Purity of the furnish mass percentage usable in papermaking. An assessment of potential impacts on circuit waters or effluents is not part of this method. This criterion is evaluated on the following basis:
Undisturbed sheet formation test
This is assessed on the basis of the following two tests:
- Sheet adhesion test on handsheets made of the obtained stock (both total stock and accept from screening) to detect adhesive impurities (stickies) caused by e.g. Glued side wall and bottom panels, Coating binders, Polymer and other non-paper coatings, laminations and liners, Adhesive labels and tapes and Adhesive contaminants (stickies) in paper and board made of recycled fiber.
- Visual inspection for optical inhomogeneities such as:
• Dirt specks due to ink, coating, metal, paint, glue etc.
• Transparent or white spots or flaws due to stickies, plastic particles, coating particles, etc.
• Through-coloured conspicuous fibers and significant stain of the handsheet due to colorants.