Method for producing an optical effect layer containing magnetic or magnetisable pigment particles and exhibiting one or more indicia - Patents.com

Abstract

The present invention relates to the field of protection of security documents, such as for example banknotes and identity documents against counterfeiting and illegal copying. In particular, the present invention provides a method for producing an optical effect layer (OEL) exhibiting one or more indicia (x30) on a substrate (x20), comprising the steps of exposing a coating layer (x10) comprising non-spherical magnetic or magnetizable pigment particles to a magnetic field of a magnetic field generating device in order to orient at least a portion of the non-spherical magnetic or magnetizable pigment particles, applying a top coating composition on the coating layer (x10) in the form of one or more indicia (x30), and at least partially curing the coating layer (x10) and the one or more indicia (x30) in a curing device (x50).

Description

Detailed Description of the Invention

[0001] [Field of the Invention]

[0001] The present invention relates to the field of methods for producing optical effect layers (OELs) containing magnetically oriented non-spherical magnetic or magnetizable pigment particles. In particular, the present invention provides a method for magnetically orienting non-spherical magnetic or magnetizable pigment particles in a coating layer to produce an OEL, as well as the use of said OELs for decorative purposes as well as as an anti-counterfeiting measure for security documents or articles.

[0002] [Background of the invention]

[0002] It is known in the art to use inks, compositions, coatings or layers comprising oriented magnetic or magnetisable pigment particles, in particular also optically variable magnetic or magnetisable pigment particles, for the production of security elements, for example in the field of security documents. Coatings or layers comprising oriented magnetic or magnetisable pigment particles are disclosed, for example, in U.S. Pat. Nos. 2,570,856; 3,676,273; 3,791,864; 5,630,877 and 5,364,689. Coatings or layers comprising oriented magnetic colour-shifting pigment particles, which provide particularly attractive optical effects and serve to protect security documents, are disclosed in WO 2002 / 090002 and WO 2005 / 002866.

[0003]

[0003] For example, security features for security documents can generally be classified into "covert" security features on the one hand, and "overt" security features on the other hand. The protection offered by covert security features relies on the principle that such features are difficult to detect, typically requiring specialized equipment and knowledge for detection, whereas "overt" security features rely on the concept of being easily detectable by unaided human senses, e.g. such features may be visible and / or detectable by touch, whilst remaining difficult to produce and / or replicate. However, the effectiveness of overt security features depends crucially on their easy recognition as security features.

[0004]

[0004] Magnetic or magnetizable pigment particles in printing inks or coatings allow for the creation of magnetically inductive images, designs and / or patterns by the application of a correspondingly configured magnetic field, causing local orientation of the magnetic or magnetizable pigment particles in the unsolidified (i.e. wet) coating, followed by solidification of the coating. The result is a fixed, stable magnetically inductive image, design or pattern. Materials and techniques for the orientation of magnetic or magnetisable pigment particles in coating compositions are disclosed, for example, in U.S. Pat. No. 2,418,479; U.S. Pat. No. 2,570,856; U.S. Pat. No. 3,791,864, DE 2006848, U.S. Pat. No. 3,676,273, U.S. Pat. No. 5,364,689, U.S. Pat. No. 6,103,361, EP 0406667; U.S. Pat. Appl. Pub. No. 2002 / 0160194; U.S. Pat. Appl. Pub. No. 2004 / 0009309; EP 0710508; WO 2002 / 09002; WO 2003 / 000801; WO 2005 / 002866; WO 2006 / 061301. Such a method makes it possible to create magnetic induction patterns that are highly resistant to counterfeiting. The security element in question can only be created by having access to both magnetic or magnetisable pigment particles or corresponding pigment inks and the specific technology used to print said inks and to orient said pigments in the printed inks.

[0005]

[0005] In order to protect security documents or articles containing magnetically inductive images from the premature detrimental effects of soil and / or moisture over time and use, it is customary to apply a protective varnish, which is applied as a continuous layer over an already prepared, dried / cured magnetically inductive image.

[0006]

[0006] WO 2011 / 012520 discloses a transfer foil comprising a coating layer having the form of a design, said design comprising oriented optically variable magnetic pigments representing an image, indicia or pattern. The transfer foil may further comprise a top-coating layer, said top-coating layer being applied prior to the application of the layer comprising the optically variable magnetic pigment. The process of making said transfer foil comprises the steps of a) applying a top-coating layer and hardening / curing said top-coating layer, and b) applying a layer comprising the optically variable magnetic pigment, magnetically orienting the particles and hardening / curing said layer. The disclosed method is not suitable for making magnetically inductive images required to show personalized variable indicia.

[0007]

[0007] EP 1641624, EP 1937415, and EP 2155498 disclose an apparatus and method for magnetically transferring indicia to an unsolidified (i.e. wet) coating composition containing magnetic or magnetizable pigment particles to form an optical effect layer (OEL). The disclosed method allows the creation of security documents and articles with customer-specific magnetic designs. However, the disclosed magnetic devices are prepared to meet customer-specific magnetic designs and cannot be altered if the design is required to change from one article to another, and therefore the method is not suitable for creating OELs required to show personalized variable indicia.

[0008]

[0008] EP 3170566, EP 3459758, EP 2542421 and WO 2020 / 148076 disclose different methods for the creation of variable indicia in optically variable magnetic inks. However, said methods require the use of special equipment such as photomasks, lasers or addressable LEDs.

[0009]

[0009] In order to provide variable information with magnetic properties on security documents or articles, inkjet inks containing magnetic particles have been developed to enable magnetic ink character recognition (MICR). However, said inkjet inks face various problems, especially related to the shelf-life stability of the ink, ink printability, non-uniform magnetic ink deposits, and clogging of the print head. EP 2223976 discloses a method for the preparation of documents containing MICR features, comprising the steps of applying by inkjet onto a substrate a pattern of a curable ink containing a gelling agent, cooling the ink to a temperature below the gelling temperature of the ink, applying a magnetic material to the ink, and finally curing the ink. Alternatively, toners containing magnetic particles have also been developed, as disclosed, for example, in US Pat. Nos. 10,503,091 and 10,359,730. However, specific dedicated equipment is required to print those toners.

[0010]

[0010] Therefore, there is a need for a method for universally producing customized optical effect layers OELs exhibiting one or more indicia on an industrial scale, said optical effect layers exhibiting noticeable effects. Furthermore, said method should be reliable, simple to implement, and capable of operating at high production speeds.

[0011] [Summary of the Invention]

[0011] The present invention therefore aims to overcome the deficiencies of the prior art by providing a method for producing an optical effect layer (OEL), said OEL comprising a motif consisting of at least two areas of a single applied and cured layer containing non-spherical magnetic or magnetisable pigment particles and exhibiting one or more indicia (x30) on a substrate (x20), The method is: and

[0012] In one preferred embodiment, step b) of applying the top-coating composition is carried out by a non-contact fluid micro-dispensing technique, preferably an ink-jet printing process.

[0013]

[0013] Also described herein are optical effect layers (OELs) and security documents produced by the methods described herein, as well as decorative elements and decorative objects comprising one or more optical OELs described herein.

[0014]

[0014] Also described is a method for producing a security document, or a decorative element or body, the method comprising: a) providing a security document, or a decorative element or body, and b) providing an optical effect layer (OEL), such as those described herein, and in particular those obtained by the methods described herein, which is included by the security document or the decorative element or body.

[0015]

[0015] The method described herein advantageously allows the creation of an optical effect layer (OEL) consisting of a single layer and comprising two or more areas of a radiation curable coating composition comprising non-spherical magnetic or magnetizable pigment particles, said two or more areas comprising non-spherical magnetic or magnetizable pigment particles oriented according to different orientation patterns at high resolution, said method not requiring the use of a photomask or a curing unit equipped with a laser or an addressable LED curing unit.

[0016]

[0016] The method advantageously described herein uses two compositions, which are applied to each other in a wet-on-wet state. In particular, the method according to the invention allows the production of optical effect layers (OELs) universally exhibiting one or more indicia and can be easily carried out on an industrial scale at high production rates. The two compositions used in the method described herein comprise, as a first composition, a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles, which is applied onto a substrate (x20), and, as a second composition, a top-coating composition, which is applied at least partially onto the radical radiation curable coating composition comprising pigment particles, when said radical radiation curable coating composition is still in a wet unpolymerized state, and which partially overlaps said composition (i.e. overlaps in at least one area) and is applied in the form of one or more indicia.

[0017]

[0017] The present invention provides a reliable and easy to implement method of producing a highly visible optical effect layer (OEL) exhibiting one or more indicia as described herein. The disclosed method advantageously allows the production of security documents and articles with customer-specific magnetic designs that also exhibit one or more indicia in an easy to implement and highly reliable manner with generic online changes, without requiring customization of magnet assemblies used to orient non-spherical magnetic or magnetizable pigment particles for each variable or individualized indicia and for each and every customer-specific optical effect layer (OEL), and without requiring the use of solidification units with photomasks or addressable LED curing units. [Brief description of the drawings]

[0018] [Figure 1]FIG. 1 illustrates diagrammatically a method for producing an optical effect layer (OEL) on a substrate (120) according to the invention, said method comprising step b) at least partially applying a top-coating composition onto a coating layer (110) comprising non-spherical magnetic or magnetisable pigment particles, said top-coating composition being applied in the form of one or more indicia (130); following step b), applying the one or more indicia (130) and one or more areas of the coating layer (110) beneath the one or more indicia (130) to a LE D step c) of at least partially curing in a curing unit (150); following step c), step d) of exposing the coating layer (110) to a magnetic field of a magnetic field generating device (B1) in order to orient at least a portion of the non-spherical magnetic or magnetisable pigment particles in the as yet uncured areas of the coating layer (110); and partially simultaneously with or following step d), step e) of at least partially curing the coating layer (110) in a curing unit (160) radiating at least between 250 nm and 320 nm. [Diagram 2] FIG. 2 illustrates diagrammatically non-spherical, specifically platelet-shaped, pigment particles. [Figure 3A] 3A-C show photographs of OELs prepared by methods according to the invention (E1-E39) and comparative methods (C1-C6). [Figure 3B] 3A-C show photographs of OELs prepared by methods according to the invention (E1-E39) and comparative methods (C1-C6). [Figure 3C] 3A-C show photographs of OELs prepared by methods according to the invention (E1-E39) and comparative methods (C1-C6).

[0019] [Detailed Description] definition The following definitions are discussed in the detailed description and are used to interpret the meaning of terms recited in the claims.

[0020]

[0019] As used herein, the term "at least one" is meant to define one or more than one, for example, 1, 2, or 3.

[0021]

[0020] The terms "about" and "substantially" used in this specification mean that the amount or value in question is a specified specific value or some other value in its vicinity. In general, the terms "about" and "substantially" indicating a value are intended to indicate a range within ±5% of the value. As an example, the expression "about 100" indicates a range of 100 ±5, i.e., a range of 95 to 105. In general, when the terms "about" and "substantially" are used, it can be expected that similar results or effects of the present invention can be obtained within a range of ±5% of the indicated value.

[0022]

[0021] The term "substantially parallel" refers to a deviation of 10° or less from a parallel alignment, and the term "substantially perpendicular" refers to a deviation of 10° or less from a perpendicular alignment.

[0023]

[0022] As used herein, the term "and / or" means that all or only one of the elements of the group may be present. For example, "A and / or B" is intended to mean "A only, or B only, or both A and B." In the case of "A only," the term also encompasses the possibility that B is not present, i.e., "A only and no B."

[0024]

[0023] The term "comprises" as used herein is meant to be non-exclusive and non-limiting. Thus, for example, a coating composition comprising compound A may comprise other compounds in addition to A. However, the term "comprises" also encompasses the more restrictive meanings of "consisting essentially of" and "consisting of" as specific embodiments thereof, so that, for example, "a fountain solution comprising A, B and optionally C" may also consist (substantially) of A and B, or may consist (substantially) of A, B and C.

[0025]

[0024] As used herein, the term "optical effect layer" (OEL) refers to a coating layer comprising oriented magnetic or magnetizable pigment particles, which are oriented by a magnetic field and which are fixed / frozen in their orientation and position (i.e., after curing) to form a magnetically induced image.

[0026]

[0025] The term "coating composition" refers to any composition capable of forming an optical effect layer (OEL) on a solid substrate, preferably, but not limited to, applied by a printing method. The coating composition comprises the non-spherical magnetic or magnetizable pigment particles described herein, and a binder as described herein. The term "top coating composition" refers to a composition that does not comprise the non-spherical magnetic or magnetizable pigment particles described herein.

[0027]

[0026] As used herein, the term "wet" refers to an uncured coating layer, e.g., a coating layer in which non-spherical magnetic or magnetizable pigment particles are still able to change their position and orientation under the influence of external forces acting on them.

[0028]

[0027] The term "(meth)acrylate" in the context of the present invention refers to the acrylate and the corresponding methacrylate.

[0029]

[0028] The term "security document" refers to a document that is typically protected against counterfeiting or fraud by at least one security feature. Examples of security documents include, but are not limited to, documents of value and articles of value.

[0030]

[0029] The term "security feature" is used to describe an image, pattern, or graphic element that can be used for authentication purposes.

[0031]

[0030] Where this detailed description refers to "preferred" embodiments / features, combinations of these "preferred" embodiments / features shall also be deemed to be disclosed to the extent that such combinations of "preferred" embodiments / features make technical sense.

[0032]

[0031] The present invention provides a method for producing an optical effect layer (OEL) exhibiting one or more indicia (x30) on a substrate (x20), the OEL further exhibiting one or more indicia (x30) based on magnetically oriented non-spherical magnetic or magnetizable pigment particles.

[0033]

[0032] The method described herein comprises the step a) of applying a radical radiation curable coating composition comprising non-spherical magnetic or magnetizable pigment particles as described herein and one or more photoreactive compounds not absorbing in the range of about 375 nm to about 470 nm as described herein to the surface of a substrate (x20) as described herein to form a coating layer (x10) as described herein, said composition being in a first liquid state that allows its application as a layer and is not yet cured (i.e. wet), and the pigment particles are able to move and rotate within the layer. As the radical radiation curable coating composition described herein is to be provided on the surface of the substrate (x20), the radical radiation curable coating composition comprises at least a binder material and magnetic or magnetizable pigment particles, said composition being in a form that allows its processing in the desired printing or coating equipment. Preferably, said step a) is carried out by a printing process preferably selected from the group consisting of screen printing, gravure printing, flexography, intaglio printing (also referred to in the art as engraved copper printing, engraved steel die printing), pad printing and curtain coating, more preferably selected from the group consisting of intaglio printing, screen printing, gravure printing, pad printing and flexography, even more preferably selected from the group consisting of screen printing, gravure printing, pad printing and flexography. According to a preferred embodiment, step a) is carried out by a printing process selected from the group consisting of screen printing, gravure printing and flexography.

[0034]

[0033] The non-spherical magnetic or magnetizable pigment particles described in this specification are preferably prolate or oblate ellipsoidal, platelet-like or needle-like magnetic or magnetizable pigment particles, or a mixture of two or more thereof, more preferably platelet-like particles.

[0035]

[0034] The non-spherical magnetic or magnetizable pigment particles described herein are defined as having anisotropic reflectivity for incident electromagnetic radiation, for which the cured binder material is at least partially transparent, due to their non-spherical shape. The term "anisotropic reflectivity" as used herein indicates that the proportion of incident radiation from a first angle to a certain (viewing) direction (second angle) reflected by the particle is a function of the particle's orientation, i.e., a change in the particle's orientation relative to the first angle can cause a different magnitude of reflection in the viewing direction. Preferably, the non-spherical magnetic or magnetizable pigment particles described herein have anisotropic reflectivity for incident electromagnetic radiation in part or in the complete wavelength range of about 200 to about 2500 nm, more preferably about 400 to about 700 nm, such that a change in the particle's orientation results in a change in the reflection by the particle in a certain direction. As known by those skilled in the art, the magnetic or magnetizable pigment particles described herein differ from conventional pigments in that said conventional pigment particles exhibit the same color and reflectance independent of particle orientation, whereas the magnetic or magnetizable pigment particles described herein exhibit reflectance or color, or both, that are dependent on particle orientation.

[0036]

[0035] The radical radiation curable coating composition described herein and the coating layer (x10) described herein contain the non-spherical, preferably platelet-shaped magnetic or magnetizable pigment particles described herein in an amount of preferably from about 5% to about 40% by weight, more preferably from 10% to about 30% by weight, the weight percentages being based on the total weight of the radical radiation curable coating composition or coating layer (x10).

[0037]

[0036] In the OELs described herein, the magnetic or magnetizable pigment particles described herein are dispersed in a radical radiation curable coating composition comprising a cured binder material that fixes the orientation and position of the magnetic or magnetizable pigment particles. The binder material is at least in the cured or solid state (also referred to herein as the second state) and is at least partially transparent to electromagnetic radiation in the range of wavelengths from 200 nm to 2500 nm, a range of wavelengths typically referred to as the "optical spectrum" and including the infrared, visible, and UV portions of the electromagnetic spectrum. Thus, the particles contained in the cured or solid state binder material and their orientation dependent reflectance can be seen through the binder material at some wavelengths within this range. Preferably, the cured binder material is at least partially transparent to electromagnetic radiation in the range of wavelengths from 200 nm to 800 nm, more preferably from 400 nm to 700 nm. In this specification, the term "transmittance" indicates that the transmission of electromagnetic radiation through a 20 μm layer of the cured binder material present in the OEL (not including the non-spherical magnetic or magnetisable pigment particles, but including all other optional components of the OEL, if such components are present) is at least 50%, more preferably at least 60%, even more preferably at least 70% at the relevant wavelength. This can be determined by well-established test methods, for example by measuring the transmittance of a test piece of the cured binder material (without the non-spherical magnetic or magnetisable pigment particles) according to DIN 5036-3 (1979-11). If the OEL serves as a covert security feature, then typically technical means are required to detect the (completed) optical effect produced by the OEL in the respective lighting conditions including the selected non-visible wavelengths, said detection requiring that the wavelength of the incident radiation is selected outside the visible range, for example in the near UV range.

[0038] Suitable examples of non-spherical, preferably platelet-shaped, magnetic or magnetizable pigment particles as described herein include, but are not limited to, pigment particles comprising a magnetic metal selected from the group consisting of cobalt (Co), iron (Fe), and nickel (Ni); a magnetic alloy of iron, manganese, cobalt, nickel, or a mixture of two or more thereof; a magnetic oxide of chromium, manganese, cobalt, iron, nickel, or a mixture of two or more thereof; or a mixture of two or more thereof. The term "magnetic" with respect to metals, alloys, and oxides covers ferromagnetic or ferrimagnetic metals, alloys, and oxides. The magnetic oxides of chromium, manganese, cobalt, iron, nickel, or a mixture of two or more thereof may be pure or mixed oxides. Examples of magnetic oxides include, but are not limited to, hematite (Fe2O3), magnetite (Fe3O4), chromium dioxide (CrO2), magnetic ferrite (MFe2O4), magnetic spinel (MR2O4), magnetic hexaferrite (MFe 12 O 19 ), magnetic orthoferrite (RFeO3), and magnetic garnet M3R2(AO4)3, where M represents a divalent metal, R represents a trivalent metal, and A represents a tetravalent metal.

