CN104812862A

CN104812862A - Transparent security film

Info

Publication number: CN104812862A
Application number: CN201380061869.0A
Authority: CN
Inventors: C·黑勒曼
Original assignee: Tesa SE
Current assignee: Desarskopo Co ltd
Priority date: 2012-11-28
Filing date: 2013-11-14
Publication date: 2015-07-29
Anticipated expiration: 2033-11-14
Also published as: WO2014082867A1; CN104812862B; DE102012221796B3; EP2925825A1

Abstract

The invention relates to a multi-layer transparent security film, which is adhesively bonded to a substrate (5), wherein the security film comprises the following layers: an outer carrier layer (1), a separating lacquer layer (2), a partially applied release lacquer layer (3), an at least partially applied adhesive layer (4) for adhesively bonding to the substrate (5), wherein the adhesive force between the carrier layer (1) on one side and the separating lacquer layer (2) and possibly the release lacquer layer (3) on the other side and the adhesive force between the adhesive layer (4) on one side and the separating lacquer layer (2) and the substrate (5) on the other side are each greater than the cohesive force of the separating lacquer layer (2), wherein the cohesive force of the separating lacquer layer (2) is greater than the adhesive force between the release lacquer layer (3) and the separating lacquer layer (2) and the adhesive force between the release lacquer layer (3) and the separating lacquer layer (2) is possibly greater than the adhesive force between the release lacquer layer (3) and the adhesive layer (4), such that in the regions without the release lacquer layer (3) the security film separates due to a cohesive fracture or due to a mixed fracture that is mostly formed as a cohesive fracture, wherein both the cohesive fracture and the mixed fracture extend substantially horizontally through the separating lacquer layer (2), and in the regions having the release lacquer layer (3) the security film separates along an adhesive fracture between the release lacquer layer (3) and the separating lacquer layer (2) or possibly between the release lacquer layer (3) and the adhesive layer (4).

Description

Transparent safety film

Technical Field

The present invention relates to a multilayer transparent security film, a fragment of a security film and the use of a fragment.

Background

It should often be prevented, at least temporarily, that the packaging, in particular the goods packaging, the container as well as the doors, the valves, etc., is opened without authorization. To this end, such articles are equipped, for example, with a seal consisting of a segment of an adhesive film provided with an adhesive on one side. The seal can be applied with its adhesive face over the opening of the article, or wrapped around the package to be enclosed, or moved to the container and adhered to itself. If the seal is opened, it will typically be optically altered; after which tearing or plastic deformation occurs, for example. Since this change is irreversible, any attempt to operate on it can be unambiguously confirmed.

Such security systems for proving unauthorized opening are already known from the prior art. EP 1403190 a2 describes an inventive seal of an adhesive tape in the form of a segment, which is provided at least partially on one side with adhesive, which encompasses an article to be sealed and is bonded to the article with the adhesive present, wherein the adhesive tape has a carrier which is easy to tear, so that the carrier will tear irreversibly if the inventive seal is opened by pulling on both ends of the segment.

The security system has the following requirements for this type of security seal: i.e. it is required to be transparent so that e.g. the bottom, i.e. the surface of the package, container, door or valve, is discernible under the security seal. The transparent security seal should also be less noticeable as it does not affect or disrupt the packaging design, for example, and is accordingly also aesthetically recommended.

EP 0770251B 1 describes a transparent multilayer film which is particularly suitable for protecting data on documents. The multilayer film comprises a top layer, a rupturable layer which is irreversibly destroyed upon separation of the multilayer film, an adhesion-regulating substance which is applied partially in a pattern between the layers, and an adhesive layer for bonding substrates. The adhesion between the different layers and the cohesion of the breakable layer are set as follows: the breakable layer is broken or irreversibly deformed within the complementary range of the pattern for the adhesion-regulating substance. This patent uses the concept of "breaking" in relation to a breakable layer, so that the layer is irreversibly broken, for example by brittle fracture or by tearing in the transverse direction through the course of the layer, and the continuous layer will not exist in any way. The breakable layer may contain, for example, small glass microspheres as fillers to increase its brittleness.

Disclosure of Invention

Against this background, it is an object of the present invention to provide a transparent security film of simple construction and segments thereof, which show irreversible and clearly visible destruction during the separation test. Furthermore, it is an object of the invention to close a package, container, door, valve or the like by means of a section of a security film in such a way that any attempt to manipulate the section can be verified.

