Characteristics and Selecting Factors of Filter Paper


Usually, there are four major properties for customers to choose their suitable filter papers. The chart has been summarized below.

CharacteristicRelated Principle
HardnessThe filter paper can become wet in the filtering procession, so some experimental steps with a long time should consider the tougher filter paper after its wetness.
Filtration efficiencyThe density and size of the pore on the filter paper all impact the filtration efficiency that shows in fast filtering speed and high resolving ability.
CapacitySolid particles can be accumulated during filtration and block small holes on the paper, so the denser the pore is, the higher the capacity would be.
ApplicabilitySome filter papers are manufactured according to especially given steps, such as the use of nitrogen-free filter paper in the determination of blood nitrogen content of pharmaceutical products.

Filter Paper Selection

The selection of suitable filter paper must be determined by the following three factors.

Firstly, the hardness of the filter paper will be wet when it is filtered. Therefore, in the long process of filtration, the more tough filter paper should be chosen.

Secondly, it’s filtration efficiency, which is mainly determined by the compactness of the pore on the filter paper and the size of the pore.

Finally, capacity is mainly determined by the density of the pore, the denser the pore, the higher its capacity. It can be summarized as follows:

1. The effective area is large, that is, the filter paper has a large area of use, the dust capacity is large, the resistance is small, the service life is long, of course, the cost will increase accordingly.
2. The finer the fiber diameter, the better the interception effect and the higher the filtration efficiency.
3. The content of the binder in filter material is high, the tensile strength of paper is high, the filtration efficiency is high, the wool dropping phenomenon is small, the background dust of filter material is small, the resistance is good, but the resistance increases correspondingly.