Magnetic ink composition, security element, and value document

Abstract

The invention relates to a magnetic ink composition comprising a first magnetic material and a second magnetic material, the first magnetic material and the second magnetic material being present in the magnetic ink composition as a mixture. The first magnetic material has a first coercivity, and the second magnetic material has a second coercivity that differs from the first coercivity. The first magnetic material and the second magnetic material are each a low-coercivity magnetic material, or the first magnetic material and the second magnetic material are each a high-coercivity magnetic material. The invention also relates to a security element (10) comprising the magnetic ink composition, and to a value document (1) comprising the security element (10).

Description

[0001] Magnetic color composition, security element and valuable document

[0002] The present invention relates to magnetic inks for valuable documents. In particular, the invention relates to a magnetic ink composition, a security element with such a magnetic ink composition, and a valuable document with the security element.

[0003] Security features, such as security strips or security threads, are often used on valuable documents like banknotes. These security features can contain magnetic or magnetizable pigment particles that give them specific magnetic properties. These specific magnetic properties can be detected in a verification process using suitable sensors to identify counterfeit security features or counterfeit valuable documents.

[0004] The magnetic material can be provided in the security element either continuously or only in certain areas, for example, in the form of a code. For example, a specific sequence of magnetic and non-magnetic areas, characteristic of the respective security document, serves as the magnetic coding of a security element. Different magnetic materials can be used for magnetic coding in the various magnetic areas, for example, with different coercive field strengths. The magnetic material can be provided with a magnetic paint composition that is applied to or integrated into the security element in certain areas. It is an object of the present invention to enable more reliable adjustment of the overall coercive field strength of a low-coercive or a high-coercive magnetic material.

[0005] This problem is solved by the subject matter of the independent claims. Further features of the invention will become apparent from the dependent claims, the following description, and the figures.

[0006] According to one aspect, a magnetic paint composition is provided. The magnetic paint composition comprises a first magnetic material and a second magnetic material, wherein the first and second magnetic materials are present in the magnetic paint composition in a mixed form. The first magnetic material has a first coercive field strength, and the second magnetic material has a second coercive field strength that differs from the first coercive field strength. The first and second magnetic materials are each either low-coercive or high-coercive. The first and second magnetic materials are, in particular, hard magnetic materials.

[0007] In other words, it is intended that either both magnetic materials in the magnetic color composition represent low-coercive magnetic materials or - alternatively - both magnetic materials in the magnetic color composition represent high-coercive magnetic materials.

[0008] With the magnetic paint composition according to the invention, it is therefore possible to combine or mix two low-coercive magnetic materials for one and the same magnetic paint composition in order to selectively adjust the overall coercivity for this magnetic paint composition. The first low-coercive magnetic material can serve as a base magnetic material, and by adding the second low-coercive magnetic material, the overall coercivity of the resulting low-coercive (total) magnetic material for the magnetic paint composition can be selectively varied, for example, increased or decreased. In this way, a predetermined specification regarding a maximum overall coercive field strength for the magnetic paint composition, and thus for a magnetic area of ​​a safety element containing the magnetic paint composition, can be more reliably maintained.In particular, the total coercive field strength of the magnetic paint composition lies between the first and second coercive field strengths.

[0009] Alternatively, with the magnetic paint composition according to the invention, it is possible to combine or mix two high-coercive magnetic materials for one and the same magnetic paint composition in order to selectively adjust the overall coercivity for this magnetic paint composition. The first high-coercive magnetic material can again serve as a base magnetic material, whereby the overall coercivity of the resulting high-coercive (total) magnetic material for the magnetic paint composition can be selectively varied, for example, increased or decreased, by adding the second high-coercive magnetic material. In this way, a predetermined specification regarding a minimum overall coercive field strength for the magnetic paint composition, and thus for a magnetic area of ​​the safety element containing the magnetic paint composition, can be more reliably maintained.Here too, the overall coercive field strength of the magnetic paint composition lies specifically between the first and second coercive field strengths. When applied to a security element, the magnetic paint composition can define a magnetic area that forms or covers a section of the security element's surface. In particular, several such magnetic areas can form a magnetic encoding of the security element. Based on this magnetic encoding, for example, the authenticity and / or type of the security element or a valuable document associated with the security element can be determined.

[0010] The magnetic coding can include the magnetic color composition or magnetic areas comprising the first magnetic material and the second magnetic material, which provide certain magnetic properties, for example a specific overall coercivity and / or a specific remanence, for the magnetic area.

