METHODS FOR PRODUCING OPTICAL EFFECT LAYERS COMPRISING MAGNETIC OR MAGNETIZABLE PIGMENT PARTICLES

Abstract

METHODS FOR PRODUCING OPTICAL EFFECT LAYERS COMPRISING MAGNETIC OR MAGNETIZABLE PIGMENT PARTICLES. The invention relates to the field of protecting security documents such as banknotes and identity documents against counterfeiting and illegal reproduction.In particular, the present invention provides methods for producing optical effect layers (OELs) exhibiting one or more clues (x30) on a substrate (x20), wherein said method comprises a step of exposing a coating layer (x10) comprising non-spherical magnetic or magnetizable pigment particles to a magnetic field from a magnetic field generating device, so as to orient at least a portion of the magnetic or magnetizable pigment particles; a step of applying a top coating composition over the coating layer (x10) and in the form of one or more clues (x30), and a step of at least partially curing the coating layer (x10) and the one or more clues (x30) with a curing unit (x50).

Description

1 / 91 METHODS FOR PRODUCING OPTICAL EFFECT LAYERS COMPRISING MAGNETIC OR MAGNETIZABLE PIGMENT PARTICLES FIELD OF THE INVENTION

[001] The present invention relates to the field of magnetic field generating devices and methods for producing optical effect layers (OELs) comprising magnetic or magnetizable platelet-shaped pigment particles that are magnetically oriented. In particular, the present invention provides magnetic field generating devices and a method for magnetically orienting magnetic or magnetizable platelet-shaped pigment particles in a coating layer, so as to produce OELs, ​​and the use of said OELs as anti-counterfeiting means in security documents or security articles, as well as for decorative purposes. BACKGROUND OF THE INVENTION

[002] It is known in the art to use inks, compositions, coatings or layers containing oriented particles of magnetic or magnetizable pigment, particularly optically variable magnetic or magnetizable pigment particles, for the production of security elements, for example, in the field of security documents. Coatings or layers comprising oriented particles of magnetic or magnetizable pigment are disclosed, for example, in US documents 2,570,856; US 3,676,273; US 3,791,864; US 5,630,877 and US 5,364,689. Coatings or layers comprising oriented magnetic color-changing pigment particles, which result in particularly attractive optical effects, useful for the protection of security documents, have been disclosed in WO 2002 / 090002 A2 and WO 2005 / 002866 A1.

[003] Security features, for example, for security documents, can generally be classified into “hidden” security features, on the one hand, and “obvious” security features, on the other hand. Petition 870220119653, dated 12 / 19 / 2022, page 16 / 127 2 / 91 The protection provided by hidden security features is based on the principle that such features are difficult to detect, typically requiring specialized equipment and expertise for detection, while overt security features rely on the concept of being easily detectable by unaided human senses; for example, such features may be visible and / or detectable through the sense of touch, although they are still difficult to produce and / or copy. However, the effectiveness of overt security features largely depends on their easy recognition as a security feature.

[004] Magnetic or magnetizable pigment particles in printing inks or coatings enable the production of magnetically induced images, designs, and / or patterns through the application of a correspondingly structured magnetic field, which induces a local orientation of the magnetic or magnetizable pigment particles in the still unhardened (i.e., wet) coating, followed by hardening of the coating. The result is a fixed and stable magnetically induced image, design, or pattern. Materials and technologies for the orientation of magnetic or magnetizable pigment particles in coating compositions have been disclosed, for example, in documents US 2,418,479; US 2,570,856; US 3,791,864, DE 2006848-A, US 3,676,273, US 5,364,689, US 6,103,361, EP 0 406 667 B1; US 2002 / 0160194; US 2004 / 0009308; EP 0 710 508 A1; WO 2002 / 09002 A2; WO 2003 / 000801 A2; WO 2005 / 002866 A1; WO 2006 / 061301 A1. In this way, magnetically induced patterns that are highly resistant to counterfeiting can be produced. The security element in question can only be produced by having access to both the magnetic or magnetizable pigment particles, or corresponding ink, and the particular technology employed to print said ink and to orient said pigment in the printed ink.

[005] With the aim of protecting security documents or articles Petition 870220119653, dated 12 / 19 / 2022, page 17 / 127 3 / 91 which comprise a magnetically induced image protecting it from premature damage caused by dirt and / or moisture over time and use, it has been common practice to apply a protective varnish. These protective varnishes are applied as continuous layers over the prepared and dried / cured magnetically induced image.

[006] Document WO 2011 / 012520 A2 discloses a metal transfer foil comprising a coating layer in the form of a design, wherein said design comprises optically oriented magnetic variable pigment representing an image, clue or pattern. The metal transfer foil may further comprise a top coating layer, wherein said top coating layer is applied prior to the application of the layer comprising the optically variable magnetic pigment. The process for producing said metal transfer foil comprises a) a step of applying the top coating layer, hardening / curing said top coating layer and b) applying the layer comprising the optically variable magnetic pigments, magnetically orienting the particles and hardening / curing said layer.The methods revealed are not suitable for producing magnetically induced images that need to display customized variable cues.

[007] Documents EP 1 641 624 B1, EP 1 937 415 B1 and EP 2 155 498 B1 disclose devices and a method for magnetically transferring evidence to a still-unhardened (i.e., wet) coating composition comprising magnetic or magnetizable pigment particles, so as to form optical effect layers (OELs). The disclosed methods allow the production of security documents and articles that have a customer-specific magnetic design. However, the disclosed magnetic devices are prepared to meet a specific design and cannot be modified if said design needs to be changed from one article to another, and therefore the methods are not suitable Petition 870220119653, dated 12 / 19 / 2022, page 18 / 127 4 / 91 to produce OEL that needs to display custom variable indicators.

[008] Documents EP 3 170 566 B1 and EP 3 459 758 A1, EP 2 542 421 B1 disclose different methods for producing variable evidence in optically variable magnetic ink. However, said methods require the use of special equipment such as a photomask or laser.

[009] With the aim of producing variable information that has magnetic properties in security documents or articles, inkjet inks comprising magnetic particles have been developed to enable Magnetic Ink Character Recognition (MICR). However, said inkjet inks face different challenges, in particular, related to the storage stability of said inks, ink printing capacity, non-homogeneous magnetic ink deposits and printhead clogging. Document EP 2 223 976 B1 discloses a method for producing documents comprising a MICR feature, wherein said method comprises a step of inkjet applying a pattern of a curable ink containing a gelling agent onto a substrate, cooling the ink below the gel temperature of the ink, applying a magnetic material to the ink and finally curing said ink.Alternatively, toners comprising magnetic particles have also been developed and are disclosed, for example, in US documents 10,503,091 B2 and US 10,359,730 B2. However, specific dedicated equipment is required to print such toners.

[0010] Therefore, there remains a need for methods to produce customized optical effect layers that display one or more cues in a versatile manner, but also on an industrial scale, where said optical effect layers exhibit a striking effect. Moreover, said methods must be reliable, easy to implement, and capable of operating at a high production speed. SUMMARY OF THE INVENTION

[0011] Consequently, it is an objective of the present invention Petition 870220119653, dated 12 / 19 / 2022, page 19 / 127 5 / 91 overcome the shortcomings of the previous technique. This is achieved by providing a method for producing an optical effect layer (OEL) that displays one or more cues (x30) on a substrate (x20) comprising the steps of: a) applying to a substrate surface (x20) a radiation-curable coating composition comprising magnetic or magnetizable non-spherical pigment particles, said radiation-curable coating composition being in a first liquid state, so as to form a coating layer (x10); b) expose the coating layer (x10) to a magnetic field from a magnetic field generating device, so as to orient at least a portion of the magnetic or magnetizable pigment particles; c) subsequent to step b), apply a topcoat composition over the coating layer (x10), wherein said topcoat composition is applied in the form of one or more markings (x30), and d) partially simultaneously with or subsequently to step c), cure at least partially the coating layer (x10) and one or more indications (x30) with a curing unit (x50).

[0012] In a preferred embodiment, step b) of exposing the coating layer (x10) is performed so as to orient at least part of the magnetic or magnetizable pigment particles monoaxially. In another preferred embodiment, step b) of exposing the coating layer (x10) is performed so as to orient at least part of the magnetic or magnetizable pigment particles biaxially.

[0013] In a preferred embodiment, step a) of applying the radiation-curable coating composition is performed by a process selected from the group consisting of screen printing, rotogravure printing, pad printing and flexography. Petition 870220119653, dated 12 / 19 / 2022, page 20 / 127 6 / 91

[0014] In a preferred embodiment, step c) of applying the top coating composition is performed by contactless fluid microdispensing technologies, preferably by an inkjet printing process.

[0015] Optical effect layers (OELs) produced by the method described herein are also described in this document, as well as safety documents, decorative elements, and objects comprising one or more optical OELs described herein.

[0016] Also described in this document are methods for manufacturing a security document or a decorative element or object, comprising a) providing a security document or a decorative element or object, and b) providing an optical effect layer such as those described in this document, in particular such as those obtained by the method described in this document, so that it is comprised by the security document or decorative element or object.

[0017] The method described in this document advantageously uses two compositions, wherein said two compositions 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) that exhibit one or more indications in a versatile manner, can be easily implemented on an industrial scale at a high production speed. The two compositions used in the method described in this document comprise, as a first composition, a radiation-curable coating composition comprising non-spherical magnetic or magnetizable pigment particles that is applied to the substrate (x20) and a top coating composition as a second composition that is applied over the radiation-curable coating composition comprising the particles of Petition 870220119653, dated 12 / 19 / 2022, page 21 / 127 7 / 91 pigment and partially overlaps (i.e., overlaps in at least one area) said composition and is applied in the form of one or more indications, when said radiation-curable coating composition is still in a wet, unpolymerized state.

[0018] The present invention provides a reliable and easy-to-implement method for producing eye-catching optical effect layers (OELs) that display one or more of the cues described herein. The disclosed methods advantageously enable the production of security documents and articles that have a customer-specific magnetic design that also displays one or more cues in a versatile, inline-variable, easy-to-implement, and highly reliable manner without requiring customization of the magnetic assemblies used to orient the non-spherical magnetic or magnetizable pigment particles for each variable or customized cue and for each and every customer-specific optical effect layer (OEL). The present invention further provides a reliable and easy-to-implement method for producing eye-catching optical effect layers (OELs) that display one or more of the cues described herein that comprise variable halftones. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The methods described in this document for producing optical effect layers (OELs) exhibiting one or more indications (x30) on the substrate (x20) described in this document are now described in more detail with reference to the drawings and particular embodiments, wherein Fig. 1 schematically illustrates a platelet-shaped pigment particle. Figure 2A schematically illustrates a method for producing an optical effect layer (OEL) that displays one or more cues (230) on a substrate (220) according to the present invention. The method comprises step b) exposing the coating layer (210) to a magnetic field. Petition 870220119653, dated 12 / 19 / 2022, p. 22 / 127 8 / 91 of the magnetic field generating device (B1) so as to monoaxially orient at least part of the magnetic or magnetizable pigment particles; subsequently to step b), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more swatches (230); and step d) of at least partially curing the coating layer (210) and the one or more swatches (230) with a curing unit (250). Fig. 2B schematically illustrates a method for producing an optical effect layer (OEL) that displays one or more clues (230) on a substrate (220) according to the present invention. The method comprises a step b) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), a step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more clues (230); and a step d) of at least partially curing the coating layer (210) and the one or more clues (230) with a curing unit (250). Fig. 2C schematically illustrates a method for producing an optical effect layer (OEL) that displays one or more indentations (230) on a substrate (220) according to the present invention. The method comprises a step b1) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; partially simultaneously with, concurrently with, or subsequently to step b1), a step b2) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially reorient Petition 870220119653, dated 12 / 19 / 2022, page 23 / 127 9 / 91 at least a portion of the magnetic or magnetizable particles in platelet form; subsequent to step b2), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more points (230); and a step d) of at least partially curing the coating layer (210) and the one or more points (230) with a curing unit (250). Figures 2D-1 schematically illustrate a method for producing an optical effect layer (OEL) exhibiting one or more clues (230) on a substrate (220) according to the present invention. The method comprises a step b) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more clues (230);partially simultaneously with or subsequent to step c), step x) of selectively curing at least partially with a selective curing unit (260) one or more first areas of the coating layer (210) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210) and optionally of the top coating (230) remain unexposed to irradiation; subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles of one or more second areas of the coating layer (210); and a step d) of curing at least partially a; Petition 870220119653, dated 12 / 19 / 2022, p. 24 / 127 10 / 91 coating layer (210) and one or more indications (230) with a curing unit (250). Figures 2D-2 schematically illustrate a method for producing an optical effect layer (OEL) exhibiting one or more clues (230) on a substrate (220) according to the present invention. The method comprises a step b) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more clues (230);partially simultaneously with or subsequent to step c), step x) of selectively curing at least partially with a selective curing unit (260) one or more first areas of the coating layer (210) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210) and optionally of the top coating (230) remain unexposed to irradiation; subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles of one or more second areas of the coating layer (210);and a step d) of curing at least partially the coating layer (210) and one or more indications (230) with a curing unit (250).; Figures 2D-3 schematically illustrate a method for producing an optical effect layer (OEL) displaying one or more cues (230) on a substrate (220) according to the present invention. The method Petition 870220119653, dated 12 / 19 / 2022, p. 25 / 127 11 / 91 comprises a step b1) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b1), the step b2) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially reorient at least a portion of the magnetic or magnetizable particles in platelet form; subsequent to step b2), the step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more indentations (230);partially simultaneously with or subsequent to step c), step x) of selectively curing at least partially with a selective curing unit (260) one or more first areas of the coating layer (210) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210) and, optionally, of the top coating (230) remain unexposed to irradiation; subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the third magnetic field generating device (B3) so as to monoaxially reorient at least a portion of the magnetic or magnetizable pigment particles of one or more second areas of the coating layer (210);and a step d) of curing at least partially the coating layer (210) and one or more indications (230) with a curing unit (250).; Figures 2E-1 schematically illustrate a method for producing an optical effect layer (OEL) that displays one or more cues (230) on a substrate (220) according to the present invention. The method comprises a step b) of exposing the coating layer (210) to Petition 870220119653, dated 12 / 19 / 2022, page 26 / 127 12 / 91 magnetic field of the magnetic field generating device (B1) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles; in a manner partially simultaneous with or subsequent to step b), step x) of selectively curing at least partially with a selective curing unit (260) one or more first areas of the coating layer (210) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210) and optionally of the top coating (230) remain unexposed to irradiation;subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) in order to monoaxially reorient at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (210); subsequent to step y), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more points (230); and a step d) of at least partially curing the coating layer (210) and the one or more points (230) with a curing unit (250). Figures 2E-2 schematically illustrate a method for producing an optical effect layer (OEL) exhibiting one or more indentations (230) on a substrate (220) according to the present invention. The method comprises a step b) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; partially simultaneously with or subsequent to step b), a step x) of selectively curing at least partially with a selective curing unit (260) one or more Petition 870220119653, dated 12 / 19 / 2022, p. 27 / 127 13 / 91 first areas of the coating layer (210) of the radiation-curable coating composition of step b) so as to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210), and optionally of the top coating (230), remain unexposed to irradiation; subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles of one or more second areas of the coating layer (210); subsequent to step y), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more indentations (230);and a step d) of curing at least partially the coating layer (210) and one or more indications (230) with a curing unit (250).; Figures 2E-3 schematically illustrate a method for producing an optical effect layer (OEL) that displays one or more indentations (230) on a substrate (220) according to the present invention. The method comprises a step b1) of exposing the coating layer (210) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; simultaneously, partially simultaneously with or subsequently to step b1), a step b2) of exposing the coating layer (210) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially orient at least a portion of the magnetic or magnetizable particles in platelet form; partially simultaneously with or subsequently to step b2), a step x) of selectively curing Petition 870220119653, dated 12 / 19 / 2022, page 28 / 127 14 / 91 at least partially with a selective curing unit (260) one or more first areas of the coating layer (210) of the radiation-curable coating composition of step b) so as to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, and optionally of the top coating (230), so that one or more second areas of the coating layer (210) and optionally of the top coating (230) remain unexposed to irradiation; subsequent to step x), step y) of exposing the coating layer (210) to the magnetic field of the third magnetic field generating device (B3) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles of one or more second areas of the coating layer (210);subsequent to step y), step c) of applying the top coating composition over the coating layer (210), wherein said top coating composition is applied in the form of one or more indentations (230); and a step d) of at least partially curing the coating layer (210) and the one or more indentations (230) with a curing unit (250). Fig. 3 schematically illustrates a magnetic field generating device for biaxially orienting magnetic or magnetizable pigment particles in a coating layer (310) on a substrate (320). Figs. 4A-F schematically illustrate comparative methods for producing an optical effect layer (OEL) on a substrate (420). Figures 5A-E show images of OELs prepared using the method according to the present invention (E1-E21) and prepared according to a comparative method (C1-C11) at two viewing angles (-30° and +30°). DETAILED DESCRIPTION Definitions Petition 870220119653, dated 12 / 19 / 2022, p. 29 / 127 15 / 91

[0020] The following definitions should be used to interpret the meaning of the terms discussed in the description and recited in the claims.

