EP2603885A1

EP2603885A1 - Foil element

Info

Publication number: EP2603885A1
Application number: EP11749337.9A
Authority: EP
Inventors: Sascha Mario Epp; John Anthony Peters; Ulrich Schindler
Original assignee: OVD Kinegram AG
Current assignee: OVD Kinegram AG
Priority date: 2010-08-11
Filing date: 2011-07-28
Publication date: 2013-06-19
Also published as: DE102010034156A1; JP2013541065A; JP5853346B2; KR20130108548A; KR101811906B1; TWI562453B; UA110348C2; US20130207848A1; TW201228093A; US9185797B2; WO2012019713A1

Abstract

The invention relates to a foil element (1) and to a method for producing such a foil element. The foil element (1) comprises a dielectric carrier layer (10), which spans an xy plane (E) of a Cartesian coordinate system having an x axis (61), a y axis (62) and a z axis (63), and at least one electrically conductive layer which is arranged on the carrier layer (10) and in which a conductor track (27) is formed in a frame-like region (5) of the foil element (1). The frame-like region (5) is formed by the area of a larger, outer rectangle (80) having sides (81, 82, 83, 84) each running parallel to the x axis (61) or y axis (62), from which area the area of a smaller, inner rectangle (90) with the same orientation as the outer rectangle (80) is cut out. The frame-like region (5) is subdivided into two frame sections (51, 52, 53, 54) running parallel to the x axis and two frame sections (51, 52, 53, 54) running parallel to the y axis, each of which sections is bounded by a bounding side (81, 82, 83, 84) of the outer rectangle (80) and a side (91, 92, 93, 94) of the inner rectangle (90) directly adjacent to the bounding side (81, 82, 83, 84) of the outer rectangle (80) and parallel thereto and subdivides the conductor track into conductor track sections (71a to 71d, 72a to 72d, 73d). A mechanical property of the carrier layer (10) is different along the x axis (61) and the y axis (62). More than 50% of the length of at least one conductor track section (71a to 71d, 72a to 72d, 73d) runs obliquely to the x axis (61) and the y axis (62), seen parallel to the z axis (63).

Description

film element

The invention relates to a film element with a dielectric carrier layer and at least one arranged on the carrier layer, electrically conductive layer, and a method for producing such a film element.

DE-B-102007030414 describes a method for producing an electrically conductive structure on a dielectric carrier substrate, such as a PET film (PET = polyethylene terephthalate). In this case, first a conductive layer, a so-called seed layer, in the form of a conductor track, for example an RFID antenna, by pattern-shaped printing of a conductive

Printed matter, for example, bound in a dispersant metal particles formed on the surface of the carrier substrate (RFID = Radio Frequency Identification). Subsequently, the printed seed layer is galvanically reinforced to form the electrically conductive structure by a metallic

Coating by applying a current flow in an electrolyte containing a dissolved coating metal is deposited on the conductive layer.

It is known that film elements which are subjected to elevated temperatures, for example during a lamination process, become wavy can, which can have significant disadvantages. For example, DE-A-102006029397 describes a plastic carrier film with a plastic carrier film arranged thereon

Security element, wherein the carrier film after a lamination of the

Carrier film with another plastic film and a cooling of the

Layer composite in the area of the security element shows an orange peel effect in such a way that the security element appears wavy on its entire surface. This problem is caused by tempering the carrier film before

Solved the release of the security element, as this apparently a local

Reduction of internal stress in the carrier film causes.

The invention is based on the object of specifying an improved film element and a method for producing such a film element.

The object is achieved by a film element comprising a dielectric carrier layer which spans an xy plane of a Cartesian coordinate system having an x-axis, a y-axis and a z-axis, and at least one electrically conductive layer arranged on the carrier layer, in the in a frame-shaped region of the film element, which is formed by the surface of a larger, outer rectangle with each parallel to the x-axis or y-axis extending sides, from which the surface of a smaller, inner

Rectangles with the same orientation as the outer rectangle is recessed, a conductor track is formed, wherein the frame-shaped portion is divided into two parallel to the x-axis and two parallel to the y-axis frame sections, each of a limiting side of the outer rectangle and a the limiting side of the outer rectangle immediately adjacent and parallel side of the inner rectangle are limited and the

Subdivide conductor track into conductor track sections, wherein a mechanical

Property of the carrier layer along the x-axis and the y-axis

is different, and wherein at least one track portion, viewed parallel to the z-axis, extends over more than 50% of its length obliquely to the x-axis and the y-axis. This object is further achieved by a method for producing a film element, comprising the steps: providing a dielectric support layer, which is an xy plane of a Cartesian

Coordinate system spans with an x-axis, a y-axis and a z-axis, wherein a mechanical property of the carrier layer along the x-axis and the y-axis is different; Applying at least one electrically conductive layer to a surface of the carrier layer; and forming a conductor track in the at least one electrically conductive layer in a frame-shaped region of the film element, which is formed by the surface of a larger, outer rectangle with sides parallel to the x-axis or y-axis, from which the surface of a smaller, inner rectangle with the same orientation as the outer rectangle is recessed, wherein the frame-shaped portion is divided into two parallel to the x-axis and two parallel to the y-axis frame sections, each of a limiting side of the outer rectangle and one of the delimiting side of outer edges of immediately adjacent and parallel side of the inner rectangle are limited and subdivide the conductor into conductor track sections, such that at least one conductor track section, seen parallel to the z-axis, to more than 50% of its length obliquely to the x-axis and the y-axis runs. A conductor track section runs in a single frame section. So there is an assignment of a conductor track section to a specific

Frame section. One or more trace portions may be associated with a particular frame portion. One aspect of the invention is based on the known fact that an industrially produced carrier layer in the form of a plastic film usually has two excellent directions in a plane spanned by the carrier layer, the so-called main relaxation directions in which the

Carrier layer has very different mechanical properties. One of these two excellent directions for plastic films can be the

Direction of rotation, which corresponds to a production direction in which the film is moved during its production. The other excellent direction at Plastic films preferably runs transversely to the direction of travel. Usually, in the case of plastic films, the running direction is referred to as the longitudinal direction or machine direction ("Machine Direction", abbreviated to MD) and the direction preferably perpendicular thereto as the transverse direction ("Transverse Direction", abbreviated TD). A comparable situation exists with machine manufactured papers: The

Direction of travel is a common statement in papers, which refers to the

Alignment of the paper fibers refers parallel to the direction of the paper machine. This anisotropy of the plastic film is known, for. B. of biaxially oriented polypropylene films, short BOPP films (BOPP = Biaxially Oriented Polypropylene). Many properties of polypropylene films, such as mechanics, appearance and barrier effect, can be improved by stretching the film. The stretching leads to a detectable directional molecular orientation and thus to the anisotropic nature of the film.

