tirsdag den 12. marts 2013

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



søndag den 10. marts 2013

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.  

tirsdag den 26. februar 2013

Children's wear 

The garment we have worked on this time is a jersey tunic in 100% cotton.   The weight of the fabric is 275g per m2.




Fabric
The tunic is made from 100% cotton. Cotton is a natural vegetable fiber from the cotton plant. It has a high next to skin comfort due to its fineness and softness, which is good when you are making children's clothing. The strength of cotton is good, which our bursting test (ISO 13938-1) also show. It broke at 357 kpg, which is really good. High strength is very relevant for children's wear because they are active.  
 
The degree of pilling depends on the quality of the cotton. High quality cotton has long fibers and will therefore pill less. Our test (ISO 12945-1) showed a high degree of pilling.
The result was not a surprise, because even before we did the test, we saw some pilling on the garment.  

The detail with the owl is made of polyester. It didn't say in the care label but after doing a burning test and looking in the microscope we concluded that it must be polyester.    


Composition

The main fabric is a knit called interlock. Interlock is made on two needle beds in which the needles are directly opposed and work alternately. Interlock has a close surface structure and both sides show only face loops and look identical. The fabric is extensible, but not very elastic.



At the bottom of the tunic and the sleeves there is 1x1 rib. Both sides of the fabric show only face loops, the back loops are exposed only when the fabric is stretched in the width direction. 
  

The motive on the tunic is a 4/1 satin.  
 






Dyeing

The fabric have been dyed after it has been knitted. This is a way of making the production price cheaper. What dyestuff you use depends on the final price, direct dyeing is cheaper than many of the others alternatives. Our guess would be that this is the way our tunic have been dyed. The reason why we believe this is the case with our tunic is used and you can clearly see that the color have faded during wash and wear.With the other types of dyestuff you have high fastness properties. Direct dyestuff has a relatively poor fastness to light, washing and perspiration. 

When we tested the color fastness to washing (ISO 105-C06). We did a test both at 40 degrees and 60 degrees, with a washing time of 30 minutes. We didn't see any color transfer to the other test fabric. We believe that it due to the garment being old and having been washed several times. Looking at the care label it states that in the beginning there might be excess color. 
We also did a color fastness to rubbing ( ISO 105-x12). In dry test it didn't rub off any color, in the wet test we saw a minor change on the cotton piece.  

onsdag den 20. februar 2013

Underwear

Ladies underwear

This time we worked with underwear. We choose a string in 95 % polyester and 5 % elastane. 





Fabric

Polyester is a man made fiber and we find it in the synthetic polymers category. Polyester is a very strong material, and when we did the tear test (ISO 13937-2) we were not able to break it, neither in the weft or warp direction. This is of course not only due to the polyester, but also the way it has been woven. Polyester alone is not elastic at all, and that is the reason why elastane have been added in our product. 


The panties also consist of a small part of elastane. Elastane is also a synthetic fiber, it is used to ad elasticity to the garment. It is made only from filament yarns, and is very resistant to domestic laundering, making it suitable for to use in underwear.   

The panties have a small cotton panel as well on the inside of them. We assume that is due to hygienic factors, as the cotton can stand high temperatures during wash and further on that it is easier to clean cotton than polyester. This is of course important when we deal with underwear.



Composition

The panties are put together by different types of fabrics and weaves.The front of the panties is a satin weave 4 over 1. Satin has more even surface than other weaves, because it has fewer interlacings. The shiny surface is also due to the few interlacings. The front and back is very different with this kind of weave, due to the predominance of warp on the front, and opposite on the back of the fabric. The opposite of satin weave is sateen weave, which can be seen on the backside of the fabric.

The detail with the dots is created by doing the weave opposite, so we have the sateen on the front and satin on the back.


To do this weave, you have to use a jacquard weave machine, where you can control each tread, this is necessary, when you have the detail with the dots, where you need to change the weave in a small area.




As with most panties there is a cotton panel in the bottom of the panties. This is a plain weft knit. This can be recognized by the two sides having a different appearance. One side shows only face loops (as seen on the picture), and the other side only back loops.





