This month we will look at the way our clothes are put together. Clothing serves several different purposes; it keeps us warm, it protects our skin, but probably most important requirement of clothing is that it has to look good. There are many different types of fabric that are used in clothes, and they all look different under the microscope. Here we will look at a few different examples. We will leave you to look at your own clothes to see what they look like.
Here are some Denim jeans which are rather faded. The traditional blue color can still be seen, although the material looks rather pale. The orange stitching can also be seen. In the middle image the woven nature of the fabric can easily be seen as the threads run over and under each other. The blue color of the denim comes from the colored outer fibers of the thread. Where these have been worn away the white fibers which are in the center of the thread become visible - giving the pale faded appearance to these jeans. The third image shows the orange stitching disappearing and reappearing through a needle hole in the jeans.
Polar Fleece is a material that was developed to keep us warm, without being too heavy. To do this it has to be able to trap large amounts of air (which is a good insulator) in a way that prevents it from blowing around inside the material. Looking at these images we can see that this is done by having lots of randomly looped fibers. This creates a loose maze that sucessfully traps the air, and keeps us warm. Because the material is so loose, it is difficult to get nice, crips printing on the material - particularly since all the fibers run in all different directions, so the pattern on the material tends to look a little "fuzzy".
Knitted cotton fabric, in this case a pair of underpants, has a slightly different requirement than the polar fleece does. In this case we would like the material to have a particular shape, and be soft against our skin, and yet still stretch a little bit so that we can put the clothes on. It is the knitting that enables all of this to happen. Rows and rows of interlocking loops make up the fabric. When we stretch the material the individual loops all distort to accommodate the stretch, without trying to break the yarn.
The knitted cotton underpants were just plain white. This poly-cotton fabric has been printed with pretty, colored design. We can tell that the pattern was printed onto the cloth after it was made by looking at the magnified image on the right. The cloth is formed by threads running up-and-down woven between other threads which run left-to-right. The pattern is then painted on the finished cloth so that both sets of thread get colored with the right color.
It is not always possible to print the pattern onto the finished fabric like that. Sometimes, as in the case of this silk fabric, the colors do not take very well. In this case the individual fibers have to be dyed a particular color, and the final pattern is then made up by combining threads of a different color. In the magnified image on the right the blue threads are seen to be running left-to-right, whereas the other colors are woven through them up-and-down.
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Last Update: 3/21/98