In conventional film elements with a dielectric carrier layer and at least one electrically conductive layer arranged thereon, in which a conductor track is formed in a frame-shaped region of the film element, the conductor track, which is z. B. forms a copper antenna coil, on the major part of its length the Haupttrelaxationsrichtungen. In the manufacture of lamination products or lamination intermediates such as a prelaminated inlay ("prelamel" for short) or an "electronic passport cover" (envelope for an RFID inlay ID document) using these conventional film elements, rippling may occur on the film Mimic the product so that the product can no longer be used (ID = Identification).

This ripple can already be seen on the conventional film element, but is not disturbing in the rule. Only after the conventional film element has been exposed to elevated temperatures, for. B. during lamination with temperatures of about 100 ° C, this ripple can so

be pronounced that it is no longer tolerable. This can cause the ripple penetrate except for outer layers of a laminate and there appear as optically and / or tactually perceptible, disturbing waves in appearance.

The extent to which this waviness appears depends on the thickness of the carrier layer, the thickness of the conductive layer and the exact course of the conductor track on the carrier layer. With sufficiently thick carrier films with more than 300 .mu.m, preferably more than 500 .mu.m thick thickness due to the stability of the films no or only slightly pronounced, tolerable waves. However, if the layer thickness of the carrier layer lies in a range of less than 300 μm, the ripple appears disturbing. Depending on the thickness of the carrier layer, the waviness is also influenced by the thickness of the conductive layer applied to the carrier layer. If the thickness of the conductive layer is relatively large compared to the carrier layer, the resulting ripple is comparatively strong, i. the ripple appears to a high degree. If the thickness of the conductive layer is relatively small compared to the carrier layer, the resulting ripple is comparatively small, i. the ripple appears to a small extent. This is due to the fact that a conductive layer thick relative to the carrier layer has a high mechanical stability and thus generates undesirable mechanical stresses between the carrier layer and conductive layer, which interfere during or after the lamination disturbing appearance. The thicker and more stable the support layer is relative to the conductive layer deposited thereon, the lower the level during or after lamination

be occurring ripple. For example, the waviness of a carrier layer with a thickness of about 300 .mu.m, to which a conductive layer having a thickness of about 10 .mu.m is applied, is only slightly noticeable. For example, however, the resulting ripple of a carrier film with about 50 pm thickness, to which a conductive layer is applied with about 10 pm thickness, more noticeable. One explanation for this phenomenon is that stress states between the carrier layer and the at least one electrically conductive layer arranged thereon, in particular the one or more conductor tracks, in the As a result, relaxation of the material of the carrier layer occurs, which, however, can not follow the material of an overlying electrically conductive layer, which leads to the observed ripple.

The film element according to the invention is now distinguished from conventional film elements in that an essential part of at least one conductor track section of the conductor track, preferably more than 50% of its length, does not extend in the main relaxation directions of the carrier layer but in directions deviating therefrom, ie. H. at an angle to the

Hauptrelaxationsrichtungen. Will the film element of the invention

Temperatures in a range of about 100 ° C or more exposed, for example, during a lamination process, for arranging further film layers on the film element or when connecting a chip module with the formed as an antenna coil, is characterized by

inventive course of the conductor prevents formation of a ripple in the film element. With the film element according to the invention is thus that of conventional film elements with a dielectric

Carrier layer and arranged thereon an electrically conductive structure known phenomenon avoided that the film element depending on the thickness of the support layer in a thermal treatment during the

Further processing can be wavy. The oblique to the x-axis and y-axis extending parts of the conductor track thus form voltage compensation elements that can compensate for existing voltages in the film element.

Another aspect of the invention is based on an increase in the track length resulting from the predominantly oblique course of the track with respect to the x-axis and the y-axis. The conductor track with the increasing electrical resistance of the conductor corresponds, if the conductor as an antenna, for. B. a transponder antenna for RFID tags, is formed, a lowering of the quality factor Q, also called Schwingkreisgüte or Q-factor ("Q-value")., While especially in a double-sided antenna a very high quality factor in the range Q> 30 is for certain

Applications that use a very high data transfer rate benefit from a reduced quality factor for communication stability. Thus, in applications where a modification, in particular a reduction, of the quality factor is advantageous, the film element according to the invention offers greater design freedom in finding an antenna layout which is optimally adapted to the respective application than a conventional film element. It is to be regarded as favorable that an oblique, z. B. curved, conductor track guide has no significant change in the inductance of the conductor track.

The film element according to the invention is particularly suitable for

Mass-produced products such as RFID tags, credit cards, smart cards, passport books and the like, which require cost-effective production in a small footprint

Advantageous embodiments of the invention are designated in the subclaims. According to a preferred embodiment of the invention, at least one electrode surface which is electrically connected to the conductor track is formed in the at least one electrically conductive layer. The at least one electrode surface may serve as a contact point for a chip module and / or as a via-contact point to an electrode surface arranged on the opposite surface of the carrier layer.

The layer thickness of the carrier layer is preferably between 12 and

250 μηι, more preferably between 50 and 100 pm. The carrier layer here preferably consists of a plastic film such as a PET, PET-G, PVC, PC, PP, PS, PEN, ABS, or a BOPP film, of synthetic paper or a laminate composite of two or more such layers (PET-G = PET with glycol, PVC = polyvinyl chloride, PC = polycarbonate, PP = polypropylene, PS = polystyrene; PEN = polyethylene naphthalate; ABS = acrylonitrile-butadiene-styrene copolymer). Furthermore, it is also possible for the carrier layer to be multilayered and to consist, for example, of a plastic film and one or more decorative layers.

