EP4145426A1 - Security label - Google Patents

Abstract

Comprising a security label (1) with multiple layers
- a laser-writable layer (2) with black aluminum oxide, the laser-writable layer (2) having an upper side (4) and an underside (5) which are arranged opposite one another and point away from one another,
- at least one transparent protective layer (3), which is arranged in front of the laser-writable layer (2) as seen in a first direction (6) in order to protect the laser-writable layer (2) from external influences, the first direction (6) being dependent on the Top (4) to the bottom (5) has, as well as
- A contrast layer (7) which is arranged behind the laser-writable layer (2) as seen in the first direction (6). According to the invention, at least one of the multiple layers is designed as a fracture layer (8) made of a brittle plastic film in order to prevent destruction of the at least one fracture layer (8) and the laser-writable layer (2), and optionally one or more layers lying in between, in the case of a To cause manipulation or detachment of the security label (1) glued to a substrate (9).

Description

FIELD OF THE INVENTION

• eine laserbeschreibbare Schicht mit schwarzem Aluminiumoxid, wobei die laserbeschreibbare Schicht eine Oberseite und eine Unterseite aufweist, die einander gegenüberliegend angeordnet sind und voneinander weg weisen,
• mindestens eine transparente Schutzschicht, die in einer ersten Richtung gesehen vor der laserbeschreibbaren Schicht angeordnet ist, um die laserbeschreibbare Schicht vor äußeren Einflüssen zu schützen, wobei die erste Richtung von der Oberseite zur Unterseite weist, sowie
• eine Kontrastschicht, die in der ersten Richtung gesehen hinter der laserbeschreibbaren Schicht angeordnet ist.

The present invention relates to a security label comprising multiple layers

• a laser writable layer with black aluminum oxide, the laser writable layer having a top and a bottom which are arranged opposite to one another and point away from one another,
• at least one transparent protective layer, which is arranged in front of the laser-writable layer as seen in a first direction in order to protect the laser-writable layer from external influences, the first direction pointing from top to bottom, and
• a contrast layer positioned behind the laser writable layer as viewed in the first direction.

STATE OF THE ART

Security labels for identifying goods are known per se and are used in the most varied of fields of technology. For example, components supplied in the automotive industry are provided with such security labels.

In order to be able to efficiently write desired information on these security labels, it is with security labels known to provide a laser writable layer. Black aluminum oxide, which has a black metallic color due to a substoichiometric oxygen content of the aluminum oxide, is particularly suitable for such a layer. In the following, “laser-writable layer” is to be understood as meaning such a black aluminum oxide layer (sometimes also referred to as “black metallization”), unless otherwise stated. A particularly efficient production of films that have such a black aluminum oxide layer is from EP 1522606 B1 known.

Corresponding layers can be "written on" by the action of a laser, with the resulting energy input making the aluminum oxide layer transparent along the track of the laser beam. The processes responsible for this, which take place due to the energy input, can include evaporation, oxidation, ablation and the like, such as from the US5766827A is known. In order to make the track or the writing particularly visible, an opaque, optically contrasting layer can be arranged below the aluminum oxide layer.

A most desirable property of security labels is the so-called document authenticity, which includes in particular the property that manipulation or even removal of the security label is not possible without leaving traces. In this context, for example, so-called “void labels” are known from the prior art, which are used to indicate attempts to manipulate objects and packaging, cf EP 2603910 B1 or the EP 2603911 B1 . With these void labels, a layer structure with at least one separating lacquer layer ensures that a security feature that was previously invisible or in the affixed state appears on the label surface as soon as the void label is detached from the respective substrate. With the security feature it is mostly in the form of lettering, images, patterns or the like. However, it has been shown that a reliably functioning “laser-writable security label”, ie a security label with a laser-writable layer, cannot be produced simply by combining or by simply additionally producing a laser-writable layer with or for such a void label. During the application or production of the laser-writable layer, too much energy is typically introduced into the existing layer system of the void label, so that the existing layer system of the void label no longer functions reliably and document authenticity is not guaranteed.

OBJECT OF THE INVENTION

It is therefore the object of the present invention to provide a laser-writable security label which overcomes the disadvantages outlined above and ensures document authenticity.

