Paperboard Grammage Determination Methods under ISO Standards
Verify paperboard grammage under ISO 536 by conditioning punch specimens at 23 C and 50 percent relative humidity under ISO 187 to protect converting area yield.
Kaolin Clay Stripping
Coating Mechanism
Aqueous pigment suspension displacement allows for the efficient removal of kaolin clay particles from mechanical equipment or residual filter cakes during substrate production. Kaolin clay stripping involves the controlled application of chemical dispersants that neutralize the surface charges holding mineral platelets to metal surfaces or fibre webs. This process prevents the buildup of inorganic deposits that compromise roll uniformity in calender stacks.
Particles liberated during this procedure undergo rapid separation to ensure high purity in secondary fibre recovery.
Process Efficiency
Hydraulic shear stress combines with specific anionic polymers to facilitate the detachment of fine kaolin fragments from industrial screens. Operators monitor the pressure differential across these filtration units to detect when performance drops due to mineral accumulation. Regular cleaning cycles mitigate the risk of abrasive wear on steel components that results from embedded clay crystals.
Efficient reclamation of the pigment depends on the precise balance of water flow rates and chemical concentration levels.
Quality Impact
Surface uniformity in final paper products relies heavily on the removal of stray mineral aggregates during the manufacturing phase. Kaolin clay stripping maintains the integrity of the coating distribution by preventing particle clustering that creates pinholes or streaks on finished sheets. Smooth surfaces emerge when production lines undergo consistent maintenance of these pigment removal protocols.
Poor control over this mechanism leads to unacceptable defects that appear as inconsistent gloss or mottling across a printed surface.