Inter-Ply Bond Measurement Standards in Recycled Paperboard Production
Inter-ply bond standards mandate TAPPI T 541 or ISO 16260 testing under strict ISO 187 conditioning to prevent converting delamination on recycled paperboard.
Wet-End Cationic Starch
Chemical Additive
Modified polysaccharides carrying a positive charge improve the dry strength and retention of a paper web. The wet-end cationic starch binds to negatively charged wood fibres and mineral fillers during sheet formation. It increases the internal integrity of the substrate by enhancing the network of hydrogen bonds.
Retention Mechanism
Electrostatic attraction pulls the starch molecules toward the fibre surfaces to create a stable bridge between particles. The wet-end cationic starch reduces the amount of fine material lost through the wire during drainage. This process improves the efficiency of the papermaking system and clarifies the white water.
Higher dosages improve the burst strength and the stiffness of the final board. Starch selection depends on the ionic demand of the pulp slurry and the presence of dissolved contaminants. Over-saturation leads to a charge reversal that can destabilize the formation and reduce the effectiveness of the additive.
Strength Enhancement
Final board properties show higher resistance to crushing and bending. The wet-end cationic starch allows for the use of shorter fibres or higher filler loads without losing structural stiffness. Effective application balances the chemical cost against the gain in physical performance for the converter.
Consistent dosing ensures that the paperboard meets the requirements for high-speed packaging lines.