PRESENTATION OF THE INVENTION

• eine laserbeschreibbare Schicht mit schwarzem Aluminiumoxid, wobei die laserbeschreibbare Schicht eine Oberseite und eine Unterseite aufweist, die einander gegenüberliegend angeordnet sind und voneinander weg weisen,
• mindestens eine transparente Schutzschicht, die in einer ersten Richtung gesehen vor der laserbeschreibbaren Schicht angeordnet ist, um die laserbeschreibbare Schicht vor äußeren Einflüssen zu schützen, wobei die erste Richtung von der Oberseite zur Unterseite weist, sowie
• eine Kontrastschicht, die in der ersten Richtung gesehen hinter der laserbeschreibbaren Schicht angeordnet ist, erfindungsgemäß vorgesehen, dass zumindest eine der mehreren Schichten als Bruchschicht aus einer spröden Kunststofffolie ausgebildet ist, um eine Zerstörung der zumindest einen Bruchschicht sowie der laserbeschreibbaren Schicht, und gegebenenfalls einer oder mehrerer dazwischenliegender Schichten, bei einer Manipulation oder einem Ablösen des auf einem Untergrund aufgeklebten Sicherheitsetiketts zu bewirken.

In order to solve the stated task, it is comprehensive in the case of a security label with several layers

• a laser writable layer with black aluminum oxide, the laser writable layer having a top and a bottom which are arranged opposite to one another and point away from one another,
• at least one transparent protective layer, which is arranged in front of the laser-writable layer as seen in a first direction, in order to protect the laser-writable layer from external influences, the first direction of the Top to bottom faces, as well
• a contrast layer, which is arranged behind the laser-writable layer as viewed in the first direction, provided according to the invention that at least one of the several layers is designed as a fracture layer made of a brittle plastic film in order to prevent destruction of the at least one fracture layer and the laser-writable layer, and optionally one or several intervening layers, in the event of manipulation or detachment of the security label glued to a substrate.

According to what has been said above, it cannot be ruled out that one or more further layers, in particular protective layers, are arranged above or in front of the at least one transparent protective layer as seen in the first direction.

The at least one transparent protective layer does not have to be arranged directly in front of the laser-writable layer, i.e. one or more further layers can be arranged between the at least one transparent protective layer and the laser-writable layer.

The laser-writable layer appears dark, in particular black. The contrast layer serves to generate an optical contrast of the, in particular transparent, inscription in the laser-writable layer. In particular, the contrast layer can be white. The contrast layer does not have to be arranged directly behind the laser-writable layer, i.e. one or more further layers can be arranged between the laser-writable layer and the contrast layer, for example a laminating adhesive layer.

The at least one fracture layer can theoretically be formed by the laser-writable layer and/or by the at least one transparent protective layer and/or by the contrast layer and/or by at least one further layer be. If the laser-writable layer forms the fracture layer, the aluminum oxide of the laser-writable layer can be applied to a plastic film of the laser-writable layer, which plastic film is brittle or has the desired brittle properties.

Said destruction of the at least one fracture layer and the laser-writable layer, and optionally one or more layers lying in between, includes breaking open or tearing open.

Due to its brittleness, the fracture layer is reliably destroyed when the security label is manipulated or removed. According to what has been said above, the laser-writable layer, including any layers lying in between, is also destroyed when the fracture layer is destroyed. Accordingly, document authenticity is secured.

A characteristic value for the brittleness of a material is its elongation at break. In the case of plastic films with thicknesses of 10 μm to 100 μm, in particular from 12 μm to 100 μm, as are usually used in security labels, the latter is typically in the range of approx. 100% or even significantly more than 100%. For example, a 50 μm thick polyethylene terephthalate (PET) film has an elongation at break of 190% in the machine direction and 120% in the transverse direction. If the elongation at break of the plastic film is more than 60%, in particular more than 80%, there is in any case insufficient brittleness. In order to reliably achieve sufficient brittleness, it is provided in a preferred embodiment of the security label according to the invention that the brittle plastic film of the at least one fracture layer has an elongation at break of less than 20%, preferably less than 15%, particularly preferably less than 10%. having. These elongation at break values apply to the plastic film as such, ie considered alone - without the entire structure of the security label with the other layers.

