EP3829892B1 - Light control film, document comprising a light control film, and method for producing a document comprising a light control film - Google Patents

Description

The invention relates to a light control film, which comprises at least one functional layer, which consists of a multiplicity of light-scattering microstructures aligned in a plane of extension of the functional layer, and a document, which comprises such a light control film, and a method for producing a document, which is equipped with a light control film is trained. The extension plane is preferably parallel to the document surface.

From the DE 10 2012 109 064 A1 a light control film is known which is formed with at least one security feature located therein. This light control film comprises a multiplicity of light-controlling microstructures, which are aligned parallel to one another and can be aligned perpendicularly to a plane of extension or inclined at an angle thereto. The light control sheet is transparent at a primary viewing angle. In this case, a first security feature cannot be visible. The first security feature can be visible in a different viewing angle or correct viewing angle to the light control film. In order to introduce the security feature, parts of the microstructures are destroyed by a laser beam, with the laser beam impinging on the light-controlling microstructures at an angle that differs from the primary viewing angle.

Such a light control film enables security features to be introduced by removing parts of individual microstructures or blackening or non-blackening of parts of individual microstructures.

From the DE 10 2006 021 961 A1 a security element for security papers, documents of value and the like is known. This security element comprises a transparent or translucent marking layer into which virtual recognizable markings can be introduced by blackening or partially blackening the marking layer.

In order to increase security against forgery in documents, in particular value and/or security documents, a colored design of the security document is increasingly being used.

From the WO 2011/124774 A1 a method for introducing a colored portrait as a security feature by means of laser inscription is known. This colored portrait is achieved by using a colored pre-print with alternating primary or primary colors red, yellow, blue or cyan, magenta, yellow and additional white areas contained in the colored pre-print that are blackened locally by pulsed laser radiation and with shades of gray be provided. The areas that are not blackened or not provided with shades of gray remain according to the colored form and give a colored impression of the portrait. The production of such a colored portrait has the disadvantage that only a low color saturation can be achieved.

The invention is based on the object of proposing a light control film and a document with such a light control film and a method for producing such a document in order to form a colored security document with a high color saturation.

This object is achieved by a light control film with at least one functional layer, which is formed by a large number of light-controlling microstructures aligned in a plane of extension of the functional layer, in which several or all microstructures of the functional layer are colored at least in regions and the security feature introduced into the microstructures is colored is trained. The colored configuration of the microstructures makes it possible for parts or areas of the microstructures to be removed when the security feature is introduced by means of a laser beam and for the remaining parts or areas of the microstructures to remain visible in color. The area-wise destruction of the microstructures allows any colored combinations or configurations of the security feature. In addition given by the design of the colored microstructures a good color saturation, which corresponds to the quality of a colored printed representation.

Provision is preferably made for the microstructures to be colored in one or more colors. These light-controlling microstructures are preferably structures that are very small and not visible to the naked eye. These structures preferably have a size in the micrometer range. By coloring the microstructures, a colored basic grid can be provided in the functional layer, for example. A uniform coloring can also be provided. Due to the uniform coloring of the microstructures, the same color effect can be retained regardless of the degree of destruction by the laser beam when the security feature is introduced.

Alternatively, it can be provided that the microstructures are coated in color or metalized in color. As a result, further effects for the colored design of the functional layer with the microstructures can be achieved.

It is preferably provided that the microstructures arranged in a row in the functional layer are designed to alternate in color. For example, a sequence of primary or basic colors red, yellow, blue or cyan, magenta, yellow can be repeated over and over again. Also, only two primary colors can be used consecutively. The alternating design and arrangement of the colored microstructures is fundamentally arbitrary and can also be adapted to the security feature to be achieved. One or more transparent microstructures can also be provided between one or more colored microstructures.

The microstructures of the functional layer are preferably designed as lamellae and are provided in a row in the functional layer. These preferably extend in one direction and preferably completely within the plane of extension of the functional layer.

The microstructures designed as lamellae are advantageously at an angle perpendicular to the plane of extension of the functional layer or starting from the vertical orientation, aligned at an angle of up to 1° to the plane of extent of the functional layer. In the last case, the slats are aligned almost parallel to the plane of extension. The lamellar microstructures are preferably inclined to one another in such a way that an upper lamella does not completely cover a lamella below it, viewed in the direction of the extension plane of the functional layer.

