Enews July 2023

Henkel celebrates 100 years of Adhesive Technologies

July 13, 2023

One hundred years ago, Henkel began selling its first adhesive solutions to neighboring companies. From the development of laundry detergent packaging adhesives for its own use to today’s advanced solutions in more than 800 industry segments the company’s world-leading adhesives, sealants and functional coatings are integral parts of countless consumer and industrial goods. Henkel Adhesive Technologies shares the visions of its customers and enables the development of groundbreaking innovations in areas such as sustainability, mobility and digitalization.

“With our pioneering spirit and innovative strength, over the last 100 years, we have become the world’s largest manufacturer for adhesives, sealants, and functional coatings, creating value for more than 100,000 industrial customers, as well as millions of consumers. Our next step to create value across industries around the world is to develop the sustainable solutions necessary that enable circularity and CO2 reduction,” explained Mark Dorn, Executive Vice President Henkel Adhesive Technologies. “Then as now, we collaborate with our customers to turn challenges into opportunities and to innovate products and solutions.”

The success story of Henkel Adhesive Technologies began 100 years ago, because the company made a virtue out of necessity. After the end of the First World War, the occupation of the Rhine and Ruhr threatened to cause a shortage of adhesives at the company’s home base in Düsseldorf, which were needed to seal the own product packaging for detergents. In 1922, Henkel therefore started to develop and produce paper, cardboard and packaging adhesives for its own use. With the construction and start-up of its own adhesives factory, the company also began selling adhesive products to neighboring companies on June 26, 1923. The first products included the painter’s glue Mala and the wallpaper paste Tapa, both based on potato flour.

A century full of highlights
Adhesive Technologies has globally pioneered through patented inventions, innovation power and strategic acquisitions. Inventions for example include the first Pritt glue stick in 1969, which took inspiration from the twist mechanism of lipstick and revolutionized papercrafts for more than 50 years. In 2001, Pritt was given a “Space-Proof” seal of quality and was sent to the International Space Station.

In the industrial sector, adhesive solutions from Henkel have transformed production processes and product designs in automotive, electronics, packaging and many more. The technologies provide tailored functionalities that include strong bond, sealing, coating, conductivity of heat and electricity, recyclability and many more. With the acquisition of the Loctite Corporation in 1997 Adhesive Technologies successfully integrated capabilities to move the business to a new level. Today, Loctite is the world’s largest adhesives brand.

Henkel has demonstrated the diverse performance capabilities of its solutions in many ways over the past 100 years. In 1987, for example, Ceresit products were used in the renovation of the Great Wall of China. And in 2015, Henkel developed a customized adhesive to professionally reattach the broken-off beard of Tutankhamun’s famous death mask.

“We are very proud of our success story of 100 years at Henkel Adhesive Technologies. A look at the last 100 years impressively shows the continuous development of our technological know-how and market expertise. With this strong history of innovation and remarkable achievements behind us, we look forward to a bright future where Adhesive Technologies continues to make history and create the solutions of tomorrow,” concluded Mark Dorn.

Globally leading with high-impact and sustainable solutions
The central focus of Adhesive Technologies’ innovation activities today is on developing sustainable solutions for its customers. The business unit is consistently working on products that enable resource efficiency in production and during use throughout the entire life cycle and that are based on renewable or recycled raw materials. In addition, Henkel offers a growing portfolio for the recyclability of, for example, packaging or consumer goods and the repairability of everyday products.

To take its innovation capabilities to the next level, Adhesive Technologies has opened its Inspiration Center Düsseldorf at its home site in 2022. In this modern innovation center with more than 30 laboratories, over 650 Henkel experts work on highly effective and sustainable solutions in adhesives, sealants and functional coatings. At the same time, the state-of-the-art building serves as a global customer center where Adhesive Technologies presents its entire technology portfolio and strengthens collaboration with its customers from over 800 industry segments. In 2023, the business unit will gradually open another global innovation center in Shanghai. For more information, visit www.henkel.com.