[0021] As used in this document, the term “at least one” is intended to define one or more than one, for example, one or two or three.

[0022] As used in this document, the terms “about” and “substantially” mean that the quantity or value in question may be the specific value designated or some other value adjacent to it. Generally, the terms “about” and “substantially” denote that a certain value is intended to denote a range within ± 5% of the value. As an example, the phrase “about 100” denotes a range of 100 ± 5, that is, the range from 95 to 105. Generally, when the terms “about” and “substantially” are used, it can be expected that similar results or effects according to the invention can be obtained within a range of ±5% of the indicated value.

[0023] The terms “substantially parallel” refer to deviating no more than 10° from the parallel alignment and the terms “substantially perpendicular” refer to deviating no more than 10° from the perpendicular alignment.

[0024] As used in this document, the term “and / or” means that all or only one of the elements of said group may be present. For example, “A and / or B” should mean “only A, or only B, or both A and B”. In the case of “only A”, the term also covers the possibility that B is absent, i.e., “only A, but not B”.

[0025] The term “comprising”, as used in this document, is intended to be non-exclusive and open-ended. Therefore, for example, a coating composition comprising compound A may include other compounds besides A. However, the term “comprising” also covers, as a particular embodiment thereof, the more restrictive meanings of “essentially consisting of” and “consisting of”, of Petition 870220119653, dated 12 / 19 / 2022, p. 30 / 127 16 / 91 so that, for example, “a source solution comprising A, B and optionally C” may also (essentially) consist of A and B, or (essentially) consist of A, B and C.

[0026] The term “optical effect layer (OEL)” as used in this document denotes a coating layer comprising oriented magnetic or magnetizable pigment particles, wherein said magnetic or magnetizable pigment particles are oriented by a magnetic field and wherein the oriented magnetic or magnetizable pigment particles are fixed / frozen in their orientation and position (i.e., after curing) so as to form a magnetically induced image.

[0027] The term coating composition refers to any composition that is capable of forming an optical effect layer (OEL) on a solid substrate and that can be applied preferably, but not exclusively, by a printing method. The coating composition comprises the magnetic or magnetizable platelet-shaped pigment particles described in this document and the binder described in this document.

[0028] As used in this document, the term “wet” refers to a coating layer that is not yet cured, for example, a coating in which the magnetic or magnetizable platelet-shaped pigment particles are still able to change their positions and orientations under the influence of external forces acting upon them.

[0029] The term security document refers to a document that is generally protected against forgery or fraud by at least one security feature. Examples of security documents include, without limitation, valuable documents and valuable commercial goods.

[0030] The term “security feature” is used to denote an image, pattern, or graphic element that can be used for security purposes. Petition 870220119653, dated 12 / 19 / 2022, page 31 / 127 17 / 91 authentication.

[0031] Where the present description refers to “preferred” modes / features, combinations of these preferred modes / features should also be considered as disclosed, provided that such combination of preferred modes / features is technically significant.

[0032] The present invention provides methods for producing optical effect layers (OELs) that exhibit one or more cues (x30) on substrates (x20), wherein said OELs are based on magnetic or magnetizable platelet-shaped magnetic pigment particles that are magnetically oriented and additionally exhibit one or more cues (x30).

[0033] The method described in this document comprises step a) applying to the substrate surface (x20) described in this document the radiation-curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles described in this document, so as to form the coating layer (x10) described in this document, said composition being in a first liquid state that allows its application as a layer and which is in a state not yet cured (i.e., wet) in which the pigment particles can move and rotate within the layer.Since the radiation-curable coating composition described herein must be provided on the substrate surface (x20), the radiation-curable coating composition comprises at least one binder material and magnetic or magnetizable pigment particles, wherein said composition is in a form that allows its processing in the desired printing or coating equipment. Preferably, said step a) is performed by a printing process, preferably selected from the group consisting of screen printing, rotogravure printing, flexography, etching printing (also called in the art etched copper plate printing). Petition 870220119653, dated 12 / 19 / 2022, page 32 / 127 18 / 91 engraving steel matrix printing), pad printing and curtain coating, more preferably selected from the group consisting of intaglio printing, screen printing, rotogravure printing, pad printing and flexography and even more preferably screen printing, rotogravure printing, pad printing and flexography.

[0034] The non-spherical magnetic or magnetizable pigment particles described in this document are preferably magnetic or magnetizable pigment particles in ellipsoid, platelet or needle-shaped form, elongated or flattened, or a mixture of two or more of these, and more preferably platelet-shaped particles.

[0035] The magnetic or magnetizable non-spherical pigment particles described in this document are defined as having, due to their non-spherical shape, non-isotropic reflectivity with respect to incident electromagnetic radiation for which the cured binder material is at least partially transparent. As used in this document, the term “non-isotropic reflectivity” denotes that the proportion of incident radiation from a first angle that is reflected, by a particle, to a certain (viewing) direction (a second angle) is a function of the orientation of the particles, i.e., that a change in the orientation of the particle with respect to the first angle may lead to a different magnitude of reflection to the viewing direction.Preferably, the magnetic or magnetizable non-spherical pigment particles described in this document have a non-isotropic reflectivity with respect to incident electromagnetic radiation in some parts or in the entire wavelength range from about 200 to about 2500 nm, more preferably from about 400 to about 700 nm, such that a change in the orientation of the particle results in a change in reflection by such particle in a certain direction. As is known to those skilled in the art, magnetic pigment particles or... Petition 870220119653, dated 12 / 19 / 2022, p. 33 / 127 The magnetizable pigments described in this document are different from conventional pigments, in that said conventional pigment particles exhibit the same color and reflectivity regardless of particle orientation, whereas the magnetizable or magnetic pigment particles described in this document exhibit a reflection or a color, or both, that depend on particle orientation.

[0036] For embodiments of the method described herein in which step b) or b1) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device described herein is performed so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles, at least a portion of the non-spherical magnetic or magnetizable pigment particles described herein shall consist of platelet-shaped magnetic or magnetizable pigment particles that have an X-axis and a Y-axis that define a predominant extension plane of the particles. 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 that define a predominant extension plane of the particles.In other words, platelet-shaped pigment particles can be considered two-dimensional particles due to the large aspect ratio of their dimensions, as can be seen in Fig. 1. As shown in Fig. 1, a platelet-shaped pigment particle can be considered a two-dimensional structure, where the X and Y dimensions are substantially larger than the Z dimension. Platelet-shaped pigment particles are also called flattened particles or flakes in the art. Such pigment particles can be described with a main geometric axis X, which corresponds to the longest dimension crossing the pigment particle, and a second geometric axis. Petition 870220119653, dated 12 / 19 / 2022, p. 34 / 127 20 / 91 Y perpendicular to X which is also inside said pigment particles.

[0037] The method described in this document comprises step b) exposing the coating layer (x10) to the magnetic field of the magnetic field generating device described in this document so as to orient at least part of the magnetic or magnetizable pigment particles. According to one embodiment, step b) is performed so as to monoaxially orient at least part of the magnetic or magnetizable pigment particles described in this document. According to another embodiment, step b) is performed so as to biaxially orient at least part of the magnetic or magnetizable pigment particles in platelet form, preferably so as to biaxially orient at least part of the magnetic or magnetizable pigment particles in platelet form to have both their geometric X axes and geometric Y axes substantially parallel to the substrate surface.For embodiments in which the method described herein comprises the step of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device described herein in order to biaxially orient at least a portion of the magnetic or magnetizable pigment particle, the coating layer (x10) may be exposed more than once to said magnetic field generating device.

[0038] During the magnetic orientation (step b)) described in this document of the magnetic or magnetizable pigment particles, the substrate (x20) bearing the coating layer (x10) can be placed on a non-magnetic support plate (x40) made of one or more non-magnetic materials.

[0039] During the magnetic orientation (step b)) described in this document of the magnetic pigment particles or Petition 870220119653, dated 12 / 19 / 2022, page 35 / 127 21 / 91 magnetizable, the position of the magnetic field generating devices is not limited and depends on the choice and design of the magnetic orientation pattern to be produced. Therefore, the position of the magnetic field generating devices (B1, B2, B3) in Figs. 2 and 4 is for illustrative purposes only and is not limited. Depending on the choice and design of the magnetic orientation pattern to be produced, the magnetic field generating devices (B1, B2, B3) in Figs. 2 and 4 can be placed below the substrate (x20) or on the coating layer (x10).

[0040] In contrast to a monoaxial orientation in which magnetic or magnetizable pigment particles are oriented such that only their principal geometric axis is constrained by the magnetic field, performing a biaxial orientation means that the platelet-shaped magnetic or magnetizable pigment particles are made to orient such that both of their principal geometric axes are constrained. That is, each platelet-shaped magnetic or magnetizable pigment particle can be considered as having a major geometric axis in the plane of the pigment particle and a minor geometric axis orthogonal to the plane of the pigment particle. The major and minor geometric axes of the platelet-shaped magnetic or magnetizable pigment particles are each forced to orient themselves according to the magnetic field.Effectively, this results in neighboring magnetic platelet-shaped pigment particles, which are close to each other in space, being essentially parallel to each other. Put another way, biaxial orientation aligns the planes of magnetic or magnetizable platelet-shaped pigment particles so that the planes of said pigment particles are oriented to be essentially parallel with respect to the planes of neighboring magnetic or magnetizable platelet-shaped pigment particles (in all directions). The magnetic field generation devices and methods described in this document allow for biaxial orientation of... Petition 870220119653, dated 12 / 19 / 2022, page 36 / 127 22 / 91 magnetic or magnetizable pigment particles in platelet form described in this document, such that the magnetic or magnetizable pigment particles in platelet form a sheet-like structure with their geometric axes X and Y preferably substantially parallel to the substrate surface (x20) and are planarized in said two dimensions.

[0041] Suitable magnetic field generating devices for monoaxially orienting the magnetic or magnetizable pigment particles described in this document are not limited and include, for example, bipolar magnets, quadrupole magnets and combinations thereof. The following devices are provided in this document as illustrative examples.

[0042] Optical effects known as flip-flop effects (also called in the technique switching effect) involve a first printed portion and a second printed portion separated by a transition, wherein pigment particles are aligned parallel to a foreground in the first portion and pigment particles in the second portion are aligned parallel to a background. Methods and magnets for producing said effects are disclosed, for example, in documents US 2005 / 0106367 and EP 1 819 525 B1.

[0043] Optical effects known as scrollbar effects as disclosed in US document 2005 / 0106367 can still be produced. A scrollbar effect is based on the orientation of pigment particles that mimic a curved surface across the coating. The observer sees a zone of specular reflection that moves away from or towards the observer as the image is tilted. The pigment particles are aligned in a curvilinear manner, following a convex curvature (also called negative curve orientation in the technique) or a concave curvature (also called positive curve orientation in the technique). Methods and magnets for producing said effects are Petition 870220119653, dated 12 / 19 / 2022, p. 37 / 127 23 / 91 disclosed, for example, in documents EP 2 263 806 A1, EP 1 674 282 B1, EP 2 263 807 A1, WO 2004 / 007095 A2, WO 2012 / 104098 A1 and WO 2014 / 198905 A2.

[0044] Optical effects known as Venetian blind effects can still be produced. Venetian blind effects involve pigment particles that are oriented so that, along a specific direction of observation, they give visibility to an underlying substrate surface, so that clues or other features present on or in the substrate surface become apparent to the observer while preventing visibility along another direction of observation. Methods and magnets for producing said effects are disclosed, for example, in US documents 8,025,952 and EP 1,819,525 B1.

[0045] Optical effects known as motion ring effects can also be produced. Motion ring effects consist of optically illusory 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 said optical effect layer. Methods and magnets for producing said effects are disclosed, for example, in documents EP 1 710 756 A1, US 8,343,615, EP 2 306 222 A1, EP 2 325 677 A2, WO 2011 / 092502 A2, US 2013 / 084411, WO 2014 108404 A2, and WO2014 / 108303 A1.

[0046] Optical effects that provide an optical impression of a pattern of moving light and dark areas by tilting said effect can also be produced. Methods and magnets for producing said effects are disclosed, for example, in document WO 2013 / 167425 A1.

[0047] Optical effects that provide an optical impression of a loop-shaped body whose size varies according to the inclination of said effect can also be produced. Methods and magnets for producing these optical effects are disclosed, for example, in documents WO 2017 / 064052 A1, WO 2017 / 080698 A1 and WO 2017 / 148789 A1. Petition 870220119653, dated 12 / 19 / 2022, p. 38 / 127 24 / 91

[0048] Optical effects that provide an optical impression of one or more loop-shaped bodies whose shape varies according to the inclination of the optical effect layer can also be produced. Methods and magnets for producing said effects are disclosed, for example, in document WO 2018 / 054819 A1.

[0049] Optical effects that provide an optical impression of a crescent moon moving and rotating by tilting can still be produced. Methods and magnets for producing said effects are disclosed, for example, in document WO 2019 / 215148 A1.

[0050] Optical effects that provide an optical impression of a loop-shaped body whose size and shape vary according to its inclination can be produced. Methods and magnets for producing said effects are disclosed, for example, in the copendente PCT patent application WO 2020 / 052862 A1.

[0051] Optical effects that provide an optical impression of an orthoparallactic effect, that is, in the present case, in the form of a bright reflective vertical bar that moves in a longitudinal direction when the substrate is tilted around a horizontal / latitudinal geometric axis or moves in a horizontal / latitudinal direction when the substrate is tilted around a longitudinal geometric axis, can be produced. Methods and magnets for producing said effects are disclosed, for example, in the copending PCT patent application PCT / EP2020 / 052265.

[0052] Optical effects that provide an optical impression of a loop-shaped body surrounded by one or more loop-shaped bodies, wherein said one or more loop-shaped bodies vary their shape and / or brightness by inclination. Methods and magnets for producing said effects are disclosed, for example, in the copending PCT patent application PCT / EP2020 / 054042.

[0053] Optical effects that give an optical impression of a plurality of dark spots and a plurality of light spots. Petition 870220119653, dated 12 / 19 / 2022, p. 39 / 127 25 / 91 that move and / or appear and / or disappear, not only in a diagonal direction when the substrate is tilted around a vertical / longitudinal geometric axis, but also move and / or appear and / or disappear in a diagonal direction when the substrate is tilted can be produced. Methods and magnets for producing said effects are disclosed, for example, in the copending EP patent applications EP19205715.6 and EP19205716.4.