[0039]

[0038] Examples of non-spherical, preferably platelet-shaped, magnetic or magnetizable pigment particles described herein include, but are not limited to, pigment particles comprising a magnetic layer M consisting of one or more of a magnetic metal, such as cobalt (Co), iron (Fe), or nickel (Ni); and a magnetic alloy of iron, cobalt, or nickel, said magnetic or magnetizable pigment particles may be a multi-layer structure comprising one or more further layers. Preferably, the one or more further layers are a layer A independently of one or more selected from the group consisting of metal fluorides such as magnesium fluoride (MgF), silicon oxide (SiO), silicon dioxide (SiO), titanium oxide (TiO), and aluminum oxide (AlO), more preferably silicon dioxide (SiO); or a layer B independently of one or more selected from the group consisting of metals and metal alloys, preferably selected from the group consisting of reflective metals and reflective alloys, more preferably one or more selected from the group consisting of silver (Ag), aluminum (Al), chromium (Cr), and nickel (Ni), even more preferably aluminum (Al); or a combination of one or more layers A such as those mentioned above and one or more layers B such as those mentioned above. Representative examples of platelet-shaped magnetic or magnetizable pigment particles having such a multilayer structure include, but are not limited to, A / M multilayer structures, A / M / A multilayer structures, A / M / B multilayer structures, A / B / M / A multilayer structures, A / B / M / B multilayer structures, A / B / M / B / A / multilayer structures, B / M multilayer structures, B / M / B multilayer structures, B / A / M / A multilayer structures, B / A / M / B multilayer structures, B / A / M / B / A / multilayer structures, where layer A, magnetic layer M, and layer B are selected from those described above.

[0040]

[0039] The radical radiation curable coating composition described herein may comprise non-spherical, preferably platelet-shaped, optically variable magnetic or magnetisable pigment particles and / or non-spherical, preferably platelet-shaped, magnetic or magnetisable pigment particles not having optically variable properties. Preferably, at least a portion of the magnetic or magnetisable pigment particles described herein are constituted by non-spherical, preferably platelet-shaped, optically variable magnetic or magnetisable pigment particles. In addition to the overt security provided by the colour shifting properties of the optically variable magnetic or magnetisable pigment particles, which allow the easy detection, recognition and / or discrimination of articles or security documents bearing the inks, coating compositions or coating layers comprising the optically variable magnetic or magnetisable pigment particles described herein from their possible counterfeits using unaided human senses, the optical properties of the optically variable magnetic or magnetisable pigment particles may also be used as a machine-readable tool for the recognition of OELs. Thus, the optical properties of the optically variable magnetic or magnetisable pigment particles may simultaneously be used as a covert or semi-covert security feature in the authentication process in which the optical (e.g. spectral) properties of the pigment particles are analysed, thus improving counterfeit resistance.

[0041]

[0040] The use of non-spherical, preferably platelet-shaped, optically variable magnetic or magnetizable pigment particles in the coating layer to produce the OEL enhances the significance of the OEL as a security feature in security document applications, since such materials are reserved for the security document printing industry and are not generally commercially available.

[0042] As mentioned above, preferably at least a part of the non-spherical, preferably platelet-shaped, magnetic or magnetisable pigment particles is constituted by non-spherical, preferably platelet-shaped, optically variable magnetic or magnetisable pigment particles, which are preferably selected from the group consisting of magnetic thin film interference pigment particles, magnetic cholesteric liquid crystal pigment particles, interference coated pigment particles comprising a magnetic material and mixtures of two or more thereof.

[0043]

[0042] Magnetic thin film interference pigment particles are known to those skilled in the art and are disclosed, for example, in U.S. Pat. No. 4,838,648; WO 2002 / 073250; EP 0686675; WO 2003 / 000801; U.S. Pat. No. 6,838,166; WO 2007 / 131833; EP 2402401; WO 2019 / 103937; WO 2020 / 006286 and the documents cited therein. Preferably, the magnetic thin film interference pigment particles include pigment particles having a 5-layer Fabry-Perot multilayer structure, and / or pigment particles having a 6-layer Fabry-Perot multilayer structure, and / or pigment particles having a 7-layer Fabry-Perot multilayer structure, and / or pigment particles having a multilayer structure combining one or more multilayer Fabry-Perot structures.

[0044]

[0043] A preferred five-layer Fabry-Perot multilayer structure consists of a multilayer structure of absorber / dielectric / reflector / dielectric / absorber, where the reflector and / or absorber are also magnetic layers, preferably the reflector and / or absorber are magnetic layers comprising nickel, iron, and / or cobalt, and / or magnetic alloys comprising nickel, iron, and / or cobalt, and / or magnetic oxides comprising nickel (Ni), iron (Fe), and / or cobalt (Co).

[0045] A preferred six-layer Fabry-Perot multilayer structure consists of the following multilayer structure: absorber / dielectric / reflector / magnetic / dielectric / absorber.

[0046] A preferred seven-layer Fabry-Perot multilayer structure consists of an absorber / dielectric / reflector / magnetic / reflector / dielectric / absorber multilayer structure such as that disclosed in US Pat. No. 4,838,648.

[0047]

[0046] Preferred pigment particles having a multilayer structure combining one or more Fabry-Perot structures are described in WO 2019 / 103937, which consist of a combination of at least two Fabry-Perot structures, said two Fabry-Perot structures independently comprising a reflector layer, a dielectric layer and an absorber layer, the reflector and / or absorber layer each independently may comprise one or more magnetic materials and / or the magnetic layer is sandwiched between the two structures. WO 2020 / 006 / 286 and EP 3587500 disclose further preferred pigment particles having a multilayer structure.

[0048]

[0047] Preferably, the reflector layer described herein is selected from the group consisting of metals and metal alloys, preferably selected from the group consisting of reflective metals and reflective metal alloys, more preferably selected from the group consisting of aluminum (Al), silver (Ag), copper (Cu), gold (Au), platinum (Pt), tin (Sn), titanium (Ti), palladium (Pd), rhodium (Rh), niobium (Nb), chromium (Cr), nickel (Ni), and alloys thereof, even more preferably independently selected from one or more of the group consisting of aluminum (Al), chromium (Cr), nickel (Ni), and alloys thereof, even more preferably independently selected from aluminum (Al). Preferably, the dielectric layer is independently selected from the group consisting of metal fluorides such as magnesium fluoride (MgF2), aluminum fluoride (AlF3), cerium fluoride (CeF3), lanthanum fluoride (LaF3), sodium aluminum fluoride (e.g., Na3AlF6), neodymium fluoride (NdF3), samarium fluoride (SmF3), barium fluoride (BaF2), calcium fluoride (CaF2), lithium fluoride (LiF), and metal oxides such as silicon oxide (SiO), silicon dioxide (SiO2), titanium oxide (TiO2), aluminum oxide (Al2O3), more preferably one or more independently selected from the group consisting of magnesium fluoride (MgF2) and silicon dioxide (SiO2), and even more preferably magnesium fluoride (MgF2). Preferably, the absorber layer is independently selected from the group consisting of aluminum (Al), silver (Ag), copper (Cu), palladium (Pd), platinum (Pt), titanium (Ti), vanadium (V), iron (Fe), tin (Sn), tungsten (W), molybdenum (Mo), rhodium (Rh), niobium (Nb), chromium (Cr), nickel (Ni), metal oxides thereof, metal sulfides thereof, metal carbides thereof, and metal alloys thereof, more preferably selected from the group consisting of chromium (Cr), nickel (Ni), metal oxides thereof, and metal alloys thereof, even more preferably selected from the group consisting of chromium (Cr), nickel (Ni), and alloys thereof.Preferably, the magnetic layer comprises nickel (Ni), iron (Fe) and / or cobalt (Co); and / or a magnetic alloy comprising nickel (Ni), iron (Fe) and / or cobalt (Co); and / or a magnetic oxide comprising nickel (Ni), iron (Fe) and / or cobalt (Co). When magnetic thin film interference pigment particles comprising a seven-layer Fabry-Perot structure are preferred, it is particularly preferred that the magnetic thin film interference pigment particles comprise a seven-layer Fabry-Perot absorber / dielectric / reflector / magnetic / reflector / dielectric / absorber multilayer structure consisting of a Cr / MgF2 / Al / Ni / Al / MgF2 / Cr multilayer structure.

[0049]

[0048] The magnetic thin film interference pigment particles described herein are considered to be safe for human health and the environment, and may be, for example, multi-layer pigment particles based on a 5-layer Fabry-Perot multi-layer structure, a 6-layer Fabry-Perot multi-layer structure, a 7-layer Fabry-Perot multi-layer structure, and pigment particles having a multi-layer structure combining one or more Fabry-Perot multi-layer structures, said pigment particles comprising one or more magnetic layers comprising a magnetic alloy having a substantially nickel-free composition comprising about 40% to about 90% by weight iron, about 10% to about 50% by weight chromium, and about 0% to about 30% by weight aluminum. Representative examples of multi-layer pigment particles considered to be safe for human health and the environment can be found in EP 2402401, the entire contents of which are incorporated herein by reference.

[0050] Suitable magnetic cholesteric liquid crystal pigment particles exhibiting optically variable properties include, but are not limited to, magnetic single-layer cholesteric liquid crystal pigment particles and magnetic multi-layer cholesteric liquid crystal pigment particles. Such pigment particles are disclosed, for example, in WO 2006 / 063926, U.S. Pat. No. 6,582,781, and U.S. Pat. No. 6,531,221. WO 2006 / 063926 discloses monolayers and pigment particles obtained therefrom, with high brightness and color shifting properties, and with further specific properties such as magnetization. The disclosed monolayers and pigment particles are obtained therefrom by grinding the monolayers, and include three-dimensionally crosslinked cholesteric liquid crystal mixtures and magnetic nanoparticles. U.S. Pat. No. 6,582,781 and U.S. Pat. No. 6,410,130 disclose a method for producing a cholesteric liquid crystal pigment having a sequence A. 1 / B / A 2 The present invention discloses platelet-shaped cholesteric multi-layer pigment particles comprising: 1 and A 2 A and B may be the same or different and each comprises at least one cholesteric layer, B being an intermediate layer that absorbs all or part of the light transmitted by layers A1 and A2 and confers magnetic properties to said intermediate layer. US Patent No. 6,531,221 discloses platelet-shaped cholesteric multilayer pigment particles comprising the sequence A / B and optionally C, where A and C are absorbing layers containing pigment particles that impart magnetic properties and B is a cholesteric layer.

[0051]

[0050] Suitable interference coated pigment particles containing one or more magnetic materials include, but are not limited to, structures consisting of a substrate selected from the group consisting of a core coated with one or more layers, at least one or one or more layers of the core having magnetic properties. For example, suitable interference coated pigment particles include a core consisting of a magnetic material such as those described above, said core being coated with one or more layers consisting of one or more metal oxides, or they have a structure consisting of a core consisting of synthetic or natural mica, layered silicates (e.g., talc, kaolin, and sericite), glass (e.g., borosilicate), silicon dioxide (SiO2), aluminum oxide (Al2O3), titanium oxide (TiO2), graphite, and mixtures of two or more thereof. Furthermore, one or more further layers, such as colored layers, may be present.

[0052]

[0051] The non-spherical, preferably platelet-shaped, magnetic or magnetisable pigment particles described herein preferably have a size d50 (measured by direct optical particle size distribution) of from about 2 μm to about 50 μm.

[0053]

[0052] The non-spherical, preferably platelet-shaped, magnetic or magnetizable pigment particles described in this specification may be surface treated to protect them from possible deterioration of the coating compositions and coating layers and / or to promote their incorporation into said coating compositions and coating layers, typically using corrosion-inhibiting materials and / or wetting agents.

[0054]

[0053] As described herein, the method described herein comprises steps c) and e) of at least partially curing the coating layer (x10) to a second state in order to fix the magnetic or magnetisable pigment particles in their adopted position and orientation. In the first liquid state of the radical radiation curable coating composition, the magnetic or magnetisable pigment particles can move and rotate, and in the second state, the magnetic or magnetisable pigment particles are fixed and set by using a type of radical radiation curable coating composition. For example, the components of the radical radiation curable coating composition other than the non-spherical magnetic or magnetisable pigment particles may take the form of an ink or radical radiation curable coating composition, such as those used in security applications, e.g., in the printing of banknotes. The aforementioned first and second states are brought about by using a material that exhibits an increase in viscosity in response to exposure to electromagnetic radiation. That is, when the flowable binder material is cured or solidfied, said binder material changes to a second state and the non-spherical magnetic or magnetizable pigment particles are fixed in their current position and orientation and can no longer move or rotate within the binder material. By "at least partially curing the coating layer (x10)" as used herein, it is meant that the non-spherical, preferably platelet-shaped magnetic or magnetizable pigment particles are fixed / arrested in their adopted position and orientation and can no longer move or rotate (also referred to in the art as "pinning" the particles).

[0055]

[0054] The radical radiation curable coating composition used to prepare the coating layer (x10) described herein comprises non-spherical, preferably platelet-shaped, magnetic or magnetizable pigment particles as described herein, and one or more compounds that do not absorb in the range of about 375 nm to about 470 nm as described herein. Radiation curing, especially UV-Vis curing, advantageously leads to a momentary increase in the viscosity of the coating composition after exposure to radiation, thus preventing further migration of the pigment particles and, consequently, loss of information after the magnetic orientation step.

[0056]

[0055] A radically radiation curable coating composition comprising non-spherical, preferably platelet-shaped, magnetic or magnetizable pigment particles as described herein and one or more photoreactive compounds that do not absorb in the range of about 375 nm to about 470 nm as described herein is a radically curable composition. In other words, a radically radiation curable coating composition, preferably a UV-Vis curable coating composition, comprises monomers and / or oligomers that are radically curable compounds.

[0057]

[0056] The radically curable composition comprises one or more radically curable compounds which are cured by a free radical mechanism consisting of the activation by energy of one or more photoinitiators which liberate free radicals which then initiate the polymerization to form the binder. Preferably, the radically curable compounds are selected from (meth)acrylates, preferably from epoxy (meth)acrylates, (meth)acrylated oils, polyester and polyether (meth)acrylates, aliphatic or aromatic urethane (meth)acrylates, silicone (meth)acrylates, acrylic (meth)acrylates, and mixtures thereof.

[0058]

[0057] The radical radiation curable coating compositions described herein comprise one or more radically curable oligomers and one or more radically curable monomers, preferably selected from the group consisting of tri(meth)acrylates, tetra(meth)acrylates, and mixtures thereof, and optionally one or more reactive diluents which are radically curable monomers selected from the group consisting of mono(meth)acrylates, di(meth)acrylates, and mixtures thereof.

[0059]

[0058] According to one embodiment, the radically radiation curable coating composition preferably comprises one or more radically curable oligomers described herein in an amount of from about 25% to about 55% by weight, one or more radically curable monomers described herein in an amount of from about 10% to about 50% by weight, and optionally up to about 50% by weight of one or more reactive diluents described herein, the weight percentages being based on the total weight of the coating composition.

[0060]

[0059] A radically curable oligomer as used herein refers to a relatively high molecular weight oligomeric compound having a weight average molecular weight (MW) of ≥ 500 g / mol. The radically curable oligomer described herein is preferably a (meth)acrylate oligomer which may be branched or substantially linear, and the (meth)acrylate functional group or groups may be terminal groups and / or pendant side groups attached to the oligomer backbone, respectively. The term "(meth)acrylate" in the context of the present invention refers to acrylates and the corresponding methacrylates. Preferably, the radically curable oligomer is selected from the group consisting of (meth)acrylic-based oligomers, urethane (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether-based (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, and mixtures thereof, more preferably epoxy (meth)acrylate oligomers and mixtures thereof. The functionality of the oligomer is not limited, but is preferably 3 or less.

[0061] Suitable examples of epoxy (meth)acrylate oligomers include, but are not limited to, aliphatic epoxy (meth)acrylate oligomers, particularly mono(meth)acrylate, di(meth)acrylate, and tri(meth)acrylate, and aromatic epoxy (meth)acrylate oligomers.Suitable examples of aromatic epoxy (meth)acrylate oligomers include bisphenol-A (meth)acrylate oligomers, such as bisphenol-A mono(meth)acrylate, bisphenol-A di(meth)acrylate, and bisphenol-A tri(meth)acrylate, and alkoxylated (e.g., ethoxylated and propoxylated) bisphenol-A (meth)acrylate oligomers, such as alkoxylated bisphenol-A mono(meth)acrylate, alkoxylated bisphenol-A di(meth)acrylate, and alkoxylated bisphenol-A tri(meth)acrylate, preferably alkoxylated bisphenol-A di(meth)acrylate. A particularly suitable epoxy (meth)acrylate oligomer is sold under the name EBECRYL® 2959 by Allnex.

[0062]

[0061] The one or more tri(meth)acrylates described herein are preferably selected from the group consisting of trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, alkoxylated (especially ethoxylated or propoxylated) trimethylolpropane triacrylate, alkoxylated (especially ethoxylated or propoxylated) trimethylolpropane trimethacrylate, alkoxylated (especially ethoxylated or propoxylated) glycerin triacrylate, pentaerythritol triacrylate, alkoxylated (especially ethoxylated or propoxylated) pentaerythritol triacrylate and mixtures thereof, preferably selected from the group consisting of trimethylolpropane triacrylate, alkoxylated (especially ethoxylated or propoxylated) trimethylolpropane triacrylate, alkoxylated (especially ethoxylated or propoxylated) glycerin triacrylate, pentaerythritol triacrylate, and mixtures thereof. Particularly suitable trimethylolpropane triacrylate (CAS.15625-89-5) is sold under the name TMPTA by Allnex, under the name Miramer M300 by Rahn or under the name SR351 by Sartomer.

[0063]

[0062] The one or more tetra(meth)acrylates described in this specification are selected from ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, alkoxylated (e.g., ethoxylated and propoxylated) pentaerythritol tetra(meth)acrylate, and mixtures thereof, preferably selected from the group consisting of ditrimethylolpropane tetra(meth)acrylate, alkoxylated pentaerythritol tetra(meth)acrylate, and mixtures thereof.

[0064]

[0063] The radical radiation curable coating compositions described herein may further comprise 0 to 50% by weight, preferably 0 to 40%, more preferably 0 to 30%, of one or more reactive diluents as described herein, preferably selected from mono(meth)acrylates, di(meth)acrylates, and mixtures thereof, the weight percentages being based on the total weight of the radical radiation curable coating composition.

[0065]

[0064] Suitable mono(meth)acrylates may be selected from alkyl (meth)acrylates, cycloalkyl (meth)acrylates, benzyl (meth)acrylate, phenyl (meth)acrylate (including phenoxyalkyl (meth)acrylates such as phenoxyethyl acrylate), cyclic trimethylolpropane formal acrylate, tetrahydrofurfuryl acrylate, aliphatic urethane (meth)acrylates and alkoxylated (especially ethoxylated or propoxylated) compounds thereof.

[0066] Suitable di(meth)acrylates include, but are not limited to, ethylene glycol diacrylate, ethylene glycol dimethacrylate; 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate; 1,3-butanediol diacrylate, 1,3-butanediol dimethacrylate; 2-methyl-1,3-propanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate; 2-butyl-2-ethyl-1 ,3-Propanediol diacrylate, 1,6-Hexanediol diacrylate, 1,6-Hexanediol dimethacrylate;Neopentyl glycol diacrylate, neopentyl glycol dimethacrylate;1,9-Nonanediol diacrylate;1,9-Nonanediol dimethacrylate;1,10-Decanediol diacrylate, 1,10-Decanediol dimethacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hexanediol diacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hexanediol diacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hexanediol diacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hexanediol dimeth ...methacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hexanediol dimethacrylate, alkoxylated (especially ethoxylated and propoxylated) 1,6-Hex Sandiol diacrylate; propoxylated neopentyl glycol diacrylate; ethoxylated 2-methyl-1,3-propanediol diacrylate; tricyclodecane dimethanol diacrylate; diethylene glycol diacrylate, diethylene glycol dimethacrylate; dipropylene glycol diacrylate; triethylene glycol diacrylate, triethylene glycol dimethacrylate; tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate; polyethylene glycol 200 / 400 / 600 diacrylate, polyethylene glycol 200 / 400 / 600 dimethacrylate; ethoxylated (EO2 / EO3 / EO4 / EO10) bisphenol A diacrylate, and ethoxylated (EO2 / EO3 / EO4 / EO10) bisphenol A dimethacrylate. Particularly suitable tripropylene glycol diacrylate (CAS 42978-66-5) is sold by Allnex under the name TPGDA.

