During the washing, wetting and drying processes, dimensional changes in the form of shrinkage and elongation are observed in the warp and weft directions.
The aim of this experiment was to quantify these changes.
Dimensional change in textile products is commonly seen as weft and/or warp shrinkage, and the shrinkage in the warp direction is usually greater than in the weft direction.
The reason for the fabric shrinkage is the transition of the warp and weft threads under and over each other in the fabric, and when the fabric enters the aqueous environment, the amorphous regions of the fiber swell by absorbing water molecules, thus causing the yarns to get closer to each other and shortening of the fabric in the warp and weft direction.( TS EN ISO 5077 )
Used materials
Scale scale scale
automatic washing machine
Press
Marker pen (not washable)
Detergent
Sample preparation
The fabric sample to be used in the experiment is cut in a square shape of 500 mm x 500 mm parallel to the warp and weft and the edges are sewn with overlock stitches.
As seen in the figure below, three pairs of markings are applied across and across the width of the fabric, with a gap of at least 50 mm from the edges and at least 350 mm between them.
A temperature of plus or minus 4 at 20 degrees Celsius for at least 2 hours until the sample reaches constant weight, and, 65% plus minus It is conditioned under 2 relative humidity standard atmospheric conditions.
Experimental Procedure
After the creases are removed by placing the sample on a flat surface, the lengths between the pairs of points are measured and recorded.
11.8 different detergents are used to prepare the 3 g detergent mixture we will use in this test.
9,09 gr of our ece detergent, which is one of these detergents, is weighed, this amount constitutes 11,8% of the 77 gram detergent solution.
We weigh 2,36 grams of sodium perporate detergent, this amount is 11,8% of the 20 gram detergent solution.
By adding tap water, the solution is heated until the temperature reaches 40 °C.
Then the temperature of the solution is expected to drop to 30 °C.
Then, 3 percent of tetra acetylethylene diamine detergent is added to the solution as bleach, weighing 0,354 grams.
The test sample is washed and dried in an automatic washing machine by adjusting the weight to 2 kg with load-balancing fabrics.
The dried sample is conditioned under atmospheric conditions.
The dried sample is laid without stretching too much for measurement and recorded by measuring between the marked points.
Then, using the formula below, the amount of size change in % is calculated separately in the warp and weft direction.
(Pre-process measurement-Post-process measurement) .100 / pre-process measurement
Then the average size changes are calculated and the amount of shrinkage (results with - sign) and elongation (results with + sign) in size changes are found separately in the warp and weft direction.
After the test, the shrinkage and elongation results in the warp and weft directions are found as percent. Then they are evaluated according to the acceptable tolerances of the enterprises.
