My 7-year-old said she’d like some unicorn bunting to decorate her bedroom. We found some instructions online, bought some fabric and got out the sewing machine. But the cotton fabric we had bought was creased and folded. We had to make it all flat and smooth before we could draw on triangle shapes for the flags and cut them out.
So, why does fabric get creased? And why does pressing it with a hot iron make the creases go away? The answer is all to do with chemistry, so let’s find out more…
Fabric and cloth are words we use to describe soft materials that are used to make lots of every day things, like curtains, cushions, bags and clothes.
Think about the clothes you are wearing right now – what are they made of? They may be made from ‘natural fibres’ (which come from things that grow in nature) like cotton, linen or wool. They may be made of ‘synthetic fibres’ (made using chemistry) like acrylic, nylon or polyester. Or they may be made of a mixture of natural and synthetic fibres.
Fibres can be arranged in a regular pattern to make fabrics by weaving, knitting and felting them together. These processes criss-cross the fibres and join them together to make a strong material that can be cut or shaped in useful ways.
Heat and water can change the way in which the fibres join together and criss-cross each other. When you wear clothes, the heat and water from your body can make the fibres in the fabric move about and this can create wrinkles. But heat and water can also be used to push the fibres back to their normal places – which is why we use hot irons to get rid of creases.
But not all fabrics get creases – it depends on what fibres they are made from. As a general rule, natural fibres are more likely to crease than synthetic ones. And some fabrics are made with a special coating that makes them less likely to get creased.
If you’re interested to find out more about cloth materials, here’s a list of fibres and fabrics and how they should be washed and cared for.