Conference Program

P: (240) 497-1242

RadTech International North America
The Association for Ultraviolet and Electron Beam Technologies
6935 Wisconsin Ave, Suite 207
Chevy Chase, MD 20815

UVC LEDs: A Reality Check

Robin Wright, Wright Way UV Consulting LLC

Long wavelength UV LEDs are widely being accepted by printers and other industrial curing markets. However, surface curing of free-radically polymerized coatings in air continues to be a challenge. As UVC LED technology continues to advance, there are no guarantees that what will be commercialized will overcome oxygen inhibition. This presentation will describe today’s reality and what I perceive as the issues and should be the concerns. A possible optimal solution for today’s environment will be presented.

Material Properties of UV Cured Composites

Jon Shaw, Allnex

Composites are generally cured at elevated temperature for relatively short periods of time, or at ambient temperature for longer periods of time, or through some combination of the above. Employing Ultraviolet (UV) energy to cure composites offers a styrene-free, fast and one component alternative to current composite manufacturing processes. One challenge to using UV energy is to cure very thick parts, since the UV energy is attenuated as it passed through the fibers. Different strategies for thick cure, such as dual cure, cure while winding or LED curing will be compared. Advances in renewable and bio-based materials will be highlighted.

Direct Chemical Characterization of Food Packaging Prints

Luke Lindahl-Ackerman, FDA

Although packaging plays a central role in food preservation and microbial safety, concern has been expressed surrounding chemical food safety, especially from packaging. Most modern food packaging and materials are chemically complex, layers of different polymers, adhesives, papers, foils, and invariably, prints. As the concentration of a single package configuration or formulation gets diluted in the marketplace, the chemical diversity expands. Chemical characterization of these modern food contact materials is an ongoing required task that provides data to inform safety concerns. To that end we utilized techniques such as non-targeted analysis, high resolution mass spectrometry, direct or surface mass spectrometry, and more traditional ultra high performance liquid chromatography and gas chromatography mass spectrometry analysis. These techniques (including migration tests) were used to: 1. Determine if direct mass spectrometry could identify food packaging prints, additives, and components; 2. Directly and quickly detect photoinitiator set-off on retail food packaging; 3. Identify as many ink and packaging related components as possible present on the food contact surfaces of food packaging; and 4. Determine the incidence of photoinitiators on the food contact surface of retail food packages.

UV + PVD: Performance and Design Solutions

Eileen Weber, Red Spot Paint & Varnish

Interest in alternatives to electroplated chrome continues to expand. Environmental concerns and restrictions on the use of hexavalent chrome along with expanded appearance and design capabilities has made PVD technologies more attractive. Color, appearance and functional effects are limited with traditional chrome electroplating and successful paint on chrome applications is expensive and highly proprietary. Collectively, many markets including automotive, home appliance and cosmetic are actively searching for an alternative with the appearance and durability of electroplating, but without the environmental side effects, appearance limitations, and costs associated with this decades-old process. “Chrome look” processes and coatings for decorative and automotive lighting PVD applications have been used in the UV curable coating industry for over twenty years. As development of UV curable coatings for PVD has progressed, understanding of the PVD process and its unique capabilities and applications has also progressed. Color and appearance enhancements for chrome look parts can be achieved in many economical ways to include metal layering and tinted UV topcoats. This presentation will address the advantages of PVD as a chrome alternative to include functional / design capabilities that are either cost prohibitive, or impossible to achieve with electroplated applications.

New Electron Beam Equipment for curing digital inks, and or laminating adhesives

Im Rangwalla, ESI

Coming soon.

E-Beam Curable Resealable Adhesives: New Developments in Structure, Property, Processing Relationships

Jon Scholte, Sartomer

Resealable adhesives, which show little or no tack and only stick to themselves, are a current interest in the flexible packaging industry. These technology can be an alternative to mechanical zipper closures, which can have high costs associated with them. Our work has focused on resealable adhesives that can be processed by electron beam (E-beam) sources. E-beam processing offers the benefit of longer resin shelf life and the potential for fewer migratable components. This presentation will discuss our findings on structure-property relationships with regard to both processing and formulation for E-beam curing. Moreover, these relationships will be evaluated for their ability to tune tack and self-sealing ability of the adhesive.

UV+EB is the BIG IDEA in Regulations

Rita Loof, RadTech

Coming soon.

