RU2759482C1 - Multilayer protective optical diffraction device, a method for manufacturing the specified device, a protected product containing the specified multilayer protective optical diffraction device - Google Patents

Abstract

FIELD: counterfeit protection.SUBSTANCE: group of inventions relates to protection against forgery of valuable documents, in particular to a method for manufacturing a multilayer protective optical diffraction device and to a protective device made according to the specified method, as well as to a protected product and a valuable document, each containing the specified protective device. A multilayer protective optical diffraction device contains at least two information-bearing elements; in this case, the first information-bearing element is made in the form of at least one diffraction grating and/or at least one relief hologram with a predetermined first picture distribution of stroke directions, depth and stroke periods in these diffraction gratings and/or relief holograms and with the provision of microcracks located along the strokes over the entire area occupied by these diffraction gratings and/or relief holograms; the second information-bearing element is made in the form of at least one relief hologram of the wallpaper type with a predetermined second picture distribution of stroke directions, depth and stroke periods in these relief holograms of the wallpaper type, while the design of at least one diffraction grating and/or relief hologram with a predetermined first picture distribution of stroke directions, the depth and periods of strokes in the specified diffraction gratings and/or relief holograms of the first information-bearing element differs from the design of at least one relief hologram of the wallpaper type with a predetermined second picture distribution of the directions of strokes, depth and periods of strokes in the specified relief hologram of the second information-bearing element.EFFECT: expansion of the range of optical instruments.30 cl, 2 dwg

Description

Technology area

The invention relates to the field of protection against counterfeiting and verification of the authenticity of valuable documents, in particular to a multilayer optical diffractive security device for protecting valuable documents and to a method for manufacturing said security element exhibiting diffraction effects.

State of the art

Initially, diffraction and polarization-interference effects were widely used for advertising, information and entertainment purposes and in visual products, but with the development of technology in the field of technology, they have recently been widely used as security elements or devices for protecting against forgery and verifying the authenticity of valuable documents. such as securities, banknotes, checks, credit cards and stamps and the like.

Many different technical solutions are known from the prior art, using diffractive structures or holograms as basic components of a security element.

In the present description, the term "hologram" or "diffractive structure" are used interchangeably

In particular, from RU2480550C1, publ. 04/27/2013 IPC D21H21 / 48 known a combined security element containing a multilayer structure, in different layers of which are formed visually distinguishable, conjugate images, and one or more images are made in the form of holographic gratings placed in different layers of the multilayer structure, as well as printed images and images obtained by high-precision demetallization or embossing and a method for manufacturing the specified combined security element, including obtaining a multilayer polymer structure, applying lacquer, ink and photoresist masks to this structure by means of printing technologies and forming on the basis of masks conjugated holographic, printed, embossed and etched images, while the application of these masks and the formation of conjugated images is carried out in one technological cycle using a holographic relief as marks for optical register, and the areas covered by masks are located They are located inside areas with a holographic relief, and the distance between the boundaries of the areas covered by masks and the boundaries of areas with a holographic relief is 50-100 μm (see. page 5, lines 23-27 of patent RU 2480550). The disadvantage of the known method of manufacturing the specified element is the specified limitation in the accuracy of registering holographic and printed images, which makes it impossible to create complex holographic printed images with an accuracy of registering to each other less than 50-100 microns, especially in the mass production of such security elements.

Patent RU 2 677 967C2, publ. 22.01.2019, IPC B42D25.355 discloses a double-sided security element having transparent and opaque areas. In this case, on the one hand, the opaque areas represent a metallized layer, while on the other side, the areas located opposite the former can be color-changing, changing color when the angle of view changes, or covered with photoresist masks, magnetic pigments, or fluorescent ink. At the same time, transparent and opaque areas can be the same in shape and relative position. The method of manufacturing such an element consists in sequential demetallization of the first metal layer by means of partial masking with a resistive protective layer and subsequent chemical etching of open areas of the metal layer, applying a color-variable and photoresist layer on the reverse side of the film, exposing the photoresist layer from the side of the partially demetallized layer and subsequent chemical etching.

The disadvantage of the proposed double-sided security element is the use as a basis for its placement on two sides of a commercially available anisotropic birefringent (DLP) film from the polyethylene terephthalate (PET) class, on both sides of which images are formed in the form of transparent and opaque areas, with a thickness ranging from 10 and above microns: 1) the presence of DLP impairs the color-changing protective properties of layer 4, made, for example, of an LC material, both of layer 4 itself, and of the protective properties of ZE as a whole; 2) the high thickness of industrially produced oriented PET films does not allow obtaining images in the form of demetallized and / or holographic regions of micron (less than 5 microns) topological dimensions using the polygraphic method of obtaining masks for demetallization of regions.