[0054] The magnetic field generating devices described in this document may be at least partially embedded in a non-magnetic support array, which is made of one or more non-magnetic materials.

[0055] The non-magnetic materials of the non-magnetic support plate (x40) described herein and the non-magnetic support matrix described herein are preferably selected independently from the group consisting of non-magnetic metals and engineering plastics and polymers. Non-magnetic metals include, without limitation, aluminum, aluminum alloys, brass (copper and zinc alloys), titanium, titanium alloys and austenitic steels (i.e., non-magnetic steels).Engineering plastics and polymers include, without limitation, polyaryletherketones (PAEK) and their derivatives polyetheretherketones (PEEK), polyetheretherketoneketones (PEKK), polyetheretherketoneketones (PEEKK) and polyetheretherketoneketone (PEKEKK); polyacetals, polyamides, polyesters, polyethers, copolyetheresters, polyimides, polyetherimides, high-density polyethylene (HDPE), ultra-high molecular weight polyethylene (UHMWPE), polybutylene terephthalate (PBT), polypropylene, acrylonitrile butadiene styrene (ABS) copolymer, fluorinated and perfluorinated polyethylenes, polystyrenes, polycarbonates, polyphenylene sulfide (PPS) and liquid crystal polymers. The preferred materials are PEEK (polyetheretherketone), POM (polyoxymethylene), PTFE (polytetrafluoroethylene), Nylon® (polyamide) and PPS. Petition 870220119653, dated 12 / 19 / 2022, page 40 / 127 26 / 91

[0056] The magnetic field generating devices described in this document may comprise a magnetic plate bearing one or more reliefs, engravings or cuts. Documents WO 2005 / 002866 A1 and WO 2008 / 046702 A1 are examples of such engraved magnetic plates.

[0057] Suitable magnetic field generating devices for biaxially orienting the magnetic or magnetizable platelet-shaped pigment particles described in this document are not limited.

[0058] Particularly preferred devices for biaxially orienting pigment particles are disclosed in document EP 2 157 141 A1. By moving a substrate bearing a coating layer comprising pigment particles, the device disclosed in document EP 2 157 141 A1 provides a dynamic magnetic field that changes its direction, forcing the pigment particles to oscillate rapidly until both principal geometric axes, the X-axis and the Y-axis, become substantially parallel to the substrate surface, i.e., the pigment particles rotate until they reach a stable sheet-like formation with their X and Y geometric axes substantially parallel to the substrate surface and are planarized in said two dimensions.

[0059] Other particularly preferred devices for biaxially orienting pigment particles comprise linear permanent magnet Halbach arrangements, i.e., devices comprising a plurality of magnets with different magnetization directions, and cylindrical devices. A detailed description of Halbach permanent magnets was provided by ZQ Zhu and D. Howe (Halbach Permanent Magnetic Machines and Applications: A Review, IEE. Proc. Electric Power Appl., 2001, 148, pages 299-308). The magnetic field produced by such a Halbach arrangement has the properties that it is concentrated on one side while being Petition 870220119653, dated 12 / 19 / 2022, p. 41 / 127 27 / 91 weakened to almost zero on the other side. Halbach linear arrangements are disclosed, for example, in documents WO 2015 / 086257 A1 and WO 2018 / 019594 A1, and Halbach cylindrical devices are disclosed in document EP 3 224 055 B1.

[0060] Other particularly preferred devices for biaxially orienting pigment particles are rotating magnets, wherein said magnets comprise disc-shaped rotating magnets or magnetic field generating devices that are essentially magnetized along their diameter. Suitable rotating magnets or magnetic field generating devices are described in US patent 2007 / 0172261 A1, said rotating magnets or magnetic field generating devices generate radially symmetric time-varying magnetic fields so as to allow the biaxial orientation of magnetic or magnetizable pigment particles of an uncured coating composition. These magnets or magnetic field generating devices are driven by a shaft (or spindle) connected to an external motor.Document CN 102529326 B discloses examples of devices comprising rotating magnets that may be suitable for biaxially orienting magnetic or magnetizable pigment particles. In a preferred embodiment, devices suitable for biaxially orienting magnetic or magnetizable pigment particles are rotating magnets or axis-free disc-shaped magnetic field generating devices constrained in a housing made of non-magnetic, preferably non-conductive, materials and are driven by one or more coils of magnet wire wound around the housing. Examples of such rotating magnets or axis-free disc-shaped magnetic field generating devices are disclosed in documents WO 2015 / 082344 A1, WO 2016 / 026896 A1 and WO2018 / 141547 A1.

[0061] Other particularly preferred devices for biaxially orienting pigment particles are shown in Fig. 3 and Petition 870220119653, dated 12 / 19 / 2022, p. 42 / 127 28 / 91 comprise a) at least a first set (S1) and a second set (S2), wherein each of the first and second sets (S1, S2) comprises a first bipolar bar magnet having its magnetic geometric axis oriented to be substantially parallel to the substrate during magnetic orientation and two second bipolar bar magnets having their magnetic geometric axes oriented to be substantially perpendicular to the substrate; and b) a pair (P1) of third bipolar bar magnets having their magnetic geometric axes oriented to be substantially parallel to the substrate as those disclosed in the copending European Patent Application EP20176506.2.

[0062] The radiation-curable coating composition described herein, as well as the coating layer (x10) described herein, comprises non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described herein, preferably in an amount of about 5% by weight to about 40% by weight, more preferably about 10% by weight to about 30% by weight, the percentages by weight being based on the total weight of the radiation-curable coating composition or coating layer (x10).

[0063] In the OELs described herein, the magnetic or magnetizable pigment particles described herein are dispersed in a 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 its cured or solid state (also referred to as the second state herein), at least partially transparent to electromagnetic radiation in a wavelength range between 200 nm and 3500 nm, i.e., within the wavelength range that is typically referred to as the “optical spectrum” and that Petition 870220119653, dated 12 / 19 / 2022, page 43 / 127 29 / 91 comprises portions of the infrared, visible, and UV electromagnetic spectrum. Consequently, the particles contained in the binder material in its cured or solid state and its orientation-dependent reflectivity can be perceived through the binder material at some wavelengths within this range. Preferably, the cured binder material is at least partially transparent to electromagnetic radiation in a wavelength range between 200 nm and 800 nm, more preferably between 400 nm and 700 nm.In this document, the term “transparent” denotes that the transmission of electromagnetic radiation through a 20 pm layer of the cured binder material as present in the OEL (excluding the magnetic or magnetizable pigment particles in platelet form, but 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 wavelength(s) in question. This can be determined, for example, by measuring the transmittance of a test piece of the cured binder material (excluding the non-spherical magnetic or magnetizable pigment particles) according to well-established test methods, for example, DIN 5036-3 (1979-11).If OEL serves as a hidden security feature, then typically technical means will be required to detect the (complete) optical effect generated by the OEL under respective lighting conditions comprising the selected non-visible wavelength; wherein said detection requires that the incident radiation wavelength be selected outside the visible range, for example, in the near-UV range.

[0064] Suitable examples of non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described in this document include, without limitation, pigment particles comprising a selected magnetic metal. Petition 870220119653, dated 12 / 19 / 2022, page 44 / 127 30 / 91 of 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 of them; a magnetic oxide of chromium, manganese, cobalt, iron, nickel, or a mixture of two or more of them; or a mixture of two or more of them. The term "magnetic" in reference to metals, alloys, and oxides is directed to ferromagnetic or ferrimagnetic metals, alloys, and oxides. Magnetic oxides of chromium, manganese, cobalt, iron, nickel, or a mixture of two or more of them may be pure oxides or mixtures.Examples of magnetic oxides include, but are not limited to, iron oxides such as hematite (Fe2O3), magnetite (Fe3O4), chromium dioxide (CrO2), magnetic ferrites (MFe2O4), magnetic spinels (MR2O4), magnetic hexaferrites (MFe^Ow), magnetic orthoferrites (RFeO3), magnetic garnets M3R2(AO4)3, where M stands for divalent metal, R stands for trivalent metal and A stands for tetravalent metal.

[0065] Examples of non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described in this document include, without limitation, pigment particles comprising a magnetic layer M made from 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, wherein said magnetic or magnetizable pigment particles may be multilayered structures comprising one or more additional layers.Preferably, one or more additional layers are A layers independently made from one or more selected from the group consisting of metal fluorides such as magnesium fluoride (MgF2), silicon oxide (SiO), silicon dioxide (SiO2), titanium oxide (TiO2) and aluminum oxide (AbO3), more preferably, silicon dioxide (SO2); or B layers independently made from one or more selected from the group consisting of metals and metal alloys, preferably selected from the group consisting of reflective metals and alloys. Petition 870220119653, dated 12 / 19 / 2022, p. 45 / 127 31 / 91 reflective metallic coatings, and more preferably selected from the group consisting of aluminum (Al), chromium (Cr), and nickel (Ni), and even more preferably aluminum (Al); or a combination of one or more A layers as described above in this document and one or more B layers as described above in this document.Typical examples of magnetizable or magnetic platelet-shaped pigment particles that are multilayer structures described above in this document include, without limitation, 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, wherein the A layers, the magnetic M layers, and the B layers are chosen from those described above in this document.

[0066] The radiation-curable coating composition described herein may comprise non-spherical, optically variable magnetic or magnetizable pigment particles, preferably in platelet form, and / or non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, that do not have optically variable properties. Preferably, at least a portion of the magnetic or magnetizable pigment particles described herein consists of non-spherical, optically variable magnetic or magnetizable pigment particles, preferably in platelet form. In addition to the evident safety provided by the color-changing property of the optically variable magnetic or magnetizable pigment particles, which allows for easy detection, recognition, and / or discernment of a security article or document bearing an ink, coating composition Petition 870220119653, dated 12 / 19 / 2022, page 46 / 127 32 / 91 or coating layer comprising the optically variable magnetic or magnetizable pigment particles described in this document, given their potential for forgery using unaided human senses, the optical properties of the optically variable magnetic or magnetizable pigment particles can still be used as a machine-readable tool for OEL recognition. Therefore, the optical properties of the optically variable magnetic or magnetizable pigment particles can simultaneously be used as a hidden or semi-hidden security feature in an authentication process, where the optical (e.g., spectral) properties of the pigment particles are analyzed and thus increase resistance to forgery.

[0067] The use of optically variable, non-spherical magnetic or magnetizable pigment particles, preferably in platelet form in coating layers to produce an 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 commercially available to the public.

[0068] As mentioned above, preferably at least a portion of the non-spherical magnetic or magnetizable pigment particles, preferably platelet-shaped, consists of optically variable non-spherical magnetic or magnetizable pigment particles, preferably platelet-shaped. These are most 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.

[0069] Thin film interference pigment particles Petition 870220119653, dated 12 / 19 / 2022, page 47 / 127 33 / 91 magnetic fields are known to those skilled in the art and are disclosed, for example, in documents US 4,838,648; WO 2002 / 073250 A2; EP 0 686 675 B1; WO 2003 / 000801 A2; US 6,838,166; WO 2007 / 131833 A1; EP 2 402 401 B1; WO 2019 / 103937 A1; WO 2020 / 006286 A1 and the documents cited therein. Preferably, the magnetic thin-film interference pigment particles comprise pigment particles that have a five-layer Fabry-Perot multilayer structure and / or pigment particles that have a six-layer Fabry-Perot multilayer structure and / or pigment particles that have a seven-layer Fabry-Perot multilayer structure and / or pigment particles that have a multilayer structure that combines one or more Fabry-Perot multilayer structures.

[0070] Preferred five-layer Fabry-Perot multilayer structures consist of absorber / dielectric / reflector / dielectric / absorber multilayer structures wherein the reflectors and / or absorbers are also a magnetic layer, preferably the reflectors and / or absorbers are a magnetic layer comprising nickel, iron and / or cobalt, and / or a magnetic alloy comprising nickel, iron and / or cobalt and / or a magnetic oxide comprising nickel (Ni), iron (Fe) and / or cobalt (Co).

[0071] The preferred six-layer Fabry-Perot multilayer structures consist of absorbing / dielectric / reflecting / magnetic / dielectric / absorbing multilayer structures.

[0072] The preferred seven-layer Fabry-Perot multilayer structures consist of absorbing / dielectric / reflecting / magnetic / reflecting / dielectric / absorbing multilayer structures as disclosed in US document 4,838,648.

[0073] Preferred pigment particles that have a multilayered structure combining one or more structures of Petition 870220119653, dated 12 / 19 / 2022, page 48 / 127 34 / 91 Fabry-Perot structures are those described in WO 2019 / 103937 A1 and consist of combinations of at least two Fabry-Perot structures, wherein said two Fabry-Perot structures independently comprise a reflective layer, a dielectric layer and an absorption layer, wherein the reflective and / or absorption layer may each independently comprise one or more magnetic materials and / or wherein a magnetic layer is interposed between the two structures. WO 2020 / 006 / 286 A1 and EP 3 587 500 A1 disclose additional preferred pigment particles having a multilayered structure.

[0074] Preferably, the reflective layers described in this document are made independently from one or more materials 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 selected from the group consisting of aluminum (Al), chromium (Cr), nickel (Ni) and alloys thereof, and even more preferably aluminum (Al).Preferably, the dielectric layers are made independently of one or more materials selected from the group consisting of metal fluorides such as magnesium fluoride (MgF2), aluminum fluoride (AF3), cerium fluoride (CeF3), lanthanum fluoride (LaF3), aluminum and sodium fluorides (e.g., Na3AlF6), neodymium fluoride (NdF3), samarium fluoride (SmF3), barium fluoride (BaF2), calcium fluoride (CaF2), lithium fluoride (LiF) and metal oxides such as silicon dioxide (SiO), silicon dioxide (SiO2), titanium oxide (TO2), aluminum oxide (Al2O3), more preferably selected from the group consisting of magnesium fluoride (MgF2) and silicon dioxide (SiO2) and even more. Petition 870220119653, dated 12 / 19 / 2022, page 49 / 127 35 / 91 preferably magnesium fluoride (MgF2). Preferably, the absorber layers are independently made of one or more 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, and even more preferably selected from the group consisting of chromium (Cr), nickel (Ni) and metal 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 absorbing / dielectric / reflecting / magnetic / reflecting / dielectric / absorbing Fabry-Perot multilayer structure consisting of a Cr / MgF2 / Al / Ni / Al / MgF2 / Cr multilayer structure.

[0075] The magnetic thin-film interference pigment particles described in this document may be multilayer pigment particles that are considered safe for human health and the environment and that are based, for example, on five-layer Fabry-Perot multilayer structures, six-layer Fabry-Perot multilayer structures and seven-layer Fabry-Perot multilayer structures, wherein said pigment particles include one or more magnetic layers comprising a Petition 870220119653, dated 12 / 19 / 2022, page 50 / 127 36 / 91 magnetic alloy having a substantially nickel-free composition that includes about 40% by weight to about 90% by weight of iron, about 10% by weight to about 50% by weight of chromium, and about 0% by weight to about 30% by weight of aluminum. Typical examples of multilayer pigment particles that are considered safe for human health and the environment can be found in document EP 2 402 401 B1, the contents of which are incorporated herein by reference in their entirety.

[0076] Suitable magnetic cholesteric liquid crystal pigment particles exhibiting optically variable characteristics include, without limitation, magnetic monolayer cholesteric liquid crystal pigment particles and magnetic multilayer cholesteric liquid crystal pigment particles. Such pigment particles are disclosed, for example, in documents WO 2006 / 063926 A1, US 6,582,781 and US 6,531,221. Document WO 2006 / 063926 A1 discloses monolayers and pigment particles obtained therefrom with high brightness and color-changing properties with additional particular properties such as magnetizability. The disclosed monolayers and pigment particles, which are obtained therefrom by comminution of said monolayers, include a mixture of three-dimensionally crosslinked cholesteric liquid crystal and magnetic nanoparticles. Documents US 6,582,781 and US 6,410.US Patent 6,531,221 discloses platelet-shaped multilayered cholesterol pigment particles comprising the sequence A1 / B / A2, wherein A1 and A2 may be identical or different, and each comprises at least one cholesterol layer, and B is an interlayer that absorbs all or part of the light transmitted by layers A1 and A2 and imparts magnetic properties to said interlayer. Petition 870220119653, dated 12 / 19 / 2022, page 51 / 127 37 / 91 which comprise pigment particles that confer magnetic properties, and B is a cholesteric layer.