[0067]

[0066] The radical radiation curable coating compositions comprising the non-spherical, preferably platelet-shaped, magnetic or magnetisable pigment particles described herein may further comprise one or more colouring components selected from the group consisting of organic pigment particles, inorganic pigment particulates and organic dyes, and / or one or more additives. Examples of the latter include, but are not limited to, compounds and materials used to adjust the physical, rheological and chemical parameters of the coating composition, such as viscosity (e.g., solvents, thickeners and surfactants), consistency (e.g., anti-settling agents, fillers and plasticisers), foamability (e.g., defoamers), lubricity (waxes, oils), UV stability (light stabilizers), adhesion, antistatic properties, storage stability (polymerisation inhibitors). The additives described herein may be present in the coating composition in amounts and forms known in the art, including so-called nanomaterials, where at least one of the dimensions of the additive is in the range of 1-1000 nm.

[0068]

[0067] The radical radiation curable coating composition comprising the non-spherical, preferably platelet-shaped, magnetic or magnetisable pigment particles described herein may further comprise one or more labelling substances or identification additives selected from the group consisting of magnetic materials (different from the magnetic or magnetisable pigment particles described herein), luminescent materials, electroluminescent materials, up-converting materials, electrically conductive materials and infrared absorbing materials, and / or one or more machine-readable materials. As used herein, the term "machine-readable material" refers to a material exhibiting at least one unique property that is detectable by a device or machine and that can be included in said coating to provide a method for its detection and / or authentication to authenticate the coating or an article comprising said coating by use of a specific device.

[0069]

[0068] Preferably, the radical radiation curable coating compositions described herein are characterized by a viscosity of from about 200 mPas to about 1500 mPas at 25°C, measured using a Brookfield Viscometer (Model "DV-I Prime") equipped with spindle S27 at 100 rpm.

[0070]

[0069] The radical radiation curable coating compositions described herein may be prepared by dispersing or mixing the magnetic or magnetizable pigment particles described herein and one or more additives, when present, in the presence of a binder material described herein to form a liquid composition. When present, the one or more photoinitiators may be added to the composition during the dispersing or mixing step of all the other ingredients or may be added at a later stage, i.e., after formation of the liquid coating composition.

[0071] The method described herein further comprises, after step a) as described herein, step b) of applying at least partially onto the coating layer (x10) as described herein, a top-coating composition as described herein, which is applied in the form of one or more indicia (x30) as described herein and which partially overlaps (i.e. overlaps in at least one area) the coating layer (x10) as described herein, the radical radiation curable coating composition of the coating layer (x10) being in a wet unpolymerized state and the magnetic or magnetizable pigment particles being free to move and rotate.

[0072]

[0071] The term "indicia" as used herein means continuous and discontinuous layers of markings or signs or patterns of identification. Preferably, the one or more indicia (x30) described herein are selected from the group consisting of codes, symbols, alphanumeric symbols, motifs, geometric patterns (e.g., circles, triangles, and regular or irregular polygons), letters, words, numbers, logos, figures, portraits, and combinations thereof. Examples of codes include coded marks such as coded alphanumeric data, one-dimensional barcodes, two-dimensional barcodes, QR codes, data matrices, and IR-readable codes. The one or more indicia (x30) described herein may be solid indicia and / or raster indicia.

[0073]

[0072] The topcoating composition described herein is applied in the form of one or more indicia (x30) as described herein by an application process, more preferably a non-contact fluid micro-dispensing process preferably selected from the group consisting of spray coating, aerosol inkjet printing, electrohydrodynamic printing, slot-die coating, and inkjet printing, even more preferably an inkjet printing process, said non-contact fluid micro-dispensing printing process being a variable information printing method allowing the unique creation of one or more indicia (x30) on or in an optical effect layer (OEL) as described herein. The application process is selected as a function of the design and resolution of the indicia or indicia to be created.

[0074] Inkjet printing may be advantageously used to create optical effect layers (OELs) exhibiting one or more of the indicia described herein, including variable halftones. Inkjet halftone printing is a reproduction technique that simulates continuous tone images containing an infinite number of colors or shades of gray by the application of variable inkjet coverage or basis weight.

[0075]

[0074] Spray coating is a technique in which a fine aerosol is formed by forcing a composition through a nozzle. A carrier gas and an electrostatic charge may be involved to function to direct the aerosol onto the surface to be printed. Spray printing makes it possible to print spots and lines. Compositions suitable for spray printing typically have a viscosity of about 10 mPa.s to about 1 Pa.s at 15°C (1000s -1 ) The resolution of spray coating printing is in the millimeter range. Spray printing is described, for example, in F. C. Krebs, Solar Energy Materials & Solar Cells (1009), 93, p. 407.

[0076] Aerosol inkjet printing (AJP) is a new non-contact direct-write approach aimed at producing fine features on a wide range of substrates. AJP is compatible with a wide range of materials and freeform deposition, allowing high resolution (on the order of about 10 micrometers) along with relatively large separation distances (e.g., 1-5 mm) in addition to orientation independence. The technique involves aerosol generation using ultrasonic or pneumatic atomizers, typically with a flow rate of about 1 mPa.s to about 1 Pa.s at 15°C (1000 s -1 Aerosols are generated from compositions having a viscosity of about 100 nm. Aerosol jet printing is described, for example, in NJ Wilkinson et al., The International Journal of Advanced Manufacturing Technology (1999) 105:4599-4619.

[0077] Electrohydrodynamic inkjet printing is a high resolution inkjet printing technique. Electrohydrodynamic inkjet printing uses an externally applied electric field to manipulate droplet size, ejection times, and placement on a substrate to obtain higher resolution than conventional inkjet printing while maintaining high production speed. The resolution of electrohydrodynamic inkjet printing is about two orders of magnitude higher than conventional inkjet printing techniques, and therefore it can be used to orient nanoscale and microscale patterns. Electrohydrodynamic inkjet printing may be used in both DOD or continuous modes. Electrohydrodynamic inkjet printing compositions typically have a viscosity of about 1 mPa.s to about 1 Pa.s at 15°C (1000 s -1 ) The electrohydrodynamic inkjet printing technique is described, for example, in PV Raje and NC Murmu, International Journal of Emerging Technology and Advanced Engineering, (1014), 4(5), pp. 174-183.

[0078] Slot die coating is a one-dimensional coating technique. Slot die coating allows for the coating of stripes of material well suited for producing multi-layer coatings in which stripes of different materials are layered on top of each other. Alignment of the pattern is provided by moving the coating head along a direction perpendicular to the direction of web movement. A slot die coating head includes a mask that defines a slot in the coating head through which the slot die coating ink is dispersed. An example of a slot die coating head is described in FCKrebs, Solar Energy Materials & Solar Cells (1009), 93, pp. 405-406. Compositions suitable for slot die coating typically have a viscosity of about 1 mPa.s to about 20 mPa.s at 15°C (1000s -1 ) viscosity.

[0079] According to one embodiment, the top coating composition described herein is printed in the form of one or more indicia (x30) as described herein by an inkjet printing process, preferably a continuous inkjet (CI) printing process, or a drop-on-demand (DOD) inkjet printing process, more preferably a drop-on-demand (DOD) inkjet printing process. Drop-on-demand (DOD) printing is a non-contact printing process, where droplets are simply created when needed for printing, generally by an ejection mechanism, rather than by destabilizing the jet. Depending on the mechanism used in the print head to create the droplets, DOD printing can be performed by a variety of methods, including piezoelectric impulse, thermal jet, valve jet (from about 1 mPa.s to about 1 Pa.s at 15°C (1000 s -1 ) viscous), and electrostatic processes.

[0080]

[0079] The topcoating compositions described herein comprise one or more radically curable compounds selected from the group consisting of mono(meth)acrylates, such as those described herein, di(meth)acrylates, tri(meth)acrylates, tetra(meth)acrylates, such as those described herein, and mixtures thereof.

[0081] According to one embodiment, the top-coating composition described herein comprises a radically curable compound, e.g. one or more monomers and / or oligomers as described herein for the radically radiation curable coating composition comprising magnetic or magnetisable pigment particles as described herein. For the embodiment in which the top-coating composition is applied by an inkjet printing process, said top-coating composition may further comprise conventional additives and ingredients such as wetting agents, defoamers, surfactants, (co)solvents and mixtures thereof used in the field of radiation curable inkjet.

[0082]

[0081] The top coating compositions described herein may further comprise one or more labeling substances or taggants and / or one or more machine-readable materials, such as those described for the radical radiation curable coating compositions comprising the non-spherical magnetic or magnetizable pigment particles described herein, provided that the size of the substances, taggants or machine-readable materials is suitable for the application process described herein.

[0083]

[0082] The method for preparing an optical effect layer (OEL) exhibiting one or more indicia (x30) thereof comprises at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) under said one or more indicia (x30) with a LED curing unit (x50) and at least partially curing the coating layer (x10) with a curing unit (x60) emitting at least between 250 nm and 320 nm, allowing selective curing of the one or more indicia (x30) and the coating layer (x10) at different stages of the method requiring specific combinations. Thus, the one or more photoreactive compounds that do not absorb in the range of about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) and the one or more compounds that absorb in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) are selected according to one of the combinations described in the following embodiments.

[0084] According to a first embodiment, the one or more photoreactive compounds not absorbing in the range from about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) are alpha-hydroxyketones, preferably 2-hydroxy-2-methylpropiophenone (e.g. CAS 7473-98-5, sold by IGM Resins under the name Omnirad 1173); 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (e.g. CAS 106797-53-9, sold by IGM Resins under the name Omnirad 2959); 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (e.g. CAS 106797-53-9, sold by IGM Resins under the name Omnirad 127); 474510-57-1;(1-hydroxycyclohexyl)phenylmethanone (e.g., CAS 947-19-3, sold by IGM Resins under the name Omnirad 481);2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (e.g., CAS 71868-15-0, sold by IGM Resins under the name ESACURE KIP 160);1-[2,3-dihydro-1-[4-(1-hydroxy-2-methyl-1-oxopropyl)phenyl]-1,3,3-trimethyl-1H-inden-5-yl]-2-hydroxy-2-methyl-1-propanone (CAS 135452-43-6;ar-(1-hydroxy-2-methyl-1-oxopropyl)(1-methylethenyl)-benzene homopolymer (e.g. CAS 163702-01-0, sold by IGM Resins under the name ESACURE KIP 150);α-(1,1-dimethyl-2-oxo-2-phenylethyl)-ω-hydroxy-poly(oxy-1,2-ethanediyl) (9CI) (e.g. CAS 554449-21-7, sold by Double Bond Chemical under the name DoubleCure® 73W);Polymeric alpha-hydroxy-ketones (for example CAS 1842314-75-3 sold by DoubleBond under the name CHIVACURE® 300). More preferably, the alpha-hydroxyketone of the radical radiation curable coating composition of step a) of said first embodiment is selected from the group consisting of 2-hydroxy-2-methylpropiophenone (CAS 7473-98-5); 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (CAS 106797-53-9); 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (CAS 474510-57-1); (1-hydroxycyclohexyl)phenylmethanone (CAS 947-19-3); 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one (CAS 71868-15-0); 1-[2,3-dihydro-1-[4-(1-hydroxy-2-methyl-1-oxopropyl)phenyl]-1,3,3-trimethyl-1H-inden-5-yl]-2-hydroxy-2-methyl-1-propanone (CAS 135452-43-6); ar-(1-hydroxy-2-methyl-1-oxopropyl)(1-methylethenyl)-benzene homopolymer (CAS 163702-01-0); and mixtures thereof. More preferably, the alpha-hydroxyketone of the radiation curable coating composition of step a) of the first embodiment is selected from the group consisting of 2-hydroxy-2-methylpropiophenone (CAS 7473-98-5); 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (CAS 106797-53-9); and mixtures thereof.

[0085] According to said first embodiment, the one or more compounds absorbing in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) are selected from the group consisting of acylphosphine oxide compounds, alpha-amino-ketone compounds, mixtures of one or more benzophenone compounds (different from those of the radical radiation curable coating composition of step a)) and one or more amine compounds, glyoxylate compounds (optionally with one or more amine compounds), benzyl ketal compounds (different from those of the radical radiation curable coating composition of step a)), oxime ester compounds, titanocene compounds, mixtures of one or more thioxanthone compounds and one or more amine compounds, mixtures of one or more coumarin compounds and one or more amine compounds, mixtures of one or more camphorquinone compounds and one or more amine compounds; and mixtures thereof.

[0086]

[0085] Preferably, the acylphosphine oxide compound is selected from the group consisting of (1,4,6-trimethylbenzoyl)diphenylphosphine oxide (e.g. CAS 75980-60-8, sold under the name Omnirad TPO by IGM Resins); 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (e.g. CAS 84434-11-7, sold under the name Omnirad TPO-L by IGM Resins); phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (e.g. CAS 162881-26-7, sold under the name Omnirad 819 by IGM Resins); bis(1,6-dimethoxybenzoyl)(1,4,4-trimethylpentyl)phosphine oxide (e.g. CAS 162881-26-7, sold under the name Omnirad 819 by IGM Resins); 145052-34-2); ethyl (3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate (e.g., CAS 1539267-56-5 sold by Lambson under the name SpeedCure XKm); α,α',α''-1,2,3-propanetriyltris[ω-[[phenyl(1,4,6-trimethylbenzoyl)phosphinyl]oxy]-poly(oxy-1,2-ethanediyl) (e.g., CAS 1834525-17-5 sold by Rahn under the name Omnipol TP); and mixtures thereof.More preferably, the acylphosphine oxide compound is selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7); phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7); bis(1,6-dimethoxybenzoyl)(1,4,4-trimethylpentyl)phosphine oxide (CAS 145052-34-2); ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate (CAS 1539267-56-5); α,α′,α″-1,2,3-propanetriyltris[ω-[[phenyl(1,4,6-trimethylbenzoyl)phosphinyl]oxy]-poly(oxy-1,2-ethanediyl) (CAS 1834525-17-5); and mixtures thereof. Even more preferably, the acylphosphine oxide compound is selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7); phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7); and mixtures thereof.

[0087]

[0086] Preferably, the alpha-amino-ketone compound is 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone (e.g., CAS 119313-12-1, sold by IGM Resins under the name Omnirad 248); 2-(4-methylbenzyl)-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone (e.g., CAS 119344-86-4, sold by IGM Resins under the name Omnirad 379); 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (e.g., CAS 119344-86-4, sold by IGM Resins under the name Omnirad 4817); 71868-10-5; 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (e.g., GENOCURE *FMP sold by Rahn, CAS 2020359-04-8); α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (e.g. CAS 886463-10-1 sold by IGM Resins under the name Omnipol 910); and mixtures thereof. More preferably, the alpha-amino-ketone compound is 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (CAS 71868-10-5); 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl-1-propanone (CAS 2020359-04-8); α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1); and mixtures thereof.Even more preferably, the alpha-amino-ketone compound is selected from the group consisting of 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (CAS 71868-10-5); 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (CAS 2020359-04-8); and α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1); and mixtures thereof.

[0088]

[0087] Preferably, the benzophenone compound is selected from the group consisting of [1,1'-biphenyl]-4-ylphenylmethanone (e.g., CAS 2128-93-0 sold by IGM Resins under the name Omnirad 4PBZ); 4-(4-methylphenylthio)benzophenone (e.g., CAS 83846-85-9 sold by Lambson under the name SpeedCure BMS); 4,4'-bis(diethylamino)benzophenone (e.g., CAS 90-93-7 sold by Lambson under the name SpeedCure EMK); 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (e.g., CAS 272460-97-6 sold by IGM Resins under the name ESACURE 1001M); and mixtures thereof. More preferably, the benzophenone compound is selected from the group consisting of [1,1'-biphenyl]-4-ylphenylmethanone (CAS 2128-93-0); 4-(4-methylphenylthio)benzophenone (CAS 83846-85-9); 4,4'-bis(diethylamino)benzophenone (CAS 90-93-7); 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6); and mixtures thereof. Even more preferably, the benzophenone compound is selected from the group consisting of 4,4'-bis(diethylamino)benzophenone (CAS 90-93-7); and 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6); and mixtures thereof.

[0089]

[0088] Preferably, the glyoxylate compound is selected from the group consisting of 2-oxo-2-phenylacetic acid methyl ester (e.g., CAS 15206-55-0, sold by IGM Resins under the name Omnirad MBF); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (e.g., CAS 211510-16-6, sold by IGM Resins under the name Omnirad 754); α-(1-oxo-2-phenylacetyl)-ω-[(1-oxo-2-phenylacetyl)oxy]-poly(oxy-1,4-butanediyl) (e.g., CAS 1313205-82-1, sold by IGM Resins under the name Omnipol 2712); and mixtures thereof. More preferably, the glyoxylate compound is selected from the group consisting of 2-2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS 211510-16-6); and mixtures thereof.

[0090]

[0089] Preferably, the benzyl ketal compound is 2,2-dimethoxy-1,2-diphenylethan-1-one (for example CAS 24650-42-8 sold by Rahn under the name Omnirad BDK).

[0091]

[0090] Preferably, the oxime ester compound is 5-[[4-(1-methylethyl)phenyl]thio]-1H-indene-1,2(3H)-dione 2-(O-acetyloxime) (e.g. CAS 1546704-29-3 sold by IGM Resins under the name Omnirad 1312); 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyloxime) (e.g. CAS 253585-83-0 sold by BASF under the name IRGACURE® OXE01); 3-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-propanedione-2-(O-benzoyloxime) (CAS 1196481-09-0; 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (e.g. CAS 1206525-75-8 sold by Lambson under the name SpeedCure 8001); 1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime) (e.g. CAS 478556-66-0 sold by BASF under the name IRGACURE® OXE02); 3-cyclopentyl-1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]-1-propanone-1-(O-acetyloxime) (e.g. CAS 478556-66-0 sold by BASF under the name SpeedCure 8002). 1227375-90-7); 1,8-bis(O-acetyloxime)-1,8-bis[9-(1-ethylhexyl)-6-nitro-9H-carbazol-3-yl]-1,8-octanedione (e.g., CAS 1241377-23-0, sold by ADEKA under the name ADEKA NCI-831); and mixtures thereof.More preferably, the oxime ester compound is 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyloxime) (CAS 253585-83-0); 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8); 1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime) (CAS 478556-66-0); 3-cyclopentyl-1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]-1-propanone-1-(O-acetyloxime) (CAS 1227375-90-7);1,8-bis(O-acetyloxime)-1,8-bis[9-(1-ethylhexyl)-6-nitro-9H-carbazol-3-yl]-1,8-octanedione (CAS 1241377-23-0);and mixtures thereof.Even more preferably, the oxime ester compound is 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8).

[0092]

[0091] Preferably, the titanocene compound is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (for example CAS 125051-32-3 sold by IGM Resins under the name Omnirad 784).