Baumer hhs Establishes Offices in Mexico

July 13, 2023

The Baumer Group, a manufacturer of sensors, angle sensors, measurement instruments and automated imaging components, with headquarters in Frauenfeld, Switzerland, established company offices in Mexico on May 1, 2023. Baumer hhs, a wholly owned subsidiary of the Baumer Group and an internationally operating manufacturer of industrial gluing systems in conjunction with quality assurance equipment, also will now be represented in the Latin American country by a team of several employees.

“Our company maintains very close connections with customers, as reflected in our global presence, and they appreciate that. We are very pleased that our parent company has established a subsidiary in this large and populous Latin American country. It has put in place the necessary infrastructure for Baumer hhs to also support customers locally, with its own sales and service experts,” said Igor Pinto, general manager.

The company is currently putting together its team of specialist in Mexico. “We are looking for several qualified employees for sales and service in Mexico City, Monterrey and Santiago de Querétaro. Our objective is to show existing and new customers the numerous possibilities that our equipment offers to optimize their processes,” Pinto said. “We want to support these customers by giving them access to local company representatives who understand the complexities of their needs and speak their language.” New team members will receive training at the company’s expanded hhs solution center in Krefeld, Germany. Learn more at www.baumerhhs.com.

BOBST North America to Open Competence Center

July 13, 2023

Bobst North America has announced its plan to open a brand-new Competence Center in Atlanta, Georgia, featuring its latest flexible packaging and label printing technology. The center will provide a unique opportunity for converters and brand owners to see BOBST’s pioneering technologies in wide-web and narrow-web flexo, digital, flexo and hybrid printing, and lamination.

“This new Competence Center will be around five times the size of our previous demonstration center in Alpharetta, Georgia, and by adding flexible packaging solutions to our label portfolio, we are putting the full range of BOBST’s offer firmly on the map here in the US,” said Emilio Corti, region business director, Americas at BOBST. “The center will allow visitors to see our latest technologies up close and even try out their jobs on our machines. It will be a new hub of innovation and collaboration in the US market.”

The new Competence Center demonstrates BOBST’s commitment to supporting its clients in the US, offering the ability to view, understand and test printing and converting solutions directly. Visits with experts – physical or virtual – are entirely tailored to clients’ requirements, encompassing machines, workflow solutions, substrates and services. The facilities provide the ideal environment for clients to conduct trial runs and laboratory analyses, without disrupting their planned production schedules in their factories. The new Competence Center will open in early 2024. Learn more at www.bobst.com.

Gallus One, Mastermatrix Debut at HEIDELBERG’s Summer Innovation Showcase

July 13, 2023

With a continued focus on the optimization of people, processes and technology, HEIDELBERG USA welcomed over 150 customers from throughout North America to the Print Media Performance & Training Center (PMPTC) in Kennesaw, Georgia, for its Summer Innovation Showcase held in June. The event featured a variety of live demonstrations and seminars highlighting HEIDELBERG’s full product and service offerings for the commercial, packaging and label segments and included the North American premiere of the Mastermatrix 106 CSB diecutter and world premiere of the Gallus One digital label press.

Attendees explored HEIDELBERG USA’s PMPTC featuring the Speedmaster XL 106-8P+L, Speedmaster CX 104-6+L, Stahlfolder TH 82 with new robotic P-Stacker, Stahlfolder KH 82, POLAR 137 System 200 and POLAR 78 cutter, Easymatrix 106, Diana Easy 115, Versafire EP & EV and Prinect Production & Business Manager.

“We called this event ‘Innovation Showcase’ to demonstrate the efforts we’ve taken to stay at the leading edge of product development to support our customers’ pursuit of efficiency,” said Felix Mueller, president of HEIDELBERG North America, “but we are more than machines. We also wanted to highlight innovations – like our approach to industry training – that aren’t purely technologically driven.” In addition to equipment and software demonstrations, customers had the opportunity to learn about HEIDELBERG’s Operator & Maintenance Training courses and toured the impressive renovations the company has made to its Training Center since the facility launched over a year ago.

Making its North American debut at the Innovation Showcase, the Mastermatrix 106 CSB, with speeds up to 9,000 sheets per hour, is HEIDELBERG’s newest and fastest diecutter from partner Masterwork. In addition to faster running speeds, the machine features a variety of innovations all designed to maximize efficiency and user-friendliness and minimize makeready times. Machine highlights include a cam-driven diecutting station for optimized sheet transfer, a motorized feeder head with built-in rear joggers, and the new EasyRake system that makes positioning and fastening individual delivery non-stop swords quick and easy.