A transparent cover layer can advantageously be provided on a top side of the functional layer. This transparent cover layer can advantageously also be blackened by laser radiation. As a result, the colored security feature can additionally be blackened, at least at certain points or in certain areas, or provided with shades of gray, making the security feature even more forgery-proof.

A further advantageous configuration of the light control film provides a transparent cover layer on an underside of the functional layer. This allows the color effect of the functional layer to shine through to the outside. Alternatively, a colored or opaque top layer can also be provided in order to create a uniform or neutral underside.

Furthermore, it can preferably be provided that at least one intermediate layer is provided between the functional layer and the upper and/or lower cover layer. With such an intermediate layer, the functional layer can be neutralized or designed differently with regard to its color effect. This intermediate layer can have recesses or punched-out areas in the area in which the colored security feature is to be introduced by the laser beam. Alternatively, the functional layer can be located in the area of a window, where a change in the color components and thus a color effect can be achieved by means of laser radiation.

Furthermore, at least one security feature is preferably introduced into the microstructure 10 on one or both sides. This can be done optionally and depending on the design of the security document. Of Furthermore, a part of a security feature can be introduced into the microstructure 10 on one side and a complementary part of the security feature can be introduced into the microstructure on the opposite side, so that a complete security feature is preferably formed, which is visible from both sides. One or more lamellae can remain between the one part of the security feature and the opposite part of the security feature and still form the parts of the security features for the appearance of an overall security feature.

The object on which the invention is based is also achieved by a document with a composite body which comprises a light control film according to one of the embodiments described above with a colored security feature. In particular, this enables colored laser personalization.

The object on which the invention is based is also achieved by a method for producing a document, in particular a value or security document, which is formed from at least one light control film which comprises at least one functional layer with a large number of light-controlling microstructures formed in the plane of extent of the functional layer , wherein a security feature cannot be visible at a primary angle to the functional layer and can be visible at a different viewing angle, and the microstructure in the functional layer is oriented at an angle perpendicular to the plane of extension of the functional layer or inclined thereto, so that in the case of two adjacent microstructures a microstructure does not completely cover the underlying microstructure, in which several or all microstructures are at least partially colored and the at least one microstructure is processed with a laser beam and at least one area of the light-controlling microstructure is destroyed or removed to form the at least one colored security feature. This process allows colored in a simple and precise way Security features are produced in a document. This security feature is recognizable without additional tools and cannot be changed.

To produce the security feature, the laser beam is preferably aligned perpendicularly to the plane of extension of the functional layer or inclined at an angle deviating from the plane of extension perpendicular. The alignment and/or inclination of the microstructures, which can be designed as lamellae, can also be adapted within the functional layer, so that the colored security feature is visible in the viewing direction in which the colored light control film is translucent. The security feature may not be recognizable from a different perspective. The angle for introducing the security feature can also be reversed by at least partially destroying the microstructures by means of the laser beam, and thus the visualization of the at least one security feature can also be reversed.

Provision is preferably made for the laser beam to destroy one or more adjacent microstructures, at least in regions. One or more superimposed microstructures can also be destroyed. For example, in the case of two differently colored microstructures that are partially superimposed, an area of the upper microstructure can be removed so that the colored area underneath shows through in an enlarged manner. In the case of three or more superimposed microstructures, depending on the processing depth of the laser beam, for example the first and second or the first to third microstructures can be removed, so that the size of the area and the color of the translucent and visible area can be determined in each case.

Furthermore, it can be provided that at least one perforation is made in the functional layer as a security feature by the laser beam. A specific color effect for a correct viewing angle or a primary viewing angle can also be achieved in this way.

