The evaluation scheme deals with the fragmentation of adhesive applications and their removability through a laboratory screening process, said the trade group.
The industry association has produced a scorecard for the removability of adhesives.
“It is applicable to all kinds of printed paper products containing any adhesive applications and serves as an evaluation for potential sticky problems at the paper machine and quality defects in the produced paper or board,” said a statement from the ERPC.
Adhesive removal challenges
The body highlighted the effective removal of adhesives as a real challenge for paper manufacturers using recovered paper – as during the recovery process adhesives disintegrate during pulping into what are known as ‘stickies’. This is an industry terms for all tacky components, explained ERPC.
These are known as macrostickies, microstickies or potential secondary stickies – depending on their size and behavior.
Mechanical screening with slotted screens is the most efficient tool for sticky removal, said the body.
It added: “High removal efficiency can only be achieved if adhesive applications disintegrate into particles of large size. The smaller the particles are, the lower their removal efficiency is. In addition, they can re-agglomerate later in the papermaking process and thus form secondary stickies which lead to major problems in paper production and/or converting processes.”
Their removability depends not only on the composition of the adhesive but also on the type of application, such as the shape of the application and the thickness of the layer. The larger and thicker the layer of a given adhesive, the less disintegration into small particles occurs.
To read a copy of the Scorecard click HERE