US20030118719A1

US20030118719A1 - Method for producing a marking device and apparatus for carrying out said method

Info

Publication number: US20030118719A1
Application number: US10/204,614
Authority: US
Inventors: Jan Morenzin; Daniel Schondelmaier; Wolfgang Eberhardt
Original assignee: Forschungszentrum Juelich GmbH
Current assignee: Forschungszentrum Juelich GmbH
Priority date: 2000-02-22
Filing date: 2001-01-10
Publication date: 2003-06-26
Also published as: AU2001235407A1; DE50115032D1; AU2001225147A1; US20030107832A1; EP1257968A2; WO2001063553A2; DE10008097A1; WO2001063552A2; WO2001063553A3; US20030091867A1; US7055758B2; ATE439648T1; WO2001063554A2; EP1266351A2; EP1266352A2; AU2001242330A1; WO2001063552A3; WO2001063554A3; AR027462A1; AR027463A1

Abstract

The invention relates to a method for producing a marking device (1), according to which a coding coating is applied to the surface of a support (2). The coding coating comprises at least one magnetic base layer (3), at least one magnetic coding layer (5) and a non-magnetic intermediate layer (4) placed therebetween. Said intermediate layer is composed in such a way that areas of non-parallel or anti-parallel magnetic coupling occur. The invention is characterized in that zones on the surface of the support (2) are roughened, before the coding coating is applied. The invention also relates to apparatus for carrying out said method.

Description

The invention relates to a method of producing a marking device in which a coding coating is provided on the surface of a carrier with at least one magnetic base layer and at least one magnetic coding layer as well as at least one regionally applied nonmagnetic intermediate layer between the two, which regionally has such characteristics that zones of nonparallel or antiparallel coupling are produced. The invention relates further to an apparatus for carrying out this method.

In DE 198 52 268 A1= WO 00/30029, a marking device for the application of a coding layer to objects like credit cards, admission cards or the like is disclosed in which, upon the carrier —this can for example be a foil or also a rigid substrate—a coding layer is applied which in the simplest case is comprised of three layers, namely, a magnetic base layer applied to the carrier, a nonmagnetic intermediate layer applied to the base layer, for example with the aid of vapor deposition, and a further magnetic coding layer applied to the intermediate layer. As materials for the base layer and the coding layer, Fe, Co or Ni and their alloys with other elements, especially rare earths or their oxides, come into consideration and for the intermediate layer, for example, Cu, Cr, Ru or Rh. In order to utilize the magnetic intermediate layer coupling effect which is known per se, the intermediate layer has originally such a thickness that a nonparallel, preferably an antiparallel coupling is established while in the remaining regions, the base layer and the coding layer couple in parallel. As a result, the intermediate layer is limited to the regions of the nonparallel coupling or antiparallel coupling so that an especially clear magnetic structuring of the coding will result.

The aforedescribed marking device has the advantage of a highly characteristic magnetic marking property which deviates from the usual magnetic marking with the application of external magnetic fields, especially in that the nonparallel coupling or antiparallel coupling is eliminated under the influence of a saturating magnetic field, the original magnetization state is again restored after the removal of the external magnetic field. The coding is thus not extinguished by the externally-applied magnetic field. In addition, the system can utilize the effect that weakened or even lost magnetic coding, resulting from prolonged storage, for example, can be reactivated in that it can obviate the effect of a saturation magnetic field.

The invention has as its object to provide a method and an apparatus for producing marking devices of the aforedescribed type.

This object is achieved according to the invention in that the surface of the carrier, prior to applying the coding coating, is formed with the zones of different roughness. The invention is based upon the observation that the roughness of the carrier substantially influences the development of the layers thereon and thus also the boundary layers [interfaces] of the intermediate layer. By corresponding adjustment of the roughness distribution, the boundary layers of the intermediate layer are so modified that regions arise in which a nonparallel or antiparallel coupling of the base layer and coding layer are produced and regions in which this coupling does not occur. The desired coding is achieved in the sense of the teaching according to DE 198 52 368.

In the simplest embodiment of the method of the invention, the surface of the carrier, at least in one zone, has a first roughness and at least one zone is provided which has a second roughness. This does not exclude the possibility that zones with more than two roughnesses will be provided in order to make the coding more complex.

The method according to the invention permits the application of the intermediate layer uniformly and over the entire area of the base layer. It allows, however, also for the possibility that the intermediate layer will be applied only regionally and also nonuniformly to the extent that the method is used in accordance with the invention for provided regions of nonparallel or antiparallel coupling on the one hand and regions of parallel coupling on the other.

The generation of different roughnesses can be effected in various ways. Thus the surface carrier can be smooth and/or roughened by means of surface treatment, for example, by etching, ablation, sputtering by means of ion bombardment, etc. In the latter case, the ion bombardment can be effected with the aid of a focused ion beam locally. Alternatively thereto, it is also possible to effect the ion bombardment as a surface treatment and to generated in the region of the carrier a nonhomogeneous electrical charge field which blocks the ions regionally so that the ions only reach the carrier where no blocking electric charge is provided or where an attractive electric charge is provided.

This can be achieved by electrically charging the carrier itself nonhomogeneously. An electrically chargeable substrate can, however, also be nonhomogeneously electrically charged and the carrier load upon this substrate whereby an ion bombardment can be effected on the carrier. Advantageously a carrier foil is drawn off from a supply and is moved continuously with an advancing charging foil and the carrier foil subjected to ion bombardment. Subsequently the carrier foil is separated from the charging foil. The carrier foil can also be withdrawn from supply and then charged and after ion bombardment, can be taken up in a store. Alternatively thereto, it can be provided that the charging foil is circulated through an ion bombardment station and discharged downstream of the ion bombardment station or can have the electric charge thereon homogenized.

Alternatively or in combination therewith is the possibility of regionally coating the surface of the carrier or regionally providing it with coatings of different roughnesses. This can be effected by means of printing, lithography or vapor deposition, for example, sputtering.

To the extent that zones with different roughnesses are produced by coating, a method according to the invention can provide that a carrier foil and a masking foil are advanced together and withdrawn respectively from supplies thereof and that the coating is effected from the masking foil side and the masking foil subsequently separated from the carrier foil when they can be provided with the base layer. The masking foil can be formed with openings already before it is incorporated for supply. Alternatively, however, it is possible to form the masking foil with openings first after its withdrawal from the supply and before it is brought together with the carrier foil, these openings being formed, for example, with the aid of a laser. The aforedescribed method utilizing a masking foil can also be used for the ion bombardment with a surface ion bombardment being applied through the openings in the masking foil to predetermined zones of the carrier as delimited by the openings.

Since the layers can be formed relatively thin so that the described magnetic effects can arise, it has been found to be advantageous to utilize vapor deposition technology to form the layers, i.e. thermal vapor deposition, sputtering or the like. It is advantageous in this connection, when the application of the base layer and the coding layer is carried out under the effect of a magnetic field in order to thereby produce an anisotropy in the individual layers and ensure a suitable magnetization above all in the regions in which no coupling is to be effected. A suitable protective layer can then be provided on the coding layer, the protected layer being formed, for example, from SiC or DLC (diamond-like carbon) this layer being also applied by vapor deposition.