[0011] The first and second magnetic materials can be incorporated into the ink or magnetic ink composition printed onto a section of the security element, thus forming the magnetic area containing the first and second magnetic materials. This creates a so-called magnetic bit, which is part of the aforementioned magnetic encoding. The magnetic ink composition can be printed onto the security element using various printing methods, including letterpress, gravure, offset, screen printing, digital printing, indirect printing, flexographic printing, thermal printing, laser printing, inkjet printing, dot matrix printing, and others.

[0012] Low-coercive magnetic materials are generally defined as hard magnetic materials with a coercive field strength significantly less than 1000 oersted (approx. 79,577.47 A / m), and usually less than 800 oersted (approx. 63,661.98 A / m). High-coercive magnetic materials, on the other hand, are generally defined as hard magnetic materials with a coercive field strength significantly greater than 1000 oersted. In one embodiment, a low-coercive magnetic material has a coercive field strength of less than 800 oersted.

[0013] A magnetic paint composition in which both the first and second magnetic materials have low coercivity can be referred to as a LoCo paint (low-coercivity paint). A magnetic paint composition in which both the first and second magnetic materials have high coercivity can be referred to as a HiCo paint (high-coercivity paint).

[0014] The magnetic color composition can therefore be selected such that both the first and second magnetic materials are low-coercive. Alternatively, the magnetic color composition can also be selected such that both the first and second magnetic materials are high-coercive.

[0015] If both magnetic materials are low-coercive, the first magnetic material can have a predetermined coercivity, for example, in the range between 500 Oe (approx. 39,788.74 A / m) and 100 Oe (approx. 7,957.75 A / m), preferably between 400 Oe (approx. 31,830.99 A / m) and 150 Oe (approx. 11,936.62 A / m), and particularly preferably between 300 Oe (approx. 23,873.24 A / m) and 200 Oe (approx. 15,915.49 A / m). The remanence of the first magnetic material can be between 80% and 20% of the saturation magnetization, preferably between 60% and 30% of the saturation magnetization. An example of a first magnetic material is BASF 345 with a coercive field strength of 270 Oe (approx. 21485.92 A / m). By adding the second magnetic material, the total coercive field strength of the first and second magnetic materials can be precisely adjusted, i.e., varied, depending on how much of the second magnetic material is mixed with the first.In other words, the coercive field strength of the LoCo paint can be precisely adjusted by mixing magnetic pigment particles with different, but closely related, coercive field strengths (in the low-coercive range). The overall resulting coercive field strength of the magnetic paint composition can be adjusted by varying the proportions of the pigment particles with differing coercive field strengths.

[0016] In one example, the first magnetic material can have a coercive field strength of 265 oersted (approx. 21,088.03 A / m) to 300 oersted (approx. 23,873.24 A / m), and the second magnetic material 240 oersted (approx. 19,098.59 A / m) to 290 oersted (approx. 23,077.47 A / m). By adding the second magnetic material to the first, the overall coercive field strength of the magnetic paint composition can be precisely adjusted. For example, BASF pigments M340 and M345 can be used for the first and second magnetic materials, respectively. The difference in the coercive field strengths of the first and second magnetic materials can be, for example, a maximum of 200 oersted, preferably a maximum of 100 oersted. This allows for particularly precise adjustment of the overall coercive field strength. In a specific example, the first magnetic material can have a coercive field strength of 260 Oersted (approx. 20690.14 A / m) and the second magnetic material a coercive field strength of 275 Oersted (approx. 21883.80 A / m).The mixing ratio of the first and second magnetic materials is chosen so that the magnetic paint composition achieves the desired overall coercive field strength. It can be determined by calculation or empirically and can take on any value, e.g., 50% to 50%, 10% to 90%, 90% to 10%, or any value in between. In the case that both magnetic materials are high-coercive, the first magnetic material can have a predetermined coercivity, for example, in the range between 5000 Oe (approx. 397,887.36 A / m) and 1000 Oe (approx. 79,577.47 A / m), preferably between 4500 Oe (approx. 358,098.62 A / m) and 1500 Oe (approx. 119,366.21 A / m), and particularly preferably between 4000 Oe (approx. 318,309.89 A / m) and 3000 Oe (approx. 238,732.41 A / m). By adding the second magnetic material, the total coercive field strength of the first and second magnetic materials can be precisely adjusted, i.e., varied, depending on the amount of the second magnetic material added to the first.In other words, the coercive field strength of the HiCo paint can be precisely adjusted by mixing pigment particles with different coercive field strengths (in the high-coercive range). The overall resulting coercive field strength of the magnetic paint composition can be adjusted by varying the proportions of the pigment particles with their respective coercive field strengths.

