Detergents are supposed to remove stains, and you can find out how well by carrying out washing tests. But each stain can only be washed once, right? So how can I make comparisons between detergents and find out which conditions are best for removing the stains? The answer is, before I wash, I first need to make multiple pieces of fabric dirty. The experts call this "staining". In this experiment, we want to show you the principle of how the professionals do it, so we won't use real detergent. Instead, you can use a little dishwashing detergent.
Laundry lab
You will need
- Equal-sized pieces of cotton fabric (for example, from old white undershirts)
- Something to make a stain – for example, beet juice, cocoa and lipstick
- Cold and warm water
- Container for washing
- Dishwashing detergent
- Stopwatch
- Spoon for stirring
Let’s get started!
1. Staining
Cut out four equally sized square pieces of fabric from an old white T-shirt. Stain each piece of fabric in the same way, making sure that each type of stain is applied to the piece of fabric a total of three times and that the stains do not touch each other. The stains should all be the same size.
2. Test no.1 – cold water
Take the first piece of cloth and put it in a large glass or washing bowl. Add 0.7 l of cold tap water and stir for 5 minutes. Then take out the piece of cloth and wring it out well.
3. Test no. 2 – cold water, long wash
Take the second piece of cloth and place it in a large glass or wash bowl. Add 0.7 l of cold tap water and stir for 10 minutes. Then take out the piece of cloth and wring it out well.
4. Test no. 3 – cold water and dishwashing detergent
Take the third piece of cloth and place it in a large glass or wash bowl. Add 0.7 l of cold tap water and half a teaspoon of dishwashing detergent and stir for 5 minutes. Then take out the piece of cloth and wring it out well.
5. Test no. 4 – warm water
Take the fourth piece of cloth and place it in a large glass or wash bowl. Add 0.7 l of cold tap water and stir for 5 minutes. Then take out the piece of cloth and wring it out well.
6. Evaluation
Place all four pieces of fabric next to each other and try to answer the following questions:
Do all the stains wash out equally well (or poorly)?
Which test produced the best result?
Which test produced the worst result?
How could the experiments be improved?