The aforedescribed process can be carried out with an apparatus which is characterized by:

a) a supply store for a carrier foil;

b) a supply store for a masking foil;

c) a surface treatment station for treating the carrier foil;

d) a take-up store for receiving the masking foil;

e) a take-up store for receiving the carrier foil;

f) guide elements and a drive for displacing the carrier foil from the supply store through the surface-treatment station to the take-up store and for displacing the carrier foil and masking foil together upstream of the surface-treatment station and for separating the carrier foil and masking foil upstream of their take-up store.

With the aid of this apparatus, a correspondingly treated carrier foil can be produced which can then be removed from this apparatus and supplied to an apparatus for the application of the base layer, the intermediate layer and the coding layer whereby in the latter apparatus, corresponding coating stations are provided. It can then be advantageous to carry out the surface treatment of the carrier foil and its coating in a single apparatus in that the described apparatus would then be completed with the following apparatus parts:

a) a first coating station for applying a base layer of magnetizable material to the carrier foil;

b) a second coating station for applying an intermediate layer of nonmagnetizable material to the base layer;

c) a third coating station for applying a coating layer of magnetizable material onto the intermediate layer;

d) a take-up store for receiving the marking device;

e) guide elements and a drive for displacing the carrier foil from the supply store through the surface treatment station and the coating station to the take-up store as well as for feeding together the carrier foil and masking foil upstream of the surface-treatment station and for separating the carrier foil and masking foil upstream of the first coating station.

The coating station can be equipped with devices for producing a sufficiently strong magnetic field that an anisotropy and thus a stable magnetization is ensured above all in those regions in which no coupling arises. The devices can be so formed that directly above the carrier foil between the coating station and carrier foil and at the location at which the material meets the carrier foil, a magnetic field of sufficient magnitude to effect anisotropy is produced.

Such an apparatus enables a rapid and economical production of the marking device whereby the carrier foil can, in addition, depending upon the respective application, be labeled appropriately. In this connection, the surface-treatment station and the coating station can also be combined into a station with multiple treatment and/or coating units. In addition, it is possible to provide the surface-treatment station from a plurality of treatment units disposed one after the other and each treatment unit with a supply store for a masking foil and a receiving store for the take-up of the masking foil.

To the extent that the masking foil initially has no openings between the supply store in the masking foil and the joining of the masking foil with the carrier foil, a mask-formation station can be arranged for producing openings in the masking foil, the mask-formation station preferably having a laser-burning unit. In this case, a control device should be provided for varying the position of the laser-burning device.

The surface-treatment station can comprise at least one coating unit, for example in the form of a vapor-deposition unit or a printing unit. Instead of the latter, a device for etching the surface of the carrier foil can be considered.

The surface treatment station also be configured as an ion bombardment station for ion beam treatment of the carrier foil since even with an ion bombardment, the roughness of the surface can be influenced. In the ion bombardment station, two alternatives can be considered. In one case, the station can generate a focused ion beam and a control device can be provided for a targeted control of the ion beam. However, such focussed ion beams can be avoided, i.e. the ion bombardment can be effected as a surface bombardment when an electrically-chargeable carrier foil is displaced through the ion bombardment station and on which a nonhomogeneous electric charge has been provided by a charging device.

A corresponding situation can also be achieved when an electrically-chargeable charging foil is fed through the ion bombardment station which has been provided with a nonhomogeneous electric charge and the feed unit effects a joining of the carrier foil and charging foil upstream of the ion bombardment station. Because of the patterned electrical charge, the ion beam is blocked where the electric charge corresponds to the charge on the ions so that the ion beam only impinges in those regions of the carrier foil where the carrier foil is free from electric charge, or is provided with an opposing electric charge. In carrying out the aforedescribed proposal, a supply store for the charging foil can be provided upstream of the ion bombardment station and a take-up store downstream of the ion bombardment as well as a charging device for applying a patterned electric charge between the supply store and the ion bombardment station. Alternatively thereto it is however also possible to form a charging foil so that it is endless and via the feed device is passed together with the carrier foil through the ion bombardment station whereby a charging device is provided upstream in the travel direction of the bombardment station and a quenching device for quenching the charge or homogenizing. The charge is provided between the ion bombardment station and the charging station. In this embodiment, the charging foil following passage through the ion bombardment station is continuously discharged or provided with a homogeneous charge, then patterned anew with each patterning being individually determined.

The charging foil can be fed over a plurality of rerouting rollers. It is however also possible to tension the charging foil on a support roller which is juxtaposed with the ion bombardment station and over whose roller periphery the carrier foil is guided past the ion bombardment station whereby the roller periphery is chargeable selectively with the electric charge and charging device for applying a patterned electric charge is provided which is the same as the charge on the ion beam, together with a quenching device for homogenizing the electric charge or for discharging the quenching device and the charging device can follow one another in the direction of rotation of the support roller in the region of the roller periphery which is free from the carrier foil.

According to a further feature of the invention, a further coating station can be provided for applying a protective layer on the coding layer. The coating station has advantageously vapor deposition units since with them very thin layers can be produced. For vapor deposition, thermal vapor deposition or sputtering come into consideration.

A supply store or the supply stores and the take-up store or take-up stores are preferably configured as supply rolls or storage rolls. In the coating station and the surface treatment station, carrier rollers can be arranged over those peripheries the carrier foil is fed so that an effective action by the surface treatment station is possible.

The above-mentioned objects are also attained in a method which is characterized in that, in the application of the intermediate layer, at least one mask is used to cover the regions where no intermediate layer formations should be effected.

This can be achieved, for example, by providing a single mask for building up an intermediate layer in the only regions in which a nonparallel or antiparallel coupling is to be produced so that the remaining regions remain free from the intermediate layer. There is, however, also the possibility that two layers can be applied to the carrier and thus one stratum of the intermediate layer without the mask and then at least one further stratum of the intermediate layer regionally utilizing a mask, whereby the two steps can also be carried out a multiplicity of times. In this connection it can also be provided that a first stratum of the intermediate layer can be applied regionally with the use of a first mask and then a second stratum of the intermediate layer applied regionally using a second mask which covers the first stratum, whereby the stratum have different thicknesses. It is always important that in operating with this type of structure, the intermediate layer regions provide nonparallel or antiparallel coupling in certain zones and zones with parallel coupling.

To enable the marking device to be produced in a continuous process, the invention provides that a carrier foil and a masking foil are continuously withdrawn from respective supplies and after applications of the base layer are brought together and then the application of the intermediate layer is applied from the side of the masking foil and the masking foil again directed away from the carrier foil and the latter next provided with the coding layer. The masking foil is provided with openings which can be formed before or after withdrawal of the masking layer from its supply and at the latest, however, before the masking foil is brought together with the carrier foil. The intermediate layer can, as also can the base layer and coding layer, be built up by the vapor deposition technique, especially by means of thermal vapor deposition or sputtering. Here as well a protective layer can be provided on the coding layer, especially by vapor deposition.

A device for carrying out the aforedescribed method can have a configuration similar to the device which is used for the zone-wide coating of the carrier foil. Deviating from this device, the masking foil is here fed through the second coating station so that the intermediate layer is built up on the base layer only in the regions left exposed by the masking foil. In this connection, the second coating station can have a plurality of coating devices disposed one after another and each coating unit can have a supply store for masking foil and take-up store for receiving the masking foil.

Between the supply store for the masking foil and the junction of the masking foil and carrier foil, a mask-forming station can be arranged to produce the openings in the masking foil to the extent the masking foil has not previously been provided with openings. The mask-forming station can have a laser-burning device as well as a control unit for varying the position of the laser-burning device.

