EP1001884B1 - Confidential document for laser or ink jet printer - Google Patents

Description

The technical field of the present invention is that of printing and more particularly that of the preparation of documents containing a confidential text. In modern life, there are all kinds of opportunities for writing documents containing confidential information that third parties, including printers and people responsible for delivering them should ignore. Only the recipient must take note. So such documents are sent by banks to their clients to disclose their credit card code to them, or by trustees to tell the occupants of a building what is the code to access it.

According to the prior art, the reverse side of such confidential texts is redacted, and often we also redact an envelope in which the document is located.

In the case of transmission of the credit card code to their customers, some financial institutions write it clearly in a registered letter or not, but this is not confidential since the code is known to the typist who writes it and that a third party can open and close the envelope without the recipient surrendering account of indiscretion.

Another financial institution uses an A4 format form which includes bottom left corner a pre-cut heel on which an adhesive label has been placed, carbonless, redacted on its front. The code is entered there using a printer at impact. When peeling off the label, the code appears and is readable by anyone indiscreet who, after reading, will replace the label exactly in its initial location, without the recipient being able to notice it. Confidentiality is therefore not guarantee.

Yet another financial institution sends more documents to its customers sophisticated which includes a first sheet kept by the issuer which includes a redacted area of intertwined letters and numbers and its back is fully coated with carbonless layer while the client receives a document in the form of a pocket glued on all four sides by a strip pre-cut in dotted lines. The front of the first copy, in addition to the emblem of the transmitter and the place of emission, contains an area or the customer's address and the reasons for possible non-distribution are printed, a small rectangular area redacted with interlaced numbers and letters intended to receive the code by carbonless duplication. The front of the second copy, inside the cover, therefore illegible before having broken the precut strips of the edges of the document, includes in particular a frame plumb with the redacted area of the front of the first copy where the code will be readable by the recipient. Finally, the back of the second copy, outside of the cover, is completely redacted to improve opacity. When IT prints the address on the first sheet, we find it on the first copy of the cover. When we also print by impact the confidential code on the redacted area, it is impossible to read it on the first copy of the cover, but it appears clearly as part of the front of his second copy.

Yet another financial institution uses a similar document, but still more sophisticated because the pouch contains another pouch to pull from the first. This, also redacted on the back of two sheets also contains borders pre-cut that must be torn to finally access the code that appears on the front of the second copy.

The prior techniques are therefore expensive and for some unreliable as to the confidentiality. In addition, the confidential text is used to print; printers impact that have become obsolete and are increasingly being replaced by laser or inkjet printers that do better work at lower cost.

A document according to the first part of claim 1 is known from AU-B-442,297. document contains a confidential inscription formed by covered surfaces ink or toner and should only be read by those authorized to read it. This document also has a redacted area on which an adhesive film, at least partially transparent, for laser printing or inkjet is glued. The adhesive film is at least partially detachable from the document. Confidential registration is printed with a laser or inkjet printer on the surface of the adhesive film. he becomes legible by separation of the adhesive film and the document at least in the area of confidential registration. The separation causes permanent changes to the document.

In the redacted area of the confidential document known to AU-B-4 442 297 is a non-stick area.

According to some achievements of the confidential document known from AU-B-442 297 the document has a tongue precut in its thickness taking care of leave attachments forming seals connecting the tab to the rest of the document. The authorized persons take note of the confidential registration by detaching the tongue precut by breaking the fasteners.

In the confidential document known to AU-B-442 297 we can glue the back of the tab on the transparent adhesive film.

The object of the present invention is to present a simple document in the manner of document known from AU-B-4 442 297, reliable as regards confidentiality.

The present invention thus relates to a Telque document defined in the claim 1.

According to the invention, the possibility offered by laser and jet printers is used. ink to print the signs and characters of the confidential text only to a certain percentage of coverage. When the coverage is 100%, the entire surface of the signs and characters is covered with toner or ink, and these appear very clearly at the risk of being able to be read notwithstanding the redaction and even the screen little dots. As the coverage of signs and characters decreases, i.e. the surface coated with toner or ink decreases, these become less apparent and it becomes increasingly difficult to read or guess them in the redactions.

