FI118041B - Transfer material for transferring optically variable elements to objects protected from the carrier - Google Patents

Abstract

The layer (6) possessing the diffraction structures has the shape of the outline of the element being transferred (2) and rests on the substrate (3) only in parts. The reflecting layer is positioned solely near the diffraction structures and in the form of a metal layer (5) in which are cavities in the form of signs or patterns. The join between layers, between the substrate and the layer possessing the diffraction structures, has a wax-like dividing layer. The layer possessing the diffraction structures is a reaction coating layer of a thermoplastic layer. <IMAGE>

Description

118041

BACKGROUND OF THE INVENTION This invention relates to transfer material for transferring optically variable elements, such as personal protective equipment, the elements on the carrier are separate individual elements and the transfer material comprises a plurality of layers in the region of the elements.

Optically variable elements, such as holograms or interfering layer elements, 10 have, for a variety of reasons, become increasingly important in many fields. Usually, these elements will appear in different colors depending on the viewing angle. However, they may also contain miscellaneous information that is recognized only from specific viewing angles. Holograms and similar diffraction structures have been applied in many ways to protect quite a variety of objects against counterfeiting or other forms of manipulation because the angle dependent effect can only be imitated with unreasonable effort. On the other hand, optically variable elements allow for quick visual inspection and provide good protection, as angle dependent effects cannot be reproduced on a copier.

Reflective holograms are often used to protect security documents such as identity cards or banknotes. They are usually accomplished by the use of special matrices with a surface embossing similar to the diffraction pattern of the hologram, by pressing the surface embossing onto a lacquer layer, followed by metallization and The metallization ensures the brightness of the *: *: hologram so that it is visibly perceptible.

Various possibilities have been suggested for attaching such holograms to security documents in a locally restricted format. One of the most tried-and-tested methods is to produce a separate continuous transfer tape, from which holograms are transferred to a document within the desired outline (DE-A1 33 08 831). The movable layers are applied on a substrate provided with an easily removable separating layer, 30 in reverse order to where they appear later in the document.

, ···. The top layer is an adhesive layer, for example a hot adhesive layer.

• · This adhesive layer is used to bond heat-pressed tape and material together under the influence of heat and pressure (hot pressing). The transfer tape pad can then be removed easily * * \ '* i thanks to the separation layer. The movable surfaces 35 may be delimited either by an adhesive layer imprinted with a predetermined pattern so that the movable layer structure adheres to the document only at specific points, or by a laminating compression die, in which case the contour lines correspond to the movable adhesive. surface, only those areas of the adhesive layer to which pressure and heat are applied (DE-A1 33 08 831) are activated. In subsequent removal of the transfer tape, the hologram layer is released from the transfer tape region of the activated adhesive layer and adheres to the agent. However, this requires that the hologram layer be very thin and relatively light in structure, so as to ensure clear separation of the element from the continuous coating of the transfer tape. This requirement is at odds with the general desire for holograms to be made as supportive and durable as possible.

In order to meet the requirement for holograms to withstand mechanical or other effects, it has previously been suggested that a thin, durable film layer be provided on the transfer structure of the transfer tape, which acts as a protective layer for the hologram 15 after transferring to the final substrate (EP-A2466118). This provides sufficient protection of the hologram against mechanical and other loads, but transferring this layer to the substrate requires additional method steps, since the supporting protective layer does not break when moving from the edge of the activated adhesive layer, thereby preventing the element from being removed. Thus, it is necessary to pre-stamp the structure of the desired surface plate on the protective film prior to attaching the hologram so that the hologram can be removed from the surrounding material during transfer.

*: Alternative way to transfer relatively durable hologram labels:. for transmission by means of a documented transfer method is disclosed in Patent Publication .... · 25 DE-A1 41 30 896. Here the transport film is first subjected to a cold sizing layer, * *; on which the standard hologram structure is finally placed, in that order,

Tl. ' where it will later appear in the document, followed by the application of a strong protective * · · * · * * layer. To form bounded discrete elements, the sandwich structure is stamped without damaging the transport film. The extra layer (net) i '· * 30 of the layer combination is removed from the transport film so that only separate labels are left on the transport film. During transfer, the transport film is removed and the label *: affixed to the docking station using a cold sizing layer. Because the adhesive layer is. ··· [covered with a transport film, the automatic transfer of these labels is complicated • · '** and requires additional hardware components that still raise the already expensive cost of manufacturing hologram elements.

• ·

The problem of the invention is thus to provide a transfer material from durable and tear-resistant layers containing diffraction structures which, by transfer method 3118041, permit the insertion of discrete elements in a protected article in a simple and cost effective manner.