The aforementioned objects are achieved according to the invention by a multilayer transparent security film having the features of claim 1, a segment of the security film and the use of the segment for closing packages, containers, doors, valves and the like.

The multilayer transparent security film according to claim 1 bonded to a substrate which may be the surface of a package, container, door or valve and comprises the following layers: an outer support layer, a release paint layer (Trennlackschicht), a partially applied release paint layer (Releaseelackschichht) and an at least partially applied adhesive layer for adhesion to a substrate. The carrier layer is located on the outside, that is to say on the side remote from the substrate, after the security film has been bonded to the substrate. The release paint layer is generally all-roundAnd (4) applying. Advantageously, the partially applied release lacquer layer is applied in the form of a pattern or writing (Schriftzug).

The adhesion between the layers and the cohesion of the release paint layer are set as follows: the adhesion between the carrier layer and the release paint layer on the one hand and the release paint layer on the other hand, the adhesion between the adhesive layer and the release paint layer on the one hand and the substrate on the other hand, respectively, is greater than the cohesion of the release paint layer, the cohesion of the release paint layer is greater than the adhesion between the release paint layer and the release paint layer, and the adhesion between the release paint layer and the release paint layer is greater than the adhesion between the release paint layer and the adhesive layer, if possible (gebenenfalls). In this way, the security film is separated in the regions to which the release lacquer layer is not applied by cohesive fracture running essentially horizontally through the release lacquer layer. In the region of the applied release lacquer layer, the security film is either detached along the adhesive break between the release lacquer layer and the release lacquer layer or, if applicable, along the adhesive break between the release lacquer layer and the adhesive layer.

The safety film of the invention has the following advantages: although the security film does not include a pigmented or dyed print layer (Druckschicht), if the security film itself separates, a comparable proof of operation can be obtained. Without the pigmented or dyed layer, the transmission coefficient of the security film according to the invention (typically more than 95%) is significantly increased compared to the transmission coefficient of the security film with the pigmented or dyed layer (typically less than 75%).

The comparative best practice proved to be formed as follows: in the regions where the security film is separated by adhesive fracture, the release lacquer layer and the release lacquer layer or, where possible, the smooth surface of the adhesive layer are exposed. In the regions of the security film which are separated by the separating lacquer layer by cohesive fracture, the rough surface of the separating lacquer layer is exposed, which scatters the incident light and thus produces a very turbid surface. In contrast, a smooth surface scatters little light. If it is desired to close the security film again, air inclusions occur when it meets the rough surface of the release lacquer layer, so that a pronounced cloudiness remains, which causes light scattering at the interface between the rough surface of the release lacquer layer and the air inclusions. Air inclusions do not occur when compared with the release and release paint layers or, where possible, the smooth surface of the adhesive layer. The adhesion-broken regions thus also continue to remain transparent and are in clear contrast to the less-clean and less-transparent cohesive-broken hazy regions.

In a preferred embodiment of the security film, the side of the carrier layer facing away from the surface of the security film is roughened. In this way, the scattering effect at cohesive fracture along the separating lacquer layer is increased: in this case, the cohesive fracture, although passing substantially horizontally through the separating lacquer layer, nevertheless shows a position where the fine tip of the carrier layer stands out, the surface thus becoming rougher and the region of such cohesive fracture still becoming hazier. In particular, mixed fractures are involved here, since a large part of the two surfaces is exposed by cohesive fractures, but adhesive fractures are involved at those locations where the fine tips of the carrier layer stand out. The roughened side of the carrier layer remote from the security film surface also has the following advantages: the release paint layer adheres better to the carrier layer.

The surface may be roughened by mechanical or chemical treatment. The chemical treatment is, for example, etching by means of an acid or alkali solution.

It is advantageous to use a release coat of a release coat which is not crosslinked and thus has a lower cohesive energy.

It is often desirable to additionally introduce color features in addition to the presentation of well-contrasted proof of operation in the form of turbid and transparent regions. For this purpose, it is suitable, for example, to apply an opacifying layer partially in the security film. The opaque layer may be writing disposed between layers as follows: if the security film is separated, a first portion of the opaque layer remains on the carrier layer of the security film and a second portion of the opaque layer remains on the adhesive layer of the security film.

The release paint layer is advantageously applied on the carrier layer or on the entire surface, so that the release paint layer and the adhesive layer can be brought into contact with one another; or the release paint layer is applied over the entire surface of the adhesive layer so that the carrier layer and the release paint layer can contact each other. The full-scale application in both cases simplifies the manufacturing process.

