CN114905880B

CN114905880B - Security element for embedding in security documents

Info

Publication number: CN114905880B
Application number: CN202210117649.6A
Authority: CN
Inventors: T.博登迪克
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient GmbH
Priority date: 2021-02-08
Filing date: 2022-02-08
Publication date: 2024-10-01
Anticipated expiration: 2042-02-08
Also published as: CN114905880A; EP4039494B1; EP4039494A1; DE102021000626A1

Abstract

The invention relates to a security element (20) for embedding in a paper-based security document (10), comprising a carrier matrix with alphanumeric and/or graphic usage instructions (26), characterized in that the carrier matrix has, in addition to the usage instructions (26), tamper instructions (28) which are imprinted with a camouflage pattern (30) that is soluble in organic solvents and are masked in this way.

Description

Security element for embedding in security documents

Technical Field

The invention relates to a security element for embedding in a paper-based security document, wherein the security element has a carrier matrix with alphanumeric and/or graphic instructions for use.

Background

To prevent tampering by organic solvent erasure, security papers are often equipped with chemical security systems that make tampering visible by color reactions. Potential counterfeiters now know that this color reaction is initiated in the case of organic solvents by various pigment particles which are insoluble in water but soluble by the solvent. Upon erasure with an organic solvent, the small pigment particles are depleted and produce a stain as a tamper indication.

However, many pigment particles can be completely dissolved by soaking the security paper in a solvent bath so that the color disappears by dilution. Most security printing pigments and security features survive such soaking due to their high resistance, and there is a risk that chemical security will be overcome by soaking the security paper.

Disclosure of Invention

The object of the invention is to effectively protect paper-based security documents against tampering or to make tampering easily identifiable.

The present invention provides a better security element for embedding in a paper-based security document. The security element comprises a carrier matrix with alphanumeric and/or graphical indications of use. In addition to the usage indication, the carrier matrix also has tamper indications, which are printed with camouflage patterns (Tarnaufdruck or called camouflage print patterns, encryption prints) dissolved in the organic solvent and are thereby masked (or hidden).

The camouflage pattern is suitably dissolved in an organic solvent and thereby reveals the tamper indication. Organic solvents frequently used by counterfeiters are, for example, polar solvents, such as alcohols, or nonpolar solvents, such as carbon tetrachloride.

The tamper indication is advantageously applied to the carrier substrate a plurality of times, in particular alternating with alphanumeric and/or graphical indications of use.

Preferably, the tamper indication is formed by a pattern, character or code, in particular an alphanumeric string (in the shade or in the sun). Tamper indications may be constituted, for example, by "invalid", "false" or other words that indicate tampering that has occurred.

The camouflage pattern may be formed by a uniform printed surface covering the tamper indication. However, according to an advantageous embodiment, the camouflage pattern can also be formed by a pattern, character or code, in particular as a negative or positive text, in which case it can in particular form the usage information. Upon attempted tampering with an organic solvent, the camouflage pattern and the usage information formed therefrom are dissolved, and additional information indicative of tampering is present at the location by tamper indication. Of course, tamper indication is different from usage information.

It is advantageous that the tamper indication is configured to be resistant to solvents. Advantageously, the usage indication is also constructed to be resistant to solvents, contrary to the mentioned usage information, which is formed by camouflage patterns if necessary. However, the usage information of the camouflage pattern may present the same information as the usage indication, or may be related to the usage indication, or the usage indication may be supplemented to form overall information.

The carrier matrix of the security element preferably comprises a plastic film, in particular made of polyethylene terephthalate (PET).

In order to further increase the security against forgery, at least one printing pigment that absorbs electromagnetic radiation in the infrared wavelength range (hereinafter infrared-absorbing printing pigment) and at least one printing pigment that transmits electromagnetic radiation in the infrared wavelength range (hereinafter infrared-transmitting printing pigment) may be applied to the carrier substrate of the security element. The authenticity of a security document, such as a passport paper, can thus be additionally verified by checking the printed pigment under infrared irradiation. Such security features are hidden security features, so-called "Level 2" features or hidden features.