[0017] This targeted adjustment of the overall coercive field strength of the magnetic paint composition, both for combinations of two low-coercive magnetic materials and for combinations of two high-coercive magnetic materials, is particularly advantageous because it is not always possible to predict the final coercive field strength of a magnetic paint during its production. Adding another magnetic material with a known coercive field strength allows for subsequent adjustment of the resulting overall coercive field strength of the magnetic paint. This is because, during the manufacturing process of a paint with low-coercive magnetic material, it may be possible to...It can occur that the coercive field strength of the magnetic paint exceeds or falls below a specific specification range defined for the low-coercive magnetic range. This can be avoided by the magnetic paint composition according to the invention, which comprises two low-coercive magnetic materials with closely spaced coercive field strengths. The same applies analogously to a manufacturing process of a paint with high-coercive magnetic material, where it may occur that the coercive field strength of the magnetic paint exceeds or falls below a specific specification range defined for the high-coercive magnetic range. This can be avoided by the magnetic paint composition according to the invention, which comprises two high-coercive magnetic materials with closely spaced coercive field strengths.

[0018] In one example, the magnetic paint composition can include a third magnetic material with a third coercivity, where the third magnetic material is also a low-coercivity material. The third coercivity may differ from the first and second coercivity of the first and second magnetic materials, respectively, but all three coercivity values ​​are close to each other, as they all lie within the range of low coercivity, for example, in coercivity ranges such as those previously described for low-coercivity magnetic materials.

[0019] The terms “coercivity” and “coercive field strength”, which can be used synonymously here, can define the magnetic field strength that is necessary to completely demagnetize a magnetic material previously charged to saturation flux density, so that the resulting total flux or local flux density is zero.

[0020] The term "remanence" can be understood as a magnetization that a magnetic material, which was previously saturated (i.e., maximally magnetized) by an external magnetic field, retains after the magnetic field is removed. As already indicated above, the magnetic ink composition according to the invention can be used to verify the authenticity and / or the type of a security element or an associated security document. In a corresponding verification method, for example, a magnetic field or successively several different magnetic fields can be applied to the aforementioned magnetic area of ​​the security element, which contains the magnetic ink composition, thereby magnetizing the magnetic material of the magnetic area, i.e., the first magnetic material and the second magnetic material. Subsequently, the remanence of the magnetic area or the magnetization can be determined using suitable sensors. The determined remanence orThe magnetization of the magnetic area can then be used, possibly together with remanence values ​​or magnetization values ​​of other magnetic areas, to test the safety element.

[0021] The magnetic area can be arranged in series with several other magnetic areas along a coding direction on a security element, such that a specific magnetic coding is provided by the series of magnetic areas. This magnetic coding can be used to test the security element using the verification procedure described above, thus determining its authenticity and / or type.

[0022] According to one embodiment, the first coercive field strength and the second coercive field strength can each be at least 100 oersted, in particular in a range between 100 and 500 oersted, preferably in a range between 150 and 400 oersted, more preferably in a range between 200 and 300 oersted, wherein a total coercive field strength of the first magnetic material and the second magnetic material is in particular at most 500 oersted.

[0023] In this case, both the first and second magnetic materials are low-coercive magnetic materials, with the coercive field strengths of both magnetic materials differing but being close to each other, i.e., within the specified ranges.

[0024] In one example, the total coercive field strength of the first magnetic material and the second magnetic material is at most 300 Oersted.

[0025] In this way, a [product / service] can be used for specific purposes.

[0026] The magnetic paint composition must adhere to the specified parameters. For example, if the coercive field strength of the first magnetic material is below 300 oersted before the paint manufacturing process, but is increased to above 300 oersted through certain manufacturing steps, then the second magnetic material can be used to reduce the total coercive field strength of the first and second magnetic materials, thus keeping the total coercive field strength below 300 oersted.

[0027] According to one embodiment, the first magnetic material and the second magnetic material are each a low-coercive magnetic material and the difference in the coercive field strengths of the first and second magnetic materials is at most 200 Oersted (approx. 15915.49 A / m), preferably at most 100 Oersted (approx. 7957.75 A / m).

