This invention broadly relates to security and protection systems for documents subject to counterfeiting or falsification attempts and, more particularly, it relates to a combined synergistic system which, by exploiting the combination of various protection systems, each individually valid and effective, at least to a certain extent, enables a finished product to be obtained with an absolute security level or, anyway, a security level much higher than the security level achievable as a sum of the security levels of the individual systems.
As it is known, the documents subject to falsification or counterfeiting, such as the bank cheques, the banknotes and broadly all so-called value-papers are protected against counterfeiting and falsification attempts by various systems.
Employment of watermark is one of said systems. A further system provides for incorporating metal wires with the thickness of the paper.
Usually, for instance in printing banknotes as well as bank cheques, they try to realize certain combinations of drawings or patterns as well as of particular colors, the duplication of which should be difficult and almost impossible.
The above mentioned systems are specifically aimed at preventing counterfeiting attempts, for instance the production of false banknotes.
As the requirements of modern life increase and as also the printing and duplicating techniques become more sophisticated, as well as in view of the ever developing inventiveness of the criminal underworld, it can be said that a real hurdle-race is presently being run between the civil authorities, on one side, who endeavour to organize novel and more sophisticated means and expedients to prevent counterfeitings and falsifications and the criminal underworld, on the other side, that has even more versatile and effective means available to counterweight the effects of such expedients
A problem to be solved, for instance, is to prevent the amount written upon a bank cheque from being erased and/or modified.
US-A-4 033 059 provides an article suitable for use as a security document including the combination of a recording medium having an intaglio-printable surface and an intaglio imprint of spaced and raised inked pattern elements on the surface, wherein the imprint includes an image and an adjacent background each formed by pattern elements and wherein pattern elements in the image differ from the pattern elements in the background for producing a variation in contrast therebetween as the angle of the view of the imprint varies in at least one plane normal to the surface. The image is defined latent because it is normally invisible and transitory because it becomes visible only when it is viewed at particular acute angles of view.
US-A-5,396,559 discloses an anticounterfeiting security method in which a hologram is recorded as either a regular or irregular pattern of dots, through a dot screen which is in contact with a recording medium, thereby limiting the exposition to selected dots. When the hologram is viewed through a second screen which is a duplicate of the contact screen, except that some portions of the second screen are reversals of the contact screen, the reversed portions will show up as portions either lighter or darker than the surrounding areas, depending on the exact positioning of the second screen relative to the hologram.
EP-A-0 581 414 discloses a method for making an anticounterfeit latent image formation object comprising a main body, projections and recesses means formed on said main body in such a manner as to exhibit various kinds of patterns, in which said various kinds of patterns comprise straight image lines forming a pattern, a relief pattern or a combination thereof, a plurality of straight lines printed on an upper surface of said projections and recesses means at predetermined spaces
It is an object of this invention to propose a particular set or combination of expedients that, when individually considered, exhibit a high validity, but, particularly when they are in certain manners combined together, furnish an almost absolute security level to any papers that could be subject to counterfeitings or falsifications.
This invention specifically suggests to provide the concerned documents with two protection systems: a so-called OSI (Overt Security Image) system for "apparent" protections and a so-called CSI (Covert Security Image) system for hidden protections, the details of which will now be comprehensively explained to a suitable extent so as to be comprehensible and applicable by persons skilled in the art.
This protection system comprehends the protection against falsifications and colour photocopies as well as the protection of the data amenable to be modified.
I. The protection against the falsification and the colour photocopies is realized, according to this invention, by adopting printing processes that, combined with particular drawings and particular etched patterns, utilize the light reflection effects in order to impart a differentiated evidence to some details of the drawing, in such a manner that, by means of small movements, a detail that initially appears to be optically positive becomes negative and vice versa.
This protection can be easily checked not only by a person skilled in the art, but also by a user having no particular training, because it is inherent in quite evident manner in the image itself.
As a matter of fact, this printing technique is quite different from the latent imaging technique as presently practiced in the value-paper field, consisting of an image hidden in the drawing (as it is implicitly comprehensible from the term "latent"), such latent image being only evidenced when it is observed under certain angles and only when it is illuminated by grazing light. In other words, the effect is hidden and it is made visible only under determined conditions, only known to persons skilled in this specific field.
The technique according to this invention can be assimilated to the technique of holograms in which the image is not hidden, but it is in any manner and under any observation angle apparent, but, when its supporting sheet is displaced, the image varies thereby exhibiting a "holographic effect".
Such a technique can be performed by:
This technique as adopted in this invention distinguishes from the holograms which are overposed on the paper and, as such, are removable therefrom and reapplicable to another document, and it allows to obtain an effect directly incorporated with the paper itself, without any possibility that it is removed and reapplied to another document.
The above mentioned holographic effect, that is quite visible and identificable by anyone, is obtained by a printing process, namely a chalcographic printing process. It is carried out by performing engravings in the printing plates and subsequently by filling said engravings with ink, said ink being subsequently transferred to the paper by application of a very high pressure (as typically employed in chalcographic printing machines) that deforms the paper so as to force it to penetrate into the tiny engravings of the plate, with contemporaneous ink transfer. At the end of the process, the plate segments that have been filled with ink transfer the latter to the paper. These segments will have a relief that can be perceived also by the touch, provided that the engravings realized in the plate have a sufficient depth.