According to an embodiment of the confidential document of the invention, it includes a tongue precut in its thickness taking care to leave fasteners forming seals connecting the tab to the rest of the document. Authorized persons read the confidential inscription by detaching the tab pre-cut by breaking the ties. It may also provide that the back of the tongue can stick to the transparent adhesive film. According to another realization of the document of the invention the confidential entry comprises signs and characters.

The new document of the invention allows traditional enveloping. He ... not has no excess thickness except that of the adhesive film for laser printing or inkjet that a person skilled in the art can make very fine, of a few tens of microns, and it is well suited to modern fast printing methods, laser printer or inkjet. Confidentiality can be taken to the extreme since whoever manipulates the printer can ignore confidential information such as codes, which it prints.

The very complexity of the prior art, and its non-adaptation to modern techniques prove that the present invention is not obvious to one skilled in the art art.

According to an embodiment of the confidential document of the invention, the redacted area of the document also has a pattern of small dots. According to the invention, is meant by point any inscription of small size because the usual circular shape of the points is not a feature of the invention. The presence of small dots has only to further hamper the reading of inscriptions made by laser printer or inkjet.

It is quite obvious that the percentage of coverage to guarantee the impossibility of revealing confidential signs and characters depends on the quality of both redaction and of the weft with small dots. This is why, the carcatéristique of the invention is here simply that the coverage of signs and characters is only carried out at a percentage less than 100%.

According to another embodiment of the confidential document of the invention, a film is used matt polyester adhesive for laser or inkjet printing which is well known by one skilled in the art.

In another embodiment of the confidential document of the invention, the tab pre-cut has no common edge with the edges of the entire document, and there thus forms a sort of island. This feature is important for ensuring perfect confidentiality because if the tab were to have a common edge with the document an intruder might try to read the confidential text by raising slightly the film tab.

According to another embodiment of the invention, the confidential inscription is printed in inversion, i.e. it is printed so that it can be read normally when you turn the document over on its back after removing the tab Pluck.

Following an embodiment of the confidential document of the invention, the adhesive film overflows the non-stick area (in which it has its partially suppressed stickiness) and there is glued to the paper support so that when the film is separated from the support, the film does not tear while the paper support is defibrated. We arrive at this characteristic by coating either the plastic film or the paper support, or both surfaces of a permanent adhesive whose peel strength is higher than that the resistance to tearing of the fibers which constitute the weft of the paper support, and by choosing a film more resistant to tearing than the paper support. Man's art will be able to choose both the adhesive which must be sufficiently powerful and the film which must be thick enough. What is unexpected and beyond the reach of ordinary skill in the art is the application of defibration of the backing of the backing paper as proof that an attempt was made to separate the film from its paper support and that the confidential registration may have been read. The recipient will notice an indiscreet reading of the confidential text since to do this, we will have to lift the film and defibrate the paper support, which will leave visible traces even if we tried to glue the paper back. Therefore, this final feature of the invention will deter any unauthorized third party from trying to read the confidential registration thus making confidentiality more reliable.

According to another characteristic of the confidential document of the invention, we have removed the adhesiveness of the film on the surface which corresponds to the redacted area in applying a non-stick substance to the film before applying the adhesive. This feature of the invention may be useful in preventing the recipient authorized to read the confidential inscription, to stick the film on any support. For example, the user of a bank card may have the bad idea of sticking the film on it to keep his code in mind whenever he uses his card. Besides that this practice is contrary to the recommendations of banks which advocate that codes be memorized and written down nowhere, the film can come off in the devices having to handle the card, especially ATMs, which can cause the failure.

According to another characteristic of the confidential document of the invention, the substance non-stick inserted between the film and the adhesive of the adhesive film is a silicone.

The present invention will be better understood on reading the example which follows.

EXAMPLE: Document transmitting the code of a credit card.

On sheets of A4 format at 80 g per m ² , the non-confidential inscriptions are printed with the laser printer and a block A, of rectangular shape, redacted and provided with a screen of small dots, 90 mm long by 30 mm high and located 15 mm from the top and right edges. During the same passage, a non-stick coating is deposited forming a block B of 76 by 20 mm located in the middle of block A.