If the release lacquer layer is applied to the carrier layer on all sides, an additional opaque layer can simply be applied in sections and positioned, for example, as follows: the pattern formed by the opaque layer is destroyed upon opening of the security film so that a portion of the pattern is on the portion of the security film which remains on the substrate and another portion of the pattern is on the portion of the security film which is separated from the substrate.

If the release lacquer layer is applied over the entire surface of the adhesive layer, the security film is very reliably and accurately separated in a predetermined manner when it is opened. Furthermore, no open adhesive surface remains after the rupture disk has been detached. Attempts to reclose the rupture disk, which are not apparent after separation, would therefore become particularly difficult.

In addition, the security film may have a uv-protective layer applied at least partially. The uv-protective layer is typically located between the adhesive layer and the other layers of the security film. In the manufacture of the security films, a uv protective layer is applied prior to the adhesive being placed on the security film. The adhesive can thus be applied in a hot-melt or wet-coating process without the aqueous release lacquer losing good release properties due to the action of heat when the hot-melt adhesive is applied or due to dissolution with water of a water-based dispersion of the adhesive. If no additional UV-protective layer is intended on the security film, it is advisable to apply an adhesive.

The security film of the invention may be further processed, for example cut into tapes, strips or labels. The shape of the fragment depends on its use. For example, the band is advantageous for sealing doors or valves. It is generally recommended to use a label that can be written on for package sealing or, if it is considered that a piece of security film is used for the reliability sealing of the package, a strip that surrounds the package and is glued to itself.

In a preferred embodiment the following are set for segments of such a security film: the adhesive layer is applied partially in such a way that a certain area of the security film segment remains uncoated with adhesive. This area is advantageously provided as follows: the rupture disk can be separated by a finger grasping a segmented region in the form of a handle defined by this area. The adhesive-free area thus fulfills the function of a handle, so that the segment is easy to grasp. Alternatively, it is also conceivable to apply the adhesive layer all over, but to cover in a non-adhesive manner in the area where the handle should be provided.

Drawings

The security film of the invention is subsequently illustrated in connection with fig. 1-8. Wherein,

FIG. 1: a schematic cross-sectional view of a closed security film,

FIG. 2: schematic cross-sectional view of a closed security film with an opaque layer,

FIG. 3: schematic cross-sectional view of a closed security film with a uv-protective layer,

FIG. 4: a schematic cross-sectional view of a closed security film having an opaque layer and a uv-protective layer,

FIG. 5: a section of a schematic cross-sectional view of a closed security film with a roughened carrier layer, which shows the interface region of the carrier face and the release lacquer layer,

FIG. 6: the section of the security film in fig. 5 after separation by mixed fracture, which essentially passes horizontally as cohesive fracture through the separating lacquer layer,

FIG. 7: on the left side of the page are shown three schematic top views of the security film according to fig. 1 from top to bottom in a closed, almost more than half open and reclosed state, respectively, and on the right side of the page are shown corresponding cross-sectional views of the security film from top to bottom,

FIG. 8: similarly to fig. 7, three schematic top views of the security film according to fig. 2 are shown from top to bottom in the closed, almost more than half open and reclosed state, respectively, and corresponding sectional views of the security film from top to bottom are shown on the right side of the page.

Detailed description of the preferred embodiments

Fig. 1 shows a schematic cross-sectional view of a closed security film with a carrier layer 1, a release lacquer layer 3 applied partially thereon, a release lacquer layer 2 applied over the entire surface thereof and an adhesive layer 4 applied over the entire surface thereof. The adhesive layer 4 completes the bond with the substrate 5, which substrate 5 may be, for example, the surface of a package, container, door, or valve. The rupture disk of fig. 1 is in a closed state, that is to say in an undamaged and unseparated state.

Fig. 2 shows a schematic cross-sectional view of a closed security film with an opaque layer. The security film differs from the security film of fig. 1 in that the release lacquer layer 2 adjoins the carrier layer 1 over the whole surface, rather than the adhesive layer 4 as in fig. 1. Furthermore, an opaque layer 7 is partially applied, either between the release lacquer layer 2 and the release lacquer layer 3 or between the release lacquer layer 2 and the adhesive layer 4.

