Pile Blocking (Offset)

Abstract:

Pile blocking is a major print-process problem that results in solidly blocked piles or rolls (web offset). In most cases, pile-blocking will be noticed by the postpress first. Pile blocking normally appears only when sheets are coated using double-sided gloss coating or when printing on plastic stock.

Suspect 1 – Pile temperature too high

Excessive substrate temperature will make the surface of inks and coatings tacky so the may stick on each other

Redeem:

  1. Reduce the pile/roll temperature to the very minimumUse hot air and hot-air-exhaustion instead of Infrared (IR)

 

Suspect 2 – Too less or no Anti-Set-Off-Powder

Anti-Set-Off-Powder in between the sheets may prevent the superposed material-layers from sticking to each other. Also, additional air between the layers may improve the drying and cooling-down process.

Redeem:

  1. Add and adjust applied powder quantity to the maximum applicable level for the given print job

Suspect 3 – Wrong type of Anti-Set-Off-Powder

There are 2 different types of powders available. Silicone-treated powders for use in combination with water-based coatings and untreated ones for non-coating applications and the use of UV-curing inks.

Redeem:

  1. Apply the correct type of powder and granularity for your application

Suspect 4 – Static Substrate

If the substrate gains electrostatic load while the printing process, temporarily pile blocking is given an advantage

Redeem:

  1. Let printing stock settle and adjust to pressrooms air-conditions before printing
  2. Turn ON antistatic devices options of your press (if available )
  3. Turn OFF static loading devices in the delivery (typically used to keep anti-set-off-powder sticking t the substrate)
  4. Try a different type of blankets

Need support for your individual case?
Contact us now!

More Press Troubleshooting Tips:

Pile Blocking

How to address blocking piles after press delivery (Offset)

Framing

Picture Framing. An printing issue were ink is getting transferred over non-printing area

Ink Misting

Ink misting. Dirty printing presses caused by Ink-Aerosoles.

Coating Chamber Leaking

How to address leaking/slinging coating units in industrial printing machinery.

Streaking (Offset)

Streaks in print are color density fluctuations or contrast variations, usually perpendicular to the print direction.

Piling

  Abstract Piling is an unwanted effect, where the pigments of the ink build-up negatively on the blankets. Serious...

Offset Ink Drying Issues

Abstract: While drying, conventional offset inks dry by evaporating volatile components (solvents) into the...

Ink Misting

Ink misting. Dirty printing presses caused by Ink-Aerosoles.

Framing

Picture Framing. An printing issue were ink is getting transferred over non-printing area

Piling

  Abstract Piling is an unwanted effect, where the pigments of the ink build-up negatively on the blankets. Serious...

Coating Chamber Leaking

How to address leaking/slinging coating units in industrial printing machinery.

Pile Blocking

How to address blocking piles after press delivery (Offset)

Offset Ink Drying Issues

Abstract: While drying, conventional offset inks dry by evaporating volatile components (solvents) into the...

Streaking (Offset)

Streaks in print are color density fluctuations or contrast variations, usually perpendicular to the print direction.

Pile Blocking

How to address blocking piles after press delivery (Offset)

Piling

  Abstract Piling is an unwanted effect, where the pigments of the ink build-up negatively on the blankets. Serious...

Ink Misting

Ink misting. Dirty printing presses caused by Ink-Aerosoles.

Framing

Picture Framing. An printing issue were ink is getting transferred over non-printing area

Coating Chamber Leaking

How to address leaking/slinging coating units in industrial printing machinery.

Streaking (Offset)

Streaks in print are color density fluctuations or contrast variations, usually perpendicular to the print direction.

Offset Ink Drying Issues

Abstract: While drying, conventional offset inks dry by evaporating volatile components (solvents) into the...

Ink Misting

Ink misting. Dirty printing presses caused by Ink-Aerosoles.

Framing

Picture Framing. An printing issue were ink is getting transferred over non-printing area

Coating Chamber Leaking

How to address leaking/slinging coating units in industrial printing machinery.

Offset Ink Drying Issues

Abstract: While drying, conventional offset inks dry by evaporating volatile components (solvents) into the...

Piling

  Abstract Piling is an unwanted effect, where the pigments of the ink build-up negatively on the blankets. Serious...

Streaking (Offset)

Streaks in print are color density fluctuations or contrast variations, usually perpendicular to the print direction.

Pile Blocking

How to address blocking piles after press delivery (Offset)