In an advantageous embodiment, the camouflage pattern correspondingly contains at least one printed pigment which absorbs electromagnetic radiation in the infrared wavelength range and has a first diffuse reflection value (Remissionswert), and the tamper indication and/or the one or more usage indications contain at least one printed pigment which transmits electromagnetic radiation in the infrared wavelength range and has a second diffuse reflection value. The difference between the first and the second diffuse reflection value is advantageously at least 40% here.

Alternatively, the tamper indication may comprise an infrared absorbing printed pigment. Optionally, additionally, the one or more usage instructions may also include an infrared absorbing printing pigment.

Advantageously, both the camouflage pattern and the tamper indication are formed by a pattern, character or code, in particular an alphanumeric character string. The tamper indication is preferably formed by a pattern, character or code which consists of only a part of the pattern, character or code of the camouflage pattern, for example of all second characters or every other character of the camouflage pattern or of only the unique character of the camouflage pattern. Thus providing an explicit indication of the tampering that occurred. The pattern, character or code component of the tamper indication is advantageously arranged to exactly match the corresponding pattern, character or code component of the camouflage pattern, such that the tamper indication is obscured by the camouflage pattern.

The at least one infrared absorbing printed pigment of the camouflage pattern and the at least one infrared transmitting printed pigment of the use indicator advantageously have the same hue when irradiated with visible electromagnetic radiation. I.e. if the text, character or pattern consists of two printing pigments which have the same hue but different infrared transmission when irradiated with visible electromagnetic radiation, it is presumed that the printed image is produced with the only printing pigment when viewed with visible electromagnetic radiation. However, upon irradiation with electromagnetic radiation in the infrared wavelength range, the viewer can recognize that the portions of the printed image are applied with infrared-transmissive printing pigments.

The wavelength of electromagnetic radiation in the infrared wavelength range of the printing pigments for infrared transmission and infrared absorption to be examined is particularly preferably in the range from 700nm to 1000 nm. The at least one infrared-absorbing printing pigment advantageously has a first diffuse reflectance value of <50% and the at least one infrared-transmitting printing pigment has a second diffuse reflectance value of > 90%.

The at least one infrared-transmissive printing pigment and the at least one infrared-absorbing printing pigment are particularly preferably formed by solvent-based, water-based or ultraviolet-curable printing pigments or inks which are printed onto the carrier substrate of the security element by gravure printing, digital printing, ultraviolet offset printing, screen printing, jet printing or offset printing.

Infrared absorbing and infrared transmitting printing pigments are usually printed with an intermediate dry, exact match in two processes. Preferably, the camouflage pattern is applied as a final printing process. In this case, different printing pigment systems are used depending on the substrate to be printed. Print pigments that appear transparent when irradiated with electromagnetic radiation in the infrared wavelength range are typically pigmented colors, whereas infrared absorbing print pigments are typically pigment particle-based print pigments.

The authenticity of the security element can be checked on the basis of an infrared sensor or an infrared checking device, such as an infrared camera, i.e. when irradiated with electromagnetic radiation in the infrared wavelength range, for example between 850nm and 940nm, only the infrared absorbing printing element is visible, not the infrared transmitting printing element. In contrast, all printing elements of infrared transmitting and infrared absorbing printing pigments are visible when irradiated with visible electromagnetic radiation or light having a wavelength of about 380nm to about 750 nm. Therefore, the infrared transmittance functions as a hidden feature (english: hidden feature).

The security element is in particular a security thread or a security tape. For example, security threads for passport papers are produced in the prior art as so-called country code threads, with national flags and negative or positive applied in intaglio printing, uv offset printing or digital printing on plastic substrates, for example substrates made of PET.

The invention also includes a paper-based security document with an at least partially embedded security element of the type described above. In this case, it is advantageous if the security element is completely embedded in the security document. However, the security element may also be embedded only partially in the security document and exposed in the window area of one or both of the opposing surfaces of the security document.

When the security document is immersed in an organic solvent, the camouflage pattern is suitably dissolved and thereby reveals a tamper indication of the embedded security element.

An advantage of a security element at least partially embedded in a paper-based security document is that the camouflage pattern in the embedded security element that is removed by the counterfeiter with solvent treatment is not easily added anymore.

