We conform to certain standards when testing our products and those of our customers. These standards are shown here.

1. Test room conditions
The standard conditions are:

  • Temperature: 18 ± 2°C
  • Relative humidity: 65 ± 2°C

All tests must be carried out in conditioned state.

2. Breaking strength and elongation at break
The breaking strength is the force that leads to the rupture of the thread or yarn. The corresponding value is Newton (N). The elongation at break is the increase in length produced by stretching a test specimen to the breaking point expressed as a percentage of the initial length. The test is carried out on a dynamometer with a constant increase in elongation according to the following conditions:

  • Length between clamps = 500mm
  • Test velocity; if elongation at break:
      < 0.08mm = 50mm/minute
      0.08 - 0.50mm = 500mm/minute
      > 0.50mm = 1000mm/minute
  • Pre-tension = 2cN/tex

3. Tenacity (yarn count tenacity)
This is calculated from the breaking strength and yarn count and is expressed in centinewton per tex (cN/tex):

Tenacity (cN/tex)  =       breaking strength (N)    
Yarn count (dtex) x 0.001

4. Load at specified elongation (LASE)
This is the load resulting from a defined extension (usually at 2% and 5%).

5. Hot air shrinkage
This is the shrinkage in length in percent caused by treatment with hot air. We distinguish between free shrinkage and shrinkage under pre-tension.

Free shrinkage (corresponds to the shrinkage curve)

This value defines the change of length after the influence of heat.

Method: After the measurement of length (L1) under 2 cN/tex pre-tension at the defined temperature (between 100-200°C) during 15 minutes. After a cooling time of 1 hour under standard atmospheric conditions the shrunken length (L2) will be determined again with 2 cN/tex pre-tension. The residual shrinkage is then calculated according to the following formula:

(L1 – L2) x 100

Shrinkage under pre-tension
This value defines the change of length during the influence of heat.
Method: The sample is introduced into the heating channel with a pre-tension of 0.1 cN/tex at 160°C. The shrinkage will be read in percent directly from a scale.

6. Boiling water shrinkage
This is the shrinkage in length in percent which is caused by boiling water. It is calculated as follows:

Diameters up to 0.30mm

On a standard reel skeins of 1m circumference and 5000 dtex approx. are prepared and measured at a pre-tension of 2 cN/tex lengthwise (L1).

Diameters from 0.31mm

A single end of 1m length is measured a at pre-tension of 2 cN/tex.

The skeins are the single yarn resp. are then treated without tension during 30 minutes in boiling water (98°C), dried and conditioned at standard conditions.

The shrinked length (L2) is determined again with 2 cN/tex pretension.

The boiling water shrinkage in percent is calculated according to the following formula:

(L1 – L2) x 100

7. Yarn count
The yarn count decitex (dtex) corresponds to the yarn weight in grams of 10,000m length. In order to determine the yarn count, a skein is wound on a standard reel under a pre-tension of 2 cN/tex. The determined yarn length is then weighed on an analytical scale.

PA PET Skein length
Diameter    <15/100
11/100 - 16/100
5 x 1m

8. Abrasion Testing
Very important to many of our customers is our ability to test the abrasion resistance of our own and customers products. We usually use a diameter of 0.28mm for comparison.