The film element according to the invention preferably has a substantially rectangular shape and the y direction corresponds to the direction of the longer dimension of the carrier layer. The layer thickness of the electrically conductive layer is preferably between 1 and 30 μm, more preferably between 8 and 20 μm. The layer thickness of the electrically conductive layer may in this case be constant or not constant. The at least one electrically conductive layer is preferably composed of layers or contains a metallic, electrically conductive material, for example aluminum, copper, silver, chromium, gold or a

Metal alloy. Furthermore, it is also possible for the at least one electrically conductive layer to consist of or contain another electrically conductive material, for example an electrically conductive polymer, graphene or a transparent, electrically conductive material, for example ITO (= indium tin oxide).

According to a preferred embodiment of the invention falls the

Diagonal intersection of the inner rectangle with that of the outer rectangle together, so that the respective opposite frame sections have the same width. It is also possible that all frame sections of the frame have the same width. The frame-shaped region forms a circumferential, self-contained corridor, preferably the

Diagonal intersection of a product formed from the film element with a rectangular shape, z. B. a smart card rotates.

It is advantageous if the at least one conductor track section is at least 80%, preferably at least 90%, of its length oblique to the x-axis and the y-axis runs. The undesirable waviness of the film element negatively correlates with the portion of the conductor track in which the conductor does not run along the main relaxation directions; in other words, the greater the ratio of the sum of the sections in which the track runs obliquely to the x-axis and the y-axis, to the total length of the track, the lower the waviness forming on the film element.

It is possible that the at least one conductor track section in its inclined portion wave or zigzag, z. B. triangular or sawtooth-shaped, runs. A wavy or a zigzag

Track has only marginally low or no track shares, in which the track runs along the Haupttrelaxationsrichtungen. Therefore, a wavy or a zigzag running conductor track is advantageous in order to avoid undesirable waviness of the film element. It is possible that the at least one conductor track section forms a track pattern that consists of a plurality of similar, interconnected individual elements

is composed.

It is advantageous if the y-direction indicates the machine direction of the carrier layer and the x-axis indicates the transversely extending transverse direction of the carrier layer. These two directions, which are distinguished in the carrier layer, are due to a preferred molecular orientation in the material of the carrier layer

characterized, the z. B. spectroscopically or by measuring optical

Properties such as birefringence or dichroism can be determined. Along the machine direction and transverse to the transverse direction of the support layer have mechanical properties such as the modulus of elasticity, short: modulus of elasticity, tensile strength, elongation at break, elongation at break or impact resistance, but also the thermal instability or shrinkage on average significantly deviating measured values.

It is possible that the mechanical property is a deformation behavior such as a compressive or tensile strength, an internal stress in the material of the carrier layer or a relaxation behavior, e.g. B. a stress relaxation, in particular a occurring during a thermal treatment at elevated temperatures relaxation of the material of the carrier layer, for. B. during a

Lamination process at temperatures of about 100 ° C, is.

It is preferred that the conductor strip comprises a coil, in particular as an electromagnetic coupling element, for. B. an antenna, serving coil forms, wherein at least one turn of the coil rotates the inner rectangle. The coil preferably has 1 to 10, more preferably 1 to 4 turns. There is one turn of the coil in each case in four

Divided conductor sections, which extend over each one of the frame sections.

According to a preferred embodiment of the invention, the length of a first side of the inner rectangle is at least 50%, preferably at least 60%, the length of a side of the outer rectangle parallel thereto, and the length of a side of the inner perpendicular to the first side of the inner rectangle Rectangles is at least 70%,

preferably at least 75%, the length of a parallel side of the outer rectangle. In this case, the frame-shaped region forms a narrow circumferential surface band, in which the conductor track is arranged.

It is preferable that the length of a first side of the inner rectangle is in the range of 30 to 40 mm and the length of a side of the outer rectangle parallel thereto is in the range of 45 to 55 mm. It is further preferable that the length of a side of the inner rectangle perpendicular to the first side of the inner rectangle is in the range of 60 to 70 mm and the length of a side of the outer rectangle parallel thereto is in the range of 75 to 85 mm. It is further preferred if the circumferential surface band formed by the frame-shaped region has a width in the range of 5 to 10 mm. It is further possible for the film element to comprise a first electrically conductive layer, in which a first conductor track is formed in the frame-shaped region of the film element, and a second electrically conductive layer, in which a second conductor track is formed in the frame-shaped region. In this case, the carrier layer is arranged between the first and second electrically conductive layer. In addition, in this case, the first and the second conductor track are coupled to one another to form an antenna structure, preferably by a through-connection penetrating the carrier layer. And at least one

Track section of the first and second conductor track has the said oblique course. The coupled first and second conductor tracks preferably form a coil, in particular a serving as an antenna coil, z. B. an antenna of an RFID transponder.

According to a preferred embodiment of the invention, in the first and / or the second electrically conductive layer, a first and a second electrode surface are formed, each with the first and / or second

Conductor are electrically connected. In this case, the first and the second conductor track are preferably connected to one another via at least one electrically conductive through-connection through the carrier layer and / or capacitively or inductively coupled to one another.

By changing the mutual coverage, z. B. by an offset of the first conductor relative to the second conductor or a

Changing the width of one or both tracks, electrical

Properties such as the electrical capacitance C or the resonant frequency f of the antenna are changed and adapted to a specific application. It is possible that the first and second traces overlap completely according to a so-called "fill width overlap" (= FWO) It is also possible that the first and second traces are only in regions

For example, a first, coil-shaped interconnect may comprise two turns and a second, coil-shaped interconnect may comprise one turn, wherein Winding of the second conductor track, seen parallel to the z-axis, runs between the two turns of the first conductor track and overlaps them from both sides. The preferably first conductor track preferably has a conductor track width of 0.5 to 5 mm, more preferably 1 to 2 mm. It is possible that the width of the first conductor track is greater than or equal to or smaller than the width of the second conductor track. For example, a reduction of the overlapping area between the first and second conductor track can be achieved by a reduction of the conductor track width of the second conductor track. In this way, electrical properties such as the capacitance C or the resonant frequency f of the antenna can be changed and adapted to a specific application.