• Figur 1 eine perspektivische Ansicht einer ersten Ausführungsform eines Sicherheitsdokumentes mit einer Lichtsteuerfolie,
• Figur 2 eine schematische Schnittansicht durch das Sicherheitsdokument gemäß Figur 1,
• Figur 3 eine schematische Teilschnittansicht durch das Sicherheitsdokument gemäß Figur 1,
• Figur 4 eine perspektivische Ansicht auf eine Funktionsschicht der Lichtsteuerfolie,
• Figur 5 eine perspektivische Ansicht einer weiteren Ausführungsform eines buchartigen Dokumentes,
• Figur 6 eine schematische Seitenansicht einer Personalisierdatenseite des buchartigen Dokumentes gemäß Figur 5, und
• Figur 7 eine schematische Schnittansicht der Personalisierdatenseite entlang der Linie V-V gemäß Figur 6.

The invention and other advantageous embodiments and developments thereof are described and explained in more detail below with reference to the examples shown in the drawings. The features to be found in the description and the drawings can be used according to the invention individually or collectively in any combination. Show it:

• figure 1 a perspective view of a first embodiment of a security document with a light control film,
• figure 2 a schematic sectional view through the security document according to FIG figure 1 ,
• figure 3 a schematic partial sectional view through the security document according to FIG figure 1 ,
• figure 4 a perspective view of a functional layer of the light control film,
• figure 5 a perspective view of another embodiment of a book-like document,
• figure 6 a schematic side view of a personalization data page of the book-like document according to FIG figure 5 , and
• figure 7 a schematic sectional view of the personalization data page along the line VV according to FIG figure 6 .

In figure 1 a first embodiment of a document 11 is shown in perspective. This document 11 has an ID-1 format, for example. Such ID-1 formats are used, for example, for check cards, Visa cards, telephone cards, driver's licenses, health insurance cards, identity cards and/or other authorization IDs or access authorizations. Alternatively, such a document 11 can also be in an ID-3 format or in other formats.

The document 11 comprises at least one light control film 5. The document 11 is preferably designed as a composite body 4 which comprises the light control film 5 and at least one cover layer 6. A cover layer 6, 7 is preferably provided on an upper side of the light control film 5 and on the underside. The cover layers 6, 7 are preferably transparent over its entire surface. It is also possible for only partial areas to be transparent and for one or more windows to be formed, for example in order to make visible an image 19 which was introduced into an underlying layer. In addition, at least one further intermediate layer or intermediate layer 8 can be provided between the light control film 5 and the cover layer 6, 7 on one or both sides. For example, such an intermediate layer 8 made of a material that can be written on, such as paper, cardboard or plastic or a mixture thereof, can be provided, which extends over the light control film 5 at least in certain areas. Such an intermediate layer 8 can be used to apply an image 19 . Furthermore, an ICAO zone 21 or another area for applying personalization data 22 can be provided. Depending on the structure desired in each case, such a multi-layer composite body 4 can be produced by lamination and/or gluing.

In figure 2 12 is a schematic sectional view of document 11 in FIG figure 1 shown. In this sectional view, the light control film 5 is shown schematically enlarged, which includes a functional layer 9 within which microstructures 10 are provided. These microstructures are not visible to the naked eye. These structures can be in the micrometer range. The basic structure of such light control films is known from a product under the designation BSF 33.8 Vikuiti ^™ , which is available from the 3M Corporation, St. Paul, Minnesota, USA.

In figure 3 12 is a schematic sectional view of document 11 in FIG figure 1 shown. In this sectional view, the light control film 5 is shown schematically enlarged, which includes a functional layer 9 within which microstructures 10 are provided. The functional layer 9 is placed in a recess 49 of at least one compensating layer and/or at least one intermediate layer 8 . A cover layer 6.7 can be provided on top of this, or a separate window element. Two intermediate layers 8 are shown as an example. But it can several intermediate layers, corresponding to a normal card structure, can be used. The functional layer 9 can therefore also only partially extend in the extension plane of the document 11 .

The figure 4 shows a perspective view of the functional layer 9 with partially shown microstructures 10. In this perspective view in figure 3 the upper cover layer 6 is not shown visible. The microstructures 10 are provided on the lower cover layer 7, for example.

In the light control film 5 shown, the microstructures 10 are in the form of lamellae, which extend along an extension plane of the functional layer 9, in particular in the Y direction. The orientation of the lamellae within the functional layer 9 can also be in the X direction or at an angle in between.