The closest technical solution to the claimed invention is a security element with an image and a double-sided holographic effect, disclosed in patent RU 2 685 791C2, publ. 04/23/2019, IPC B42D25 / 328, the specified security element contains a transparent first layer with a holographic surface structure, the first metal layer located on the specified first layer in the form of a first diffraction image, thus forming transparent and opaque areas and a holographic surface structure, the second layer located on said first metal layer and having a second holographic surface structure, a second layer located on said first metal layer and having a second holographic surface structure and a second metal layer located on said second layer in the form of a second image, thus forming transparent and opaque areas and holographic surface structure. In this case, said transparent regions of the first metal layer and the second metal layer are arranged so that the transparent and opaque regions of these layers coincide, so that when viewed in transmitted light from one side and when viewed in transmitted light from the other side, the security element reveals an image on one side and its mirror image on the other side, respectively. The holographic surface structure of the first metal layer is different from the holographic surface structure of the second metal layer, so that the security element exhibits a first holographic effect in opaque regions when viewed from one side in reflected light and exhibits a second holographic effect in opaque regions different from the first holographic effect when viewed from the other side in reflected light.

The disadvantage of the closest analogue as a security element with a transparent image in the form of a transparent light-transmitting stencil and bilaterally reflecting diffraction images based on holographic effects, declared in patent RU 2 685 791C2, is the complexity of high-precision topological spatial alignment of at least one picture-demetallized transparent region and at least at least one specularly reflecting area with picture holographic gratings, placed in pairs on each of the two sides of this element in a single microdemetallization stencil. In the technology of its manufacture, this combination is carried out in RU 2 685 791C2 using a resistive mask in the form of an image, resistant to demetallization of the layer underlying it. The mask is obtained by the method of local printing on one side of the metallized layer during the formation of the first picture metallized layer with register accuracy of the order of 50-100 microns of both metallized and demetallized areas on this side and then on both sides of the security element.

In addition, the disadvantage of the proposed technology for manufacturing a security element using a resistive mask in the form of an image is a possible discrepancy between the topologies of transparent and opaque areas of both information-bearing layers, which degrades the quality of the security features stored in them. Another disadvantage of the specified security element, disclosed in RU 2 685 791C2, is the limited functionality of only visible to the naked eye protective features, which significantly limits its degree of protection against unauthorized access.

The objective of the claimed solution is to eliminate the disadvantages of the above information sources and create an optical diffractive protective optical means, i.e. a security device with several levels of protection against counterfeiting, which is at the same time evidence of the authenticity of the protected object.

At present, for protection against counterfeiting and as signs of authenticity of protected objects, special security means and signs of identification of authenticity are used (in addition to various means of printing security), built into the protected product in the form of a transparent or translucent polymer window carrying one or more security features, such as various visible images, color-changing effect in transmitted and reflected light, diffraction, holographic and other optical effects. Among security elements with variable optical properties, the most difficult to reproduce are those containing several security features of different physical nature.

Thus, the authors of the invention have created a multilayer protective optical diffractive device with significantly improved protective properties, which are provided by the formation of various diffractive structures, including diffraction gratings and holograms on both sides of the proposed multilayer security device with an almost ideal spatial accuracy of relative position up to 5 μm, as a result of imparting one of at least two metal layers with diffractive structures located on it, a property that prevents the effect of its demetallization at their locations and the formation of demetallized transparent regions of the other of at least two metal layers using a layer of positive photoresist.

The essence of the invention

According to a first aspect of the invention, there is provided a method for manufacturing a multilayer protective optical diffractive device, comprising the steps of:

1) provide a carrier film;

2) a separating layer is applied on one side of the carrier film;

3) the first thermoplastic transparent isotropic polymer layer is evenly applied to the separating layer;

4) evenly applying the first metal layer on the specified first thermoplastic transparent isotropic polymer layer;

5) by hot embossing, at the same time, on the surface of the first thermoplastic transparent isotropic polymer layer and the first metal layer, a first information-bearing element is formed containing at least one opaque metallized diffractive region and at least one transparent region;

5a) in this case, the formation of the first information-bearing element contains the stages at which:

5a1) provide relief microstructuring of the surface of the first thermoplastic transparent isotropic polymer layer with the first metal layer applied to it with the formation of diffraction structures containing at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the stroke directions, with predetermined depth and period of grooves in said diffraction gratings and / or relief holograms and providing microcracks located along the grooves over the entire area occupied by said diffraction gratings and / or relief holograms;

5a12) while the diffraction structures of the first thermoplastic transparent isotropic polymer layer formed in step 5a1) completely repeat the diffraction structures of the first metal layer;

5a2), a layer of a liquid composition with reactive additives is applied to the first metal layer with embossed diffractive structures to ensure the process of diffusion of the specified liquid composition through microcracks into the first thermoplastic transparent isotropic polymer layer, providing it with an intermolecularly cross-linked three-dimensional structure and ensuring resistance to demetallization areas of the first metal layer with embossed diffractive structures;

5a3) provide the etching of the first metal layer to ensure demetallization in areas where there are no diffractive structures;

- the second thermoplastic transparent isotropic polymer layer is evenly applied to the first metal layer;

6) evenly applying the second metal layer to the second thermoplastic transparent isotropic polymer layer;

6a) by hot stamping, at the same time, on the surface of the second thermoplastic transparent isotropic polymer layer and the second metal layer, a second information-bearing element is formed, comprising at least one opaque metallized diffractive region and at least one transparent region;

in this case, the formation of the second information-bearing element contains the stages at which:

6a1) provide a relief microstructuring of the surface of the second thermoplastic transparent isotropic polymer layer with a second metal layer applied to it in the form of diffraction structures containing at least one relief hologram with a predetermined second picture distribution of strokes directions, with a predetermined depth and period of strokes in said relief holograms.

