WO1997038867A1

WO1997038867A1 - Process for producing a printed security core for identity documents, and printed security core

Info

Publication number: WO1997038867A1
Application number: PCT/ES1997/000088
Authority: WO
Inventors: Francisco Cobian Garcia
Original assignee: I.D. Tec, S.L.
Priority date: 1996-04-12
Filing date: 1997-04-11
Publication date: 1997-10-23
Also published as: ES2137805B1; ES2137805A1

Abstract

Process for producing a printed security core for identity documents, for example identity cards, permits, passports and credit cards, as well as the corresponding core. In a first step, a first part (2, 3) of a security print is color printed on a first surface (1') of a base core (1). Then, in a second step, a transparent and translucid binding agent (4), is deposited only on predetermined areas of said surface (1'). In a third step, a second part (2', 3', 5) of said security color print is printed on said surface (1') and on the binding agent (4) deposited on the predetermined areas. The second part (2', 3', 5) is complementary to the first part (2, 3), so that the second part (2', 3', 5) and the first part (2, 3), combined together, form the color security print (2, 2', 3, 3', 5).

Description

Enunciated

Production procedure of a security printed core for identity documents and security printed core.

OBJECT OF THE INVENTION

The invention relates to a method for obtaining a printed security core for identity documents. The process of the present invention is based on partial stratification in several layers or strata of security prints such as guilloche / watermarks. The invention also relates to a corresponding security printed core.

BACKGROUND OF THE INVENTION

The identity documents existing in the market currently have a paper or plastic foil core. In most cases the nucleus is the bearer of both the personal data of the holder of each identity document (filiation data, facial image, signature etc.), as well as security impressions that in the form of guilloche / watermarks in color they are made as protection of said personal data and in order to confer to the document not only an aesthetic and harmonic appearance but also the security that a banknote commonly has.

The covers are usually made of polyester-polyethylene mostly in identity documents with a paper core. In general, counterfeiters attack all types of documents and identity cards trying to fraudulently manipulate their core. Particularly, they try to replace the facial image of their headline originally printed on it, either by any type of printing or by photosensitization if the core is photographic paper. In any case, security prints of guilloche and color watermarks of all current identity documents on the market, are made by printing all the colored lines of said guilloche and precision watermarks on the same single plane or surface of the core.

In many of the paper core identity documents that contain watermarks, luminescent fibrils, etc., the core is comparable to a banknote with the printed personalization of the personal data of the holder thereof. This is also observed in identity documents whose core is photographic paper. All of them have the disadvantage that in fraudulent attempts to separate their layers and delaminate the protective covers by applying heat and chemical reagents, they can separate the printed core with the safety guilloches intact and with personal data also without damage.

Another serious drawback of all identity documents with a paper core, whether photographic or not, lies in the fact that the said paper core can be divided into two parts once the edges of the protective covers of the identity document have been delaminated . This "splitting" effect is possible due to the nature of the paper core that is left on both sides adhered to the respective protective layer or polyester-polyolefin cover with sufficient adhesion to cut / separate the said core in two halves. Once the paper core is separated into two parts, it is possible to proceed to replace the printed or photographic facial image with another by pre-scraping and / or applying very fine drops of sodium hypochlorite as an additional means of removing the paper with said printed image and replacing its hollow by another fraudulent facial image, expressly produced and conveniently treated and digitally retouched and printed on an analogous support with inkjet printer, thermo-sublimation-heat transfer or with electrophotographic printer. DESCRIPTION OF THE INVENTION

The invention relates to a method of producing a printed security core for identity documents, for example identity cards, visas, passports and credit cards, said core having a security print, preferably a color security print. .

In a first step, a first part of said color security print is printed on a first surface; in a second step, transparent and translucent binder is deposited only on predetermined areas of said surface; in a third step, it is printed on said surface, including the preset areas on which binder has been deposited, a second part of said color security print, said second part being complementary to said first part, so that said second part and said first part in combination constitute the security print in color.

