Virgin and Recycled Fiber Ratio Auditing in Packaging Board Production
Paperboard fiber ratio auditing requires pairing ISO 9184 Graff C microscopic stain counts with EN 16995 chemical marker testing and mass-balance credit ledgers
Micro Stickies Count
Contaminant Density
Analytical testing of recycled pulp streams measures the concentration of dispersed, sub-sieve sticky particles that pass through standard laboratory screen openings. The micro stickies count is the quantitative tally of these colloidal adhesives, resins, and synthetic binders that remain suspended in the pulp slurry. This measurement helps mill operators assess the risk of deposit formation on the paper machine’s forming fabrics and dryer screens.
The count is bounded by the particle size, typically targeting contaminants smaller than one hundred micrometers.
Measurement Protocol
Monitoring these tiny particles requires specialized separation techniques such as flow cytometry or laboratory-scale flotation cells. In the micro stickies count procedure, the pulp slurry is filtered or centrifuged to isolate the organic particles, which are then dyed with fluorescent stains to make them visible under automated optical sensors. This system counts and sizes the particles, providing the mill with data to optimize the dosage of talc or fixing agents.
These additives prevent the stickies from agglomerating into larger deposits that could ruin the paper web.
Machine Performance
High counts of micro stickies lead to frequent paper machine shutdowns for wash-downs and cause pinholes in the paperboard. These defects reduce the strength of the board and can cause breaks on high-speed printing presses. Maintaining a low count is essential for producing high-quality recycled board for packaging.