[0093]

[0092] Preferably, the thioxanthone compound is 2-isopropyl-9H-thioxanthen-9-one (e.g., CAS 5495-84-1, sold by Lambson under the name SpeedCure 2-ITX or by IGM Resins under the name Omnirad ITX); 4-(1-methylethyl)-9H-thioxanthen-9-one (CAS 83846-86-0); 2,4-diethyl-9H-thioxanthen-9-one (e.g., CAS 82799-44-8, sold by IGM Resins under the name Omnipol TX); 2-chloro-9H-thioxanthen-9-one (e.g., CAS 86-39-5, sold by Lambson); 1-chloro-4-propoxy-9H-thioxanthen-9-one (e.g., CAS 86-39-5, sold by Lambson under the name SpeedCure CPTX). 142770-42-1;1,3-di[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane (e.g. CAS 142770-42-1, sold by Lambson under the name SpeedCure 7010 / 710L) 1003567-83-6;2-[2-[1-[2-[[2-(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxy]-2-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxymethyl]propoxy]ethoxy]ethoxy]ethyl prop-2-enoate (e.g. CAS 1427388-03-1 sold by IGM Resins under the name Omnipol 3 TX);α-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]-ω-[[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-poly(oxy-1,4-butanediyl) (CAS 813452-37-8);2-Thioxanthonyloxyacetic acid (e.g., CAS 84434-05-9, sold by Lambson under the name SpeedCure CMTX); α-[(9-oxo-9H-thioxanthen-4-yl)carbonyl]-ω-[[(9-oxo-9H-thioxanthen-4-yl)carbonyl]oxy]-poly(oxy-1,2-ethanediyl) (e.g., CAS 1258512-68-3, sold by Lambson under the name SpeedCure 7008); and their oligomeric and polymeric compounds (e.g., GENOPOL; *TX-1 by Rahn, and, for example, CAS 2055335-46-9 sold by Rahn under the name GENOPOL® TX-2); and mixtures thereof. More preferably, the thioxanthone compound is 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1); 4-(1-methylethyl)-9H-thioxanthen-9-one (CAS 83846-86-0); 2,4-diethyl-9H-thioxanthen-9-one (CAS 82799-44-8); 1-chloro-4-propoxy-9H-thioxanthen-9-one (CAS 142770-42-1); 1,3-di[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane (CAS 1003567-83-6;2-[2-[1-[2-[[2-(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxy]-2-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxymethyl]propoxy]ethoxy]ethoxy]ethyl prop-2-enoate (CAS 1427388-03-1);α-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]-ω-[[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-poly(oxy-1,4-butanediyl) (CAS 813452-37-8); their oligomeric and polymeric compounds (CAS 515139-51-2 and 2055335-46-9); and mixtures thereof. Even more preferably, the thioxanthone compound is 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1).

[0094] Preferably, the coumarin compound is 3-(4-C 10 -C 13-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (for example, CAS 2243703-91-3, sold by IGM Resins under the name ESACURE 3644).

[0095] Preferably, the camphorquinone compound is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione (e.g., GENOCURE * CQ, sold by Rahn (CAS 10373-78-1).

[0096]

[0095] The one or more amine compounds of the top curable coating composition of step b), if present, is preferably 2-[(1-hydroxyethyl)(methyl)amino]ethan-1-ol (e.g., GENOCURE * CAS 105-59-9, sold by Rahn under the name MDEA; 4-ethoxycarbonyl-N,N-dimethylaniline (e.g., GENOCURE *CAS 10287-53-3 sold by Rahn under the name EPD; 3-methylbutyl 4-(dimethylamino)benzoate (e.g. CAS 21245-01-2 sold by IGM Resins under the name Omnirad IADB); 2-ethylhexyl 4-(dimethylamino)benzoate (e.g. CAS 21245-02-3 sold by IGM Resins under the name Omnirad DMB); or 2-dimethylaminoethyl benzoate (CAS 2208-05-1); 2-butoxyethyl 4-(dimethylamino)benzoate (e.g. CAS 67362-76-9 sold by Lambson under the name SpeedCure BEDB); 1,1'-[(methylimino)di-2,1-ethanediyl]bis[4-(dimethylamino)benzoate] (e.g. CAS 21245-01-2 sold by IGM Resins under the name ESACURE A198) by Lamberti. 925246-00-0);butoxy polypropylene glycol 4-dimethylaminobenzoate (e.g., CAS 223463-45-4, sold by Lambson under the name SpeedCure PDA);poly(ethylene glycol) bis(p-dimethylaminobenzoate) (e.g., CAS 71512-90-8, sold by IGM Resins under the name Omnipol ASA);polymers of 4-(dimethylamino)benzoate with oxirane and 2-methyl-oxirane (CAS 1003557-17-2);polymers of 4-(dimethylamino)benzoate with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol and oxirane (e.g., GENOPOL *AB-2 sold by Rahn, CAS 2067275-86-7; α-hydro-ω-[[4-(dimethylamino)benzoyl]oxy]-poly[oxy(methyl-1,2-ethanediyl)] and 2,2-bis(hydroxymethyl)-1,3-propane tetra-ether (4:1) (CAS 1003567-84-7); reaction products of N-methylbenzenamine and 1,1'-[2-ethyl-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-1,3-propanediyl]-2-propenoate ester (e.g., CAS 2407644-16-8 sold by IGM Resins under the name Omnipol 894); and mixtures thereof.More preferably, the one or more amine compounds of the top curable coating composition of step b), if present, are preferably 2-[(1-hydroxyethyl)(methyl)amino]ethan-1-ol (CAS 105-59-9); 3-methylbutyl 4-(dimethylamino)benzoate (CAS 21245-01-2); 2-dimethylaminoethyl benzoate (CAS 2208-05-1); 2-butoxyethyl 4-(dimethylamino)benzoate (CAS 67362-76-9); 1,1'-[(methylimino)di-2,1-ethanediyl]bis[4-(dimethylamino)benzoate] (CAS 925246-00-0); butoxypolypropylene glycol 4-dimethylaminobenzoate (CAS 223463-45-4); poly(ethylene glycol)bis(p-dimethylaminobenzoate) (CAS 71512-90-8;Polymers of 4-(dimethylamino)benzoate with oxirane and 2-methyl-oxirane (CAS 1003557-17-2);Polymers of 4-(dimethylamino)benzoate with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol and oxirane (CAS 2067275-86-7);Tetra-ether (4:1) of α-hydro-ω-[[4-(dimethylamino)benzoyl]oxy]-poly[oxy(methyl-1,2-ethanediyl)] and 2,2-bis(hydroxymethyl)-1,3-propane (CAS 1003567-84-7);Reaction products of N-methylbenzenamine with 1,1'-[2-ethyl-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-1,3-propanediyl]-2-propenoate ester (CAS 2407644-16-8); and mixtures thereof. Even more preferably, the one or more amine compounds of the top curable coating composition of step b) of said first embodiment is poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8).

[0097]

[0096] Preferred examples of combinations of one or more photoreactive compounds that do not absorb in the range of about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) and one or more compounds that absorb in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) of the first embodiment are: The alpha-hydroxyketone of the radical radiation curable coating composition of step a) and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of 2-hydroxy-2-methylpropiophenone (CAS 7473-98-5); 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (CAS 106797-53-9); and mixtures thereof. i-1″) acylphosphine oxide compounds selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7); phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7); and mixtures thereof; i-2'') 2-Methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (CAS 71868-10-5); 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (CAS 2020359-04-8); and α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1); and mixtures thereof; i-3″) one or more amine compounds selected from the group consisting of 4,4′-bis(diethylamino)benzophenone (CAS 90-93-7); and 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6); and mixtures thereof, and poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8), i-4″) one or more amine compounds selected from the group consisting of 2-2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0); 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS 211510-16-6); and mixtures thereof, optionally poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8), i-5'') 2,2-dimethoxy-1,2-diphenylethan-1-one (CAS 24650-42-8), a benzil ketal compound; i-6'') 4-Cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8) is an oxime ester compound; i-7'') the titanocene compound bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3); i-8″) a thioxanthone compound which is 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1); and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8); i-9'')3-(4-C 10 -C 13-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (CAS 2243703-91-3); and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8), i-10'') a camphorquinone compound which is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione (CAS 10373-78-1); and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8), and i-11'') mixtures thereof.

[0098] According to a second embodiment, the one or more photoreactive compounds not absorbing in the range from about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) are a mixture of one or more benzophenone compounds different from the benzophenone compounds of the top curable coating composition of step b) of the first embodiment, and one or more amine compounds such as those described for the one or more amine compounds of the top curable coating composition of step b) of the first embodiment, preferably diphenylmethanone (e.g. CAS 119-61-9 sold by IGM Resins under the name Omnirad BP); 2-methylbenzophenone (CAS 131-58-8); (4-methylphenyl)phenylmethanone (e.g. CAS 134-84-9 sold by IGM Resins under the name Omnirad 4MBZ); 2,4,6-trimethylbenzophenone (CAS 954-16-5); 4-hydroxybenzophenone laurate (e.g. CAS 131-58-8 sold by IGM Resins under the name Omnirad 4MBZ); CAS 142857-24-7 sold by IGM Resins under the name 4HBL; α-(1-oxo-2-propenyl)-ω-(4-benzoylphenoxy)-poly(oxy-1,2-ethanediyl) (9CI) (e.g. CAS 478549-43-8 sold by BCH Bruhl under the name LoMiCure 450); polymers of 2-benzoylbenzoate with oxirane and 2-methyl-oxirane (CAS 1003557-16-1); 2-benzoylbenzoic acid methyl ester (e.g. GENOCURE *CAS 606-28-0 sold by Rahn under the name MBB; 2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate (e.g. CAS 75005-95-7 sold by IGM Resins under the name Omnirad 991); α-(1-benzoylbenzoyl)-ω-[(1-benzoylbenzoyl)oxy]-poly(oxy-1,2-ethanediyl) (e.g. CAS 1246194-73-9 sold by IGM Resins under the name Omnipol 2702); [α-[(4-benzoylphenoxy)acetyl]-ω-[[2-(4-benzoylphenoxy)acetyl]oxy]-poly(oxy-1,4-butanediyl) (e.g. CAS 1246194-73-9 sold by IGM Resins under the name Omnipol BP 515136-48-8;1,3-di[[α-2-(phenylcarbonyl)benzoylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-2-(phenylcarbonyl)benzoylpoly[oxy(1-methylethylene)]]oxymethyl]propane (CAS 1003567-82-5);polymeric benzophenone derivatives (e.g., GENOPOL *BP-2 sold by Rahn, or EBECRYL® P39 sold by Allnex, or PolyQ® 102 sold by Double Bond Chemical (CAS 2055335-45-8); and mixtures thereof. More preferably, the benzophenone compound of the radical radiation curable coating composition of step a) of the second embodiment is selected from the group consisting of diphenylmethanone (CAS 119-61-9); (4-methylphenyl)phenylmethanone (CAS 134-84-9); 2,4,6-trimethylbenzophenone (CAS 954-16-5); 2-benzoylbenzoic acid methyl ester (CAS 606-28-0); 2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate (CAS 75005-95-7); α-(1-benzoylbenzoyl)-ω-[(1-benzoylbenzoyl)oxy]-poly(oxy-1,2-ethanediyl) (CAS 1246194-73-9);[α-[(4-benzoylphenoxy)acetyl]-ω-[[2-(4-benzoylphenoxy)acetyl]oxy]-poly(oxy-1,4-butanediyl) (CAS 515136-48-8); and polymeric benzophenone derivatives such as, for example, CAS 2055335-45-8. Even more preferably, the benzophenone compound of the radical radiation curable coating composition of step a) of the second embodiment is selected from the group consisting of diphenylmethanone (CAS 119-61-9);2,4,6-trimethylbenzophenone (CAS 954-16-5);(4-methylphenyl)phenylmethanone (CAS 134-84-9);2-benzoylbenzoic acid methyl ester (CAS 606-28-0).

[0099] According to said second embodiment, the one or more compounds absorbing in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) may be an acylphosphine oxide compound such as described herein for the top curable coating composition of step b) of the first embodiment, an alpha-amino-ketone compound such as described herein for the top curable coating composition of step b) of the first embodiment, a benzophenone compound such as described herein for the top curable coating composition of step b) of the first embodiment, a glyoxylate compound (optionally with one or more amine compounds such as described herein for the top curable coating composition of step b) of the first embodiment, benzyl ketal compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, oxime ester compounds, titanocene compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, thioxanthone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, coumarin compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, camphorquinone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment; and mixtures thereof.

[0100]

[0099] Preferred examples of combinations of one or more photoreactive compounds that do not absorb in the range of about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) and one or more compounds that absorb in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) of the second embodiment are: The one or more benzophenone compounds of the radical radiation curable coating composition of step a) are selected from the group consisting of diphenylmethanone (CAS 119-61-9); 2,4,6-trimethylbenzophenone (CAS 954-16-5); (4-methylphenyl)phenylmethanone (CAS 134-84-9); 2-benzoylbenzoic acid methyl ester (CAS 606-28-0); the one or more amine compounds are poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8); and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: ii-1″) acylphosphine oxide compounds selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7); phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7); ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate (CAS 1539267-56-5); and mixtures thereof. ii-2″) alpha-amino-ketone compounds selected from the group consisting of 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (CAS 2020359-04-8); and α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1); and mixtures thereof. ii-3″) a benzophenone compound different from the benzophenone compound of the radical radiation curable coating composition of step a) selected from the group consisting of [1,1′-biphenyl]-4-ylphenylmethanone (CAS 2128-93-0); 4-(4-methylphenylthio)benzophenone (CAS 83846-85-9); 4,4′-bis(diethylamino)benzophenone (CAS 90-93-7); 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6); and mixtures thereof, ii-4'') Glyoxylate compound which is 2-2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0); ii-5'') 2,2-dimethoxy-1,2-diphenylethan-1-one (CAS 24650-42-8) benzyl ketal compound; ii-6'') an oxime ester compound which is 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8); ii-7'') a titanocene compound, which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3); ii-8'') A thioxanthone compound, which is 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1). ii-9'')3-(4-C 10 -C 13 -benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (CAS 2243703-91-3), a coumarin compound; ii-10'') a camphorquinone compound which is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione (CAS 10373-78-1), and ii-11'') Mixtures thereof.

[0101] According to a third embodiment, the one or more photoreactive compounds of the radical radiation curable coating composition of step a) that do not absorb in the range of about 375 nm to about 470 nm are benzyl ketal compounds different from the benzyl ketal compound of the top curable coating composition of step b) of said third embodiment, preferably said benzyl ketal compound is 2,2-diethoxyacetophenone (e.g., GENOCURE * DEAP is a CAS 6175-45-7 sold by Rahn under the name DEAP.

[0102] According to said third embodiment, the one or more compounds absorbing in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) comprises an acylphosphine oxide compound such as described herein for the top curable coating composition of step b) of the first embodiment, an alpha-amino-ketone compound such as described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more benzophenone compounds such as described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as described herein for the top curable coating composition of step b) of the first embodiment, a glyoxylate compound such as described herein for the top curable coating composition of step b) of the first embodiment (optionally one or more amine compounds such as described herein for the top curable coating composition of step b) of the first embodiment. a benzyl ketal compound such as those described herein for the top curable coating composition of step b) of the first embodiment, an oxime ester compound such as those described herein for the top curable coating composition of step b) of the first embodiment, a titanocene compound such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more thioxanthone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more coumarin compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment,a mixture of one or more camphorquinone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment; and mixtures thereof.

[0103]

[0102] Preferred examples of combinations of one or more photoreactive compounds that do not absorb in the range of about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) and one or more compounds that absorb in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) of the third embodiment are: The benzyl ketal compound of the radical radiation curable coating composition of step a) which is 2,2-diethoxyacetophenone (CAS 6175-45-7), and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: iii-6'') an oxime ester compound which is 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8); iii-7'') A titanocene compound, which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3). iii-8'') a thioxanthone compound which is 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1); and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8), and iii-11'') Mixtures thereof.

[0104] According to a fourth embodiment, the one or more photoreactive compounds not absorbing in the range of about 375 nm to about 470 nm of the radical radiation curable coating composition of step a) are benzoin ether compounds, preferably 2-methoxy-1,2-diphenyl-ethanone (CAS 3524-62-7); 2-ethoxy-1,2-diphenyl-ethanone (CAS 574-09-4); 2-propoxy-1,2-diphenyl-ethanone (CAS 6652-27-3); 2-(1-methylethoxy)-1,2-diphenyl-ethanone (CAS 6652-28-4); 1,2-diphenyl-2-(1-propen-1-yloxy)-ethanone (CAS 51891-92-0); 2-methoxy-1,2-diphenyl-1-propanone (CAS 26592-16-5); 2-ethoxy-1,2-diphenyl-1-propanone (CAS 27962-49-8); 2-(1-methylpropoxy)-1,2-diphenyl-1-propanone (CAS 27962-50-1); 2-(1-methylethoxy)-1,2-diphenyl-1-propanone (CAS 65177-73-3); 2-(ethenyloxy)-1,2-diphenyl-1-propanone (CAS 93831-39-1); 2-(allyloxy)-2-phenyl-propiophenone (CAS 27962-52-3); and mixtures thereof.

[0105] According to said fourth embodiment, the one or more compounds absorbing in the range of about 375 nm to about 470 nm of the top curable coating composition of step b) are selected from the group consisting of acylphosphine oxide compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, alpha-amino-ketone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more benzophenone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, glyoxylate compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, benzyl ketal compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more benzophenone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more benzophenone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more benzophenone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of ... oxime ester compounds such as those described herein for the composition, titanocene compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more thioxanthone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more coumarin compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment, a mixture of one or more camphorquinone compounds such as those described herein for the top curable coating composition of step b) of the first embodiment and one or more amine compounds such as those described herein for the top curable coating composition of step b) of the first embodiment;and mixtures thereof.

[0106]

[0105] The method described herein includes a step c) partially simultaneously or after the step b) described herein, of at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) under said one or more indicia (x30) with a light-emitting diode (LED) curing unit (x50). On the other hand, in contrast to medium pressure mercury lamps with emission bands in the UV-A, UV-B and UV-C regions of the electromagnetic spectrum, UV-LED lamps emit radiation in the UV-A and / or visible (Vis) regions, for example in the range of about 375 nm to about 470 nm. Moreover, current UV-LED and Vis-LED lamps emit quasi-monochromatic radiation, i.e., they only emit at one wavelength, for example, 385 nm, 395 nm, 405 nm or 450 nm. Step c) of at least partially curing the one or more indicia (x30) is carried out by exposure to UV light at a LED curing unit (x50), preferably at 385 nm and / or 395 nm and / or 405 nm and / or 450 nm, emitted from a LED curing unit (x50). "Partially simultaneously" means that both steps are carried out partially simultaneously, i.e. the time of carrying out each step partially overlaps. In the context described herein, it must be understood that if the curing is carried out partially simultaneously with the application step b), the curing is effective after the formation of the one or more indicia (x30) before full or partial curing. Step c) should be carried out after step b) described herein, the time between said two steps being preferably less than 10 seconds, more preferably less than 5 seconds.