The solution to this problem is disclosed in the independent claims. Variations are disclosed in the dependent claims.

The invention is based on the basic idea that the contours of the separate movable element are already taken into account when forming the element layer structure on a substrate or transport film, i.e., the individual elements are formed directly on the transport film of the composite layer. The order of the layers therein is typical of transfer elements, whereby the adhesive layer forms the outermost layer unless it is already pre-applied to the 10 documents. However, these successive layers are placed on the conveyor belt in areas that are spaced apart.

An advantage of the inventive solution is that virtually any material can be selected for the layered structure of the individual elements, simply because they are appropriate to the element being produced. Furthermore, the transfer of the elements does not require any additional equipment or measures which would make the transfer of these elements more laborious and thus ultimately increase the price of the final product. Since the later geometric dimension of the element with the object to be protected has already been taken into account when forming the element layer structure on the carrier, it is not necessary to cut the layer structure at the edges of a hot stamping die as in the conventional punching process. Thus, of course, a specially shaped hot stamping die can also be omitted. When using hot melt adhesives, * is sufficient to ensure that sufficient heat is applied to activate the adhesive.

»» »« * • ·. . The prior art device for pre-stamping the pre-stamping layers, if any, in the elementary layer structure is also no longer required * * * *** 25 for transferring the elements according to the invention. Another advantage can be seen in the fact that it is practically not produced. With conventional hot stamping films arranged on · ·: the entire layer structure of the movable element, the elements are stamped according to the desired outline shape using a hot stamping die so that the excess is always left on the transport tray. However, according to the invention, only the amount of material needed for subsequent transfer is provided on the carrier when the elements · · · have been transferred to the document material, the carrier is virtually free of any layer material, and may be reused to form separate elements.

According to a preferred embodiment, the composite layer comprises a transport film on which reactive varnish has been applied in the form of a later 4118041 element at regions spaced apart. This lacquer layer comprises a diffraction structure in the form of an embossed embossed structure provided with a thin reflective layer, preferably a metal layer. Preferably, the application of the metallization is effected using a mask by means of chemically soluble inks. The conveyor film with these co-5 patterned lacquer areas is subsequently printed with soluble ink on the metal-free areas and subsequently metallised, for example, in a vacuum evaporation unit. The inks immediately above the metal layers are washed away in a solution bath. The metallized embossing remains on the transport film. When transported to the object to be protected, for example to the security agent or to the product package 10, the object is preferably provided with an adhesive layer, the tolerance of which is greater than that of the element to be placed on it.

In order to easily remove the layer structure of the element from the transport film, it may be provided with a crotch layer. It is preferably a cold release reaction lacquer known from DE 44 04 128.4.

Other embodiments of the invention and its advantages will be described with reference to the drawings. For the sake of clarity, the various layers of the layer structure shown in the figures are shown in intercalated thicknesses rather than on a proper scale.

Figure 1 shows a security agent with a single hologram in place.

Figure 2 illustrates a layered combination according to the invention.

Figures 3a-3f show the production of a layer combination according to the invention and a separate. . moving the element to the object to be protected.

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···. · '··· · ”" · Figure 4 shows another embodiment of the layer combination according to the invention.

*** · [Figure 5 shows the transfer of a separate element to the object to be protected.

Fig. 1 shows a banknote 1 having an optically * · • * · in accordance with the present invention. variable element 2. The optically variable element 2 is preferably a reflective hologram transmitted by a transmission method to the document 1 separately. \ element.

• · ♦ ♦ · · ... taa a * · ·

Fig. 2 shows a layer assembly 10 according to the invention comprising a substrate 3,. . ·. 30 on which the holographic discrete elements 2 are placed in areas of mutual distance. The elements disclosed herein comprise an embossed lacquer layer 6, a metal layer 5 embossing the embossed pattern, and a second lacquer layer 4 which serves as a protective layer. The protective layer likewise advantageously comprises a reaction lacquer layer.

Since the elements 2 are made as separate elements separate from the transport platform, the sandwich structure can thus consist of any other sandwich materials. For example, stable thermoplastic layers 5 may be used instead of lacquer layer 6, as disclosed, for example, in EP A2 0466118. It is also possible, for example, to use a dielectric layer having a suitably fitted refractive index instead of a metal layer 5. As a substrate 3 any material can be used which meets the desired requirements for tear strength and adhesive properties, but preferably a plastic film is used.