It is possible that the course of the at least one conductor track section is described by {x; y} coordinate pairs, which are represented by a preferably

periodic structuring function F (x or y) are defined. These {x; y} coordinate pairs refer to the Cartesian coordinate system, in the xy plane of which the carrier layer extends. In the frame sections extending parallel to the x axis, the course of the at least one track section is described by {x; y} coordinate pairs, which are defined by a structuring function y = F (x). In the extending parallel to the y-axis frame sections of the course of at least one

Track section described by {x; y} coordinate pairs, which are defined by a structuring function x = F (y).

In the case of a periodic structuring function F (x or y), the period of the structuring function is preferably selected smaller than twice the length of the respective frame section, in particular smaller than the single length of the frame section. As a result, a frame section has half the period of the structuring function, in particular a complete period of the structuring function. The frame sections preferably have lengths between 20 mm and 120 mm, more preferably between 35 mm and 80 mm.

It is preferred that the period of a periodic structuring function be chosen the smaller the higher the anisotropy of the mechanical

Characteristics of the carrier layer is. In this way, the at least one periodically structured conductor track section comprises the more periods the higher the anisotropy of the mechanical properties of the carrier layer. It is preferred if the structuring function F (x or y) is formed such that the ratio of a sum of the partial lengths of the at least one

Track section, in which the track section extends obliquely to the x-axis and the y-axis, to a total length of the at least one

Conductor track section is maximum.

It is preferred if the structuring function F (x or y) is a sine function of the form y = F (x) = A * sin (2 * π * Γχ + <p) or x = F (y) = A ^* sin (2 * TT * f * y + φ), where A is an amplitude, f is a frequency and φ is a phase angle. A conductor track section designed as a sine curve runs only in the maxima and minima of the sine curve parallel to the x-axis or y-axis, ie only in two individual points per period. The proportion of at least one

Track section, in which the conductor track section along the

Main relaxation runs, so in this embodiment is so low that the ripple of the carrier layer is practically minimal. Therefore, a sine curve forms a preferred course of the conductor track.

It is possible for at least two conductor track sections to show the said oblique course, wherein at least one parameter defining the structuring function F (x or y) has different values in the at least two conductor track sections. Parameters defining the substructuring function may be: amplitude, frequency, phase and shape of the

Structuring function F. For two in the same frame section Track sections, in which the track runs predominantly obliquely to the x-axis and the y-axis, the frequencies or the

Amplitudes of the respective conductor track section associated

Structuring functions F (x or y) to be coordinated if the distance between the two conductor track sections a certain threshold

below. Otherwise, it may come to a short-circuit forming contact between the conductor track sections. It can therefore be provided that the frequency or the shape of the

Structuring function F (x or y) changes continuously so that the

preferably wavy or zigzag in the same frame section extending conductor track sections have a constant distance from each other.

It is possible that all the conductor track sections running parallel to the x-axis or all of the conductor track sections running parallel to the y-axis are predominantly oblique to the x-axis and the y-axis. It is also possible that all conductor track sections show the said oblique course.

It is possible for two conductor track sections, which run in two different, parallel frame sections, to be symmetrical with respect to an axisymmetric axis extending parallel to the two parallel frame sections or with respect to a point symmetry point. It is also possible for two conductor track sections, which run in two different, parallel frame sections, to be substantially identical,

in particular their structuring functions have the same frequency, the same

Have amplitude and the same phase.

It is possible that the length of the at least one conductor track section is greater by approximately 0.5 to 30% than the length of a corresponding, not obliquely running conductor track section, in particular a track track section running parallel to the x-axis or y-axis. Characterized in that the conductor track in the at least one conductor track section, viewed parallel to the z-axis, extends predominantly obliquely to the x-axis and the y-axis, z. B. in one Waveform, increases the trace length compared to a conventionally formed trace, which runs in the at least one trace portion predominantly parallel to the x-axis or the y-axis. Thus, the electrical resistance R of the conductor increases. If on the two

opposite surfaces, d. H. Front and back, the carrier layer in each case one conductor track, d. H. a first and a second conductor track, which overlap each other, the oblique course of the conductor tracks also increases the absolute overlap area of the two conductor tracks. As a result, the electrical capacitance C of the conductor tracks increases. If the first or second interconnect forms an antenna or the first and second interconnect are coupled together to form an antenna, the frequency f of the antenna decreases due to the oblique course of the interconnect (s).

By structuring the printed conductor according to the invention and choosing the layer thickness of the printed conductor, the electrical properties of the printed conductor formed as an antenna can be influenced. It is possible that the increase in the conductor track length, which results from the predominantly oblique course of the conductor track, results in a higher antenna capacitance with a practically constant antenna inductance. It is possible to adapt the capacity of the antenna, in particular to reduce it by the overlapping area between two, preferably on two different surfaces of the

Carrier layer arranged conductor tracks is selected, in particular by a reduction of the conductor track width of one of the conductor tracks. An increase in the electrical antenna resistance resulting from the enlargement of the conductor track length, which results from the predominantly oblique course of the conductor track, can be achieved by increasing the layer thickness of the conductor track, for example by increasing the thickness of the conductor track. B. by building a thicker copper layer, again reduced.