[0107]

[0106] The method described herein comprises, after step c) described herein, a step d) of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device described herein in order to orient at least a portion of the non-spherical magnetic or magnetizable pigment particles. Said step d) of exposing the coating layer (x10) to the magnetic field of a magnetic field generating device is preferably carried out i) for uniaxial orientation of the platelet-shaped magnetic or magnetizable pigment particles, ii) for biaxial orientation of the platelet-shaped magnetic or magnetizable pigment particles, iii) for simultaneous or partially simultaneous orientation of the platelet-shaped magnetic or magnetizable pigment particles in uniaxial and biaxial directions or iv) for biaxial and subsequently uniaxial orientation of the platelet-shaped magnetic or magnetizable pigment particles. According to one embodiment, step d) is carried out for uniaxial orientation of at least a portion of the magnetic or magnetizable pigment particles described herein. According to another embodiment, step d) is performed in order to biaxially orient at least a portion of the platelet-shaped magnetic or magnetizable pigment particles, preferably in order to biaxially orient at least a portion of the platelet-shaped magnetic or magnetizable pigment particles to have both X-axis and Y-axis substantially parallel to the substrate surface. For embodiments in which the method described herein comprises a step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device described herein in order to biaxially orient at least a portion of the magnetic or magnetizable pigment particles, the coating layer (x10) may be subsequently exposed to said magnetic field generating device two or more times. According to another embodiment, step d) consists of simultaneously or partially simultaneously orienting the pigment particles uniaxially and biaxially. According to another embodiment, step d) consists of two or more steps, a first step being performed in order to biaxially orient at least a portion of the platelet-shaped magnetic or magnetizable pigment particles and a second step being performed in order to uniaxially orient at least a portion of said particles.

[0108]

[0107] For the embodiment of the method described herein, in which the step of exposing the coating layer (x10) to the magnetic field of a magnetic field generating device described herein is performed to orient at least a portion of the magnetic or magnetizable pigment particles in a biaxial direction, it is required that at least a portion of the non-spherical magnetic or magnetizable pigment particles described herein consist of platelet-shaped magnetic or magnetizable pigment particles having an X-axis and a Y-axis defining the main extension plane of the particle. In contrast to needle-shaped pigment particles, which can be considered as one-dimensional particles, platelet-shaped pigment particles have an X-axis and a Y-axis defining the main extension plane of the particle. In other words, platelet-shaped pigment particles may be considered as two-dimensional particles due to the large aspect ratio of their dimensions, as can be seen from Figure 2. As shown in Figure 2, platelet-shaped pigment particles can be considered as two-dimensional structures with dimensions X and Y substantially larger than dimension Z. Platelet-shaped pigment particles are also referred to in the art as ellipsoidal particles or flakes. Such pigment particles may be described with a major axis X, corresponding to the longest dimension across the pigment particle, and a second axis Y, perpendicular to X, that also lies within said pigment particle.

[0109]

[0108] In contrast to uniaxial orientation, where the magnetic or magnetisable pigment particles are oriented such that only their major axis is restrained by the magnetic field, performing biaxial orientation means that the platelet-shaped magnetic or magnetisable pigment particles are oriented such that their two main axes are restrained. That is, each platelet-shaped magnetic or magnetisable pigment particle can be considered to have a major axis in the plane of the pigment particle and an orthogonal minor axis in the plane of the pigment particle. The major and minor axes of the platelet-shaped magnetic or magnetisable pigment particles are each oriented according to the magnetic field. Effectively, this results in platelet-shaped magnetic pigment particles being adjacent to each other substantially parallel to each other with gaps therebetween. In other words, biaxial orientation aligns the faces of the platelet-shaped magnetic or magnetisable pigment particles such that the faces of said pigment particles are oriented substantially parallel to the faces of the adjacent (in all directions) platelet-shaped magnetic or magnetisable pigment particles. The magnetic field generating devices and methods described herein allow for biaxial orientation of the platelet-shaped magnetic or magnetisable pigment particles described herein, such that they form sheet-like structures with their X and Y axes preferably substantially parallel to the substrate (x20) surface and are flattened in said two dimensions.

[0110]

[0109] Suitable magnetic field generating devices for uniaxially orienting the magnetic or magnetizable pigment particles described herein include, but are not limited to, dipole magnets, quadrupole magnets, and combinations thereof. The following devices are provided herein as illustrative examples:

[0111]

[0110] The optical effect known as the flip-flop effect (also referred to in the art as the switch effect) comprises a first printed portion and a second printed portion separated by a transition, where the pigment particles are aligned parallel to a first surface in the first portion and the pigment particles are aligned parallel to a second surface in the second portion. Methods and magnets for producing said effect are disclosed, for example, in US Patent Application Publication No. 2005 / 0106367 and EP Patent No. 1819525.

[0112]

[0111] An optical effect known as the rolling bar effect as disclosed in US Patent Application Publication No. 2005 / 0106367 may also be produced. The "rolling bar" effect is based on pigment particle orientation that mimics a curved surface across the coating. The observer sees a specular reflection zone that faces away from or towards the observer when the image is tilted. The pigment particles are aligned in a curved manner and follow a convex curve (also referred to in the art as negative curve orientation) or a concave curve (also referred to in the art as positive curve orientation). Methods and magnets that produce said effect are disclosed, for example, in EP 2263806, EP 1674282, EP 2263807, WO 2004 / 007095, WO 2012 / 104098, and WO 2014 / 198905.

[0113]

[0112] An optical effect known as the Venetian blind effect may also be produced. The Venetian blind effect involves pigment particles oriented to impart visibility to the underlying substrate surface along a particular direction of observation such that indicia or other features present on or in the substrate surface are apparent to the observer while they obstruct visibility along other directions of observation. Methods and magnets for producing said effect are disclosed, for example, in U.S. Pat. No. 8,025,952 and European Patent No. 1,819,525.

[0114]

[0113] An optical effect known as the moving rings effect may also be produced. The moving rings effect consists of optical illusion images of objects such as funnels, cones, bowls, circles, ellipses, and hemispheres that appear to move in any xy direction depending on the tilt angle of the optical effect layer. Methods and magnets for producing said effect are disclosed, for example, in EP 1710756, US 8,343,615, EP 2306222, EP 2325677, WO 2011 / 092502, US 2013 / 0084411, WO 2014108404, and WO 2014 / 108303.

[0115]

[0114] An optical effect may also be produced which produces the optical impression of a pattern of light and dark areas that moves upon tilting of the effect. Methods and magnets for producing said effect are disclosed, for example, in WO 2013 / 167425.

[0116]

[0115] Optical effects may also be produced that produce the optical impression of a loop-shaped body with a size that changes upon the slope of the effect. Methods and magnets for producing these optical effects are disclosed, for example, in WO 2017 / 064052, WO 2017 / 080698 and WO 2017 / 148789.

[0117]

[0116] The optical impression of one or more loop-shaped bodies that change shape when tilting the optical effect layer may also be produced. Methods and magnets for producing said effect are disclosed, for example, in WO 2018 / 054819.

[0118]

[0117] An optical effect may also be produced that gives the optical impression of a moving and rotating lunar crescent when tilted. Methods and magnets for producing said effect are disclosed, for example, in WO 2019 / 215148.

[0119]

[0118] An optical effect may be produced that produces the optical impression of a loop-shaped body that changes size and shape when tilted. Methods and magnets for producing said effect are disclosed, for example, in WO 2020 / 052862.

[0120]

[0119] The optical effect producing the optical impression of an ortho-parallax effect may be produced, namely in this case in the form of a bright reflective vertical bar which moves longitudinally when the substrate is tilted about the horizontal / latitudinal axis, or horizontally / latitudinal when the substrate is tilted about the longitudinal axis. Methods and magnets for producing said effect are disclosed, for example, in WO 2020 / 160993.

[0121]

[0120] An optical effect may be produced that produces the optical impression of a loop-shaped body surrounded by one or more loop-shaped bodies, said one or more loop-shaped bodies having their shape and / or their brightness that change on tilt. Methods and magnets for producing said effect are disclosed, for example, in WO 2020 / 193009.

[0122]

[0121] Optical effects may be produced that result in the optical impression of multiple dark spots and multiple bright spots that move and / or appear and / or disappear diagonally when the substrate is tilted, as well as moving and / or appearing and / or disappearing diagonally when the substrate is tilted. Methods and magnets for producing said effects are disclosed, for example, in WO 2021 / 083809 and WO 2021 / 083808.

[0123]

[0122] The magnetic field generating devices described herein may be at least partially embedded in a non-magnetic supporting matrix made of one or more non-magnetic materials.

[0124]

[0123] The non-magnetic materials of the non-magnetic support plate (x40) described herein and the non-magnetic support matrix described herein are preferably independently selected from the group consisting of non-magnetic metals and engineering plastics and polymers, including but not limited to aluminum, aluminum alloys, brass (an alloy of copper and zinc), titanium, titanium alloys, and austenitic steel (i.e., non-magnetic steel). Engineering plastics and polymers include, but are not limited to, polyaryletherketone (PAEK) and its derivatives, polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyetheretherketoneketone (PEEKK), and polyetherketoneetherketoneketone (PEKEKK); polyacetal, polyamide, polyester, polyether, copolyetherester, polyimide, polyetherimide, high density polyethylene (HDPE), ultra-high molecular weight polyethylene (UHMWPE), polybutylene terephthalate (PBT), polypropylene, acrylonitrile butadiene styrene (ABS) copolymers, fluorinated and perfluorinated polyethylene, polystyrene, polycarbonate, polyphenylene sulfide (PPS), and liquid crystal polymers. Preferred materials are PEEK (polyetheretherketone), POM (polyoxymethylene), PTFE (polytetrafluoroethylene), Nylon (polyamide), and PPS.

[0125]

[0124] The magnetic field generating device described herein may comprise a magnetic plate carrying one or more reliefs, impressions or incisions. WO 2005 / 002866 and WO 2008 / 046702 are examples of such impressed magnetic plates.

[0126]

[0125] The magnetic field generating device described in this specification may be a soft magnetic plate supporting one or more indicia in the form of recesses and / or protrusions, or a soft magnetic plate containing one or more spaces having the shape of one or more indicia, and the orientation step is carried out by forming an assembly of a substrate (x20) supporting a coating layer (x10) on a soft magnetic plate, and said assembly is moved by the inhomogeneous magnetic field of a static magnetic field generating device (x40) in order to orient at least a portion of the platelet-shaped magnetic or magnetizable pigment particles in two axial directions, as described in WO 2018 / 019594 and WO 2018 / 033512.

[0127]

[0126] The magnetic field generating device described in this specification may be a magnetic assembly (x30) including a soft magnetic plate including one or more spaces for accommodating one or more dipole magnets and including one or more recesses and / or one or more protrusions forming one or more continuous loop-shaped indicia and / or one or more discontinuous loop-shaped indicia, as described in WO 2020 / 025218, or a magnetic assembly including a soft magnetic plate including one or more spaces and one or more dipole magnets arranged in the one or more spaces, facing one or more spaces and / or one or more spaces arranged below the soft magnetic plate and one or more pairs of two dipole magnets arranged at a regular interval, as described in WO 2020 / 025482.

[0128]

[0127] There is no limitation on the magnetic field generating devices suitable for biaxially orienting the platelet-shaped magnetic or magnetizable pigment particles described herein.

[0129]

[0128] A particularly preferred apparatus for orienting pigment particles in two axes is disclosed in EP-A-2 157 141. Upon movement of a substrate supporting a coating layer comprising pigment particles, the apparatus disclosed in EP-A-2 157 141 provides a dynamic magnetic field which causes the pigment particles to change direction and rapidly oscillate until both of their main axes (X-axis and Y-axis) are substantially parallel to the substrate surface, i.e. the pigment particles rotate and flatten in said two dimensions into a stable sheet-like formation with their X- and Y-axes substantially parallel to the substrate surface.

[0130]

[0129] Other particularly preferred devices for orienting pigment particles in two axes include linear permanent magnet Halbach arrays, i.e. devices comprising a plurality of magnets with different magnetization directions and a cylinder arrangement. A detailed description of Halbach permanent magnets is given by ZQZhu and D.Howe (Halbach permanent magnet machines and applications: a review, IEE.Proc.Electric Power Appl, 2001, 148, pp. 299-308). The magnetic field provided by such a Halbach array has the property that it is concentrated on one side while it is weakened to almost zero on the other side. Linear Halbach arrays are disclosed, for example, in WO 2015 / 086257 and WO 2018 / 019594, and Halbach cylinder arrangements are disclosed in EP 3224055.

[0131]

[0130] Another particularly preferred device for orienting pigment particles in two directions is a rotating magnet, said magnet comprising a disk-shaped rotating magnet or magnetic field generator that is substantially magnetized along their diameter. Suitable rotating magnets or magnetic field generators are described in US Patent Application Publication No. 2007 / 0172261, said rotating magnets or magnetic field generators generating a radially symmetric time-varying magnetic field allowing for a dual orientation of the magnetic or magnetizable pigment particles of the uncured coating composition. These magnets or magnetic field generators are driven by a shaft (or spindle) connected to an external motor. Chinese Patent No. 102529326 discloses examples of devices comprising a rotating magnet that may be suitable for orienting magnetic or magnetizable pigment particles in two directions. In a preferred embodiment, the device suitable for orienting magnetic or magnetizable pigment particles in two directions is a shaftless disk-shaped rotating magnet or magnetic field generator restrained in a housing made of a non-magnetic, preferably non-conductive material, driven by one or more coils of magnet wire wound around the housing. Examples of such shaft-free, disk-shaped rotating magnets or magnetic field generators are disclosed in WO 2015 / 082344, WO 2016 / 026896, and WO 2018 / 141547.

[0132]

[0131] Another particularly preferred apparatus for orienting pigment particles in biaxial directions comprises: a) at least a first set (S1) and a second set (S2), each of the first and second sets (S1, S2) including a first bar dipole magnet having a magnetic axis oriented substantially parallel to the substrate during magnetization orientation, and two bar dipole magnets having magnetic axes oriented substantially perpendicular to the substrate; and b) a third pair of bar dipole magnets (P1) having magnetic axes oriented substantially parallel to the substrate, such as those disclosed in WO 2021 / 239607.

[0133]

[0132] During the magnetic orientation step described herein of the non-spherical magnetic or magnetizable pigment particles, the substrate (x20) supporting the coating layer (x10) may be placed on a non-magnetic support plate (x40) made of one or more non-magnetic materials.

[0134]

[0133] During the magnetic orientation step of the magnetic or magnetizable pigment particles described herein, the position of the magnetic field generating device is not limited and depends on the selection and design of the magnetic orientation pattern to be produced. Depending on the selection and design of the magnetic orientation pattern to be produced, the magnetic field generating device may be placed under the substrate (x20) or above the coating layer (x10).

[0135]

[0134] The method described herein comprises, partially simultaneously with or after step d) described herein, a step e) of at least partially curing the coating layer (x10) in curing units (x60) emitting at least between 250 nm and 320 nm.

[0136]

[0135] The method described herein comprises a step e) of at least partially curing the coating layer (x10) in a curing unit (x60) radiating at least between 250 nm and 320 nm, partially simultaneously or after step d) described herein. By "partially simultaneously" it is meant that both steps are performed partially simultaneously, i.e. the times of performing each step partially overlap. In the context described herein, it must be understood that if the curing is performed partially simultaneously with the application step c), the curing takes effect after the orientation of the non-spherical magnetic or magnetisable pigment particles in the coating layer (x10) before full or partial curing.

[0137]

[0136] According to one embodiment, for example as shown in FIG. 1, the method described herein comprises the following steps: a) applying onto the surface of a substrate (x20) a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles as described herein; After step a), a step b) of applying a top coating composition in the form of one or more indicia (x30) onto the coating layer (x10) as described herein, partially simultaneously with or subsequent to step b), step c) of at least partially curing one or more indicia (x30) and one or more areas of the coating layer (x10) beneath said one or more indicia (x30) with an LED curing unit (x50) as described herein; after step c), step d) of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device (B1) in order to orient at least a portion of the magnetic or magnetisable pigment particles as described herein in areas of the coating layer (x10) not under said one or more indicia (x30), said step d) may be carried out to orient at least a portion of the magnetic or magnetisable pigment particles as described herein uniaxially (Figure 1), biaxially (not shown in Figure 1), biaxially and then uniaxially (two steps, not shown in Figure 1) or biaxially and uniaxially partially simultaneously or simultaneously (one step, not shown in Figure 1); Partially simultaneously with or after step d), step e) of at least partially curing the coating layers (x10) with curing units (x60) emitting at least between 250 nm and 320 nm as described herein.

[0138] According to one embodiment, the method described herein further comprises the step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles, said step being carried out subsequent to or partially simultaneously with step b) and prior to step c), i.e. the method described herein may comprise the following steps: a) applying a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles as described herein onto a surface of a substrate (x20); After step a), a step b) of applying a top coating composition in the form of one or more indicia (x30) onto the coating layer (x10) described herein, After step b) or partially simultaneously, exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles described herein, said step may be carried out to orient at least a portion of the magnetic or magnetisable pigment particles described herein uniaxially (one step), to orient biaxially (one step), to orient biaxially and then uniaxially (two steps), or to orient biaxially and uniaxially partially simultaneously or simultaneously (one step), After step b) and the orienting step with the magnetic field generating device, a step c) of at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) below said one or more indicia (x30) with a LED curing unit (x50) as described herein, after step c), step d) of exposing the coating layer (x10) to a magnetic field of a second magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles described herein in areas of the coating layer (x10) not under said one or more indicia (x30), said step d) may be carried out to orient at least a portion of the magnetic or magnetizable pigment particles described herein uniaxially (one step), to orient biaxially (one step), to orient biaxially and then uniaxially (two steps), or to orient biaxially and uniaxially partially simultaneously or simultaneously (one step); Partially simultaneously with or after step d), step e) of at least partially curing the coating layers (x10) with curing units (x60) emitting at least between 250 nm and 320 nm as described herein.

[0139]

[0138] According to another embodiment, the method described herein further comprises a step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles, said step may be performed after step a) and before step b).

[0140] According to one embodiment, the method described herein comprises the steps of: a) applying onto a substrate (x20) a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles as described herein; Following step a), a step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles described herein, said step may be carried out to uniaxially orient (1 step), to biaxially orient (1 step), to biaxially and then uniaxially orient (2 steps) or to biaxially and uniaxially partially simultaneously or simultaneously orient (1 step) at least a portion of the magnetic or magnetisable pigment particles described herein, b) partially simultaneously with or subsequent to the orientation step with the magnetic field generating device, applying a top coating composition in the form of one or more indicia (x30) onto the coating layer (x10) as described herein, partially simultaneously with or subsequent to step b), a step c) of at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) beneath said one or more indicia (x30) with an LED curing unit (x50) as described herein; step c) is followed by a step d) of exposing the coating layer (x10) to the magnetic field of a second magnetic field generator, of a third magnetic field generator, or of a second and a third magnetic field generator, in order to orient at least a portion of the magnetic or magnetizable pigment particles as described herein, said step d) being optionally carried out in areas of the coating layer (x10) not under said one or more indicia (x30) for uniaxial orientation (1 step), for biaxial orientation (1 step), for biaxial and then uniaxial orientation (2 steps) or for biaxial and uniaxial orientation partially simultaneously or simultaneously (1 step); and Partially simultaneously with or subsequent to step d), it comprises a step e) of at least partially curing the coating layers (x10) with curing units (x60) emitting at least between 250 nm and 320 nm as described herein.

