These cellulose filters are used in qualitative analytical techniques to determine and identify materials. A standard grade filter paper for fine precipitates.

• Maintains flow rate due to the reduction in filter paper contact with funnel side and the self-supporting shape of the filter itself
• Decreased overall filtration time because of the extra surface area exposed; the normal slow down of filtration speed due to the loading of particulate is postponed
• Savings in time required to quadrant-fold circles to fit conical filter funnels in repetitive or multiple analyses
• Increased total loading capacity as more filter area is available
• The prepleating does not significantly affect any of the technical data, and the same figures may be used for the flat circles

Prepleated qualitative filters give improved flow rate and increased loading capacity compared to equivalent quadrant folded filters.