UV Product Range

Current UV Curable Range UV40 Performance and Benefits Technical information Comparisons Silicones and solvent based

UV Product Range Current UV Curable Range UV40 - Background Released in 2006 UV curable acrylated polyurethane chemistry Allows fast throughput for high volume production

UV Product Range Current UV Curable Range UV40 - Range UV40UV40-250UV40-100UV40-HVUV40 GelUV40 Solar Viscosity (cPs) Gel, Shear thinning 500 Application Methods Selective spray Selective spray, dip Selective spray Syringe dispenser Selective spray MarketsMilitary Consumer Automotive Consumer Micro electronics Any – for connectors etc CPV, LED

UV Product Range Current UV Curable Range UV40 range – Markets Automotive Consumer Military UV40 Range

UV Product Range Current UV Curable Range UV40 – distribution of sales Percentage of UV40 Sales

Performance and Benefits Technical information - Properties UV Product Range Can be applied with all selective coaters Electrical, physical, mechanical properties designed for current industry demands – VOC free, Pb free, no clean

Performance and Benefits Technical information – Comparison to Silicones UV Product Range

Performance and Benefits Technical information – Comparison to Acrylics UV Product Range

Performance and Benefits Technical information – Comparison to Urethanes UV Product Range

Performance and Benefits Explanation UV Product Range Increased material costs but 100% solids material Better all round performance – has benefits of urethane and acrylate chemistry Flexibility through only bettered by silicones – lets explain…

Performance and Benefits Physical properties UV Product Range Tg (°C) – Glass Transition Temperature. The temperature range at where it softens from a glassy to a rubbery polymer CTE (ppm/°C) – Coefficient of Thermal Expansion The dimensional response to a material upon changes in temperature

Performance and Benefits Test methods UV Product Range DMA Method - dynamic applies small deformation to a sample in a cyclic manner allowing the materials response to stress, temperature, frequency and other values to be determined. TMA Method - thermal Applies constant static force to a material and reports the material change as temperature or time varies to record dimensional changes. DSC Method Differential thermal analysis is the measurement of the difference in temperature between a sample and a reference as heat is applied to the system.

Performance and Benefits DMA trace example UV Product Range

Performance and Benefits Test methods UV Product Range Silicones typically have a Tg higher than RT – flexible at RT and increased operating conditions UV40 range Tg around RT (depending on test method) - will be glass-like at lower temperatures So during thermal shock cycles UV40 spends longer ‘glass like’ per cycle than silicone based

Performance and Benefits Thermal shock or thermal cycle? UV Product Range Thermal cycle = like Mil spec – slow ramp between temperature extremes. 100 cycles

Performance and Benefits Thermal shock or thermal cycle? UV Product Range Thermal shock = automotive specifications – fast ramp (40-60C/min) designed to ‘shock’ materials / solder joints FORD spec -45 to +85C 1000cycles Also depends on CTE mismatch between components (metals, plastics etc) and coating – test board also important

Performance and Benefits Material cracking through thermal shock UV Product Range Cracking has been observed with UV through thermal shock testing during customer qualifications Humiseal set up a in-house study to investigate the causes of cracking and mitigation strategies

Performance and Benefits Test board UV Product Range

Performance and Benefits Design of Experiment UV Product Range Selectively apply UV40 and UV to the test board and run thermal shock tests to investigate:  Thickness  Secondary curing - Rapid cooling of assemblies after oven curing  UV dosage Inspect at 20-40x magnification at intervals during thermal shock

Performance and Benefits Design of Experiment UV Product Range Thermal shock info: -65C to +125C, 30 minute each temperature, 5 minute transition between T1 and T2. (~40°C/min Rate of Change) →Inspect at 20-40x magnification at intervals in the thermal shock

Performance and Benefits Findings after 500cycles UV Product Range *UV40 and UV at 100µm

Performance and Benefits Explanation UV Product Range During cure processes chemical bonds shorten in length →This causes shrinkage in coatings On flat substrate not an issue because coating unrestrained When applied over 3D components it creates stresses within coating as it cures Stress has to be relieved  Can cause cracking Measured shrinkage of UV40 and UV at various cure conditions UV shrinks more than UV40  Higher stress within coating  Increased tendency to crack

Performance and Benefits Mitigation UV Product Range 1.Control Coating Thickness 2.Avoid Accelerated Secondary Cure Process 3.Proper UV Cure Conditions 4.Thermal Shock Conditions a.Higher rate of temp change increased tendency for cracks 5.UV40 vs. UV a.Less shrinkage during cure b.Lower incidence of cracking c.Tg = 45 vs 25C

Performance and Benefits Next steps – UV40 new UV Product Range Based on UV40 chemistry which has many excellent properties New UV curable will have increased crack resistance –  increased flexibility,  raise the Tg  match CTE closer to components Formulation and testing is under way – expected earliest release date late 2012

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