6a12) at the same time, formed in step 6a1) at least one embossed hologram of the second thermoplastic transparent isotropic polymer layer completely repeats at least one embossed hologram of the second metal layer;

- in this case, the design of at least one diffraction grating and / or relief hologram with a predetermined first picture distribution of groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information-bearing element differs from the design of at least one relief hologram holograms with a predetermined second picture distribution of stroke directions, depth and periods of strokes in said relief hologram of the second information carrier.

7) a layer of positive photoresist is evenly applied to the second metal layer over the entire area of the security device;

8) uniformly exposing a layer of positive photoresist applied to the second metal layer with UV radiation directed from the side of the first metal layer through demetallized portions of said first metal layer, functioning as a transparent photomask;

9) removing the exposed areas of the positive photoresist layer in the areas of the second metal layer corresponding to the demetallized areas of the first metal layer, through which exposure to UV radiation was carried out;

demetallizing the second metal layer at the remote exposed areas of the positive photoresist layer to form demetallized transparent areas;

10) a homogeneous optically transparent layer is applied over the second metal layer and over the entire surface of the security device on one side, while the said layer completely repeats the relief structure of the second metal layer;

- apply a varnish coating over a uniform optically transparent layer, over the entire surface of the optical protective device.

In this case, the carrier film is made of polyethylene terephthalate (PET) or polypropylene (PP) and has a thickness in the range from 12 microns to 100 microns.

A separating layer is made of synthetic wax compositions and has a thickness in the range of 0.2-0.5 microns or is made of an adhesive composition and has a thickness in the range of 3-5 microns.

In this case, the application of the first thermoplastic transparent isotropic polymer layer on the separating layer is carried out by the printing method, which is one of: gravure printing method, offset or flexographic printing method.

In addition, the first thermoplastic transparent isotropic polymer layer is made of linear macromolecules of at least one of polyurethane acrylate, epoxy acrylate, aryl acrylate or acrylate, phenol-formaldehyde resin or combinations thereof, while the first thermoplastic transparent isotropic polymer layer has a thickness in the range from 0.7 to 1.0 μm.

And the first metal layer is made of at least one of: aluminum, copper, brass, bronze, steel, zinc, tin, or their alloys and has a thickness in the range from 10-20 nm, and also has an optical transmission of 10% in the UV region spectrum.

In this case, the first information-bearing element and the second information-bearing elements consist of an opaque metallized diffractive region and a transparent region in the form of a flat demetallized region made of a layer of thermoplastic polymer material.

In this case, the relief microstructuring of the first thermoplastic transparent isotropic polymer layer is performed in such a way that the formed diffraction structures have a picture angular and spatial distribution of grooves in the range from 0 to 179 degrees, while the picture value of the spatial frequency of grooves in the region of the location of holographic images changes according to a given law within 200-2000 lines / mm with a groove depth within 20-400 nm and a given shape of their profile within these grooves, and formed at the stage of the first relief microstructuring of the first thermoplastic transparent isotropic polymer layer, diffraction structures form pictures with different designs, depending on from the manufacturer's requirements.

It should be noted that the layer of the liquid composition with reactive additives applied to the first metal layer at step 5a2) is a liquid composition based on photoinitiators of radical polymerization such as 2,2-dimethoxy-2-phenylacetophenone (Irgacure-651) with reactive additives in the form of active diluents such as isobornyl acrylate or.

the layer of the liquid composition with chemical-active additives applied to the first metal layer in step 5a2) is a liquid composition based on photoinitiators containing a benzoyl group with substituents with a radical cationic cation mechanism, containing tanning agents, such as benzophenone and its alkyl derivatives.

In this case, the etching step 5a3) is carried out by placing the carrier film with the first thermoplastic transparent isotropic polymer layer and the first metal layer deposited in a solvent based on acetic and nitric acids.

In addition, the second thermoplastic transparent isotropic polymer layer is made of linear macromolecules of at least one of polyurethane acrylate, epoxy acrylate, aryl acrylate, acrylate, phenol-formaldehyde resin, or combinations thereof, and has a thickness of about 1.5 μm.

In this case, the second metal layer is made of at least one of: aluminum, copper, brass, bronze, steel, zinc, tin, precious metals or their alloys and has a thickness of about 1.5 microns.

In addition, at the stage of performing relief microstructuring of the second thermoplastic transparent isotropic polymer layer, the formed relief holograms are holograms with non-positioned patterns, such as wallpaper holograms.

It should be noted that at the stage of performing the relief microstructuring of the second thermoplastic transparent isotropic polymer layer, the formed wallpaper holograms have a picture angular and spatial distribution of strokes in the range from 0 to 179 degrees, while the picture value of the spatial frequency of strokes in the region of the location of holographic images in relief holograms changes according to a given law within 200-2000 lines / mm with a groove depth within 20-400 nm and a given shape of their profile within these grooves.