The at least partially embedded security element is preferably a security thread.

Paper-based security documents are in particular documents, passports, passport pages or value documents, such as banknotes, stocks, bonds, certificates, vouchers, checks or high-value tickets.

Drawings

Other embodiments and advantages of the invention are set forth below with reference to the drawings, in which scale bars and proportions are not shown, in order to improve readability. These examples should not be construed as limiting. For example, descriptions of embodiments having multiple elements or components should not be construed as necessary for implementation of all such elements or components. Conversely, other embodiments may include alternative elements and components, fewer elements or components, or additional elements or components. Elements or components of different embodiments may be combined with each other unless otherwise specified. Modifications and variations described with respect to one of the embodiments may also be used with other embodiments. To avoid repetition, identical or corresponding elements in different figures are designated with identical reference numerals and are not explained repeatedly.

In the drawings:

Figure 1 shows a schematic view of a passport sheet with a security thread fully embedded in the paper,

FIG. 2 shows a schematic view of a security thread according to one embodiment of the invention, wherein (a) shows that the thread has a perfect camouflage pattern in an initial state; (b) The line is shown after an attempt to tamper, the camouflage pattern dissolves,

FIG. 3 shows a schematic view of a security thread according to another embodiment of the present invention, wherein (a) shows that the thread has a perfect camouflage pattern in an initial state; (b) The line is shown after an attempt to tamper, the camouflage pattern dissolves,

Fig. 4 shows a security thread according to another embodiment of the present invention, in which (a) shows a thread having an intact camouflage pattern in an initial state when irradiated with visible electromagnetic radiation, (b) shows a thread in an initial state when irradiated with electromagnetic radiation in the infrared wavelength range, (c) shows a thread in which the camouflage pattern dissolves after tampering is attempted when irradiated with visible electromagnetic radiation, and (d) shows a thread after tampering is attempted when irradiated with electromagnetic radiation in the infrared wavelength range.

Detailed Description

The invention will now be described by way of example with respect to a security thread for passport paper or document paper. Fig. 1 is a schematic diagram of a passport sheet 10 of a passport book, which is not shown per se. The passport sheet 10 is provided with a security thread 20 fully embedded in the paper of the passport sheet 10 for security purposes.

For illustration, two variants of security thread according to the invention which can be used for embedding in a passport page 10 are shown in more detail in fig. 2 and 3. Referring first to fig. 2 (a), a security thread 20 has a carrier substrate, such as a plastic film made of polyethylene terephthalate (PET), on which a usage area 22 and a tamper display area 24 are alternately arranged.

In the embodiment of fig. 2, the usage area 22 contains a graphical usage indication, such as a colored pattern 26 of a national flag of the passport booklet.

In the tamper display area 24, a tamper indication 28 is printed on the carrier film, which in this embodiment is configured in the form of a word "VOID" (fig. 2 (b)). Tamper indication 28 is respectively imprinted (or overprinted) with a camouflage pattern 30 that is soluble in an organic solvent such that tamper indication 28 is masked (or hidden) under normal conditions as shown in fig. 2 (a).

If the passport sheet 10 is immersed in an organic solvent during tampering, the camouflage pattern 30 is dissolved by the solvent and thereby reveals the tamper indication 28, as shown in fig. 2 (b). The usage indication 26 and tamper indication 28 themselves are printed in a color that is resistant to the solvent and does not change when the passport sheet is immersed in the solvent. Tampering may be made apparent by the exposed tamper indication 28 such that the tampered line of fig. 2 (b) cannot be used to recreate the passport page 10. The passport sheet 10 can thus be efficiently protected from tampering by soaking by the combined "paper + security thread".

Fig. 3 shows a security thread 20 according to a further embodiment of the invention, wherein the application areas 22 and the tamper-evident areas 24 are likewise arranged alternately on the carrier matrix. In this embodiment, the area of use contains an alphanumeric pattern 32, for example in the form of the name of the country in which the passport booklet is issued, in addition to the colored pattern 26 of the national flag.

