1. Grade: BIO-44
2.Filtration Speed: Slow
3.Pore sizes: 3μm
4.Disc: 55, 70, 90, 110, 125, 150, 180, 185, 240, 270mm, or OEM
Availability: In Stock
Description of No. 44 Filter Paper:
Hawach No. 44 filter paper has a lower ash content than other filter papers in this series. With diameters: 55mm to 270mm. The efficiency of collecting small particles is slightly lower than that of No. 42, but the flow rate is faster.
Features of Hawach No. 44 Filter Paper:
- Like No. 6 filter paper, the particle retention of No. 44 filter paper is: 3μm
- Flow rate: slow
- A thin version of the No. 42 filter paper that retains smaller particles, but has lower ash per sample and has almost twice the flow rate.
- Ash content <0.007%
- The pH of the paper should be neutral (pH 6.95-7.05). During filtration, it still has a certain wet strength and is resistant to dilute acid. The ash content after burning is extremely low, so the weight of the filter can be accurately obtained during analysis.
- HAWACH has won wide acclaim in laboratories all over the world for its high quality, reliability, and ease of operation. We are constantly looking for simple ideas that will make scientific discovery faster, less expensive, and less time-consuming.
Application:
- Very fine particles are retained.
- Fine particle size filtration, such as barium sulfate, metastannic acid, cuprous oxide, etc.
- No. 44 filter paper is used for quantitative analysis in chemical laboratories. The paper is highly pure, loose, and porous, has a certain filtration speed, and has good retention of barium sulfate precipitation.
Quantitative filter paper can be divided into three grades according to the ash content after burning: A grade < 0.009%, B grade < 0.010%, and C grade < 0.011%. All use refined cotton fibers as raw materials, beating free short fibers, impregnating purified fibers with hydrochloric acid, hand-made and dried, and then treated with mixed acid of hydrofluoric acid and hydrochloric acid to further reduce ash content, and then rinsed and dried.
Selection Guide for Filter Paper

Grade Comparison
Hawach | Whatman | Advantec | Munktell | Ahlstrom | Macherey Nagel |
---|---|---|---|---|---|
BIO-44 | Grade 44 | 6/4A | 391 | 95 | 640de |
Technical Data
Grade | Particle Retention | Product Appearance | Filtration Speed | Ash Content (%) | Basis Weight (g/m2) | Wet Burst (mm H2O) |
---|---|---|---|---|---|---|
BIO-44 | 3μm | Smooth | Slow | <0.007 | 104 | >=200 |
Ordering Information
Item # | Description | NO. | pore size | flow rate | diameter | pack |
BIO-44-055 | Quantitative Filter Paper | Grade 44 | 3μm | Slow | 55mm | 100pcs/pk |
BIO-44-070 | 70mm | |||||
BIO-44-090 | 90mm | |||||
BIO-44-110 | 110mm | |||||
BIO-44-125 | 125mm | |||||
BIO-44-150 | 150mm | |||||
BIO-44-180 | 180mm | |||||
BIO-44-185 | 185mm | |||||
BIO-44-240 | 240mm | |||||
BIO-44-270 | 270mm |
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