Ahlstrom 642 Standard Qualitative Filter Papers

Item No.:
12.5 cm
Unit of Measure:
Pack of 100
Your Cost:
This item is not currently stocked. Allow 1-2 weeks. Please call us at 800-328-8378 if you'd like us to keep stock in the future In Stock Add to Cart

Ahlstrom 642 Standard Qualitative Filter Papers have finer particle retention than 601 but with slightly lower filtration speed, and higher absorption. They are used in general laboratory applications to retain particles above 2µm in size. Grade 642 is also found in agricultural and environmental laboratories for plant growth trials, soil testing, and air analysis for monitoring specific contaminants and the filtration of organic and sulfide precipitates.

Standard qualitative filter papers are suitable for quadrant folded or gravity flow applications. These grades contain a high level of alpha-cellulose that provides high purity but will weaken when wet. The inherent strength of standard (untreated) grades does not pose a problem when they are used in routine quadrant folded applications. Not recommended for use in vacuum work or when went handling is required.

Key Features

  • Retention: 2.0µm
  • Filtration Speed: 229 sec/100mls (Herzberg), 30 mls/min (Rapidity)
  • Medium Loading Capacity
  • Equivalent to Grade 2