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 ...

When I was a kid, my friend had this pen with invisible ink. You could write a note with it and then the person you sent it to had a different pen that made the text show up. We though it was awesome ...

A water soluble carbon nanodot ink produces bright long lasting invisible prints with micrometer scale detail and high accuracy for secure and low cost applications. Fluorescent inks fade quickly ...

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 ...

Researchers at Xerox have come up with a way to use standard printers to add fluorescent words and images–analogous to ID marks on currency that are visible only under ultraviolet light–to ordinary ...

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 ...