According to the exemplary embodiment, the lamellar microstructures 10 are inclined at an angle with respect to the Z-axis. According to a first embodiment, which is not shown, these lamellae can be aligned perpendicularly to the plane of extent, ie lie in the Z-axis. According to the exemplary embodiment shown, these can be inclined in a range between 30 and 60° to the plane of extension. The inclination of the lamellar microstructures 10 can be in a range between 90° to the plane of extent and up to 1° to the plane of extent. The respective microstructures 10 are arranged and aligned with one another in such a way that they do not completely overlap one another. Even at an angular position of 1° with respect to the plane of extent, in a plan view of the functional layer 9 a front region of a lower microstructure 10 protrudes in relation to a microstructure 10 arranged thereabove.

The microstructures 10 are colored. Several microstructures 10 can be combined as a colored area. In such an area, the microstructures can be of one color or of different colors. It can also be provided as in figure 4 is shown that the microstructures 10 consecutively with each colored in a different basic or primary colour. For example, the lamella 41 can be colored blue, the lamella 42 green and the lamella 43 red. The order can also be reversed as desired. Alternatively, the colors cyan, magenta and yellow or other colors and/or color combinations can also be selected.

The color sequence of the slats 41 to 43 described above can then be repeated. This sequence can also be repeated as a mirror image. Furthermore, any mixture of colored microstructures 10 can also be assigned to one another.

In a color sequence of the slats 41, 42, 43, for example, two, three or more slats can be colored with the same color and then one or more slats can be colored with a different color.

It is also possible for transparent lamellae to be inserted between one or more consecutive colored lamellae.

Provision is preferably made for a colored personalization, such as a colored portrait, to be generated by appropriate laser processing of the colored slats of the light control film 5 .

In the sectional view according to figure 2 several security features 52, 53, 54, 55 are shown by way of example and not conclusively. These can each be provided in the document 11 as the sole security feature or in any combination. The security feature 52 is visible when viewed in the viewing direction 62 . In the case of this security feature 52, for example, a region of the lamella 41 is destroyed by the laser beam. As a result, a blue colored area of the lamella 41 is removed. The lamella 42 underneath is green, for example. Due to the eroded area of the overlying lamella 41, the underlying green color of the lamella 42 is visible and the eroded area appears green. Depending on the length and/or the width with regard to the destruction of the lamella 41 lying above, the color of the lamella 42 lying underneath becomes visible.

In the case of the security feature 53, which is visible when looking in the direction of arrow 63, two superimposed lamellae 42, 43, for example, have been destroyed in some areas, so that the layer 41, which is repeated in particular, is visible. Thereby, a contiguous area of the same color tone can be obtained from the lamella 41 of the first RGB area to the lamella 41 of the subsequent RGB area. If the destruction of the individual slats is offset in one of the directions in which the slats extend, the color interaction can be varied.

An additional effect can be achieved with this security feature 53 in that the destroyed area of the lamella 42 is larger than the underlying and destroyed area of the lamella 43 . As a result, the translucent color of the lamella 41 can be framed by the different color of the lamella 43 . This frame can in turn be framed in color by the lamella 42 .

These examples show that different color effects can be achieved by lining up the lamellae 41 to 43 in different colors and also by the degree of regional destruction of the lamellae 41 to 43 .

In figure 2 a further security feature 54 can also be seen in the viewing direction according to arrow 64 . This is a perforation of the functional layer 9. There is therefore a local destruction that extends completely through the functional layer 9. This can be in the Z-axis. An angular position deviating from this can also be provided. The length and width or the size of a diameter can be adapted to the function of the security feature 54 .

The security features 52, 53 can also be introduced into the functional layer 9 from both outsides. These can be directly opposite each other and can be seen from each side with the same orientation. Alternatively, when there are two security features 52, 53 lying opposite one another, the impression can be given that they have been completely introduced Security feature is, which appears colored translucent, with at least one lamella 41, 42 and / or 43 still remains between the introduced security features.

Furthermore, part of the security feature 52, 53 can also be introduced on one side and another part of the security feature 52, 53 on the opposite side, so that the entire security feature 52, 53 becomes visible when viewed according to arrow 62 or 63.

