Automated testing is coming! LISTER AUTO liquid strike-through time

 LISTER AUTO combines five single measurement positions in a rotating unit for automatic and successive measurements of the liquid strike-through time, i.e. the time it takes for a known volume of test liquid (simulated urine) applied to the surface of a specimen of nonwoven coverstock, which is in contact with an underlaying standard absorbent pad, to pass through the nonwoven material.

System for automatic liquid strike-through time test of multiple samples of nonwoven coverstock or topsheet according to EDANA/INDA WSP 70.3 (former ERT 150) and WSP 70.7 (former ERT 153).

Multi-sample

High-volume testing is made easy by means of a rotating plate, which presents up to five single samples successively to the integrated LISTER unit.

Fully automatic

After the samples have been positioned, LISTER AUTO performs the liquid strike-through measurement fully automatically and the operator is free to carry out other tasks.

No manual test liquid handling

For each single test, the needed amount of test liquid is discharged automatically. This means controlled liquid feed and less subjective influence by the operator.

Repeated test made easy

In cases where the repeated liquid strike-through test is part of the routine, LISTER AUTO guarantees for a subjective measurement procedure together with time savings:

The integrated timer controls the time span between the specified single measurements and eliminates any subjective impact due to manual time measurement. Moreover, the fully automatic procedure yields time for other important chores.

Efficient and cost-saving

The fully automatic liquid dosing- and measurement procedure means that less time is spent for the liquid strike-through measurement, the need for personnel resources is reduced and cost savings can be achieved.

Objective results

The high automation degree ensures for objective, accurate and reproducible results without any human impact on the test results.

Standard setting

For more than 40 years, Lenzing Instruments have set the standards when it comes to determination of liquid strike-through properties of nonwovens.Lenzing Instruments is partner of EDANA for the liquid strike-through measurement.

Supplier of filter paper

The needed standardized filter (blotter) paper can be acquired from Lenzing Instruments

Test method

A known volume of liquid (e.g. synthetic urine) is automatically and at constant rate discharged through the centre hole of the LISTER electrode plate onto the sample of nonwoven coverstock. A timer is activated as soon as the electrically conductive liquid passes the electrodes. The nonwoven sample is placed onto a set of standardized filter papers, which serves as the absorbent core. After the liquid has penetrated into the absorbent pad, the electrical circuit is interrupted, the timer is stopped and the liquid strike-through time is displayed. The turntable moves to present the next nonwoven sample to the LISTER measurement unit. Standardized according to INDA/EDANA WSP 70.3 and WSP 70.7.

Technical specifications

Number of samples for automatic determination: 5

Resolution: 0.01 s

Accuracy: Better than EDANA/INDA testing standards

Repeatability:

The instrument complies with the international standard WSP 70.3 (equivalent to EDANA ERT 150.05 (02) and ISO reference 9073 - 8: 1998) and the international standard WSP 70.7 (equivalent to EDANA ERT 153.0 (02) and ISO reference 9073 - 13: 2006) before completing the liquid After the penetration time test, the same sample can be used to directly test the rewetness of the non-woven fabric.