Photography uses light to make a chemical change and create an image. The Anthotype/Sun Print activity in this issue of Celebrating Chemistry (located on pg. 11) is an example of a chemical change ...

The secret history of invisible ink. American Expeditionary Forces secret ink lab By signing up, you confirm that you are over the age of 16 and agree to receive occasional promotional offers for ...

An invisible coating allows the surface of pills or sweets to be marked with a low-power laser. A small UK company has developed a range of food additives that allow a low-power laser to mark the ...

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 ...

Erasable pen 's ink turns to white on black paper because the ink contains thermochromic dyes that are sensitive to ...

Pig’s bladder, gypsum, fig sap, alum and onion juice — there’s no eye of newt among invisible ink recipes, but blood of dormouse is fair game. By the end of science historian Macrakis’ nearly ...

So you want to open sealed envelopes without getting caught? Here’s the secret, according to one of the six oldest classified documents in possession of the Central Intelligence Agency: “Mix 5 drams ...

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 ...

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 ...