The present invention thus offers, via the design of the oblique course of the conductor track (s), a variety of possibilities for adapting the electrical properties of the conductor track (s), in particular one formed thereby

Antenna. For the application and / or structuring of a first and second electrically conductive layer onto the carrier layer, methods which are synchronized with one another are preferably used. In this case, it is particularly advantageous if in a first step a structured electrically conductive base layer is applied to a first and a second surface of the carrier layer and then a galvanic reinforcing layer is applied to each of the base layers in a galvanic bath. The electroplating bath may have several partial baths and be currentless or else current-carrying, whereby individual partial baths may be currentless and other partial baths may be current-carrying. The electrically conductive base layer is in this case preferably by means of a

Structured printing process. Thus, for example, it is possible for a conductive material, for example a conductive ink or paste, to be printed in the areas on the first and second surfaces of the carrier substrate in which later in the first and second electrically conductive layers the first conductor track or the second Track should be formed. Furthermore, it is also possible that the base layer is applied in a first step over the entire surface of the first and second surfaces of the carrier layer, for. B. by means

Vapor deposition or by lamination as a thin metal layer, and then an etching resist is printed in the areas in which the first or second conductor to be formed in the first and second electrically conductive layer. Subsequently, the base layer is removed in the areas not covered by the etching resist by means of an etching agent, for example a lye, and then the etching resist is likewise removed. Further, it is also possible, the base layer by printing an etchant on the full-surface base layer or printing a washing mask before applying the

To structure a full-surface base layer or printed on an electrically conductive base layer in the areas in which no electrically conductive areas in the first and second conductive layer to be formed, a dielectric barrier layer, which prevents the galvanic deposition of the galvanic reinforcing layer in these areas. The For example, structured base coat can also be directly laminated or hot stamped or cold stamped.

The application of the conductive printing materials, the etching resist layer, the etchant and the dielectric barrier layer is preferably carried out by means of two synchronized printing units, wherein the one printing unit, the first surface of the carrier layer and the second printing unit imprints the opposite second surface of the carrier layer. The printing units are in this case preferably opposite each other on different sides of

Carrier layer arranged and coupled to each other via mechanical or electrical means or detected by means of sensors at the printing units register marks on the carrier layer to register accurate, d. H. to work in harmony with each other. Gravure printing, offset printing, screen printing, tampon printing or inkjet printing are preferably used as the printing method.

By doing so, a cost-effective registered, d. H. accurate registration structuring of the first and second electrically conductive layer achieved. Furthermore, this makes it possible to manufacture the galvanic reinforcing layers of the first and second electrically conductive layers simultaneously in a common electroplating process, whereby on the one hand production costs and production time can be reduced and, on the other hand, vias for connecting the conductive layers through the carrier layer without Additional expenses can be mitgefertigt, and thus the necessary process steps can be saved.

In the following the invention will be explained with reference to several embodiments with the aid of the accompanying drawings. 1 shows plan views of a first printed conductor, a second printed conductor and an overlay of the first and the second printed conductor in a conventional film element. Fig. 2 to 4 show schematic, not to scale sectional views of film bodies for explaining the inventive

Process for producing a multilayer film element.

Fig. 5 shows a plan view of a conductor according to a first

Embodiment of the film element according to the invention.

Fig. 6 shows plan views of the conductor track according to Fig. 5, a second

Conductor and a superposition of the first and the second conductor track according to a first embodiment of the invention.

FIGS. 7 to 12 show plan views of a conductor track, of a second conductor track and of a superimposition of the first and the second conductor track according to further exemplary embodiments of the invention.

Fig. 1 shows conductor tracks of a conventional film element. In part a) is a plan view of a first conductor 27 of the conventional film element, in part b) is a plan view of a second conductor 37 of the conventional

Foil element, and in part c) a plan view of a superposition of the first and the second conductor track according to the conventional film element shown. The first printed conductor 27 is arranged on a first surface of a carrier layer, not shown, which extends along an xy-plane E of a Cartesian coordinate system with an x-axis 61, a y-axis 62 and a z-axis 63. The second conductor 37 is on a second surface of the carrier layer opposite the first surface

arranged. In this case, the first and the second conductor track 27, 37 are arranged such that the conductor tracks 27, 37, as shown in part c), overlap, according to a PWO antenna design.

First contact surfaces 28, which are electrically connected to the first conductor track 27, are arranged on the first surface of the carrier layer. On the second surface of the carrier layer second contact surfaces 38 are arranged, which are electrically connected to the second conductor 37. The first and / or second contact surfaces 28, 38 serve as end faces of vias through the carrier layer to provide an electrical connection between the first trace 27 and the second trace 37 or as contact points for contacting a chip module to an electrical connection between the chip module and the first conductor 27 and / or the second conductor 37 to create. 4 shows a multilayer film element 1 with a carrier layer 10, a first electrically conductive layer 20 arranged on a first surface of the carrier layer 10, a first electrically conductive layer 20

overlapping first decorative layer 41, a first protective layer 43 applied to the first decorative layer 41, a second electrically conductive layer 30 arranged on a second surface of the carrier layer 10, a second decorative layer 42 covering the second electrically conductive layer 30, and a second decorative layer 42 applied to the second decorative layer 42 second protective layer 44. The carrier layer 10 is made of a plastic film, preferably a PET,

PET-G, PVC, ABS, polycarbonate or a BOPP film, synthetic paper or a laminate composite of two or more such layers with a thickness between 12 and 250 μπι, preferably formed between 50 and 100 μιτι. The carrier layer 10 here preferably consists of a transparent plastic film.

The protective layers 43 and 44 are protective lacquer layers of a thickness of 1 to 5 μm. However, it is also possible that it is in the

Protective layers 43 and 44 to a plastic film, synthetic paper or a laminate composite of both, with a thickness between 12 and 100 m, preferably from about 50 μιτι acts. In the simplest case, the decorative layers 41 and 42 are at least in a partial area around pattern-shaped color coat layers. However, it is also possible that the decorative layers 41 and 42 show one or more optically variable effects which serve as a security feature. For example, it is possible that the decorative layers 41 and 42 from a

Binder with optically active pigments mixed therewith, in particular effect pigments, such as metal pigments and / or thin-film-layer pigments and / or liquid-crystal pigments, or UV- or IR-activatable, luminescent pigments, consists (UV = ultraviolet, IR = infrared). Also in this case, the decorative layers 41 and 42 are preferably designed in a pattern and in this case preferably also show different representations.

The electrically conductive layers 20 and 30 are preferably layers or layer packages or contain a metallic, electrically conductive material, for example aluminum, copper, silver, chromium, gold or a metal alloy. Furthermore, it is also possible for the electrically conductive layers 20 and 30 to consist of or contain another electrically conductive material, for example an electrically conductive polymer or a transparent, electrically conductive material, for example ITO.

