Mechanical Greaseproof Paper Grade Selection for Bakeries and Fast Food Packaging
Optimize mechanical greaseproof paper selection by specifying 80-88 SR refining and 15000+ s Gurley porosity to secure non-PFAS grease resistance.
PTS-RH 021-97 Repulpability
Standard Method
Standardized laboratory disintegration procedures defined by the Papiertechnische Stiftung evaluate whether coated paperboards disintegrate completely under standard hydropulping conditions. Adherence to PTS-RH 021-97 repulpability criteria ensures that functional polymer coatings or barrier layers do not produce unusable sticky agglomerates or excessive screen rejects during paper recycling operations. The test simulates industrial pulping by agitating wet paper samples under specified temperature, pH, and consistency parameters.
Laboratory screens then separate usable fiber slush from coarse non-disintegrating fragments.
Defibering Test
Evaluation under the standard protocol requires disintegrating paperboard samples at a consistency of eight percent in water at forty degrees Celsius for twenty minutes. The resulting fiber suspension passes through a lab fractionator fitted with a six-hundred-micrometer slotted screen. Mass calculations measure the dry weight ratio of accepted fibers to total sample input, defining the repulpability yield percentage.
Materials achieving an accept yield above eighty-five percent pass the preliminary repulpability threshold. Visual inspections check whether residual film fragments break down into manageable flakes or remain as large cohesive sheets that clog industrial screening equipment. Water-dispersible polymers and cross-linked starch coatings pass repulpability assessments easily because chemical bonds dissolve in warm water.
Synthetic wax coatings and polyethylene laminates often fail because insoluble sticky residues accumulate on paper machine wires and drying cylinders during commercial recycling operations. Modified barrier formulations balance water resistance during product use against rapid disintegration inside industrial pulpers.
Reject Boundary
Test failures occur when screen reject percentages exceed fifteen percent of initial sample mass or when sticky particles accumulate on testing screens. Coated board samples failing the standard method require mechanical pre-sorting or specialized chemical treatments before entering standard fiber recycling loops. Non-conforming packaging materials risk exclusion from standard paper recycling streams.