes ebeam supports all three pillars of sustainability:
Reduce
Ebeam enables film downgauging, eliminates the need for initiators or solvents, reduces energy use, and supports digital printing efficiency. Less material, less waste and smaller footprints all contribute to sustainability.
Reuse
Ebeam enhances durability and material strength, extending product lifetimes. Ebeam systems themselves are long-lasting; PCT’s pilot line has been operating for 35 years.
Recycle
Ebeam can aid recycling by breaking down materials through chain scission, making them easier to process. Ebeam-cured OPVs are compatible with compostable and recyclable packaging, including single-material pouches. Because ebeam coatings and inks are a small fraction of the material, they don’t hinder composting or recycling.
With ebeam, companies can meet and exceed sustainability goals while improving product performance, efficiency and safety.
New to ebeam? No problem.
Our applications development specialist is here to assist with questions, trial parameters, and/or connecting customers with ebeam-curable OPV and laminating adhesive suppliers. Whether you are adapting a current application or inventing something completely new, we are here to help!
Visit our Ebeam Pilot Line page or Contact Us to learn more.