[0141] According to another embodiment, the method described herein comprises the steps of: a) applying onto the surface of a substrate (x20) a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles as described herein; Following step a), a step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles described herein, said step may be carried out to uniaxially orient (1 step), to biaxially orient (1 step), to biaxially and then uniaxially orient (2 steps) or to biaxially and uniaxially partially simultaneously or simultaneously orient (1 step) at least a portion of the magnetic or magnetisable pigment particles described herein, b) partially simultaneously with or subsequent to the orientation step with the magnetic field generating device, applying a top coating composition in the form of one or more indicia (x30) onto the coating layer (x10) as described herein; Following step b), a step of exposing the coating layer (x10) to the magnetic field of a second magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles described herein, said step may be carried out to uniaxially orient (1 step), to biaxially orient (1 step), to biaxially and then uniaxially orient (2 steps) or to biaxially and uniaxially partially simultaneously or simultaneously orient (1 step) at least a portion of the magnetic or magnetisable pigment particles described herein; c) partially simultaneously with or subsequent to the step of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device, at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) below said one or more indicia (x30) with an LED curing unit (x50) as described herein; Step c) is followed by a step d) of exposing the coating layer (x10) to a magnetic field of a third magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles described herein in areas of the coating layer (x10) not under said one or more indicia (x30), said step d) may be carried out to uniaxially orient (1 step), to biaxially orient (1 step), to biaxially and then uniaxially orient (2 steps) or to biaxially and uniaxially partially simultaneously or simultaneously orient (1 step) at least a portion of the magnetic or magnetizable pigment particles described herein; and Partially simultaneously with or subsequent to step d), it may comprise a step e) of at least partially curing the coating layers (x10) with curing units (x60) emitting at least between 250 nm and 320 nm as described herein.

[0142] The three following steps: a) of applying a radical radiation curable coating composition comprising non-spherical magnetic or magnetisable pigment particles as described herein on a surface of a substrate (x20); after step a), b) of applying a top coating composition in the form of one or more indicia (x30) on a coating layer (x10) as described herein; and partly simultaneously with or after step b), step c) of at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) below said one or more indicia (x30) with an LED curing unit (x50) as described herein may be carried out more than once, and the method comprising two or more steps a) to c) as described herein may further comprise, after the last step c), applying a top coating composition in the form of one or more indicia (x30) on a coating layer (x10) as described herein. further comprising step d) of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device to orient at least a portion of the magnetic or magnetizable pigment particles as described herein in areas of the coating layer (x10) not under the plurality of indicia (x30), said step d) may be performed to uniaxially orient at least a portion of the magnetic or magnetizable pigment particles as described herein, to orient biaxially, to orient biaxially and then uniaxially, or to orient biaxially and uniaxially partially simultaneously or simultaneously; and further comprising step e) of at least partially curing the coating layer (x10) in a curing unit (x60) radiating at least between 250 nm and 320 nm as described herein, partially simultaneously with or after step d).

[0143] Alternatively, steps a) and b) may be interchanged, i.e. the method described herein comprises the following steps: applying a top coating composition onto a substrate surface in the form of one or more indicia as described herein; applying a radical radiation curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles described herein onto the one or more indicia; exposing the coating layer to a magnetic field of a magnetic field generating device to orient at least a portion of the magnetic or magnetisable pigment particles described herein, said step may be carried out to uniaxially orient, to biaxially orient, to biaxially and then uniaxially or partially simultaneously or simultaneously orient at least a portion of the magnetic or magnetisable pigment particles described herein; at least partially curing the one or more indicia and one or more areas of the coating layer (x10) on said one or more indicia (x30) with an LED curing unit (x50) as described herein, either simultaneously with or after the orienting step; thereafter, exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles as described herein in areas of the coating layer (x10) that are not on said one or more indicia (x30), said steps may be carried out to orient at least a portion of the magnetic or magnetizable pigment particles as described herein uniaxially, to orient biaxially, or to orient biaxially and then uniaxially, or to orient biaxially and uniaxially partially simultaneously, or simultaneously; and Partially simultaneously with or after the orientation step, at least partially curing the coating layers (x10) with curing units (x60) emitting at least between 250 nm and 320 nm as described herein.

[0144]

[0143] Alternatively, the step of at least partially curing the coating layer (x10) with a curing unit (x60) emitting at least between 250 nm and 320 nm as described herein may be replaced with a step of at least partially curing the coating layer (x10) with a LED curing unit (x50) as described herein, provided that the second step of applying a top coating composition as described herein to the entire surface of the coating layer (x10) is performed after the step of at least partially curing the one or more indicia (x30) and one or more areas of the coating layer (x10) below said one or more indicia (x30) with a LED curing unit (x50). For example, the method as described herein comprises the following steps: applying a radical radiation curable coating composition comprising the non-spherical magnetic or magnetisable pigment particles described herein onto a substrate surface; after said step, exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles as described herein, said step may be carried out to uniaxially orient, to biaxially orient, to biaxially and then uniaxially or to partially simultaneously or simultaneously or preferably to biaxially orient, at least a portion of the magnetic or magnetisable pigment particles as described herein, applying, partially simultaneously with or after the orienting step with the magnetic field generating device, a top coating composition as described herein in the form of one or more indicia (x30) onto a coating layer (x10) as described herein; after said step, exposing the coating layer (x10) to the magnetic field of a second magnetic field generating device in order to orient at least a portion of the magnetic or magnetisable pigment particles as described herein, said step may be carried out in order to orient at least a portion of the magnetic or magnetisable pigment particles as described herein uniaxially, in order to orient biaxially and then uniaxially, or in order to orient biaxially and uniaxially partially simultaneously or simultaneously, preferably in order to orient uniaxially; partially simultaneously with or after exposing the coating layers (x10) to the magnetic field of the second magnetic field generating device, at least partially curing the top coating composition and the lower coating layers (x10) with an LED curing unit (x50) as described herein; After the above step, applying a top coating composition as described herein onto the entire surface of the coating layer (x10) as described herein; after said step, exposing the coating layer (x10) to a magnetic field of a third magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles described herein, said step may be carried out in order to orient at least a portion of the magnetic or magnetizable pigment particles described herein uniaxially, biaxially, or partially simultaneously or simultaneously biaxially and uniaxially, preferably uniaxially; and Simultaneously with or subsequent to the above step, at least partially curing the top coating composition and coating layers (x10) with LED curing units (x50) as described herein.

[0145]

[0144] The present invention provides a method as described herein for making a substrate (x20) comprising an optical effect layer (OEL) exhibiting one or more indicia (x30) on a substrate (x20) as described herein and the resulting one or more optical effect layers (OEL). The substrate (x20) as described herein is preferably selected from the group consisting of paper or other fibrous materials (including woven and nonwoven fibrous materials) such as cellulose, paper-containing materials, glass, metal, ceramic, plastics and polymers, metallized plastics or polymers, composite materials, and mixtures or combinations of two or more thereof. Typical paper, paper-like or other fibrous materials are composed of various fibers including, but not limited to, abaca, cotton, linen, wood pulp, and mixtures thereof. As is well known to those skilled in the art, cotton and cotton / linen mixtures are preferred for banknotes, while wood pulp is commonly used in non-banknote security documents. According to other embodiments, the substrate (x20) described herein is based on plastics and polymers, metallized plastics or polymers, composite materials, and mixtures or combinations of two or more thereof. Suitable examples of plastics and polymers include polyolefins such as polypropylene (PP), including polyethylene (PE) and biaxially oriented polypropylene (BOPP), polyamides, polyesters such as poly(ethylene terephthalate) (PET), poly(1,4-butylene terephthalate) (PBT), poly(ethylene 2,6-naphthoate) (PEN), and polyvinyl chloride (PVC). Spunbond olefin fibers, such as those sold under the trademark Tyvek®, may also be used as substrates. Representative examples of plated plastics or polymers include the above plastics or polymeric materials with metals disposed on the surface in a continuous or discontinuous manner. Representative examples of metals include, but are not limited to, aluminum (Al), chromium (Cr), copper (Cu), gold (Au), silver (Ag), alloys thereof, and combinations of two or more of the aforementioned metals. The metallization of the plastic or polymeric material may be carried out by an electrodeposition process, a high vacuum coating process, or a sputtering process.Representative examples of composite materials include, but are not limited to, multi-layered structures or laminates of paper and at least one plastic or polymeric material such as those mentioned above, as well as plastic and / or polymeric fibers incorporated into paper-like or fibrous materials such as those mentioned above. Of course, the substrate may contain further additives known to those skilled in the art, such as fillers, sizing agents, whitening agents, processing aids, reinforcing agents, or wet strength agents. When the OELs exhibiting one or more indicia (x30) made according to the present invention are used for decorative or cosmetic purposes, including, for example, nail lacquers, said OELs may be made on other types of substrates, including animal or human nails, artificial nails, or other parts.

[0146]

[0145] Also described herein is a method for producing a security document, or a decorative element or body, the method comprising: a) preparing a security document, or a decorative element or body, and b) preparing one or more optical effect layers as described herein, in particular those obtained by the methods described herein, for inclusion in the security document, or the decorative element or body.

[0147]

[0146] Once the OEL made according to the present invention is on a security document or article, the substrate may include printing, coating, or laser mark or laser perforation indicia, water gauge, anti-counterfeit thread, fiber, planchette, luminescent compound, window, foil, decal, and combination of two or more thereof, for the purpose of further improving the security level and resistance of said security document or article to counterfeiting and illegal duplication. For the same purpose of further improving the security level and resistance of security documents and articles to counterfeiting and illegal duplication, the substrate may include one or more marking substances or identification additives and / or machine readable substances (e.g. luminescent substances, UV / visible / IR absorbing substances, magnetic substances, and combinations thereof).

[0148]

[0147] If necessary, a primer layer may be applied to the substrate before step a). This may enhance the quality or promote adhesion of the OELs described herein. Examples of such primer layers may be found in WO 2010 / 058026.

[0149]

[0148] In order to improve the durability against dirt or chemical resistance and cleanliness, and thus the circulation life, of the security document, article, or decorative element or object comprising the OEL obtained by the method described herein, or in order to modify their aesthetics (e.g. optical gloss), one or more protective layers may be applied on the OEL. If present, the one or more protective layers typically consist of a protective varnish. The protective varnish may be a radiation curable composition, a thermal drying composition, or any combination thereof. Preferably, the one or more protective layers are a radiation curable composition, more preferably a UV-Vis curable composition. The protective layer is typically applied after the formation of the OEL.

[0150]

[0149] The present invention further provides an optical effect layer (OEL) exhibiting one or more indicia (x30) as described herein and produced by the method as described herein. The shape of the optical effect layer (OEL) as described herein may be continuous or discontinuous. According to one embodiment, the shape of the coating layer (x10) represents one or more indicia, dots and / or lines, said indicia having the same shape or different shapes as one or more indicia (x30) consisting of the top coating composition as described herein.

[0151]

[0150] The OEL exhibiting one or more indicia (x30) described herein may be applied directly onto a substrate on which it will remain permanently (such as for banknote applications). Alternatively, the optical effect layer may also be applied onto a temporary substrate for fabrication purposes from which the OEL is subsequently removed. This may facilitate, for example, the fabrication of the optical effect layer (OEL), especially while the binder material is still in its fluid state. The temporary substrate may then be removed from the OEL after curing the coating composition for fabrication of the OEL.

[0152] Alternatively, in other embodiments, the adhesive layer may be present on one or more indicating indicia (x30) or on the side of the substrate comprising the OEL, said adhesive layer being on the substrate opposite the side on which the OEL is provided or on the same side as the OEL and on the OEL. Thus, the adhesive layer may be applied to the OEL or to the substrate, said adhesive layer being applied after the curing step is finished. Such articles may be attached to various kinds of documents or other articles or goods without machinery and printing and other processes involving fairly high effects. Alternatively, the substrates described herein comprising the OELs described herein may be in the form of transfer foils, which can be applied to the document or article in a separate transfer step. For this purpose, the substrate is provided with a release coating on which the OEL is produced as described herein. One or more adhesive layers may be applied to the optical effect layer so produced.

[0153]

[0152] Also described herein are substrates comprising more than one, ie, two, three, four, etc., optical effect layers (OELs) obtained by the methods described herein.

[0154] Also described herein are articles, documents, in particular security documents, decorative elements, and decorative objects, comprising an optical effect layer (OEL) made according to the invention. The articles, in particular security documents, decorative elements, or decorative objects, may comprise more than one (e.g., two, three, etc.) OEL made according to the invention.

[0155]

[0154] As mentioned above, OELs made according to the present invention may be used for decorative purposes and to protect and authenticate security documents.

[0156]

[0155] Representative examples of decorative elements or objects include, but are not limited to, articles of luxury goods, cosmetic packaging, automobile parts, electronic / electrical appliances, furniture, and nails.

[0157]

[0156] Security documents include, but are not limited to, value documents and value items. Representative examples of value documents include, but are not limited to, banknotes, certificates, tickets, invoices, certificates, revenue stamps, and tax labels, agreements, etc., passports, identity cards, visas, driver's licenses, bank cards, credit cards, transaction cards, access documents or cards, admission tickets, public transport tickets, academic diplomas or entitlements, etc., preferably identity documents such as banknotes, identity documents, entitlement documents, driver's licenses, and credit cards. The term "value items" refers in particular to packaging materials for cosmetics, dietary supplements, medicines, alcohol, tobacco articles, beverages or food, electrical / electronic articles, textiles or jewelry, i.e., articles that are protected against counterfeiting and / or illegal duplication to ensure the contents of the package, such as for example, for genuine medicines. Examples of these packaging materials include, but are not limited to, labels, such as authentication brand labels, tamper-evident labels, and seals. It is pointed out that, without limiting the scope of the present invention, the disclosed substrates, value documents, and value items are given solely for illustrative purposes.

[0158]

[0157] Alternatively, the optical effect layers (OELs) described herein may be fabricated on a secondary substrate, such as, for example, a security thread, security stripe, foil, decal, window, or label, and then transferred to the security document in a separate step.

[0159]

[0158] Those skilled in the art may foresee some modifications from the specific embodiments described above without departing from the spirit of the present invention. Such modifications are encompassed by the present invention.

[0160]

[0159] Additionally, all documents referenced throughout the specification are incorporated by reference in their entirety, as if fully set forth herein. EXAMPLES

[0161]

[0160] The present invention will now be described in more detail with reference to the following non-limiting examples. The following examples provide more detail on the preparation of an optical effect layer (OEL) exhibiting one or more indicia in the form of a rectangle. A screen printing composition comprising magnetic pigment particles and a top coating inkjet printing composition was prepared and is described in Tables 1A1-A3. [Table 1] JPEG2025507666000003.jpg200149 JPEG2025507666000004.jpg206149 JPEG2025507666000005.jpg73149 [Table 2] JPEG2025507666000007.jpg200149 JPEG2025507666000008.jpg206149 JPEG2025507666000009.jpg175149 [Table 3] The following ingredients were used: EBECRYL® 2959: Epoxy acrylate oligomer (Allnex) [CAS 106797-53-9] TMPTA: Trimethylolpropane triacrylate (Allnex) [CAS 15625-89-5] TPGDA: Tripropylene glycol diacrylate (Allnex) [CAS 42978-66-5] HDDA: 1,6-Hexamethylene diacrylate (Allnex) [CAS 13048-33-4] GENORAD * 16: Polymerization inhibitor (Rahn) CAS free] AEROSIL® 200: [Fumed silica (Evonik) CAS free] BYK 371: Solution of acrylic functional polyester modified polydimethylsiloxane [(BYK) CAS free] TEGO® Foamex N: (Evonik) [CAS Free] Pigment 1: Magnetic pigment particles (VIAVI Solutions, Santa Rosa, CA [no CAS]) with a diameter of approximately 10.7 μm 50 and seven-layered patina platelet-shaped optically variable magnetic pigment particles having a flake shape with a thickness of about 1 μm. Pigment 2: VIAVI Solutions (Santa Rosa, CA) [No CAS] Diameter d approx. 19 μm 50 and five-layered silver magnetic pigment particles having a flake shape with a thickness of about 1 μm. Omnirad 1173: 2-Hydroxy-2-methylpropiophenone (IGM Resins) [CAS 7473-98-5] Omnirad 2959: 2-Hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (IGM Resins) [CAS 106797-53-9] Omnirad 380: Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (IGM Resins) [CAS 162881-26-7] Omnirad TPO-L: 2,4,6-Trimethylbenzoyl-ethoxylphenylphosphine oxide (IGM Resins) [CAS 84434-11-7] Omnipol 910: α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (IGM Resins) [CAS 886463-10-1] GENOCURE *FMP: 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (Rahn) [CAS 2020359-04-8] Omnirad 4817: 2-Methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (IGM Resins) [CAS 71868-10-5] ESACURE 1001M: 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (IGM Resins) [CAS 272460-97-6] Omnipol ASA: Poly(ethylene glycol) bis(p-dimethylaminobenzoate) (IGM Resins) [CAS 71512-90-8] Omnirad EMK: 4,4'-Bis(diethylamino)benzophenone (IGM Resins) [CAS 90-93-7] Omnirad MBF: 2-Oxo-2-phenylacetic acid methyl ester (IGM Resins) (CAS 15206-55-0); Omnirad 754: 2-[2-Oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (IGM Resins) [CAS 211510-16-6] Omnirad BDK: 2,2-Dimethoxy-1,2-diphenylethan-1-one (IGM Resins) [CAS 24650-42-8] SpeedCure 8001: 4-Cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (Lambson) [CAS1206525-75-8] Omnirad 784: Bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (IGM Resins) [CAS 125051-32-3] Omnirad ITX: Isopropyl-9H-thioxanthen-9-one (IGM Resins) [CAS 5495-84-1] Omnirad BP: Diphenylmethanone (IGM Resins) [CAS 119-61-9] GENOCURE * MBB: 2-benzoylbenzoic acid methyl ester (Rahn) [CAS 606-28-0] ESACURE 3644:3-(4-C 10 -C 13 -benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (IGM Resins) [CAS 2243703-91-3] GENOCURE * CQ: Camphorquinone (Rahn) [CAS 10373-78-1] SpeedCure EAQ: 2-Ethyl-9,10-anthracenedione (Lambson) [CAS 84-51-5] ESACURE TZT: Blend of 2,4,6-trimethylbenzophenone & (4-methylphenyl)phenylmethanone (liquid eutectic) (IGM Resins) [CAS 954-16-5 & 134-84-9] Omnirad 4MBZ: (4-Methylphenyl)phenylmethanone (IGM) [CAS 134-84-9] SpeedCure XKm: Ethyl (3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate (Lambson) [CAS 1539267-56-5] SpeedCure BMS: 4-(4-methylphenylthio)benzophenone (Lambson) [CAS 83846-85-9] Omnirad 4PBZ: 4-Phenylbenzophenone (IGM Resins) [CAS 2128-93-0] Omnipol 2702: α-(1-benzoylbenzoyl)-ω-[(1-benzoylbenzoyl)oxy]-poly(oxy-1,2-ethanediyl) (IGM Resins) [CAS 1246194-73-9] Omnirad 991: 2-Ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate (IGM Resins) [CAS 75005-95-7] SpeedCure EAQ: 2-Ethyl-9,10-anthracenedione (Lambson) [CAS 84-51-5] GENOCURE * DEAP: 2,2-diethoxyacetophenone (Rahn) [CAS 6175-45-7]

[0162] (Preparation of Composition)

[0161] Screen printing compositions were prepared independently by mixing the ingredients shown in Tables 1A1-1A3 using a Dispermat CV-3 at 2000 rpm for 10 minutes.

[0163]

[0162] Inkjet top printing compositions were independently prepared by mixing the ingredients shown in Tables 1A1-1A3 using Dispermat LC220-12 at room temperature and 1000 rpm for 10 minutes.