The behaviour of the process will be now more detailedly explained: if we consider two parallel segments, namely a set of parallel lines, a set of grooves will be observed on the plate and, consequently, upon said transfer, a set of ridges will be present on the paper, said ridges having vertical walls that are as much high as the engravings are deep. If these walls have a certain colour and the paper is of a different colour, when they are observed from above, the perceived colour is the sum of the colour of the walls (for instance, sky-blue, if a sky-blue ink has been used) and of the colour of the paper (for instance, yellow, if a yellow paper has been used), and consequently the observed colour will be green (because, in the additive colour technique, the sum of a yellow colour and of a sky-blue colour furnishes a green colour). As soon as the observation point is displaced from the vertical line on these grooves, the bottom of the grooves will be less visible and the walls will become more visible, so that in the sum of the two colours (the colour of the bottom and the colour of the walls) the relevance of the yellow colour will decrease, while the relevance of the sky-blue will increase, with resulting different and varying colour. If the paper sheet is rotated in various directions, a variation of colours will be observed.
Assuming that patterns different with respect to one another are inserted, having grooves that repeatedly cross themselves and have varying inclinations, then the holographic effect is assured.
Still other variations can be obtained by means of ridges of variable heights, obtained by realizing engravings of variable depths in the printing plates.
In addition, particular effects can also be obtained by treating the paper bottom so as to obtain a more relevant reflection of the light, thereby making the concerned surface particularly specular with respect to the light rays, by means of printing processes.
As far as the objects of this invention are concerned, it is sufficient to specify that such kind of printing process provides for a dense succession of tiny grooves that are not individually discernible and have various depths, with variously inclined flanks.
II. In the frame of the OSI protections, the protection of modifiable data, such as the serial number, according to the proposal of this invention, is obtained by causing the serial numbers, or broadly the data it is desired to protect against any alteration, to be printed for one half on the positive band and for the other half on the negative band.
The printing colours as used in this invention can have a high coverage figure or can be transparent, so as to achieve the following effects.
I. This protection system according to this invention provides, in the first place, for drawing according to predetermined patterns all those parts that it is desired to protect against erasures, for instance the Serial Number of bank cheques, or any writing it is desired to make alteration resistant, and like. This drawing step, which practically entails embossing of the paper, can be carried out either before or after the serial numbers have been inserted. The latter procedure is surely more effective, in view of the fact that it deforms the characters themselves of the printed serial number according to the embossing pattern. The characters become extremely difficult to be erased, because the ink is absorbed in the depth of the deformations and it becomes unreachable not only by abrasive mechanical means, but also by chemical solvents.
II. In the second place, this protection system based upon latent images provides for inserting, before the standard magnetic band of certain documents, for instance, a letter in CMC7 characters, that can be magnetically read by means of an algorithm, possibly an intelligent algorithm, previously agreed upon with the client. Since the magnetic band usually provided in security bank documents is read by. running the document through a magnetic reader, it can be said that the magnetic band "flows" through the magnetic read and a character applied before the magnetic band in the running direction through the reader in effect is "upstream" thereof.
This algorithm can be inserted into electronic computers and it can be varied, for instance, according to pre-established number ranges. Only by way of exemplification, the case can be mentioned of a client with whom it has been agreed to utilize a letter as suffix 13 of the serial number, according to the following scheme, that is one of the innumerable possible schemes:
In a variation of this system, the above mentioned letters can also be illegible with naked eye, so that only magnetic readers can decode them. As far as documents are concerned that are passed through readers not provided with the necessary software needed for recognition of such letters, the position of the literal or numeric algorithm is such that these documents are anyway read, without interferences or noise caused by the concerned literal suffix .
C. As above mentioned, the algorithm can also be intelligent and such that it can be computed only by an electronic computer and it can be changed according to ranges previously agreed directly with the interested client. One of the innumerable intelligent algorithms can be only by way of exemplification as follows:
D. Aiming at avoiding any problem in respect of the inter-bank agreement connected with adoption of the CMC7 standard, the approach has been adopted to eliminate the blank space existing between the serial number and the number representing the bank code and the so-called CAB code (this blank space was necessary when the above mentioned codes were applied in successive stages and, therefore, a blank space was needed to accommodate for the tolerances and for preventing the two concerned codes from being overlapped). When said codes are applied in a single stage, this blank space in no more needed, so that the serial number can be displaced rightwardly by one figure space and the control algorithm is inserted into said blank and now available space.
III. Within the frame of the CSI protections, it is proposed to adopt a particular ink invisible with naked eye, which is made permanently visible upon being contacted with particular materials, for instance bleach. This system can be very useful both for checking the validity of a document, namely to ascertain that a document is not false, and for evidencing the presence of hidden information, for instance the win or an award (a kind of so-called "scrape-and-win" that, in this case, becomes "smear-and-win").
IV. Still in the frame of the CSI Protections and in connection with documents the circulation of which is to be strongly restrained, for instance the negotiability of bank chaques, it is suggested to provide for irreversible removal of a portion of the document, for instance a triangle portion of the top right corner of it, as it is analogously effected in the banks in the upper left corner, to indicate that the document is no more publicly negotiable, or a suitable punching, also in this case an irreversible punching. This expedient can be complemented by adding, in the portion to be cut off or removed, a value-paper pattern having lines very difficult to be re-aligned after cutting, so as to defeat any attempt to recompose the small triangular removed portion.
The preferred embodiments of this invention have been described and a number of variations have been suggested hereinbefore, but it should expressely be understood that those skilled in the art can make other variations and changes to the details and construction particulars, without so departing from the scope of the appended claims.