At the same time, formed at the stage of relief microstructuring of the second thermoplastic transparent isotropic polymer layer, wallpaper holograms form pictures with different designs, depending on the manufacturer's requirements.

It should be noted that they provide the stage of relief microstructuring of the surface of the first thermoplastic transparent isotropic polymer layer at step 5a1) by means of a nickel matrix-hologram with the first predetermined relief structuring of the surface and the stage of relief microstructuring of the surface of the second thermoplastic transparent isotropic polymer layer at step 6a1) by means of a nickel matrix - holograms with a second predetermined surface relief structuring, wherein the relief structuring of the surface of the first thermoplastic transparent isotropic polymer layer differs from the second surface structuring of the second thermoplastic transparent isotropic polymer layer.

In addition, the step of applying a layer of positive photoresist to the second metal layer is carried out by a printing method that is a gravure, letterpress offset printing or flexographic printing method, and the positive photoresist layer has a thickness in the range from 0.8 μm to 1.0 μm.

And the step of removing the exposed areas of the positive photoresist layer in the specified areas of the second metal layer is carried out by washing off the specified exposed areas of the photoresist layer using an alkaline developer based on, for example, 1.0-5.0% aqueous solution of tetramethylammonium hydroxide or trimethyl (2-hydroxyethyl) ammonium hydroxide with a fluorinated surfactant.

In this case, the homogeneous optically transparent layer is made of cured linear macromolecules of one of: polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins, and the homogeneous optically transparent layer and the first and second thermoplastic transparent isotropic polymer layers have essentially the same refractive index.

According to a second aspect of the invention, there is provided a multilayer protective, optical diffractive device made in accordance with the method according to the first aspect of the invention and comprising a carrier film and applied thereto: at least two thermoplastic transparent isotropic polymer layers, at least two metal layers, and

homogeneous solid-state optically transparent layer;

and also a lacquer coating over the entire surface of the optical security device;

wherein at least two thermoplastic transparent isotropic polymer layers and at least two metal layers are made in such a way that the formation of at least two information-bearing elements is ensured;

wherein the first information-bearing element is made in the form of at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the groove directions, the depth and periods of the grooves of said diffraction gratings and / or relief holograms and providing microcracks located along the lines over the entire area occupied by the indicated diffraction gratings and / or relief holograms;

the second information-bearing element is made in the form of at least one embossed hologram with a predetermined second picture distribution of the directions of the strokes, the depth and periods of the strokes in the said embossed wallpaper-type holograms,

in this case, the design of at least one diffraction grating and / or relief hologram with a predetermined first picture distribution of groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information-bearing element differs from the design of at least one relief hologram wallpaper type with a predetermined second picture distribution of stroke directions, depth and periods of strokes in said embossed hologram of the second information carrier.

According to another aspect of the invention, there is provided a security article comprising applied or embedded therein a multilayer security optical diffractive device that can be used as a transparent window in at least a portion of the security article. In this case, the protected product is

valuable documents including securities, banknotes, checks, credit cards, stamps.

According to a further aspect of the invention, there is provided a document of value comprising a multilayer security optical diffractive device according to the invention used as a transparent window in at least a portion of the document of value.

In this case, the valuable document is securities, banknotes, checks, credit cards, stamps.

Description of drawings

The features, elements and advantages of the invention follow from the following description of an embodiment of the invention with reference to the accompanying drawings, which show:

Fig. 1 is a schematic top view from one side of a security article with a multilayer security optical diffractive device placed thereon;

Fig. 2 is a schematic view of the structure in cross-section along the line A-A of the multilayer protective optical diffractive device according to Fig. 1, which is a bilaterally demetallized light-transmitting portion A-A, located between two metallized diffraction-grating fragments of a multilayer protective optical diffractive device according to the present invention.

DESCRIPTION OF THE PREFERRED IMPLEMENTATION

THE INVENTION

In order to eliminate the drawbacks of the known technical solutions known from the prior art, the inventors, in which the manufacturing process does not sufficiently ensure high-precision topological spatial alignment of the demetallized transparent region and the specularly reflecting region with diffractive structures, i.e. a possible discrepancy between the topologies of transparent and opaque areas of information-bearing layers, which deteriorates the quality of the security features stored in them, the method of high-precision demetallization (HPMO) was used with a spatial resolution within 5 microns between the “metallized-demetallized” areas, and Also, to obtain a high-precision copy of the demetallized region of one of the optical elements of the security device, a metallized holographic region of another optical element of the security device was used as a photocopying mask, which

provides compatibility of boundaries between "metallized-demetallized" areas of the order of 1-2 microns. Further, the authors consider it necessary to present some of the features of the processes occurring in the manufacture of the claimed security device for a more detailed disclosure of the advantages of the method of manufacturing a security device proposed by the authors of the present invention.