[0077] Suitable interference-coated pigments comprising one or more magnetic materials include, without limitation, structures consisting of a substrate selected from the group consisting of a core coated with one or more layers, wherein at least one of the core or one or more layers has magnetic properties. For example, suitable interference-coated pigments comprising a core made of a magnetic material such as those described above in this document, said core being coated with one or more layers made of one or more metal oxides, or having a structure consisting of a core made of synthetic or natural micas, layered silicates (e.g., talc, kaolin and sericite), glasses (e.g., borosilicates), silicon dioxide (SiO2), aluminum oxides (Al2O3), titanium oxides (TiO2), graphites and mixtures of two or more thereof.Furthermore, one or more additional layers, such as coloring layers, may be present.

[0078] The non-spherical magnetic or magnetizable pigment particles, preferably platelet-shaped, described in this document preferably have a d50 size between about 2 µm and about 50 µm (as measured according to direct optical granulometry).

[0079] The non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described in this document may be surface treated in order to protect them against any deterioration that may occur in the coating composition and coating layer and / or to facilitate their incorporation into said coating composition and coating layer; typically corrosion inhibitors and / or wetting agents may be used. Petition 870220119653, dated 12 / 19 / 2022, page 52 / 127 38 / 91

[0080] As mentioned in this document, the method described herein comprises step d) of at least partially curing the coating layer (x10) to a second state, so as to fix the magnetic or magnetizable pigment particles in their adopted positions and orientations. The first liquid state of the radiation-curable coating composition in which the magnetic or magnetizable pigment particles can move and rotate and the second state in which the magnetic or magnetizable pigment particles are fixed are provided by the use of a certain type of radiation-curable coating composition. For example, the components of the radiation-curable coating composition in addition to the non-spherical magnetic or magnetizable pigment particles may take the form of an ink or radiation-curable coating composition such as those used in security applications, for example, for printing banknotes.The first and second states mentioned above are provided by the use of a material that exhibits an increase in viscosity in reaction to exposure to electromagnetic radiation. That is, when the fluid binder material is cured or solidified, said binder material converts to the second state, in which the non-spherical magnetic or magnetizable pigment particles are fixed in their current positions and orientations and can no longer move or rotate within the binder material. As used in this document, by “curing at least partially the coating layer (x10)”, it is understood that the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, are fixed / frozen in their adopted positions and orientations and can no longer move and rotate (also called in the art “particle gripping”).

[0081] The radiation-curable coating composition used to produce the coating layer (x10) described herein Petition 870220119653, dated 12 / 19 / 2022, p. 53 / 127 39 / 91 document comprises the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described in this document. Radiation curing, in particular UV-Vis curing, advantageously leads to an instantaneous increase in the viscosity of the coating composition after exposure to irradiation, thus preventing any further movement of the pigment particles and consequently any loss of information after the magnetic orientation step. Preferably, the curing step d), partially simultaneously with or subsequent to step c), at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document is performed by irradiation with UV-Visible light (i.e., UV-Vis light radiation curing) or by E-beam (i.e., E-beam radiation curing), more preferably by irradiation with UV-Vis light.According to a preferred embodiment, the radiation-curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described herein is a UV-Vis curable coating composition.

[0082] Preferably, the UV-Vis curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described in this document is a radically curable composition; a cationically curable composition; or a radically and cationically curable composition (referred to in the art as a hybrid). In other words, the UV-Vis curable coating composition preferably comprises monomers and / or oligomers selected from radically curable compounds, cationically curable compounds, and mixtures of radically and cationically curable compounds.

[0083] Cationically curable compositions comprise one or more cationic compounds that are cured by cationic mechanisms. Petition 870220119653, dated 12 / 19 / 2022, page 54 / 127 40 / 91 which typically involve radiation activation of one or more photoinitiators that release cationic species, such as acids, which in turn initiate curing by reacting and / or crosslinking monomers and / or oligomers to harden the coating composition. Preferably, one or more cationically curable compounds are selected from the group consisting of vinyl ethers, propenyl ethers, cyclic ethers such as epoxides, oxethanes and tetrahydrofurans, lactones, cyclic thioethers, vinyl thioethers, propenyl thioethers, hydroxyl-containing compounds and mixtures thereof, preferably cationically curable compounds selected from the group consisting of vinyl ethers, propenyl ethers, cyclic ethers such as epoxides, oxethanes and tetrahydrofurans, lactones and mixtures thereof.

[0084] Radically curable compositions comprise one or more radical compounds that are cured by free radical mechanisms that typically include radiation activation of one or more photoinitiators, thereby generating radicals that in turn initiate polymerization so as to harden the coating composition. Preferably, the radically curable compounds are selected from (meth)acrylates, preferably selected from the group consisting of epoxy (meth)acrylates, (meth)acrylate oils, polyester and polyether (meth)acrylates, aliphatic or aromatic urethane (meth)acrylates, silicone (meth)acrylates, acrylic (meth)acrylates and mixtures thereof. The term “(meth)acrylate” refers to acrylate as well as to the corresponding methacrylate.

[0085] Hybrid curable compositions comprise one or more cationic compounds and one or more radical compounds that are cured by both mechanisms described in this document.

[0086] Depending on the compounds used to prepare UV-Vis curable coating compositions comprising non-spherical magnetic or magnetizable pigment particles, Petition 870220119653, dated 12 / 19 / 2022, p. 55 / 127 41 / 91 preferably in platelet form as described in this document, different photoinitiators may be used. Suitable examples of free radical photoinitiators are known to those skilled in the art and include, without limitation, acetophenones, benzophenones, benzyldimethyl ketals, alpha-aminoketones, alpha-hydroxyketones, phosphine oxides and phosphine oxide derivatives, as well as mixtures of two or more thereof. Suitable examples of cationic photoinitiators are known to those skilled in the art and include, without limitation, onium salts such as organic iodonium salts (e.g., diaryl iodonium salts), oxonium (e.g., triaryloxonium salts) and sulfonium salts (e.g., triarylsulfonium salts), as well as mixtures of two or more thereof. Other examples of useful photoinitiators may be found in standard manuals.It may also be advantageous to include a sensitizer along with one or more photoinitiators in order to achieve efficient cure. Typical examples of suitable photosensitizers include, without limitation, isopropyl thioxanthone (ITX), 1-chloro-2-propoxy thioxanthone (CPTX), 2-chloro-thioxanthone (CTX) and 3,4-diethyl thioxanthone (DETX), polymeric derivatives (such as, for example, multifunctional thioxanthone compounds like Omnipol TX, GENOPOL* TX-2, SpeedCure 7010) and mixtures of two or more thereof. The one or more photoinitiators included in the UV-Vis curable coating compositions are preferably present in a total amount of about 0.1% by weight to about 20% by weight, more preferably about 1% by weight to about 15% by weight, the percentage by weight being based on the total weight of the UV-Vis curable coating compositions.

[0087] The radiation-curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described herein may further comprise one or more color components selected from the group consisting of particles of Petition 870220119653, dated 12 / 19 / 2022, page 56 / 127 42 / 91 organic pigments, inorganic pigment particles and organic dyes and / or one or more additives. The latter include, without limitation, compounds and materials that are used to adjust 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 plasticizers), foaming properties (e.g., antifoaming agents), lubrication properties (waxes, oils), UV stability (photostabilizers), adhesion properties, antistatic properties, storage stability (polymerization inhibitors), etc. The additives described in this document may be present in the coating composition in quantities and forms known in the art, which include so-called nanomaterials, wherein at least one dimension of the additive is in the range of 1 to 1000 nm.

[0088] The radiation-curable coating composition comprising the non-spherical magnetic or magnetizable pigment particles, preferably in platelet form, described herein may further comprise one or more marker substances or markers and / or one or more machine-readable materials selected from the group consisting of magnetic materials (other than the magnetic or magnetizable pigment particles described herein), luminescent materials, electroluminescent materials, upconversion materials, electrically conductive materials and infrared-absorbing materials.As used in this document, the term "machine-readable material" refers to a material that exhibits at least one distinctive property that is detectable by a device or machine, and that can be comprised within a coating, so as to confer a way of authenticating said coating or article comprising said coating by the use of particular equipment for its detection and / or authentication. Petition 870220119653, dated 12 / 19 / 2022, p. 57 / 127 43 / 91

[0089] The 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 the binder material described herein (in particular, the UV-Vis curable coating composition preferably comprises monomers and / or oligomers selected from radically curable compounds, cationically curable compounds, and mixtures of radically and cationically curable compounds), thus forming liquid compositions. When present, one or more photoinitiators may be added to the composition during the dispersion or mixing step of all other ingredients, or may be added at a later stage, i.e., after the formation of the liquid coating composition.

[0090] The method described in this document also comprises, subsequent to step b) described in this document, step c) of applying the topcoat composition described in this document over the coating layer (x10) described in this document. The topcoat composition described in this document is applied in the form of one or more indentations (x30) described in this document and partially overlaps (i.e., overlaps in at least one area) the coating layer (x10) described in this document, wherein the radiation-curable coating composition of the coating layer (x10) is still in a wet and unpolymerized state and the magnetic or magnetizable pigment particles are freely mobile and rotatable.

[0091] Preferably, the time between step b) described in this document and step c) described in this document is less than about 60 seconds, more preferably less than 5 seconds, and even more preferably less than about 2 seconds. Petition 870220119653, dated 12 / 19 / 2022, page 58 / 127 44 / 91 In other words, the step of applying the top coating composition over the coating layer (x10) and in the form of one or more clues (x30) is performed subsequent to step b), where the substrate (x20) bearing the coating layer (x10) has been removed from the magnetic field of the magnetic field generating device.

[0092] As used in this document, the term “clues” means continuous and discontinuous layers consisting of distinguishable markings or signs or patterns. Preferably, the one or more clues (x30) described in this document 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, drawings, portraits and combinations thereof. Examples of codes include encoded marks such as encoded alphanumeric data, a one-dimensional barcode, a two-dimensional barcode, a QR code, data matrix and IR read codes. The one or more clues (x30) described in this document may be solid clues and / or raster clues.

[0093] The top coating composition described herein is applied in the form of one or more of the indices described herein (x30) by an application process, preferably a contactless fluid microdispensing process, preferably selected from the group consisting of spray coating, aerosol jet printing, electrohydrodynamic printing and inkjet printing, more preferably by an inkjet printing process, wherein said inkjet printing processes are variable information printing methods that allow the exclusive production of one or more indices (x30) on or within the optical effect layers (OELs) described herein. The application process is chosen as a function of the design and resolution of the one or more indices to be produced. Petition 870220119653, dated 12 / 19 / 2022, page 59 / 127 45 / 91

[0094] Inkjet printing can be advantageously used to produce optical effect layers (OELs) that exhibit one or more of the cues described herein comprising variable halftones. Inkjet halftone printing is a reprographic technique that simulates continuous-tone images, comprising an infinite number of colors or grays, by applying variable inkjet deposits or grammages.

[0095] Spray coating is a technique that involves forcing the composition through a nozzle where a fine aerosol is formed. A carrier gas and electrostatic charging may be involved to assist in directing the aerosol onto the surface to be printed. Spray printing allows for printing spots and lines. Compositions suitable for spray printing typically have a viscosity between about 10 mPa and about 1 Pa.s (25 °C, 1000 s-1). The print resolution of spray coating is in the millimeter range. Spray printing is described, for example, in FC Krebs, Solar Energy Materials & Solar Cells (2009), 93, page 407.

[0096] Aerosol jet printing (AJP) is an emerging non-contact direct engraving approach aimed at producing fine features on a wide range of substrates. AJP is compatible with a wide range of materials and freeform deposition, allows high resolution (on the order of about 10 micrometers) coupled with a relatively large lift distance (e.g., 1-5 mm), as well as orientation independence. The technology involves aerosol generation using an ultrasonic or pneumatic atomizer to generate an aerosol from compositions that typically have a viscosity between about 1 mPa and about 1 Pa.s (25 °C, 1000 s-1). Aerosol jet printing is described, for example, in NJ Wilkinson et al., The International Journal of Advanced Manufacturing Technology (2019) 105:4599-4619.

[0097] Electrohydrodynamic inkjet printing is a Petition 870220119653, dated 12 / 19 / 2022, pp. 60 / 127 46 / 91 High-resolution inkjet printing technology. Electrohydrodynamic inkjet printing technology uses externally applied electric fields to manipulate droplet sizes, ejection frequencies, and substrate placement to achieve higher resolution than conventional inkjet printing while maintaining high production speeds. Electrohydrodynamic inkjet printing resolution is approximately two orders of magnitude higher than conventional inkjet printing technology; therefore, it can be used for nano- and microscale pattern orientation. Electrohydrodynamic inkjet printing can be used in both DOD (Direct-to-Demand) and continuous modes. Compositions for electrohydrodynamic inkjet printing typically have a viscosity between approximately 1 mPa and approximately 1 Pa.s (25 °C, 1000 s⁻¹). Electrohydrodynamic inkjet printing technology is described, for example, by PV Raje and NC.Murmu, International Journal of Emerging Technology and Advanced Engineering, (2014), 4(5), páginas 174-183.

[0098] Slit matrix coating is a one-dimensional coating technique. Slit matrix coating allows the coating of strips of material which is well suited to producing a multi-layered coating with strips of different materials arranged in layers one on top of the other. The pattern alignment is produced by the coating head which is translated along the direction perpendicular to the direction of movement of the blanket. A slit matrix coating head comprises a mask that defines the slits of the coating head through which the slit matrix coating ink is dispersed. An example of a slit matrix coating head is illustrated in FC Krebs, Solar Energy Materials & Solar Cells (2009), 93, pages 405-406. Suitable compositions for slit matrix coating typically have a viscosity between about 1 mPa.s and about 20 mPa.s (25 °C, 1000 s-1). Petition 870220119653, dated 12 / 19 / 2022, p. 61 / 127 47 / 91

[0099] According to one embodiment, the top coating composition described herein is printed in the form of one or more indentations (x30) described herein by an inkjet printing process, preferably a continuous inkjet (CIJ) 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 contactless printing process in which droplets are produced only when needed for printing and generally by an ejection mechanism rather than destabilizing a jet. Depending on the mechanism used in the print head to produce droplets, DOD printing is divided into piezoimpulse, thermal jet, valve jet (viscosity between about 1 mPa.s and about 1 Pa.s (25 °C, 1000 s-1)) and electrostatic process.

[00100] According to one embodiment, the top coating composition described herein comprises one or more monomers and / or oligomers selected from radically curable compounds, cationically curable compounds, and mixtures of radically and cationically curable compounds such as those described herein for the radiation-curable coating composition comprising the magnetic or magnetizable pigment particles described herein. For embodiments in which the radiation-curable coating composition comprising the magnetic or magnetizable pigment particles is a cationically curable composition, the top coating composition preferably comprises one or more monomers and / or oligomers selected from cationically curable compounds such as those described herein for the radiation-curable coating composition.For applications where the radiation-curable coating composition comprises magnetic pigment particles. Petition 870220119653, dated 12 / 19 / 2022, p. 62 / 127 48 / 91 or magnetizable is a radically curable composition, the top coating composition preferably comprises one or more monomers and / or oligomers selected from radically curable compounds such as those described herein for radiation-curable coating compositions. For embodiments where the radiation-curable coating composition comprising magnetic or magnetizable pigment particles is a hybrid curable composition, the top coating composition preferably comprises one or more monomers and / or oligomers selected from cationically curable compounds and / or monomers and / or oligomers selected from radically curable compounds such as those described herein for radiation-curable coating compositions.For embodiments in which the topcoat composition comprises one or more monomers and / or oligomers selected from radically curable compounds, cationically curable compounds, and mixtures of radically and cationically curable compounds such as those described herein for the radiation-curable coating composition described herein, and in which said topcoat composition is applied by an inkjet printing process, said topcoat composition may further comprise conventional additives and ingredients such as, for example, wetting agents, defoamers, surfactants, (co)solvents, and mixtures thereof that are used in the field of radiation-curable inkjet printing.

