Thinnest Whatman™ brand hardened filter paper, highly glazed Grade 50 supports vacuum filtration in Büchner funnels or Hirsch funnels and enables strong retention of very fine crystalline precipitates.
• Thinner filter design (average thickness 115 µm) than most Büchner filter papers
• Acid-treated for high wet-strength and chemical resistance
• Nominal particle retention of 2.7 µm
• Slow flow rates (Herzberg filtration speed 2685 s)
• High purity and low ash content (0.015% ash maximum)
• Compatible with Hirsch or Büchner funnels
We offer three grades of hardened low ash filters. All three are designed for use in Hirsch and Büchner funnel applications and can be customized for an exact fit.
Wet-strengthened filters for vacuum filtration
For many vacuum filtration applications, a thin filter paper with a slow flow rate and excellent wet strength can maintain sample quality and purity. Because Grade 50 thin filter papers are hardened to minimize fiber shredding, they are a good choice for use as carriers in integrated circuits.
Grade 50 thin filter paper is very strong when wet. It will withstand wet handling and precipitate removal by scraping.
Grade 50 is also available in Smear Tab format for wipe testing (e.g., testing of surfaces for radionuclide contamination).