These qualitative filter papers are essentially used for analytical and routine analyses, when no gravimetric analyses are required. They are wet strengthened and can be used for pressure and vacuum filtration.
They are available in different formats as in rolls, sheets, discs and folded filters.
Specifications of the different paper grades
|
| Grade |
Precipitation |
Properties |
Basis Weight |
Particle retention (g/m²) |
Filtration rate (µm) |
| 1288 |
Coarse crystalline |
Wide-pored, soft, spongy structure, wet strength, fast rate of filtration |
84 |
12-15 |
10 |
| 1288 N |
Coarse crystalline |
Wide-pored, soft, spongy structure, wet strength, fast rate of filtration extra wet strengthened |
84 |
12-15 |
10 |
| 1289 |
Medium-fine crystalline |
Medium-wide-pored, wet strength, medium rate of filtration |
84 |
8-12 |
20 |
| 1292 |
Fine crystalline |
Medium density, wet strength, moderately, fast rate of filtration |
84 |
5-8 |
50 |
| 1290 |
Fine crystalline |
Narrow-pored, dense, wet strength, slow rate of filtration |
84 |
3-5 |
100 |
| 1291 |
Very fine crystalline |
Fine-pored, highly dense, wet strength, very slow rate of filtration |
84 |
2-3 |
180 |
| 293 |
Very fine crystalline |
Fine-pored, highly dense, very slow rate of filtration |
80 |
1-2 |
300 |
|
Filtration rate
|
The time required to filter 10 ml of distilled water at 20°C through a free-hanging, fully-wetted disc filter with a diameter of 110 mm folded in quarters. Expressed in seconds (per mm).
|
