FR2677676A1 - SECURITY DOCUMENT CONTAINING AN OPAQUE WIRE HAVING IRIDESCENT BRANDS. - Google Patents

Abstract

Security document containing a security thread visible in transmitted light and appearing at the surface of the document in determined places called windows. The thread (P) is opaque and on at least one face has iridescent marks (I) appearing at least partially in at least one of the windows on at least one face of the document. The background colour of the thread is that of the part of the document where it will be introduced. The iridescent marks are preferably present on the thread noncontinuously, preferably at uniform intervals spaced at a distance which is equal to approximately that of the windows. Application to paper for bank notes.

Description

SECURITY DOCUMENT CONTAINING AN OPAQUE WIRE HAVING BRANDS

iridescent

  The invention relates to a printable security sheet for the production of banknotes and other valuable or security documents; this sheet containing at least one element of

  security, for example a security thread.

  It is known to authenticate banknote papers in particular to incorporate a security thread The security thread is often made of a transparent polyester thread covered with a

aluminum layer or printed.

  This wire can be visible in transmitted light and invisible in

  reflected light, as described in EP-A-279,880.

  High-performance technologies such as color photocopying or other high-resolution printing techniques now make it easy to counterfeit valuable documents or papers. To counter these counterfeits, documents have been created that contain a security thread that appears on the surface of the document in certain places called "windows" and this, on

at least one side of the document.

  Methods for making such documents are described by

  for example in EP-A-59056 and EP-A-229645.

  If a metallized wire is incorporated according to these methods, in transmitted light, the wire appears as a dark line on each side of the document; in reflected light metal parts are observed

shiny in the windows.

  However, it is necessary to make it even more difficult to counterfeit documents containing security threads

  appearing in windows In the patent application EP-A-

  400902 discloses a security paper containing a security thread which has in each window at least two metal parts which form repeating patterns along the wire and such that these two metal parts are of different colors This wire is made in particular by creating non-continuous metal parts on one side of a wire which carries on the other side a continuous layer of a metal of different colors

non-continuous parts.

  The Applicant has found that a security document, containing a security thread which appears on the surface in windows, can be made with greater security by using an opaque security thread and which has, on at least one face, iridescent marks that appear at least partially in at least

  one of the windows on at least one side of the document.

  The fact that it contains iridescent marks protects the document from reproduction by photocopy and makes it possible to authenticate it in reflected light by observing the face of the document where there are the windows. The fact that the yarn is opaque makes the yarn observable in the form of a dark line in transmitted light and thus makes it possible to authenticate the document in transmitted light; iridescence

  is not observed when looking at the wire in transmitted light.

  Preferably the yarn will have a background color color

  similar to that of the part of the document where the thread will be introduced.

  Since the thread has the same color (or a color close to it) as that of the part of the document containing it, it merges with the

  document and therefore can not be reproduced during a photocopy.

  The iridescent marks may be present on the yarn intermittently and preferably at regular intervals spaced at a pitch equal to about that of the windows. Preferably the marks go from one edge to the other of the yarn in the cross direction. also be present in the form of at least one continuous band on

the length of the wire.

  These two possibilities (continuity discontinuity) can be combined. We can use either a single type of iridescent marks, or several types of iridescent marks that are differentiated by their iridescence, that is to say by the colors they produce.

under given angles.

  Iridescent marks should preferably be chosen so as to have

  a good contrast with the background color of the wire.

  As a support for the safety thread, it is possible to use colorless polyester optionally colored in bulk (white being considered as a color), the polyester having mechanical and chemical properties well suited to the application of security threads. The base wire is covered on one or both sides with an opaque layer. This layer preferably has a color close to that of the

  part of the document o will be incorporated the thread.

  This layer can be provided by a coating or by printing (for example by gravure) of a plastic thread (such as polyester) and in quantities so as to have a yarn whose final opacity is greater than or equal to that of the sheet o It will be incorporated. The iridescent marks are put on one or both sides of the film However, it is more advantageous to arrange the iridescent marks in double-sided so that these marks are present in the windows Indeed, when introducing a wire into a document by an industrial process, the thread tends to twist and so it is not always the same face of the thread that

  appears for a given face of the document.

