Functional wear

We have worked with a jacket used for workwear as a welder. It is made from 100% cotton.

Fabric
The jacket is made from 100% cotton, which is a very strong fiber, and therefore relevant for workwear. Further cotton develops scarcely any electrostatic charge, which is also good, because that could create dangerous situations in the work environment.
 
More information on cotton can be found in our other posts.  


Cotton usually burns quickly, which is   not a good quality when working with open flames. We tried to burn a piece of the fabric and it was difficult to ignite and it burned slowly. This indicates that the fabric has been treated with a flame retardant finish. Some trademark examples of such finishing could Proban or Pyrovatex. 
In the producer's catalog they have a section about Proban. They use Proban to prevent spreading of flames if the garment by accident should get into contact with a flame. Further, it protects the user against small  splashes of melted metal which occurs when welding.    



We looked at the producers homepage to get more information about the garments. They work closely with FORCE Technology which is a EU testing agency. They test the finished products against the standards requirements. We found that there is an ISO standard only regarding protective clothing for use in welding, called ISO 1161-1.



On the producers homepage they claim that the print is strong enough to withstand normal washing procedures, but the garment clearly shows that this is not the case.

 Construction 

The fabric is constructed of a 3/1 warp faced twill, where the interlacing causes diagonal lines to appear in the fabric.





Testing
Tear strength:
We did a tear test (ISO 13937-2) to see how much the fabric could stand before it broke. The results show that in the weft direction it breaks at 18.74 N and in the warp direction at 32.66 N. The reason why the warp is stronger is that there are more treads in that direction. When we counted them we found  19 threads in the weft and 27 in the warp direction.  

Abrasion test and Specimen breakdown (ISO 12947-2):
We decided to check the abrasion on the garment. We used a 12 kPa pressure, due to it being workwear. The threads broke somewhere between 10.000 and 15.000 turns, however only 2 out of 4 samples broke. We believe that the result we got was satisfying. With work wear like this it is important that it has a high abrasion level.

Dyeing
We believe that the dyestuff used is called reactive. This gives very good fastness properties which is necessary for a garment like this which is washed several times and can stand high temperatures, which gives higher requirements to the dyestuff.  

Usually we would do a color fastness to washing test (ISO 105-C06). Previously when we have worked with worn clothing there has not been any interesting results because it has been washed several times. We believe that it would be the same this time, so we decided to focus on the other tests. 

Sources:
http://www.fe.dk/Default.aspx?ID=706

Jacket

 

For our own choice, we decided to work with a wool/acrylic fabric, relevant to use for jackets. 









Fabric
The fabric is a wool and acrylic blend - 86% acrylic and 14% wool.
Before we knew the percentage of each material, we did a test where we used caliumhydroxid to seperate the wool from the acrylic, to see how big a percent each fiber were of the garment. The test showed that it consisted of 78% acrylic and 22 % wool. The difference from the actual percentage, could be due to the small sample we used for the test. A larger sample could give a more accurate result. 

 One thing that suprised us was when we did a burning test. When burning the threads, wool smells like burned hair, and acrylic like plastic. When we did the test we found that it the smell was like burned hair, which was surprising, due to acrylic being the largest part of the garment.  

 

 Wool is a natural protein fiber. Wool has a very good thermal insulation, which is a good property when making jackets. Further wool is elastic and extensible, which makes it comfortable to wear without using elastane. 
Wool is blended with synthetic fibers like acrylic in this case, to improve the durability and easycare, it can also be to cheapen the price, because acrylic is a very cheap fiber. 
Acrylic is a synthetic polymer. Acrylic has a wool-like handle, which makes it ideal for blending with wool. Acrylic yarns are often voluminous and very soft and warm, which clearly can be seen in our fabric. 




 


To test if the easycare when washing, had been improved after blending, we did our own washing test. We tried to wash a sample of the fabric in 60 degrees water for 30 min. Usually wool should be washed at 30 degrees. After the wash the fabric had shrinked, and many small fibers could be seen on the surface. We concluded that even though there were only 14% wool in the fabric, it still has an influence when washing.

We did a tear test (ISO 13937-2), to test the strenght of the fabric. The sample ripped at 59,21 N, which we believe is good. 

Construction 
The weave is a plain weave, this is very clear due to the thick threads used. 
The fabric is woven very loose, which could also explain the degree of pilling we saw, when doing the martindale pilling test (ISO 12945-2):
125 turns - there is some small gatherings of fibers, and some pilling. 
500 turns - there is a lot of pilling and the threads filtered together.
2000 turns  - the threads were even more filtered together, and it was hard to get the two fabrics away from eachother. 

We looked in a microscope to see how many wool fibers we could see, and it was very clear that mostly it consisted of acrylic - we only found few wool fibers. 

Dyeing  
We believe that the fibers have been colored seperately when they were still at the fiber stage. 
When dying wool the most common dyestuff is acid, which is applied from an acidic dyebath. Chrome, which is another dyestuff for wool is only used when working with very special colors. 
The dyestuff used for acrylic is a basic dyestuff. This is the only possibility when working with acrylic.