The objects are also achieved in a method in which the intermediate layer is applied on a wide surface basis and then at least a partial layer of the intermediate layer is regionally removed. In this method it is possible to apply the intermediate layer initially with a uniform thickness, which thickness is so dimensioned that after application of the coding layer a nonparallel or antiparallel coupling is achieved. By local removal of the intermediate layer, regions are formed which, after application of the coding layer, nonparallel or antiparallel coupling and separately parallel coupling can be obtained so that the desired signature (coding) results. The layer build up can, however, also be so effected that the thicknesses have such dimensions that after applications of the coding layer, a parallel coupling is achieved and only in those regions which have been subjected to local ablation does a nonparallel or antiparallel coupling arise.

The ablation can be effected, for example, by means of chemical etching, whereby the regions which are not to be etched are covered with the aid of lithographic techniques. Instead, an ion sputtering etching, or ion etching can also be carried out which has been found to be especially suitable for a continuous process utilizing a carrier foil.

The last-mentioned method can be carried out by means of an apparatus which is similar to the aforedescribed apparatus with which the carrier foil is regionally roughened by ion bombardment, a difference with respect to this apparatus is that the ion bombardment station is here arranged between the second and third coating stations to regionally remove the intermediate layer. The restriction of the ion bombardment to individual regions can be effected by the same means as described above, for example, utilizing the effect of a focused ion beam or by limiting the effect of a surface ion bombardment, for example, with the aid of a mask, also in the form of a foil, or by the action of a nonhomogeneous electrical charge in the carrier.

The latter can be produced by means of an electrically-chargeable carrier foil or with the previously described charging foil which can be brought together with the carrier foil in the region of the ion bombardment station and supplies a corresponding nonhomogeneous electric field which regionally blocks the ion beam, so that it is not affected for the ablation of the intermediate layer in these regions.

The objects can also be achieved with a method in which the intermediate layer is applied galvanically, i.e. from a coating material in the form of a solution containing metal ions and the application is controlled with respect to location of thickness by a nonhomogeneous electric field. This can be obtained in that the metal ions for the intermediate layer can be blocked regionally by the electric field and regionally drawn to the coating, in such form that regions of the surface to have the intermediate coating will have positive charge and other regions will have negative electrical charge. There where the charge is negative, the positively-charged metal ions will regionally deposit to form the intermediate layer while the positively-charged metal ion will be blocked in the regions of positive charge.

The aforedescribed process is particularly effective for the production of coding coatings. It is, however, also possible to produce regions with different magnetic coupling only after the formation of the coding coating. Such process is characterized in that the coding coating is locally heated to such temperature that the magnetic coupling will be altered and especially a nonparallel or antiparallel coupling will be transformed into a parallel coupling. In this case the intermediate layer is locally distorted with the effect that in those regions at which the heating is effected, a parallel coupling arises.

The aforedescribed method allows, during the fabrication of the coding coating, the production of a uniformly thick intermediate layer which effects a nonparallel or antiparallel coupling. It is suitable especially for continuous coating processes. The local heating is produced preferably by means of a laser.

The aforedescribed method can be carried out especially economically by means of an apparatus which is characterized by:

a) a supply store for a carrier foil;

b) a heating station for locally heating the coding coating;

c) a take-up store for receiving the marking device;

d) guide elements and a drive for feeding the carrier foil from the supply store through the heating station to the take-up store.

With the aid of this apparatus, a base layer, intermediate layer and coding layer on a carrier foil can be locally heated. It is advantageous when the build up of the layers and the local heating is carried out in a single apparatus, in which case, the aforedescribed apparatus is completed with the following apparatus parts:

a) a first coating station for applying a base layer of magnetic material to the carrier foil;

b) a second coating station for applying an intermediate layer of nonmagnetic material to the base layer;

c) a third coating station for applying a coding layer of magnetic material to the intermediate layer:

d) guide elements and a drive for feeding the carrier foil from the supply store through the coating station and through the heating station to the take-up store.

The apparatus has similarities to the aforedescribed apparatus except that a heating station is arranged downstream of the third coating station. To the extent that the heating station is a locally heating laser, a masking of the coding coating can be avoided.

A variation in the magnetic coupling can be achieved, for example, also by means of local ion bombardment. This form of the fabrication of a signature by means of regions of nonparallel coupling or antiparallel coupling on the one hand and parallel coupling on the other is also suitable for continuous production processes of the aforedescribed type. To the extent that the apparatus is involved, the apparatus last described need only have a heating station replaced by an ion bombardment station which is formed in the same manner as in the aforedescribed apparatus where ion bombardment at other locations is effected.

The aforedescribed method and apparatus for producing marking devices according to the invention permit combinations with one another as well. The method and apparatus will then be somewhat more expensive. With the aid of such combined methods and apparatuses, however, still more complex coding can be produced which with random generators can ensure that such coding will be of a singular nature and its reproduction thus practically impossible.