Another security feature 55 is shown schematically in figure 2 shown when looking in the direction of arrow 65. This involves blackening and/or brightening using a laser beam. This blackening and/or brightening can be introduced into the cover layer 6 and/or into an intermediate layer 8 that may be present. The blackening can also have different shades of gray. As a result, an inscription and/or an additional interaction with an underlying colored security feature 52, 53, 54 can take place.

In figure 5 a book-like document 11 is shown in perspective. This book-like document 11 is, for example, an identification document such as a passport. The document 11 comprises a book cover 12, for example. A data page 17 and one or more inner pages 18 are connected to one another to form a book block 15 via a seam 16 . The data page 17 can form the security document. If a book cover 12 and in particular the header 14 are provided, this header 14 or this header 14 can also be connected to the book cover 12 with the seam 16 to form the book block 15 . The inner pages 18 of the book-like document 11 can be used, for example, to accommodate visas, stamps or other entries. The data page 17 consists of a data carrier 20 and a strap 23 attached to it. The data page 17, in particular the data carrier 20, can, for example, be designed according to the ICAO standard, in particular according to ICAO Doc 9303, 7th edition, and an image 19 of the Document holder, an OCR-readable ICAO zone 21 (also called "Machine Readable Zone" or English. "Machine Readable Zone", MRZ) and other personalization data 22 include. The personalization data 22 are provided within the data carrier 20 . The tab 23 of the data carrier 20 extends over the seam 16 away. This flap 23 also includes a seam area in which the seam 16 is formed. In addition or as an alternative to the seam 16, an adhesive and/or welded connection can also be provided in order to bind the flap 23 into the book-like document 11, in particular the book block 15.

In figure 6 a top view of the data page 17 is shown schematically. The data carrier 20 can include, for example, a transponder module 24 which includes an IC chip 25 and an antenna 26 . In addition or as an alternative, further electronic and/or other security elements, in particular diffractive security elements, can be incorporated and/or applied.

The tab 23 is connected to the data carrier 20 with the formation of an overlapping area 30 . The tab 23 comprises a web-like strip material which is connected to an outermost layer or layer of the data carrier 20, preferably by welding. In particular, the tab 23 can consist of the fabric-like strip material, preferably a PET fabric. With regard to the connection of the tab 23 of the fabric-like strip material for the tab 23 and the data carrier 20 and the structure of the data carrier 20 is fully on the DE 10 2012 213 913 A1 referenced.

In figure 7 a schematic structure of individual layers of the data page 17 with the tab 23 is shown. The document 11 according to the Figures 1 to 3 The embodiments described apply analogously to the structure of the data page 17 to which the tab 23 is attached. Alternatively it can also be provided that the tab 23 borders on the functional layer 9 and is provided between two outer cover layers 6 , 7 . The transponder module 24 can be integrated into the functional layer 9 or lie against an outside of the functional layer 9 and protected by the cover layer 6. The transponder module 24 can also be embedded in at least one intermediate layer 8 . The functional layer 9 can also only partially extend along the data carrier 20 .

Reference List

4. composite body 22 personalization data 5. light control film 23 tab 6. top layer 24 transponder module 7. top layer 25 IC chip 8th. liner 26 antenna 9. functional area 30 overlap area 10 microstructure 31 Outstanding area 11. document 35 front edge 12. book cover 49 recess 14 intent 52 security feature 15 book block 53 security feature 16 seam 54 security feature 17 data page 55 security feature 18 inside 62 arrow, line of sight 19 Picture 63 arrow, line of sight 20 disk 64 arrow, line of sight 21 ICAO zone 65 arrow, line of sight

Claims (15)