The invention also relates to a security printed core for identity documents, said core having a security print, preferably a color security print. According to the invention, a first part of the color security print is printed on a first surface of a base core. A transparent and translucent binder is deposited only on predetermined areas of said surface (and, therefore, on the corresponding parts of the first part of the color security print). A second part of said color security print is printed on said surface, including the pre-set areas on which the binder is deposited. Said second part is complementary to said first part, so that said second part and said first part in combination constitute the security print in color.

The invention also relates to a core obtained by the process of the invention.

That is, by means of the present invention, printing of the security impression (which may comprise color security watermarks / guilloches, etc.) is provided in two differentiated layers on the core, printing part of the security print (for example, lines of the total guilloche / filigree with certain colors) on a surface of the base core of the document, and making a deposit of a transparent and translucent binder only in predetermined areas of one or both sides of the core and then printing the remaining part of the Security print (for example, all remaining lines with their respective specific colors that complete the total guilloche / filigree) over the entire surface even over areas with binder deposit.

With this, it is obtained that in the fraudulent attempts of separation and delamination of the core of the covers or layers of protection, inevitably a destruction of the guilloche of security and personal data especially of the printed facial image, irreversibly so that said core cannot be reused. This destruction or irreversible damage of the customization and security components of the core is caused by the different nature of the binder chosen specifically for each type of core support, whether paper or plastic, which makes heat and reagents commonly used by counterfeiters, such as trichlorethylene, isopropanol, carbon tetracluride, etc., expressly damage the deposited areas with the binder in question. The fact of having introduced a specific stratum corresponding to the areas covered by the binder makes it possible to have a topologically differentiated adhesion in the areas covered by the binder and which have printed part of the lines of the security guilloches. That is, the adhesion between the base core and its cover as well as its behavior against heat and chemical reagents is different at different points of the adhered surfaces, depending on the presence or not of the binder at each point. The behavior is therefore asymmetric of some areas of each face of the core with respect to its response to chemical reagents by applying heat in the aforementioned attempts at delamination and fraudulent separation of the core covers. This asymmetry causes that, as a result of such fraudulent attempts at delamination and separation, core and covers are irreversibly damaged so that they cannot be used to reconstruct a false or manipulated identity document. With the core structure of the present invention the "splitting" effect of separating the paper core in two halves does not occur because, as described above, the assembly does not behave in a homogeneous and symmetrical manner; As a result, part of the damaged core has to be adhered to one of the covers and also irreversibly damaged part adhered to the other cover of the opposite face, when trying to separate the core into two halves.

To confer to the core for identity documents object of the present invention, a greater degree of security against fraudulent manipulations, pigments only visible to ultraviolet light can be added to the mass of the binder used to coat the areas concrete core presets.

Depending on whether the core is applied for one type or another of an identity document, it will be treated with binder deposit and security impressions, a single face of said base core or both sides.

The base core can be paper or plastic.

The preset areas of the base core surface on which binder is deposited have any geometric shape to choose from (for example, straight or curved stripes, logos, shields, legends etc.) but so that they have optimum efficacy in the safety of the core and therefore of the identity document, said preset areas should not cover more than 25% to 30% of the surface of each face of the base core.

The binder that is applied over these areas can be, for example, selected from (I) pure gelatin, (II) a binder that is made up of polyacrylate polymers, (III) a binder that is made of synthetic polyamides, (IV) a polyolefin binder, (V) a composition that includes at least two binders chosen from (I) -

(IV), and (VI) transparent toner for electrophotographic printing. The binder can be deposited with several methods, for example by injection through a mask, by hot micronized injection, by screen printing or even by electrophotographic printing (commonly known as laser printing), with transparent toner which in its mass is they have optionally added pigments only visible to ultraviolet light.

The hot injection tank is made by means of injectors that project the binder mass in a micronized way, that is, in very small micro-drops against the base core support through masks in the form of grooves and windows made of a plastic sheet or aluminum and that have the geometric shape of the coating that is desired to be carried out with the binder.