Referring to Figure 3, the following describes the production method and the transfer of a separate element 2 to the object to be protected. In the first step, preferably a lacquer layer 6 of a size and shape corresponding to the hologram to be applied is printed on the conveyor belt 3 at regular intervals. As schematically shown in Fig. 3a, this can be done in a screen-printing unit 15, but other overprinting and / or printing methods (for example, screen printing) may be contemplated.

The printed lacquer layer 6 may be a reaction lacquer layer, for example UV or blue light cure or UV activable lacquer, as disclosed in German Patent Application P 4404128.4, which is specifically incorporated herein by reference.

Thereafter, this printed transport film is provided with a lacquer coating 6 in the area of:: ··· 20 diffraction structure 9 by contacting the movable embossing structure 7 of the movable embossing structure 9 with the lacquer layer 6 and curing the lacquer layer 6 (Figure 3b).

• · · ·: As shown in Figure 3c, the transport film is chemically imprinted in the next step • * ·: the soluble ink 8 is applied to areas where there will be no metallization in the final layer combination. Because the lacquer layer area 6 is wider than: the actual embossed area 9, to allow for alignment tolerances, the lacquer layer 6 also has a sliding ink 8 printed on its periphery, so that substantially only the embossed structure 9 is left unpressed. The transport film 3, thus produced, is then subjected to an all-over metallization 5, which covers both the ink areas and the embossed structure 9 (Fig. 3d). The metal: ***: ringing can be done by any conventional method, for example by vacuum evaporation * * * · * ·. In the next step, the soluble ink 8 is removed so that the portion of the metal layer 5 above it is removed in a suitable solution bath. As shown in Figure 3e, the transport film 3 has only embossed varnish areas 6 and a metal layer 5 covering the embossing 9. Instead of applying the mask with a chemically sliding ink, as described above, another masking method can of course be used to metallize the embossing. .

Optionally, the metallization can now be covered by a protective layer 4 as shown in Figure 2. To transfer the elements to the object to be protected, either the object or the element area 2 of the transport film 3 is provided with an adhesive layer 11, preferably a reactive adhesive, whereby the adhesive 11 covers a larger area than the actual movable element 2, subject to possible tolerances. 2 area, and the adhesive 11 is cured. In the final step, the conveyor belt 3 is removed (Figure 3f).

The in place hologram now comprises an embossed metallized inner region, and a transparent narrow edge region overlapping the varnish layer and the adhesive layer, which, in addition to smoothing manufacturing tolerances, also seals the metal layer, protecting it from environmental damage.

In order to facilitate the removal of the elements from the transport film, the film may be subjected to a waxy separation layer, for example, an easily removable reaction lacquer layer, before being coated on islands such as islands.

Because the counterfeit papers have a relatively rough surface to receive the watermark, and since this roughness may: Y: interfere with the visual impression of the diffraction structures, it is often advantageous to smooth the area of the paper where the security element is to be set.

This can be done by squeezing the paper and / or applying a softening primer.

In the variation of the above-described embodiment, additional optical effects can be obtained by providing the embossed area with or without printing the lacquer layer ·· *: V 6 without printing with ink 8 (see Figure 3). Further, when letters, patterns or the like are printed on the embossed area, a metal-free area can be obtained in the embossing 9 of the hologram, which represents, for example, readable information.

* · * * | ; The application of the method described is, of course, not limited to the transfer of holograms to Γ '* banknotes. Interference layer elements or other layer structures which have optical effects depending on the viewing angle may also be positioned in the vehicle. and transfer it to some protected item, such as the product packaging, * · · * *! the actual products, or ID cards, in the same way as described above for holograms.

However, the inventive method can also be advantageously used in connection with conventional thermoplastic hologram layers since they no longer need to be cut off, but can be as stable as possible. In this case, for example, the transport film 3 is pressed in the first step, for example, a waxy separation layer 16 over the entire tape, or similarly, at the separately positioned locations. The transport film is then imprinted with a thermoplastic lacquer 17, as shown in Figure 3a. The following production steps proceed in the same manner as shown in Figures 3b-3e. In the final step, the adhesive layer is applied to the elemental layer structure, whereby this layer should be somewhat larger than the embossed lacquer layer 17 to compensate for tolerances and to close the metal layer. Fig. 4 shows the structure of layers 20. The adhesive layer 18 may be either of the aforementioned varnish or hot melt adhesive.

The individual elements 2 produced in this manner are displaced by a heated die 19 which activates the hot melt adhesive 18 and secures the element layer structure 2 to the substrate 1 (Figure 5). Finally, in the final step, the transport film 3 is removed.