Center stage at the Innovation Showcase was HEIDELBERG’s highly anticipated Gallus One digital press. The new roll-to-roll press, which utilizes Fujifilm Samba printheads, prints CMYK+W up to 13 3/8″ (340mm) wide at 98 ft/min (30 m/min) or 230 ft/min (70 m/min). With 1200 x 1200 dpi resolution, the Gallus One achieves offset-like quality and 85% white opacity at top running speed. Learn more at www.heidelberg.com.

Grafotronic Announces Appointments, Two New Subsidiaries

July 13, 2023

Press release submitted on behalf of Grafotronic

Grafotronic Appoints Seasoned CEO, Peter Cederholm, to Spearhead Label Finishing Market Expansion and announces at the same time two new subsidiaries in the Benelux and the UK.

Grafotronic, a leading provider of innovative solutions for the label finishing industry, is proud to announce the appointment of Peter Cederholm as the new Chief Executive Officer. With a wealth of experience and a proven track record in the international industrial machinery sector, Cederholm brings valuable expertise and leadership to drive the company’s growth strategy in the label finishing market.

Cederholm, a Swedish national, has a diverse background that includes living and working in different regions around the world. Having spent two years in the United States and five years in Singapore, he has gained a deep understanding of international markets and developed a global perspective on business operations.

Educated with an M.Sc. in Industrial Management & Mechatronics, Cederholm possesses a solid foundation in both technical and managerial aspects of the industry. He has held various senior positions throughout his career, including Vice President Reachstackers and Senior Vice President of Sales & Markets at Kalmar, as well as President of Bromma at Cargotec. Cederholm has been an international executive since 2009.

In addition to the appointment of Peter Cederholm as CEO, Grafotronic is also excited to announce the establishment of two daughter companies to further strengthen its market presence. The newly formed Benelux subsidiary will be managed by Patrick Brouns, bringing extensive knowledge of the industry and a strong network in the region. Meanwhile, the UK subsidiary will be headed by industry veteran Paul Hughes, who brings a wealth of experience and a deep understanding of the local market dynamics.

The expansion into new territories with dedicated subsidiaries under the experienced leadership of Patrick Brouns and Paul Hughes highlights Grafotronic’s commitment to providing localized support and tailored solutions to customers across different regions.

“With the appointment of Peter Cederholm as our CEO, we are confident that Grafotronic will continue to innovate and excel in the label finishing market,” said Ben Mitchell, Chairman of the board at Grafotronic. “His international experience, extensive leadership background, and strategic vision make him the ideal candidate to lead our company into the future. We are also thrilled to have Patrick Brouns and Paul Hughes join us in driving our expansion into Benelux and the UK, respectively. Together, we will work towards achieving new heights of success and cementing Grafotronic’s position as a global leader in the industry.”

Sun Chemical Introduces Digital Pigment Catalog in Pigment Finder

July 11, 2023

Press release submitted on behalf of Sun Chemical

Sun Chemical has introduced a digital pigment catalog for registered users of its Pigment Finder online platform.

Pigment Finder is a self-service platform that allows users to search and compare products and access technical product information, data sheets and pigment certificates. Using a variety of filters such as industry, color space, brand or chemistry, Pigment Finder users can now create customized product catalogs from the complete Color Materials portfolio.

These customized catalogs provide an overview of the most relevant technical data points for selected portfolios and can be exported or saved in users’ accounts. Thanks to automatic updates, the digital catalogs reduce the need for distribution of printed product brochures which may become outdated within a few months.

In celebration of the launch of digital catalogs and to promote user registration, Sun Chemical planted 5,000 trees in May for a total of 4,850 registered user accounts. The trees were planted through One Tree Planted, a non-profit organization focused on reforestation with the vision to make it simple for anyone to help the environment by planting trees. To reflect the global participants of the initiative, Sun Chemical divided the planting of the 5,000 trees into three different projects in the Americas, Asia Pacific and the EMEA region.

