PCC and SuperCorona improve quality Unique GEMA technologies to reduce powder overcharging Improve penetration, reduce orange peel, back-ionization and picture frames even with difficult powders. Ideal powder charging Improved application quality © 2015 by Gema Switzerland GmbH - All rights reserved. Improved powder penetration

Electrostatic powder coating ● Today’s powder coaters need to use a wide variety of powders, with different formulations and characteristics. ● Only the ideal charging of each powder ensures perfect coating results. ● Gema is offering innovative technologies to achieve the ideal charging of even challenging powders like structured and metallic powders, porcelain enamel, 2-coats 1-fire powders, etc. © 2015 by Gema Switzerland GmbH - All rights reserved.

Powder charging: how does it work? ● In a corona gun the high voltage electrode generates a big quantity of air ions ● Only part of the air ions really charge the powder particles, the other ions remain free and are attracted by the surface to coat (which is grounded). ● The accumulation of free ions on the surface to coat can produce an uneven powder layer and the so called “orange peel effect” or “back-ionization” problems. © 2015 by Gema Switzerland GmbH - All rights reserved.

Ideal powder charging ● Most powders need the gun to deliver a high level of charging current in the region of 10 to 100 µA. ● Special powders (metallic, enamel, two coat / one fire powders) are high-chargeable and require the guns to deliver a lower and well controlled charging current, below 10 µA. ● The precise charging PCC technology or the SuperCorona add-on are the ideal solution to provide the right amount of charges needed by each powder type ● This results in a much more efficient charging process and improved application quality. © 2015 by Gema Switzerland GmbH - All rights reserved....

Precise Charge Control: how does it work? Solution for high-chargeable powders 0.5 to 10 µA Traditional Charging: less precise, low resolution Precise Charge Control (PCC): more precise, high resolution In traditional corona guns the regulations of the electrostatic parameters are not very precise. Gema has developed PCC, an electronic technology that allows more precise electrostatic regulations. The actual value of the charging current can vary within a significant range in comparison to the set value. The electrostatic parameters are kept within a much smaller variation band in comparison...

Precise Charge Control activation ● Precise Charge Control (PCC) mode is automatically activated when Current is set below 10 μA. ● The OptiSpray display showing the High Voltage and Current control turns red when PCC mode activates. © 2015 by Gema Switzerland GmbH - All rights reserved.

SuperCorona: how does it work? Solution for low-chargeable powders 11-100 |jA In a corona gun the high voltage electrode generates a big quantity of air Only a few air ions really charge the powder particles, the other ions remain free and are attracted by the surface to coat (which is grounded). The high accumulation of free ions on the surface to coat can produce an uneven powder layer and the so called orange peel effect" or back-ionization" problems. SuperCorona discharges the excessive free ions to ground and avoids Traditional Charging with SuperCorona © 2015 by Gema Switzerland GmbH -...

Improved surface quality ● Orange peel effect and back-ionization can happen when the guns are emitting too much charges. These charges accumulate on the surface to coat and create visual defects. ● PCC technology and SuperCorona help to optimize the amount of charges that are needed by each powder. ● Advantages: o much nicer surfaces, o even with special powders, o even when high film thicknesses are needed © 2015 by Gema Switzerland GmbH - All rights reserved.

Improved powder penetration Powder penetration into corners is difficult because of the Faraday Cage The electric field (created by the electrode and by the charges) pushes powder particles to the edges of the object, while the electric field is not getting into the corners. reduce the electric field generated by o Easier penetration into corners o More regular powder distribution Traditional charging © 2015 by Gema Switzerland GmbH - All rights reserved.