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Claims (19)

118041 Transfer material (10, 20) for transferring optically variable elements (2) from the carrier (3) to objects to be protected (1), in particular to value holders such as banknotes or ID cards, wherein the elements (2) on the carrier (3) 5 are separate as individual elements and the transfer material comprises a plurality of layers in the region of the elements: - a transport base (3), - optionally a separation layer (16), - a layer (6.17) having diffraction patterns (9) in the form of embossed 10 and outline of the movable element (2), - a reflective layer (5) imaged only in the inner region of the layer (6, 17), wherein the diffraction structures are located such that the narrow peripheral region of the layer (6, 17) is free from the reflective layer. Transfer material according to claim 1, characterized in that the diffraction structures (9) occur in the inner region of the layer (6, 17). Transfer material according to claim 1 or 2, characterized in that: V: in the region of the elements (2) on the surface of the transfer material (10, 20) away from the transport material (10) there is an additional layer (4, 18) which (6, 17) on top of the narrow free reflective layer on top j, thus closing the reflective layer (5). Transfer material according to claim 3, characterized in that the additional layer is an adhesive layer (18). ··. 25 Transfer material according to one of Claims 1 to 4, characterized in that the reflective layer (5) is a metal layer. • ♦ Transfer material according to any one of claims 1 to 5,. characterized in that the layer (6, 17) with diffraction structures is a * · * · * reaction lacquer or thermoplastic layer. • ** · * · · * · ·: 30 Transfer material according to claim 4, characterized in that the adhesive layer (18) has larger dimensions than the layer (6, 17) provided with diffraction structures 9 118041, but the adhesive layer does not completely cover the transport substrate (3). Transfer material according to at least one of the preceding claims 4 and 7, characterized in that the adhesive layer (18) is a reaction adhesive or a hot melt adhesive. Transfer material according to one of Claims 1 to 8, characterized in that the reflective layer (5) has openings in the form of kernels or patterns. Transfer material according to one of Claims 1 to 9, characterized in that the layer combination has a waxy separation layer (16) between the carrier (3) and the layer (6, 17) with diffraction structures. A method of producing the transfer material of claim 1 for transferring optically variable elements to protected items, in particular documents of value, such as banknotes or ID cards, characterized by the steps of: a) providing a carrier; b) partially coating, in portions, the surface of the transport platform with a layer on which embossing can be formed, said layer having the outline of movable elements 20; . c) adding diffraction structures to the embossed layer; ** \ d) forming a mask for those areas of the transport substrate that do not have a · · *: ♦ embossed layer and a narrow peripheral area of the • · «: .i ί layer containing diffraction structures; 25 e) adding a reflective layer; • · · (f) removing the mask and the reflective layer on top of the mask. ♦ ·· • · · * · · - 12. Förfarande enligt krav 11, kännetecknat av att maskeringen sker medelst chemiskt lösliga tryckfärger. A method according to claim 11, characterized in that the mask is formed using chemically soluble inks. • ·· * 13. Förfarande enligt krav 11, kännetecknat av att det det refekterande skiktet et metallskikt. 15 14. Förfarande enligt ett av kraven 11-13, kännetecknat av att bärsubstratet är en plastfolie. The method according to claim 11, characterized in that the reflective layer 30 is a metal layer. • · * • · • * ··· A method according to any one of claims 11 to 13,. . ·. characterized in that the carrier is a plastic film. The process according to claim 14, characterized by the following steps: printing a chemically soluble ink in areas of the plastic film which will not be metallized in step d); h) metalizing the entire printed surface of the plastic film in step e); i) removing the soluble ink and the metallization on top thereof in step 5 f) so that the metallization remains only in the ink-free areas of the plastic film. 15. Förfarande enligt krav 14, kännetecknat av feljande steg:: V: g) i steg d) tryckning av de omräden som skall metal seras med en ····· chemiskt löslig tryckfärg; • · • · f j 20 h) i steg e) metal insulating cavity hela ytan av plastfoliens tryckta yta; : i) i steg f) avlösning av den lösliga tryckfärgen och den där over * · · ·; * · *. liggande metal ring save the metal ring itself as quarblir i de förut tryckfärgfria omräd. • ”16. Förfarande enligt krav 15, kännetecknat av att metal ringen i steg h) ··· 25 sker efter vacuumängförfarandet. ·· »· · Process according to Claim 15, characterized in that the metallization of step h) is carried out by vacuum evaporation. 