Sharpie Color Science

Everybody loves color!  It makes our world incredibly beautiful.  Color is what makes rainbows, flowers, and paintings so interesting.  Did you know that there is a lot of science in the colors you see around you? In this activity, you will explore the science of solubility, learn a bit about Sharpie markers, and create some beautiful artwork along the way. Let’s do some Sharpie color science!

Here’s What You Need

• White cotton T-shirt or white cotton cloth
• Sharpie Permanent Markers (assorted colors including black)
• Rubber Band
• Large Plastic Cup
• Dropper Bottle or Eye Dropper
• 70% Rubbing Alcohol

Here’s What You Do

Locate the area on your t-shirt or cloth that you want to decorate and place the opening of the cup directly under that section. Stretching the rubber band over the t-shirt and around the opening of the cup to secure it in place.

Secure your cloth with a rubber band.

Using one color of Sharpie, create a pattern around the center of the stretched fabric. You can draw lines, shapes, dots. Your only limit is your imagination. Now, select a different color and draw some new designs. If you like, you can use a third, fourth, or even fifth marker to draw some more things.

Use a Sharpie and your imagination to draw on the cloth

Using your dropper or pipette, slowly squeeze about 20 drops of rubbing alcohol into the center of your design. Watch as the rubbing alcohol is absorbed into the cotton fabric.  What happens? The ink spreads in a circular pattern expanding outward from the center. As it moves, it causes the colors in your design to spread and change.

Slowly drip the alcohol onto the center of your cloth

Once you are satisfied with your artwork, you can move to a new section of the cloth and start the process all over again. Try drawing a small square with each side being a different color. Use primary colors (red, blue, yellow) to draw a geometric shape and accent it with dots of secondary colors (orange, green, purple). You may also want to experiment with shapes like half circles and polygons. Be creative!

Try using different shapes and colors on your cloth

Here are a couple of things to keep in mind: Keep your patterns centered in the design area. Use small drops of rubbing alcohol and drip the alcohol slowly in the center of the design.  This gives the color an opportunity to spread outward from the center.

After you finish decorating your shirt, let it dry for 30 minutes. You may want to rinse the shirt in a solution of vinegar and water as a means of setting the colors. You can also heat-set the colors by placing the shirt in the dryer for approximately 15 minutes.

Use heat or vinegar to set your colors after you finish

SAFETY NOTE: Rubbing alcohol is flammable. Keep it away from any open flames or heat. This experiment must be conducted in a well-ventilated area, preferably outdoors or in a room with open windows.

The Science Behind the Sharpie Color

In addition to color mixing, this activity also explores the science behind solubility and molecules. Generally, we think of the ink in Sharpie markers as permanent.  This means that Sharpie ink will not wash off with water.  This is because the molecules in Sharpie ink are insoluble in water.  In other words, the molecules don’t mix well with water. However, Sharpie ink is soluble in rubbing alcohol.  This means that Sharpie ink will mix with alcohol.  In this activity, we use this important piece of information to create very unique designs on cotton cloth.  As the alcohol, also known as the solvent, soaks into the t-shirt it carries the molecules of colored ink with it.  Since the alcohol spreads outward from the point where you dripped it, it creates a beautiful circular pattern on the shirt.

Fast Fact

The Sharpie marker was introduced in 1964. Since then, it has been expanded into a wide product line and multiple colors. The Sharpie company as sold more than 200 million markers worldwide.