The invention is illustrated in greater detail in the drawing based upon embodiments. It shows: [0060]
FIG. 1 a cross section through a marking device with illustration of the magnetization structure; [0061]
FIG. 2 a cross section through the marking device according to FIG. 1 with the magnetization in the saturation range; [0062]
FIG. 3 a graph from which the dependence of antiparallel coupling strength upon the layer thickness of the intermediate layer is demonstrated; [0063]
FIG. 4 a device for applying the intermediate layer by the masking technique and [0064]
FIG. 5 a device for applying an intermediate layer and for regional ablation by means of ion bombardment.[0065]
The [0066] marking device 1 shown in FIGS. 1 and 2 comprises a carrier layer 2, for example of Si/SiO₂. It can have an optional thickness suitable for the respective purpose. On the carrier layer 3, a permanently magnetic base layer 3 is applied, for example, of cobalt in a thickness of 40 nm. An intermediate layer 4 is applied selectively to this base layer 3, i.e. regionally, and can be comprised of copper in a thickness of 0.8 nm. On the regions without the intermediate layer and with the intermediate layer 4, a coding layer 5 is applied, for example of Co in a thickness of about 25 nm and can be coated on its upper surface with a protective layer 6, for example, of 50 nm thick Cu layer or a polymeric protective lacquer like, for example, 10 μm PMMA.
The arrows show the directions and strengths of the magnetizations of the [0067] base layer 3 and coating layer 5, 0 quantitatively. The direction of the magnetization, however, is rotated by 90° however for convenience of illustration. With the here described material combination Co/Cu/Co—as also with most other material combinations which come into consideration—the directions of magnetization lie in the planes of the base layers 3 10 and coating layer 5 and thus are partly parallel and partly antiparallel.
From FIG. 1 it is to be noted that the [0068] base layer 3 is magnetized uniformly over its area. The coating layer 5 is also magnetized when the saturation magnetization because of the small 15 thicknesses, is less than that in the base layer 3. In the regions in which no intermediate layer is provided, the magnetization in the coding layer 5 is, parallel and unidirectional [with that of the base layer 3]. Where the intermediate layer 4 is provided, an antiparallel coupling of the magnetization is effective, i.e. the magnetization of the base layer 3 and the coding layer 5 are oppositely directed and thus antiparallel. Above the marking device there is shown in a box the strength of the resultant magnetic field by arrows and over [this box] the corresponding signal which can be read [from the marking device] in the form of a graph. It is to be noted that the magnetization of the base layer 3 in the regions in which no intermediate layer 4 is provided is reinforced by the coding layer 5. There, where an intermediate layer 4 is applied, is however a weakening of the resultant magnetic field of the overall layer arrangement as a consequence of the antiparallel coupling. As a consequence, a coding structure arises with different resultant field strengths at the surface and which can be detected by suitable sensors and analyzed.
FIG. 2 shows the state of the marking device in an external magnetic field in the saturation range. It is to be noted that the antiparallel coupling is destroyed so that now even the regions of the [0069] coding layer 5 which are separated by an intermediate layer 4 from the base layer 3, as well as the neighboring regions without separation by an intermediate layer, have parallel and commonly-directed magnetizations. Thus all regions are uniformly magnetized, i.e. variations of the magnetic signals disappears. A coding is no longer in effect. Upon removal of the external magnetic field and thus restoration of the remanence state, however, spontaneously that restores the condition and visible from FIG. 1, a parallel and antiparallel coupling. As a result, the marking device 1 can be differentiated from other marking devices which can be produced with conventional magnetization techniques, and in which the coding can be extinguished by the application of an external magnetic field.
In the graph according to FIG. 3, the thickness of the [0070] intermediate layer 4 is given along the abscissa and the antiferromagnetic coupling strength along the ordinate, and indeed, for the example in which the base layer 3 and coating layer 5 are comprised of cobalt and each has a thickness of 40 nm. It is to be noted that the thickness of the antiferromagnetic coupling varies with the thickness of the intermediate layer. The highest coupling strength is reached by about 0.8 nm. Between the extremes there are regions in which no antiparallel coupling arises but a coupling of less than 180°, e.g. about 90°, until there is a parallel ferromagnetic coupling. Even then regions can be used in that a desired magnetization structure and therefore coded structure with high complexity can be obtained so that then not only—as in the example according to FIG. 1, two different overall magnetizations prevail but a plurality or multiplicity of different magnetizations.
A marking device with the layer structure according to FIGS. 1 and 2 can be produced with the aid of an [0071] apparatus 11 which —although not illustrated here in further detail—is arranged in a housing maintained under high vacuum. The apparatus 11 has three vaporization stations 12, 13, 14 with each vaporization station 12, 13, 14 having a support roll 15, 16, 17 which in its lower regions which are flanked by rerouting rolls 18, 19 or 20, 21 or 22, 23. Above the first and second support rolls 15, 16 are respective vaporization devices 24,25. The third support roll 17 has two vaporization devices 26, 27 juxtaposed therewith.
Ahead of the [0072] first vaporization station 12 there is a supply roll 28 on which a carrier foil 29 has been rolled up. Between the first and second vaporization stations 12 and 13, a further supply roll 30 is arranged on which a masking foil 31 is rolled up. The supply roll 30 has juxtaposed therewith a laser device 33 with the aid of which opening, for example designated at 34—can be burned into the masking foil 31.
During the coating the [0073] carrier foil 29 is withdrawn from its supply roll 28 and runs around the first rerouting roll 18 and is entrained by the support roll 15. It travels, therefore, through the first coating station 12 where a base layer 32 is vapor deposited thereon. Then the carrier foil passes under the rerouting roll 19 and joins with the masking foil 32 upstream of the rerouting roll 20. Both are entrained by the support roll 16 whereby the masking foil 31 lies on the carrier foil 29 from the outer side. Previously in the masking foil 31, with the aid of laser device 33, a pattern of openings—for example designed at 34 —are burned. By corresponding control of the laser beam generated by the laser device 33—there can also be a plurality of laser beams—, for example with the aid of a random generator, a pattern which continuously changes can be produces the material for intermediate layer 35 by sputtering it onto the foil. Because of the partial covering by the masking foil 31, the material of the base layer 32 can only be reached in regions of the openings 34 in the masking foil 31 so that the intermediate layer 35 is only formed there.
After passing over the rerouting [0074] roller 21, the masking foil 31 is led upwardly away from the carrier foil 29 and rolled up in a storage roll 36. The carrier foil 29 has on its upper side not here shown in greater detail—a pattern of the base layer 30 and intermediate layer 35 corresponding to the openings 34 in the masking foil 31.
The [0075] carrier foil 29 runs horizontally to the next rerouting roll 22 and then passes around the support roll 17. With the aid of the two vapor deposition devices 26, 27, base layer 30 and intermediate layer 35 are provided with a coding layer 37 of ferromagnetic material and a protective layer 38, for example, of diamond-like carbon or silicon carbide. In the regions in which no intermediate layer 35 is provided, the base layer 30 and coding layer 37 couple in parallel. There where intermediate layer 35 is provided, the coupling is antiparallel because the intermediate layer 35 in the vaporization station 13 has received such thickness that it establishes the antiparallel coupling.
Then the [0076] carrier foil 29, provided with the coding coating of base layer 30, intermediate layer 35, outer layer 37 and protective layer 38, is looped around the rerouting roller 23 and wound up on the storage roll 39. It can then be packaged corresponding to its respective use.
FIG. 5 shows a [0077] further apparatus 41 for producing a marking device according to FIGS. 1 and 2. This device as well is enclosed in a high vacuum housing. It comprises in sequence in the direction of travel a first vapor deposition station 42, an ion bombardment station 43 and second vapor deposition station 44. The stations 42, 43, 44 have support rolls 45, 46, 47 which are flanked in lower regions respectively by pairs of rerouting rollers 48, 49 or 50, 51 or 52, 53.
The first vapor deposition station [0078] 42 has two evaporating units above the support roll 45. The second vapor deposition station 44 also has two vapor deposition devices 56, 57 arranged next to one another in the upper part. In the ion bombardment station 43, above the support roll 46 an ion charging device 58 is provided. Below the support roll 46 and between the associated rerouting rollers 50, 51 is a charge-distributing device 59 provided on the left side with which the support roll 46 can be provided with regions of positive electrical charge and/or reasons of negative electrical charge. This can be achieved, for example, in accordance with the principles of a laser printer by initially applying a homogeneous charge which is removed in zones by local exposure to light of the surface of the support roll 46. At the right-hand side from the charge-distributing device 59, a quenching device 60 is arranged which results in complete discharge of the surface of the support roll 46 or leaves the latter with a homogeneous electric charge.
On a [0079] supply roll 61, a carrier foil 42 is wound up. In operation, the carrier foil 62 is drawn off the supply roll 61 and passes around the first rerouting roller 48 onto the periphery of the first support roll 45 with which it is entrained. It then travels to the first vaporization unit and there has a wide area coating sputtered onto it as a base layer 63. By means of the second vapor deposition device 55, an intermediate layer 54 of nonmagnetic material is sputtered onto the full surface of the base layer 63. The thus equipped carrier foil 62 passes around subsequent rerouting rollers 49 and 50 and travels then onto the periphery of the second support roll 46 and loops around the latter. It thus passes the ion bombardment device 58 which causes ions to impinge on the intermediate layer 54 over the entire area thereof. Because of the charge distribution on the surface of the support roll 46 which has been generated previously by the charge distribution device 59, the surface of the intermediate layer 64 has regions which block the ion impingement and/or draw the ions to it. For those regions with attractive potential, the intermediate layer 64 is ablated so that only parts of the intermediate layer 64 remain. The support roll 46 is homogeneous upon continuing rotation before it reaches the quenching device 60 and is thus either completely discharged or provided with a homogeneous charge so that the charging unit 59 can again charge the support roll 46 with a new distribution pattern.
After passing around the rerouting [0080] rollers 51, 52 the carrier foil 62 passes into the second vapor deposition station 44 in which it again is fed over the periphery of the support roll 47. There the pattern of base layer 63 and intermediate layer 64 is provided with a coding layer 65 with the aid of the vapor deposition unit 56, the coding layer consisting of ferromagnetic material, and then with a protective layer 66 by means of the further vapor deposition unit 57. In the regions without the intermediate layer, parallel coupling between the base layer 63 and coding layer 65 is established while there, where an intermediate layer 64 is provided, antiparallel coupling arises, since the intermediate layer 64 was applied in the first vapor deposition station 42 in such thickness that such coupling would result.
After passing through the [0081] second vaporization station 44, the carrier foil 61 provided with the coding coating is wound up in a storage roll 47 after passing the last rerouting roller 53. It can then be separated into single sheets.

