A high static charge can generate a mirror image of the charge with reverse polarity on a surrounding element.
We can illustrate this with the example of the ball that the child rubbed (therefore loaded) and then escaped. This balloon will stick to a wall.
The negative charge of the balloon creates a positive mirror image on the wall and the attractive force due to the differences in polarity causes the two elements to attract and the balloon sticks to the wall.
Two principles of electrostatic attraction are fundamental for the industry and its applications:
2 electrostatic charges of opposite polarity
At least one of them must be active – the generator bar 7080 – the other can be active or passive.
The force of attraction is explained by Coulomb’s law:
attraction = (charge1 * charge2) / distance2
The additional factor that is required is a barrier to stop the two attracting charges. In practice, the barrier is made of plastic or a non-conductive material. If the barrier is not insulating, it will allow current to flow from one charge to another, thus allowing their neutralization. When it is insulating, it will retain the charges and therefore “stick” to one of the elements.
The plastic film barrier (towards the arrow) retains the positive charges by basing (sticking) on the metal part.
Plastics are good barriers because they are non-conductive. Paper is more complicated because it is conductive, especially in conditions with low humidity. The paper must have a surface resistivity of at least 1010 Ohms / m2.
Our “740 SRM” surface resistivity meter is essential for measuring the suitability of materials such as paper.