[0164]

[0163] The viscosities of the compositions were measured independently at 25°C using a Brookfield viscometer (model "DV-I Prime", spindle S27 at 100 rpm for screen printing compositions and S00 at 50 rpm for top-coating inkjet printing compositions) and are shown in Tables 1A1-1A3.

[0165] (Preparation of Optical Effect Layer (OEL))

[0164] Optical effect layers (OELs) were prepared by the methods of the invention (E1 to E39) and the comparative methods (C1 to C6).

[0166] As shown in FIG. 1, the method included the following steps: Step a) (not shown) of screen printing a screen printing composition onto a substrate (120) to form a coating layer (110); After step a), step b) of inkjet printing a top coating inkjet printing composition to form indicia (130); After step b), a step c) of at least partially curing the indicia (130) and the area of ​​the coating layer (110) below said indicia (130) with an LED curing unit (150); After step c), a step d) of exposing the coating layer (110) to a magnetic field of a magnetic field generating device (B1) in order to uniaxially orient at least a portion of the magnetic or magnetisable pigment particles in the not yet cured areas of the coating layer (110), Partially simultaneously with step d), step e) of curing the coating layer (110) in a Hg curing unit (160) while maintaining a magnetic field generating device (B1) in the vicinity of the coating layer (110) to form an optical effect layer.

[0167] Comparative Examples C1-C6 were prepared according to the following method: screen printing the screen printing composition onto a substrate to form a coating layer; followed by inkjet printing a top coating inkjet printing composition to form indicia; followed by exposing the coating layer to an LED curing unit; subsequently exposing the coating layer to a magnetic field of a first magnetic field generating device in order to uniaxially orient at least a portion of the magnetic or magnetizable pigment particles in the as yet uncured areas of the coating layer; Partially simultaneously with the step of exposing the coating layer to the magnetic field of the first magnetic field generating device, exposing the coating layer to an Hg curing unit while maintaining the first magnetic field generating device in proximity to the coating layer.

[0168] (Screen Printing of Screen Printing Composition)

[0167] The screen printing compositions described in Tables 1A1-A3 were independently applied by hand screen printing using a T90 screen onto a substrate (Guardian® from CCL Secure, substrate, 75 micrometers thick, size: 70 mm x 70 mm) (x20) to form a coating layer (x10) having the following dimensions: 25 mm x 25 mm and a thickness of approximately 20 μm.

[0169] Inkjet Printing of Top Coating Inkjet Printing Composition

[0168] The top coating inkjet printing compositions described in 1A1-A3 were printed at approximately 5 g / m by DOD inkjet printing using a Konica Minolta KM1024i KM1024i printhead (360 dpi) to form indicia having a rectangular shape with the following dimensions: 20 mm x 12 mm. 2 were given separately.

[0170] Magnetic Orientation of Screen Printing Compositions

[0169] The step of exposing the coating layer (x10) to a magnetic field of a magnetic field generator described below was carried out separately to orient at least a portion of the magnetic or magnetizable pigment particles contained in the coating layer of the screen printing composition in a uniaxial direction, said magnetic field generator (B1) comprising a bar dipole magnet of length about 30 mm, width about 24 mm, and thickness about 6 mm, said bar dipole being embedded in a matrix made of POM and having the following dimensions: 40 mm x 40 mm x 15 mm. The north-south magnetic axis of the bar dipole magnet was parallel to the substrate (320) surface and parallel to the width. The bar dipole magnet was made of NdFeB N42.

[0171]

[0170] During magnetic orientation, the substrate (120) supporting the coating layer (110) was placed on the non-magnetic support plate made of POM as described above with the coating layer (110) facing the environment to form an assembly. The assembly was placed near and on top of the magnetic field generator such that the substrate (120) was at a distance of about 6 mm from the top surface of the rod-shaped dipole magnet.

[0172] (hardening unit) The following units were used in the preparation of the optical effect layer OEL: LED curing unit (150): UV-LED lamp from OmniCure® (Type AC4 50×25 mm 385 nm 8 W / cm) with an exposure time of about 0.5 seconds for all examples except E17′ and E36′ 2 ), where a UV-LED lamp (450 nm, 100 W) was used. Hg curing unit (x160): 2 lamps: iron-doped mercury lamp 200 W / cm2 from IST Metz GmbH + mercury lamp 200 W / cm 2 ; 2 passes at 100m / min

[0173]

[0172] After the curing step, each sample was rubbed with tissue paper to ensure curing of both the coating layer (110) and the indicia (130).

[0174] (Photos of Examples and Comparative Examples (FIGS. 3A-C))

[0173] Photographs of the optical effect layer (OEL) produced as described above are provided in Figure 3A for the first embodiment described herein, 3B for the second embodiment described herein, and 3C for the third embodiment described herein.

[0175]

[0174] As shown by the photographs of Fig. 3A (E1-E17), the optical effect layer OEL showing the indicia as well as the magnetic orientation of the particles in the magnetic field generating device, the particles, the dynamic movement of the rolling bar when tilting the substrate with bright and highly reflective areas, comprises: a) one or more alpha-hydroxy-ketone compounds, in particular 2-hydroxy-2-methylpropiophenone (CAS 7473-98-5, Omnirad 1173) and 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone (CAS 106797-53-9 (Omnirad 2959) in the screen printing composition and one or more alpha-hydroxyketones selected from the group consisting of the following compounds in the inkjet top printing composition: bi) one or more acylphosphine oxide compounds, in particular one or more compounds selected from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7, Omnirad 380) and 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7, Omnirad TPO-L); or b-ii) one or more α-amino-ketone compounds, in particular α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1, Omnipol 910); 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (CAS 2020359-04-8, GENOCURE * FMP) and 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one (CAS 71868-10-5, Omnirad 4817); or b-iii) one or more benzophenone compounds, in particular one or more compounds selected from the group consisting of 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6, Esacure 1001M) and 4,4'-bis(diethylamino)benzophenone (CAS 90-93-7, Omnirad EMK), and one or more amine compounds, in particular one or more compounds of poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA); or b-iv) one or more glyoxylate compounds, in particular one or more compounds selected from the group consisting of 2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0, Omnirad MBF) and 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate (CAS 211510-16-6, Omnirad 754); or one or more mixtures of glyoxylate compounds, in particular 2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0, Omnirad MBF) and one or more amine compounds, in particular poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA); or bv) one or more benzil diketal compounds, in particular 2,2-dimethoxy-1,2-diphenylethan-1-one (CAS 24650-42-8, Omnirad BDK); or b-vi) one or more oxime ester compounds, in particular 3-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione-2-(O-benzoyloxime) (CAS 1206525-75-8, SpeedCure 8001); or b-vii) one or more titanocene compounds, in particular bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3, Omnirad 784); or b-viii) one or more mixtures of thioxanthone compounds, in particular 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1, Omnirad ITX) and one or more amine compounds, in particular poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA); or b-ix) one or more coumarin compounds, in particular 3-(4-C 10 -C 13-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (CAS 2243703-91-3 (ESACURE 3644) and one or more amine compounds, in particular one or more mixtures of poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA); or bx) one or more camphorquinone compounds, in particular 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione (CAS 10373-78-1, GENOCURE * CQ) and one or more amine compounds, in particular poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA), according to the claimed method.

[0176]

[0175] Contrary to the examples according to the invention (E1-E17), comparative examples (C1-C2) made by the same process as claimed, except that the compounds in the screen printing composition and the compounds in the top coating inkjet printing composition did not consist of the first embodiment described herein, did not show the dynamic movement of the rolling bar when tilting the substrate due to the bright and highly reflective areas, combined with the indicia, magnetic orientation of the particles in the magnetic field generator. Comparative examples C1-C2 showed the dynamic movement of the rolling bar when tilting the substrate due to the magnetic orientation of the particles in the magnetic field generator, but did not show the indicia due to the absence of the specific compound or compounds absorbing in the range of about 375 nm to about 470 nm in the top curable coating composition.

[0177]

[0176] As shown by the photographs in Fig. 3B (E18 to E36), the optical effect layer OEL showing the indicia as well as the magnetic orientation of the particles in the magnetic field generator, the particles, the dynamic movement of the rolling bar when tilting the substrate with bright and highly reflective areas, is made of a) one or more benzophenone compounds, in particular diphenylmethanone (CAS 119-61-9, Omnirad BP); 2-benzoylbenzoic acid methyl ester (CAS 606-28-0, GENOCURE * MBB; (4-methylphenyl)phenylmethanone (CAS 134-84-9 Omnirad MBZ) or 2,4,6-trimethylbenzophenone and 4-methylbenzophenone (CAS 954-16-5 and CAS 134-84-9 (ESACURE TZT) and one or more amine compounds, in particular poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA) in screen printing compositions and mixtures of the following compounds in inkjet top printing compositions: bi) one or more acylphosphine oxide compounds, in particular one or more compounds selected from the group consisting of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (CAS 162881-26-7 (Omnirad 380) and 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide (CAS 84434-11-7, Omnirad TPO-L); or b-ii) one or more α-amino-ketone compounds, in particular α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl) (CAS 886463-10-1 Omnipol 910) and 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone (CAS 2020359-04-8, GENOCURE *FMP); or b-iii) one or more mixtures of one or more benzophenone compounds, in particular one or more compounds selected from the group consisting of 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one (CAS 272460-97-6, Esacure 1001M); 4,4'-bis(diethylamino)benzophenone (CAS 90-93-7, Omnirad EMK), 4-[(4-methylphenyl)thio]phenyl]phenyl-methanone (CAS 83846-85-9, SpeedCure BMS); and [1,1'-biphenyl]-4-ylphenylmethanone (CAS 2128-93-0, Omnirad 4PBZ); or b-iv) one or more glyoxylate compounds, in particular 2-oxo-2-phenylacetic acid methyl ester (CAS 15206-55-0, Omnipol MBF); or bv) one or more benzil diketal compounds, in particular 2,2-dimethoxy-1,2-diphenylethan-1-one (CAS 24650-42-8, Omnirad BDK); or b-vi) one or more oxime ester compounds, in particular 3-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione-2-(O-benzoyloxime) (CAS 1206525-75-8, SpeedCure 8001); or b-vii) one or more titanocene compounds, in particular bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3, Omnirad 784); or b-viii) one or more mixtures of thioxanthone compounds, in particular 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1, Omnirad ITX); or b-ix) one or more coumarin compounds, in particular 3-(4-C 10 -C 13-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one (CAS 2243703-91-3 (ESACURE 3644); or bx) one or more camphorquinone compounds, in particular 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione (CAS 10373-78-1, GENOCURE * CQ) are used in combination with one or more mixtures of the claimed methods.

[0178]

[0177] Contrary to the examples according to the invention (E19-E36), comparative examples (C3-C5) made by the same process as the claimed process except that the compounds in the screen printing composition and the compounds in the top coating inkjet printing composition were of the second embodiment described herein, failed to show any indicia in combination with the dynamic movement of the rolling bar when the substrate was tilted due to the magnetization orientation of the particles in the magnetic field generator of a bright highly reflective area. Comparative examples C3-C5 showed the dynamic movement of the rolling bar when the substrate was tilted due to the magnetization orientation of the particles in the magnetic field generator, but failed to show any indicia due to the absence of a specific compound or compounds absorbing in the range of about 375 nm to about 470 nm in the top curable coating composition.

[0179]

[0178] As shown by the photographs in Fig. 3C (E37-E39), the optical effect layer OEL showing the indicia as well as the magnetic orientation of the particles in the magnetic field generator, the particles, the dynamic movement of the rolling bar when tilting the substrate with bright and highly reflective areas, is characterized by the following: a) one or more benzyl diketal compounds, in particular 2,2-diethoxy-1-phenyl-ethanone (CAS 6175-45-7 GENOCURE 1) in the screen printing composition. * DEAP) and the following compounds in the inkjet top printing composition: bi) one or more oxime ester compounds, in particular 1,2-butanedione, 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) (CAS 1206525-75-8, SpeedCure 8001); or b-ii) one or more titanocene compounds (bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium (CAS 125051-32-3, Omnirad 784); or b-iii) obtained by the claimed process using one or more mixtures of one or more thioxanthone compounds, in particular 2-isopropyl-9H-thioxanthen-9-one (CAS 5495-84-1, Omnirad ITX) and one or more amine compounds, in particular poly(ethylene glycol) bis(p-dimethylaminobenzoate) (CAS 71512-90-8, Omnipol ASA).

[0180]

[0179] Contrary to the examples according to the present invention (E37-E39), comparative example (C6) made by the same process as claimed, except that the compound in the screen printing composition and the compound in the top coating inkjet printing composition did not consist of the third embodiment described herein, did not show the dynamic movement of the rolling bar when tilting the substrate due to the bright and highly reflective areas, combined with the indicia, magnetic orientation of the particles in the magnetic field generator. Comparative example C6 showed the dynamic movement of the rolling bar when tilting the substrate due to the magnetic orientation of the particles in the magnetic field generator, but did not show the indicia due to the absence of the specific compound or compounds absorbing in the range of about 375 nm to about 470 nm in the top curable coating composition.

Claims

1. 1. A method for making an optical effect layer (OEL), said OEL comprising a motif consisting of at least two areas of a single applied and cured layer comprising non-spherical magnetic or magnetisable pigment particles and exhibiting one or more indicia (x30) on a substrate (x20), The method is: a) applying onto a surface of a substrate (x20) a radical radiation curable coating composition comprising non-spherical magnetic or magnetizable pigment particles and one or more photoreactive compounds that do not absorb in the range of 375 nm to 470 nm, said radical radiation curable coating composition being in a first liquid state to form a coating layer (x10); b) after step a), at least partially applying a top coating composition onto the coating layer (x10), said top coating composition being applied in the form of one or more indicia (x30), said top coating composition comprising one or more compounds absorbing in the range of 375 nm to 470 nm; c) partially simultaneously with or after step b), at least partially curing one or more indicia (x30) and one or more areas of the coating layer (x10) below said one or more indicia (x30) with LED curing units (x50) emitting between 375 nm and 470 nm; d) after step c), exposing the coating layer (x10) to a magnetic field of a magnetic field generator in order to orient at least a portion of the non-spherical magnetic or magnetizable pigment particles; e) partially simultaneously with or after step d), at least partially curing the coating layer (x10) in curing units (x60) emitting at least between 250 nm and 320 nm, The radical radiation curable coating composition and the top coating composition are radical curable compositions, 1. A method wherein the one or more photoreactive compounds that do not absorb in the range of 375 nm to 470 nm of the radical radiation curable coating composition of step a) and the one or more compounds that absorb in the range of 375 nm to 470 nm of the top curable coating composition of step b) are selected according to one of the following combinations: i) the one or more photoreactive compounds of the radical radiation curable coating composition of step a) are alpha-hydroxyketone compounds and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of acylphosphine oxide compounds, alpha-amino-ketone compounds, mixtures of one or more benzophenone compounds and one or more amine compounds, glyoxylate compounds, benzil ketal compounds, oxime ester compounds, titanocene compounds, mixtures of one or more thioxanthone compounds and one or more amine compounds, mixtures of one or more coumarin compounds and one or more amine compounds, mixtures of one or more camphorquinone compounds and one or more amine compounds; and mixtures thereof; ii) the one or more photoreactive compounds of the radical radiation curable coating composition of step a) are a mixture of one or more benzophenone compounds different from the benzophenone compound of the top curable coating composition of step b) and one or more amine compounds, wherein the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of acylphosphine oxide compounds, alpha-amino-ketone compounds, benzophenone compounds different from the benzophenones of the radical radiation curable coating composition of step a), glyoxylate compounds, benzil ketal compounds, oxime ester compounds, titanocene compounds, thioxanthone compounds, coumarin compounds, camphorquinone compounds, and mixtures thereof; or iii) the one or more photoreactive compounds of the radical radiation curable coating composition of step a) are benzil ketal compounds different from the benzil ketal compounds of the top curable coating composition of step b), and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of acylphosphine oxide compounds, alpha-amino-ketone compounds, mixtures of one or more benzophenone compounds and one or more amine compounds, glyoxylate compounds, benzil ketal compounds different from the benzil ketal compounds of the top curable coating composition of step a), oxime ester compounds, titanocene compounds, mixtures of one or more thioxanthone compounds and one or more amine compounds, mixtures of one or more coumarin compounds and one or more amine compounds, mixtures of one or more camphorquinone compounds and one or more amine compounds, and mixtures thereof.

