Are there inexpensive pens that can be used to make markings on paper that would show up if the documents are scanned or xeroxed?
I’m trying to google such a product, but I can only find invisible inks that can be used by an inkjet printer, or inks that do not show up if copied or scanned.
Um… wouldn’t all marks show up? What am I missing here? I run a high-speed scanning/imaging mail center. We capture everything.
If this is what you are getting at:
Highliters = trouble. If you highlite text, it can become a black bar. To counter this, we can use color, but that is soooo much slower than B/W. With color, the text and highlites show up.
ETA: I think you want marks that wouldn’t show up? You can do that, if you make marks in certain fields and can set your expensive scanning/recognition tools to ignore the marks.
Now I read again and am confused again.
.
Sorry, the key information is split across the subject and the body of the OP.
I would like a pen that uses “invisible ink” to make marks on paper that would only become visible on scanned or xeroxed copies of the original.
Think of hand-writing DUPLICATE on a contract or report, but the original would not show that marking. Only if it were reproduced by copier or scanner would the DUPLICATE be visible on the copies – the marks need not become visible on the original.
Many checks have a complex background with a slightly heavier pattern that forms the shape of the word ‘void’. It’s not dark enough to disturb the check, but shows up darker when you photocopy it.
It sounds like what you’re looking for is a pen with some sort of ink that does something similar.
Correct?
ETA: didn’t see your second post.
Yowza… I know of no such technology available in a pen, but the ink is available. I think you’ve figured that part out.
I’ll ask my imaging guy who lives for this stuff if he knows…
Precisely.
Something like this?
http://www.flintgrp.com/en/documents/Packaging-and-Narrowweb/Narrowweb/I_08_02_new.pdf
See the section on ‘special effects’ inks, specifically the Black IR.
I think that’s it. Around page 6 on PDF. Not numbered on the document.
*Black IR
– Visible or invisible in IR scanners
– Print barcode with an normal black ink and over print it
with a pattern of an IR invisible ink. The barcode will
now be readable with an IR scanner but impossible to
copy in a normal copy machine
– The IR invisible ink can be printed as a barcode, which
will give a non readable barcode in an IR scanner but a
copied fake would be readable
That’s the effect I would like to have.
Unfortunately there is no option to substitute specialized paper for this particular application. It has to be something that can be used to alter regular-ol’ bond paper.
I’m not sure if thisis what you’re looking for, but take a look.
This is ink that is visible to the eye but not to the copier, the reverse of what the OP requests.
This is ink that is visible to the eye *and *the copier, but not to an IR scanner, also not quite what’s needed.
I have not been able to find out how the copy-proof paper works but I suspect it may have to do with something in the texture of the paper, rather than some quality of the ink.
I’m starting to think that this is one of those things that if it were available, it’d be pretty easy to find. Oh well. Thanks for all your help.
From this thread in another forum, third post from the bottom, posted by someone who is in the business (quote is excerpted):
Couldn’t that be made to achieve the same effect as the OP requests though?
(May not suit the OP’s exact needs but…)
Print a design using a combination of normal and copy-invisible ink. When duplicated the special ink isn’t copied leaving behind a different result.
E.g. Print words in a line at the bottom of a document header and then fill in the void space on the same line with special ink.
It would look like a solid (decorative) line on the original but when photocopied the special ink would disappear leaving behind:
DUPLICATE - DUPLICATE - DUPLICATE
(Or do I need more coffee?) 
Very nice out-of-the-box solution! 
It wouldn’t work, the reason the color is “invisible” in copies is because a normal copier translates light blue to white. But you can’t write a message in black ink (or any other color ink) and then conceal it under a bar of light blue ink. It’ll just look like words on a sheet of light blue paper.
Colors are the basis of another copier trick. Some shades of red translate into black in a normal copier. So if you write something in black ink on red paper, you can read it but you can’t make copies of it because it’ll come out all black.
This is why I think the OP isn’t going to find what he’s looking for. These tricks depend on various colors that are all distinguishable to the eye but all turn into black or white in a copier. But to have a pen like the OP wants, you’d have to have some kind of ink that looks like plain white paper to the normal eye but somehow is turned to black by a copier - and that’s no going to happen with regular copier technology. Normal copying may make a bunch of different colors all look the same, but it never makes one apparent color split into different colors.
The copy proof paper I have seen involve one of two methods.
Fine micro printing that our eyes just blur out but are under sampled by the copier creating a pattern in the copy that our eyes do not see. Like in Telemark’s link
Low contrast back grounds that are easily visible to our eyes but are not picked up in black and white copiers. The tend to say something like “original document”
Pfft. Implementation detail… I’m an Analyst. 
Fair enough though – although I was thinking filling in voids rather than over-printing – but unless the colours were right on the edge of one going to white and the other to black in a copier it’s not actually going to work. (And it won’t be unreadable on the original unless the human can’t see the colour difference… so that’s not going to work…)… oh well.
Which may work with a copier and then fail with a scanner. No cite, just an old memory of reading an article by Jerry Pournelle from yonks back when he wrote for Byte where he was given some samples of copy-proof documents (low contrast method) and subsequently gave copies back to the creators after running them through a scanner rather than a standard copier.
I don’t know how a pen would do it (special pens are sold for precisely the opposite purpose – they don’t show up when photocopied or black and white scanned, since the ink color appears “white” to the sensor). I suppose it might be possible to find some ink that looks white to visible light, but is dark when viewed in the near infrared (that the copier/scanner is sensitive to), but I don’t know of such a creature. You might try experimenting.
As noted, the documents you have seen with a “Void” popup use a variation in the background pattern. You can do this yourself. Artist supply stores and drafting stores used to sell sheets of gray halftone patterns – generally a sheet of tiny dots printed in a pattern that, from a distance, make the backgroyund appear uniformly gray. If you cut out the words you want to show up from the sheet that you lay down in thebackground, then fill in those white spaces with slightly different halftone of the same overall gray level (substituting squares for dots, or even using the same dot pattern, but rotated by 45 degrees), then, provided you have done your work carefully, it will appear uniform gray to the eye. But when copied or scanned, the words will become visible.
In fact, nowadays you can probably write a graphics program that will produce a printed shee that will do this automatically.
You want something that will demonstrate if a document is original or copied, right?
Rather than invisible ink, how about a stick-on hologram. You can buy them off the shelf cheaply on eBay.
example: http://www.ebay.co.uk/itm/500-SECURITY-Hologram-Holographic-stickers-labels-/150656548080?pt=UK_BOI_Packing_Postal_Supplies_Labels_LE&hash=item2313d47cf0
You can possibly get them custom made with your own logo on, that will stop duplication.