[0028] In other words, the coercive field strengths of the two magnetic materials are close to each other. According to one embodiment, the first coercive field strength and the second coercive field strength can each be at least 1000 oersted, in particular in a range between 1000 and 5000 oersted, preferably in a range between 1500 and 4500 oersted, and more preferably in a range between 3000 and 4000 oersted, wherein the total coercive field strength of the first magnetic material and the second magnetic material is in particular at least 1000 oersted.

[0029] In this case, both the first and second magnetic materials are high-coercive magnetic materials, with the coercive field strengths of both magnetic materials differing but being close to each other, i.e., within the specified ranges.

[0030] In one example, the total coercive field strength of the first magnetic material and the second magnetic material is at least 1000 Oersted.

[0031] In this way, a [product / service] can be used for specific purposes.

[0032] The magnetic paint composition must adhere to the specified specifications. For example, if the coercive field strength of the first magnetic material is above 1000 oersted before the paint manufacturing process, but is reduced to below 1000 oersted through certain manufacturing steps, then the second magnetic material can be used to increase the total coercive field strength from the first and second magnetic materials, thus maintaining the total coercive field strength above 1000 oersted.

[0033] According to one embodiment, the first magnetic material and the second magnetic material are contained in a carrier medium in which the first magnetic material and the second magnetic material are each distributed in the form of a plurality of magnetic pigment particles.

[0034] The carrier material can be a binder in which the magnetic pigment particles are finely distributed or dispersed. The first, second, and / or, if applicable, third magnetic material of the magnetic ink composition can contain magnetically alignable pigment particles. These magnetically alignable pigment particles can have an elongated or platelet shape, so that changing their orientation can also create a color effect to produce angle-dependent changes in hue or gloss. Once applied to and aligned with the security feature, the magnetically alignable pigment particles can cause changes in hue or gloss when the security feature is viewed from different angles. Such color effects can further enhance counterfeit protection and can also be used to improve aesthetics.

[0035] According to one aspect, a safety element is provided which has at least one magnetic area with the magnetic color composition described herein according to the invention.

[0036] The at least one magnetic area can form or cover a surface section of the security element. In particular, several of the magnetic areas according to the invention can form a magnetic encoding of the security element. The magnetic encoding can be used, for example, to determine the authenticity and / or type of the security element or of a valuable document associated with the security element. The magnetic encoding can include the magnetic color composition comprising the first magnetic material and the second magnetic material, which provides specific magnetic properties, for example, a specific overall coercivity and / or a specific remanence, for the at least one magnetic area.

[0037] The magnetic ink composition can be printed onto a section of the security element to form at least one magnetic area containing the first and second magnetic materials. This creates a so-called magnetic bit, which is part of the aforementioned magnetic encoding. The magnetic ink composition can be printed onto the security element using various printing methods, including letterpress, gravure, offset, screen printing, digital printing, indirect printing, flexographic printing, thermal printing, laser printing, inkjet printing, dot matrix printing, and more.

[0038] According to one embodiment, the safety element is a safety thread which includes the at least one magnetic area, or a foil element which includes the at least one magnetic area.

[0039] The at least one magnetic area can be arranged on or within the safety thread or foil element. Several of the at least one magnetic area and / or additional magnetic areas with different magnetic properties, in particular with different total coercive field strengths, can be arranged on or within the safety thread or foil element. The magnetic coding then results from the combination of the at least one magnetic area with the additional magnetic areas. For example, a plurality of magnetic areas can be provided on or within the safety element, each exhibiting the properties of the at least one magnetic area described herein.

[0040] According to one embodiment, the at least one magnetic area has a length along a coding direction of at least 1 mm and at most 6 mm, preferably a length along a coding direction of at least 2 mm and at most 6 mm.

[0041] The coding direction can define a direction along which several magnetic areas are arranged one after the other. For example, the coding direction extends along a longitudinal dimension of the security thread.

[0042] In one example, the at least one magnetic area has a width perpendicular to the coding direction of at least 1 mm and at most 6 mm, preferably a width perpendicular to the coding direction of at least 2 mm and at most 6 mm.