As in the design of fig. 2, tamper indication 28 is printed in tamper display area 24 (fig. 3 (b)). Tamper indication 28 is respectively imprinted with a camouflage pattern 30 that is soluble in an organic solvent such that tamper indication 28 is masked in the normal case shown in fig. 3 (a).

By immersing the passport sheet 10 in an organic solvent, the camouflage pattern 30 is dissolved by the solvent and thereby reveals the tamper indication 28, as shown in fig. 3 (b). The usage indication 26, 32 and tamper indication 28 are themselves in a color pattern that is resistant to solvents and does not change when the passport sheet is immersed in solvents. Tamper is also made obvious here by the tamper indication 28 being exposed so that the tampered line of fig. 3 (b) cannot be used to recreate the passport page 10.

In fig. 2 and 3, the camouflage pattern 30 is formed of a uniform printed surface, respectively. However, the camouflage pattern may be formed in the form of a pattern, character or code and the usage information is formed in the initial state of fig. 2 (a) or fig. 2 (b). When the passport sheet is soaked, the usage information disappears and instead the tamper indication 28 appears as the camouflage pattern dissolves.

Thus, according to a design not shown, the usage area 22 may contain, for example, a color pattern in the form of the word "LAND", which in the tamper display area 24 complements the overall information "DEUTSCHLAND" by a camouflage pattern structured in the form of the word "DEUTSCH".

Upon tampering with an organic solvent, the camouflage pattern formed by the letter "DEUTSCH" is dissolved by the solvent and the tamper indication in the tamper display area 24 is thereby revealed, in this design the tamper indication is formed by the letter sequence "XXX", for example. The use indication and tamper indication are printed in a color that is resistant to the solvent and does not change when immersed in the solvent. Tamper is made apparent by the tamper indication being exposed.

Fig. 4 shows a security thread 40 according to a further embodiment of the invention, wherein the application area 22 and the tamper-evident area 24 are likewise arranged alternately on the carrier substrate. In this embodiment, the area of use contains, in addition to the colored pattern 26 of the national flag, an alphanumeric pattern 32, for example in the form of the typeface "PASSPORT" (for example, in conjunction with the typeface which is mirror-symmetrical in the defined area for viewing from the backside).

As in the design of fig. 3, tamper indication 28 (fig. 4 (c)) is patterned in tamper-evident area 24, here in the form of an incomplete or defective name of the country from which the passport is issued. Tamper indication 28 is printed with a camouflage pattern 30, respectively, that is soluble in organic solvents, in the form of the (complete) name of the country where the passport is issued, so that tamper indication 28 is masked in the normal case shown in fig. 4 (a), 4 (b).

In contrast to the embodiment shown in fig. 3, the pattern here comprises at least one printing pigment that absorbs in the infrared wavelength range of electromagnetic radiation and at least one printing pigment that transmits in the infrared wavelength range of electromagnetic radiation. In the illustrated embodiment, camouflage pattern 30 is printed with an infrared absorbing printed pigment, alphanumeric pattern 32 is printed with an infrared transmissive printed pigment, pattern 26 is printed with a plurality of printed pigments, and tamper indication 28 is printed with an infrared transmissive printed pigment onto the carrier substrate. The infrared-absorbing printed pigment of the camouflage pattern 30 and the infrared-transmitting printed pigment of the pattern 32 can be selected here such that they have the same hue when irradiated with visible electromagnetic radiation.

Upon irradiation with visible electromagnetic radiation or light having a wavelength in the range of about 380nm to about 750nm, the observer can recognize both the camouflage pattern 30 in the tamper display area 24 and the patterns 26, 32 in the usage area 22 (fig. 4 (a)). On the contrary, when irradiated with electromagnetic radiation in the infrared wavelength range, for example radiation of the wavelength of 850nm, the infrared-transmitting printing element is not identifiable. Thus, the observer perceives only the camouflage pattern 30 ("Country") and the pattern 26 in the form of a national flag (fig. 4 (b)).

When tampered with an organic solvent, the camouflage pattern 30 and the usage information "Country" formed therefrom are dissolved by the solvent, whereby the tamper indication 28 in the tamper display area 24 is exposed, the tamper indication 28 being formed in the present design by the letter "o" (as part of the name of the Country where the passport is issued).

