EB Curing Flexible Packaging Breakthough
Evolving EB technology applied to flexo and offset CI presses are competing to be a major factor in the future of flexible packaging. Electron beam technology is widely used in a variety of industrial applications, including wide web offset printing/coating, food preservation, food packaging & medical products sterilization, polymerization, transformation and cross-linking of plastic films, cross-linking of wire/cable insulations, welding, and the evaporating of metals.
What is EB Curing?
EB curing is a process wherein electrons are generated in a closed environment so as to impact specially formulated inks and coatings causing cross-linking (polymerization).
Electrons are generated from an electrified tungsten filament. Emitted electrons are then accelerated by the application of an electrical field in a vacuum chamber, which is sealed by a titanium foil window that is electron permeable.
Printed/coated product is transported outside the titanium window for exposure to the curing beam of electrons. Curing takes place in an isolated oxygen-free (less than 200 ppm) nitrogen flushed chamber.
Dose and Energy Density Are the Two Key Variables Controlling EB Curing
The dose is the number of electrons that are streamed at the product to be cured. It is dependent on the filament temperature or the current intensity applied. The speed or degree of cross-linking/curing is determined by dose and the substrate feed rate thru the curing zone.
Energy density of the accelerated electrons determines the penetration into materials to be cured. It is dependent on the high voltage electrical field that is applied.