Conductive varnish
Conductive lacquer is electrically conductive lacquer that is mainly used in electronics.
The electrical conductivity is generated by a very high proportion (up to 80% and more) of conductive filler materials in the paint matrix. The individual grains are in contact with each other and thus enable the flow of current.
composition
Conductive ink, there are based on silver - ( silver conductive or conductive silver ), copper - (conductive copper) and graphite particles (Graphitleitlack).
The binder component can be a one - component, solvent-based paint or a synthetic resin (one or two-component). The resins in particular can also be used as conductive adhesives .
application areas
With conductive varnish, for example, you can repair defective conductor tracks on circuit boards by bridging or connecting them again. This is particularly helpful with printed flexible circuit boards, but only suitable for low currents. According to the manufacturer, the electrical sheet resistance of a dried layer is usually around 20 to 100 mΩ. For comparison: the sheet resistance of the copper on the circuit board is around 0.5 mΩ, which is around two orders of magnitude lower.
Also one broken with conductive paint can rear window heaters of car repair.
Conductive lacquer can be used to contact temperature-sensitive electronic components and is an alternative to soldering when the currents are low.
In particular, silver-filled conductive lacquers have excellent thermal conductivity in addition to electrical conductivity . This effect can be used when mounting the heat sink on processors and other components with high power dissipation , see also thermal paste .
Conductive lacquers are used to produce conductive coatings, for example for shielding electrical fields. Examples are the inner coating of plastic housings for electronic devices and components or the outer coating of electron tubes. Another industrial application is the production (printing) of bridges on (mostly single-layer) printed circuit boards after a layer of insulating material ( solder mask ) has been applied to the conductor path to be overcome.
source
- ↑ Article sheet resistance