Cellulose Filter Papers
Whatman filter papers are world-renowned as the standard for laboratory filtration and are associated with quality, reliability, and customer service. The familiar Whatman Blue Box is the laboratory benchmark for filtration. Papermaking skills have been developed to the highest level, with the expertize and technology to manufacture innovative multilayer materials.
Whatman offers an extensive line of filter papers. The innovative features of these filters make them the optimum choice for many filtering techniques. Whatman maintains a guaranteed quality, reproducibility, and uniformity for all its filters by using only the highest-quality raw materials. The filters are tested for basic weight, thickness, air flow, and mechanical strength. In addition, special parameters such as particle retention, wicking rate, filtration performance, and surface characteristics can be measured as needed.
Whatman Grade 42 Ashless Quantitative Filter Papers - 2.5μm
A world standard for critical gravimetric analysis with the finest particle retention of all Whatman cellulose filter papers. Typical analytical precipitates include barium sulfate, metastannic acid, and finely precipitated calcium carbonate.
Whatman Grade 43 Ashless Quantitative Filter Papers - 16μm
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.
Whatman Grade 44 Ashless Quantitative Filter Papers - 3μm
Thin version of Grade 42 retaining very fine particles but with lower ash weight per sample and almost twice the flow rate of Grade 42. 0.007% ash maximum.
Whatman Grade 5 Qualitative Filter Papers - 2.5μm
The maximum degree of fine particle filtration in the qualitative range. Capable of retaining the fine precipitates encountered in chemical analysis. Slow flow rate. Excellent clarifying filter for cloudy suspensions and for water and soil analysis.
Whatman Grade 50 Hardened Low Ash Quantitative Filter Papers - 2.7μm
Retention of very fine crystalline precipitates. The thinnest of all Whatman filter papers. Slow flow rate. Hardened and highly glazed surface. This finish also keeps the paper free from loose surface fibers.
Whatman Grade 52 Hardened Low Ash Quantitative Filter Papers - 7μm
The general purpose hardened filter paper with medium retention and flow rate. Very hard surface; 0.015% ash maximum.
Whatman Grade 54 Hardened Low Ash Quantitative Filter Papers - 22μm
Very fast filtration for use with coarse and gelatinous precipitates. High wet strength makes this grade very suitable for vacuum assisted fast filtration of ‘difficult’ coarse or gelatinous precipitates. 0.015% ash maximum.
Whatman Grade 540 Hardened Ashless Quantitative Filter Papers - 8μm
The general purpose hardened ashless filter paper with medium retention and flow rate. Extremely pure and strong with a hard surface. High chemical resistance to strong acid and alkali.