FIG. 3 shows a schematic cross-sectional view of a closed security film with a UV-protective layer. The security film differs from the security film of fig. 1 in that a uv-protective layer 6 is arranged on the entire surface between the release lacquer layer 2 and the adhesive layer 4. The adhesive required for the adhesive layer 4 can be added without any problem by a hot-melt method or a wet coating method with the uv-protective layer.

Fig. 4 shows a schematic cross-sectional view of a closed security film with an opaque layer and a uv-protective layer. The security film differs from the security film of fig. 2 in that a uv-protective layer 6 is additionally provided which adjoins the adhesive layer 4 over the entire surface on the side of the adhesive layer 4 remote from the substrate 5.

Fig. 5 shows a schematic section through a closed security film with a roughened carrier layer 1, which shows the interface region between the carrier layer 1 and the release lacquer layer 2. The surface of the carrier layer 1 on its side remote from the security film is roughened and adjoins the release paint layer 2 with the roughened side.

Fig. 6 shows a section of fig. 5 after separation of the security film by mixed fracture, which essentially passes horizontally as cohesive fracture through the separating lacquer layer 2. The surface of the mixed fracture running on the roughened carrier layer 1 side shows the position of some points of the carrier layer 1 protruding from the surface of the release paint layer 2. The adhesive fracture between the carrier layer 1 and the release lacquer layer 2 can be seen precisely at these locations, since these locations together form a smaller area, or even do not occur at all, when measured over the entire surface of the mixed fracture, so that this surface and the surface opposite it are referred to in this correlation as the surface of the adhesive fracture.

Fig. 7 shows three schematic top views from top to bottom in a closed, almost more than half open and reclosed state, respectively, on the security film according to fig. 1, on the left side of the page, and a corresponding cross-sectional view of the security film from top to bottom on the right side of the page, wherein, although the attached top view of the middle part shows almost more than half of the security film open, the cross-section of the middle part shows a fully open security film. The top view of the central part shows a checkerboard pattern of turbid areas 2a with rough surfaces revealed by cohesive force fractures and transparent areas 2b with smooth surfaces revealed by adhesive force fractures both in the parts of the security film remaining on the substrate 5 and in the parts of the security film separated from the substrate 5. The surface of the part of the security film remaining on the substrate 5 is the surface of the continuous release lacquer layer 2, which is rough and smooth in the regions 2a and 2b, respectively, of the checkerboard pattern. The surface of the part of the security film that is separated from the substrate 5 is a checkerboard pattern formed by the transparent areas of the release lacquer layer 3 with a smooth surface and the turbid areas of the release lacquer layer 2 with a rough surface. The lower plan view shows a reclosable security film with a checkerboard pattern of almost transparent regions 13 and a checkerboard pattern of turbid regions 12, the almost transparent regions 13 again being in contact with one another at the surface of the adhesion failure, i.e. at the surface of the separating lacquer layer 2 and at the surface of the release lacquer layer 3, and the turbid regions 12 being in contact with one another at the surface of the adhesion failure, i.e. at the surface of the two separating lacquer layers 2. The smooth transparent regions are shown in fig. 7 and 8 as spots, and the rough turbid regions are shown in white.

Fig. 8 shows, analogously to fig. 7, three schematic top views of the security film according to fig. 2 from top to bottom in the closed, almost more than half open and reclosed state, respectively, and corresponding sectional views of the security film from top to bottom on the right side of the page. On the side of the release lacquer layer 2 remote from the carrier layer 1, an opaque layer 7 is applied in sections and is in the form of four numerals 1, 2, 3 and 4. The position of the opaque layer 7 within the layer sequence of the security film is separately identifiable in the three cross-sections to the right of the page. The cross section of the middle part shows an open security film which is partly broken by adhesion and partly separated by cohesive force breaking. Depending on the position of the opaque layer 7, the opaque layer 7a is either located in the part of the security film that remains on the substrate 5, i.e. between the release lacquer layer 2 and the adhesive layer 4, or the opaque layer 7b is located in the part of the security film that is separated from the substrate 5, i.e. between the release lacquer layer 2 and the release lacquer layer 3.