[0043] As mentioned previously, the safety element can be a safety thread. The maximum width of 6 mm of the at least one magnetic area can correspond to the width of the safety thread. Several of the at least one magnetic area can be arranged one behind the other along the length of the safety thread. Alternatively, several of the at least one magnetic area can be arranged side by side on the safety thread, i.e., transversely to the length of the safety thread or along the thread width. According to one embodiment, the safety element has a magnetic coding which, preferably along a coding direction, includes at least one or more of the magnetic areas, preferably one or more of the magnetic areas and further magnetic areas.

[0044] According to one embodiment, the safety element has a further magnetic area with a further magnetic material, wherein the further magnetic area is spatially separated from or (immediately) adjacent to the at least one magnetic area. The further magnetic material can be a soft magnetic material or it can be a hard magnetic material with a further coercive field strength that differs from the first coercive field strength and / or from the second coercive field strength, wherein the first magnetic material and the second magnetic material of the at least one magnetic area are high-coercive magnetic materials and the further magnetic material is low-coercive magnetic material, or wherein the first magnetic material and the second magnetic material of the at least one magnetic area are low-coercive magnetic materials and the further magnetic material is high-coercive or a soft magnetic material.

[0045] Preferably, the first and second magnetic materials are each low-coercive, and the further magnetic material is a high-coercive or soft magnetic material, or the first and second magnetic materials are each high-coercive, and the further magnetic material is a low-coercive. This allows for the creation of a magnetic encoding with differently coercive magnetic materials, where the coercive field strength of at least one of the magnetic materials can be precisely adjusted. In this way, different magnetic regions with different overall coercive field strengths can be provided, wherein the overall coercive field strength of the at least one magnetic region is defined by the mixture of the first and second magnetic materials within that region, and the overall coercive field strength of the further magnetic region is defined by the additional coercive field strength of the further magnetic material.These different magnetic areas can be spaced apart from each other, thus forming different magnetic bits or surface areas of the security element. The different magnetic areas can be arranged in any configuration relative to each other.

[0046] According to one embodiment, the additional coercive field strength is at least 100 oersted, and is particularly in a range between 100 and 500 oersted, preferably in a range between 150 and 400 oersted, and more preferably in a range between 200 and 300 oersted. Alternatively, the additional coercive field strength is at least 1000 oersted, and is particularly in a range between 1000 and 5000 oersted, preferably in a range between 1500 and 4500 oersted, and more preferably in a range between 3000 and 4000 oersted.

[0047] In the first alternative, the additional magnetic material is a low-coercive magnetic material. In the second alternative, the additional magnetic material is a high-coercive magnetic material.

[0048] In one example, the distance between the at least one magnetic area and the other magnetic area along a coding direction is at least 2 mm. If the security element is a security thread, the at least one magnetic area and the other magnetic area can be spaced apart from each other. A non-magnetic area, such as a non-magnetic material of the security element, can be located between the two magnetic areas.

[0049] According to one aspect, a security document is provided with the security element according to the invention.

[0050] The valuable document could be, for example, a banknote, a share, a bond, a certificate, a voucher, a check, a lottery ticket, an admission ticket, a passport, an identity card, etc.

[0051] The security element can be applied to the security document or embedded or integrated into the security document.

[0052] According to one embodiment, the security element is a foil strip or foil patch applied to the security document, or a security thread applied to the security document or fully or partially embedded in the security document.

[0053] According to one embodiment, the security document comprises a base substrate, wherein the at least one magnetic area is applied to or embedded in the base substrate.

[0054] The at least one magnetic area can, for example, be applied directly to the base substrate of the security document. The base substrate can be a paper substrate, a plastic substrate such as a polymer substrate, or a hybrid substrate, that is, a combination of paper and plastic substrates.

[0055] According to one embodiment, the security document comprises a pressure-acceptance layer, wherein the pressure-acceptance layer at least partially covers the at least one magnetic area.

[0056] The pressure-receiving layer can be a cover layer positioned over the at least one magnetic area to partially or completely cover it. Particularly in polymer substrates, the at least one magnetic area—that is, the magnetic encoding provided by the at least one magnetic area—can be positioned beneath the pressure-receiving layer, making the at least one magnetic area of ​​the security element invisible to the naked eye. The pressure-receiving layer protects the at least one magnetic area from wear or abrasion during document circulation. It also prevents any potentially disruptive optical effect of the at least one magnetic area.

[0057] The magnetic ink composition according to the invention can be a printing ink that can be applied to a security element, such as the security element described above, or to a valuable document by means of various printing processes.

[0058] In particular, the magnetic ink composition can be applied directly to the security document or embedded within it.