The production of the electrically conductive layers 20 and 30 and their configuration will be explained below with reference to FIGS. 1 to 4. In order to produce the electrically conductive layers, in a first step an electrically conductive base layer is applied to the layers in the xy plane E

extending carrier layer 10 applied. Thus, Fig. 2 shows the carrier layer 10, on one surface thereof a base layer 21 and on the

opposite, the other surface, the base layer 31 is applied.

The base layers 21 and 31 preferably consist of an electrically conductive printing material, for example of a metal particle, in particular silver particles or iron particles, containing electrically conductive ink or paste. The base layers 21 and 31 are in this case on the

Carrier layer 10 printed by a printing process, preferably by means of a gravure printing process in an order thickness of between 0.5 and 5 μιτι printed and then dried. The imprinting of the base layers 21 and 31 preferably takes place here by means of two synchronized printing units, wherein the one printing unit is arranged on one side of the carrier layer 10 and the second printing unit is arranged opposite to the first printing unit on the other side of the carrier layer 10. The synchronization of the two printing units is carried out by a mechanical coupling of the printing units or by a corresponding electrical coupling, d. H. exchange

corresponding synchronization data. By doing so, on the one hand, a high register accuracy, i. H. Positional accuracy achieved in the imprint of the base layers 21 and 31 and on the other hand a high

Production speed achieved. The thickness of the base layers 21 and 31 after drying is preferably 0.3 to 3 μητι.

In a second step, the film body comprising the carrier layer 10 and the base layers 21 and 31 is fed to a galvanic station, in which a galvanic reinforcing layer in the region in which the electrically conductive base layers 21 and 31 are provided

Electroplating process is deposited. For this purpose, the electrically conductive base layers 21 and 31 are contacted by electrodes and with a

Applied voltage potential, so that from the electrolyte of the plating bath, a galvanic reinforcing layer 22 and 32 is deposited on the base layers 21 and 31, as shown in Fig. 3. The deposition of the galvanic reinforcing layers 32 and 22 is preferably carried out in parallel in one and the same electroplating bath, whereby further advantages are achieved, as already explained above.

In this case, the galvanic reinforcing layers 22 and 32 are preferably made of a metallic material, which differs from the electrical conductive material of the base layers 21 and 31 is different. The layer thickness of the galvanic reinforcing layers 22 and 32 is preferably between 0.7 and 25 μηι, so that the total thickness of the electrically conductive layers 20 and 30 is between 1 and 30 μητι.

After a cleaning process and drying then the

Decorative layers 41 and 42 and the protective lacquer layers 43 and 44 applied and then the foil elements with another part of a

Security document integrated or for the time being by a cutting or

Punching process isolated.

However, the application of one or more of the layers 41, 42, 44 and 44 can also be dispensed with. The shape of the electrically conductive layers 20 and 30 is controlled by the printing process described with reference to FIG. 2. Fig. 1a

FIG. 1 b illustrates an embodiment of the electrically conductive layer 30 achieved thereby. In contrast to the PWO antenna design of FIG. 1 c, the sections of FIGS. 2 to 4 show a mutual arrangement of the FIGS Conductor tracks 20 and 30 according to a FWO antenna design, wherein the width of the conductor track 30 is smaller than the width of the conductor track 20.

Fig. 5 shows a plan view along a z-axis 63 of a Cartesian

Coordinate system with an x-axis 61, a y-axis 62 and the z-axis 63 on a film element according to the invention 1. The film element 1 comprises a carrier layer 10 which is parallel to the xy plane E of the coordinate system. The carrier layer 10 is oriented so that a mechanical

Property, e.g. B. the modulus of elasticity of the carrier layer 10, along the x-axis 61 and the y-axis 62 is different. The film element 1 also comprises a on a first surface, for. B. a front side, the carrier layer 10 arranged conductor 27. Die

Conductor 27 is formed in a frame-shaped region 5 of the film element 1, which by the surface of a larger outer rectangle 80, represented by the dashed boundary line, with two parallel to the x-axis 61 extending sides 81, 83 and two parallel to the y-axis 62

extending sides 82,84 is formed, from which the surface of a smaller inner rectangle 90, represented by the dash-dotted

Boundary line, with the same orientation as the outer rectangle 80 is recessed.

The film element 1 further comprises arranged on the first surface of the carrier layer 10 contact surfaces 38a, 38b, 38c, z. B. in the form of

Via pads or so-called bond pads for arranging an electrical component such as a chip module, which is electrically connected to the conductor track 27. The contact surfaces 38a, 38b, 38c are connected to the

Conductor 27 galvanically connected.

The frame-shaped region 5 is in two parallel to the x-axis 61 extending frame portions 51, 53 and two parallel to the y-axis 62 extending

Frame sections 52, 54, each of a limiting side 81,

82, 83, 84 of the outer rectangle 80 and one of the limiting side 81, 82,

83, 84 of the outer rectangle 80 immediately adjacent and parallel side 91, 92, 93, 94 of the inner rectangle 90 are limited.

The conductor track 27 is in the form of a coil, the coil comprising a first winding 71, a second winding 72 and a contact auxiliary structure 73d. The auxiliary contact structure 73d may serve to galvanically strengthen the contact surface 38c connected to the auxiliary contact structure 73d. The frame portions 51, 52, 53, 54 divide the conductor 27 in

Trace portions 71a to 71d, 72a to 72d and 73d. Thus, a first frame portion 51, the conductor track portions 71a and 72a, a second frame portion 52, the conductor track portions 71b and 72b, a third

Frame section 53, the conductor track sections 71c and 72c and a fourth frame section 54, the conductor track sections 71 d, 72d and 73d assigned.

The printed conductor sections 71b, 72b, 71d, 72d, 73d extend, as seen parallel to the z-axis 63, over more than 50% of their length obliquely to the x-axis 61 and the y-axis 62. The printed conductor sections 71b and 72b are wavy with the same and constant period, with the same and constant amplitude, with the same phase and with a constant distance to each other. The shape of the waves changes between a wave crest and a following wave trough. The conductor track portions 71b and 72b are wavy with the same period and constant distance from each other. The waveform has about 6 periods. The shape of the waves changes between a wave crest and a following wave trough.

