Archival Protocol
Representative specimens of manufactured materials are systematically archived at the production site to provide a verifiable historical record of each delivered run. When disputes arise over board stiffness or surface coating consistency, batch retention samples offer a reference point for laboratory re-testing. These physical specimens are typically held for at least one year or until the produced stock has been fully converted and printed.
The collection covers every distinct reel or pallet group produced during a continuous mill run. This procedure ensures that any quality claim can be investigated using specimens that have not been exposed to the variable environmental conditions of the printing floor or the converting line.
Storage Condition
Environmental control prevents the degradation of cellulose fibres and surface treatments during the archiving period. Mill laboratories maintain batch retention samples in temperature-controlled, dark cabinets to prevent yellowing of the outer layers or changes in moisture content. Moisture variation can alter the stiffness and fold endurance of the board, rendering older specimens unrepresentative if they are exposed to ambient humidity.
Verification Method
Verification of the physical stock involves side-by-side comparison under standardized lighting. If a customer reports a failure in the gluing or creasing of a board shipment, technicians extract the corresponding batch retention samples to perform comparative tensile tests and surface energy measurements. This analytical step demonstrates whether the board left the mill with the specified properties or suffered damage during subsequent transit and converting.