[00101] According to another embodiment, the top coating composition described herein comprises one or more solvents. For embodiments in which the top coating composition described herein comprises one or more solvents, an additional heat application step may be performed.

[00102] The top coating composition described in Petition 870220119653, dated 12 / 19 / 2022, page 63 / 127 49 / 91 this document may additionally comprise one or more marker substances or markers and / or one or more machine-readable materials as described for the coating layer (x10) comprising the non-spherical magnetic or magnetizable pigment particles described herein, provided that the size of said substances, markers, materials is suitable for the application process described herein. As described herein, the top coating composition described herein does not comprise magnetic or magnetizable pigment particles.

[00103] The method described in this document further includes step d) of curing, partially simultaneously with or subsequent to step c), at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document. By “partially simultaneously”, it is understood that both steps are partially performed simultaneously, i.e., the times of each step partially overlap. In the context described in this document, when curing is performed partially simultaneously with the application of step c), it should be understood that curing becomes effective after the formation of one or more indications before complete or partial curing.

[00104] For embodiments of the method described herein in which there is no intermediate step (or steps) between step c) of applying the topcoat composition over the coating layer (x10) described herein and step d) of at least partially curing the coating layer (x10) and one or more indentations (x30) with the curing unit (x50) described herein (see, for example, Figs. 2A, 2B, 2C and 2E-1-2E3), the time between said step c) and step d) is preferably between about 0 and 5 minutes, more preferably between about 0 and 1 minute, even more preferably Petition 870220119653, dated 12 / 19 / 2022, p. 64 / 127 50 / 91 between approximately 0 and 10 seconds, and even more preferably between approximately 0 and 5 seconds.

[00105] The at least partial curing step described in this document is an at least partial radiation curing step, and UV-Vis light radiation curing is preferred, as these technologies advantageously lead to very fast curing processes and therefore drastically reduce the preparation time of any article comprising the OEL described in this document. Furthermore, radiation curing has the advantage of producing an almost instantaneous increase in the viscosity of the coating compositions. Radiation curing via photopolymerization is particularly preferred, under the influence of actinic light having a wavelength component in the UV or blue part of the electromagnetic spectrum (typically 200 nm to 650 nm; more preferably, 200 nm to 420 nm).UV-visible curing equipment may comprise a high-power light-emitting diode (LED) lamp, or an arc discharge lamp, such as a medium-pressure mercury arc (MPMA) or a metal vapor arc lamp, as the actinic radiation source. Step d) of at least partially curing the coating layer (x10) and one or more indications (x30) is performed with the curing unit (x50) described. Suitable curing units include UV-visible curing equipment comprising a high-power light-emitting diode (LED) lamp or an arc discharge lamp, such as a medium-pressure mercury arc (MPMA) or a metal vapor arc lamp, as the actinic radiation source.

[00106] Various embodiments for steps b) and y) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device that are described in this document are shown in Figs. 2A-E.

[00107] According to an embodiment shown in Fig. 2A, the Petition 870220119653, dated 12 / 19 / 2022, pp. 65 / 127 The 51 / 91 method described in this document comprises: step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) in order to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), step c) of applying the top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more indications (x30) described herein; and partially simultaneously with or subsequent to step c), step d) of at least partially curing the coating layer (x10) and the one or more indications (x30) with the curing unit (x50) described herein.

[00108] According to an embodiment shown in Fig. 2B, the method described in this document comprises: step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles, wherein said magnetic or magnetizable pigment particles are platelet-shaped magnetic or magnetizable pigment particles that have an X geometric axis and a Y geometric axis that define a predominant extension plane of the particles, preferably said step is performed to biaxially orient at least a portion of the platelet-shaped magnetic or magnetizable pigment particles to have both their X geometric axes and Y geometric axes substantially parallel to the substrate surface; subsequent to step b), step c) of applying the topcoat composition over the coating layer (x10), wherein said topcoat composition is applied in the form of one or more Petition 870220119653, dated 12 / 19 / 2022, pp. 66 / 127 52 / 91 indications (x30) described in this document; and in a manner partially simultaneous with or subsequent to step c), step d) of curing at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document.

[00109] According to one embodiment, the method described in this document comprises: Step b) described in this document consists of two steps, the first step b1) which consists of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles, wherein said magnetic or magnetizable pigment particles are platelet-shaped magnetic or magnetizable pigment particles that have an X geometric axis and a Y geometric axis that define a predominant extension plane of the particles, and the additional step b2) which consists of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially reorient at least a portion of the platelet-shaped magnetic or magnetizable particles, wherein said step b2) is performed partially simultaneously with, simultaneously with, or subsequently to step b1) (see Fig.2C where step b2) is executed subsequent to step b1));. subsequent to step b), step c) of applying the topcoat composition over the coating layer (x10), wherein said topcoat composition is applied in the form of one or more indications (x30) described herein; and partially simultaneously with or subsequent to step c), step d) of at least partially curing the coating layer (x10) and the one or more indications (x30) with the curing unit (x50) described in Petition 870220119653, dated 12 / 19 / 2022, pp. 67 / 127 53 / 91 present document.

[00110] According to another embodiment shown in Figs. 2D- 1. The method described in this document comprises: step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) in order to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), step c) of applying the top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more indications (x30) described in this document; partially simultaneously with or subsequent to step c), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially hydrate at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (x10); and partially simultaneously with or subsequent to step y), a step d) of curing at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described herein, wherein said step y) is performed partially simultaneously. Petition 870220119653, dated 12 / 19 / 2022, pp. 68 / 127 54 / 91 with or before step d).

[00111] According to another embodiment shown in Figs. 2D- 2. The method described in this document comprises: Step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) is performed in such a way as to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; subsequent to step b), step c) of applying the top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more indications (x30) described in this document; partially simultaneously with or subsequent to step c), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially mobilize at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (x10); and so as partially simultaneously with or subsequent to step y), a step d) of curing at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document.

[00112] According to another modality, the method described in Petition 870220119653, dated 12 / 19 / 2022, p. 69 / 127 55 / 91 This document comprises: Step b) consists of the two steps described in this document, the first step b1) consisting of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least part of the magnetic or magnetizable pigment particles and the additional step b2) consists of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially reorient at least part of the magnetic or magnetizable particles in platelet form, wherein said additional step b2) is performed partially simultaneously with, simultaneously with or subsequently to step b1) (see Figs. 2D-3 where step b2) is performed subsequently to step b1)); subsequent to step b), step c) of applying the top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more indications (x30) described in this document; partially simultaneously with or subsequent to step c), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the third magnetic field generating device (B3) so as to monoaxially reorient at least a portion of the magnetic or magnetizable pigment particles of the Petition 870220119653, dated 12 / 19 / 2022, pp. 70 / 127 56 / 91 or more second areas of the coating layer (x10); and partially simultaneously with or subsequently to step y), step d) of curing at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document.

[00113] According to another embodiment shown in Figs. 2E- 1. The method described in this document comprises: Step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) is performed in such a way as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles; partially simultaneously with or subsequent to step b), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) in order to monoaxially reorient at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (x10); subsequent to step y), step c) of applying the topcoat composition over the coating layer (x10), wherein said topcoat composition is applied in the form of one or more indications (x30) described herein; and partially simultaneously with or subsequent to step Petition 870220119653, dated 12 / 19 / 2022, pp. 71 / 127 57 / 91 c), step d) of curing at least partially the coating layer (x10) and one or more indications (x30) with the curing unit (x50) described in this document.

[00114] According to another embodiment shown in Figs. 2E- 2. The method described in this document comprises: step b) of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) in order to biaxially orient at least a portion of the magnetic or magnetizable pigment particles; partially simultaneously with or subsequent to step b), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially disperse at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (x10); subsequent to step y), step c) of applying the topcoat composition over the coating layer (x10), wherein said topcoat composition is applied in the form of one or more indications (x30) described herein; and partially simultaneously with or subsequent to step c), step d) of at least partially curing the coating layer (x10) and the one or more indications (x30) with the curing unit (x50) described in Petition 870220119653, dated 12 / 19 / 2022, pp. 72 / 127 58 / 91 present document.

[00115] According to another embodiment, the method described in this document comprises: step b) which consists of the two steps described in this document, the first step b1) which consists of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device (B1) so as to biaxially orient at least part of the magnetic or magnetizable pigment particles and the additional step b2) which consists of exposing the coating layer (x10) to the magnetic field of the second magnetic field generating device (B2) so as to monoaxially orient at least part of the magnetic or magnetizable particles in platelet form, wherein said additional step b2) is performed partially simultaneously with, simultaneously with or subsequently to step b1) (see Figs. 2E-3 where step b2) is performed subsequently to step b1)); subsequently or partially simultaneously with step b), a step x) of selectively curing at least partially one or more first areas of the coating layer (x10) of the radiation-curable coating composition of step b), so as to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation, said selectively curing step being at least partially performed by the selective curing unit (x60) described in this document; subsequent to step x), a step y) of exposing the coating layer (x10) to the magnetic field of the third magnetic field generating device (B3) so as to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles from one or more secondary areas of the coating layer (x10); Petition 870220119653, dated 12 / 19 / 2022, p. 73 / 127 59 / 91 subsequent to step y), step c) of applying the top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more indications (x30) described herein; and partially simultaneously with or subsequent to step c), step d) of at least partially curing the coating layer (x10) and the one or more indications (x30) with the curing unit (x50) described herein.

[00116] For embodiments described herein comprising step x) of selectively curing at least partially one or more first areas of the coating layer (x10) of the radiation-curable coating composition of step b) or step c), so as to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, such that one or more second areas of the coating layer (x10) remain unexposed to the irradiation described herein, a selective curing unit (x60) is used. Selective curing allows the production of optical effect layers (OELs) exhibiting a motif made of different areas, wherein said different areas have different magnetic orientation patterns.The selective curing unit (x60) may comprise the curing unit (x50) described in this document and one or more fixed or removable photomasks that include one or more voids that correspond to a pattern to be formed as part of the coating layer. Alternatively, the selective curing unit (x60) may be addressable as the scanning laser beam disclosed in document EP 2 468 423 A1, an array of light-emitting diodes (LEDs) disclosed in document WO 2017 / 021504 A1 or an actinic radiation LED source (x41) comprising an array of individually addressable actinic radiation emitters disclosed in copending patent application PCT / EP2019 / 087072. Petition 870220119653, dated 12 / 19 / 2022, pp. 74 / 127 60 / 91

[00117] The present invention provides the methods described herein for producing optical effect layers (OELs) exhibiting one or more indications (x30) on the substrates (x20) described herein and substrates (x20) comprising one or more optical effect layers (OELs) obtained therefrom. The substrate (x20) described herein is preferably selected from the group consisting of papers or other fibrous materials (including woven and non-woven fibrous materials), such as cellulose, paper-containing materials, glasses, metals, ceramics, plastics and polymers, metallized plastics or polymers, composite materials and mixtures or combinations of two or more thereof. Typical paper-like or other fibrous materials are produced from a variety of fibers including, without limitation, abaca, cotton, linen, wood pulp and blends thereof.As is well known to those skilled in the art, cotton and cotton / linen blends are preferred for banknotes, while wood pulp is commonly used in security documents other than banknotes. According to another embodiment, 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 polyethylene (PE) and polypropylene (PP), including biaxially oriented polypropylene (BOPP), polyamides, polyesters, such as poly(ethylene terephthalate) (PET), poly(1,4-butylene terephthalate) (PBT), poly(2,6-ethylene naphthoate) (PEN), and polyvinyl chlorides (PVC). Direct-spun olefin fibers such as those sold under the Tyvek® trademark may also be used as a substrate.Typical examples of metallized plastics or polymers include the plastic or polymer materials described above in this document that have a metal disposed continuously or discontinuously on their surface. Typical examples of metals include, without limitation, aluminum (Al), chromium (Cr), copper (Cu), gold. Petition 870220119653, dated 12 / 19 / 2022, pp. 75 / 127 61 / 91 (Au), silver (Ag), alloys thereof, and combinations of two or more of the aforementioned metals. The metallization of the plastic or polymer materials described above in this document may be carried out by an electrodeposition process, a high-vacuum coating process, or by a cathodic deposition process. Typical examples of composite materials include, without limitation, multilayer structures or laminates of paper and at least one plastic or polymer material such as those described above in this document, as well as plastic and / or polymer fibers incorporated into a paper-like or fibrous material such as those described above in this document. Obviously, the substrate may comprise additional additives known to those skilled in the art, such as fillers, sizing agents, bleaches, processing aids, reinforcing agents, and wet fortifiers, etc.When OELs exhibiting one or more indications (x30) produced in accordance with the present invention are used for decorative or cosmetic purposes including, for example, nail polishes, said OEL may be produced on other types of substrates including nails, artificial nails or other parts of an animal or human being.

[00118] Also described in this document are methods for manufacturing a security document or a decorative element or object, comprising a) providing a security document or a decorative element or object, and b) providing one or more layers of optical effect described in this document, in particular as those obtained by the method described in this document, so that it is comprised by the security document or decorative element or object.

[00119] If the OEL produced according to the present invention is in a security document or article, and with the aim of further increasing the level of security and resistance against counterfeiting and illegal reproduction of said security document or article, the substrate Petition 870220119653, dated 12 / 19 / 2022, pp. 76 / 127 62 / 91 may include printed, coated, laser-marked or laser-perforated markings, watermarks, security threads, fibers, clipboards, luminescent compounds, windows, metallic foils, decals and combinations of two or more thereof. With the same objective of further increasing the level of security and resistance against counterfeiting and illegal reproduction of documents or security articles, the substrate may include one or more marking substances or markers and / or machine-readable substances (e.g., luminescent substances, UV / visible / IR absorbing substances, magnetic substances and combinations thereof).

[00120] If desired, a primer layer may be applied to the substrate before step a). This may enhance the OEL quality described in this document or promote adhesion. Examples of such primer layers may be found in document WO 2010 / 058026 A2.

[00121] In order to increase durability through dirt or chemical resistance and cleaning, and therefore the service life of a security document, article, or decorative element or object comprising the OEL obtained through the method described in this document, or in order to modify its aesthetic appearance (e.g., optical gloss), one or more protective layers may be applied over the OEL. When present, the one or more protective layers are typically made of protective varnishes. The protective varnishes may be radiation-curable compositions, thermal drying compositions, or any combination thereof. Preferably, the one or more protective layers are radiation-curable compositions, more preferably UV-Vis curable compositions. The protective layers are typically applied after the OEL has been formed.

[00122] The present invention further provides optical effect layers (OELs) that exhibit one or more of the features (x30) described herein. Petition 870220119653, dated 12 / 19 / 2022, pp. 77 / 127 63 / 91 document and produced by the methods described in this document. The format of the optical effect layers (OELs) described in this document may be continuous or discontinuous. According to one embodiment, the coating layer format (x10) represents one or more traces, points and / or lines, wherein said traces may have the same format as the one or more traces (x30) made of the top coating composition described in this document or may have a different format.

[00123] An OEL exhibiting one or more of the (x30) indications described in this document may be supplied directly onto a substrate on which it is to remain permanently (such as for banknote applications). Alternatively, an optical effect layer may also be supplied onto a temporary substrate for production purposes, from which the OEL is subsequently removed. This may, for example, facilitate the production of the optical effect layer (OEL), particularly while the binder material is still in its fluid state. Then, after the coating composition for the production of the OEL has cured, the temporary substrate may be removed from the OEL.

