Whatman 1005-090 Filter Circles, 90mm Dia, Grade 5, 100/pk (PN:1005-090)

Whatman Grade 5 is a qualitative cellulose filter paper designed for laboratory filtration where the goal is to separate and identify substances rather than quantify them. It is especially effective for retaining very fine precipitates in chemical analysis.

This filter has a particle retention of approximately 2.5 µm, making it one of the finest retention grades in the qualitative range. It also has a slow flow rate, which allows for more precise separation of fine particles from liquids.

Grade 5 filter paper is widely used for clarifying cloudy suspensions, water analysis, soil testing, and fine chemical precipitate filtration. Its high retention capability makes it ideal for laboratory and environmental testing workflows.

This product features a 90 mm diameter, cellulose construction, ~200 µm thickness, and is supplied in packs of 100 circles. It also has low ash content (≤0.06%), supporting cleaner analytical results.

Grade 5 is preferred when maximum fine particle retention is more important than speed. While it filters more slowly than coarser grades, it provides superior clarity and accuracy, making it ideal for demanding laboratory applications.