Claims

1. A method of producing a marking device (1) in which the surface of a carrier (2) has coding coating applied thereto with at least one magnetic base layer (3) and at least a magnetic coding layer (5) as well as with a nonmagnetic intermediate layer (4) arranged between the two, which has such properties that regions of nonparallel or antiparallel coupling are provided, characterized in that the surface of the carrier (2) before applying the coding coating, is formed with zones of different roughness.

2. The method according to claim 1, characterized in that the surface of the carrier (2) has at least one region which has a first roughness and at least one region which has a second roughness.

3. The method according to claim 1 or 2, characterized in that the intermediate layer (4) is uniformly applied.

4. The method according to claim 1 or 2, characterized in that the intermediate layer (4) is applied over the entire area of the base layer (3).

5. The method according to claim 1 to 4, characterized in that the surface of the carrier (2) is coated using the lithographic technique regionally.

6. The method according to claim 1 to 4, characterized in that the surface of the carrier (2) is regionally smooth and/or roughened by means of surface treatment.

7. The method according to claim 6, characterized in that the surface of the carrier (2) is regionally roughened y means of etching and/or ion bombardment.

8. The method according to claim 7, characterized in that the ion bombardment is effected with the aid of a focused laser beam.

9. The method according to claim 7, characterized in that the ion bombardment is effected arealy and a nonhomogeneous electric charge field is established in the region of the carrier (2).

10. The method according to claim 9, characterized in that an electrically chargeable carrier is nonhomogeneously electrically charged prior to the ion bombardment.

11. The method according to claim 9, characterized in that an electrically chargeable substrate is nonhomogeneously electrically charged and the carrier is led on to this substrate and the ion bombardment is effected on the carrier.

12. The method according to claim 11, characterized in that a carrier foil is withdrawn from a supply and brought together with a continuously moving charging foil and the carrier foil is treated with ion bombardment.

13. The method according to claim 12, characterized in that the carrier foil and charging foil are separated after the ionic bombardment.

14. The method according to claim 12 or 13, characterized in that the charging foil is withdrawn from a supply and then charged and is afterward taken up in a store.

15. The method according to claim 12 or 13, characterized in that the charging foil is fed in a circulation through the ion bombardment station and the charging foil is charged upstream of the ion bombardment station and is discharged downstream of the ion bombardment station or the electric charge is homogenized.

16. The method according to claim 1 to 4, characterized in that the surface of the carrier (2) is regionally coated or regionally provided with different roughness coatings.

17. The method according to claim 16i characterized in that the surface of the carrier (2) is printed.

18. The method according to claim 16, characterized in that the surface of the carrier (2) is regionally coated by vapor deposition.

19. The method according to claim 6 or to one of claims 16 to 18, characterized in that a carrier foil and a masking foil are continuously withdrawn from respective stores and are brought together and that then the application of the coating or the ion bombardment is effected from the side of the masking foil and the masking foil is again separated form the carrier foil and the latter is then provided with the base layer.

20. The method according to claim 19, characterized in that the masking foil after withdrawal from the supply and before being brought together with the carrier foil is formed with openings.

21. The method according to one of claims 1 to 20, characterized in that the base layer (3), the intermediate layer (4) and the coding layer (5) are vapor deposited.

22. The method according to one of claims 1 to 21, characterized in that the application of the base layer (3) and of the coding layer (5) is carried out under the effect of a magnetic field.

23. The method according to one of claims 1 to 22, characterized in that a protective layer is applied, especially by vapor deposition to the coding layer.

24. An apparatus for carrying out the method according to one of claims 1 to 23 characterized by:

a) a supply store for a carrier foil;

b) a supply store for a masking foil;

c) a surface treatment station for the treatment of the carrier foil;

d) a take-up store for the receipt of the making foil;

e) a take-up store for the receipt of the carrier foil. [sic]

f) feed devices and a drive for feeding the carrier foil from the supply store through the surface treatment station to the take-up store as well as for joining together the carrier foil and masking foil upstream of their take-up stores.

25. The apparatus according to claim 24, characterized by

b) a second coating station for applying an intermediate layer of nonmagnetizable material on the base layer;

c) a third coating station for applying a coating layer of magnetizable material on the intermediate layer;

d) a take-up store for receiving the marking device;

e) feed devices and a drive for feeding the carrier foil from the supply store through the treatment station and the coating stations to the take-up store and also for joining the carrier foil and masking foil upstream of the surface treatment station and for separating the carrier foil and masking foil upstream of the first coating station.

26. The apparatus according to claim 24 or 25, characterized in that the surface treatment station has a plurality of treatment devices disposed one behind the other and each treatment device has a supply store for a masking foil and a take-up store for receiving the masking foil.

27. The apparatus according to one of claims 24 to 26, characterized in that between the supply store for the masking foil and the joining of the masking foil and carrier foil a mask-forming station is arranged for forming openings in the masking foil.

28. The apparatus according to claim 27, characterized in that the mask-forming station has a laser-burning device.

29. The apparatus according to claim 28, characterized in that the mask-forming station has a control device for variable position control of the laser-burning device.

30. The apparatus according to one of claims 24 to 29, characterized in that the surface-treatment station has at least one coating device.

31. The apparatus according to claim 30, characterized in that the coating device is configured as a vapor-deposition device.

32. The apparatus according to claim 31, characterized in that the coating device is formed as a printing unit.

33. The apparatus according to claims 22 to 29, characterized in that the surface-treatment station has a unit for etching the surface of the carrier foil.

34. The apparatus according to claims 24 to 32, characterized in that the surface-treatment station is configured as an ion-bombardment station.

35. The apparatus for carrying out the method according to claim 7, characterized by:

a) a supply store for a carrier foil;

b) an ion-bombardment station for the ion beam impacting of the carrier foil;

c) a take-up store for the carrier foil;

d) guide elements and a drive for feeding the carrier foil from the supply store through the ion-bombardment station to the take-up store.

36. The apparatus according to claim 35, characterized by:

c) a third coating station for applying a coding layer of magnetizable material to the intermediate layer;

d) a take-up store for the marking device;

e) guide elements and a drive for feeding the carrier foil from the supply store through the ion bombardment station and the coating stations to the take-up store.

37. The apparatus according to claim 35 or 36, characterized in that the ion-bombardment station generates a focused ion beam and is provided with a control device for the targeted control of the ion beam.

38. The apparatus according to claim 35 or 36, characterized in that the ion-bombardment station has an electrically-chargeable carrier foil guided through it and which is provided with a nonhomogeneous electric charge by a charging device.

39. The apparatus according to claim 35 or 36, characterized in that an electrically-chargeable charging foil is fed through the ion-bombardment station and has been provided with a nonhomogeneous electric charge by a charging device and that the feed elements effect a bringing together of the carrier foil and the charging foil upstream of the ion-bombardment station.