The stated requirement for brittleness can be achieved in the case of plastic films of the usual thickness using the most varied of materials known per se. Accordingly, in a preferred embodiment of the security label according to the invention, the brittle plastic film of the at least one fracture layer is an acrylate film or a polyvinyl chloride film (PVC film) or a polyurethane film (PU film). Said foils are sufficiently brittle per se. Additional embrittlement, for example through targeted UV radiation, is not necessary. In addition, there is usually no significant additional embrittlement of the plastic films used during the manufacturing process.

In a preferred embodiment of the security label according to the invention, it is provided that the contrast layer is designed as a fracture layer. In this way, extremely compact structures can be realized with a minimum number of layers, it being possible for the contrast layer to be arranged directly or not directly behind the laser-writable layer, seen in the first direction.

In this case, a particularly preferred embodiment of the security label according to the invention provides that at least one further layer is arranged between the laser-writable layer and the contrast layer, the at least one further layer comprising at least one partial release lacquer layer. The at least one further layer can also comprise further layers in addition to the partial release lacquer layer, for example a layer of laminating adhesive. The partial separating lacquer layer is not completely continuous, so that certain symbols or characters can be seen when the security label is peeled off arise in order to further increase the document authenticity. The partial separating lacquer layer provides different adhesion between layers arranged in front of and behind the separating lacquer layer compared to the adhesion of these layers without an intermediate separating lacquer layer, in order to cause a detachment of certain shaped areas when the security label is removed or manipulated and to make the symbols mentioned become visible.

Alternatively or additionally, in order to increase the sensitivity of the security label to manipulation or removal, in a particularly preferred embodiment of the security label according to the invention there is provision for at least one further layer to be arranged between the protective layer and the laser-writable layer, with the at least one further layer having at least one partial release lacquer layer includes. In turn, the at least one further layer can also comprise further layers in addition to the partial release lacquer layer, e.g. a layer of laminating adhesive. Likewise, the partial separating lacquer layer is not completely continuous, so that certain symbols or characters appear when the security label is peeled off in order to (still) increase the authenticity of the document.

As mentioned, the most varied of shaped symbols can be produced by means of the partial release lacquer layer. Accordingly, in a particularly preferred embodiment of the security label according to the invention, it is provided that the at least one partial release lacquer layer is in the form of one or more letters, one or more characters, one or more symbols, one or more lines, one or more guilloches , one or more numbers or one or more characters. The corresponding shape(s) will be used when peeling off the security label due to the local different detachment of the layers adjacent to the partial release coating layer visible.

In a preferred embodiment of the security label according to the invention, it is provided that the at least one protective layer comprises a layer of a UV transfer lacquer. This represents a particularly favorable solution in terms of process engineering for the production of the at least one protective layer.

In this case, a particularly transparent layer of plastic, particularly PET, or a plastic film, particularly PET film, can first be provided, which is arranged immediately in front of the layer of UV transfer lacquer, seen in the first direction, and subsequently—typically already in front the application of the security label - is removed again (by peeling it off).

Analogously, it is therefore provided in a preferred embodiment of the security label according to the invention that the at least one protective layer comprises a layer made of a plastic film, in particular polyethylene terephthalate film (PET film).

Of course, cases are also possible in which the at least one protective layer consists of at least one layer of plastic film, in particular PET film, or is completely formed by this.

In the case of several protective layers, it is conceivable that these layers include or consist of different plastic films.

In particular, it can be provided that a protective lacquer layer is applied as the "topmost" layer or as the first layer seen in the first direction, which layer can be arranged over the said at least one transparent protective layer. This protective lacquer layer protects the surface of the Security labels from abrasion and can be designed in particular slightly matt. The latter reduces the reflection of the surface and can therefore prove to be advantageous if, for example, a barcode written in the laser-writable layer is to be read using a scanner. Accordingly, in a preferred embodiment of the security label according to the invention, it is provided that the at least one protective layer comprises a layer of a protective lacquer or printing lacquer.

Furthermore, a layer of a printable adhesion promoter can be provided above the at least one transparent protective layer—and below the protective lacquer layer mentioned. This proves to be beneficial, for example, if the security label is first delivered to a customer with the layer of adhesion promoter as the top layer, who can then print a logo, for example, on the adhesion promoter layer and then apply the said, in particular matt, protective lacquer layer.