Micronization in the form of microdroplets is possible because both the gelatin and the other binders mentioned above are hot melt or dilutable. The core can be customized by printing personalization data corresponding to the holder, that is, personal data such as the date of birth or other identification number, signature and facial image. Printing can be done by, for example, printing with a color electrophotographic system or by printing with a thermal transfer-thermo-sublimation printing system. This printing can be done directly on the base core or on the core core with the security impression and binder deposits. On the surface (or surfaces) of the base core with its color security impression and the binder deposited according to the present invention, a thin layer of polyolefin can be heat-bonded. This polyolefin layer can be obtained either by hot pre-laminating a thin sheet / polyolefin film on one or both faces or surfaces of the core, or by hot extrusion of polyolefin on one or both surfaces, thus creating a polyolefin surface. This polyolefin layer serves, among other things, to increase the adhesion of the base core with impressions and binder to thermosetted polyester / polyolefin covers.

The polyolefin layer can be provided with a deposit for certain areas, with a binder with reflective pigments of variable optics, in optional geometric shapes, including straight or curved stripes, logos, legends, shields, figures and letters and combinations thereof. This binder may be the same as the binder that is applied to the base core, or other appropriate binder. If the polyolefin layer is applied by prelaminating a thin sheet or polyolefin film, this sheet or film may have been provided with the binder with the reflective pigments before being applied on the base core.

The core can be customized by printing personalization data (image, signature and / or personal data of the document holder etc.) on the polyolefin surface. This customization can be done by printing with an electrophotographic system on the polyolefin surface.

It is also possible to deposit a transparent binder over specific areas of the polyolefin surface, for example one of the binders (1) - (VI) mentioned above. This is convenient for example, when it is desired to customize the core by using inkjet printers that use water soluble inks or very fluid offset inks, since this ensures that such water soluble inks are absorbed quickly without causing smudges or bleed of inks On the specific areas of the polyolefin surface where said transparent binder has been deposited, the personalization data is printed, for example with a color inkjet printer.

It is also possible to print the personalization data on the base core before printing the first part of the color security printing.

In order to be able to personalize, that is, to transfer the personal data, facial image, signature etc. on the core (with or without polyolefin layer) using the conventional photographic system called inverting transfer by diffusion, several layers of the same are deposited pure gelatin so that each of these areas becomes a photopositive receptor of the photographic images corresponding to said personal data and facial image, taken on a negative photographic support by photosensitization that in a chemical bath with photographic developer are transferred directly by contact and diffusion from the aforementioned negative to the various layers of pure gelatin with which the core areas in question have been coated.

For added security, an additional security print, for example colored lines, can be printed on the polyolefin surface (before and / or after applying the binder), this additional printing serving to reinforce the protection provided by the security print over the core core. One of the possible forms of protection of the base core by applying the method of the present invention is to print directly on the core, certain lines with certain colors of the guilloche / filigree, then deposit by predefined areas of polyolefin or pure gelatin or with polymers, and on this new surface print some other lines of the guilloche / filigree with other colors than the previous ones and then extrude or pre-laminate a polyolefin layer on whose surface in turn the remaining color lines that complete the total security guilloche / watermark are printed.

For added security, a duplicate facial image (of the same size or, for example, of a reduced size compared to the first printed facial image) of the original can be printed in a redundant manner on any part of the core, in inks / toner visible in normal light and / or inks / toner visible in ultraviolet light.

The core of the present application has a stratified structure, that is, the structure has a plurality of surfaces, that is, the surfaces of the base core, the surfaces of the deposited layers of binder, the polyolefin surfaces, etc. To facilitate the authentication of the document and to make its falsification more difficult, a plurality (two, three, ...) superimposed images can be printed, on different surfaces, for example on the base core and on some of the surfaces of the layers of binder. Preferably, these overlapping images are the whole or partial facial images of the wearer; for example, one of the images is a "complete" facial image and another is a partial image, comprising, for example, the silhouette of the face and / or lines corresponding to features such as the nose, eyes etc. One of the images can be printed with inks / toner or similar visible in normal light, and another with ink / toner only visible in ultraviolet light.

