The POROLUX™ 100 series uses the pressure scan method. As this method is fast and typically generates very reproducible results, the POROLUX™ 100 series is regarded as being extremely suited for QC type of work.

A special version of the POROLUX™ 100 is available for materials with large pores such as of textiles and non-wovens.

  • Gas-liquid displacement porometer based on the pressure scan method: the applied  pressure and the resulting gas flow are measured continuously.
  • Very fast and reproducible measurements of  first bubble point, maximum pore size, mean flow pore size, minimum pore size, pore size distribution and gas permeability.
  • Ideal for quality control work.
Max pressure0.15 MPa/ 22 psi
Min pore0.427 µm
Max pore500 µm
Max flow200 l/min
Sample holders25 mm
Pressure sensors2 bar/ 29 psi
Flow sensors10-200 l/min
Calculated FBPYes
Measured FBPNo
Resolution24 bit
Service via internetYes

Nonwovens, fibrous materials and textiles. 



The term non-woven refers to products made by processes that do not include weaving nor knitting (ASTM D1117-80). The fibers in these materials are bonded together by chemical, mechanical, heat or solvent treatment. Non-woven materials are used in applications in different sectors (filtration, automotive, construction, aeronautical, food and medical, amongst other). In 2013 the US nonwoven fabric industry market accounted for $5.4 billion and the demand for nonwovens is forecast to rise 5.7% per year to $7.1 billion in 2016.

As for every material, an in depth characterisation of the structure of non-wovens is essential in order to understand better and improve their performance for a given application.

Capillary Flow Porometry (CFP) measures pore size and pore size distribution of through pores with good accuracy and reproducibility in one individual and fast measurement. The technique is based on the displacement of an inert and nontoxic wetting liquid embedded in the porous network of a material by applying an inert pressurised gas (e.g. nitrogen). The larger pores become empty first and, as the applied pressure increases, so do the smaller ones until all through pores are empty. The gas flow through the sample against the pressure applied is measured. The pressure required to empty pores of a certain diameter is used to calculate the pore size accordingly to the Young–Laplace formula P=4*cos (θ)*γ/D, where (P) is the pressure required to displace the liquid from the pore, θ is the contact angle of the wetting fluid with the material, (γ) the surface tension of the wetting liquid and (D) is the pore diameter.


CFP measurements of melt blown and spun bound materials, were carried out by using a POROLUXTM 100NW porometer from POROMETER nv (right pictured). The POROLUXTM 100NW is specially designed for non-woven characterisation and it is based on the pressure scan method (the increasing pressure and the resulting gas flow are measured continuously during a test). The method is fast and typically generates very reproducible results, which makes the POROLUX™ 100NW very suited for quality control.

The maximum operating pressure of the device is 1.5 bars (22 psi), which permits measring pore sizes between 0.427 µm and 500 µm. The determination of the first bubble point (FBP), or maximum pore size, is based on the test method described in the standard ASTM F 316-03. The FBP is defined “at the pressure required to blow the first continuous bubbles detectable by their rise through a layer of liquid covering the filter”. Since the concept of the first continuous bubbles is subjective. In consequence, a unique universal criteria to calculate the bubble point does not exist.

The POROLUXTM 100NW permits selecting settings accordingly to different criteria traditionally used for FBP calculations. Options include the calculation the FBP at the pressure that corresponds to a flow rate of 30, 50, 100 ml/min, or taking the pressure at which the first measureable flow is detected by the equipment, amongst other. The choice of one method or another is always the ultimate decision of the user.

The criteria selected for calculating the FBP was the pressure at which the first flow was measured. For very porous samples, like non-woven materials, it is recommended choosing “first flow” or “FBP above a certain flow value” because it is not always easy to calculate the FPB at one specific flow value (e.g. 30ml/min). In each measurement, a total of 30 data points were taken in the pressure range from 0- 100 mbar. Three replicates for each sample were measured. The FBP, mean flow pore (MFP) and smallest pore size (SP) of sample “A” (spunbond type material) and “B” (meltblown type material) are given below:

Sample A Average (µm) Std (µm) RSD (%) Sample B Average (µm) Std (µm) RSD (%)
FBP 375.8 2 0.6 FBP 70.5 0.1 0.2
MPF 82.8 6 7.5 MPF 19 1 6
SP 28.3 2 6 SP 7.3 0.3 3

The gas flow against the applied pressure on the dry sample is also carried out (dry curve). The half-dry curve is obtained by dividing the flow values of the dry curve by 2. The MFP is calculated at the pressure where the wet and the half-dry curves meet. It corresponds to the size at which 50 % of the total gas flow can be accounted. The SP corresponds to the pressure where the wet and the dry curves meet. Due to the nature of the calculation of the MFP and the SP these have normally a higher standard deviation than FBP values. As example, the wet, dry and half dry curves for sample “A” are shown below. The rounded shape of the dry curves (dotted lines) is typical of non-woven materials.