[0059] The security document can comprise a paper substrate, a plastic substrate such as a polymer substrate, or a hybrid substrate, that is, a combination of paper and plastic substrates. A corresponding magnetic encoding, provided by the magnetic ink composition, can be printed directly onto the security document substrate as an alternative to an embedded or applied security element, such as a security thread, a foil strip, or a foil patch, particularly onto polymer substrates or so-called hybrid substrates.

[0060] Due to the larger surface area of ​​the document substrate compared to a security thread or security foil, the encoding possibilities are increased many times over. The different magnetic areas can be printed onto the document substrate in any desired arrangement.

[0061] Particularly in the case of polymer substrates, the magnetic coding provided by the magnetic ink composition can preferably be positioned under one or more printing layers, so that the magnetic ink composition introduced into the security document is neither visually disturbing, nor detectable, nor worn down or lost through abrasion in the circulation of the security document.

[0062] In hybrid substrates consisting of a combination of paper and foil, e.g., a sequence of foil / paper / foil or paper / foil / paper or paper / foil, the magnetic encoding provided by the magnetic ink composition may preferably be located inside the composite, for example, between individual layers within the security document.

[0063] The magnetic paint composition may contain one or more of the following

[0064] The components include: magnetic pigments in the form of the first and second magnetic materials, binder as a carrier material for the magnetic pigments, chalk, anti-discarding paste, mineral oil, polyethylene wax and drying agent.

[0065] Exemplary embodiments of the invention are explained in more detail below with reference to schematic drawings.

[0066] Fig. 1 shows a security document with a security element which has three magnetic areas with identical total coercive field strengths.

[0067] Fig. 2 shows a security document with a security element which has two magnetic areas with identical total coercive field strengths and another magnetic area with a further coercive field strength.

[0068] Fig. 3 shows a security document with a security element which has three magnetic areas, each with different total coercive field strengths.

[0069] Fig. 4 shows a cross-sectional view of the security document from Fig. 1.

[0070] Fig. 5 shows a cross-sectional view of another example of a

[0071] Valuable document.

[0072] In the figures, identical or functionally equivalent elements are given the same reference symbols.

[0073] Fig. 1 shows a security document 1 with a security element 10, which has three

[0074] Magnetic areas 12 with identical or nearly identical

[0075] The total coercive field strengths are present. Each of the three magnetic regions 12 comprises a first magnetic material and a second magnetic material, wherein the first and second magnetic materials exist in a mixed form within the respective magnetic region 12. The first magnetic material has a first coercive field strength, and the second magnetic material has a second coercive field strength that differs from the first coercive field strength. Both the first and second magnetic materials are low-coercive magnetic materials. Alternatively, both the first and second magnetic materials are high-coercive magnetic materials.

[0076] For the first alternative (both magnetic materials are low-coercive), this means that the first coercive field strength and the second coercive field strength lie in a range between 100 and 500 oersted, preferably in a range between 150 and 400 oersted, and more preferably in a range between 200 and 300 oersted. The total coercive field strength resulting from the mixture of both magnetic materials may not exceed a value of 300 oersted.

[0077] For the second alternative (both magnetic materials are high-coercive), this can mean that the first coercive field strength and the second coercive field strength lie in a range between 1000 and 5000 oersted, preferably in a range between 1500 and 4500 oersted, and more preferably in a range between 3000 and 4000 oersted. The total coercive field strength resulting from the mixture of both magnetic materials may not fall below a value of 1000 oersted.

[0078] The security element 10 can have a security thread 20 on which the three magnetic areas 12 are applied. The three magnetic areas 12 are arranged, in particular, spaced apart from each other or spatially separated from each other on the security thread 20. The magnetic areas 12 can extend over the entire width of the security thread 20 (as shown in the figures) or only over a portion of the width of the security thread 20, the width being defined by a direction perpendicular to a coding direction of the magnetic areas 12. The magnetic areas 12 can also have different widths, lengths, or shapes. The security thread 20 is attached to a document substrate 22 of the document 1. In the example shown in Fig. 1, it extends over the entire width of the document 1.

[0079] The three magnetic areas 12 can have a magnetic color composition. In particular, the magnetic color composition may have been applied to the security document 1 or to the security element 10 during a manufacturing process, for example by printing, in order to form the three magnetic areas 12.

