Electrostatic Charge on Paper

Printers are familiar with the problem: printing sheets stick together because they are electro statically charged. The result: several sheets are simultaneously sucked in from the stack, stopping up the feeder. Static electricity arises from either an electron deficit (positive charge) or an excess of electrons (negative charge) on the surface of the paper. An electrostatic charge is especially likely to occur when paper that is too dry is processed under conditions of low atmospheric humidity. The critical lower limit - as much for paper dampness as for relative humidity - ranges from 40% to 42%. (Electrostatic = immobile, i.e. static electricity)

Remedy:

• The moisture content of paper should range between 45% and 55%. The electrical conductivity of paper, and consequently electrical run off, increases with increasing moisture content
• Working spaces should be air-conditioned or humidified at a 50% to 55% level of relative humidity. Particularly during colder times of the year in heated rooms, the atmospheric humidity can sink dramatically
• Antistatic equipment such as discharge electrodes and ionic blowers reduce electrostatic charge; ionization equipment raises the surrounding air's electronic conductivity, thereby preventing the build up of static charge