For ignition coils, that are working at high voltage value, even micro bubbles are very dangerous for its life. If the resin filling isn’t perfect, it’s possible to have high partial discharges values. The vacuum dispensing is necessary in order to obtain a very high level of insulation, and Demak provides it. The vacuum casting chamber, that is fundamental for this process, can be easily integrated on full automatic lines. The vacuum is crucial to avoid any air bubble presence in the insulating resin. In order to perform a perfect process, the resin must be pre-treated and cast at high temperature, therefore the best resin to be used is epoxy with anhydride based hardeners, having high Tg value and excellent thermal conductivity properties.