The Basics of Making Invisible Ink

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"The Basics of Making Invisible Ink"
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At some point in every childhood there seems to be some commonalities. It seems the wish of most children is to exchange secret messages that no one else can read or understand.  The idea of invisible ink is intriguing. It was not just for children, prisoners of war used saliva and sweat to write messages.  It is more than just writing in code. No one even knows it is there. So what are the basics of invisible ink?

Most invisible inks are made by using a simple substance that dries clear and then when heated reappears.  There are also some inks that become visible only under a black light. Some solutions become clear when other substances are painted over them.

The two best methods of writing with invisible ink would be to use a fountain pen and dip into the ink.  Or to recycling an old marker and make an invisible ink pen is an excellent option.  Other options to use as writing utensils are toothpicks, cotton swabs or paint brushes.

*Baking Soda
Take equal amounts of baking soda and water and mix.  Use the writing utensil of choice and write the message.  Allow it to dry completely.   The receiver of the secret message will need some water with food coloring added or grape juice and a paint brush.

The receiver will paint across the paper and the message will appear as soon as the mixture reacts to the grape juice or colored water.

*Lemon Juice
When life hands one a lemon, make invisible ink.  With this method write quickly as there is salt to apply while the message is still wet.  This works well for a big note with large letters.  While the lemon juice is still drying spread salt across the message.  Give it a minute for the salt to adhere then wipe it off.  

The receiver uses a wax crayon to color over the message and find what is written.

Write the message in simple straight vinegar and allow it to dry.

To see the message one has to add heat.  A heating pad warmed and turned on high will make the message appear in a matter of minutes.  Another method would be to hold the paper over a lamp until the heat penetrates and makes the message appear.

*Corn Starch
Take 1 tablespoon of hot water and mix it with 2 tablespoons of corn starch.  Stir it till the mixture is smooth and the corn starch is completely dissolved.  Write the message on a plain piece of white paper.  Allow the message to dry completely.

The receiver would make a potion of one part iodine and ten part water.  They would paint the paper and the message would appear in purple.

If a black light is an option for the receiver the message can be written with liquid detergent.  Almost any brand will work as long as it lists brightening clothes in the description Teenagers tend to use this to decorate walls and then add black lights.

Teach a little science with invisible ink basics.


More about this author: Trenna Sue Hiler

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