2. 2. The method of claim 1, wherein the one or more photoreactive compounds of the radical radiation curable coating composition of step a) that do not absorb in the range of 375 nm to 470 nm and the one or more compounds of the top curable coating composition of step b) that absorb in the range of 375 nm to 470 nm are selected according to one of the following combinations: i) 2-hydroxy-2-methylpropiophenone; 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone; 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one; (1-hydroxycyclohexyl)phenylmethanone; 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one; 1-[2,3-dihydro-1-[4-(1-hydroxy-2-methyl-1-oxopropanone] ar-(1-hydroxy-2-methyl-1-oxopropyl)(1-methylethenyl)-benzene homopolymer; α-(1,1-dimethyl-2-oxo-2-phenylethyl)-ω-hydroxy-poly(oxy-1,2-ethanediyl) (9CI); polymeric alpha-hydroxy-ketones; and mixtures thereof. The one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: i-1) An acylphosphine oxide compound selected from the group consisting of (1,4,6-trimethylbenzoyl)diphenylphosphine oxide; 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide; phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; bis(1,6-dimethoxybenzoyl)(1,4,4-trimethylpentyl)phosphine oxide; ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate; α,α',α''-1,2,3-propanetriyltris[ω-[[phenyl(1,4,6-trimethylbenzoyl)phosphinyl]oxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof; i-2) 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone; 2-(4-methylbenzyl)-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone; 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one; an alpha-amino-ketone compound selected from the group consisting of 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone; α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof; i-3) The benzophenone compound of the radical radiation curable coating composition of step a) is different from the benzophenone compound selected from the group consisting of [1,1'-biphenyl]-4-ylphenylmethanone; 4-(4-methylphenylthio)benzophenone; 4,4'-bis(diethylamino)benzophenone; 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one; and mixtures thereof, and 2-[(1-hydroxyethyl)(methyl)amino]ethan-1-ol, 4-ethoxycarbonyl-N,N-dimethylaniline; 3-methylbutyl 4-(dimethylamino)benzoate; 2-ethylhexyl 4-(dimethylamino)benzoate; 2-dimethylaminoethyl benzoate; 2-butoxyethyl 4-(dimethylamino)benzoate; 1,1'-[(methylimino)di-2,1-ethanediyl]bis[ one or more amine compounds selected from the group consisting of: 4-(dimethylamino)benzoate]; butoxypolypropylene glycol 4-dimethylaminobenzoate; poly(ethylene glycol) bis(p-dimethylaminobenzoate); polymers of 4-(dimethylamino)benzoate with oxirane and 2-methyl-oxirane; polymers of 4-(dimethylamino)benzoate with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol and oxirane; α-hydro-ω-[[4-(dimethylamino)benzoyl]oxy]-poly[oxy(methyl-1,2-ethanediyl)] and 2,2-bis(hydroxymethyl)-1,3-propane tetra-ether (4:1); reaction products of N-methylbenzenamine and 1,1'-[2-ethyl-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-1,3-propanediyl]-2-propenoate ester; and mixtures thereof, i-4) a glyoxylate compound selected from the group consisting of 2-oxo-2-phenylacetic acid methyl ester; 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate; α-(1-oxo-2-phenylacetyl)-ω-[(1-oxo-2-phenylacetyl)oxy]-poly(oxy-1,4-butanediyl); and mixtures thereof. i-5) 2,2-dimethoxy-1,2-diphenylethan-1-one benzyl ketal compound, i-6) 5-[[4-(1-methylethyl)phenyl]thio]-1H-indene-1,2(3H)-dione 2-(O-acetyloxime); 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyloxime); 3-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-propanedione-2-(O-benzoyloxime); 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime); 1-[9-ethyl- oxime ester compounds selected from the group consisting of 6-(1-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime); 3-cyclopentyl-1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]-1-propanone-1-(O-acetyloxime); 1,8-bis(O-acetyloxime)-1,8-bis[9-(1-ethylhexyl)-6-nitro-9H-carbazol-3-yl]-1,8-octanedione; and mixtures thereof. i-7) bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium titanocene compound; i-8) 2-isopropyl-9H-thioxanthen-9-one; 4-(1-methylethyl)-9H-thioxanthen-9-one; 2,4-diethyl-9H-thioxanthen-9-one; 2-chloro-9H-thioxanthen-9-one; 1-Chloro-4-propoxy-9H-thioxanthen-9-one; 1,3-di[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane; 2-[2-[1-[2-[[2-(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxy]-2-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy]ethoxymethyl]propoxy ]ethoxy]ethoxy]ethyl prop-2-enoate; α-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]-ω-[[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-poly(oxy-1,4-butanediyl); 2-thioxanthonyloxyacetic acid; α-[(9-oxo-9H-thioxanthen-4-yl)carbonyl]-ω-[[(9-oxo-9H-thioxanthen-4-yl)carbonyl]oxy]-poly(oxy-1,2-ethanediyl); and oligomeric and polymeric compounds thereof; and mixtures thereof; and the one or more amine compounds are those described in i-3). i-9) 3-(4-C １０ -C １３ -benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one, and one or more amine compounds as described in i-3), i-10) The camphorquinone compound is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione, and one or more amine compounds are those described in i-3), and mixtures thereof; and i-11) mixtures thereof; ii) diphenylmethanone; 2-methylbenzophenone; (4-methylphenyl)phenylmethanone; 2,4,6-Trimethylbenzophenone; 4-Hydroxybenzophenone laurate; α-(1-oxo-2-propenyl)-ω-(4-benzoylphenoxy)-poly(oxy-1,2-ethanediyl) (9CI); Polymers of 2-benzoylbenzoate with oxirane and 2-methyl-oxirane; 2-Benzoylbenzoic acid methyl ester; 2-Ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate; α-(1-benzoylbenzoyl)-ω-[(1-benzoylbenzoyl)oxy]-poly(oxy-1 [α-[(4-benzoylphenoxy)acetyl]-ω-[[2-(4-benzoylphenoxy)acetyl]oxy]-poly(oxy-1,4-butanediyl); 1,3-di[[α-2-(phenylcarbonyl)benzoylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-2-(phenylcarbonyl)benzoylpoly[oxy(1-methylethylene)]]oxymethyl]propane; and polymeric benzophenone derivatives. Benzophenone compounds of the composition, 2-[(1-hydroxyethyl)(methyl)amino]ethan-1-ol; 4-ethoxycarbonyl-N,N-dimethylaniline; 3-methylbutyl 4-(dimethylamino)benzoate; 2-ethylhexyl 4-(dimethylamino)benzoate; 2-dimethylaminoethyl benzoate; 2-butoxyethyl 4-(dimethylamino)benzoate; 1,1'-[(methylimino)di-2,1-ethanediyl]bis[4-(dimethylamino)benzoate]; butoxypropylene glycol 4-dimethyl 4-(dimethylamino)benzoate; poly(ethylene glycol) bis(p-dimethylaminobenzoate); polymers of 4-(dimethylamino)benzoate with oxirane and 2-methyl-oxirane; polymers of 4-(dimethylamino)benzoate with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol and oxirane; α-hydro-ω-[[4-(dimethylamino)benzoyl]oxy]-poly[oxy(methyl-1,2-ethanediyl)] and 2,2-bis(hydroxymethyl)-1,3-propane tetra-ether (4:1);one or more amine compounds selected from the group consisting of reaction products of N-methylbenzenamine and 1,1'-[2-ethyl-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-1,3-propanediyl]-2-propenoate ester; and mixtures thereof; and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: ii-1) the acylphosphine oxide compounds described in i-1), ii-2) alpha-amino-ketone compounds as described under i-2), ii-3) The benzophenone compounds described in i-3), ii-4) Glyoxylate compounds as described in i-4), ii-5) the benzyl ketal compounds described in i-5); ii-6) The oxime ester compounds described in i-6), ii-7) titanocene compounds described in i-7), ii-8) Thioxanthone compounds described in i-8), ii-9) Coumarin compounds described in i-9), ii-10) camphorquinone compounds described in i-10), and ii-11) and mixtures thereof; iii) the benzil ketal compound of the radical radiation curable coating composition of step a) which is 2,2-diethoxyacetophenone; and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: iii-1) the acylphosphine oxide compounds described in i-1); iii-2) alpha-amino-ketone compounds as described under i-2), iii-3) a benzophenone compound as described in i-3) and one or more amine compounds as described in i-3); iii-4) Glyoxylate compounds as described in i-4), iii-5) the benzyl ketal compounds described in i-5); iii-6) The oxime ester compounds described in i-6), iii-7) titanocene compounds described in i-7), iii-8) a thioxanthone compound as described in i-8) and one or more amine compounds as described in i-3); iii-9) a coumarin compound as described in i-9) and one or more amine compounds as described in i-3); iii-10) a camphorquinone compound as described in i-10) and one or more amine compounds as described in i-3), and iii-11) A mixture thereof.

3. 3. The method of claim 2, wherein the one or more photoreactive compounds of the radical radiation curable coating composition of step a) that do not absorb in the range of 375 nm to 470 nm and the one or more compounds of the top curable coating composition of step b) that absorb in the range of 375 nm to 470 nm are selected according to one of the following combinations: i') 2-hydroxy-2-methylpropiophenone; 2-hydroxy-4'-hydroxyethoxy-2-methylpropiophenone; 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2-methylpropan-1-one; (1-hydroxycyclohexyl)phenylmethanone; 2-hydroxy-1-[4-[4-(1-hydroxy-2-methylpropanoyl)phenoxy]phenyl]-2 alpha-hydroxyketones selected from the group consisting of ar-methylpropan-1-one; 1-[2,3-dihydro-1-[4-(1-hydroxy-2-methyl-1-oxopropyl)phenyl]-1,3,3-trimethyl-1H-inden-5-yl]-2-hydroxy-2-methyl-1-propanone; ar-(1-hydroxy-2-methyl-1-oxopropyl)(1-methylethenyl)-benzene homopolymer; and mixtures thereof, The one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: i-1') acylphosphine oxide compounds selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide; phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; bis(1,6-dimethoxybenzoyl)(1,4,4-trimethylpentyl)phosphine oxide; ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate; α,α',α''-1,2,3-propanetriyltris[ω-[[phenyl(1,4,6-trimethylbenzoyl)phosphinyl]oxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof; i-2') 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one; an alpha-amino-ketone compound selected from the group consisting of 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone; α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof; i-3') The benzophenone compound of the radical radiation curable coating composition of step a) is different from the benzophenone compound selected from the group consisting of [1,1'-biphenyl]-4-ylphenylmethanone; 4-(4-methylphenylthio)benzophenone; 4,4'-bis(diethylamino)benzophenone; 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one; and mixtures thereof, and 2-[(1-hydroxyethyl)(methyl)amino]ethan-1-ol; 3-methylbutyl 4-(dimethylamino)benzoate; 2-dimethylaminoethyl benzoate; 2-butoxyethyl 4-(dimethylamino)benzoate; 1,1'-[(methylimino)di-2,1-ethanediyl]bis[4-(dimethylamino)benzoate]; one or more amine compounds selected from the group consisting of 4-(dimethylamino)benzoate, 4-dimethylaminopolypropylene glycol 4-dimethylaminobenzoate; poly(ethylene glycol) bis(p-dimethylaminobenzoate); polymers of 4-(dimethylamino)benzoate with oxirane and 2-methyl-oxirane; polymers of 4-(dimethylamino)benzoate with 2-ethyl-2-(hydroxymethyl)-1,3-propanediol and oxirane; α-hydro-ω-[[4-(dimethylamino)benzoyl]oxy]-poly[oxy(methyl-1,2-ethanediyl)] and 2,2-bis(hydroxymethyl)-1,3-propane tetra-ether (4:1); reaction products of N-methylbenzenamine and 1,1'-[2-ethyl-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-1,3-propanediyl]-2-propenoate ester, i-4') a glyoxylate compound selected from the group consisting of 2-oxo-2-phenylacetic acid methyl ester; 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate; and mixtures thereof; i-5') a benzyl ketal compound which is 2,2-dimethoxy-1,2-diphenylethan-1-one; i-6') an oxime ester compound selected from the group consisting of 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyloxime); 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime); 1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime); 3-cyclopentyl-1-[9-ethyl-6-(1-methylbenzoyl)-9H-carbazol-3-yl]-1-propanone-1-(O-acetyloxime); 1,8-bis(O-acetyloxime)-1,8-bis[9-(1-ethylhexyl)-6-nitro-9H-carbazol-3-yl]-1,8-octanedione; and mixtures thereof. i-7') a titanocene compound which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium; i-8') 2-isopropyl-9H-thioxanthen-9-one; 4-(1-methylethyl)-9H-thioxanthen-9-one; 2,4-diethyl-9H-thioxanthen-9-one; 1-Chloro-4-propoxy-9H-thioxanthen-9-one; 1,3-di[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxy]-2,2-bis[[α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]]oxymethylpropane; 2-[2-[1-[2-[[2-(9-oxothioxanthen-2-yl)oxyacetyl]amino]-3-[1-[2-(1-prop-2-enoyloxyethoxy)ethoxy] thioxanthone compounds selected from the group consisting of α-[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]-ω-[[2-[(9-oxo-9H-thioxanthenyl)oxy]acetyl]oxy]-poly(oxy-1,4-butanediyl); oligomeric and polymeric compounds thereof; and mixtures thereof; and one or more amine compounds as described in i-3′, i-9')3-(4-C １０ -C １３ -benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one, and one or more amine compounds as described in i-3′; i-10') a camphorquinone compound which is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione, and one or more amines described in i-3', and mixtures thereof; and i-11') mixtures thereof; ii') the benzophenone compound of the radical radiation curable coating composition of step a) is selected from the group consisting of diphenylmethanone; (4-methylphenyl)phenylmethanone; 2,4,6-trimethylbenzophenone; 2-benzoylbenzoic acid methyl ester; 2-ethylhexyl 2-([1,1'-biphenyl]-4-ylcarbonyl)benzoate; α-(1-benzoylbenzoyl)-ω-[(1-benzoylbenzoyl)oxy]-poly(oxy-1,2-ethanediyl); [α-[(4-benzoylphenoxy)acetyl]-ω-[[2-(4-benzoylphenoxy)acetyl]oxy]-poly(oxy-1,4-butanediyl) and polymeric benzophenone derivatives; and the one or more amine compounds are selected from the group consisting of those described in i-3'; and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: ii-1′) the acylphosphine oxide compounds described in i-1′), ii-2') alpha-amino-ketone compounds as described under i-2'), ii-3') the benzophenone compounds described in i-3'), ii-4') glyoxylate compounds as described under i-4'), ii-5') benzyl ketal compounds described in i-5'), ii-6') the oxime ester compounds described in i-6'), ii-7') titanocene compounds described in i-7'), ii-8') thioxanthone compounds described in i-8'; ii-9') Coumarin compounds described under i-9'), ii-10') camphorquinone compounds described in i-10'), and ii-11') mixtures thereof; iii') the benzil ketal compound of the radical radiation curable coating composition of step a) which is 2,2-diethoxyacetophenone, and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: iii-1′) acylphosphine oxide compounds described in i-1′), iii-2') alpha-amino-ketone compounds as described under i-2'), iii-3') a benzophenone compound as described in i-3') and one or more amine compounds as described in i-3'); iii-4') Glyoxylate compounds as described under i-4'), iii-5') benzyl ketal compounds described in i-5'), iii-6') the oxime ester compounds described in i-6'), iii-7') titanocene compounds described in i-7'), iii-8') a thioxanthone compound as described in i-8') and one or more amine compounds as described in i-3'); iii-9') a coumarin compound as described in i-9') and one or more amine compounds as described in i-3'); iii-10') a camphorquinone compound as described in i-10') and one or more amine compounds as described in i-3'), and iii-11') A mixture thereof.

4. 4. The method of claim 3, wherein the one or more photoreactive compounds of the radical radiation curable coating composition of step a) that do not absorb in the range of 375 nm to 470 nm and the one or more compounds of the top curable coating composition of step b) that absorb in the range of 375 nm to 470 nm are selected according to one of the following combinations: i″) the alpha-hydroxyketone compound of the radical radiation curable coating composition of step a) selected from the group consisting of 2-hydroxy-2-methylpropiophenone and 2-hydroxy-4′-hydroxyethoxy-2-methylpropiophenone; and mixtures thereof, and the one or more compounds of the top curable coating composition of step b) are from the group consisting of i-1″) an acylphosphine oxide compound selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide; phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; and mixtures thereof; i-2″) alpha-amino-ketone compounds selected from the group consisting of 2-methyl-1-(4-methylsulfanylphenyl)-2-morpholin-4-ylpropan-1-one; 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone; α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof; i-3″) one or more amine compounds which, different from the benzophenone compound of the radical radiation curable coating composition of step a), are selected from the group consisting of 4,4′-bis(diethylamino)benzophenone; and 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one; and mixtures thereof, and poly(ethylene glycol) bis(p-dimethylaminobenzoate); i-4″) a glyoxylate compound selected from the group consisting of 2-2-oxo-2-phenylacetic acid methyl ester; 2-[2-oxo-2-phenyl-acetoxy-ethoxy]ethyl 2-oxo-2-phenylacetate; and mixtures thereof; i-5″) a benzil ketal compound which is 2,2-dimethoxy-1,2-diphenylethan-1-one; i-6″) 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime) oxime ester; i-7″) a titanocene compound which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium; i-8″) a thioxanthone compound which is 2-isopropyl-9H-thioxanthen-9-one; and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate); i-9'')3-(4-C １０ -C １３ a coumarin compound which is (4,4'-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one; one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate); i-10″) a camphorquinone compound which is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione, one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate); and i-11″) mixtures thereof; ii″) the benzophenone compound of the radical radiation curable coating composition of step a) is selected from the group consisting of diphenylmethanone; 2,4,6-trimethylbenzophenone; (4-methylphenyl)phenylmethanone; 2-benzoylbenzoic acid methyl ester; the one or more amine compounds are selected from the group consisting of poly(ethylene glycol) bis(p-dimethylaminobenzoate); and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of ii-1″) an acylphosphine oxide compound selected from the group consisting of 2,4,6-trimethylbenzoyl-ethoxylphenylphosphine oxide; phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; ethyl(3-benzoyl-2,4,6-trimethylbenzoyl)(phenyl)phosphinate; and mixtures thereof; ii-2″) alpha-amino-ketone compounds selected from the group consisting of 1-(9,9-dibutyl-9H-fluoren-2-yl)-2-methyl-2-(4-morpholinyl)-1-propanone; and α-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropyl]-ω-[3-[4-[4-[2-(dimethylamino)-2-(phenylmethyl)-1-oxobutyl]phenyl]-1-piperazinyl]-1-oxopropoxy]-poly(oxy-1,2-ethanediyl); and mixtures thereof. ii-3″) a benzophenone compound selected from the group consisting of [1,1′-biphenyl]-4-ylphenylmethanone; 4-(4-methylphenylthio)benzophenone; 4,4′-bis(diethylamino)benzophenone; 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one; and mixtures thereof; ii-4″) a glyoxylate compound which is 2-2-oxo-2-phenylacetic acid methyl ester; ii-5″) a benzil ketal compound which is 2,2-dimethoxy-1,2-diphenylethan-1-one; ii-6″) an oxime ester compound which is 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime); ii-7″) a titanocene compound which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium; ii-8″) a thioxanthone compound which is 2-isopropyl-9H-thioxanthen-9-one; and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate); ii-9'')3-(4-C １０ -C １３ a coumarin compound which is (-benzoyl)-5,7-dimethoxy-2H-1-benzopyran-2-one; ii-10″) a camphorquinone compound which is 1,7,7-trimethylbicyclo[2.2.1]heptane-2,3-dione, and ii-11″) mixtures thereof; iii″) the benzil ketal compound of the radical radiation curable coating composition of step a) which is 2,2-diethoxyacetophenone, and the one or more compounds of the top curable coating composition of step b) are selected from the group consisting of: iii-6″) an oxime ester compound which is 4-cyclopentyl-1-[4-(phenylthio)phenyl]-1,2-butanedione 2-(O-benzoyloxime); iii-7″) a titanocene compound which is bis(cyclopentadienyl)-bis[2,6-difluoro-3-(pyrrol-1-yl)-phenyl]titanium; iii-8″) a thioxanthone compound which is 2-isopropyl-9H-thioxanthen-9-one; and one or more amine compounds which are poly(ethylene glycol) bis(p-dimethylaminobenzoate), and iii-11″) their mixtures.

5. 5. The method according to claim 1, wherein step d) of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device is carried out for i) uniaxially orienting the pigment particles, ii) biaxially orienting the pigment particles, iii) simultaneously or partially simultaneously orienting the pigment particles uniaxially and biaxially, or iv) biaxially and subsequently uniaxially orienting the pigment particles.

6. 5. The method according to claim 1, further comprising the step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles, said step being carried out subsequent to or partially simultaneously with step b) and prior to step c), said steps being carried out i) to orient the pigment particles uniaxially, ii) to orient the pigment particles biaxially, iii) to orient the pigment particles uniaxially and biaxially simultaneously or partially simultaneously, or iv) to orient the pigment particles biaxially and subsequently uniaxially.

7. 5. The method according to claim 1, further comprising the step of exposing the coating layer (x10) to a magnetic field of a magnetic field generating device in order to orient at least a portion of the magnetic or magnetizable pigment particles, said step being carried out subsequent to step a) and prior to or partially simultaneously with step b), said steps being carried out i) to orient the pigment particles uniaxially, ii) to orient the pigment particles biaxially, iii) to orient the pigment particles uniaxially and biaxially simultaneously or partially simultaneously, or iv) to orient the pigment particles biaxially and subsequently uniaxially.

8. 5. The method of any one of claims 1 to 4, wherein step a) of applying the radical radiation curable coating composition is carried out by a process selected from the group consisting of screen printing, gravure printing, pad printing, and flexographic printing.

9. The method according to any one of claims 1 to 4, wherein step b) of applying the top coating composition is carried out by a non-contact fluid micro-dispensing technique.

10. 5. The method according to any one of claims 1 to 4, wherein at least a part of said non-spherical magnetic or magnetizable particles are constituted by non-spherical optically variable magnetic or magnetizable pigment particles.

11. 11. The method of claim 10, wherein the non-spherical optically variable magnetic or magnetizable pigment particles are selected from the group consisting of magnetic thin film interference pigment particles, magnetic cholesteric liquid crystal pigment particles, and mixtures thereof.

12. 5. The method of any one of claims 1 to 4, wherein the one or more indicia are selected from the group consisting of codes, symbols, alphanumeric symbols, motifs, geometric patterns, letters, words, numbers, logos, figures, portraits, and combinations thereof.

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