40. The apparatus according to claim 39, characterized in that a supply store is provided for the charging foil upstream of the ion-bombardment station and a take-up store is provided downstream of the ion-bombardment station and a charging device for the nonhomogeneous charging of the charging foil is provided between the supply store and the ion-bombardment station.

41. The apparatus according to claim 39, characterized in that the charging foil is configured as endless and by the feed elements is fed together with the carrier foil through the ion-bombardment station, and that the charge device is provided upstream of the ion-bombardment station in the travel direction of the carrier foil, and a quenching device is provided between the ion-bombardment station and the charging device for discharging or homogenizing the electric charge.

42. The apparatus according to claim 39, characterized in that the charging foil is stretched on a support roll which is juxtaposed with the ion-bombardment station.

43. The apparatus according to claim 35 or 36, characterized in that the ion-bombardment station is juxtaposed with a support roll over the roll periphery of which the carrier foil is passed through the ion-bombardment station, and that the roll periphery is chargeable with an electric charge, whereby a charging device is provided for charging the roll periphery which charge is the same as the charge of the ion beam, and a quenching device is provided for discharging or homogenizing the roll periphery.

44. The apparatus according to claim 43, characterized in that the roll periphery has a coating chargeable with electric charge.

45. The apparatus according to one of claims 24 to 44, characterized in that the quenching device and the charging device are provided after one another in the direction of rotation of the support roll in the region of the roll periphery which is free from the carrier foil.

46. The apparatus according to one of claims 25 to 45, characterized in that a further coating station is provided for applying a protective layer to the coding layer.

47. The apparatus according to one of claims 25 to 46, characterized in that the coating stations have vapor deposition devices.

48. The apparatus according to one of claims 24 to 47, characterized in that the supply store or the supply stores and the take-up store or the take-up stores are configured as supply rolls or storage rolls.

49. The apparatus according to one of claims 25 to 48, characterized in that the surface-treatment station or the ion-embardment station as well as the coating station have carrier rollers over whose roll periphery the carrier foil is guided.

50. A method of producing a marking device in which, upon the surface of a carrier (29) a coding coating with at least one magnetic base layer (30) and at least one magnetic coding layer (37) as well as an intermediate layer (35) disposed therebetween, is applied, which has such a characteristic that it provides regions of nonparallel or antiparallel coupling, characterized in that in the application of the intermediate layer (35) at least one mask (32) is used for covering the regions at which no intermediate layer formation is to be effected.

51. The method according to claim 50, characterized in that a single mask (32) is used to build up the intermediate layer (35) only in the regions in which a nonparallel or antiparallel coupling is to be produced.

52. The method according to claim 51, characterized in that on the carrier two layers are applied including a layer without a mask and a layer which is applied regionally with the use of a mask.

53. The method according to claim 50, characterized in that to build up the intermediate layer a first layer is applied regionally with the use of a first mask and then a second layer is applied regionally with the use of a second mask which covers the first layer, whereby the thickness of one of the two layers is such that there no nonparallel or antiparallel coupling arises.

54. The method according to one of claims 50 to 53, characterized in that a carrier foil (30) and at least one masking foil (32) are drawn continuously from respective supplies (28, 31) and after application of the base layer (30) are brought together and then after application of the intermediate layer (35) from the side of the masking foil (32) and the masking foil or foils (32) are then again separated from the carrier foil (29) and the latter then provided with the coding layer (37).

55. The method according to claim 54, characterized in that the masking foil (32) after withdrawal from the supply (31) and before being brought together with the carrier foil (20) is. provided with openings (34).

56. The method according to one of claims 50 to 55, characterized in that the base layer (30), the intermediate layer (35) and the coding layer (37) are applied by means of vapor deposition.

57. The method according to one of claims 50 to 56, characterized in that the application of the base layer (30) and the coding layer (37) are effected under the influence of a magnetic field.

58. The method according to one of claims 50 to 57, characterized in that a protective layer is applied to the coding layer, especially by vapor deposition.

59. An apparatus for carrying out the method according to one of claims 50 to 58, characterized by:

a) a supply store (29) for a carrier foil (29);

b) a first coating station (12) for applying a base layer (32) of magnetic material;

c) a supply store (30) for a masking foil (31);

d) a second coating station (13) for applying an intermediate layer (35) of nonmagnetic material to the base layer (32) in the regions left free from the masking foil (31);

e) a take-up store (36) for receiving the masking foil (31);

f) a third coating station (14) for applying a coding layer (37) of magnetic material to the pattern of the base layer (32) and the intermediate layer (35);

g) a take-up store (39) for receiving a marking device;

h) feed elements (15 to 23) and a drive for feeding the carrier foil (29) from the supply store (28) through the coating stations (12, 13, 14) to the take-up store (39) and for feeding the carrier foil (29) and the masking foil or foils (31) together between the first and second coating stations (12, 13) and for separating the carrier foil (29) and the masking foil (31) between second and third coating stations (13, 14).

60. The apparatus according to claim 59, characterized in that the second coating station has a plurality of coating devices arranged one after the other and each coating device is associated with a supply store for a masking foil and a take-up store for receiving the masking foil.

61. The apparatus according to claim 59 or 60, characterized in that between supply store (30) for the masking foil (31) and the joining of the masking foil (31) and the carrier foil (29), a mask-forming station (33) is located for forming openings (34) in the masking foil (31).

62. The apparatus according to claim 61, characterized in that the mask-forming station has a laser-burning station (33).

63. The apparatus according to claim 62, characterized in that the mask-forming station (33) has a control device for varying the position of the laser-burning device.

64. The apparatus according to claims 59 to 63, characterized in that a further coating station (27) is provided for applying a protective layer (38) to the intermediate layer (35).

65. The apparatus according to one of claims 59 to 64, characterized in that the coating stations (12, 13, 14) have vapor-deposition units.

66. The apparatus according to one of claims 59 to 65, characterized in that the supply store and the take-up store are configured as supply rolls (28, 31) or storage rolls (36, 39).

67. The apparatus according to one of claims 59 to 66, characterized in that the coating stations (12, 13) have support rolls (15, 16, 17) over whose roll peripheries the carrier foil (29) is guided.

68. A method of making a marking device in which a coding coating with at least one magnetic base layer (63) and at least one magnetic coding layer (65) as well as a nonmagnetic intermediate layer (64) between them is applied to the surface of a carrier (62) and which has such a characteristic that it has regions of nonparallel or antiparallel coupling, characterized in that the intermediate layer (64) is initially applied over the entire area and then at least a part of the intermediate layer (64) is regionally removed.

69. The method according to claims 68, characterized in that the intermediate layer (64) is applied with a uniform thickness.

70. The method according to claim 68 or 69, characterized in that the removal is effected by etching.

71. The method according to one of claims 68 to 70, characterized in that for the removal a lithographic process is used.

72. The method according to claim 68 or 69, characterized in that the removal is effected by means of ion bombardment.

73. The method according to claim 72, characterized in that the ion bombardment is effected with the aid of a focused ion beam.

74. The method according to claim 72, characterized in that the ion bombardment is effected over the entire area and in the region of the carrier (62) a nonhomogeneous electrical charge field is generated.

75. The method according to claim 74, characterized in that an electrically-chargeable carrier is charged electrically nonhomogeneously prior to the ion bombardment.

