Coffee Filter Science and Art

Coffee Filter Science and Art

To be honest, I can't remember what inspired this activity! I think it was something to do with pens having permanent ink or water based inks. It doesn't really matter, it was fun and the science behind it is a bonus point!

What you need:

• Some coffee filters
• Pens, try different types to see what happens
• A tray or dish 
• Water

Start off by drawing your design on the coffee filters, leave some space between the colours for the pens where the ink will run. If you are experimenting with different types of pen, use a biro and write the pen type along the sealed edge of the coffee filter.

When you have completed the design. Pour some water into the tray, open the coffee filter and stand it up in the tray, watch as the water gets soaked into the filter...

Remember to ask your child to predict what will happen and why.

This is also a lesson in patience as it takes some time to let the water soak up but slowly the magic starts to happen...

And eventually you end up with some beautiful designs. 

If you split open the coffee filters and leave to dry you can then use them for crafting, they make an interesting addition to the craft paper drawer.

The beauty of this experiment is that it can be done with kids of any age and mixed ages if you have siblings.

The Science:

Permanent markers (think Sharpie) use three main ingredients is specific quantities: colorant, pigment and resin. And although they are called permanent realistically the ink can last from a few months to several years depending on the surface that it's written on.

The colorant in a permanent pen is usually from pigment as it is less likely to bleed through paper and fade less that dyes.

Carriers otherwise known as solvents are what is used to carry the pigment to the paper and must evaporate quickly. These days most pens use alcohol based solvents.

The resin is the binder and this is what causes the pigment to stick the paper and creates a film over it once the carrier evaporates.

The other type of pen are water based markers (like Crayola or Copic) - these re more popular with parents because the ink is easier to remove when you child decides to do a Picasso on the white sofa! (why do people buy white sofas?)

Water based pen use water (duh) or glycerine to suspend the dye in. And because it is water based it's much easier to remove that permanent or alcohol based pens. It also means that in experiments like this the ink will run with the coffee filter in water. To get the same effect with permanent pens try adding a few drops of alcohol (not you gin, that would be a waste) or nail varnish remover may work too.

It would be a good way to extend the experiment, trying different solutions to see what effect it has. Just be sure not to be mixing them together. Start afresh with each new experiment, mixing chemicals together when you don't know what you are doing can lead to some nasty results!

If you try this at home, let me know how it goes!