In the manufacture of a protective device using the method of high-precision microdemetallization with a spatial resolution within 5 microns between the "metallized -demetallized" areas, as thermoplastic transparent isotropic layers, on the surface of which by the hot stamping method, relief-bearing structures with holographic graphic gratings are used, polymer materials are used based on linear macromolecules with functional active groups in the main or side chain, initially soluble in certain solvents. Such polymers can be polyurethane acrylates, epoxy acrylates, acryl acrylates, polyether acrylates, polyamides, phenol-formaldehyde, melamine-formaldehyde resins, etc.

However, they lose this property as a result of the formation of a single three-dimensional network structure when interacting, as a rule, with external chemically active substances that exhibit various physicochemical reactions such as three-dimensional condensation or, for example, physical action such as UV radiation, which forms free radicals inside macromolecules, leading to the emergence of cross-links and the formation of a mesh structure;

According to the claimed invention, such a high-precision microdemetallization in space with a resolution of about 5 microns appears possible due to the fact that in the process of hot embossing of holograms in a thermoplastic layer with an initially uniform metal layer applied to it, the latter locally changes its thickness in accordance with the periodic microrelief due to the occurrence of mechanical stresses in it.

The authors of the invention found that under the hot stamping modes and the composition of the material of the metal layer in the embossed areas of this layer, nano- and microcracks are formed, located along the lines over the entire area occupied by the picture diffraction gratings of the security element up to their geometric border of the order of several microns, depending on from the lattice period in the border area. The authors carried out research and identified the modes of the hot stamping process for the formation of microcracks in the metal layer, which consists in using a nickel matrix (matrix-hologram) at an embossing temperature in the range of 90-130 ° C and a pressure in the range of 3.5-4.5 kg / cm ² .

When applied to such an embossed hologram with microcracks a layer of a liquid composition with reactive additives through these microcracks they diffuse into the volume of the polymeric relief-bearing layer.

This ensures the insolubility of not only the crosslinked polymer layer with a holographic microrelief, but also resistance to chemical etching of the metal layer itself, which is sewn on this crosslinked polymer layer. This is due to the mutual penetration of the crosslinked polymer structures into the metal layer. In this case, the border area between the metallized and demetallized areas is about 5 microns.

At the same time, in the mirror-reflecting areas of the metal layer without microrelief, there is no such penetration of molecules of cross-linking agents, which allows high-precision microdemetallization of these areas and subsequent removal, if necessary, of the thermoplastic transparent layer using a solvent.

All this makes it possible to obtain security elements with a spatial alignment resolution better than 5 microns.

In the proposed application, in order to obtain a high-precision copy of a demetallized region of one of the optical elements of the security device, it is proposed to use a metallized holographic region of another optical element of the security device as a photocopying mask.

At the same time, since the gap between is practically absent (as in conventional photolithographic technology, it does not exceed 1-2 microns), this ensures the compatibility of the boundaries between the "metallized-demetallized" regions of the order of 1-2 microns.

A description of the optical security device will now be presented with reference to FIG. 1 and 2.

Figure 1 presents a schematic top view from one, for example the first, side of a multilayer double-sided security article, for example a value document 10 in the form of a banknote, bank or credit card, payment document, or other official or unofficial document, etc., which has a carrier film 11 and a multilayer protective optical diffractive device 12 located in the transparent area 13 of the carrier film 11 of the valuable document 10. The transparent area 13 can be, for example, a transparent window 13, coinciding in geometric shape and location along the border with the optical protective device 12 ...

In this case, the multilayer protective optical diffractive device 12 includes at least two information-carrying optical elements, both located on each side of the optical security device 12, while the first information-carrying element is at least one opaque metallized diffractive region 14 ₁ and at least one transparent region 15 ₁ , and the second information-bearing element is at least one opaque metallized diffractive region 14 ₂ and at least one transparent region 15 ₂ . In this case, the opaque metallized diffraction regions 14 ₁ , 14 _{2 are} made in such a way that the formation of a single holographic image and / or plot independent and / or dependent on each other holographic images on each side of the multilayer protective optical diffraction device 12 is ensured.

In this case, these opaque metallized diffraction regions 14 ₁ , 14 ₂ are mirrored on each side of the optical security device 12 and have one geometric shape in one location. Each of the two opaque metallized diffraction regions 14 ₁ , 14 ₂ is a relief-structured multilayer structure consisting of relief-structured thermoplastic transparent isotropic polymer layers with a thickness of 0.7 to 1 μm, applied to each of them with a corresponding metal layer with identical relief-structured topology. In this case, thermoplastic transparent isotropic polymer layers are made of linear macromolecules of at least one of: polyurethane acrylate, epoxy acrylate, aryl acrylate or acrylate, phenol-formaldehyde resin, or combinations thereof.

And the metal layers are made from at least one of: aluminum, copper, brass, bronze, steel, zinc, tin, or their alloys. In this case, the thickness of these layers can be in the range from 10-20 nm. In this case, the composition and thickness of these metal layers are selected in such a way that optical transmission of 10% in the UV region of the spectrum is provided for each of the metal layers.