Support layer

The carrier layer may comprise paper, thermoplastic film or a laminate of at least one of the two compositions. The coextrudate may be considered as long as the thermoplastic material is contained in the carrier layer. The thermoplastic material may comprise polyethylene, in particular HDPE (high density polyethylene), polyester, in particular PET (polyethylene terephthalate), PP (polypropylene) and PVC (polyvinyl chloride), and is preferably uniaxially or biaxially stretched. Uniaxially stretched PP is characterized by its very high tear strength and low deformation in the length direction and is used, for example, as a carrier material in so-called "strapping". The carrier layer is transparent, preferably having a transmission factor of more than 95% in the spectral range visible to the human eye. The inverse of the transmission coefficient has a logarithmic relationship with the optical density of the carrier layer and, if the optical density of the carrier layer is known, this value can be determined by the lambert beer law.

The support layer, often a PET-based laminate, is generally 20 to 100 μm, preferably 30 to 50 μm, thick. The surface of the carrier layer can be roughened by chemical treatment, for example by etching with strong acids or strong bases. As acids, for example, oxidizing acids such as chromium sulfate or potassium permanganate mixed with sulfuric acid can be considered. In particular, PET films are frequently etched with trichloroacetic acid or with caustic potash solutions.

Italian companies Coveme SPA and polifribra SPA treat the surface of the film with trichloroacetic acid accordingly. The product name sold by Coveme corporation isSuch double-side treated membranes of HPH 100. Trichloroacetic acid is used at very high concentrations and acts on the membrane surface for a long time. In a continuous etching process, the orbital speed of the film surface to be etched is therefore relatively slow, approximately 30 to 50 meters per minute, and the drying temperature is only slightly above 100 ℃. During corrosion of the PET film, ester groups hydrolyze at the surface and generate polar hydroxyl, carboxyl, and carboxylate groups. The film surface therefore presents a better adhesion base for most release paints and stripping paints, which are likewise polar. In addition, the etching process also destroys crystallinity in the near-surface region of the film. The result was a distinct surface roughening.

Surface roughness refers to the height deviation of a truly measured interface from an ideal smooth average interface. The measured values can be evaluated, for example, as average roughness, average of height deviations, or as squared roughness, average of height deviations. The support layer has an average surface roughness of approximately 2 μm and from 1.5 to 2.5. mu.m, preferably from 1.8 to 2.2. mu.m.

Roughened and thus enlarged film surfaces are often used to strengthen the bond with pressure-sensitive adhesives (Haftklebstoff) or laminating adhesives (Kaschierkleber). Another significant effect of roughening the film surface is related to the invention in that light scattering at the interface with air or other materials having a density that differs significantly from the film density is enhanced. In this way, a strong contrast is formed between this interface region and the following interface regions: the roughened surface is contiguous with a material having a density approximating the film density and light scattering therein is small. In the closure security film according to the invention, the roughened film surface is only contiguous with: this material had a density similar to the film density, so no contrast occurred. Upon separation of the inventive security film, two interfacial regions occur, so that the opened segment of the inventive security film is clearly different from the unopened segment.

Stripping paint layer

The release lacquer includes, in particular, clear, water-based, solvent-containing and uv-curing (that is to say curing by means of uv radiation) varnishes (Klarlacke) which can be applied to the carrier layer by means of different printing processes (Druckverfahren), for example flexographic, offset, screen, transfer and inkjet printing. To improve the separation effect, a silicon-containing substance can be added to the stripping lacquer, which can reduce its surface energy. The application amount of the release lacquer is advantageously from 1 to 7g/m²。

Separating paint layer

Suitable separating lacquers are materials with exceptionally low cohesion, in particular printable or scratch-resistant, water-based or solvent-containing substances. Low cohesive energy can be achieved by high contents of fillers such as barium sulfate, kaolin, talc or chalk, which are advantageously added as colloidal filler dispersions having a particle size of less than 1 μm, in order to ensure that the transparency of the separating lacquer is as high as possible. Examples of such separating lacquers are resin dispersions, acrylate dispersions or polymer dispersions in general and solvent-containing polymer solutions whose polymer binder composition is preferably small-molecular and uncrosslinked and thus has very low cohesion. Particularly good results are achieved with aqueous dispersions consisting of waxes. The application rate of the separating lacquer is preferably 2 to 12g/m²。

Ultraviolet protective layer

Aqueous or solvent-containing UV-curing lacquers are used as UV-protective layers. The lacquer can be applied, for example, by a printing process or by a doctor blade process (rakelfahren).

