Ink-Credible Secrets Behind Invisible Ink
By Kym Moore
The term invisible ink sounds like an oxymoron doesn’t it? What would constitute invisible ink becoming “invisible,” then visible? Why on earth would you want to use something that you naturally can not see? If thoughts of invisible ink sound like something you would watch in a James Bond movie or during one of a magician’s incredible disappearing tricks, you are not too far off from the truth.
Invisible ink is a substance that is either invisible immediately on or after application and can be visible by some other means. Invisible ink has been linked to espionage and is probably classified as the most popular form of steganography (communication by using hidden messages or codes).
Who is the mastermind behind these secrets? Pliny the Elder (Gaius Plinius Secundus), who was a Roman officer and writer is the instigator behind the origins of invisible ink. According to an excerpt from The Code Book: The Secret History of Codes and Code Breaking by Simon Singh, as far back as the first century A.D., Pliny the Elder explained how the milk of the thithymallus plant could be used as an invisible ink. Although transparent after drying, gentle heating chars the ink and turns it brown. Many organic fluids behave in a similar way, because they are rich in carbon and therefore char easily.
There are two types of invisible ink:
Once invisible ink dries after application to a writing surface, it should appear bland and begin to blend into the texture of the surrounding material. According to the type of invisible ink used, it can be made visible by different methods such as heat, application of a chemical or by viewing under an ultraviolet light. Among some of its other applications, invisible ink may be used when stamping hands for event re-admission, manufacturing identification or to mark property for recovery purposes, in the event of a burglary.
Invisible ink should not be used on ruled paper since it could cause altering or streaking the color of the lines. It should not be used with glossy or very smooth paper since the sizing of this type of paper prevents ink from being absorbed deep into the paper, making it easily visible. Commercial inks are available for non-porous surfaces that are visible only under ultraviolet light.
Toy invisible ink pens have two tips; one for writing and the other tip for developing the ink. Invisible ink can be used sometimes to print sections of pictures or text for children to play with. Included with these books are decoder pens that children can rub over invisible parts of the pictures or text, revealing answers to questions or completing missing parts of a picture.
Invisible ink is also used in computer inkjet printers and is usually visible under ultraviolet light. This is used for printing information on business forms to avoid cluttering the visible contents of the form. Some U.S. Postal Services use UV invisible ink to print bar codes on mailed envelopes giving routing information for use by mail handling equipment.
Invisible ink is rarely used in art. Artists who use it in conjunction with other paints to create a variety of effects, display their art using UV lights. Invisible ink with florescent properties can be obtained in a variety of colors and formulas to be used on non-porous surfaces like glass or plastics.
There is an element of meticulousness involved with sending an embedded message written with invisible ink. Certain precautions are taken into consideration when secrecy is a premium. Invisible ink reaches beyond the scope of the naked eye. To see or not to see…that is the question!
Kym Gordon Moore is a public relations strategist for budget conscious new authors and coordinates creative marketing packages for her clients. She is fascinated with writing instruments, machines and other noteworthy objects that contributed to the progression of the art of writing. Many of her articles, essays, short stories and poems appeared in a variety of magazines, newspapers, ezines and anthologies. Visit her website at http://www.kymgmoore.com.