Sartorius quantitative filter paper discs, grade 393 (equivalent to grade 42)

Sartorius quantitative filter paper discs of grade 393 are designed for analytical tasks requiring high precision and retention of extremely fine precipitates. Made from 100% acid-washed cotton linters with an α-cellulose content exceeding 98%, these papers are ash-free (≤0.01% according to DIN 54370) and exhibit excellent chemical purity. Their very fine-pore, very dense structure ensures very slow filtration, making them ideal for critical analyses in laboratories, especially where minimal particle interference and high retention accuracy are needed. Grade 393 is a direct equivalent of Whatman grade 42 and is widely used when ultra-fine crystalline precipitates must be retained.

The filter paper has a basis weight of 100 g/m², thickness of 0.18 mm, and offers a filtration speed of 300 seconds for 10 mL of distilled water at 20°C. Its particle retention capacity ranges from 1–2 µm, making it highly effective for very fine crystalline materials.

Ordering information — item codes by diameter (Filter discs, 100 pieces)