Offset printing glossary

WIT printing lexicon helps you understand the concepts you encounter in sheet-fed offset printing. Check each term’s meaning and recognise the symptoms. Gather the necessary information before selecting materials.

Select a topic. Each entry combines a short explanation with practical questions and links to offers and guides.

Offset inks: properties and printing behavior

• Tack and offset ink viscosity – Know the difference between layer separation resistance and flow resistance.
• Ink chalking – check why the pigment is rubbing off from the print.
• Emulsification of offset ink – distinguish the contribution of water in the ink from the loss of equilibrium of the process.

Stack problems: set-off and blocking

Set-off and blocking . Distinguish ink transfer between sheets from sheets sticking together. This difference guides your diagnosis.

Chemistry and dampening: buffer, pH and conductivity

Fountain solution additives: function, pH and conductivity . Check the additive’s role in the fountain solution. A pH measurement alone does not explain dampening conditions.

How to use the printing lexicon?

Start with the definition, then compare the description with your own assignment. Pay attention to the substrate, technology and the moment of occurrence of the defect. Similar symptoms may have different causes.

The terms apply to sheet-fed offset. For other printing technologies, check material and procedure compatibility before applying these recommendations. Select machine settings and additive dosages for a specific product.

Lexicon and guides: from concept to diagnosis

The lexicon explains terminology. Explore the WIT blog for step-by-step diagnostic guides.

• Offset ink is not drying – what to check?
• Problems with water-based varnishing
• Cleaners, auxiliary chemicals and roller care