The back of the panties is called a raschel net, which is very common for lingerie. The lace on the panties is called a raschel lace.





There is an elastic band at the waist of the panties. It is polyester thread with a core of elastane. 







Dyeing
The dye method used to dye this material is called dispersed dyeing. This is the only method that can be used when you work with polyester material. This method makes the result water insoluble. It is applied from dispersions and diffused into the fabric at a high temperature. Materials dyed this way gain good fastness properties, which is a good quality in our case because underwear is something you wash a lot. Further on, you don’t want the colour to transfer to the clothes you are wearing over it either.

That it has a good colour fastness to washing was also confirmed by the test we did (ISO 105 C06). The test showed that it did not transmit colour to any of the other materials in the test. When performing the test we also washed it a higher temperature than the care label suggested, and this did not have an effect on the result either. The reason why we washed it at 60 degrees rather than 40 is because this is what you would normally do with underwear. 

tirsdag den 5. februar 2013

Men's jeans





This time we worked with men's jeans. The jeans we have worked with contains 99 % cotton and 1 % elastane.





The fabric
Cotton is a natural cellulose fiber and it comes from the cotton plant.

As with most jeans the fabric is cotton mixed with a little bit of elastane. Cotton alone is not elastic, so to get higher comfort when wearing jeans, it is often blended with elastane. When working with cotton fabrics you need to be aware that it can shrink up to   10%. Cotton is a very strong fiber, which is a very relevant advantage when using it for jeans. 200kg of raw cotton fibers is enough to produce 325 pairs of jeans. The degree of pilling in cotton depends on the quality. The higher the quality the less pilling and opposite. 

Composition
The fabric used for the jeans is a woven fabric. It is a warp faced 2/1 twill. It can be seen by the dominance of warp yarns on the front side. 


Dyeing 
The warp treads are dyed using a beam dyeing. 
The connection between the cotton and the dyestuff is not very strong, and therefore the color fades over time. To check the color fastness on our jeans, we did a washing test. The result shows that it still stains other fabrics even though it is an old pair of jeans. This emphasizes the theory. Further on, we made a rubbing test both using wet and dry cotton. The dry test stained a little,but nothing compared to the wet test. This was not a surprise as it is very common with jeans. The fabric is made of blue warp threads and white weft threads, this is done because otherwise the jeans would be too blue.   


One square meter of our fabric weighs 415g. In order to make one pair of jeans you need approximately 1,6m of fabric. This would make the total weight of our jeans 664g. 


If you want more information about the process of making cotton you can take a look at the link below:

http://www.youtube.com/watch?v=_KZWe0sYglc

  

tirsdag den 29. januar 2013

Women's blouse



Today's topic was to find a fabric appropriate for a woman's blouse. We have worked with a floral printed, viscose fabric. Further down you can read about it's properties and technical construction of the fabric.


 
The fabric
Viscose is a man-made fiber. It is made from natural polymers like eucalyptus, pine or beech wood. Viscose can be recognized by its characteristic lines, which can be seen on the close up to the right. Viscose fibers are fine and soft and therefore very comfortable to wear.


Composition
The fabric we have worked with is a woven in a plain weave, which is the simplest and tightest type of weave. A plain weave looks the same on the front and back. Further on, it has a strong abrasion and yarn slippery resistance.  





 If we look closer into the yarn composition, we can see that they are twisted in different directions, as you can see in the picture to the right. The technical description can be seen to the left. As shown in the pictures two of the yarns are s-spun and two of them z-spun. This creates a crepé effect called crepé georgette. It is a full crepé because the yarns are twisted in both the weft and warp directions. 


Print
The fabric we have worked with has a floral print. Another property of viscose is that it is easy to print on. Viscose can absorb and therefor you can use dyestuff when printing. It is rotary printed with six colors. This is a fast method to use when printing, further it is more accurate than other printing methods. 




Properties
The fabric would be relevant to use for loose fitting women blouses, due to the fact that it contains no elastane.