In a preferred embodiment of the security label according to the invention, it is provided that the at least one protective layer comprises at least one fracture layer. Again, a very compact structure can be realized as a result. In this case, the fracture layer is preferably arranged immediately in front of the laser-writable layer, viewed in the first direction, so that the direct adhesion of the fracture layer to the laser-writable layer results in the greatest possible security for the destruction of the laser-writable layer if the fracture layer is destroyed.

As already mentioned, the contrast layer does not have to be arranged directly behind the laser-writable layer, seen in the first direction. In order to ensure the greatest possible contrast, however, it is A preferred embodiment of the security label according to the invention provides that the contrast layer is arranged directly behind the laser-writable layer, seen in the first direction. In terms of contrast, this guarantees optimal readability of what is written in the laser-writable layer.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail using exemplary embodiments. The drawings are exemplary and are intended to explain the idea of the invention, but in no way restrict or even conclusively reproduce it.

Fig. 1

eine schematische Schnittansicht einer auf einen Untergrund applizierten ersten Ausführungsform eines erfindungsgemäßen laserbeschreibbaren Sicherheitsetiketts

Fig. 2

eine schematische Schnittansicht einer auf einen Untergrund applizierten zweiten Ausführungsform des erfindungsgemäßen laserbeschreibbaren Sicherheitsetiketts

Fig. 3

eine schematische Schnittansicht einer dritten Ausführungsform des erfindungsgemäßen laserbeschreibbaren Sicherheitsetiketts

Fig. 4

eine schematische Schnittansicht einer auf einen Untergrund applizierten vierten Ausführungsform des erfindungsgemäßen laserbeschreibbaren Sicherheitsetiketts

Fig. 5

eine schematische Schnittansicht einer auf einen Untergrund applizierten fünften Ausführungsform des erfindungsgemäßen laserbeschreibbaren Sicherheitsetiketts

It shows:

1

a schematic sectional view of a first embodiment of a laser-writable security label according to the invention applied to a substrate

2

a schematic sectional view of a second embodiment of the laser-writable security label according to the invention applied to a substrate

3

a schematic sectional view of a third embodiment of the laser-writable security label according to the invention

4

a schematic sectional view of a fourth embodiment of the laser-writable security label according to the invention applied to a substrate

figure 5

a schematic sectional view of a fifth embodiment of the laser-writable security label according to the invention applied to a substrate

WAYS TO CARRY OUT THE INVENTION

The Figures 1 to 5 show schematic sectional views of embodiments of a security label 1 with several layers, which is a “laser-writable security label”, ie a security label 1 comprising a laser-writable layer 2 with black aluminum oxide. The laser-writable layer 2 has an upper side 4 and an underside 5, which are arranged opposite one another and point away from one another. Seen in a first direction 6, the upper side 4 is arranged in front of the lower side or the first direction 6 points from the upper side 4 to the lower side 5.

Seen in the first direction 6, a transparent protective layer 3 is arranged directly in front of the laser-writable layer 2 in order to protect the laser-writable layer 2 from external influences.

A contrast layer 7 , for example white, is arranged behind the layer 2 that can be written on by a laser, as seen in the first direction 6 , with the contrast layer 7 not having to follow the layer 2 that can be written on by a laser. If, as described above, the laser-writable layer 2 is written with a laser, the laser-writable layer 2 becomes transparent along the track of the laser beam, with the contrast layer 7 making said track particularly easily visible optically.

Typically, the contrast layer 7 can be applied to a substrate 9 with a self-adhesive layer 15, the substrate 9 being formed, for example, by a product whose authenticity is to be guaranteed by means of the security label 1.

In order to ensure document authenticity, it is provided with the security label 1 according to the invention that at least one of the several layers is formed as a rupture layer 8 from a brittle plastic film in order to prevent destruction of the at least one rupture layer 8 and the laser-writable layer 2, and optionally one or more layers lying in between , in the event of a manipulation or detachment of the security label 1 glued to a substrate 9.

To ensure optimum brittleness, the brittle plastic film of the at least one fracture layer 8 can have an elongation at break of less than 20%, preferably less than 15%, particularly preferably less than 10%.