1. A light-controlling film having at least one function layer (9) which is formed by a multitude of light-controlling microstructures (10) formed in an extension plane of the function layer (9) and having at least one security feature (52, 53, 54, 55) formed in the light-controlling microstructures (10), said microstructures (10) being oriented normally with respect to the extension plane of the function layer (9) or inclined relative to the extension plane of the function layer (9), such that in the case of two adjacent microstructures (10), one of the two microstructures (10) is not entirely overlapped by the other microstructure (10) and several or all microstructures (10) are coloured at least in some regions, characterised in that at least one region of at least one light-controlling microstructure (10) has been removed for forming the at least one coloured security feature (52, 53, 54, 55) .
2. The light-controlling film as claimed in claim 1, characterised in that the security feature (52, 53, 54, 55) is invisible when looked at from a primary angle relative to the function layer (9) and becomes visible when looked at from an angle of vision deviating therefrom.
3. The light-controlling film as claimed in claim 1, characterised in that the microstructures (10) are single-coloured or multi-coloured, or in that the microstructures (10) are colour coated or colour metallised.
4. The light-controlling film as claimed in any of the preceding claims, characterised in that the microstructures (10) disposed next to one another in a row are of variable or alternating colours or in that transparent microstructures (10) are provided between coloured microstructures (10).
5. The light-controlling film as claimed in any of the preceding claims, characterised in that the microstructures (10) disposed next to one another in a row have a repetitive sequence of the RGB colours (red, green, blue) or of the CMY colours (cyan, magenta, yellow).
6. The light-controlling film as claimed in any of the preceding claims, characterised in that the microstructures (10) are shaped in the form of adjoining slats (41, 42, 43) which extend in a direction within the extension plane of the function layer 9.
7. The light-controlling film as claimed in claim 6, characterised in that the slats (41, 42, 43) are oriented at an angle of between 1° and 90° with respect to the extension plane of the function layer (9) and in that preferably all the slats (41, 42, 43) are oriented at the same angle with respect to one another.
8. The light-controlling film as claimed in any of the preceding claims, characterised in that the top surface of the function layer (9) has a transparent covering layer (6) provided thereon which may preferably be marked by laser radiation and/or in that the bottom surface of the function layer (9) has a transparent covering layer (7) or a white, coloured or opaque covering layer provided thereon.
9. The light-controlling film as claimed in any one of claims 7 or 8, characterised in that at least one intermediate layer (8) is provided between the function layer (9) and the upper and/or lower covering layer(s) (6, 7).
10. The light-controlling film as claimed in any of the preceding claims, characterised in that the at least one security feature (52, 53, 55) is incorporated into the microstructure (10) on one side and/or on both sides thereof, or in that one part of the security feature (52, 53, 55) is incorporated into the microstructure (10) on one side and the complementary part of the security feature (52, 53, 55) is incorporated into the microstructure (10) on the opposite side, such that preferably a complete security feature (52, 53, 55) is visible from both sides.
11. A document having a composite body (4) which comprises at least one image (19) and/or personalisation data items (22), characterised in that the composite body (4) comprises a light-controlling film as claimed in any one of claims 1 to 10 or is itself realised in the form of a light-controlling film as claimed in any one of claims 1 to 10.
12. A method of producing a document (11) which is formed of at least one composite body (4) that consists of a light-controlling film, or comprises at least one light-controlling film, which has at least one function layer (9) including a multitude of light-controlling microstructures (10), said microstructure (10) being oriented normally with respect to the extension plane of the function layer (9) or inclined with respect to the extension plane of the function layer (9), such that in the case of two adjacent microstructures (10), one of the two microstructures (10) is not entirely overlapped by the other microstructure (10), characterised in that the function layer (9) of the light-controlling film in which several or all microstructures (10) are coloured at least in some regions, is processed by a laser beam and at least one region of at least one light-controlling microstructure (10) is destroyed for forming a coloured security feature (52, 53, 54, 55) .
13. The method as claimed in claim 12, characterised in that for forming the coloured security feature (52, 53, 54, 55), the laser beam is oriented normally with respect to the extension plane of the function layer (9) or is oriented at an angle with respect to the extension plane of the function layer (9).
14. The method as claimed in any one of claims 12 to 13, characterised in that at least one microstructure (10), or a plurality of such microstructures arranged side by side, and/or at least one microstructure (10), or a plurality of such microstructures arranged on top of one another, are destroyed at least in some regions by the action of the laser beam.
15. The method as claimed in any one of claims 12 to 14, characterised in that at least one security feature (54) consisting of at least one perforation of the microstructures (10) is incorporated into the function layer (9) by the action of the laser beam.

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