Abstract: Archival quality aperture cards manufactured from stock formulation including:1. between 40 and 60% southern softwood kraft pulp;2. between 60 and 40% northern mixed hardwood pulp;3. between 1.5 and 2.5% on total pulp, calcium carbonate for alkaline reserve;4. between 0.05 and 1.0% on total pulp, alkyl ketene dimer as an internal sizing agent;5. between 0.2 and 1.0% on total pulp, cationic potato starch for internal bonding improvements;6. between 0.5 and 2.0% on total pulp, cationic potato starch as a surface sizing agent;7. between 0.5 and 2.5% solids added to the surface sizing agent, alkyl ketene dimer as a slip agent; and8. between 0.01 and 0.3% dyed rayon granitizing fibers.

Abstract: There is provided a composite sheet material for fabrication of storage envelopes for magnetic recording media, e.g., floppy diskettes. The material has a low debris count, and a fast rate of static decay as well as high stiffness and strength.