EXAIR Eliminates Static – Public Enemy Number one in the Printing Industry

Static electricity is the enemy of the printing industry. Downtime and inefficiency caused by static means longer lead times and angry customers! EXAIR can remove static electricity in the many printing applications across wide and narrow webs.  With our rugged line of EXAIR Super Ion Air Knives and Ionizing Bars, EXAIR can improve your efficiency and printing quality.

Digital printing dries out the printed substrate, creating high static charge that can cause printing defects, ink overspray, and even print head clogging and print head shorting issues. If a press is printing on non-porous substrates like plastic, metallics and highly coated glossy papers, a device called a corona treater is used to increase the surface energy of the substrate to ensure the ink droplets adhere and do not spread too much on the substrate. A byproduct of the corona treatment is static charge, which must be removed. This can be achieved by installing an EXAIR Ion Bar after the corona treatment device across the web.

Static is also created anywhere in the printing or finishing operations where sheets are moved over each  other.   Sheet-fed presses, for example, create friction in the stacking of individual sheets on top of each other.  This friction induced static creates misfeeds, print registration issues, multiple sheet pickups and equipment jams.

Folding operations cause static issues too. Like a sheet-fed press, static is created by folded pieces being dragged across each other.

In both cases, installing an EXAIR Super Ion  Air Knife or Ion Air Cannon that can direct a stream of ions between the stack and the top sheet can eliminate the static that causes misfeeds and jams.

The typical easy fix printers employ is what’s called a tinsel bar. Also called garland, it looks just like what you drape on a Christmas tree, except that it’s made of highly conductive copper that needs to be grounded to the printing press.The problem with tinsel bars is that although they are cheap initially, they don’t last long. They’re not a set-it-and-forget-it solution. The sharp strands work on induction and interact with the static field on the substrate creating a neutralizing cloud that surrounds the area, reducing both positive and negative ions. Printing operations are usually dusty environments and when the tinsel becomes dusty, oxidized, or matted and crumpled, they don’t work as effectively.

Static is also created in unwinding and rewinding operations, when rolls are slit to needed widths of various presses. The removal of the web from the roll creates static charge that attracts dust to the substrate surface and can cause major problems in downstream printing operations. Installing an EXAIR Ion Bar on top of the web can eliminate this static.

EXAIR Super Ion Air Knives don’t need to be placed close to the surface like a tinsel bar. Static dissipation of 5 KV can occur in less than a half second up to 20 feet away and can be adjusted from a blast to a breeze, depending on static level.

If you are a printer, finisher or labeler, EXAIR has a static elimination product that can improve your operations. For more help you can contact one of our EXAIR application engineers to talk you through a solution.

Dann Woellert
Application Engineer
dannwoellert@EXAIR.com
@EXAIR_dw                    

 

 

 

EXAIR Static Eliminators Remove Static Issues for Multiple Label Printing Process

Recently, I visited a local customer to look at a specific application. This company prints over 146,000 different labels on plastic film, paper and foil. They called because they were seeing several different static related issues during printing and stacking processes.

On their first application, involving a 60″ wide sheeter, they were having an issue with irregularities as the sheet travels over several rollers where it enters the print head of the machine, then is cut and stacked. At the time of the visit, they were using a competitor’s product after the printer but those products were not effectively removing the static. We were able to determine they were not working by using  our Digital Static Meter which told us there was still a 2.7 kV charge after the treatment area. I recommended the customer replace the ineffective units with our 60″ Ionizing Bar. The Ionizing Bar produces a bulk of positive and negative ions to eliminate the surface static of an object when mounted within 2″ of the surface of the material. The bar features a mounting flange that would allow the customer to use the existing bracket for easy installation.

Ionizing Bars Work
Ionizing Bars – available from 3″ – 108″.

The second machine we looked at was a 42″ 3-sheet press. Our readings ranged from 4.2 kV on the top sheet, 1.4 kV middle sheet and 9.9 kV on the bottom sheet going into the press/print head and around 15.6 kV at the discharge. This unit also had another anti-static device taped in place but was clearly no longer operational. I again recommend the Ionizing Bar for this application as well. After speaking with the operator, he was saying he was also seeing an issue with the sheets lifting and trying to separate as they were being stacked. To remedy this problem I recommended using our Super Ion Air Knife at low pressure to blow ionized air from behind the sheet to help it float onto the stack and remove static at the same time. The Super Ion Air Knife is our Super Air Knife with the Ionizing Bar attached and is capable of dissipating 5kV in less than half a second.

Super Ion Air Knife
Super Ion Air Knife provides laminar sheet of ionized air across the length of the knife.

Lastly, we looked at their smaller sheeting machine and on this unit we were seeing around 3.5 kV as they stack was fed into the feeder and 7-8kV at the end stacker. At the beginning of the process we noticed the customer was using an air blowoff on each side of the sheet stack to assist with lifting and getting some separation between the sheets for the mechanical lifter to feed the machine. At this area they were experiencing some issues as occasionally the lifter would pick up more than 1 sheet and cause a jam which shut the system down. It turns out the airflow across the sheets was actually generating a slight static charge as we were seeing higher readings around 4.2 kV. Since they were already using air, I recommended replacing these blowoffs with our Ion Air Jet. This would aid in reducing the static and result in a more effective separation between the sheets allowing for a cleaner lift. For the sheet itself, we would recommended the Ionizing Bar if they were able to mount within 2″ or the Super Ion Air Knife for further mounting distance.

NEW Ion Air Jet
Ion Air Jet produces concentrated ionized airflow.

 

We realize we can’t look at every customer’s process but any photos or videos you could share of your application, we would gladly review and make a possible recommendation. Please contact one of our application engineers for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN