DIY Invisible Ink Craft & Experiment

Invisible ink invites discovery. Secret messages are great for treasure hunts and playing detective and making your own DIY invisible ink is the ultimate science lesson in disguise! Learn two different ways to mix up your own batch of this transparent fun with just one or two ingredients each.

Lemon Juice Invisible Ink

Supplies:

• ½ lemon
• Water
• Bowl
• Spoon
• Cotton swab
• Light source

 Steps:

1. In a small bowl, squeeze the juice from half a lemon.
2. Add a spoonful of water.
3. Stir.
4. Dip a cotton swab into the mixture and write your message on a white sheet of paper.
5. Allow to dry.
6. To reveal the message, gently wave the paper over a light source, such as a light bulb or a small flame.

Milk Invisible Ink

Supplies:

• Milk
• Bowl
• Cotton swab
• Light source

Steps:

1. Pour a small amount of milk into a bowl.
2. Dip the cotton swab into the milk.
3. Write your message on a white sheet of paper.
4. Allow to dry.
5. To reveal the message, wave the paper over a light source.

How It Works:

Lemon juice and milk are both mildly acidic and acid weakens paper. The acid remains in the paper after the juice or milk has dried. When the paper is held near heat, the acidic parts of the paper burn or turn brown before the rest of the paper does.

Note: Be careful not to touch the paper to the light source so it doesn’t catch on fire when revealing the lemon juice or milk inks.