That is, a series of superimposed facial images can be printed, on the same or on different faces or layers of the document and on the same or on different surfaces; in this way the possibility of authenticating the document is achieved by checking the coincidence of the images or parts of the images (for example, silhouettes, eyes etc.). The coincidence can be checked, for example, by transparency, by means of a simple ocular inspection (where appropriate, with the help of an ultraviolet light source). One or more of these faces can be printed with ultraviolet tint. Logically, to facilitate authentication by coincidence, the images must be the same size. One of the images may be the "normal" customization image.

On a first facial image visible in normal light or on said duplicate image, it can be printed, with ink / toner only visible in ultraviolet light, a second facial image coinciding exactly on said first facial image printed with visible color inks. The two images can be printed on two different faces of the core or on the same side, so that the superposition of one image with respect to another can be checked for transparency. A possible option is to print with ink / toner visible in ultraviolet light a second image on a first image, on the same side, and additionally print a facial image (for example, with ultraviolet ink / toner) on the other side of the document, coinciding exactly by transparency the silhouette of the three facial images thus printed in three superimposed planes. In order to verify the authenticity of the document based on the coincidence of the different prints (for example, for transparency) they must have the same size and, for example, the same silhouette. Printing is preferably performed with inkjet printing systems or with an electrophotographic system.

With these duplicated prints and, in some embodiments of the invention, superimposed, it becomes extremely difficult to change one facial image to another. The different steps of the present invention can be performed on one or both sides of the core.

Before each process of printing, coating or depositing (for example with binder) and extrusion or prelaminate of polyolefin sheet, an electric corona discharge can be applied on the surface that receives the aforementioned treatment in order to favor affinity and adhesion between elements and components.

Transparent binder deposits can have a thickness of between 5 and 15 microns.

BRIEF DESCRIPTION OF THE FIGURES

An embodiment of the invention will be described below based on the following figures:

Figure 1 is a plan view of the base core after the first step of a preferred embodiment of the process of the present invention is performed. Figure 2 is a plan view of the base core after the second step of a preferred embodiment of the process of the present invention.

Figure 3 is a perspective view of the base core after the third step of a preferred embodiment of the process of the present invention is performed.

Figure 4 illustrates a plan view of the base core after applying a layer of polyolefin and other deposits and prints. Figure 5 illustrates a section of the core according to a preferred embodiment of the present invention.

Figure 6 is a schematic plan view of a preferred embodiment of the invention.

Figure 7 is a schematic perspective view of a preferred embodiment of the invention.

Figure 8 is a schematic perspective view of another preferred embodiment of the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF

THE INVENTION Figure 1 illustrates the base core after a first step of the process, in which a first part (2,3) of a color security print has been printed, on a first surface (Y) of a base core (one ). The first part of the security print includes watermarks / guilloches (2) in color and letters (3). Figure 2 shows how the base core (1), after a second step of the process, has received transparent and translucent binder deposits (4) only on predetermined areas of said surface (1 '). The binder can be deposited by, for example, hot micronized injection, screen printing or electrophotographic printing.

Figure 3 illustrates how, after a third step, the base core has been provided with a second part (2 ', 3', 5) of the security impression, printed on the surface (1 ') of the base core and on binder deposits (4). Apart from watermarks / guilloches (2 ', 3'), the second part of the security print includes a shield (5). The - 77 - second part (2 ', 3', 5) of said color security printing is complementary to the first part (2,3), so that said second part (2 ', 3', 5) and said First part (2,3) in combination constitutes the security print in color (2,2 ', 3,3', 5) that can be seen in Figures 1-3. The base core (1) can be made of paper or plastic, and the binder (4) can be one of the binders (1) - (VI) mentioned in the description of the invention. In addition, the binder (4) may contain in its mass pigments only visible in ultraviolet light.

