Controlling Static in Industry

+44 (0) 1398 331114

Graphical Digital Printing

Static neutralisation to protect print quality
Static neutralisation to protect print qualityNeutralise static on acrylic sheetNeutralise static charge in digital printing







Graphical Digital Printing

Digital printing is susceptible to static charge in many ways, both in graphic colour work and document printing.  These notes concentrate on the graphics side of the market.  The two most common static problems here are:

Dust Contamination:  Mainly on rigid plastic substrates, especially when the protective film is removed.

Printing Quality:  Image distortion and shading on non-image areas when using UV inks.

Removing the protective film from a plastic sheet can generate a charge in excess of 50,000V.  This can attract airborne dust from over 1 metre away.  The resulting contamination of the product can be very expensive.

The most versatile and economic solution is the 4125 Ionised Airgun which not only removes the dust but also kills the charge, preventing re-attraction of the dust.

It is important that this operation is performed correctly.  If the sheet is large, the operator naturally lies it on a table, pulls away the backing strip and then cleans it with an Ionised Airgun.  This will have only a limited effect in neutralising the charge.  For best results the sheet should not be lying on the bench.  When the sheet is on the bench the charge couples with it and is not available to be neutralised.  If the sheet is not touching another part the charge is available to be neutralised.  

There are alternatives to using a 4125 Ionised Airgun, especially where the process is automated.  Options include:

  • Ionised Air Nozzles and Airknives to clean and neutralise,
  • Or our Ionstorm  long range static eliminators to neutralise the charge.

When a charged sheet is in free air the electric field radiates in all directions and is available to be neutralised.

When the sheet is flat on a bench the electric field couples with the bench and is not available to be measured or neutralised.


flat acrylic sheet 

The wrong way

With the sheet lying flat on the bench the 4125 Ionised Airgun is not being allowed to do its job efficiently because the charge in the sheet is Coupled with the bench.  With very large sheets it is difficult to hold them in free air, but dramatic improvements will be seen if the customer can hold the sheet as shown below, or put it on a vertical jig for cleaning with the Gun.


4125 neutralizing foam sheet 


The right way.

For effective cleaning and neutralisation hold the sheet in free air by tilting it on the bench or holding it in a vertical jig.


Printing Quality Problems

The electric field from the static charge can distort the imaging process causing various quality problems.

There are 3 ways of  solving this:

    1.  Use two 1250-S Static Eliminators, one on each side of the printing head, as shown in the photo.  The Bars should be angled 20-45° from the vertical for maximum effectiveness.  The Power Unit can be mounted on the Head (it weighs 2kg) or longer cable can be specified on the Bars for routing along the caterpillar track.
    2.  One Long 1250-S Bar can be positioned beneath the gantry on some designs of machine to cover the whole width of the printing area.  The Power Unit can be mounted on the side of the machine.
    3.  One or two Ionstorm bars can be positioned above the bed to shower the whole area with ionised air.  This neutralises the static charge without any mounting of equipment on the printer.



 Couldn't find what you were looking for? Try the Related Products below 


Related products

Related Products

Results 1 - 3 of 3