Qualitative Filter Papers-Grade 6: 3μm

Grade 50: 2.7 μm*
Retention of very fine crystalline precipitates.

The thinnest of all Whatman filter papers with a slow flow rate, these filters have a hardened and highly glazed surface, which also keeps the paper free from loose surface fibers.

Highly suitable for
qualitative or quantitative filtrations requiring vacuum assistance on Büchner
or 3-piece filter funnels.

Very strong when wet and will withstand wet handling and
precipitate removal by scraping.

In the electronics industry, the virtual absence of
fiber shedding is utilized in carriers for integrated circuits.

This grade is also available in Smear Tab format for wipe testing (e.g. testing of
surfaces for radionuclide contamination).

Grade 43: 16 μm*
Intermediate in retention between Grades 40 and 41, and twice as fast as Grade 40.

Typical applications include foodstuffs analysis, soil analysis, particle collection in
air pollution monitoring for subsequent analysis by XRF techniques, and inorganic
analysis in the construction, mining, and steel industries.