Why steam is such a big help

Everyone knows that steam helps a lot with ironing. But only a few know why and how. Read the below and get enlightened about this rather hot topic.

Reshaping fabric

What is ironing, anyway? It is the reshaping of textile fabric from wrinkled to smooth. Simple enough on the surface, quite interesting when you look closely: The heat of the iron loosens the connection between the molecule-chains in the fibres. The pressure of the soleplate then reshapes the fabric, and when it cools down, the connections between the molecule-chains rebuild. So what was a stubborn crease is now smooth and will stay that way (until it is worn and washed again…).

Steam speeds up heating up

Compared to "dry" ironing, using steam speeds up the heating up of the fabric considerably. The reason is that steam transports heat quicker than dry air, so the heat permeates the fabric a lot faster and deeper with steam. This is another way of saying that with steam, you iron faster.

Moisture needed

Steam is not only a highly efficient mode of transport of heat. Steam is water turned to gas and normally contains tiny water droplets - that is what you see when steam comes from your steam iron. So steam is also transporting moisture into the fabric, which is essential for natural materials like cotton.

Not all water boils at 100°C

We all learned at school that 100°C is the temperature at which water boils and turns to steam. This is still true, but only applies to normal atmospheric pressure at sea level. So if you don’t live somewhere on the top of the world the steam coming out of your iron has 100°C. In a steam generator iron, steam is generated under pressure in a separate unit. And the higher the pressure here, the later the water boils and the hotter the steam: steam generated at 5 bar has already 150°C. So the higher pressure makes the steam hotter and lets it permeate the fabric faster and deeper.

That was enough physics for today, thank you for reading this far.

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