1 shows a schematic sectional view of a first embodiment of the laser-writable security label 1 according to the invention. Seen in the first direction 6, the following sequence of layers results: the protective layer 3 formed by a transparent PET film 13 (PET=polyethylene terephthalate); the laser writable layer 2; a partial release lacquer layer 10, a laminating adhesive layer 11; the fracture layer 8, which is formed by a white acrylate film 16 and at the same time represents the contrast layer 7; the self-adhesive layer 15, with which the security label 1 is applied to the substrate 9.

If the security label 1 is manipulated or if an attempt is made to remove the security label 1 from the substrate 9, the fracture layer 8 breaks and destroys the one above it arranged layers, i.e. those layers which are arranged in front of the fracture layer 8 seen in the first direction 6, and thus in particular also the laser-writable layer 2.

The partial separating lacquer layer 10 is not completely continuous, so that certain symbols or characters also appear when the security label 1 is peeled off, in order to further increase the authenticity of the document. Here, the partial separating lacquer layer 10 provides different adhesion between layers arranged in front of and behind the separating lacquer layer 10 - i.e. in particular between the laser-writable layer 2 and the white acrylate film 16 or the laminating adhesive layer 11 - in comparison to the adhesion of these layers without an intermediate separating lacquer layer 10, in order to cause a detachment of certain shaped areas when removing or manipulating the security label 1 and to let the mentioned symbols become visible. For this purpose, the partial release lacquer layer 10 can in particular be in the form of one or more letters, one or more characters, one or more symbols, one or more lines, one or more guilloches, one or more numbers or one or more lettering exhibit.

2 1 shows a second embodiment of the security label 1 according to the invention with a particularly compact structure that manages with a minimum number of layers. Seen in the first direction 6 , the transparent protective layer 3 is again provided as the first layer, which in this case is formed by a transparent acrylate film 17 and thus also forms the fracture layer 8 at the same time. The laser-writable layer 2 is arranged directly behind the protective layer 3, so that if the fracture layer 8 is destroyed, the laser-writable layer 2 is also reliably destroyed.

The laser-writable layer 2 is in turn arranged directly on the contrast layer 7 , the contrast layer 7 being formed by a white lacquer layer 18 . The self-adhesive layer 15 with which the security label 1 is applied or glued to the substrate 9 is arranged behind the contrast layer 7 .

3 1 shows a third embodiment of the security label 1 according to the invention, the breakable layer 8 in turn being formed by the contrast layer 7 in that the contrast layer 7 is formed as a white acrylate film 16 . In this embodiment, the transparent protective layer 3 includes not only the transparent PET film 13, but also a transparent UV transfer lacquer layer 19, which represents a particularly favorable solution for the production of the at least one protective layer 3 in terms of process technology. The transparent PET film 13 arranged directly in front of the UV transfer lacquer layer 19 in the first direction 6 is usually removed again before the security label 1 is applied to the substrate 9 (by peeling it off), which can happen in different process steps. Correspondingly, in 3 the security label 1 is also not shown applied to the substrate 9 .

Seen in the first direction 6, the overall result is the following sequence of layers arranged one behind the other: the transparent PET film 13; the UV transfer lacquer layer 19; the laser writable layer 2; the (transparent) laminating adhesive layer 11; the white acrylate film 16; and the self-adhesive layer 15, with which the security label 1 can be applied to the substrate 9. If the fracture layer 8 is destroyed, all of the layers arranged above the fracture layer 8—and thus in particular the laser-writable layer 2—of the security label 1 applied to the substrate 9 are also reliably destroyed.

4 FIG. 1 shows a fourth embodiment of the security label 1 according to the invention, wherein the fracture layer 8 is again formed by the contrast layer 7 and a particularly compact structure can be achieved with a minimum number of layers. In this case, the transparent protective layer 3 is formed by a protective lacquer layer 20, which not only protects the surface of the security label 1 from abrasion, but can in particular be matt in order to prevent reflections and thus improve the readability, in particular by machine, of the layer in the laser-writable layer 2 coded information (symbols, writing, etc.). Seen in the first direction 6, the laser-writable layer 2 is arranged directly behind the protective lacquer layer 20 and immediately behind this is the contrast layer 7 or fracture layer 8 formed by the white acrylate film 16. Accordingly, the laser-writable layer 2 is destroyed with great reliability if the fracture layer 8 breaks or is destroyed. Only the self-adhesive layer 15 with which the security label 1 is applied to the substrate 9 is arranged behind the fracture layer 8 .

