Any of the following can serve as the acidic solution for the invisible ink: milk, vinegar, or lemon juice. The heat source can be a candle, a hair dryer, an iron, or even a lamp. All of these items should easily be found around the home or purchased at the grocery store.
Dispose of the liquid down the drain when you are finished. Do not use the liquid for anything else once you have used it for invisible ink.
It may be difficult to keep track of what you are writing because the writing will be invisible as well. If you write at a well-lit table you will be better able to see what you are writing while the ink is still wet.
Set the first paper aside and write more messages while you wait for the first one to dry.
Be extremely cautious not to light the paper on fire if you are using a candle. Adult supervision is recommended for this to avoid burns or other injury. If you are using a hair dryer, use the low heat seating and wave it across the paper until the words appear. If you are using an iron, use it on a low setting. To avoid burning the paper away, place a piece of parchment paper between the iron and the paper before rubbing the iron on top.
The wax will not stick to the salt in the ink and you will be able to read what is written! There is no exact amount of salt to use, just make sure the message is covered completely while the ink is still wet.
Most of these materials should be easily found around the house. You can purchase a black light at a local superstore or online.
For best results, try to make the writing smooth, avoiding bumps from the jelly.
You don’t have to wait for the jelly to dry completely before revealing the message.
All of these items should be found around the house or purchased at the grocery store.
The exact amounts of baking soda aren’t important as long as you have equal amounts of baking soda and water.
While the ink is still wet you can see it if you are working in a well-lit room.
When the ink is fully dry, you won’t be able to see anything on the paper. It will look like a normal blank sheet of paper.
Avoid getting the grape juice on your clothes because it can stain.