[00124] Alternatively, in another embodiment, an adhesive layer may be present on the one exhibiting one or more indications (x30) or may be present on the substrate comprising the OEL, wherein said adhesive layer is on the side of the substrate opposite to the side on which the OEL is provided or on the same side as the OEL and over the OEL. Therefore, an adhesive layer may be applied to the OEL or to the substrate, wherein said adhesive layer is applied after the curing step has been completed. Such an article may be attached to all types of documents or other articles or items without printing or other processes involving machinery and a considerable amount of effort. Alternatively, the substrate described in this document comprising the OEL described in this document may be in the form of a transfer sheet, which may be applied to a document or to a Petition 870220119653, dated 12 / 19 / 2022, pp. 78 / 127 64 / 91 item in a separate transfer step. For this purpose, the substrate is provided with a release coating, in which the OELs are produced as described in this document. One or more adhesive layers may be applied over the optical effect layer thus produced.

[00125] Also described in this document are substrates comprising more than one, i.e., two, three, four, etc., optical effect layers (OELs) obtained by the method described in this document.

[00126] Also described in this document are articles, documents, in particular security documents, decorative elements and decorative objects, comprising the optical effect layer (OEL) produced in accordance with the present invention. The articles, in particular security documents, elements or decorative objects, may comprise more than one (e.g., two, three, etc.) OELs produced in accordance with the present invention.

[00127] As mentioned above in this document, the OEL produced according to the present invention can be used for decorative purposes as well as for protecting and authenticating a security document.

[00128] Typical examples of decorative elements or objects include, but are not limited to, luxury goods, cosmetic packaging, automotive parts, electronic / electrical appliances, furniture, and nail products.

[00129] Security documents include, without limitation, valuable documents and valuable commercial goods. Typical examples of valuable documents include, without limitation, banknotes, deeds, tickets, checks, vouchers, tax labels and labels, agreements and the like, identity documents such as passports, identity cards, visas, driver's licenses, bank cards, credit cards, transaction cards, access documents or cards, entry tickets, tickets Petition 870220119653, dated 12 / 19 / 2022, pp. 79 / 127 65 / 91 public transport documents, academic diplomas or degrees and similar documents, preferably banknotes, identity documents, documents conferring rights, driver's licenses and credit cards. The term valuable commercial goods refers to packaging materials, in particular, for cosmetic articles, nutraceutical articles, pharmaceutical articles, alcohols, tobacco articles, beverages or food, electrical / electronic articles, fabrics or jewelry, i.e., articles that must be protected against counterfeiting and / or illegal reproduction to guarantee the contents of the packaging, such as genuine pharmaceuticals. Examples of such packaging materials include, without limitation, labels, such as authentication mark labels, tamper-evident labels and seals. It is indicated that the disclosed substrates, valuable documents and valuable commercial goods are provided solely for illustrative purposes, without restricting the scope of the invention.

[00130] Alternatively, the optical effect layer (OEL) described in this document can be produced on an auxiliary substrate, such as, for example, a security wire, security strip, sheet, adhesive, window or label, and subsequently transferred to a security document in a separate step.

[00131] A person skilled in the art may imagine various modifications to the specific embodiments described above, without departing from the spirit of the present invention. These modifications are covered by the present invention.

[00132] Furthermore, all documents referred to throughout this descriptive report are incorporated herein by way of reference in their entirety, as set forth in full herein. EXAMPLES

[00133] The present invention is now described in more detail with reference to non-limiting examples. The examples below provide further details for the production of optical effect layers (OELs) that Petition 870220119653, dated 12 / 19 / 2022, pp. 80 / 127 66 / 91 exhibit one or more indications. Four series of combinations of UV-Vis curable screen printing compositions and topcoat inkjet printing compositions were prepared and are described in Tables 1-3. Table 1A: Combination of a radically UV-Vis curable screen printing composition comprising magnetic or magnetizable pigment particles in platelet form and a topcoat inkjet printing composition (E1, E3-E6 and C1-C5). Table 1B: Combination of a radically UV-Vis curable screen printing composition comprising magnetic or magnetizable pigment particles in platelet form and a topcoat inkjet printing composition (E2). Table 1C: Combination of a radically UV-Vis curable screen printing composition comprising magnetic or magnetizable pigment particles in platelet form and a topcoat inkjet printing composition (C11). Table 2: Combination of a cationically curable UV-Vis screen printing composition comprising magnetic or magnetizable pigment particles in platelet form and a topcoat inkjet printing composition (E7-E11, E17, E19-E21 and C6-C10). Table 3: Combination of a hybrid UV-Vis curable screen printing composition comprising magnetic or magnetizable pigment particles in platelet form and a topcoat inkjet printing composition (E12-E16 and E18). Table 1A UV-Vis curable screen printing composition. Top coating inkjet printing composition. Ingredients % by weight. Ingredient % by weight. Epoxyacrylate oligomer (Allnex) 28. GENOMER* 1120. 3,3,5-trimethylcyclohexyl acrylate (Rahn) [CAS No. 86178-38-3] 100. Trimethylolpropane triacrylate monomer (Allnex) [CAS No. 15625-89-5] 19.5 Petition 870220119653, dated 12 / 19 / 2022, pp. 81 / 127 67 / 91 UV-Vis radically curable screen printing composition. Topcoat inkjet printing composition. Ingredients % by weight. Ingredient % by weight. Tripropylene glycol diacrylate monomer (Allnex) [CAS No. 42978-66-5] 20. Genorad* 16 (Rahn). Polymerization inhibitor (Rahn) (CAS No. not available) 1. AEROSIL® 200. Smoked silica (Evonik) (CAS No. not available) 1. SpeedCure TPO-L ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate (Lambson) [CAS No. 84434-11-7] 2. Omnirad 500 (IGM). 50% 1-hydroxycyclohexylphenylketone and 50% benzophenone (BASF) [CAS No. 947-19-3] 119-61-9]] 6 Genocure® EPD ethyl-4-dimethylaminobenzoate (Rahn) [CAS No. 10287-53-3] 2 BYK®371 polyester-modified acrylic functional polydimerylsiloxane solution (BYK) (CAS No. not available) 2 TEGO® Foamex N-dimethylpolysiloxane containing smoked silica (Evonik) (CAS No. not available) 2 magnetic pigment particles (*) 16.5 Viscosity / mPas 570 Viscosity / mPas 3 (*) Optically variable magnetic pigment particles in a 7-layer gold to green platelet shape that have a flake shape with a dso diameter of approximately 10.7 µm and a thickness of approximately 1 µm, obtained from VIAVI Solutions, Santa Rosa, CA. Table 1B Petition 870220119653, dated 12 / 19 / 2022, p. 82 / 127 68 / 91 UV-Vis curable screen printing composition. Top coating inkjet printing composition. Ingredients 0 / / 0 by weight. Ingredient 0 / / 0 by weight. GENOMER* 4316 Aliphatic polyester urethane acrylate (Rahn) 26.0. GENOMER* 1120 3,3,5-trimethylcyclohexyl acrylate (Rahn) [CAS No. 86178-38-3] 100. MIRAMER M3190 Trimethylolpropane triacrylate (EO)g (Rahn) [CAS No. 28961-43-5] 26.2. MIRAMER M282 Polyethylene glycol 200 diacrylate (Rahn) [CAS No. 26570-48-9] 20.2. GENORAD* 16 Polymerization inhibitor (Rahn) (CAS No. not available) 0.5. AEROSIL® 200 Fumed silica (Evonik) (CAS no. not available) 1.3 TEGO® Airex 900 antifoam agent (Evonik) [CAS no. 67762-90-7] 1.0 SpeedCure TPO-L (2,4,6-trimethylbenzoyl) ethyl phenyl phosphinate (Lambson) [CAS no. 84434-11-7] 2.9 Omnirad 1173 2-hydroxy-2-methyl-1-phenyl-propan-1-one) (IGM) [CAS no. 7473-98-5] 5.0 GENOCURE* DETX 2,4-diethyl-thioxanthone (Rahn) [CAS no. 82799-44-8] 0.4 magnetic pigment particles (*) 16,5 Viscosity / mPas 640 Viscosity / mPas 3, (*) Optically variable magnetic pigment particles in a 7-layer gold to green platelet shape that have a flake shape with a dso diameter of approximately 10.7 µm and a thickness of approximately 1 µm, obtained from VIAVI Solutions, Santa Rosa, CA. Table 1C Petition 870220119653, dated 12 / 19 / 2022, p. 83 / 127 69 / 91 UV-Vis radically curable screen printing composition Top coating inkjet printing composition Ingredients % by weight Ingredients % by weight Epoxyacrylate oligomer (Allnex) 28 TPGDA DEC® Tripropylene glycol diacrylate monomer (Rahn) [CAS No. 42978-66-5] 94 Trimethylolpropane triacrylate monomer (Allnex) [CAS No. 15625-89-5] 19.5 Tripropylene glycol diacrylate monomer (Allnex) [CAS No. 42978-66-5] 20 Genorad* 16 (Rahn) Polymerization inhibitor (Rahn) (CAS No. not available) 1 AEROSIL® 200 Smoked silica (Evonik) (CAS No. not available) 1 SpeedCure TPO-L ethyl(2,4,6-trimethylbenzoyl)phenylphosphinate (Lambson) [CAS No. 84434-11-7] 2 Omnirad 500 (IGM) 50% 1-hydroxy-cyclohexyl-phenyl-ketone and 50% benzophenone (BASF) [CAS No. 947-19-3, 119-61-9]] 6 SpeedCure TPO-L (2.4,6-trimethylbenzoyl)phenylphosphinate ethyl (Lambson) [CAS No. 84434-11-7] 6 Genocure® EPD ethyl-4-dimethylaminobenzoate (Rahn) [CAS No. 10287-53-3] 2 BYK®371 polyester-modified acrylic functional polydimerylsiloxane solution (BYK) (CAS No. not available) 2 TEGO® Foamex N-dimethylpolysiloxane containing smoked silica (Evonik) (CAS No. not available) 2 magnetic pigment particles (*) 16.5 Viscosity / mPas 570 Viscosity / mPas 15, (*) optically variable magnetic pigment particles in a 7-layer gold to green platelet shape that have the shape of Petition 870220119653, dated 12 / 19 / 2022, p. 84 / 127 70 / 91 flake with a diameter of approximately 10.7 µm and a thickness of approximately 1 µm, obtained from VIAVI Solutions, Santa Rosa, CA. Table 2 Cationically curable UV-visibly screen printing composition. Top coating inkjet printing composition. Ingredients % by weight. Ingredient 0 / / 0 by weight. UviCure S105ES 7-oxabicyclo[4.1.0]heptane-3-carboxylate of 7oxabicyclo[4.1.0]hept-3-ylmethyla (Lambson) [CAS n° 2386-87-0] 57,6 UviCure S105ES (Lambson) [CAS n° 2386-87-0] 25 Diethylene glycol divinyl ether (BASF) [CAS n° 764-99-8] 4,2 POLYOL R4631 pentaerythritol, ethoxylado and propoxylado (Perstorp) [CAS n° 30374-35-7] 8,4 UviCure S130 3-ethyloxetano-3-methanol (Lambson) [CAS n° 3047-32-3] 4,2 Aerosil® 200 defused silica (Evonik) 1,7 TEGO® Airex 900 anti-sparkling agent (Evonik) [CAS n° 6776290-7] 2,1 Triethylene glycol divinyl ether (BASF) [CAS n° 765-12-8] 75 Omnicat 440 4,4'-dimethyl-diphenyl iodine hexafluorophosphate (IGM) [CAS n° 60565-88-0] 3,4 GENOCURE* ITX 2-isopropyl-9H-thioxanten-9-ona (Rahn) [CAS n° 5495-84-1] 0,4 propylene carbonate [CAS n° 108-32-7] 1,5 magnetic pigment particles (*) 16,5 Viscosity / mPas 960 Viscosity / mPas 6. (*) optically variable magnetic pigment particles in a gold to green platelet shape with 7 layers that have a flake shape with a dso diameter of about 10.7 µm and a thickness of about 1 µm, Petition 870220119653, dated 12 / 19 / 2022, pp. 85 / 127 71 / 91 obtained from VIAVI Solutions, Santa Rosa, CA. Table 3 Hybrid UVVis curable screen printing composition. Top coating inkjet printing composition. Ingredients % by weight. Ingredient 0 / / 0 by weight. UviCure S105ES 7-oxabicyclo[4.1.0]heptane-3-carboxylate of 7oxabicyclo[4.1.0]hept-3-ylmethyla (Lambson) [n° CAS 2386-87-0] 37,2 UviCure S105ES (Lambson) [n° CAS 2386-87-0] 25 éter de diethylene glycol divinílico (BASF) [n° CAS 764-99-8] 4,2 POLYOL R4631 pentaerythritol, ethoxylated and propoxylated (Perstorp) [n° CAS 30374-35-7] 8,4 UviCure S130 3-etiloxetano-3-methanol (Lambson ou Perstorp) [n° CAS 3047-32-3] 4,2 MIRAMER M4004 tetra-acrilato de pentaerythritol (EO)n (Rahn) [n° CAS 51728-26-8] 16.7 Aerosil® 200 defumada silica (Evonik) (CAS no. available) 1.7 TEGO® Airex 900 anti-foaming agent (Evonik) [CAS no. 67762-90-7] 2.0 Omnicat 440 4,4'-dimethyl-diphenyl iodine hexafluorophosphate (IGM) [CAS no. 60565-88-0] 3.4 Triethylene glycol divinyl ether (BASF) [CAS no. 765-12-8] 75 Omnirad 1173 2-hydroxy-2-methyl-1-phenyl-propan-1-one) (IGM) [CAS no. 7473-98-5] 3.8 GENOCURE* ITX iso-propyl-thioxanthone (Rahn) [CAS No. 5495-84- 1] 0.4 propylene carbonate [CAS No. 108-32-7] 1.5. Petition 870220119653, 19 / 12 / 2022, pág. 86 / 127 72 / 91 Hybrid UVVis curable screen printing composition. Top coating inkjet printing composition. Ingredients % by weight. Ingredient 0 / / 0 by weight magnetic pigment particles (*) 16.5 Viscosity / mPas 940 Viscosity / mPas 6 (*) Optically variable magnetic pigment particles in a 7-layer gold to green platelet shape that have a flake shape with a dso diameter of approximately 10.7 µm and a thickness of approximately 1 µm, obtained from VIAVI Solutions, Santa Rosa, CA. Table 4 Primer Composition Ingredients % by weight UviCure S105ES 7-oxabicyclo[4.1.0]heptane-3-carboxylate 7oxabicyclo[4.1.0]hept-3-ylmethyl (Lambson) [CAS No. 2386-87-0] 46.05 VINNOL® H14 / 36 (Wacker Polymer Systems GmbH & Co. KG) (CAS No. not available) 6.2 Divinyl diethylene glycol ether (BASF) [CAS No. 764-99-8] 18.8 EBECRYL® 2959 (epoxy acrylate oligomer) (Allnex) (CAS No. not available) 3.8 Pentaerythritol tetraacrylate (EO)n MIRAMER M4004 (Rahn) [CAS No. 51728-26-8] 3.8 TEGO® Airex 900 antifoaming agent (Evonik) [CAS No. 6776290-7] 0.2 GENORAD* 16 polymerization inhibitor (Rahn) (CAS No. not available) 0.5 AEROSIL® R972 smoked silica post-treated with dimethyldichlorosilane (Evonik) [CAS No. 68 911-44-9] 1.9 Petition 870220119653, dated 12 / 19 / 2022, pp. 87 / 127 73 / 91 Primer Composition Ingredients % by weight ACEMATT® OK 607 High Performance Silica (Evonik) [CAS No. 11 2926-008-8] 5.4 SilForce* UV9388C bis(4-tert-butylphenyl)iodonium hexafluorophosphate (Momentive) [CAS No. 61358-25-6] 1.7 Omnirad 1173-hydroxy-2-methylpropiophenone (IGM) [CAS No. 7473-98-5] 2.3 SpeedCure CPTX 1-chloro-4-propoxythioxanthone (Lambson) [CAS No. 142770-42-1] 0.15 Ethyl 3-ethoxypropionate [CAS No. 763-69-9] 1.6 Teratan 1000 (Invista) [CAS No. 25190-06-1] 5.7 Butanol [CAS No. 71-36-3] 1.9 Viscosity / Pas 0.4 Preparation of compositions

[00134] UV-Vis curable screen printing compositions were independently prepared by mixing the ingredients listed in Tables 1-3 for 10 minutes at 2000 rpm using Dispermat CV-3.

