Please identify two chemicals for me--that are readily available and
non-toxic--that work together to produce the following effect:
Chemical #1 is used in a pen to write out a word on a piece of paper.
The word is invisible (as though it were written in water).
Chemical #2 is used in a pen to rub over the area where the word was
written. The word immediately becomes visible. (Ideally, the paper
surrounding the word is unmarked.) Shortly (in a matter of seconds,
not minutes) the word fades away and once again becomes invisible.
It would be great if this process could be repeated a number of times.
Thanks in advance for your efforts |
Request for Question Clarification by
pinkfreud-ga
on
08 Aug 2003 20:12 PDT
Is this the kind of info you're looking for?
"Mix some cornstarch and water over a burner for a bit and then let it
cool and write with it. After it dries, to reveal the message sponge
the paper with a solution of iodine and water. You will get dark blue
writing on a light blue paper. Substitute lemon juice for the
cornstarch and you'll get white text on a light blue background.
But, suppose it is Valentine's day and you want to send your
sweetheart a love message in red. That will be a bit harder, but it
can be done with varying success. The element you will need is called
Phenolphthalein. That likely doesn't sound like anything you've ever
heard of, but it is found in most over the counter laxative pills!
You'll need a box, and be sure it does have Phenolphthalein in it.
If the pills have gotten have a coloured coating, you'll have to
scrape that off. Take five or six tablets and crush them using a
spoon. Then add a few tablespoons of water and mix. This is your ink
and you may write your message.
When you are ready to reveal your message (after it has dried.)
you will need to mix four tablespoons of hot water with four teaspoons
of washing soda (you could also use ammonia,) . Get a plate and pour
some water in it, lay the paper on the plate. You want the paper to
be really saturated with water. Next, carefully dribble the washing
soda solution onto the paper, allowing the drops to spread over the
entire surface. Be careful to not touch the paper while it is wet or
it will smear your message. The writing should appear in reddish
pink."
http://starryskies.com/articles/dln/6-01/invisible.html
If the sort of chemical reaction described on the site linked above is
of interest, I'd be glad to try to find similar material.
When you say "It would be great if this process could be repeated a
number of times," do you mean that the same paper could be rendered
blank and reused over and over? If so, I very much doubt that this can
be done simply, since the residues of the previous writings will
remain.
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Request for Question Clarification by
pinkfreud-ga
on
08 Aug 2003 20:19 PDT
I've just re-read your question, and I now see that you want the
second chemical to render the writing visible for only a few seconds.
The chemicals mentioned in the link I posted above will not do that.
Sorry for the misunderstanding.
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Clarification of Question by
alwayscurious-ga
on
09 Aug 2003 07:27 PDT
Hello again, pinkfreud. You may not recall, but you helped me once
before. I appreciate that you're taking a shot at answering this
question. Thank you.
Clarification: Yes, I do want this reappearing and dissapearing effect
to repeat a number of times. I recognize that it may not be possible
to repeat it forever, but anything more than ten times would be
satisfactory.
I found a website that offers a product with the features that I'm
looking for. They are, however, unresponsive to my e-mail inquiries.
See: http://www2.sdia.or.jp/~comtec/Opportunities/TradeOpportunities.htm
=-=-=-=-=-=-=-=-=-=-=
Technology: Come & Go Inks
Invisible ink (available in red) is printed onto paper, either with
or without accompanying visible offset text/images. When applicator
pen is rubbed over the invisible ink it immediately becomes visible
and then fades to invisible again, within a minute or so. User can
repeat process 10-15 times.
Current Applications: Activity books/sheets for children and adults.
Study materials for children and adults.
=-=-=-=-=-=-=-=-=-=-=
Another way to ask my original question: What chemicals are used in
the Come & Go Inks activity books? Or more generally, what chemicals
could be used to achieve the same effect?
Another point of clarification. When I ask for chemicals that are
readily available, I don't restrict that to mean milk or lemonade,
etc. Any chemical available through a chemical supply house is fine. I
just don't want to have to mix, boil, distill, or otherwise process my
own solution.
Thanks again.
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Request for Question Clarification by
pinkfreud-ga
on
09 Aug 2003 14:49 PDT
I've come up dry (to use an ink metaphor), but I hope another
Researcher will be able to find chemicals that will enable you to do
this.
It would help a Researcher to know one more thing, I think:
When you say you don't want to have to process your own chemical
solution, would this be the case even if, for example, it was
necessary to stir a powder into a liquid, or other very simple mixing
procedure?
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Clarification of Question by
alwayscurious-ga
on
09 Aug 2003 15:51 PDT
Thank you for your efforts, pinkfreud.
You asked whether I would find it satisfactory if it was necessary to
stir a powder into a liquid, or other very simple mixing procedure?
Answer: That would be ok. I just don't want to have to get under a
hood with goggles and and beakers to brew my own concoction.
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