17. Förfarande enligt minst ett av kraven 11-16, kännetecknat av att * · * ··· 'bärsubstratet före steg b) ätminstone partiellt trycks med ett vaxartat: separationsskikt. • · · * ♦ • * »• 18. Förfarande enligt minst ett av kraven 11-17, kännetecknat av att i steg b) 30 ett reactionslack eller ett thermoplastiskt lack pätryckes. 13 1 1 8041 Method according to one of the preceding claims 11 to 16, characterized in that, before step b), the waxy separation layer is pressed onto the carrier at least partially. Process according to one of the preceding claims 11 to 17, characterized in that, in step b), the reaction lacquer or thermoplastic lacquer is printed. Method according to one of the preceding claims 11 to 18, characterized in that openings in the form of letters or patterns are made in the reflective layer. 1. · Ö · · · · 20 1. Överföringsmaterial (10,20) för överföring av optiskt variabla element (2) ··· ♦ · / / frän et bärsubstrat (3) end object (1) som skall skyddas, shimmer color paper, ♦ · ♦ j säsom sedlar eller idetetskort, color elementsen (2) foreligger pä bärsubstratet (3) som frän varandra ätskilda Enskilda element och • ·: överföringsmaterialet i omrädet för elementen uppvisar feljande skiktföltd: 3), ··: * ·· - eventuellt ett separationsskikt (16), · · · • ♦ * · - ett skikt (6, 17), i flash brytningsstrukturen (9) i form av en relief är (införd och skiktet ( 6, 17) uppvisar konturformen av ett element (2) • ♦ · som skall överföras, • · · * “*! 30 - that the reflector (5), the self-foreligger i det inre omrädet av • * · '· "det brytningsstrukturen uppvisande skiktet (6, 17), so the skel (6, 17) is a foreligger that smelt reflexionskritfritt. 1 8041 2. Överforingsmaterial enligt krav 1, kännetecknat av att brytningsstrukturen (9) föreligger i et inre omräde av skiktet (6,17) 3. Överforingsmaterial enligt krav 1 eller 2, kännetecknat av att i omrädet för 5 elements (2) den frän bärsubstratet (3) crank ytan av överföringsmaterialet (10, 20), and anordnat et ytterligare skikt (4, 18), som ververlappar med den smala reflexionsskiktfria kanten av detringeringsstrukturen uppvisande skiktet (6, 17) och diktens 4.) Överforingsmaterial enligt krav 3, kännetecknat av att det ytterligare skiktet 10, pre limskik (18) 5. Överforingsmaterial enligt krav 3 1-4, kanknetecknat av att det det refekterande skiktet (5) ä 6. Överforingsmaterial enligt omit the opening of the crane 1-5, the bending nozzle of the braking system (6, 17) and the reaction slacks of the thermoplastic. 7. The overlapping material enligt krav 4, the tiling pattern (18) and the dimensioning pattern of the bracing structure (6, 17), the docking element (3) overlapping. 8. The overwintering material is then removed from the crane 4 eller 7, the turning deck is att '\ 20 lime pad (18) and the reaction eller is assured. • ·: 9. Överforingsmaterial enligt minst ett av kraven 1-8, kännetecknat av att det ♦; ··: refekterande skiktet (5) uppvisar ursparingar i form av tecken eller mönster. • ♦ • · ♦ · * ;; / 10. Överforingsmaterial enligt minst ett av kraven 1-9, kännetecknat av att det • · φ * · '* samansatta skiktet mellan bärsubstrat (3) och det brytningsstrukturen 25 uppvisande skiktet (6, 17) ) uppvisar ett vaxartat separationsskikt (16). ·· • · »··. ***. 11. Förfarande för tillverkning av etververingsmaterial enligt krav 1 för * «* överföring av optiskt variabla element pä object som skall skyddas, särskilt · · ·: ·· *. (a) tillhandahällande av ett bärsubstrat; • «· '9. (B) lot, avsnittsvis beläggning av en yta av bärsubstratet med et präglingsbart skikt, colors are sketched on the main contour of the element som skall överföras; (c) införande av brytningsstrukturen i det präglingsbara skiktet; (D) maskering av bärsubstratet i de omräden, i försetts med brytningsstrukturen; (e) headland av det reflekterande skiktet; (f) 10 reflekterande skiktet. 19. Förfarande enligt mind to open the kraven 11-18, kännetecknat av attit det refekterande skiktet ursparingar i form av tecken eller mönster äcomkom. • · • · 9 • · * 1 • · • ♦ «• · · * 1 · • • • • • • • • • •••••••••••••••••••••• • · • 1 # • · · ♦ · • 1 · 1 ·• 1 · · · 1 · • · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · call ··