[00135] The topcoat inkjet printing compositions were prepared independently by mixing the ingredients listed in Tables 2-3 for 10 minutes at room temperature and 1000 rpm using a Dispermat (LC220-12).

[00136] The viscosities of the compositions were independently measured at 25 °C on a Brookfield viscometer (model “DV-I Prime”, spindle S27 at 100 rpm for UV-Vis curable screen printing compositions, and S00 at 50 rpm for topcoat inkjet printing compositions) and are given in Tables 1-4. Methods for preparing optical effect layers (OELs) Petition 870220119653, dated 12 / 19 / 2022, pp. 88 / 127 74 / 91

[00137] Optical effect layers (OELs) were prepared according to methods of the invention (E1-E21) and according to comparative methods (C1-C11). Tables 5A-C provide summaries of i) the combination of compositions used during the printing methods, ii) the figure that schematically illustrates the method itself, iii) the substrate on which the UV-Vis curable screen printing composition was applied, and iv) the number of passes in the magnetic field generating device during magnetic biaxial orientation. Table 5A Printing inks described in the Table. Method described in the Fig. Substrate. Number of passes over the magnetic field generation device for biaxial orientation. E1 1A 2B No. 1 3 E2 1B 2B No. 1 3 E3 1A 2B No. 1 12 E4 1A 2B No. 1 3 E5 1A 2C No. 1 3 (B1) E6 1A 2A No. 1 0 (monoaxial orientation only) C1 1A 4A No. 1 0 (no magnet) C2 1A 4B No. 1 3 C3 1A 4C No. 1 3 C4 1A 4D No. 1 3 C5 1A 4E No. 1 0 (monoaxial orientation only) C11 1C 4F No. 1 0 (monoaxial orientation only) Table 5B Printing inks described in the Table. Method described in the Fig. Substrate. Number of passes over the magnetic field generation device. E7 2 2B No. 1 3 E8 2 2B No. 1 12 E9 2 2B No. 1 3 Petition 870220119653, dated 12 / 19 / 2022, pp. 89 / 127 75 / 91 E10 2 2C No. 1 3 (B1) E11 2 2A No. 1 0 (monoaxial orientation only) (without magnet) C7 2 4B No. 1 3 C8 2 4C No. 1 3 C9 2 4D No. 1 3 C10 2 4E No. 1 0 (monoaxial orientation only) Table 5C Printing inks described in the Table. Method described in the Fig. Substrate Number of passes over the magnetic field generation device E12 3 2B No. 1 3 E13 3 2B No. 1 12 E14 3 2B No. 1 3 E15 3 2C No. 1 3 (B1) E16 3 2A No. 1 0 (monoaxial orientation only) E18 3 2B No. 2 3 wherein the substrates (x20) No. 1-3 were as follows: substrate No. 1 is a polymer substrate (Guardian™ from CCL) Secure), substrate no. 2 is a trust paper (Louisenthal BNP 100 g / m2 paper), substrate no. 3 is a trust paper (Louisenthal BNP 100 g / m2 paper) coated by hand screen printing using a T90 screen with a primer composition revealed in Table 4 (primer thickness of 20 µm) which was cured by UV irradiation (two lamps: iron-doped mercury lamp 200 W / cm2 + mercury lamp 200 W / cm2 from 1ST Metz GmbH; 2 passes 100 m / min).

[00138] In Fig. 2A (method according to the invention), the method Petition 870220119653, dated 12 / 19 / 2022, pp. 90 / 127 76 / 91 comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (220) so as to form the coating layer (210), subsequent to step a), step b) of monoaxially orienting at least a portion of the magnetic or magnetizable pigment particles, subsequent to step b), step c) of inkjet printing the top coating inkjet printing composition so as to form the trace (230), and subsequent to step c), step d) of curing the coating layer (210) and the trace (230) with the curing unit (250) so as to form the optical effect layer.

[00139] For all examples made according to the methods according to the invention (E6, E11, E16 and 21), approximately 1.2 seconds elapsed between step b) and step c). For the examples made according to the method according to the invention (E6, E11, E16 and 21), less than 10 seconds elapsed between step c) and step d).

[00140] In Fig. 2B (method according to the invention), the method comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (220) so as to form the coating layer (210), subsequent to step a), step b) of biaxially orienting at least a portion of the magnetic or magnetizable pigment particles, subsequent to step b), step c) of inkjet printing the top coating inkjet printing composition so as to form the ink (230), and subsequent to step c), step d) of curing the coating layer (210) and the ink (230) with the curing unit (250), so as Petition 870220119653, dated 12 / 19 / 2022, pp. 91 / 127 77 / 91 forming the optical effect layer.

[00141] For all examples made according to the methods according to the invention (E1-E4, E7-E9, E12-E14, E17-18, E19) approximately 1.2 seconds elapsed between step b) and step c). Five minutes passed between step c) and step d) for examples E4, E9 and E14. In all other examples E1-E3, E7-8, E12-13, E17-18 and E19, said period was less than 10 seconds.

[00142] In Fig. 2C (method according to the invention), the method comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (220) so as to form the coating layer (210), subsequent to step a), step b) consisting of two steps, wherein the first step b1) consisted of biaxially orienting at least a portion of the magnetic or magnetizable pigment particles and the subsequent step b2) of monoaxially reorienting at least a portion of the magnetic or magnetizable pigment particles, subsequent to step b), step c) of inkjet printing the top coating inkjet printing composition so as to form the ink (230), and subsequent to step c), step d) of curing the coating layer (210) and the ink (230) with the curing unit (250) so as to form the optical effect layer.

[00143] For all examples made according to the methods according to the invention (E5, E10, E15 and E20), approximately 1.2 seconds elapsed between step b2) and step c). For examples made according to the method according to the invention E5, E10, E15 and E20, approximately 1.2 seconds elapsed between step c) and step d).

[00144] In Fig. 4A (comparative method), the method comprised the following steps: Petition 870220119653, dated 12 / 19 / 2022, pp. 92 / 127 78 / 91 step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequently to step a), step c) of inkjet printing the top coating inkjet printing composition so as to form the trace (430), and subsequently to step c), step d) of curing the coating layer (410) and the trace (430) with the curing unit (450) so as to form the optical effect layer.

[00145] For all examples made according to this comparative method (C1 and C6), approximately 1.2 seconds elapsed between step c) and step d).

[00146] Fig. 4B (comparative method), the method comprised the following steps: a) (not shown in Fig.) screen printing of the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequent to a) step c) inkjet printing of the top coating inkjet printing composition so as to form the trace (430), subsequent to c) step b) biaxially orienting at least a portion of the magnetic or magnetizable pigment particles, and subsequent to c) step d) curing the coating layer (410) and the trace (430) so as to form the optical effect layer.

[00147] For all examples made according to this comparative method (C2 and C7), approximately 10 seconds elapsed between step c) and step b), and approximately 2.4 seconds elapsed between step b) and step d). Petition 870220119653, dated 12 / 19 / 2022, pp. 93 / 127 79 / 91

[00148] Fig. 4C (comparative method), the method comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequent to step a), Step b) / b1) of biaxially orienting at least a portion of the magnetic or magnetizable pigment particles, subsequent to step / b1), Step c) of inkjet printing the top coating inkjet printing composition so as to form the inkjet (430), subsequent to step c), Step b2) of monoaxially reorienting at least a portion of the magnetic or magnetizable pigment particles, and subsequent to step b2), Step d) of curing the coating layer (410) and the inkjet (430) with the curing unit (450) so as to form the optical effect layer.

[00149] For all examples made according to this comparative method (C3 and C8), approximately 0.3 seconds elapsed between step b1) and step c), approximately 1.2 seconds elapsed between step c) and step b2), and approximately 3.2 seconds elapsed between step b2) and step d).

[00150] Fig. 4D (comparative method), the method comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequent to step a), step b1) of biaxially orienting at least a portion of the magnetic or magnetizable pigment particles and, subsequent to step b) / b1), step c) of inkjet printing Petition 870220119653, dated 12 / 19 / 2022, pp. 94 / 127 80 / 91 the top coating inkjet printing composition, so as to form the trace (430), subsequent to step c), step b2) of monoaxially reorienting at least a portion of the magnetic or magnetizable pigment particles, and partially simultaneously with step b) / b2), step d) of curing the coating layer (410) and the trace (430) with the curing unit (450), so as to form the optical effect layer.

[00151] For all examples made according to this comparative method (C4 and C9), approximately 0.3 seconds elapsed between step b1) and step c), and approximately 1.2 seconds elapsed between step c) and b2).

[00152] Fig. 4E (comparative method), the method comprised the following steps: Step a) (not shown in Fig.) of screen printing the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequent to step a), Step b) of monoaxially orienting at least a portion of the magnetic or magnetizable pigment particles, partially simultaneously with step b) (i.e., while holding the substrate (420) in the magnetic field (B1) of the magnetic field generating device), Step c) of inkjet printing the top coating inkjet printing composition so as to form the inkjet (430), partially simultaneously with steps b) (i.e., while holding the substrate (420) in the magnetic field (B1) of the magnetic field generating device), but subsequent to step c), Step d) of curing the coating layer (410) and the inkjet (430) with the curing unit (450) so as to form the optical effect layer.

[00153] For all examples made according to this method Petition 870220119653, dated 12 / 19 / 2022, pp. 95 / 127 81 / 91 comparative (C5 and C10), approximately 2.2 seconds elapsed between stage c) and stage d).

[00154] Fig. 4F (comparative method), the method comprised the following steps: a) the screen printing step (not shown in Fig.) of the UV-Vis curable screen printing composition onto the substrate (420) so as to form the coating layer (410), subsequent to said step, b) of monoaxially orienting at least a portion of the magnetic or magnetizable pigment particles, partially simultaneously with step b) (i.e., while holding the substrate (420) in the magnetic field (B1) of the magnetic field generating device), d) of curing the coating layer (410) with the curing unit, subsequent to said step d), c) of inkjet printing the top coating inkjet printing composition so as to form the inkjet print (430), subsequent to said step c), d) of curing the inkjet print (430) with the curing unit.

[00155] For the example done according to this comparative method (C11), approximately 5 seconds elapsed between the last two steps. Screen printing of UV-Vis curable screen printing compositions

[00156] The UV-Vis curable screen printing compositions described in Tables 1-3 were independently applied by hand screen printing using a T90 screen on the substrate (x20) (70 mm x 70 mm) described in Tables 5, so as to form a coating layer (x10) that has the following dimensions: 25 mm x 25 mm and a thickness of about 20 µm. Magnetic orientation of curable screen printing compositions Petition 870220119653, dated 12 / 19 / 2022, pp. 96 / 127 82 / 91 by UV-Vis

[00157] Subsequent to the screen printing step described in this document, the step of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device described herein was performed to orient at least a portion of the magnetic or magnetizable pigment particles. Magnetic field generating device for biaxial orientation (shown in Fig. 3)

[00158] The magnetic field generating device used to biaxially orient at least part of the magnetic or magnetizable pigment particles comprised a) a first set (S1) comprising first bipolar bar magnets (371) and two second bipolar bar magnets (372a and 372b) and a second set (S2) comprising first bipolar bar magnets (371) and two second bipolar bar magnets (372a and 372b) and b) a pair (P1) of third bipolar bar magnets (373a and 373b).

[00159] The uppermost surface of the first bipolar bar magnets (371) of the first and second sets (S1, S2), of the second bipolar bar magnets (372a and 372b) of the first and second sets (S1, S2) and of the third bipolar bar magnets (373a and 373b) of the pair (P1) were level with each other.

[00160] The third bipolar bar magnet (373a) was aligned with the second bipolar bar magnet (372a) of the first set (S1) and with the second bipolar bar magnet (372a) of the second set (S2), so as to form a line. The third bipolar bar magnet (373b) was aligned with the second bipolar bar magnet (372b) of the first set (S1) and with the second bipolar bar magnet (372b) of the second set (S2), so as to form a line.

[00161] The first bipolar bar magnets (371) of the first and second sets (S1, S2) had the following dimensions: first Petition 870220119653, dated 12 / 19 / 2022, pp. 97 / 127 83 / 91 thickness (L1) of 5 mm, first length (L4) of 60 mm and first width (L5) of 40 mm. Each of the second bipolar bar magnets (372a and 372b) of the first and second sets (S1, S2) had the following dimensions: second thickness (L2) of 10 mm, second length (L6) of 40 mm and second width (L7) of 10 mm. Each of the third bipolar bar magnets (373a and 373b) of the pair (P1) had the following dimensions: third thickness (L3) of 10 mm, third length (L8) of 20 mm and third width (L9) of 10 mm.

[00162] The first bipolar bar magnet (371) of the first set (S1) and the second bipolar bar magnets (372a and 372b) of the first set (S1) were aligned to form a column, and the first bipolar bar magnet (371) of the second set (S2) and the second bipolar bar magnets (372a and 372b) of the second set (S2) were aligned to form a column. For each set (S1, S2) and each column described in this document, the first bipolar bar magnets (371) and the two second bipolar bar magnets (372a and 372b) were separated by a second distance (d2) of 2 mm. For each row described in this document, the third bipolar bar magnets (373a and 373b) and the two second bipolar bar magnets (372a) were separated by a third distance (d3) of 2 mm.

[00163] The first bipolar bar magnets (371) of the first and second sets (S1, S2) had their magnetic geometric axis oriented to be substantially parallel to the substrate (320), wherein the first bipolar bar magnet (371) of the first set (S1) had its magnetic direction opposite to the magnetic direction of the first bipolar bar magnet (371) of the second set (S2), and were separated by a first distance (d1) of 24 mm (corresponding to the sum of the third length (L8) and the two third distances (d3)).

[00164] The two second bipolar bar magnets (372a and 372b) of the first and second sets (S1, S2) had their geometric axis Petition 870220119653, dated 12 / 19 / 2022, pp. 98 / 127 84 / 91 magnetic oriented to be substantially perpendicular to the first plane and substantially perpendicular to the substrate (320). The South pole of the second bipolar bar magnet (372a) of the first set (S1) pointed to the first plane and to the substrate (320), the North pole of the second bipolar bar magnet (372b) of the first set (S1) pointed to the substrate (320), the North poles of the first bipolar bar magnets (371) of the first set (S1) pointed to the second bipolar bar magnet (372b) of the first set (S1). The North pole of the second bipolar bar magnet (372a) of the second set (S2) pointed towards the first Plane and towards the substrate (320), the South pole of the second bipolar bar magnet (372b) of the second set (S2) towards the substrate (320), the North poles of the first bipolar bar magnets (371) of the second set (S2) pointed towards the second bipolar bar magnet (372a) of the second set (S2).

[00165] The South pole of the third bipolar bar magnet (373a) pointed towards the second bipolar bar magnet (372a) of the first set (S1), wherein said second bipolar bar magnet (372a) had its South pole pointed towards the substrate (320); and the North pole of the third bipolar bar magnet (373b) pointed towards the second bipolar bar magnet (372b) of the first set (S1), wherein said second bipolar bar magnet (372b) had its North pole pointed towards the substrate (320).