Adhesive layer

Substantially all known adhesives with a high adhesive force on a substrate, for example a sticky bottom (haftgrond) to be packaged, such as synthetic rubber, natural rubber and acrylate adhesives, come into consideration as adhesives. Adhesive solutions, dispersions or hot melts can be mentioned here. The amount of adhesive applied to the support layer under pressure is preferably from 15 to 60g/m²Particularly preferably in the range of 20 to 30g/m²。

In particular, for one embodiment of the security film according to the invention in which the release lacquer layer is applied over the entire surface of the carrier layer, a partially applied release lacquer layer is located between the release lacquer layer and the adhesive layer and is not provided with a uv-protective layer: the adhesion layer is adjusted on the release paint layer such that the adhesion between the release paint layer and the adhesion layer is less than the adhesion between the release paint layer and the release paint layer. For this purpose, particularly suitable are polar adhesives with a moderate adhesion on steel of between 1.5 and 4N/cm, which are applied to the compressed carrier layer.

Opaque layer

Suitable as opacifying layers are all customary pigmented or pigmented, aqueous or solvent-containing, UV-curable printing lacquers or printing colorants. Preferably, uv-curing printing colours (Druckfarbe) are used, such as those manufactured by Flint, Zeller + Gmelin or Siegwerk.

List of reference numerals

Support layer 1

Separating paint layer 2

Separating lacquer layer region 2a with rough surface

The separating lacquer layer region 2b with a smooth surface

Stripping paint layer 3

The region 3b of the stripping lacquer with a smooth surface

Adhesive layer 4

Substrate 5

Ultraviolet protective layer 6

Opaque layer 7

An opaque layer 7a between the release lacquer layer 2 and the adhesive layer 4

Opaque layer 7b between release lacquer layer 2 and release lacquer layer 3

Turbid region 12 with cohesive fracture superimposed surfaces

Transparent region 13 with adhesive-breaking superimposed surfaces

Claims

1. A multilayer transparent security film adhered to a substrate (5), wherein the security film comprises the following layers:

-an outer carrier layer (1),

-separating the paint layer (2),

-a partially applied release paint layer (3),

-an at least partially applied adhesive layer (4) for adhering to a substrate (5),

wherein the adhesion between the carrier layer (1) and the release paint layer (2) on the one hand and possibly the release paint layer (3) on the other hand, the adhesion between the adhesive layer (4) and the release paint layer (2) on the one hand and the substrate (5) on the other hand are respectively greater than the cohesion of the release paint layer (2),

wherein the cohesion of the release lacquer layer (2) is greater than the adhesion between the release lacquer layer (3) and the release lacquer layer (2), and the adhesion between the release lacquer layer (3) and the release lacquer layer (2) is greater than the adhesion between the release lacquer layer (3) and the adhesive layer (4) when possible,

the security film is thus separated in the regions without the release lacquer layer (3) by cohesive fractures or by mixed fractures, which are in most cases designed as cohesive fractures, wherein the cohesive fractures and the mixed fractures run essentially horizontally through the release lacquer layer (2), and in the regions with the release lacquer layer (3) the security film is separated along the adhesive fractures between the release lacquer layer (3) and the release lacquer layer (2) or possibly between the release lacquer layer (3) and the adhesive layer (4).

2. The security film according to claim 1, wherein the surface of the carrier layer (1) on the side facing away from the security film is roughened.

3. The security film according to claim 2, wherein the surface of the carrier layer (1) on the side facing away from the security film is etched.

4. The security film according to any one of the preceding claims, wherein the release lacquer layer (2) adjoins either the carrier layer (1) on all sides or the adhesive layer (4) on all sides.

5. The security film according to any of the preceding claims, wherein the release lacquer layer (2) comprises an aqueous release lacquer.

6. The security film according to any of the preceding claims, comprising a partially applied opaque layer (7).

7. The security film according to claim 5, wherein the opaque layer (7) is arranged such that if the security film is separated, a first portion of the opaque layer (7b) adheres to the carrier layer (1) and a second portion of the opaque layer (7a) adheres to the adhesive layer (4).

8. The security film according to any of the preceding claims, comprising an at least partially applied uv-protective layer (6).

9. A segment of a security film according to any one of claims 1 to 8, wherein the segment is configured as a tape, strip or label.

10. The segment according to claim 9, characterized in that the adhesive layer (4) is partially applied in such a way that: an area of the security film segment which is arranged to separate the security film in such a way that a finger can grab the segment area in the form of a handle defined by this area remains free of adhesive.

11. Use of the fragment of claim 9 or 10 for closing packages, containers, doors, valves, etc.