76. The method according to claim 74, characterized in that an electrically-chargeable substrate (46) is nonhomogeneously charged and that the carrier (62) is laid upon this substrate (46) and the ion bombardment (58) is effected on the carrier (62).

77. The method according to claim 76, characterized in that a carrier foil is withdrawn from a supply and is fed together with a continuously-moving charging foil as substrate and both are subjected to ion bombardment.

78. The method according to claim 77, characterized in that the carrier foil and the charging foil are separated downstream of the ion bombardment.

79. The method according to claim 77 or 78, characterized in that the carrier foil is drawn from a supply, is then electrically charged and after the ion bombardment is taken up in a store.

80. The method according to claim 77 or 78, characterized in that the charging foil is displaced in a circulating path through an ion bombardment station and that the charging foil upstream of the ion-bombardment station is electrically charged and downstream of the ion bombardment station is discharged or has its electric charge homogenized.

81. The method according to claim 73 or 74, characterized in that a carrier foil and a masking foil are continuously drawn from respective supplies and brought together and that then the ion bombardment is effected from the side of the masking foil and the masking foil, again separated from the carrier foil, is again separated from the carrier foil and the latter is then provided with the coding layer.

82. The method according to claim 81, characterized in that the masking foil, upon withdrawal from the supply and before being brought together with the carrier foil, is provided with openings.

83. The method according to one of claims 68 to 82, characterized in that the base layer (63) the intermediate layer (64) and the coding layer (65) are vapor deposited.

84. The method according to one of claims 68 to 83, characterized in that the application of the base layer (63) and of the coding layer (65) are effected under the influence of a magnetic field.

85. The method according to one of claims 68 to 84, characterized in that the coding layer (65) has a protective layer (66) applied thereto, especially by vapor deposition.

86. An apparatus for carrying out the method according to one of claims 68 to 85, characterized by:

a) a supply store (60) for a carrier foil (61);

b) a first coating station (54) for applying a base layer (63) of magnetic material;

c) a second coating station (5) [sic] for applying an intermediate layer (64) of nonmagnetic material to the base layer (63);

d) an ion bombardment station (43) for the regional ion bombardment of the intermediate layer (64);

e) a third coating station (44) for applying a coding layer (65) of magnetizable material to the combination of intermediate layer (64) and the base layer (63Y;

f) a take-up store (67) for the marking device;

g) guide elements (45 to 53) and a drive for feeding the carrier foil (62) from the supply store (61) through the first and second coating stations (54, 55), the ion-bombardment station (43) and the third coating station (44) to the take-up store (67).

87. The apparatus according to claim 86, characterized in that the ion-bombardment station generates a focused ion beam and a control device is provided for the targeted control of the ion beam.

88. The apparatus according to claim 86 or 87, characterized in that the ion-bombardment station has an electrically-chargeable carrier foil fed therethrough and which is provided with a nonhomogeneous electric charge by a charging device.

89. The apparatus according to claim 86 or 87, characterized in that the ion-bombardment station has an electrically-chargeable charging foil passed therethrough and provided with a nonhomogeneous electric charge and that the feed elements effect a joining of the carrier foil and charging foil upstream of the ion-bombardment-station.

90. The apparatus according to claim 89, characterized in that a supply store is provided for the charging foil upstream of the ion-bombardment station and a take-up store is provided downstream of the ion-bombardment station and a charging device for the nonhomogeneous charging of the charging foil is provided between the supply store and the ion-bombardment station.

91. The apparatus according to claim 89, characterized in that the charging foil is formed as an endless member and is guided via the guide elements together with the carrier foil through the ion-bombardment station and that a charging device in the travel direction of the carrier foil is provided upstream of the ion-bombardment station and a quenching device for discharging the electric charge or homogenizing the electric charge is provided downstream of the ion-bombardment station.

92. The apparatus according to claim 91, characterized in that the charging foil is spanned on a support roller which s juxtaposed with the ion-bombardment station.

93. The apparatus according to claim 86 or 87, characterized in that the ion-bombardment station is juxtaposed with a support roll over whose roll periphery the carrier foil (61) is displaced past the ion-bombardment station (43) and that the roll periphery is chargeable with an electric charge whereby the charging device (59) is provided to charge the roll periphery and which is the same charge as the charge of the ion beam, and a quenching device (60) is provided to discharge the roll periphery or homogenize the roll periphery.

94. The apparatus according to claim 93, characterized in that the quenching device (59) and a writing device (58) follow one another in the rotation direction of the support roll (59) and are arranged in the region of the roll periphery which is free from the carrier foil (61).

95. The apparatus according to claim 93 or 94, characterized in that the roll periphery has a coating chargeable with an electric charge.1

96. The apparatus according to claim 86 or 87, characterized in that a masking foil is passed through the ion-bombardment station and that the guide elements effect a joining of the carrier foil and masking foil upstream of the ion-bombardment station in such manner that the ion bombardment is effected from the side of the masking foil, and that the guide elements separate the carrier foil and the masking foil after the ion-bombardment station.

97. The apparatus according to claim 96, characterized in that between a supply store for the masking foil and the joining of the masking foil and the carrier foil, a mask-forming station is arranged to produce openings in the masking foil.

98. The apparatus according to claim 97, characterized in that the mask-forming station has a laser-burning unit.

99. The apparatus according to claim 98, characterized in that the mask-forming station has a control device for varying the position of the laser-burning device.

100. The apparatus according to one of claims 86 to 99, characterized in that a further coating station (57) is provided for applying a protective layer (66) to the coding layer (65).

101. The apparatus according to one of claims 86 to 100, characterized in that the coating stations (42, 44) have vapor-deposition devices (54, 55).

102. The apparatus according to one of claims 86 to 101, characterized in that the supply store is configured as a supply roll (60) and the take-up store has a storage roll (66).

103. The apparatus according to one of claims 86 to 102, characterized in that the coating stations (42, 44) and the ion-bombardment station (43) have carrier rollers (45, 46, 47) over the roll peripheries of which the carrier foil (61) is guided.

104. A method of producing a marking device in which on a surface of a carrier, a coding coating has at least one magnetic base layer and at least one magnetic coding layer as well as a nonmagnetic intermediate layer between them, is provided and which has such a characteristic that regions of nonparallel or antiparallel coupling are provided, characterized in that the intermediate layer is galvanically applied and the application is controlled with respect to place and thickness by a nonhomogeneous electric field.

105. The method according to claim 104, characterized in that in the galvanic application of the intermediate layer the surface to receive the layer has regions of positive electric charge and/or regions of negative electric charge produced thereon.

106. The method of producing a marking device in which, on the surface of a carrier, a coding coating is applied with at least one magnetic base layer, at least one magnetic coding layer and a nonmagnetic intermediate layer between them, and which has a characteristic such that regions of nonparallel or antiparallel coupling are produced, characterized in that the coding coating after it is produced is locally heated to such a temperature that there the magnetic coupling is altered.

107. The method according to claim 106, characterized in that in the coding coating is locally heated to such a temperature that there a nonparallel or antiparallel coupling is converted into a parallel coupling.

108. The method according to claim 106 or 107, characterized in that in the production of the coding coating a uniformly thick intermediate layer is produced which effects a nonparallel or antiparallel coupling.

109. The method according to one of claims 106 to 108, characterized in that in the base layer, the intermediate layer and the coding layer are vapor deposited.

110. The method according to one of claims 106 to 109, characterized in that the application of the base layer and of the coating layer are effected under the influence of a magnetic field.

