Optimizing Multi-Ply Layering for Enhanced Post-Consumer Containerboard Performance
Multi-ply layering of post-consumer containerboard optimizes flexural stiffness and crush resistance by concentrating long fibers in outer faces.
Wastepaper Grade OCC 11
Raw Material
Recovered packaging materials collected from commercial and industrial sources provide the primary fibre source for the manufacture of recycled containerboard. The industrial specification known as wastepaper grade OCC 11 consists of corrugated cardboard sheets and boxes that are collected for recycling. This grade is subject to strict limits on prohibited materials and outthrows to ensure it can be processed back into usable paper pulp.
The boundary of this standard is defined by national paper recycling associations, which set maximum moisture and non-paper contaminant levels.
Processing Requirement
Repulping this recovered material requires high-consistency pulpers that use mechanical action and water to break down the sheets into individual fibres. Because wastepaper grade OCC 11 contains remnants of adhesive tapes and plastic strapping, the stock preparation line must include screens and cleaners to remove these contraries. If these contaminants are not separated, they accumulate on the paper machine wires and cause holes in the newly formed sheet.
Maintaining clean screening loops prevents defects in the finished linerboard.
Fibre Quality
Recycled kraft fibres in this grade retain high levels of their original strength, making them suitable for producing strong testliner and fluting. Every cycle of recycling shortens the fibres, so adding a portion of this grade maintains the tear and compression strength of recycled packaging board.