General Question

elbanditoroso's avatar

Do white boards remember?

Asked by elbanditoroso (33064points) April 24th, 2017

An old trick in detective shows and movies was that a person could rub a pencil over the top of a notepad of paper, and sometimes the message (on the sheet that had been torn off above) could be read because the original writer had pressed so hard.

But people don’t use notepads as often now. Lots of places use those whiteboards with various colored markers.

Is there residual color memory? Could a forensics person piece together what was written on a whiteboard even if it had been erased, based on some invisible chemical remnants?

Observing members: 0 Composing members: 0

3 Answers

zenvelo's avatar

There is if it is not cleaned properly. But if you use cleaning fluid and an eraser, it is gone as if it was chalk on a blackboard.

LuckyGuy's avatar

I agree with @zenvelo. The color stays there if you only wipe it with a dry cloth or tissue or use only water. The true dry erase solvent uses alcohol as the main ingredient. (Some use vinegar). That dissolves the ink and smears it when a paper towel or eraser goes over it.

Also a new dry erase marker will dissolve the writing underneath it. Try the experiment. Draw some vertical lines . and let them sit for a day. Then draw some horizontal lines with a new marker and lightly erase them. You will see clean white spots at the intersection of both lines.

That said, if they are willing to spend a lot of money and time forensic scientists can read anything. See Archimedes Palipsest. A lead researcher on this project spoke at one of our meetings and explained how they did it. Incredible!

2davidc8's avatar

Some advanced high-tech whiteboards that can be used for teleconferencing have internal memory, just like copy and fax machines. So, their memories could be accessed, even if the surface has been “erased”.

Answer this question

Login

or

Join

to answer.

This question is in the General Section. Responses must be helpful and on-topic.

Your answer will be saved while you login or join.

Have a question? Ask Fluther!

What do you know more about?
or
Knowledge Networking @ Fluther