As can be seen in Figure 4, in a preferred embodiment of the invention a layer (6) of polyolefin has been applied, based on hot extruding a thin layer or hot pre-laminating a thin polyolefin film, thus obtaining a surface ( 7) polyolefin. On this surface, geometric shapes such as straight or curved stripes, logos and / or legends of transparent binder (9) can be deposited with the addition of color reflective pigments (9 ') dispersed / emulsified in the mass of said binder (9). The binder (9) may be one of the specific binders (1) - (VI) mentioned above, or another type of binder.

For added security, an additional security design, for example color guilloches / watermarks (8), can be printed on the polyolefin surface (7).

According to the preferred embodiment illustrated in Figure 4, a transparent binder (13) is deposited, which can be one of the aforementioned binders (1) - (VI), on certain areas of the polyolefin surface (7). On this binder, personalization data, for example personal data (10), signature (11) and / or facial image (12) of an identity document holder can be printed, for example. This data can be printed with a color inkjet printer. Figure 5 reflects a section of the core according to an embodiment of the present invention. On the first surface (V) of the base core (1) a transparent binder (4) has been deposited first and then the assembly has been covered with a layer (6) extruded or hot pre-laminated of polyolefin, obtaining a surface of polyolefin (7) on which a binder (9) has been deposited with reflective pigments (9 ') and other transparent binder (13). Corresponding layers have been deposited on a second surface (1 ") of the base core (1) and, in addition, several superimposed layers (13 ', 13") of gelatin, to convert the corresponding zone into a photopositive receptor of a photographic system of inverting transfer by diffusion.

Figure 6 schematically reflects a preferred embodiment of the following application, where on some of the different layers (paper, plastic, binder, polyolefin ...) of the core (17) personalization data has been printed as personal data (10 ), signature (11) and / or facial image (12) of the document holder. In addition to the first facial image (12), a duplicate facial image (14) of the original has also been printed redundantly on any part of the core. This printing may have been made with inks / toners chosen from inks / toners visible to light, including ultraviolet light. The duplicated facial image (14) is of a reduced size compared to the first facial image (12).

Figure 7 shows another embodiment of the present invention, in which, in the core (17) according to the invention, apart from the first facial image (12) a second image has been printed with ink / toner only visible in ultraviolet light facial (15) coinciding exactly on a first facial image (12) printed with color inks / toner visible on a first front face of the nucleus. On the other side of the core, a third facial image (16) has been printed with ink / toner only visible in ultraviolet light, the silhouette of the three facial images thus printed on three superimposed planes coinciding exactly with transparency.

Figure 8 schematically illustrates a core of the present invention (17), in which with a thi / a toner only visible in ultraviolet light, a second facial inrin (15) has been printed on a first front face of the nucleus and a third facial imag (16) on a second posterior face of the nucleus, the silhouettes of said two facial images (15,16) printed with inks / toner only visible in ultraviolet light coinciding by transparency. In addition, Figure 8 illustrates the first printed facial image (11).

Claims

1.- Production procedure of a printed security core for identity documents, for example identity cards, visas, passports and credit cards, said core having a color security print (2,2 ', 3,3 ', 5), characterized in that in a first step, a first part (2,3) of said color security print is printed on a first surface (Y) of a base core (1); in a second step, transparent and translucent binder (4) is deposited only on predetermined areas of said surface (V); in a third step, it is printed on said surface (Y) and on the binder (4) in the predetermined areas on which binder (4) has been deposited, a second part (2 ', 3', 5) of said printing security in color, said second part (2 ', 3', 5) being complementary to said first part (2,3), such that said second part (2 ', 3', 5) and said first part (2 , 3) in combination they constitute the security print in color (2,2 ', 3,3', 5).

