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7 2007 PLACE Conference September St Louis, MO Nano-Composite Polymer Optical Coatings Vampire Optical Coatings, Inc. Tom Faris

8 Introduction What is a nano-composite polymer coating? Our Definition: A coating that has some volume fraction of inorganic nano-particles dispersed within the coating, such that, the physical, optical and/or electrical properties are modified. Also known as a ceramer (i.e. a ceramic polymer) Types: Si0x modified coatings abrasion resistance improvement (2 to 3x) Antimony tin oxide/indium tin oxide modified coatings selective transmission/heat rejection coatings Electro-static dissipative coatings Zirconium oxide modified High refractive index coatings Index matching coatings

9 Introduction Reflectance Light transmission = LT Reflectance = R Comprised of specular and diffuse reflection R(%) = %R (specular) + %R (diffuse) Absorbance = Abs %LT = R(%) Abs(%) Fresnel Reflectance i.e. mirror like R(%) per side = ([(η d 1)/(η d +1)] 2 )*100 Diffuse Reflectance Light scattered more than 2 degrees from the observer angle (ASTM D1003)

10 Introduction Why does reflectance matter? Reflectance reduces the contrast of a display Decease in readability of display Lower black level & higher background noise Conductive traces in projected capacitive displays very apparent against non-conductive areas Exacerbated as number of interfaces increases Interfacial Reflectance Happens every time refractive index changes Proportional to change in refractive index

11 Introduction How is a display s s contrast improved? Anti-Glare film Comprised of an irregular surface that scatters reflections Reduces specular reflectance Increases diffuse reflectance Anti-Reflection Film Multi-layer layer vacuum deposited dielectric materials Destructive interference of light Excellent performance, very expensive due to slow rates and ultra vacuum requirements Wet Applied low reflectance coatings Good performance, lower cost (fluoro coatings) Index Matching coatings (touch panels) Vacuum deposited dielectric multi-layers layers Reduces R(%) & increases LT (%) Excellent performance, expensive due to slow rates and ultra vacuum requirements

12 Introduction Production techniques Vacuum deposited AR (Sputtering, PVD, PECVD(?)) Requires an ultra vacuum Slow rate due to thick layers of inorganic oxides Requires additional anti-smudge layer Sol-Gel Dip Deposited Anti-Reflection Large tanks with low usage rate Vibration sensitive Additional anti-smudge layer necessary Low refractive index fluoro monomer/polymer Atmospheric production using traditional roll-to to-roll wet coating techniques Anti-smudge layer inherent Adequate performance with lower cost (~1/3 vacuum)

13 Figure 1: Resistive Touch Panel Reflections R1 = 5.0% R2, R3 = 10 to 12% R4 = 5.0 % R total = ~ 30 % of ambient light R1 R2 R3 R4R5 PET film ITO display

14 Table 1: Nano-Particle Coating Dispersions & Properties Coating Wt% nano- particle Metal Oxide Type VHx 80.0 Zr0 2 mixed Size (nm) Appearance 20 Dry coating is shiny & clear Refractive index (550nm) Up to VHx-C 85.0 ATO 15 Clear gray/green VHx-S 55.0 Sb Dry coating is shiny & clear IM Si Clear IMESD ATO 15 Gray/Green 1.685

15 A Film Structure C 3.0 micron HC PET Film B ID A B C %LT %Haze %R(Y) %R %R avg(450 to 650nm) PET N/A N/A N/A 89 <1.00 >5.00 > S N/A IM002 (95nm) VHx (80nm) >93 < H MHC (95nm) Ti02 (18nm) VHx (102nm) >93 < <1.00 IMAR ITO (22nm) IM002 (45nm) VHx (75nm) >91 <1.00 N/A N/A LR N/A Fluoro (100nm) VHx (80nm) >

16 Results & Discussion High Refractive Index Coatings (VHx) HybridAR coatings (VAR 751H): Design: Air/UV acrylate/ti0 2 /VHx/HC PET VHx acts as buffer layer in design Provides broad band AR with only 1 sputtered dielectric layer Eliminates several thick sputtered layers Anti-fingerprint layer step eliminated High abrasion and chemical resistance Good adhesion of sputtered layers in VHx layers

17 Results & Discussion High Refractive Index Coatings (VHx) Index Matched ITO Coatings Design: Air/ITO/IM002/VHx/PET Light transmission is increased as compared to standard ITO coated film (>91.0% vs. mid 80 s) Comparable performance with vacuum deposited index matching layers Several thick vacuum deposited layers are eliminated Reduced cost of production Possible to selectively enhance transmission, minimize change in contrast between coated and non-coated areas

18 Results & Discussion High Refractive Index Coatings (VHx) Low Reflectance Coatings (VAR 1251S) Design: Air/IM002/VHx/HC PET High transmission Low reflectance (high reflected color) Excellent durability Simple construction

19 Results & Discussion Low Refractive Index Coatings (IM002) Si0x (20 to 40 wt%) in dry coating UV curable Abrasion resistant coatings High clarity, excellent abrasion resistance Low index coating for IMAR and 1251S Very thin layers possible High transmission, good uniformity Tunable surface energy multi-layer layer stacks possible Excellent adhesion of sputtered layers to IM002 AFP surface possible

20 Results & Discussion Other Coatings/Combinations Antimony Tin Oxide and/or Indium Tin Oxide Nano- Composites Infrared blocking filters/coatings Absorption based Multi-layer layer reflective heat mirrors (55 % reflectance at 950nm) Electro-Static Dissipative Coatings (ESD) >10(7) Ohms/square High Abrasion resistance Permanent ESD 8/25/2007

21 Conclusions Nano-Composite Polymer Coatings Are useful as substitutes for or as. Compliments to vacuum deposited inorganic metal oxides Facilitates substantial productivity improvements Uses conventional roll-to to-roll wet coating equipment Coated materials produced, to date, exhibit excellent optical properties, mechanical properties and temperature/humidity resistance.

22 QUESTIONS?

23 Vampire Optical Coatings, Inc. Tom Faris Thank You Please remember to turn in your evaluation sheet...