“Digital catalogs enable the real-time creation of customized pigment selections from our Pigment Finder database. Together with the access to technical information, color visualization and targeted customer support, digital catalogs enhance the efficiency of users’ experiences,” said Anna Herbst, Head of Strategy and Business Excellence, Color Materials, Sun Chemical. “We wanted to say thank you to our Sun Chemical Pigment Finder registered users by planting trees in their names. In addition to showing gratitude for our users, planting trees was also a symbolic gesture highlighting the transformation from printed –– and prone to being quickly outdated –– brochures to using digital product information, which is regularly updated and much more environmentally friendly.”

For more information about Sun Chemical’s Pigment Finder and how to use the digital catalogs, visit https://colormaterials.sunchemical.com/by-product/pigment-finder-videos/.

AWT Labels & Packaging Acquires ASL Print FX

July 11, 2023

Minneapolis, Minnesota-based AWT Labels & Packaging, Inc., a provider of custom labels, flexible packaging and precision converting solutions for healthcare, consumer brands and technology companies, announced the acquisition of ASL Print FX, headquartered in Vaughan, Ontario, Canada, and with locations in Napa, California, and Winston-Salem, North Carolina.

Operating for over 50 years, ASL provides print solutions to beverage, consumer packaged goods, envelope and promotional markets across North America. The acquisition complements AWT’s key end markets with an expanded geographic footprint, printing and embellishment capabilities and an enhanced portfolio of print solutions.

“We are grateful and thrilled with the opportunity to have the ASL Print FX team become a part of AWT Labels & Packaging,” said Bruce Hanson, CEO of AWT. “The cultures at both AWT and ASL emphasize trust, expertise, collaboration and customer partnership. We are excited for all our employees. The geographic fit between our two organizations, along with the strong leadership team in place should allow us to unlock customer value immediately.” Learn more at www.awtlabelpack.com.

Eagle Systems In-Line Foil Enhances Print for Brodnax 21c

July 10, 2023

Press release submitted by Eagle Systems, Inc.

Eagle Systems, Inc., a U.S. based developer and manufacturer of foil enhancement equipment, today announced that Brodnax 21c has installed an Eco-Eagle Cold Foil Module on their most recently acquired 8-color Heidelberg press. The installation was completed in November with one client in mind and is already creating a demand among the area’s prominent retail and brand packaging clients.

“A very smooth installation enabled us to begin generating real product to satisfy our partnering relationship with a customer and now we’re expanding our customer base,” notes Brodnax 21c Principal Jim Singer, “the Eagle System was installed and running live jobs for a sports trading card client who requested foil. Plus, we’re getting word of mouth inquiries from the most demanding national brands.”

The creative community knows the quality produced by Brodnax 21c Printing. Since the late 1950s, founder John Brodnax showed Dallas creatives lithographic magic. Today, Brodnax 21c employees are still old-school craft printers using the latest tools to provide traditional quality with modern efficiency on a four-building campus in the Dallas metropolitan area.

“We invested in digital printers in the early 2000’s,” adds Singer. “In 2013 we added our first wide format flatbed. We’re standardized on the forty-inch Heidelberg presses so that work can flow between presses including jobs destined for the in-line cold foil enhancement. We’ve achieved remarkable efficiency due to the Eagle’s tight resolution and speed matching the press. With the Eagle’s precision we can even rewind a foil perfectly for another pass with the same roll of foil.”

“We’re using cold foil to metalize packaging runs at a total material cost less than half what we would pay for metalized carton stock and running at the full rate the presses are capable of,” he continued.

“Seeing our company invest in this technology also builds morale in our staff. Our plant manager saw the Eagle System in action at a trade show. Eagle President Mike King fulfilled on all promises from delivery date to training and even after operational sign-off, he sent us his best trainer to train additional staff. If anything, he under-promised how it performs by 75% and over delivered on service. We couldn’t be happier with this vendor relationship. Mike King was not only critical to the success of the start-up but has continued to support us. The Eagle sits on a Heidelberg XL 8 color with heavy LED and Mercury curing capacity. The training and support were exceptional, and we have cold foil imaged and printed inline close to 10 million 28×40 in the last 6 months. We are also interested in the cast and cure Eagle System and will likely make that investment in 2024,” said Jim Singer.