UV Processing of Advanced Polymer Materials for Energy Conversion and Storage

Prof. Ian Hosein, Syracuse University

UV curing is widely used to develop materials for applications such as thin-films, coatings, printing, graphic work, dentistry, contact lenses, and electronics. It is a noncontact, low-energy, and rapid proqcess with capabilities of spatially specifying the reaction via photomasks (i.e., photolithography). The versatility of UV irradiation enables it to prepare a broad range of polymeric and composite materials. In this talk, I will present our work on leveraging UV curing to develop advanced structured materials for energy conversion and storage. We first prepare polymer thin-films with light-guiding properties, and show how their coating of a solar cell surface greatly increases solar energy capture and conversion over the course of a day and across seasons. We then prepare thin-films possessing excellent ion transport capabilities towards the manufacturing of solid-state batteries with high capacity and thermal stability. These results reveal the potential for UV processing to play a critical role in next-generation materials development to provide significant advances in important applications.

Plasma – Plastic – UV-Cured Powder Coating

Andrew Walton, Keyland Polymer and David Foote, Nordson/MARCH

Plastic and composite substrates in the transportation and consumer goods environments face extreme environmental conditions, which can affect their reliability. Coatings are used to protect them, extending their longevity and offering aesthetic flexibility. This presentation will demonstrate how treating plastic and composite substrates with plasma changes the surface conditions enabling the use of UV-cured powder coating to finish these heat-sensitive substrates. The presentation will describe plasma treating, operating conditions, and surface measurements before and after plasma treatment. The second part of the presentation will describe adhesion results of UV-cured powder coating with and without plasma treating on various plastics and composites. To conclude, we will evaluate substrate material suitability for plasma treating, UV-cured powder coating and UV-cured powder coating performance characteristics.

Photoinitiators in a Waterborne World

Stephen Postle, IGM Resins

Waterborne uv-curable systems bring a number of well-recognized advantages, particularly, but not exclusively, with hydrophilic substrates, over 100% solids formulations, including rheology control in low viscosity systems like ink jet and the ability to coat very thin layers in wood and furniture coatings. There is growing usage of waterborne systems for 3D printing, too. But the large majority of photoinitiators available today are barely suitable, at best, for waterborne systems, having extremely limited water-solubility and/or major issues in forming a stable aqueous dispersion or emulsion. Fundamentally, to achieve fast polymerization rates and a high overall percentage cure in a uv formulated system represents a greater challenge in aqueous media. It is necessary for there to be intimate contact (solubility or equivalent) between the photoinitiator and the (meth)acrylate monomers and oligomers, for efficient initiation to occur. Matching solubility parameters between water, a surfactant, a monomer or oligomer and a photoinitiator is a challenge of a different order than formulating for 100% solids systems.

Aqueous dispersions of BAPO (e.g. Omnirad 819DW) and hydroxyalkyl alpha hydroxy ketones(e.g. Omnirad 2959) are two current solutions, both with shortcomings. We present here our novel and developmental approaches to these issues, covering water-soluble, water-compatible and monodispersed photoinitiators and offer some insights on the optimal acrylates to complement them.

UV Optical Elements for Horticultural Lighting

Justine Galbraith, Kopp Glass

The electronic components within a UV LED light system are fragile and expensive. It is vital to protect your investment from harsh operating environments. UV-transmitting optics are used to both protect electronic components and improve the radiometric performance. Although there are several UV- transmitting materials available, not all are equivalent for UV applications. This talk will discuss the performance considerations of various UV transmitting materials and how application challenges are addressed with the integration of a cover lens or optic for various UV applications such as horticultural lighting and UV Curing.

Developments in Laser Technology Enabling New UV Wavelengths in Compact and Highly Efficient Platforms

Chris Walton, Lumany

Today’s UV lasers are mostly third and fourth harmonic generations of Nd:YAG which continue to incrementally evolve. Recent developments in laser technology are delivering UV light via second harmonic generation, facilitating a much smaller footprint, simpler construction and new UV laser lines, such as 303 nm. These advancements are expected to enable applications including spot-disinfection and spot-curing based on their high intensity per unit area. Other potential application areas include test or reference sources in relation to other UV-emitting devices. A number of novel wavelengths, in conjunction with polymer development, are also expected to enable advances in printing and curing applications.