The use indication 26, 32 and tamper indication 28 are printed in a color that is resistant to the solvent and does not change when immersed in the solvent. When irradiated with visible electromagnetic radiation or light having a wavelength in the range of about 380nm to about 750nm, the image shown in fig. 4 (c) is thus formed. An infrared transmissive printing element is invisible when irradiated with electromagnetic radiation in the infrared wavelength range.

Thus, the observer perceives only the pattern 26 in the form of a national flag (fig. 4 (d)).

In a design of tamper indication 28, not shown here, it may contain infrared absorbing printing pigments instead of infrared transmitting printing pigments. In this case, the tamper indication is also visible when irradiated with electromagnetic radiation in the infrared wavelength range, so that the observer sees tamper indication 28 in addition to pattern 26 in the form of a national flag.

List of reference numerals:

10 passport pages

20 Anti-fake line

22 Area of use

24 Tamper display area

26 Pattern of graphics

28 Tamper indication

30 Camouflage pattern

32 Alphanumeric pattern

40 Anti-fake line

Claims

1. A security element for embedding in a paper-based security document, the security element having a carrier matrix with alphanumeric and/or graphic usage indications, characterized in that the carrier matrix has, in addition to the usage indications, tamper indications which are imprinted with and masked by means of a camouflage pattern dissolved in an organic solvent, wherein the camouflage pattern contains at least one printed pigment absorbing electromagnetic radiation in the infrared wavelength range having a first diffuse reflection value, and the tamper indication and/or the usage indication or indications contains at least one printed pigment transmitting electromagnetic radiation in the infrared wavelength range having a second diffuse reflection value.

2. A security element according to claim 1, wherein said camouflage pattern is dissolved in an organic solvent and thereby reveals said tamper indication.

3. A security element according to claim 1 or 2, wherein the tamper indication is applied to the carrier substrate a plurality of times alternating with alphanumeric and/or graphical use indications.

4. A security element according to claim 1, wherein the tamper indication is formed by a pattern, character or code.

5. A security element according to claim 1, wherein the camouflage pattern is formed by a pattern, character or code, wherein the camouflage pattern forms a different usage information than the tamper indication.

6. A security element according to claim 1, wherein said tamper indication is designed to be resistant to solvents.

7. A security element according to claim 1, wherein said use indicator is designed to be resistant to solvents.

8. A security element according to claim 1, wherein the carrier matrix comprises a plastic film.

9. A security element according to claim 1, wherein the difference between the first and second diffuse reflectance values is at least 40%.

10. A security element according to claim 9, wherein at least one infrared absorbing printed pigment of the camouflage pattern and at least one infrared transmitting printed pigment of the use indicator have the same hue when irradiated with visible electromagnetic radiation.

11. A security element according to claim 1, wherein not only the camouflage pattern but also the tamper indication is formed by a pattern, character or code.

12. A security element according to claim 11, wherein the pattern, character or code component of the tamper indication is arranged to exactly match the corresponding pattern, character or code component of the camouflage pattern such that the tamper indication is obscured by the camouflage pattern.

13. A security element according to claim 1, wherein the security element is a security thread or a security band.

14. A security element according to claim 1, wherein said tamper indication is formed by an alphanumeric string.

15. A security element according to claim 11, wherein the tamper indication is formed by a pattern, character or code, the pattern, character or code being constituted by only a portion of the pattern, character or code of the camouflage pattern.

16. A paper-based security document with an at least partially embedded security element according to any one of claims 1 to 15.

17. The paper-based security document of claim 16, wherein the security element is fully embedded in the security document.

18. A paper-based security document according to claim 16 or 17, wherein the camouflage pattern dissolves and thereby reveals a tamper indication of the embedded security element when the security document is immersed in an organic solvent.

19. The paper-based security document according to claim 16, wherein the at least partially embedded security element is a security thread.

20. The paper-based security document according to claim 16, wherein the paper-based security document is a document, passport or value, and the value is a banknote, stock, bond, certificate, voucher, check or high value ticket.