In this case, the surfaces of the opaque metal diffraction regions 14 ₁ , 14 _{2 are} made relief-structured. In this case, the opaque metal diffraction regions 14 _{1 are} structured in the form of diffraction structures containing at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the groove directions, the depth and periods of the grooves of the said diffraction gratings and / or relief holograms and providing microcracks located along the grooves over the entire area occupied by the indicated diffraction gratings and / or relief holograms.

These diffraction structures can have a picture angular and spatial distribution of grooves in the range from 0 to 179 degrees, while the picture value of the spatial frequency of grooves in the region of the location of holographic images according to a given law varies within 200-2000 lines / mm with a groove depth within 20- 400 nm and a given shape of their profile within these grooves.

In this case, opaque metal diffraction regions 14 _{2 are} structured in the form of diffractive structures containing at least one relief hologram with non-positioned patterns such as wallpaper holograms, with a predetermined second picture distribution of the direction of the strokes, the depth and periods of strokes in the said relief holograms. In this case, these holograms in the form of wallpaper-type relief holograms can have a picture angular and spatial distribution of strokes in the range from 0 to 179 degrees, while the picture value of the spatial frequency of strokes in the region of the location of holographic images in relief holograms can vary according to a given law within 200 - 2000 lines / mm with a groove depth within 20-400 nm and a given shape of their profile within these grooves.

In this case, the first and second information-bearing elements formed on one side of the security device have a different design, i.e. the design of at least one diffraction grating and / or relief hologram with a predetermined first picture distribution of the groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information-bearing element differs from the design of at least one relief hologram with a preliminary the given second picture distribution of the stroke directions, the depth and periods of the strokes in the specified relief hologram of the second information-bearing element.

In this case, the transparent regions 15 ₁ , 15 ₂ are flat demetallized regions made of a layer of thermoplastic polymer material. In this case, on each side of the optical security device 12, the area S ₂ occupied by the indicated transparent regions 15 ₁ , 15 ₂ is equal to the difference between the total area S occupied by one side of the security device 12 and the area S ₁ occupied by the opaque metallized diffractive region 14 ₁ , 14 ₂ i.e. on each side of the multilayer protective optical diffraction device 12, the following relationship will be satisfied:

S ₂ = SS ₁ .

FIG. 2 is a schematic cross-sectional view of the structure along the line A-A of a multilayer protective optical diffractive device 12 (hereinafter referred to as a security device) according to FIG. 1, which is a bilaterally demetallized light-transmitting portion A-A of transparent regions 15 ₁ , 15 ₂ , placed between the opaque metallized diffractive regions 14 ₁ , 14 _{2 of the} multilayer protective optical diffraction device 12 according to the present invention.

In this case, shown in figure 2, the first thermoplastic transparent isotropic polymer layer 23 and the first metal layer 24 provide the formation of the first information-bearing element, consisting of regions (14 ₁ +15 ₁ ) (see figure 1), and the second thermoplastic transparent isotropic polymer layer 25 and the second metal layers 26, provide the formation of the second information-bearing element, consisting of regions (14 ₂ +15 ₂ ) (see figure 1).

On the carrier, for example polyethylene terephthalate (PET) film - carrier 21 with a thickness ranging from 12-100 microns, through the separating layer 22 directly in contact with the carrier film 21, there is a first thermoplastic transparent isotropic polymer layer 23 with a thickness of about 0.7-1 microns, made of linear macromolecules of at least one of: polyurethane acrylate, epoxy acrylate, aryl acrylate or acrylate, phenol-formaldehyde resin, or combinations thereof.

The carrier film 21 can be the carrier 11 (see Fig. 1) or, depending on the type of the protected product and its manufacturing technology, it can be removed when placed in the window 13 (see Fig. 1) of the protected product 10 or removed when placed on carrier-based 11.

The protected article 10 contains applied or built into it a multilayer protective optical diffraction device 12 according to the invention, used in the form of a transparent window 13 in at least a part of the protected article. In this case, the protected product can be any valuable documents, including securities, banknotes, checks, credit cards, brands or products that are subject to protection from unauthorized access.

The separating layer 22 is made of synthetic wax compositions and has a thickness of 0.2-0.5 microns or can be made of an adhesive composition with a thickness of 3-5 microns, depending on the purpose of the protective device 12.

In this case, the surface of the first thermoplastic transparent polymer layer 23 together with the first metal layer 24 of the security device 12 is structured in relief in the form of diffractive structures. In this case, the areas occupied by the diffractive structures are designated as 23a, 23c on the first polymer layer 23 and areas 24a and 24c on the first metal layer, respectively. In this case, these diffraction structures contain at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the groove directions, depth and periods of grooves of said diffraction gratings and / or relief holograms and generated in accordance with predetermined algorithms software, depending on the required design of the generated color diffraction images, which contain hidden color security features that vary at the request of the manufacturer and transferred to the appropriate database by programs that provide the formation of color diffraction images stored in an opaque metallized diffraction region 14 ₁ , including containing hidden colored security features.

