Filter paper of very high rate of filtration, wide-pored, soft, spongy structure, extremely low-ash content. Food industry applications: determination of ash contents and PCB determination in foodstuffs. Beverage industry applications: processing (ashing) fruit juice samples for photometric determinations (e.g. phosphate). Environmental analysis: Determination of filterable substances and the residue on ignition (dry weight) for the examination of water, wastewater and sludge (DIN 38 409 part 2).