2. Method according to the preceding claim, wherein the color security print (2.2 ', 3.3', 5) includes watermarks / guilloches (2.2 ') in color.

3. Method according to any of claims 1-2, wherein the base core (1) is paper.

4. Method according to any of claims 1-2, wherein the base core (1) is a plastic sheet.

5. Method according to any of the preceding claims, wherein the binder (4) is

(I) pure jelly.

6. Method according to any of claims 1-4, wherein the binder (4) is (II) a binder that consists of polyacrylate polymers.

7. Method according to any of claims 1-4, wherein the binder (4) is

(III) a binder that is made of synthetic polyamides.

8. Method according to any of claims 1-4, wherein the binder (4) is

(IV) a polyolefin binder.

9. Method according to any of claims 1-4, wherein the binder (4) is (V) a composition that includes at least two binders chosen from (I) pure gelatin, (II) a binder that is constituted by polyacrylate polymers, (III) a binder consisting of synthetic polyamides, (IV) a polyolefin binder.

10. Method according to any of claims 1-4, wherein the binder (4) is

(VI) transparent toner for electrophotographic printing.

1 1. Method according to any of claims 1-9, wherein the binder (4) contains in its mass pigments only visible in ultraviolet light.

12. Method according to any of claims 1 -1 1, wherein the binder (4) is deposited by hot micronized injection.

13. Method according to any of claims 1-1 1, wherein the binder (4) is deposited by screen printing or electrophotographic printing.

14. Method according to any of the preceding claims, which - 75 - comprises a fourth step, on which on the surface (V) on which the security print in color (2,2 ', 3,3', 5) has been printed, a polyolefin layer ( 6) by hot pre-lamination of a thin polyolefin film, obtaining a polyolefin surface

(7).

15. Method according to any of claims 1-13, comprising a fourth step in which on the surface (1 ') on which the security print in color (2,2', 3,3 'has been printed) , 5), a polyolefin layer (6) is applied by hot extrusion of polyolefin, obtaining a polyolefin surface (7).

16. Method according to claim 14 or claim 15, wherein on the polyolefin surface (7), certain additional safety color lines (8) are printed in a fifth step.

17. Method according to claim 14 or claim 15, wherein on the surface of polyolefin (7), geometric shapes are deposited in a fifth step, for example straight or curved stripes, logos and / or legends, of transparent binder (9) with the addition of color reflective pigments (9 ') dispersed / emulsified in the mass of said binder (9).

18. Method according to claim 17, wherein the transparent binder (9) with the addition of color reflective pigments (9 ') that is deposited on the surface of polyolefin (7) is a binder selected from (I) pure gelatin , (II) a binder that is composed of polyacrylate polymers, (III) a binder that is made of synthetic polyamides, (IV) a polyolefin binder, (V) a composition that includes at least two binders chosen from (l) - (IV), and (VI) transparent toner for electrophotographic printing.

19. Method according to any of the preceding claims, which It includes the additional personalization step by printing personalization data, for example personal data (10), signature (11) and / or facial image (12) of an identity document holder.

20. Method according to claim 19, wherein personalization is carried out with printing of personal data (10), signature (11) and / or facial image (12) of the holder of the identity document by printing with heat transfer printing system -Thermosublimation in color or by printing with color electrophotographic system.

10

21. Method according to claim 19, in which the personalization is carried out with printing of personal data (10), signature (11) and / or facial image (12) of the holder of the identity document by printing with an electrophotographic system on the polyolefin surface

75 (7).

22. Method according to claim 14 or claim 15, comprising the additional step of depositing a transparent binder (13) onto specific areas of the polyolefin surface (7).

twenty

23. Method according to claim 22, wherein said transparent binder (13) is a binder selected from (I) pure gelatin, (II) a binder that is constituted by polyacrylate polymers, (III) a binder that is constituted by synthetic polyamides, (IV) a polyolefin binder, (V) a composition that includes at least two binders chosen from (l) - (IV), and (VI) transparent toner for electrophotographic printing.