  It may also be advantageous to use a yarn in the form of a complex consisting of at least two laminated yarns and comprising

each of the iridescent marks.

  The double-sided presence is also interesting if you want

  make documents with windows on both sides.

  Preferably, the iridescent marks are deposited by

gravure or silkscreen.

  The iridescent marks may for example be made with an iridescent mineral pigment such as a mica coated with titanium dioxide or with a plastic pigment composed of a special stack of films producing an iridescent effect when the pigment is observed at an angle; the pigments are mixed with a binder

  transparent which has a good adhesion with the material of the film.

  The film is then cut into strips which have a width of preferably between 0.8 and 2 mm.

  wide may be suitable for the invention.

  The object of the invention is also to provide a security document containing a security thread detectable both visually and on a machine

sorting.

  On a sorting machine, for example, documents are detected by measuring the electrical conductivity of the safety wire or by capacitive measurement related to the presence of the wire (see patent FR 1570807). For such detections, the wire must comprise electroconductive portions. In the case of conductivity measurement, the electroconductive part must be continuous all along the wire. The wire is made conductive by adding an electroconductive layer to at least one of the faces of the base wire. can use a metal layer produced by vacuum deposition of an electroconductive metal (aluminum, chromium, nickel for example) or by coating or printing an electroconductive ink (metallic ink or carbon black ink by

example).

  The conductive layer (s) are masked by covering the two faces of the wire with at least one layer, preferably having a color similar to or identical to that of the document where the security thread will be incorporated. Iridescent marks are then made on

  one or both sides of the wire according to the invention.

  One can also detect a wire on a sorting machine thanks to the magnetism of the wire In this case, it is necessary to make the magnetic wire by bringing a magnetic element It can for example make the magnetic wire by depositing a layer of metal oxides (oxide of iron

for example).

  As for the thread and in accordance with the invention is mask

  then the magnetic layer and wear iridescent marks.

  It is also possible to combine the electroconductive layer on one side of the

  wire and magnetic layer on the other side.

  The invention is not limited to detection by measurement of electrical conductivity or capacitance or magnetism; it is only necessary that the colored layer and the marks

  iridescent do not disturb the detection.

  To make a security thread comprising a detectable element on a sorting machine, in particular an electroconductive or magnetic sorting machine, it is possible to use a complex yarn, as described above, consisting of at least two yarns and such that the detectable element is This prevents the layers or bands of this element from cracking (the discontinuity of an electroconductive layer is troublesome if it is desired to measure its conductivity). This complex can be obtained by laminating for example two films "iridescent marks / colored layer / polyester yarn / layer of a detectable element on machine // adhesive // polyester film

  / colored layer / iridescent marks.

  The colored layers and the iridescent marks can be made after gluing of the two films; each film may comprise a detectable layer; the adhesive may comprise a material

detectable.

  The complex can also be obtained by incorporating a detectable sheet between two films; the colored layers and the iridescent marks are preferably made after incorporation of the detectable sheet The detectable sheet can be incorporated

  between the two films, especially by gluing.

  To detect the wire by measuring the electrical conductivity, a sheet of aluminum can be used as a detectable sheet.

example.

  The printable sheet according to the invention is based on cellulose fibers; it may optionally comprise synthetic fibers It may comprise other authentication or tamper elements well known to those skilled in the art (watermarks, fluorescent fibers, chemical agents sensitive to solvents, acids, bases, oxydo-reducers). The following nonlimiting examples of the invention, with reference to the appended drawings, will make it possible to better understand how

realized the invention.

  Figure la shows a wire according to the invention comprising transverse iridescent strips. Figure lb shows the wire of Figure la in cross section. FIGS. 2 to 5 show other embodiments of the wire

according to the invention.

  the wire of FIGS. 1a and 1b consists of a polyester strip P coated on one side with an opaque colored layer C and on one side with iridescent marks. These iridescent marks are present on the yarn intermittently and at regular intervals. spaced at a pitch e equal to about that of the windows of the sheet in which the wire is intended to be introduced These marks go from one edge to the other of the wire in the cross direction In Figure 1 these marks are bars transversal, in Figure 2 these marks

are characters.