111. The method according to one of claims 106 to 110, characterized in that with the intermediate layer, a protective layer is applied especially by vapor deposition.

112. The apparatus for carrying out the method according to one of claims 106 to 111, characterized by:

a) a supply store for a carrier foil;

b) a heating station for locally heating the coding coating;

c) a take-up store for receiving the marking device;

113. The apparatus according to claim 112, characterized by:

c) a third coating station for applying a coding layer of magnetizable material on the intermediate layer;

114. The apparatus according to claim 112 or 113, characterized in that the heating station has a laser.

115. The apparatus claim 113 or 114, characterized in that a further coating station is provided for applying a protective layer on the coding layer.

116. The apparatus according to one of claims 113 to 115, characterized in that the coating stations have vapor-deposition devices.

117. The apparatus according to one of claims 112 to 116, characterized in that the supply store is formed as a supply roll and the take-up store has a storage roll.

118. The apparatus according to one of claims 113 to 117, characterized in that the coating stations and the heating station have carrier rolls over whose roll peripheries the carrier foil is guided.

119. The method of making a marking device in which a coding coating is provided on the surface of a carrier and has at least one magnetic base layer, at least one magnetic coding layer and a nonmagnetic intermediate layer arranged between the two and which has such characteristics that regions of nonparallel or antiparallel coupling are produced, characterized in that the coding coating after its production is locally subjected to ion bombardment and that there the magnetic coupling is altered.

120. The method according to claim 119, characterized in that the coding coating after production is locally treated with ion bombardment so that there a nonparallel or antiparallel coupling is transformed into a parallel coupling.

121. The method according to claim 119 or 120, characterized in that in the production a uniform thickness intermediate layer is produced which forms a nonparallel or antiparallel coupling.

122. The method according to one of claims 119 to 121, characterized in that the ion bombardment is effected with the aid of a focused ion beam.

123. The method according to one of claims 119 to 121, characterized in that the ion bombardment is effected over an area and in the region of the carrier a nonhomogeneous electric charge field is produced.

124. The method according to claim 123, characterized in that an electrically-chargeable carrier prior to the ion bombardment is nonhomogeneously electrically charged.

125. The method according to claim 123, characterized in that an electrically-chargeable substrate is charged nonhomogenously electrically and that the carrier is placed upon this substrate and the ion bombardment is effected on the combination of the substrate and the carrier.

126. The method according to claim 125, characterized in that a carrier foil is drawn from a first supply and after the coating is brought together with a continuously moved charging foil has an underlay and both are subjected to ion bombardment.

127. The method according to claim 126, characterized in that the carrier foil and the charging foil are separated after the ion bombardment.

128. The method according to claim 126 or 127, characterized in that the charging foil is withdrawn from a supply and is then charged and after the ion bombardment is taken up in a store.

129. The method according to claim 126 or 127, characterized in that a charging foil is displaced as a substrate in a circulating path through an ion bombardment station and the charging foil is charged upstream of the ion-bombardment station and downstream of the ion-bombardment station is discharged or has its electric charge homogenized.

130. The method according to claim 119 to 121, characterized in that a carrier foil and a masking foil are continuously withdrawn from respective supplies and brought together and that then the ion bombardment is effected from the sides of the masking foil and the masking foil is again separated from the carrier foil.

131. The apparatus [sic] according to claim 130, characterized in that the masking foil after being withdrawn from the supply and before being brought together with the carrier foil is provided with openings.

132. The method according to one of claims 119 to 131, characterized in that the base layer, the intermediate layer and the coding layer are vapor deposited.

133. The method according to one of claims 119 to 132, characterized in that the application of the base layer and of the coding layer are effected under the influence of a magnetic field.

134. The method according to one of claims 119 to 133, characterized in that a protective layer is applied to the intermediate layer, especially by vapor deposition.

135. The apparatus for carrying out the method according to one of claims 119 to 134, characterized by:

a) a supply store for a carrier foil;

b) an ion bombardment station for the ion beam application of the ion beam impingement of the coding coating;

c) a take-up store for the marking device;

136. The apparatus for carrying out the method according to claim 135, characterized by:

d) a guide device and a drive for feeding the carrier foil from the supply store through the coating station and the ion-bombardment station to the take-up store.

137. The apparatus according to claim 135 or 136, characterized in that the ion-bombardment station generates a focused ion beam and a control unit for the targeted control of the ion beam.

138. The apparatus according to one of claims 135 to 137, characterized in that an electrically-chargeable carrier foil is guided through the ion-bombardment station and is provided with a nonhomogeneous electric charge in a charging device.

139. The apparatus according to one of claims 135 or 137, characterized in that an electrically-chargeable carrier foil is guided through the ion-bombardment station and has a nonhomogeneous electric charge and that the guide device effects a joining of the carrier foil and charging foil upstream of the ion-bombardment station.

140. The apparatus according to claim 139, characterized in that a supply store for the charging foil is provided upstream of the ion-bombardment station and a take-up store is provided downstream of the ion-bombardment station and a charging device is provided for nonhomogeneously charging the charging foil between the supply store and the ion-bombardment station.

141. The apparatus according to claim 139, characterized in that the charging foil is configured as an endless foil and is guided via the guide device together with the carrier foil through the ion-bombardment stations and that the charging device is provided upstream of the ion-bombardment station in the travel direction of the carrier foil and a quenching device is provided between the ion-bombardment station and the charging device for discharging or homogenizing the electric charge.

142. The apparatus according to claim 141, characterized in that the charging foil is stretched on a support roll which is juxtaposed with the ion-bombardment station.

143. The apparatus according to one of claims 135 to 136, characterized in that the ion-bombardment station is juxtaposed with a support roll over whose roll peripherally the carrier foil is guided past the ion-bombardment stations and that the roll periphery is electrically-chargeable whereby the charging device is provided for applying a patterned electric charge which is the same as the charge of an ion beam, and a quenching device for homogenizing the electric charge or for discharging it.

144. The apparatus according to claim 143, characterized in that the quenching device and writing device are arranged after one another in the direction of rotation of the support roll in the region of the roll periphery which is free from the carrier foil.

145. The apparatus according to claim 143 or 144, characterized in that the roll periphery has a coating which is chargeable with an electric charge.

146. The apparatus according to one of claims 135 to 137, characterized in that the ion-bombardment station has a masking foil passed therethrough and the guide device effects a joining of the carrier foil and masking foil upstream of the ion-bombardment station in such manner that the ion bombardment is effected from the side of the masking foil and that the guide device separates the carrier foil and the masking foil downstream of the ion-bombardment station.

147. The apparatus according to claim 146, characterized in that between a supply store for the masking foil and the joining of the masking foil and the carrier foil a mask-forming station is arranged to produce openings in the masking foil.

148. The apparatus according to claim 147, characterized in that the mask-forming station has a laser-burning device.

149. The apparatus according to claim 148, characterized in that the mask-forming station has a control device for varying the position of the laser-burning device.

150. The apparatus according to one of the claims 135 to 149, characterized in that a further coating station is provided for applying a protective layer to the coding layer.

151. The apparatus according to one of the claims 135 to 150, characterized in that the coating stations have vapor-deposition devices.

152. The apparatus according to one of the claims 135 to 151, characterized in that the supply store is configured as a supply roll and the take-up store has a storage roll.

153. The apparatus according to one of the claims 135 to 152, characterized in that the coating stations and the ion-bombardment station have carrier rolls over whose roll peripheries the carrier foil is guided.