The following is an except from Prisoners, Lovers & Spies: The Story of Invisible Ink from Herodotus to al-Qaeda, by Kristie Macrakis, One of my favorite invisible-ink stories, that didn’t make the ...

The expression “in our DNA” may have become commonplace in corporate parlance, but specialty ink maker Diversified Nano Solutions Corp. (DNSC) has devised a remarkable new way to apply it – literally ...

Researchers have developed a rewriteable paper coating that can encrypt secret information with relatively low-tech invisible ink -- water. A message printed out by a water-jet printer on a ...

Which invisible ink pens are best? Spies and conspirators have used invisible inks for millennia to send messages. In the modern age, invisible ink pens are an excellent way for grown-ups to ...

Invisible inks based on “smart” fluorescent materials have been shining brightly (if only you could see them) in the data-encryption/decryption arena lately ...

People have always wanted to communicate privately. There once was a time when regular ink was secret enough, because not much of the world knew how to read. Then literacy ruined it for everyone, and ...

Coded messages in invisible ink sound like something only found in espionage books, but in real life, they can have important security purposes. Yet, they can be cracked if their encryption is ...