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Just in time for Halloween...ink that disappears!

by Unknown User on 2018-10-31T15:06:00-04:00 in History & Sociology of Science, History of Art | 0 Comments

Unlock your inner spy. Our thermochromic ink will let you hide things you don't want others to see but then uncover them when you need to read them or see them

 

Here is the card before..............

Here is the hairdryer heating up the card..........

 

 

And here is the card after the ink disappears.........

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

As the card cools down...................

 

 

 

 

 

 

 


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