The printed conductor sections 71 d and 72 d extend in substantially the same way as the opposite printed conductor sections 71 b and 72 b, only in mirrored orientation with respect to a mirror axis running parallel to the y-axis 62. The trace portions 73d are also waved with constant amplitude, with the same period and the same phase as the

Trace portions 71b, 72b, 71d and 72d but with a different waveform.

Fig. 6 shows in part a) a plan view of the first conductor 27 of FIG. 5, seen against the direction of the z-axis 63. Fig. 6 shows in part b) is a plan view of a second conductor 37, which on a second surface, for. B. a back side, the carrier film 10 is arranged, in the same direction as in part a). The second conductor 37 is divided by the frame sections 51 to 54 in the conductor track sections 74a to 74d. The second trace 37 has approximately 6 periods of the waveform in the trace portions 74b to 74d, respectively. In addition to the second conductor 37 and contact surfaces 39a, 39b and 39c are arranged on the second surface of the carrier film 10, of which only the

Contact surfaces 39b and 39c are electrically connected to the second conductor 37.

Fig. 6 shows in part c) a plan view of a superposition of the first conductor 27 and the second conductor 37, in the manner as they are arranged on the carrier film 10, in the same direction as in part a) and in part b).

Due to the similar course of the tracks 27, 37 in the

Frame sections 51 to 54 overlap the printed conductors 27, 37 in register, but only partially, with the surface of the printed conductor 37 partially overlapping each with the surfaces of two adjacent printed conductors 27 and with their intermediate space (partial width overlap = PWO) FIG. 7 to FIG. 12 show further embodiments of the conductor tracks 27, 37 in the representation of Fig. 6. The differences of these embodiments are summarized in Table 1, which also contains comparative values to a conventional film element of FIG. In this case, the measured values indicated therein relate to the superimposition of the first printed conductor 27 and the second printed conductor 37 according to part c) of FIGS. 1 and 7 to 12. Antenna related measurements refer to the antenna formed by the coupling of the first and second traces.

Table 1

An explanation of Table 1 is given below.

The thickness given in line 1 indicates the thickness of the galvanized copper conductor tracks in the unit μιη.

The symmetry indicated in line 2 indicates whether conductor track sections in opposite frame sections are symmetrical to each other (= S) or asymmetrical (= AS).

The frequency indicated in line 3 indicates the resonance frequency f of the antenna of the unit MHz.

The resistance given in line 4 indicates the electrical resistance of the antenna in the unit ohms.

The Q-factor given in line 5 indicates the quality factor of the antenna. The inductance indicated in line 6 indicates the inductance of the antenna in the unit μΗ.

The amplitude given in line 7 indicates the amplitude of the waves in percent. The "waves, top" size specified in line 8 indicates the number of waves (= number of cycles) in the upper frame section.

The size "waves, bottom" specified in line 9 indicates the number of waves (= number of cycles) in the lower frame section.

The "waves, left" size specified in line 10 indicates the number of waves (= number of cycles) in the left frame section.

The size "waves, right" specified in line 11 indicates the number of waves (= number of periods) in the right frame section.

The quantity "rank, waves" indicated in line 12 indicates a ranking with respect to the number of waves of the antennas described, with the antenna with the highest number of waves receiving the highest number.

The size "rank, frequency" given in line 13 gives a ranking in

With respect to the resonance frequency f of the antenna in the unit of MHz, the

Antenna with the highest frequency receives the highest number.

The size "rank, resistance" indicated in row 14 gives a ranking in

Refer to the electrical resistance of the antennas described, with the highest resistance antenna receiving the highest number.

The quantity "rank, Q-factor" given in line 15 indicates a ranking with respect to the figure of merit of the antennas described, with the antenna with the highest figure of merit receiving the highest number.

The length given in line 16 indicates the length of the antenna in percent. The size "rank, length" indicated in line 17 indicates a ranking with respect to the length of the described antennas, with the antenna of the smallest length receiving the highest number. LIST OF REFERENCE NUMBERS

1 foil element

5 frame-shaped area

10 carrier layer

20 first electrically conductive layer

21 base layer

22 reinforcement layer

27 trace

28 contact area

30 second electrically conductive layer

31 base layer

32 reinforcement layer

37 trace

38, 39 contact surface

41, 42 decorative layer

43, 44 Protective varnish layer

51-54 (first to fourth) frame section

61 x axis

62 y-axis

63 z-axis

70 coil

71a-d trace sections

72a-d trace sections

73d trace section, auxiliary structure

74a-d trace sections

80 outer rectangle

81-84 (first to fourth) page

90 inner rectangle

91-94 (first to fourth) page

E xy level

Claims

claims

A film element (1) comprising a dielectric support layer (10) spanning an xy plane (E) of a Cartesian coordinate system having an x-axis (61), a y-axis (62) and a z-axis (63), and at least one electrically conductive layer (20, 30) arranged on the carrier layer (10), in which a frame-shaped region (5) of the film element (1) extends through the surface of a larger, outer rectangle (80), each parallel to the x-axis (61) or y-axis (62) extending sides (81, 82, 83, 84) is formed, from which the surface of a smaller, inner

Rectangles (90) with the same orientation as the outer rectangle (80) is recessed, a conductor track (27, 37) is formed, wherein the

frame-shaped portion (5) is divided into two parallel to the x-axis and two parallel to the y-axis frame sections (51, 52, 53, 54), each of a limiting side (81, 82, 83, 84) of the outer

Rectangles (80) and one of the limiting side (81, 82, 83, 84) of the outer rectangle (80) immediately adjacent and parallel side (91, 92, 93, 94) of the inner rectangle (90) are limited and the

Divide the printed conductor into printed conductor sections (71a to 71d, 72a to 72d, 73d, 74a to 74d),

wherein a mechanical property of the carrier layer (10) along the x-

Axis (61) and the y-axis (62) is different, and

wherein at least one conductor track section (71a to 71d, 72a to 72d, 73d, 74a to 74d), seen parallel to the z-axis (63), extends more than 50% of its length obliquely to the x-axis (61) and the y-axis (62).