[0080] Fig. 2 shows a security document 1 with a security element 10, which has two magnetic areas 12 with identical total coercive field strengths and a further magnetic area 14 with a different coercive field strength. The different coercive field strengths of the individual areas are indicated by differently oriented hatching. The two magnetic areas 12 shown in Fig. 2 are, in particular, magnetic areas 12 as described with reference to Fig. 1. In this regard, reference is made to the explanations relating to Fig. 1.

[0081] Furthermore, the safety element 10 now includes the additional magnetic area 14, which, for example, contains a single magnetic material with a specific coercive field strength. This magnetic material can be a low-coercive or a high-coercive magnetic material. However, it is also possible that the additional magnetic area 14 contains two or more magnetic materials, which are either all low-coercive or all high-coercive magnetic materials, or a mixture of low-coercive and high-coercive magnetic materials.

[0082] Fig. 3 shows a security document 1 with a security element 10, which has three magnetic areas 12, 14, 16, each with different total coercive field strengths. The different coercive field strengths of the individual areas are indicated by differently oriented hatching. The magnetic area 12 shown in Fig. 3 is, in particular, a magnetic area 12 as described with reference to Fig. 1. In this regard, reference is made to the explanations relating to Fig. 1.

[0083] In addition, the safety element 10 now includes the two further magnetic areas 14 and 16, which, for example, have magnetic materials with different coercive field strengths.

[0084] The magnetic material of the further (second) magnetic region 14 can be a low-coercive or a high-coercive magnetic material. However, it is possible that the further (second) magnetic region 14 has two or more magnetic materials, which are either all low-coercive or all high-coercive magnetic materials, or a mixture of low-coercive and high-coercive magnetic materials.

[0085] The magnetic material of the further (third) magnetic region 16 can be a low-coercive or a high-coercive magnetic material. However, it is possible that the further (third) magnetic region 16 contains two or more magnetic materials, which are either all low-coercive or all high-coercive magnetic materials, or a mixture of low-coercive and high-coercive magnetic materials.

[0086] The magnetic areas 12, 14, and 16 of Figures 1 to 3 can each form magnetic codes, also known as bits. Each magnetic area 12, 14, and 16 can form a contiguous area with a free outline. In the examples shown, all magnetic areas 12, 14, and 16 are rectangular, with the opposite longer sides of the rectangles bounded by the thread edges of the safety thread 20.

[0087] Preferably, the different magnetic areas 12, 14 and 16 have a distance from each other of preferably 2 mm or more. This facilitates detection during the verification of the security document 1.

[0088] Other exemplary shapes for magnetic areas 12, 14, and 16 are squares, circles, or triangles. However, magnetic areas 12, 14, and 16 can also be applied to the security document 1 or the security element 10, or the security thread, in the form of information such as text and / or symbols.

[0089] The magnetic areas 12, 14, and 16 can preferably be arranged one behind the other in the longitudinal direction of the security thread 20, but other arrangements are also possible, for example, side by side in the direction of the thread width of the security thread 20, i.e., transversely to the longitudinal direction of the thread. The magnetic areas 12, 14, and 16 preferably have clear outlines (edges), as this leads to a concentration of the emerging magnetic field lines, which can generally be detected more easily by the sensors. Fig. 4 shows a cross-sectional view of the security document from Fig. 1. This figure shows an example of how the security element 10 or the magnetic color composition according to the invention can be embedded in the security document 1.In particular, the security element 10 or the magnetic ink composition can be applied to a surface of a security document substrate 22 of the security document 1, wherein a further layer 23 covers the applied security element 10 or the applied magnetic ink composition.

[0090] In one example, the magnetic ink composition can be applied or printed directly onto the document substrate 22 as an alternative to the security element 10 to be inserted or applied. The magnetic ink composition can be located beneath the additional layer 23, which is, for example, a print-accepting layer 23, so that the magnetic ink composition is concealed and also protected from mechanical influences during document circulation. The print-accepting layer 23 can, for example, be a layer of the document 1 to be printed on.

[0091] Fig. 5 shows a cross-sectional view of another example of a security document 1 with the security element 10 according to the invention or with the color composition according to the invention. The security document 1 is a composite of several layers 24, 25, and 26, wherein the security element 10 according to the invention is arranged between two layers 25 and 26 of the composite. Alternatively, the color composition according to the invention can be arranged directly between the two layers 25 and 26 of the composite. The security document 1 shown in Fig. 5 can be a so-called hybrid substrate, which can consist of a combination of paper and (plastic) film, e.g., a sequence of film / paper / film or paper / film / paper.