“We’ve experienced an increasingly rapid global adoption of cold foil in recent years,” said Mike King, President and CEO, Eagle Systems. “Cold Foil enables service providers to offer their clients an innovative option that transcends the demands of their most high-end customers. Simply stated, it gives them the ability to say ‘yes’ to more projects, with less time and money required to make it happen.”

Tecnau acquires all operating activities of Sitma

July 10, 2023

Press release submitted by Tecnau

Tecnau, a global market leader in paper handling, monitoring, processing and finishing solutions for the digital print industry, announced today the acquisition of all operating activities of Sitma Machinery S.P.A.

Sitma was founded in 1965 and is today a global leading company in the fields of:

Direct mail and transpromo packaging systems: document inserting systems, paper wrapping and intelligent solutions for personalized mailings and advertisements.
Postpress: collating, inserting, addressing, paper or poly wrapping systems targeted at magazines, books and newspapers manufacturers.
General packaging: innovative and versatile film packaging systems with modular design for a wide range of formats and types of packaging for consumer, food and industrial goods.
E-logistics: technologies for sustainable packaging including (i) dynamic and pack to size paper-based systems for books and e-commerce markets and (ii) parcel sorting solutions for books, postal services and other intralogistics markets.

The move allows Tecnau to strengthen its position in the graphics industry with the addition of a well-established brand and product portfolio and to boost its diversification in the e-logistics segment (packaging for ecommerce and intralogistics), started recently with the opening of its new division, Tecnau Automation & Packaging.

With head offices in Spilamberto (in the North of Italy, outside Modena) Sitma has sales and service branches in France, Japan and the United States, which adds to the well-established Tecnau direct presence in the United States, Germany, Belgium, Singapore and Sweden to strengthen Tecnau’s local presence in key markets and geographies with direct sales and service support. In addition both Tecnau and Sitma possess a professional and long term distribution and agency network in over 50 countries worldwide.

“We are very excited to welcome all Sitma employees, customers and partners to the bigger Tecnau family” stated Stefano De Marco, chief executive officer at Tecnau. “Sitma has a long history in the graphics business with a very consolidated and high-performance product mix. Over the last few years Sitma was able to diversify and apply its technical expertise to the fast-growing e-commerce business, developing sustainable, pack-to-size technological solutions as well as energy saving and low-running-cost parcel sortation systems. Tecnau endorses this strategy and will provide all the necessary support to retain and expand further the wide customer base in traditional segments and to broaden the portfolio and customer base in new growing areas. We’re of course very interested in possible synergies between these recent Sitma innovations and Tecnau’s new Automation & Packaging division”.

State of UV LED Curing Applications

June 5, 2023

By Jennifer Heathcote, GEW, Inc.

This article originally was published in UV+EB Technology (www.uvebtechnology.com) and has been updated.

The list of viable UV LED applications continues to grow – as does the number of system suppliers, formulators and original equipment manufacturer (OEM) machine builders supporting those applications. This ongoing increase in activity bodes well for the present and future of UV LED technology. As a result, those who aren’t already investigating its suitability for their own curing needs may find it is time to start. For newcomers, as well as those who have been following or even using the technology for years, this article is meant to provide insight into the growing UV LED market space and to offer general guidance regarding how to match a UV LED curing system to the needs of a given application.

UV output

Inks, coatings, adhesives and extrusions are formulated to react to a given UV LED output under a specific set of process conditions. For each application and formulation, there is a UV process window within which acceptable cure can be achieved. This window is not narrow, but there is an optimal set of wavelengths as well as a minimum and maximum irradiance and total energy density combination that results in proper cure. Consistently operating within this window better ensures maximum material handling speeds, a non-tacky surface, depth of cure, post-cure migration within established limits, optimized production yields, product quality over time and optimal product life within the intended use among other desired performance criteria.

UV LED technology performs well when UV output is correctly matched to the needs of the application and paired with a suitably formulated ink, coating, adhesive or extrusion. Unfortunately, there is no universal UV LED system or process window that works equally well for all applications across all markets and machine types. The UV LED solution and its output must be chosen for the formulation, coat weight, plant or shop environment and the configuration and speed of the material-handling system.