Film element (1) according to claim 1,

characterized,

in that the at least one conductor track section (71a to 71d, 72a to 72d, 73d, 74a to 74d) is at least 80%, preferably at least 90%, of its length oblique to the x-axis (61) and the y-axis (62). runs.

Film element (1) according to claim 1 or 2,

characterized,

in that the at least one conductor track section (71a to 71d, 72a to 72d, 73d, 74a to 74d) has a wave or zigzag shape in its oblique portion.

Film element (1) according to one of the preceding claims,

characterized,

in that the y-direction (62) indicates the machine direction of the carrier layer (10) and the x-axis (61) indicates the transversely extending transverse direction of the carrier layer (10).

Film element (1) according to one of the preceding claims,

characterized,

that the mechanical property is a deformation behavior, a

Residual stress or a relaxation behavior is.

Film element (1) according to one of the preceding claims,

characterized,

the length of a first side (91, 92, 93, 94) of the inner rectangle (90) is at least 50%, preferably at least 60%, of the length of a parallel side (81, 82, 83, 84) of the outer rectangle (80 ) and the length of one to the first side (91, 92, 93, 94) of the inner rectangle (90) perpendicular side (91, 92, 93, 94) of the inner rectangle (90) at least 70%, preferably at least 75%, the length of a parallel side (81, 82, 83, 84) of the outer rectangle (80).

Film element (1) according to one of the preceding claims,

characterized,

in that the film element (1) has a first electrically conductive layer (20) in which a first printed conductor (27) is formed in the frame-shaped region (5) of the film element (1), and a second electrically conductive layer (30) in the frame-shaped region (5), a second conductor track (37) is formed, wherein the carrier layer (10) between the first and second electrically conductive layer (20, 30) is arranged, the first and the second conductor track (27, 37 ) are coupled together to form an antenna structure, and at least one track portion (71a to 71d, 72a to 72d, 73d, 74a to 74d) of the first and second tracks (27, 37) exhibits said oblique course.

Film element (1) according to one of the preceding claims,

characterized,

in that the course of the at least one conductor track section (71a to 71d, 72a to 72d, 73d, 74a to 74d) is described by {x; y} coordinate pairs, which are defined by a structuring function F (x or y).

Foil element (1) according to claim 8,

characterized,

the structuring function F (x or y) is designed so that the ratio of a sum of the partial lengths of the at least one

Trace portion (71a to 71d, 72a to 72d, 73d, 74a to 74d), in which the trace portion is oblique to the x-axis (61) and the y-axis (62), to a total length of the at least one trace portion (71a to 71d, 72a to 72d, 73d, 74a to 74d) is maximum. Film element (1) according to claim 8 or 9,

characterized,

the structuring function F (x or y) is a sine function of the form y = F (x) = A ^* sin (2 * TT * f ^* x + φ) or x = F (y) = A * sin (2 * π γ + φ), where A is an amplitude, f is a frequency and φ is a phase angle.

Film element (1) according to one of claims 8 to 10,

characterized,

in that at least two conductor track sections (71a to 71d, 72a to 72d, 73d, 74a to 74d) have the said oblique course, wherein at least one parameter defining the structuring function F (x or y) in the at least two conductor track sections (71a to 71d, 72a to 72d, 73d, 74a to 74d) each have different values. 12. film element (1) according to claim 11,

characterized,

that the substructuring function are defining parameters:

Amplitude, frequency, phase, shape. 13. film element (1) according to one of the preceding claims,

characterized,

in that all conductor track sections (71a, 71c, 72a, 72c, 74a, 74c) running parallel to the x-axis (61) or all conductor track sections (71b, 71d, 72b, 72d, 73d, 74b) extending parallel to the y-axis (62) 74d) show said oblique course.

14. Film element (1) according to one of the preceding claims,

characterized,

in that all the conductor track sections (71a to 71d, 72a to 72d, 73d, 74a to 74d) show said oblique course.

15. film element (1) according to one of the preceding claims, characterized,

in that two conductor track sections (71a to 71d, 72a to 72d, 73d, 74a to 74d) running in two parallel frame sections (51, 52, 53, 54) are parallel to the two parallel frame sections (51, 52, 53, 54) extending axis of symmetry axis or with respect to a

Point symmetry point is formed symmetrically.

Film element (1) according to one of the preceding claims,

characterized,

the length of the at least one conductor track section (71a to 71d, 72a to 72d, 73d, 74a to 74d) is greater by about 0.5 to 30% than the length of a corresponding, not obliquely running track section.

A method of producing a film element (1) comprising the steps of: providing a dielectric support layer (10) having an xy plane (E) of a Cartesian coordinate system having an x-axis (61), a y-axis (62) and a spans the z-axis (63), wherein a mechanical property of the carrier layer (10) along the x-axis (61) and the y-axis (62) is different;

Applying at least one electrically conductive layer (20, 30) to a surface of the carrier layer (10); and

Forming a conductor track (27, 37) in the at least one electrically conductive layer (20, 30) in a frame-shaped region (5) of the film element (1), which extends through the surface of a larger outer rectangle (80) parallel to the x -Axis (61) or y-axis (62) extending sides (81, 82, 83, 84) is formed, from which the surface of a smaller inner rectangle (90) with the same orientation as the outer rectangle (80) is recessed wherein the frame-shaped area (5) in two parallel to the x-axis and two parallel to the y-axis extending

Frame portions (51, 52, 53, 54), each of a limiting side (81, 82, 83, 84) of the outer rectangle (80) and one of the limiting side (81, 82, 83, 84) of the outer Rectangles (80) immediately adjacent and parallel side (91, 92, 93, 94) of the inner rectangle (90) are limited and the conductor in

Conductor track sections (71a to 71d, 72a to 72d, 73d, 74a to 74d), such that at least one track section (71a to 71d, 72a to 72d, 73d, 74a to 74d), parallel to the z-axis (63) seen to extend more than 50% of its length obliquely to the x-axis (61) and the y-axis (62).