Why does dry erase marker float in water? If you have seen the online videos showing the experiments done with dry-erase markers, then you have probably been amazed at how it floats on the surface of the water. Why does it seem like the things drawn using dry-erase markers detach and come to life?
Although it may seem like it, there is no magic involved. This can all be explained by science. However, even if you understand how it works, it will not take away from the wonder and bewilderment of the process.
Why Does Dry Erase Marker Float in Water?
To learn why dry-erase marker ink floats, you will need to learn about the components contained in it. And the main components of dry-erase ink are isopropanol (isopropyl alcohol), SD alcohol-40, and resin. These components play a major role in the specific reasons why dry-erase markers float in water
Not that adhesive resin
One reason is that the resin used in dry-erase markers is not nearly as adhesive compared to the ones used in permanent markers. The resin is just sticky enough to hold the pigment.
However, it is also not enough to stick onto non-porous surfaces. This is the reason why dry-erase markers would float while detached from the writing surface when submerged in water.
Isopropyl alcohol is less dense compared to water
Another reason why the dry-erase marker behaves the way it does is that the isopropyl alcohol is less dense than water. This is why the dry-erase drawings float to the top of the water.
In addition, the SD-alcohol-40 and resin, which are both water-insoluble, keep the drawing intact while it is floating on the water’s surface. The characteristics of these ingredients combined to cause the dry-erase ink to float on the surface of the water.
How Do the Components in Dry Erase Markers Make Them Float in Water?
Because the polymer resin used as the binder for dry-erase ink does not have strong adhesive properties, it will peel off the surface easily when the writing is submerged in even just a bit of water.
Speaking of buoyancy, the polymer is also less dense than water, which is why it floats. Just the force of buoyancy is enough to lift the dry-erase ink off the surface and cause it to float.
The resin made the ink hydrophobic, which allows it to stay isolated from the non-porous surface and the water. Then the SD alcohol-20 helps keep the ink together, thereby preventing it from dissolving. Meanwhile, the isopropanol keeps it from drying too quickly.
You can see all these ingredients in action even if you do not use water. Just look at the eraser you used recently for erasing dry-erase markers. You will still find the particles of ink completely separate from the eraser’s surface.
However, if you drop the ink into water, it will not float. What it does, instead, is it will dissolve into the water just like regular ink would. The reason for this is that the isopropyl alcohol has not evaporated yet. Isopropyl alcohol dissolves in the water quite readily.
You will need to follow a rather specific set of directions if you want to make a dry-erase marker float on top of the water.
How to Make Dry Erase Marker Float in Water?
If you want to learn how to make a dry-erase marker float in water, which is a fun experiment that you can do with your kids, the steps are quite simple.
Step 1: First, you need to get a porcelain or glass bowl and then draw whatever you want on its surface. Ideally, the drawing should have lines that are interconnected with each other. For instance, if you want to write your name, use cursive letters so that the letters are still together and readable after they float.
Step 2: Once the ink has dried, slowly pour water into the bowl. Make sure that you pour the water along the sides of the bowl so that you do not break up the dry-erase drawing. You will need to pour around 1 inch of water.
Step 3: Wait a minute or so and you will see the drawing gradually peel off from the bottom of the bowl and float up to the surface.
How Do Dry Erase Markers Work?
The ink that dry – erase markers use is similar to that used by permanent markers. In particular, they have the same components, namely:
Chemical solvents – In dry-erase and permanent markers, the solvent used is usually isopropyl alcohol. However, you can also find other brands that use other types of alcohol as solvents.
Color pigments – The pigments used by dry-erase and permanent markers are typically the same.
Polymers – This is where dry-erase and permanent markers differ greatly. Permanent markers use acrylic polymers while dry erase uses an oily resin silicone polymer. Also, instead of an adhesive, a dry-erase marker uses static charge to make the ink stick to the writing surface.
Because of the difference in the ways that the polymers are used by dry-erase markers, you can easily erase them off non-porous surfaces, like that of a whiteboard. This is also the reason why the ink peels off easily when submerged in water.
Why does dry erase marker float in water? The components and parts of dry-erase ink work together to make it magically float to the surface of the water. However, the primary reason is the quick-release polymer used in dry-erase ink. This allows the ink to “peel off” the surface and float to the water’s surface.
Now that you know why it happens, you should try doing this fun experiment at home with your kids. Even when you know why it is happening, it is still fun to watch.