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How to Make Magic Appearing Ink at Home With Detergent

Invisible ink has a long and interesting history. It has been used by spies to send secret messages in times of war. Prisoners have used invisible ink to plan illegal activities. There are many different methods and substances that can be used to write messages on seemingly blank sheets of paper. Using detergent to make invisible ink is one of the most interesting, because the message remains invisible even after you have read what is written.

Things You'll Need

Laundry detergent
Water
Small bowl
Paintbrush
Toothpick
UV light

Instructions

- 1
  Mix 1/2 cup of laundry detergent and 1/2 cup of water in a small bowl. Add more soap if you want your message to appear brighter. Use a type of laundry soap that contains "brighteners," which just means that it contains phosphors, a synthetic phosphorescent substance.
- 2
  Dip a small paintbrush in the homemade soap ink, and use it to write on a blank sheet of paper. Use a toothpick to write with if you want thin lines. Set the paper on a flat surface to dry.
- 3
  Turn off all the lamps and overhead lights, and shut the curtains to get the best effect. Turn on a UV light, and hold it up to the sheet of paper to read what you have written. The message will glow very brightly because the phosphors in the detergent absorb the invisible ultraviolet light and emit light that is visible. The message will disappear again in regular light.

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