The gas flow through the sample is used to calculate the cumulative filter flow distribution against the pore size (percentage of the total flow which corresponds to pores of a certain size and larger) and the differential filter flow (increase in flow rate per unit increase in pore diameter, commonly defined as pore size distribution). The resullts for sample B are shown in the following graphic.


Overall, CFP has proven to be a very useful tool for the non-wovens characterisation industry. If you wish to know more about how CFP can help your non-woven business, contact us at info@porometer.com.

Product codeDescriptionPrice
LIQ100Basic liquid Permeability Extension Kit Porolux 100/500 - 6 liter vessel, external sample holder 25mmPRICE
USHUniversal sample holderPRICE
CONKLOWLow pressure connection kit Porolux 3 m hose and filter/regultor - comes std with P1000, option for P100xPRICE
POREFIL250250 ml. Porefil wetting fluidPRICE
POREFIL10001000 ml. Porefil wetting fluidPRICE
GALPORE250250 ml. Galpore wetting fluidPRICE
SILPORE250250 ml. Silpore wetting fluidPRICE
REF1UMC1,0 µm pore size control sample (100 pc.) + certificate of conformityPRICE
SWUPDATEGeneral Software Update (including - if necessary - PLC + GUI)PRICE
SWLANGLaguage pack 1 extra language (German, Sapanish, Chinese or Russian)PRICE
SWEXTFLOWExtended flow data (CFF) software function (pressure at e.g. 5, 10, 80, 90% flow)PRICE
SWLARGEVOLLarge volumes Software functionPRICE
MANUAL1 Extra printed manual EN/DE/RU/ESPRICE
EX10047Exchange Sample holder Porolux 100 47 mm (instead of SH 25mm)PRICE
EX10013Exchange Sample holder Porolux 100 13 mm (instead of SH 25mm)PRICE
SH13EXTSample Holder complete 13 mm (on external table and extension hose)PRICE
SH25EXTSample Holder complete 25 mm (on external table with extension hose)PRICE
SH47EXTSample Holder complete 47 mm (on external table with extension hose)PRICE
SHUNIV25EXTUniversal sample holder 2-10 mm samples 25 mm (on external table with extension hose)PRICE
SHHFSample Holder complete for hollow fibers (incl 5 sealant rings)PRICE
SHHFBCSBottom connector for hollow fiber sample holder, bore < 3mm (pkg of 10)PRICE
SHHFBCLBottom connector for hollow fiber sample holder, bore > 3mm (pkg of 10)PRICE
SH13TOPUpper Part Sample holder 13 mmPRICE
SH13BOTBottom Part Sample Holder 13 mmPRICE
SH13CAPCap Screw Sample Holder 13 mmPRICE
SH25TOPUpper Part Sample holder 25 mmPRICE
SH25BOTBottom Part Sample Holder 25 mmPRICE
SH25CAPCap Screw Sample Holder 25 mmPRICE
SH47TOPUpper Part Sample holder 13 mmPRICE
SH47BOTBottom Part Sample Holder 13 mmPRICE
SH47CAPCap Screw Sample Holder 13 mmPRICE
SH13METSMetal support set Sample Holder 13 mm, 1 grid / 1 support PRICE
SH25METSMetal support set Sample Holder 25 mm, 1 grid / 1 support PRICE
SH47METSMetal support set Sample Holder 47 mm, 1 grid / 1 support PRICE
SH13METS300mMetal support plate 300µm stainless steel etched diameter 13 mmPRICE
SH25METS300mMetal support plate 300µm stainless steel etched diameter 25 mmPRICE
SH47METS300mMetal support plate 300µm stainless steel etched diameter 47 mmPRICE
SH13ORO-ring Sample Holder 13 mmPRICE
SH25ORO-ring Sample Holder 25 mmPRICE
SH47QRQ-Ring Sample Holder 47 mmPRICE
CLEAN250 ml Stainless steel cleaning fluidPRICE
CPR200Compressor 8 bar - 220 l/min - 55dB(A) PRICE