In this case, the spatial picture orientation of the strokes on the surface of the first thermoplastic transparent isotropic polymer layer 23 (hereinafter referred to as the first polymer layer 23) is made in such a way that the formation of various in shape and physical size sets of structures on the opaque metallized diffraction region 14 ₁ with each sides of the security device 12, which are sets or combinations of letters, numbers, fonts, two-dimensional barcodes, etc., containing at least one hidden security feature.

FIG. 2, only a fragment along the line A-A of the optical protective device 12 is conventionally presented. Taking into account the above, the first thermoplastic transparent isotropic polymer layer 23 is conventionally represented by only two of its sections 23a and 23c, but in practice the number of sections can be much larger over the entire area of the opaque metallized diffraction region 14 ₁ . In this case, the depth of the grooves between the grooves in the diffraction gratings in sections 23a and 23c ranges from 50 nm to 600 nm. The portions of the layer 23, conventionally located between the portions 23a and 23c, and not occupied by diffractive structures, represent a flat transparent demetallized surface (indicated by the dashed line in Fig. 2), which corresponds to the region 15 ₁ in Fig. 1. On the surface of the first thermoplastic transparent polymer layer 23, a first metal layer 24 (not shown in FIG. 2) is applied, consisting of regions 24a and 24c with a thickness of about 20 nm. In this case, sections 24a and 24c repeat the diffraction structures formed on the indicated patterned diffraction structures in sections 23a and 23c in the first thermoplastic transparent polymer layer 23 with groove depths between grating lines of 20-400 nm.

A second thermomlastic transparent isotropic polymer layer 25 (hereinafter referred to as the second polymer layer 25) is deposited on the surface of the sections 24a and 24c of the first metal layer 24 with a thickness of the order of 10-20 nm. In this case, the areas occupied by the diffractive structures are designated as 25a, 25c on the second polymer layer 25 and areas 26a and 26c on the second metal layer, respectively. The number of areas occupied by diffractive structures is conditionally limited to two areas, but there may be more than 2. The areas of layer 25, conventionally located between areas 25a and 25c, and not occupied by diffractive structures, represent a flat transparent demetallized surface (indicated by a dashed line in Fig. 2)), which corresponds to the area 15 ₂ in Fig. 1. In this case, these demetallized sections of the first and second thermoplastic transparent polymer layers 23 and 25 coincide in their composition and refractive index, equal to about 1.55-1.57. The second polymeric layer 25 has a thickness of about 1.5 μm and can be made of linear macromolecules of the class of one of polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins, etc.

As already mentioned, on the specified second polymer layer 25, including in areas 25a and 25c and the second metal layer 26 with areas 26a, 26c applied to the second polymer layer, a diffraction structure in the form of a relief hologram with non-positioned wallpaper patterns is applied by hot embossing. type, forming a set of color-variable holographic images. The specified diffractive structure in the form of a relief hologram provides the formation of a non-positioned wallpaper type on an opaque metallized diffraction region 14 ₂ .

The specified second metal layer 26 (shown in Fig. 2 sections 26a and 26c) has a thickness of about 20 nm and is made of a layer of metal or an alloy of metals, which is at least one element of aluminum, copper, brass, bronze, steel, zinc, tin, precious. metal or their alloys and includes sections 26a and 26c (layer 26 is shown in Fig. 2 sections 26a and 26c) completely repeating the relief-structured surface of sections 25a and 25c of the second polymer layer 25.

Next, there is a homogeneous optical layer 27 (hereinafter referred to as an optically transparent layer 27) made of linear macromolecules of the class of one of polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins, etc. The optically transparent layer 27 contains areas that repeat the relief-structured surface of the second metal layer 26.

On top of the optically transparent layer 27, a lacquer coating 28 is provided, spatially coinciding with the design of the optical security device 12.

Next, a method for manufacturing a multilayer protective optical diffractive device is disclosed with reference to FIG. 2:

On one side of the multilayer protective optical diffractive device, the following steps are performed.

1) A carrier film 21 is provided with a release layer 22 applied thereto (see FIG. 2).

In this case, the carrier film is made of polyethylene terephthalate (PET) or polypropylene (PP) and can have a thickness in the range from 12 to 100 microns. The separating layer 22 is made of synthetic wax compositions and has a thickness of 0.2-0.5 microns or can be made of an adhesive composition with a thickness of 3-5 microns.

2) On one side of the multilayer protective optical diffraction device 12, a first thermoplastic transparent isotropic polymer layer 23 (hereinafter referred to as the first thermoplastic layer 23) is uniformly applied to the separating layer 22.

In this case, the application of the first thermoplastic layer 23 is carried out by means of one of the printing methods: gravure printing method, offset printing method or flexographic printing method.

The first thermoplastic layer 23 has a thickness of 0.7-1.0 microns and is made of linear macromolecules of at least one of: polyurethane acrylate, epoxy acrylate, aryl acrylate or acrylate, phenol-formaldehyde resin, or combinations thereof.

3) On the first thermoplastic layer 23, the first metal layer 24 is evenly applied.

