Cellulose filter papers are used for general laboratory filtration, analytical and technical applications. They are standard documents in many specifications and processes. The wide variety of properties makes them widely used in various fields.
Cellulose filter papers are the most commonly used filters in laboratory, technical and industrial filtration. Generally they can be divided into qualitative filter papers and quantitative ashless filter papers.
Qualitative filter papers are standard papers for most applications and are used for general laboratory filtration, e.g. for the determination of dry substances or the clarification of liquids. Qualitative filter papers are classified as round and pre-folded filter papers.
Quantitative ashless filter paper
Quantitative filter paper, also known as ashless filter paper, is acid washed and has a very low ash content (%3C 0.01 %). It is used for ignition residue testing or contamination-free filtration.
Filter paper has different surface structures.
Smooth surface - standard
Surface pleats - higher stability and faster filtration speeds
Embossed surface - larger filtration area
Wide range of specifications and sizes
MACHEREY-NAGEL filter papers made of cellulose are available in different sizes and dimensions. If you don't find the right size for you, we offer a customised service on request.
Technical parameters of filter paper
Ash content/residue on combustion
Determination of the ash content according to DIN 54370: 10 g of filter paper is weighed after ignition in a platinum crucible at 800 °C and the result is expressed as % of the original paper weight.
basis weight
The basis weight was determined for a 10 x 10 cm sample. The unit is g/m².
filtration speed
In order to determine the filtration rate according to DIN 53137, the duration of 10 mL of distilled water flowing through a 12.5 cm diameter quarter-folded, free-hanging filter ring was measured. The results were expressed in seconds.
thicknesses
The thickness of the paper is measured with a touch pressure device. Especially with soft and wrinkled paper, it is important that the touch pressure is not too high. Otherwise, the paper is compressed and an incorrectly low thickness is obtained.
particle retention
Particle retention is the efficiency with which filter paper retains certain precipitates. It is characterised by the permeability of the paper to precipitates of iron(III) hydroxide, lead sulphate, calcium oxalate and barium sulphate.