figure 5 shows a fifth embodiment of the security label 1 according to the invention, in which two fracture layers 8 are provided in order to guarantee a particularly thorough destruction of the security label 1 in the event of manipulation or an attempt to remove it. One of the two fracture layers 8 is formed by the transparent protective layer 3, which is designed as a transparent acrylate film 17. Seen in the first direction 6, the layer 2 that can be written on by a laser is arranged directly behind the transparent acrylate film 17, which layer 2 is correspondingly destroyed in a highly reliable manner if the transparent acrylate film 17 breaks or is destroyed. The laser-writable layer 2 is arranged with a laminating adhesive layer 11 on the contrast layer 7, which is formed by a white acrylate film 16 and so that the second fracture layer 8 is formed. The self-adhesive layer 15 with which the security label 1 is applied to the substrate 9 is arranged directly behind the contrast layer 7 .

REFERENCE LIST

1

security label

2

Laser writable layer

3

protective layer

4

Top of the laser writable layer

5

Underside of the laser writable layer

6

First direction

7

contrast layer

8th

fracture layer

9

underground

10

Partial release coating layer

11

laminating adhesive layer

13

Transparent PET film

15

self-adhesive layer

16

White acrylic film

17

Transparent acrylate film

18

White lacquer layer

19

UV transfer varnish layer

20

protective lacquer layer

Claims (12)

Comprising a security label (1) with multiple layers - a laser-writable layer (2) with black aluminum oxide, the laser-writable layer (2) having an upper side (4) and an underside (5) which are arranged opposite one another and point away from one another, - at least one transparent protective layer (3), which is arranged in front of the laser-writable layer (2) as seen in a first direction (6) in order to protect the laser-writable layer (2) from external influences, the first direction (6) being dependent on the Top (4) to the bottom (5) has, as well as - a contrast layer (7), which is arranged behind the laser-writable layer (2) as seen in the first direction (6), characterized in that
at least one of the multiple layers is designed as a fracture layer (8) made of a brittle plastic film, in order to prevent destruction of the at least one fracture layer (8) and the laser-writable layer (2), and optionally one or more layers in between, when the to bring about a security label (1) glued to a substrate (9). Security label according to Claim 1, characterized in that the brittle plastic film of the at least one fracture layer (8) has an elongation at break of less than 20%, preferably less than 15%, particularly preferably less than 10%. Security label according to one of claims 1 to 2,
characterized in that the brittle plastic film of the at least one fracture layer (8) is an acrylate film or a polyvinyl chloride film or a polyurethane film. Security label according to one of claims 1 to 3,
characterized in that the contrast layer (7) is designed as a fracture layer (8). Security label according to one of claims 1 to 4,
characterized in that the at least one protective layer (3) comprises a layer of UV transfer lacquer. Security label according to one of claims 1 to 5,
characterized in that the at least one protective layer (3) comprises a layer of protective lacquer or printing lacquer. Security label according to one of claims 1 to 6,
characterized in that the at least one protective layer (3) comprises a layer of a plastic film, in particular polyethylene terephthalate film. Security label according to one of Claims 4 to 7 and according to Claim 4, characterized in that at least one further layer is arranged between the laser-writable layer (2) and the contrast layer (7), the at least one further layer having at least one partial release lacquer layer (10) includes. Security label according to one of Claims 4 to 8 and according to Claim 4, characterized in that at least one further layer is arranged between the protective layer (3) and the laser-writable layer (2), the at least one further layer having at least one partial release lacquer layer (10) includes. Security label according to one of claims 8 to 9,
characterized in that the at least one partial Release lacquer layer (10) has the form of one or more letters, one or more characters, one or more symbols, one or more lines, one or more guilloches, one or more numbers or one or more lettering. Security label according to one of claims 1 to 3,
characterized in that the at least one protective layer (3) comprises at least one fracture layer (8). Security label according to one of claims 1 to 11,
characterized in that the contrast layer (7) is arranged directly behind the laser-writable layer (2) as seen in the first direction (6).

Images