Then, over the entire surface of paver A, a permanently adhesive film is applied. matt polyester for laser printing 50 microns thick. On the back of printing, on the back and in the middle of block B, we cut taking care not to start the polyester film, a C tab of 60 by 15 mm leaving eight fasteners which connect the tab to the rest of the sheet, 4 fasteners are placed at the four corners of the tongue, the other four are regularly arranged every 20 mm along the two long edges. The back of tab C is white and therefore does not have any registration.

This produces A4 format documents for use by financial institutions issuers to send each customer the secret code of their credit card. The attendant of the financial institution prints the name and uses a laser printer the addressee's address and, in block B and within the area delimited by the surface of the tab, its confidential code. This last impression is made from so that the surface of the printed figures is only 30% covered, so that it is impossible to read them on the redaction and the dot plot. The documents thus completed are put in envelopes and sent to customers. Upon receipt of sound document, each customer detaches the tab C by breaking the eight fasteners. Laser printing with 30% coverage of the digit area is sufficient to read them. But the customer will prefer to turn over the tab C and stick its back on the permanent adhesive of the polyester film because the reading of the confidential code will be much easier on the white background of the back of the tab C.

The present invention is in no way limited to the present example and to the explanations which preceded it and it also concerns all the achievements evident to man of art that flow from the spirit of the invention. As other examples, we can thus communicate, in addition to credit card codes, the confidential access code to the Minitel, the code of a Telecom card, a building access code, texts and reports more important classified secrets because nothing prevents increasing the size of the area confidential which contains the redaction, the laser film and the removable tab. The area could even occupy the entire surface of the A4 document, minus a border about 1 cm on all sides.

Likewise, the present invention is not limited to A4 format documents which is in no way characteristic of the invention or of a flat print. We could just as well use any other printing mode, especially continuous.

Claims (12)

1. A document comprising confidential writing formed by surfaces covered in ink or toner and which cannot be read except by persons authorized to read the writing and comprising a blocked out area on which an adhesive film, at least partially transparent and adapted for laser or ink jet printing, is glued, the confidential writing being printed with a laser or ink jet printer on the surface of the adhesive film, the confidential writing becoming readable by separating the adhesive film from the document at least in the area of the confidential writing and the separation causing permanent modifications to the document, the adhesive film having its adhesiveness partially suppressed in correspondence with said writing area in order to preserve the integrity and readability of the film during the separation, characterized in that the surfaces are coated with ink or toner with a percentage lower than 100 %, this percentage being a function of the quality and intensity of the contrast of the blocked out area.
2. The confidential document according to claim 1 characterized in that the document comprises a flap precut throughout its thickness with care taken to leave strips forming seals binding the flap to the rest of the document.
3. The confidential document according to claim 2 characterized in that authorized persons read the confidential writing by detaching the precut flap by tearing the strips.
4. The confidential document according to claim 3 characterized in that reading the confidential writing becomes easier by resealing the back of the flap onto the adhesive transparent film.
5. The confidential document according to any one of claims 1-4 characterized in that the formed confidential writing is comprised of signs and characters.
6. The confidential document according to any one of claims 1-5 characterized in that a small dot frame is presented to hinder the reading of confidential writing printed by laser or ink jet printers even more.
7. The confidential document according to any one of claims 1-6 characterized in that the adhesive film is a matte polyester film for laser or ink jet printing.
8. The confidential document according to any one of claims 2-7 characterized in that edges of the precut flap are never merged with those of the confidential document.
9. The confidential document according to any one of claims 1-8 characterized in that the confidential writing is inversion printed.
10. The confidential document according to any one of claims 2-9 characterized in that the adhesive film goes beyond the area in which the film has its adhesiveness partially suppressed and is glued onto the paper support so that when the film is disconnected from the support, the film does not tear while the paper support is defibered.
11. The confidential document according to any one of claims 2-10 characterized in that the adhesiveness of the film on the surface corresponding to the blocked out area is suppressed by applying an antiadhesive substance on the film before applying the adhesive.
12. The confidential document according to claim 11 characterized in that the antiadhesive substance inserted between the film and the adhesive of the adhesive film is silicone.