24. Method according to any of claims 22 and 23, in which on the specific areas of the polyolefin surface (7) where said transparent binder (13) has been deposited, printing with inkjet printer is performed color, personalization data such as personal data (10), signature (11) and / or facial image (12) of an identity document holder.

35

25. Method according to any of claims 19-24, wherein a duplicated facial image (14) of the original is printed in a further step redundantly on any part of the core, in inks / toners chosen between inks / toner visible to light, including ultraviolet light.

26.- Method according to any of claims 19-25, wherein with ink / toner only visible in ultraviolet light, a second facial image (15) is printed exactly coinciding with a first facial image (12) printed with colored inks visible on a first front face of the core and a third facial image (16) with ink / toner only visible in ultraviolet light is also printed on a second rear face of the core, exactly matching the silhouette of the three facial images thus printed by transparency in three overlapping planes.

27.- Method according to any of claims 19-25, wherein with ink / toner only visible in ultraviolet light, a second facial image (15) is printed on a first front face of the core and a third facial image (16 ) on a second rear face of the core, the silhouettes of said two facial images (15,16) printed with inks / toner only visible in ultraviolet light coinciding by transparency.

28. A method according to any of claims 14 or 15, in which, on specific areas of the polyolefin surface (7), gelatin emulsion is deposited in superimposed layers (13 ', 13 "), each of said specific zones becoming in a photopositive receiver of a photographic system of inverting transfer by diffusion.

29. The method according to any of the preceding claims, wherein the method is subjected to a second surface (1 ") of the base core (1) to the first, second and third steps and, optionally, to other steps defined in the preceding claims. .

30.- Procedure according to any of the preceding claims, in which on certain surfaces of the core, selected from, for example, the first surface (1 ', 1 ") of the base core, binder deposit surfaces (4.9', 13) and polyolefin surfaces (7), are printed on minus two facial images (12,15,16) complete or partial so that said images are mutually overlapping.

31. A method according to claim 30, wherein at least one of said superimposed images is printed with ink / toner only visible in ultraviolet light.

32.- Method according to claim 1, wherein personalization data are printed on the base core (1), for example personal data (10), the signature (11) and / or the facial image (12) of a holder of the identity document, before printing the first part (2,3) of said security print in color (2,2 ', 3,3', 5).

33.- Printed security core for identity documents, for example identity cards, visas, passports and credit cards, said core having a security print in color (2.2 \ 3.3 \ 5), characterized in that it includes a first part (2,3) of the color security print, printed directly on a first surface (V) of a base core (1); a transparent and translucent binder deposit (4) only on predetermined areas of said surface (V) and on corresponding parts of said first part (2,3) of the color security print; and a second part (2 ', 3', 5) of said security print in color printed on said surface (1 ') and on the binder (4) in the predetermined areas on which the binder (4) is deposited, being said second part (2 ', 3', 5) complementary to said first part (2,3), such that said second part (2 ', 3', 5) and said first part (2,3) in combination constitute Color security printing (2,2 ', 3,3', 5).

34.- Printed security core for identity documents, for example identity cards, visas, passports and credit cards, said core having a color security print (2,2 ', 3,3', 5), characterized in that the core is produced by the method according to any of claims 1-32.

35.- Core according to any of claims 33-34, wherein the color security print (2.2 ', 3.3', 5) includes watermarks / guilloches (2.2 ') in color.

36.- Core according to any of claims 33-35, including a layer (6) of polyolefin adhered on the first surface (V) of the base core (1) and on the binder deposits (4) and, optionally, deposits of binder (13) deposited on a surface (7) of said polyolefin layer (6).

37.- Core according to any of claims 33-36, which has a plurality of surfaces, having a plurality of whole or partial facial images printed on said surfaces, mutually superimposed (12,15,16).

38.- Core according to claim 37, wherein at least one of said superimposed images is printed with ink / toner only visible in ultraviolet light.