[00166] The first bipolar bar magnets (371) of the first and second sets (S1, S2), the second bipolar bar magnets (372a and 372b) of the first and second sets (S1, S2) and the third bipolar bar magnets (373a and 373b) of the pair (P1) were made of NdFeB N42 and were embedded in a non-magnetic support matrix (not shown) made of polyoxymethylene (POM) which had the following dimensions: 115 mm x 115 mm x 12 mm.

[00167] During magnetic orientation, the substrate (320) bearing the coating layer (310) was placed on a non-magnetic support plate made of POM described above in this document. Petition 870220119653, dated 12 / 19 / 2022, pp. 99 / 127 85 / 91 with the coating layer (310) facing the environment, so as to form an assembly, wherein said non-magnetic support plate (340) had the following dimensions: 180 mm x 130 mm x 2 mm and comprised a centrally aligned passage (48 mm x 48 mm), with the coating layer (310) facing the magnetic field generating device (300). The assembly was moved back and forth as described in Tables 5 in the vicinity of and over the magnetic field generating device (300) at a distance of about 2 mm from the upper surface of said device. Magnetic field generating device for monoaxial orientation.

[00168] The magnetic field generating device used to monoaxially orient at least a portion of the magnetic or magnetizable pigment particles comprised a bipolar bar magnet having a length of about 30 mm, a width of about 24 mm, and a thickness of about 6 mm, wherein said bipolar bar magnet was embedded in a matrix made of POM having the following dimensions: 40 mm x 40 mm x 15 mm. The North-South magnetic geometric axis of the bipolar bar magnet was parallel to the substrate surface (x20) and parallel to the width. The bipolar bar magnet was made of NdFeB N42.

[00169] During magnetic orientation, the substrate (x20) bearing the coating layer (x10) was placed on the non-magnetic support plate made of POM described above in this document with the coating layer (x10) facing the environment, so as to form an assembly. The assembly was placed in close proximity to and above the magnetic field generating device, so that the substrate (x20) was at a distance of about 6 mm from the upper surface of the bipolar bar magnet surface.

[00170] For the methods shown in Figs. 2A, 2C and 4C (device producing magnetic field B2 in Figs. 2C and 4C), the device Petition 870220119653, dated 12 / 19 / 2022, pp. 100 / 127 86 / 91 of magnetic field generation was removed vertically from the substrate surface (x20) opposite the surface bearing the layer (x10) before performing the following step.

[00171] For the methods shown in Figs. 4D and 4E (device that produces the magnetic field B2), the assembly was held over the magnetic field generating device during the following steps. Inkjet printing of topcoat inkjet printing compositions

[00172] The topcoat inkjet printing compositions described in Tables 1-3 were independently applied by DOD inkjet printing using a Kyocera KJ4A-TA printhead (600 dpi) to form clues that have the shape of a rectangle with the following dimensions: 20 mm x 12 mm.

[00173] For examples E1-E18 and for comparative examples C1-C11, the respective topcoat compositions were applied at approximately 4 g / m2.

[00174] For examples E19-E21 (halftone inkjet printing of the topcoat composition), the topcoat composition was applied at approximately 0.4 g / m2, approximately 2.0 g / m2, approximately 4.1 g / m2 and approximately 8.1 g / m2, respectively (see images in Fig 5E, rectangles from top to bottom). Cure the coating layer (x10) made from UV-Vis curable screen printing compositions and the indentations (x30) made from topcoat inkjet printing compositions

[00175] The coating layers (x10) made from the UV-Vis curable screen printing compositions and the inkjet top coating compositions described in Tables 1-3 were cured by exposure to a Phoseon UV LED lamp (Type FireLine 125 x 20 mm, 395 nm, 8 W / cm2) for approximately 0.5 Petition 870220119653, dated 12 / 19 / 2022, pp. 101 / 127 87 / 91 second.

[00176] The coating layer (x10) made from the UV-Vis curable screen printing composition of comparative example C11 was cured by exposure to a Phoseon UV LED lamp (Type FireLine 125 x 20 mm, 395 nm, 8 W / cm2) for about 0.5 seconds and the inkjet print composition made from the top coating of C11 was cured by exposure to a curing unit for about 0.7 seconds (two lamps: 200 W / cm2 iron-doped mercury lamp + 200 W / cm2 mercury lamp from IST Metz GmbH).

[00177] Images of the optical effect layers obtained by the methods according to the invention and by the comparative methods are provided in Figs. 5A-E (Fig. 5A corresponding to the examples in Table 5A; Fig. 5B corresponding to the examples in Table 5B and Fig. 5C corresponding to the examples in Table 5C; Fig. 5D corresponding to example E17 in Table 5B and E18 in Table 5C; Fig. 5E corresponding to examples E19-E21 in Table 5B, the top coating being printed in halftones) at two different viewing angles (-30 °C left; +30 °C right).

[00178] The comparative method shown in Fig. 4A for preparing examples (C1 and C6) and lacking a step of magnetically orienting at least a portion of the magnetic or magnetizable pigment particles provided optical effect layers that have randomly oriented particles without exhibiting one or more clues. The optical effect layers obtained by a method lacking a step that exposes the coating layer (x10) to the magnetic field of the magnetic field generating device so as to orient at least a portion of the particles before the step of applying the top coating composition over the coating layer (x10) in the form of one or more clues (x30), do not exhibit one or more clues.

[00179] The comparative method shown in Fig. 4B for preparing Petition 870220119653, dated 12 / 19 / 2022, pp. 102 / 127 88 / 91 examples (C2 and C7), in which the inkjet printing step was followed by the step of magnetically orienting at least a portion of the magnetic or magnetizable pigment particles (i.e., a method devoid of the curing step, at least partially, subsequent to the inkjet printing step) provided optical effect layers that have biaxially oriented particles that have both their geometric X axes and geometric Y axes substantially parallel to the substrate surface without exhibiting the clues.The optical effect layers obtained by a method in which the step exposing the coating layer (x10) to the magnetic field of the magnetic field generating device so as to orient at least part of the particles is performed subsequent to the step of applying the top coating composition over the coating layer (x10) in the form of one or more clues (x30) without an intermediate step of at least partially curing the top coating composition did not exhibit the one or more clues.

[00180] The comparative methods shown in Figs. 4C and 4D for preparing the examples (C3, C4, C8 and C9), in which the step of magnetically biaxially orienting at least a portion of the magnetic or magnetizable pigment particles was performed before the inkjet printing step, which was then followed by the step of magnetically monoaxially reorienting the particles (i.e., methods devoid of the step of curing at least partially subsequent to the inkjet printing step) provided optical effect layers that have biaxially oriented particles exhibiting a scroll bar upon tilting of said OEL without exhibiting the indications. The optical effect layers obtained by a method in which the step of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device so as to orient at least a portion of the particles subsequent to the step of applying the coating composition Petition 870220119653, dated 12 / 19 / 2022, pp. 103 / 127 89 / 91 superior on the coating layer (x10) in the form of one or more indications (x30) without an intermediate curing step that is at least partially performed subsequent to the step of applying the top coating composition did not exhibit the one or more indications.

[00181] The comparative method shown in Fig. 4E for preparing the examples (C5 and C10), in which the step of orienting at least part of the magnetic or magnetizable pigment particles monoaxially was performed simultaneously with the inkjet printing step and simultaneously with the curing step at least partially (i.e., a method devoid of the curing step at least partially subsequent to the inkjet printing step or a method comprising the step of orienting at least part of the magnetic or magnetizable pigment particles being performed simultaneously or subsequently to the inkjet printing step) provided optical effect layers that have monoaxially oriented particles that exhibit a scroll bar upon tilting of said OEL without exhibiting the indications.The optical effect layers obtained by a method in which the step exposing the coating layer (x10) to the magnetic field of the magnetic field generating device so as to orient at least part of the particles is performed partially simultaneously with the step of applying the top coating composition over the coating layer (x10) in the form of one or more traces (x30) and simultaneously with the curing step at least partially do not exhibit the one or more traces.

[00182] The comparative method shown in Fig. 4F for preparing example C11 in which magnetic or magnetizable pigment particles are oriented and fixed by curing before the inkjet printing step led to an optical effect layer that exhibits a scroll bar upon tilting said OEL without exhibiting one or more indications. Petition 870220119653, dated 12 / 19 / 2022, pp. 104 / 127 90 / 91

[00183] Unlike examples (C1-C11) prepared according to the comparative methods shown in Figs. 4A-4F, examples (E1-E18) prepared according to the methods according to the invention shown in Figs. 2A-2C exhibited not only a striking effect, but also exhibited one or more of the features described in this document.

[00184] The method according to the invention shown in Fig. 2B for preparing the examples (E1-E4, E7-E9, E12-E14 and E17-18), wherein the step of magnetically biaxially orienting at least a portion of the magnetic or magnetizable pigment particles was performed before the inkjet printing step which was then followed by the step of at least partially curing the coating layer (x10) and one or more clues (x30), provided optical effect layers that have biaxially oriented particles that have both their geometric X axes and geometric Y axes substantially parallel to the substrate surface (x20) and exhibit the clues and therefore provided optical effect layers with highly reflective bright areas, as well as the clues.

[00185] The method according to the invention shown in Fig. 2C for preparing the examples (E5, E10 and E15), in which two magnetic orientation steps were performed (i.e., the second step of magnetically reorienting at least a portion of the magnetic or magnetizable pigment particles in a monoaxial manner was performed subsequent to the first step of magnetically orienting at least a portion of the particles in a biaxial manner) before the inkjet printing step, which was then followed by the step of at least partially curing the coating layer (x10) and one or more clues (x30), provided optical effect layers that have biaxially oriented particles that exhibit a scroll bar upon inclination of said OEL and exhibit the clues and thus provided optical effect layers with highly reflective bright areas, as well as the clues. Petition 870220119653, dated 12 / 19 / 2022, pp. 105 / 127 91 / 91

[00186] The method according to the invention shown in Fig. 2A for preparing the examples (E6, E11 and E16), wherein the step of magnetically orienting at least a portion of the magnetic or magnetizable pigment particles monoaxially was performed before the inkjet printing step, which was then followed by the step of curing at least partially the coating layer (x10) and one or more clues (x30), provided optical effect layers that have monoaxially oriented particles that exhibit a scroll bar upon tilting said OEL and exhibit the clues.

[00187] As shown in Figs. 5A-E, combinations of UV-Vis curable screen printing compositions comprising magnetic or magnetizable pigment particles, said compositions, which may be cationically curable, radically curable or hybrid curable compositions, to produce the coating layer (x10) with the top coating inkjet printing compositions to produce one or more clues with the method according to the present invention allowed the preparation of optical effect layers exhibiting one or more clues, wherein said OELs may be produced on different types of substrates. Petition 870220119653, dated 12 / 19 / 2022, pp. 106 / 127

Claims

1 / 4 CLAIMS 1. Method for producing an optical effect layer (OEL) exhibiting one or more clues (x30) on a substrate (x20), the method characterized in that it comprises the steps of: a) applying to a substrate surface (x20) a radiation-curable coating composition comprising magnetic or magnetizable non-spherical pigment particles, said radiation-curable coating composition being in a first liquid state, so as to form a coating layer (x10); b) exposing the coating layer (x10) to a magnetic field from a magnetic field generating device, so as to orient at least a portion of the magnetic or magnetizable pigment particles; c) subsequent to step b), applying a top coating composition over the coating layer (x10), wherein said top coating composition is applied in the form of one or more clues (x30);ed) partially simultaneously with or subsequently to step c), cure at least partially the coating layer (x10) and one or more indications (x30) with a curing unit (x50).; 2. Method according to claim 1, characterized in that step b), of exposing the coating layer (x10), is performed so as to monoaxially orient at least a portion of the non-spherical magnetic or magnetizable pigment particles.

3. Method according to claim 1, characterized in that step b), of exposing the coating layer (x10), is performed so as to biaxially orient at least a portion of the non-spherical magnetic or magnetizable pigment particles, wherein the non-spherical magnetic or magnetizable pigment particles are platelet-shaped magnetic or magnetizable pigment particles that have a geometric axis X and a geometric axis Y that define a predominant extension plane of the particles.

4. Method according to claim 3, characterized in that step b), of exposing the coating layer (x10), is performed so as to biaxially orient at least a portion of the magnetic or magnetizable platelet-shaped pigment particles to have both their geometric X axes and geometric Y axes parallel to the substrate surface.

5. Method according to claim 3 or 4, characterized in that step b) consists of two steps, a first step b1) consisting of exposing the coating layer (x10) to the magnetic field of the magnetic field generating device, so as to biaxially orient at least part of the magnetic or magnetizable platelet-shaped pigment particles; and a further step b2) consisting of exposing the coating layer (x10) to a magnetic field of a second magnetic field generating device, so as to monoaxially orient at least part of the magnetic or magnetizable platelet-shaped particles, wherein said further step b2) is performed partially simultaneously with, simultaneously with or subsequently to step b1).

6. Method, according to any one of claims 1 to 4, characterized in that it further comprises: a step x) of selectively curing, at least partially, one or more first areas of the coating layer (x10), to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation; and a step y) of exposing the coating layer (x10) to a magnetic field from the second magnetic field generating device, wherein said step x) is performed partially simultaneously with or subsequent to step c), and said step y) is performed after said step x) and partially simultaneously with or before step d).

7. Method according to claim 5, characterized in that it further comprises: a step x) of selectively curing, at least partially, one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, such that one or more second areas of the coating layer (x10) remain unexposed to irradiation; and a step y) of exposing the coating layer (x10) to a magnetic field from a third magnetic field generating device, wherein said step x) is performed partially simultaneously with or subsequent to step c), and said step y) is performed after said step x) and partially simultaneously with or before step d).

8. A method according to any one of claims 1 to 4, characterized in that it further comprises: a step x) of selectively curing, at least partially, one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, such that one or more second areas of the coating layer (x10) remain unexposed to irradiation; and a step y) of exposing the coating layer (x10) to a magnetic field from the second magnetic field generating device, wherein said step x) is performed partially simultaneously with or subsequently to step b), and said step y) is performed after said step x) and before step c).

9. Method according to claim 5, characterized in that it further comprises: a step x) of selectively curing, at least partially, one or more first areas of the coating layer (x10) to fix at least a portion of the magnetic or magnetizable particles in their adopted positions and orientations, so that one or more second areas of the coating layer (x10) remain unexposed to irradiation; and a step y) of exposing the coating layer (x10) to a magnetic field from a third magnetic field generating device, wherein said step x) is performed partially simultaneously with or subsequently to step b), and said step y) is performed after said step x) and before step c).

10. Method, according to any one of claims 1 to 9, characterized in that step a), of applying the radiation-curable coating composition, is performed by a process selected from the group consisting of screen printing, rotogravure printing, pad printing and flexography.

11. Method, according to any one of claims 1 to 10, characterized in that step c), of applying the top coating composition, is performed by contactless fluid microdispensing technologies, being an inkjet printing process.

12. A method according to any one of claims 1 to 11, characterized in that at least a portion of the non-spherical magnetic or magnetizable particles consists of optically variable non-spherical magnetic or magnetizable pigment particles.

13. Method according to claim 12, characterized in that optically variable non-spherical magnetic or magnetizable pigment particles are selected from the group consisting of thin-film magnetic interference pigments, magnetic cholesteric liquid crystal pigments and mixtures thereof.

14. Method, according to any one of claims 1 to 13, characterized in that one or more clues is / are selected from the group consisting of codes, symbols, alphanumeric symbols, motifs, geometric patterns, letters, words, numbers, logos, drawings, portraits and combinations thereof. Petition 870260002563, dated 12 / 01 / 2026, p. 20 / 25

Images