A benefit of UV LED technology is that the discrete nature of LEDs allows for a much wider range of curing system designs that can better fit the needs of each unique application. This allows both lamp head form factor and UV output to be tailored to the respective markets and applications, resulting in much more efficient and economical UV LED curing solutions when compared to conventional curing technology. As a consequence, this also means there is a wide disparity in cure performance among commercially available vendor offerings since the inherent designs can be very, very different, and those differences are not always obvious to OEMs and end users.

Application evolution

UV digital inkjet pinning and full-cure in both scanning carriage and narrow single-pass printers, screen printing and spot-cure bonding adhesives used in product assembly were the first applications to adopt UV LED curing in the mid to late 2000s. What these early applications had in common was slower line speeds and longer part processing times. While the irradiance (watts/cm²) emitted from a single UV LED system during those early years was low, it was possible to deliver just enough irradiance by mounting the lamp head within 10 to 15 mm (0.4 – 0.6 inches) of the cure surface. For energy density, the solution was longer periods of exposure in static installations and utilizing multiple passes in dynamic ones.

Early UV LED applications required lamp lengths that were typically less than 450 mm (17.7 inches). When combined with the fact that many applications required just one or two lamps to achieve cure at speed, the total commercial investment was significantly less than systems needed for wider, high-speed commercial presses that needed multiple lamps and wider lamps. All these factors were crucial, as early UV LED systems were not very powerful and often were more expensive than conventional options.

Over the past 20 years, UV LED technology has improved dramatically in terms of performance, reliability, life, output and length. In fact, single span lamp heads are now available in lengths up to 2 meters (78 inches) and lamp life often exceeds 40,000 hours. In addition, many formulations are now specifically optimized for UV LED output. The market is also better at matching the UV LED system to the needs of the process window, and the price points of both equipment and formulations have improved due to economies of scale and more competition throughout the supply chain. This has allowed UV LED curing technology to move beyond UV digital inkjet, spot cure, and screen into more demanding, higher speed and wider commercial applications – both analog and digital. This includes sheetfed and web offset, dry offset, flexo, wood coating and finishing, and fiber optic coating.

Table 1. Areas of use for UV LED technology

Table 1 represents areas where UV LED technology is increasingly being used today – albeit at varying levels of market penetration and not necessarily for all applications within each market segment – but that will continue to improve with time. Different UV LED lamp designs, as well as application-specific formulations, are needed to make the many diverse printing, coating and bonding processes feasible. As a result, it is important that, for each application, there be a strong working relationship among all parties – UV LED curing system supplier, formulator, OEM machine builder, integrator and end user. In all cases, a viable UV LED solution can be achieved with some trial and error and process optimization provided a viable formulation exists. It all comes down to identifying the process variables and matching the UV LED system to the application, formulation and material-handling equipment.

Matching UV LED systems to the application, formulation and material-handling equipment

There is an ever-increasing abundance of UV LED curing systems and vendors from which to choose. All claim very similar product features and operational benefits, with the most obvious differentiators being peak irradiance, cooling method, lamp form factor and system integration. Unfortunately, knowledge of these alone is insufficient for matching UV LED curing systems to a given application. Technical spec sheets rarely provide explanations as to why product(s) are best suited for a given application and seldom reference nominal electrical input power and energy density at a given web, sheet or part speed. When matching a UV LED curing system, the following general guidelines should be considered.

Final cure properties
The desired mechanical, chemical, functional and aesthetic properties of the final cure as well as the intended product use should be specified and are instrumental in driving the formulation chemistry and, ultimately, whether a UV LED cured solution is possible today. For example, inks, varnishes and free radical syrup adhesives generally cure well with LED and meet most graphic print requirements. Silicone release, UV hotmelt, and industrial hard coats, however, are still very much in development and years away from wide-scale commercial availability.

Wavelength
Commercial curing wavelengths currently include 365, 385, 395 and 405 nm. For most ink applications, 395 nm is the preferred wavelength, with 365 and 385 nm wavelengths used to a lesser degree. Structural bonding adhesives typically work best with 365 or 405 nm, depending on the formulation, but also cure similarly with 385 or 395 nm. Overprint varnishes tend to match the ink wavelength of 395 nm, and when it comes to industrial coatings – both functional and hard – there is no consensus, as development is still ongoing.

