Topics covered: mechanics of doctoring, scumming and hazing, physics of ink transfer and color, transparency, and standardisation under modern constraints · March, June, September and November 2026 · Free for GRA members · Register now

Special Webinars 2026

Special Webinar – Mar

How does changing settings affect doctoring?

Load and angle have considerable impact on the efficiency of doctoring. Numerical simulations and experimental trials have been used to understand how changing settings impact common designs of doctor blades. The changing tip geometry with wear will also affect the hydrodynamic lubrication under the tip. These previous scientific studies are related to practical application on the press.

General Information

Date
2 March 2026 at 10:00 (CET) on Teams

Participation fees
GRA members: free of charge
Non-members: not available for non-members

Special Webinar – Jun

Scumming and Hazing II

Following on from the webinar on 2nd March, this webinar takes an in depth look at issues and science behind scumming and hazing. It reviews past experimental data including the effect of finishing on the surface of the copper and the chrome. This is related to the propensity to scum and the interaction with the doctor blade settings and the ink rheology.

General Information

Date
8 June 2026 at 10:00 (CET) on Teams

Participation fees
GRA members: free of charge
Non-members: not available for non-members

Special Webinar – Sep

What causes the ink to come out of the cells?

Are there ants based on the gravure roller which tell the ink where to go, or could it be due to the fluid dynamics? The ink is subject to a range of different forces to cause it to flow out of the cell and onto the substrate. These include shear as it moves around the cell, cohesive forces as it is pulled out of the cell, and finally extension to breaking point as the roller and the substrate separate. These are all affected by the rheological properties of the ink. The focus will be printing onto film, as the flow of the ink into porous substrates such as paper adds a whole new level of complexity and will be a future topic.

General Information

Date
21 September 2026 at 10:00 (CET) on Teams

Participation fees
GRA members: free of charge
Non-members: not available for non-members

Special Webinar – Nov

Is your ink the right color and transparency?

As customers become more demanding, it is increasingly important to ensure your raw materials are consistent. Ink colourimetric characterisation for CMYK is already established, though there is a need to further refine the tolerances. Special colors fell outside the scope of this earlier work, and there is a need to have appropriate techniques for the various expanded gamut. The presentation will look at the revisions being made to international standards and how these might be applied in practice. As well as colour, other aspects are transparency, as this interacts with print sequence and the relationship with the rheology of the ink. The latter is particularly important as we move to new, more environmentally friendly pigments and resins.