  According to another embodiment shown in FIGS. 3 and 4, the marks are present in the form of one or two strips

continuous over the length of the wire.

  FIG. 5 shows a wire according to the invention which

  presents discontinuous and continuous combined marks.

EXAMPLE 1

  On one side of a 12 mm thick transparent polyester film, an opaque white layer made from a white mineral pigment, coated titanium dioxide, is deposited using a MEYER No. 1 bar. a vinyl resin and dispersed in methyl ethyl ketone. The composition is deposited in an amount such that the opacity of the

wire of 88 photovolts.

  On the other side of the white coated polyester film, discontinuous iridescent marks are deposited, at regular intervals, by

  gravure (as in Figure 1).

  The iridescent composition comprises, in dry iridescent substance: 60 parts mica coated with titanium dioxide

  with yellow-green iridescence.

  vinyl polymer binder: 40 parts

  The film is cut into strips 1 mm wide.

  The yarn is introduced into a white paper sheet (opacity 85 photovolts) according to the method described in patent EP 59056 and such that the iridescent marks appear in the windows at the

paper surface.

  In transmitted light, a continuous dark wire is observed In reflected light, only the iridescent marks are observed at an angle

  approximately 45 degrees in the document windows.

  Iridescent marks have good resistance to circulation.

EXAMPLE 2

  One side of a 12 μm thick polyester film is metallized by deposition (under vacuum) of a continuous layer of aluminum. On each face of the wire is deposited the opaque white layer described in Example 1. white layer, we print brands

  Iridescent yellow-green (see Example 1) in continuous strips.

  Iridescent marks are then printed with pigments having a pink iridescence, discontinuously at regular intervals and as they form an angle of about 450 with the

marks in yellow-green.

  The film is cut into wires 1 mm wide, and such that the iridescent marks in continuous strips are centered on the middle of the

  wire and of a width less than that of the wire.

  The yarn is incorporated in a white paper according to Example 1.

  The same observations are made as in Example 1.

EXAMPLE 3

  6 gm aluminum foil is glued between two

  transparent polyester films of 6 Dim thick each.

  We cover each face of the complex obtained with the white layer

made according to example 1.

  One or both faces are printed by gravure printing with the iridescent pigments used in Example 1. The complex obtained is cut into wires 1.2 mm wide. The complex is incorporated.

  obtained in a white paper as in Example 1.

  In transmitted light, a continuous dark wire is observed. In reflected light, iridescence is observed in the windows at the surface.

paper.

  The wire can also be detected on a sorting machine by measuring the conductivity or the electrical capacitance of the document obtained according to the invention.

Claims (8)

  1 Security document containing a security thread visible in transmitted light and appearing on the surface of the document at specific locations called windows, characterized in that the thread is opaque and that it has on at least one face iridescent marks appearing at least partially in at least one   windows on at least one side of the document.   2 Security document according to claim 1, characterized in that the wire has as a background color that of the part of the document o it will be introduced.   Security document according to one of claims 1 or 2,   characterized in that the iridescent marks are present on the yarn intermittently, preferably at intervals   regular spaced by a step equal to that of the windows.   Security document according to one of claims 1 or 2,   characterized by the fact that the marks are present in the form   a continuous band along the length of the thread.   Security document according to one of Claims 1 to 4,   characterized by the fact that the thread has iridescent marks different iridescences.   6.Safety document according to one of claims 1 to 5,   characterized by the fact that the iridescent marks are present double-sided on the wire. he   Security document according to one of claims 1 to 6,   characterized by the fact that the security thread is a complex of at least two sons.   8 security document according to one of claims 1 to 7,   characterized by the fact that the security thread is detectable at the   both visually and on a sorting machine.   Security document according to claims 7 and 8, characterized   in that the security thread is in the form of a complex consisting of at least two wires between which there is at least one   detectable element on sorting machine.   Security document according to one of Claims 8 to 9,   characterized by the fact that the wire comprises at least one element detectable electroconductive.   11 security document according to one of claims 8 to 10,   characterized by the fact that the wire comprises at least one element detectable magnetic.