Irradiance window
The formulation chemistry must be cured within a minimum and maximum peak irradiance (watts/cm²). Operating below a minimum irradiance will result in insufficient cure. Increasing irradiance beyond the maximum does not necessarily produce better results than curing within the established irradiance window, provided the lamp emits enough energy density. Unfortunately, there is no universal irradiance that meets the needs of all formulations. Each market application is different, with the optimal emitted irradiance at the window spanning anywhere from a few hundred mW/cm² up to and even beyond 30 W/cm². More important than the emitted irradiance, however, is the actual irradiance that is delivered to the substrate cure surface, as irradiance decreases with the square of distance traveled. Since a watt is a joule/second, irradiance can be rewritten as joules/second/cm² and is the rate at which ultraviolet energy is emitted from the UV LED lamp head. It is important to note that once the irradiance saturates the chemistry’s ability to absorb ultraviolet wavelengths, excess irradiance converts to thermal energy at the cure surface.

Energy density window
The formulation and manufacturing line speed determine the energy density (joules/cm²) needed to fully react the chemistry. A greater energy density results in a better overall cure, allows for a faster line speed and sometimes enables a lower peak irradiance. Not all UV LED systems emitting the same peak irradiance deliver the same energy density. Energy density can be increased by using a lamp which, by design, emits greater energy density, using multiple lamps in combination, slowing the line speed or increasing exposure time.

Working distance
This is defined as the offset between the UV LED emitting window and the cure surface. It must be specified for the application and machine set-up, as irradiance decreases quickly with distance. To accommodate greater working distances, consider more powerful lamps (either greater irradiance, greater energy density or both) or an LED solution that incorporates optics or reflectors to contain or collimate the UV wavelengths over a specified distance.

Cooling mechanism
The plant environment, preference of the OEM or end user and UV LED system design determine whether the cooling mechanism is forced air or circulated water. Not all UV LED products are available in air-cooled variations, and higher-powered systems typically are water cooled. Air-cooling can be either positive where air is pushed into the lamp head and exhausted to the press environment or negative where air is pulled through the lamp head from the press environment and ducted away. Since UV LED systems do not emit ozone, it is not necessary to exhaust the cooling air outside the facility.

Mounting space
The mounting location and machine set-up determine the allowable space for the UV LED head. Water-cooled systems are generally more compact than air-cooled systems. Air-cooled systems also require a minimum clearance around air inlets and outlets to ensure adequate circulation and heat dissipation.

Optics and shielding
The lamp proximity and orientation to unwanted cure surfaces influences the use of optics and shielding. Care should be exercised to ensure that UV rays are blocked from digital inkjet print heads, ink and coating pans, and heat-sensitive materials on the machine. In addition, all light should be shielded from direct line of sight with the operator.

Drastic part profile
Industrial applications with drastic part surface profiles, cure surfaces or manufacturing lines that require LED lamps to be mounted at greater distances (several inches or more), and the need for incredibly hard, scratch and chemically resistant UV LED top coats are still a bit of a challenge and should be considered in-development for the foreseeable future.

More recently, regulatory pressure to find alternatives to mercury vapor lamps, sustainability initiatives and a global energy crisis are driving more rapid adoption of UV LED curing systems and spearheading innovation within the chemical formulations. While development is ongoing, UV LED curing technology is becoming the preferred UV source in a growing number of applications. Despite the inability to use the exact same system interchangeably across applications and machine types, there do exist UV LED solution sets that meet the needs of many applications. While OEMs may default to an established LED curing device on new machines and retrofits, it always is recommended that end users confirm through testing or by referencing previous installations that the correct system was matched to the specific needs of the process. Follow the guidelines in this article and work closely with the UV LED curing system supplier, formulators, OEM machine builders, integrators and end users to ensure greater overall UV LED curing success.

Jennifer Heathcote is a subject matter expert on mercury vapor and LED UV curing systems as well as their use across a broad range of graphic arts, product decorating, and industrial coating and converting applications. Heathcote earned her Bachelor of Science in Mechanical Engineering from Purdue University and her MBA from the Fisher College of Business at The Ohio State University. Heathcote is a current board member of RadTech North America and is VP of business development at GEW, Inc. For more information, visit www.gewuv.com.