Claims

Patent claims 1. Magnetic paint composition comprising: a first magnetic material and a second magnetic material, wherein the first magnetic material and the second magnetic material are present in the magnetic paint composition in mixed form, wherein the first magnetic material has a first coercive field strength and the second magnetic material has a second coercive field strength which differs from the first coercive field strength, wherein the first magnetic material and the second magnetic material are each a low-coercive magnetic material or the first magnetic material and the second magnetic material are each a high-coercive magnetic material.

2. Magnetic color composition according to claim 1, wherein the first coercive field strength and the second coercive field strength each amount to at least 100 oersted, in particular in a range between 100 and 500 oersted, preferably in a range between 150 and 400 oersted, more preferably in a range between 200 and 300 oersted; and wherein a total coercive field strength of the first magnetic material and the second magnetic material is in particular at most 500 oersted.

3. Magnetic color composition according to one of the preceding claims, wherein the first magnetic material and the second magnetic material are each a low-coercivity magnetic material and the difference of The coercive field strengths of the first and second magnetic materials are at most 200 Oersted, preferably at most 100 Oersted.

4. Magnetic color composition according to claim 1, wherein the first coercive field strength and the second The coercive field strength of each material is at least 1000 oersted, in particular in a range between 1000 and 5000 oersted, preferably in a range between 1500 and 4500 oersted, and more preferably in a range between 3000 and 4000 oersted; and wherein the total coercive field strength of the first magnetic material and the second magnetic material is in particular at least 1000 oersted.

5. Magnetic color composition according to one of the preceding claims, wherein the first magnetic material and the second magnetic material are contained in a carrier medium in which the first magnetic material and the second magnetic material are each distributed in the form of a plurality of magnetic pigment particles.

6. Security element (10) for a valuable document (1), comprising: at least one magnetic area (12) with a magnetic color composition according to one of the preceding claims.

7. Safety element (10) according to claim 6, wherein the safety element (10) is a safety thread (20) comprising the at least one magnetic area (12); or wherein the safety element (10) is a foil element (20) comprising the at least one magnetic area (12).

8. Safety element according to one of claims 6 to 7, wherein the safety element (10) has a magnetic coding which, preferably along a coding direction, has one or more of the magnetic areas (12), preferably one or more of the magnetic areas (12) and further magnetic areas (14, 16).

9. Security element (10) according to one of claims 6 to 8, wherein the at least one magnetic area (12) has a length along a coding direction of at least 1 mm and at most 6 mm, preferably a length along a coding direction of at least 2 mm and at most 6 mm.

10. Safety element (10) according to one of claims 6 to 9, comprising: a further magnetic area (14) with a further magnetic material, wherein the further magnetic area (14) is spatially separated from or adjacent to the at least one magnetic area (12), wherein the further magnetic material has a further coercive field strength which differs from the first coercive field strength and / or from the second coercive field strength, wherein the first magnetic material and the second magnetic material of the at least one magnetic area are a high-coercive magnetic material and the further magnetic material is a low-coercive magnetic material, or wherein the first magnetic material and the second magnetic material of the at least one magnetic area are a low-coercive magnetic material and the further magnetic material is a high-coercive or a soft magnetic magnetic material.

11. Safety element (10) according to claim 10, wherein the further coercive field strength is at least 100 Oersted, in particular in a range between 100 and 500 Oersted, preferably in a range between 150 and 400 Oersted, more preferably in a range between 200 and 300 Oersted; or wherein the further coercive field strength is at least 1000 Oersted, in particular in a range between 1000 and 5000 Oersted, more preferably in a range between 1500 and 4500 Oersted, more preferably in a range between 3000 and 4000 Oersted.

12. Security document (1) with a security element (10) according to one of claims 6 to 11.

13. Security document (1) according to claim 12, wherein the security element (10) is a foil strip applied to the security document (1) or a foil patch applied to the security document (1) or a security thread (20) applied to the security document (1) or fully or partially embedded in the security document (1).

14. Security document (1) according to claim 12, comprising: a base substrate (22), wherein the at least one magnetic area (12) is applied to the base substrate (22) or is embedded in the base substrate (22).

15. Security document (1) according to one of claims 12 to 14, comprising: a pressure acceptance layer (23), wherein the pressure acceptance layer (23) covers at least part of the at least one magnetic area (12).

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