Dispersion & Filter Pressure Test
We use filter pressure to measure how well the pigment disperses in the melt; in thin film and fiber applications, this is the decisive factor.
Undispersed pigment leaves its mark on the filter.
The filter pressure value (FPV) test is carried out using the method defined in DIN EN 13900-5. The masterbatch is diluted with a specified polymer and passed through an extruder and a fine-mesh screen pack; the pressure rise in front of the filter is recorded throughout the test.
Undispersed pigment agglomerates clog the filter and raise the pressure. The result is reported in bar/g: the lower the value, the better the dispersion.
Good dispersion reduces breaks, holes, and gel formation in films and fibers, lowers the frequency of filter changes, and enables more efficient use of pigment for the same color.
What does FPV tell you?
Good dispersion
- Pigment disperses homogeneously in the melt
- Filter life is extended and pressure remains stable
- Break-free production of thin films and fibers
Poor dispersion
- Agglomerates clog the filter
- Pressure rises rapidly and stoppages increase
- Holes, gels, and surface defects
How is the test performed?
- Dilution
Preparation
The masterbatch is diluted with the test polymer at a defined ratio.
- Extrusion
Melt
The blend is melted in the extruder.
- Filtration
Pressure recording
The pressure rise is monitored as the melt passes through the screen pack.
- Report
FPV value
The pressure rise is reported in bar/g, relative to the amount of pigment passed through.
Where dispersion is decisive
Let’s plan tests and samples for your product.
Share your application and target values; our laboratory will recommend the right product and prepare your sample along with its measurement results.
