UV LED curing technology is no longer an emerging technology, but is being seen more and more applied to screen printing, flexographic, and digital printing. Sara Jennings from Phoseon describes the technology and the companies using it.
Today, UV LED lamps are improving the print quality, throughput speeds, and capabilities of devices used to print everything from bottles, labels, and backlit signs to Braille lettering.
Owners of printing equipment that use UV LED curing lamps are reaping measureable and marketable benefits including:
the ability to print on many thin or heat-sensitive substrates
substantial energy savings compared to arc-lamp curing
improved print quality, particularly with multi-colour imaging and fine text
higher levels of workplace safety
increased productivity with longer-lasting, lower-maintenance ink-curing systems
Developers of printing equipment are choosing UV LED curing technology because of the following advantages: the curing heads are small enough to be used in smaller, more compact machines. Without generating a lot of heat or consuming high levels of electrical power, UV LED curing units can produce deep, thorough curing on a huge range of substrates. UV LED lamps can provide controlled curing intensity on thin plastics, foils, and films that would soften, warp, or discolor under the heat produced by UV arc lamps.
Because a UV LED curing lamp is a solid-state electronic device, it can deliver more than 20,000 hours of operating life. Consequently, printing equipment owners don’t have to spend the time or money to change out the curing heads as often as arc lamps that have an average operating life of about 2,000 hours.
Here are examples of Screen printers using UV LED curing.
Serigraphie Richford in Quebec, Canada is using UV LED light sources to cure inks that are printed directly on cylindrical glass containers for some of the biggest brands in spirits, health and beauty products, wine, beer, and soft drinks.
OMSO, a manufacturer of container printing equipment, incorporated UV LED lamps in their Servobottle rotary screen-printing press. The press prints up to seven colours directly on plastic and glass containers, can handle wet-on-dry printing, and uses 50% less energy than previous models. OMSO is also using UV LED lamps in a new flexographic printing machine for the high-end, multi-color decoration of flexible and rigid tubes.
Empire Screen Printing in Onalaska, Wisconsin uses UV LED curing on new and retrofitted screen-printing devices that print rolls of labels.
ISIMAT, a German manufacturer of package-decorating equipment for health and beauty products, offers UV LED curing as an option for TH 8130 hybrid screen/flexo printing device for flexible tubes. The UV LED curing unit controls ghosting on full-colour images that are printed on thin adhesive-film sleeves that wrap around the tubes. Image quality really matters in the beauty-products business.
Digital Printing Here are some examples of digital printing-equipment manufacturers using UV LED curing units.
AB Graphic International, a supplier of specialized label converting and finishing machines, built UV LED lamps into their Omega digital Braille printing system for pharmaceutical labels, leaflets, and booklets. The Omega digital Braille printing system brings improvements in flexibility, throughput, and capabilities to any packaging market in which Braille marking is required.
Domino, a global manufacturer of digital printing and product identification solutions, is using UV LED lamps in their K600i digital black-plate system. It can print variable data on labels, tags, tickets, forms, security products, and direct mail at speeds of up to 245 feet/min. Because LEDs are instant on/off, the UV light shines only when ink curing occurs. This saves energy and production costs.
Heidelberg incorporated UV LED lamps in their Linoprint L narrow-web production inkjet printer. Using UV LED drying, the machine can print full-colour labels on everything from thicker shipping labels to very thin adhesive films and foils.
Stork SGP Prints uses UV LED curing technology on their DSI Label Press for wine, beverage, cosmetic, and pharmaceutical labels.
EFI is using UV LED curing units on their EFI Jetrion 4950LX narrow-web digital label printer and their EFI VUTEk GS3250LX wide-format inkjet printer. The Jetrion 4950LX LED digital label printer offers four-colour, 720 x 720 dpi resolution and speeds of up to 157 feet per minute. The GS3250LX is ideal for printing high-definition point-of-purchase graphics on rigid substrates or rolls of materials.
Mark Andy is using UV LED technology on an in-line flexographic press for printing labels, wraps, sleeves, tags, and tickets on heat-sensitive films and adhesive-backed labeling materials.
At Labelexpo Europe 2013, Siegwerk showcased its newly developed special UV inks for curing on a Gallus press with LED curing lamps. The six-colour combination press from Gallus comprised one screen printing unit and five flexographic printing units. The machine produced self-adhesive labels for health and beauty and food products, booklets for package inserts, and tickets.
The ripple effect of advances in UV curing Now the UV LED technology has been built into so many different printing devices, the benefits of innovation in UV curing and inks are spreading outward. Printing firms, packaging companies, and manufacturers are improving the productivity of their own operations while passing along some of the cost savings and quality benefits to their customers.
Because UV LED curing produces less heat than mercury arc lamps, Empire Screen Printing no longer must wait for printed materials to cool before they proceed to the next processing phase. They also don’t need a special ventilation system to remove ozone from the employee workspace. Empire Screen Printing has reported a 50% reduction in energy use and won awards and recognition for their use of “green” technology.
Designers of specialized printing equipment are choosing UV LED curing lamps because they deliver advanced capabilities, improvements in operating economics, and environmental advantages. Over the past few years, a growing number of ink companies have been working hand-in-hand with printing equipment developers to develop ink formulations that that are optimized for both UV LED curing and the specific application.
Users of UV LED curing and ink technology can expand the range of applications they can offer, run equipment at higher speeds, achieve new levels of print quality, use substantially less energy, reduce scrap, reduce VOC emissions in the workplace, and print on lower cost or more environmentally friendly materials.
joined Phoseon Technology in 2006 as an Applications Engineer. Today, her role as Customer Program Manager includes developing customer and partner relations, providing customers with technical support, and working with engineering to deliver whole product solutions. She received a Bachelor of Science degree in Mechanical Engineering from Portland State University in Oregon.