Excelitas Technologies Utilizing deep-uv LED below 300nm to enhance curing

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2 Excelitas Technologies Utilizing deep-uv LED below 300nm to enhance curing Dr. Tanja Bizjak-Bayer Business Development Manager, OmniCure

3 Who We Are Lumen Dynamics was acquired by Excelitas Technologies Corporation in November 2013 Excelitas has over 5,500 employees worldwide Global network of design and manufacturing locations in the Americas, Europe and Asia 3 facilities for LEDs (USA, Canada, Germany) > 40 yrs. of LED experience incl. CoB capabilities > 30 yrs. of experience with UV systems Over 35,000 UV curing systems currently being used in more than 50 countries Mississauga, Canada (Toronto)

4 Technology Required for Curing Process UV Curing Process RADIOMETRY

5 UV LED for Curing Applications UV LED curing systems have many functional advantages over lamp-based systems Longer life, reduced energy, lower heat, lower maintenance, instant on/off, Hg free Formulation modification has enabled the use of many UV LED curable materials in commercial applications Digital print, electronics assembly, optical bonding, medical device manufacture

6 Custom optics for various working distances Irradiance for AC8 Series Standard Version Irradiance for AC8 Series Print Version 1mm 10mm 30mm Standard versions with lens optimizes for longer working distances Print versions achieve higher irradiance at short working distances Strong focus to get extreme irradiance in smaller area

7 Multi-zone Irradiance Control LED building blocks LED Arrays made up of multiple smaller modules Patented technology to allow for individual control of modules Increase flexibility Increase homogeneity and cure widths Customize output profile

8 What is UVC?

9 Ozone is not an issue Ozone is created by oxygen gas absorbing light then cracking and rebonding into ozone which only happens below 242 nm (max at 180 nm)

10 Evolution of UVC LEDs LED efficiency and lifetime continue to improve at a steady rate Technology breakthroughs 2014/2015 Increased R&D spending Many new deep UV manufacturers Multiple wavelengths available 265 and 285 nm initially selected * Source: AquiSense Technologies, July 2015

11 The UVC System Challenge UVC die limitations More heat than light <10% external quantum efficiency Greater non-radiative recombination associated with defects in the die Difficult to extract light System designer must evolve Cutting-edge LED packaging materials & methods Innovative thermal management techniques Advanced light collection and delivery optics every photon counts

12 First Cure Trials Performed 285nm pre-packaged LED array Very low Irradiance achieved: <100mW/cm 2 Multiple adhesives & conformal coatings selected for trials Samples exposed to UVA/UVV LED radiation with a UVC LED post cure

13 Evaluation Method Selection criterion Adhesive and conformal coating samples that were difficult to cure with commercially available 365nm and 395nm light sources Relevant to commercial opportunities A scale between 0 and 5 has been adopted 5 is tack free (hard/strong surface; the best surface cure achievable) 4 is tack free 0 is wet surface 0 < 1 < 2 < 3 < 4 < 5 Verification of results A UVC lamp was used to determine irradiance threshold needed to impact surface cure

14 Dose (J/cm 2 ) Experimental Results - Adhesive Addition of UVC allows for significant reduction in UVA dose while still achieving equivalent surface cure Surface Cure Rating UVA UVC 0 A A1 B B1 B2 Sample #

15 Initial Experimental Results Large UVA/UVV dose still left a wet surface Improved surface cure was achieved with addition of UVC LED exposure Addition of UVC allows for significant reduction of UVA/UVV dose Able to achieve same surface finish

16 Dose (J/cm 2 ) Experimental Results - Coatings Two dual cure coatings Samples C + D 60 Surface Cure Rating UVA UVC 0 C C1 D D1 Sample #

17 Initial Experimental Results Dual Cure Coatings Large UVA/UVV dose still left a wet surface Secondary cure mechanism provided hard surface after 6 12 hours Addition of UVC provides improved surface cure with significant reduction of UVA/UVV dose Not always able to achieve acceptable surface finish

18 Next Generation UVC System Efficiency of UVC LEDs continues to increase Now available in bare die More flexibility for system design improvements Latest system 700mW/cm 2 278nm CW UVC System Irradiance UVC System Spectrum

19 Dose (J/cm 2 ) Wavelength Effect Previous Results nm A B C D Sample #

20 Dose (J/cm 2 ) Wavelength Effect Lower Wavelength May be able to reduce dose and / or improve surface finish with shorter wavelength, higher irradiance nm 278nm 0 A B C D Sample #

21 New Testing: Commercially Available Coating for Plastics 16 Surface Cure Rating UVA E F

22 Dose (J/cm 2 ) New Testing: Commercial Coatings Surface Cure Rating E E1 F F1 Sample # Addition of minimal UVC dose (200mJ/cm 2 ) improves surface finish with lower total dose required 5 UVA 278nm

23 Dose (J/cm 2 ) New Testing: Experimental Coatings 0,6 Surface Cure Rating 0,5 0, ,3 0,2 0,1 5 5 UVA 278nm 0 E1 F1 G1 H1 Sample # New coating formulations may be able to reduce UVC and total dose requirement even further - 20mJ/cm 2 UVC improves surface finish

24 Is LED an Option for Surface Cure? We know short wavelength UV is useful for improving surface cure < 350nm is required Commercially available UV LED curing systems currently do not cover the UVC spectrum UVC LEDs now available from multiple manufacturers Opportunity to benchmark technology Current LED curing solutions lack UVC Post cure or in line exposure to deep UV LEDs is an attractive solution to achieve surface cure taking full advantage of LED benefits.

25 Further UVC-LED Benefits Improved Surface Cure Short wavelengths rather staying at the surface than penetrating the depth Less (UVA) LED dose needed In combination, UVA can be used at much lower dose Decreased Yellowing? 280 nm far away from visible (blue) light Allows simpler formulation approaches for LEDs? Utilizing formulations used for regular UV lamps Low migration formulations? Less VOC? Due to the use of suitable chemistry at 280 nm

26 UVC-LED Testing Verify/Falsify expected benefits Surface Cure, dose and YI reduction, low migration, etc. Application specifics Differences in coatings, inks, glues, lacquers, etc. Dependence on Pis, resins, pigments and other ingredients Prepare the Future 280 nm will become commercially feasible in a few years Cooperation in Technology and Marketing Working on the solution together with other players

27 Trials Summary Achieved or overachieved the expectation Clear Coatings on metal packages (tubes, cans, etc) Pigmented inks and white colors for printing (Flexo, Offset) Overprint varnishes for Flexo- and Offset print Glossy surface at Inkjet print Various mixture of Resins and PI for different Applications Wood coatings On a way from the laboratory to the market

28 UVC-LED Status Power / Efficiency Lifetime Commercialization (Curing) Irradiance Price

29 The Path Forward Rapid advancement in core technology Improved power output (>10x in last few years) Increase current densities & lifetime Decreasing LED die costs as yields improve Commercial success will depend on advanced system design optimized for the application Balance cost vs. performance Wavelength selection Further cure trials

30 Many Thanks to the Partners who make the firts steps in testing the OmniCure UVC LED device

31 Thank You Questions? Come visit us at Booth # B.23 Jörg Hannig & Tanja Bizjak-Bayer Tanja.Bizjak@excelitas.com Joerg.Hannig@excelitas.com 31

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