The first metal layer 24 is made of at least one of: aluminum, copper, brass, bronze, steel, zinc, tin, or their alloys and has a thickness of 10-20 nm with an optical density (D) equal to 0.8-1.2 ... In this case, the optical transmission of the first metal layer is 10% in the UV region of the spectrum.

4) On the surface of the first thermoplastic layer 23 with the first metal layer 24, the first information-bearing element is formed by the method of hot embossing while simultaneously forming in the first thermoplastic layer 23: sections 23a and 23c and in the first metal layer 24: sections 24a, 24c. In this case, the areas occupied by the diffractive structures are designated as 23a, 23c on the first polymer layer 23 and areas 24a and 24c on the first metal layer, respectively.

The number of areas occupied by diffractive structures is conditionally limited to two areas, but there may be more than 2. The areas of layer 23, conditionally located between areas 23a and 23c, and not occupied by diffractive structures, represent a flat transparent demetallized surface (indicated by a dashed line in Fig. .2), which corresponds to area 15 ₁ in Fig. 1.

In this case, the first information-bearing element consists of an opaque metallized diffraction region 14 ₁ and a transparent region 15 ₁ , in the form of a flat demetallized region made of a layer of thermoplastic polymer material.

4.1) while forming the first information-bearing element:

4.11) provide the first relief microstructuring of the surface of the first thermoplastic layer 23 with areas 23a, 23c with the first metal layer 24 applied to it with areas 24a, 24c in the form of diffraction structures containing at least one diffraction grating and / or a relief hologram with a picture distribution of directions strokes, depths and periods of strokes of the indicated diffraction gratings and / or relief holograms. In this case, diffraction gratings can have a picture angular and spatial distribution of grooves in the range from 0 to 179 degrees. In this case, the picture value of the spatial frequency of grooves in the region of the location of holographic images according to a given law can vary within 200-2000 lines / mm with a depth of grooves in the range of 20-400 nm and a given shape of their profile within these grooves. Macroscopically images of these gratings can represent different designs, including those with security features, depending on the purpose of the optical security device 12.

4.12) provides the specified first relief microstructuring of the surface of the first thermoplastic layer 23 with areas 23a, 23c with the first metal layer 24 applied to it with areas 24a, 24c by means of a nickel matrix-hologram with a first predetermined relief structuring of the surface at a temperature in the range of 90-130 ° C and a pressure in the range of 3.5-4.5 kg / cm ² .

In this case, the obtained first relief microstructuring of the surface forms a complete relief-bearing image of the security device 12. At the same time, the first relief microstructuring of the surface with a predetermined depth of grooves between the grooves of the diffraction gratings is provided, while, in particular, with a groove depth in the range from 50 to 400 nm , the formation of microcracks is ensured during the hot stamping process

In this case, the sections 24a and 24c of the first metal layer 24 repeat the diffraction structures in the form of relief holograms formed on the said diffraction structures of the sections 23a and 23c of the first thermoplastic layer 23.

It should be noted that the surface microstructuring of the surface of the first thermoplastic layer 23 and the second thermoplastic layer 25 is carried out using solid-state moth-eye metal matrices - holograms, for example, nickel matrix-holograms made from original holographic images using the Dot Matrix technology disclosed in the information source [R.L. van Renesse. Security aspect of commercially available dot matrix and image matrix origination systems, SPIE Inter. Conf.on Opt. Hologr. And its Applications, 24-27 May 2004, Kiev, Ukraine] and / or by the method of electron-beam lithography, disclosed [A.V. Goncharsky, V.V. Popov, V.V. Stepanov, "Introduction to computer optics", Publishing house of Moscow State University, 1991, p. 132].

4.13) provide the treatment of the first metal layer 24 after the hot stamping process with a solution of the chemical composition, for example, by means of photoinitiators of the radical cationic hardening mechanism. at least one diffraction grating and / or embossed hologram in regions 24a and 24c.

4.14) provide the etching of the first metal layer 24 by placing the carrier film 21 with layers 23, 24 in a chemical composition to ensure demetallization in smooth (flat) areas in which there are no diffraction structures in the form of at least one diffraction grating and / or relief holograms. These areas correspond to area 15 ₁ (Fig. 1) on the security device 12.

4.2) provide the formation of a second information-bearing layer, which consists of an opaque metallized diffraction region 14 ₂ and a transparent region 15 ₂ , in the form of a flat demetallized region made of a layer of thermoplastic polymer material

while in the process of forming the second information-bearing element:

4.21) is applied to the first metal layer 24 with areas 24a, 24c a second thermomlastic transparent isotropic polymer layer 25 (hereinafter referred to as the second polymer layer 25).

The second polymer layer 25 has a thickness of about 1.5 microns and is optionally made of linear macromolecules of the class of one of polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins

4.22) uniformly applied to the second polymer layer 25 a second metal layer 26 with a thickness of about 20 nm, made of a layer of metal or an alloy of metals, which is at least one element of: aluminum, copper, brass, bronze, steel, zinc, tin, precious metal or their alloys

4.23) provide a second relief microstructuring of the surface of the second polymer layer 25 with sections 25a and 25c with a second metal layer 26 applied to it with sections 26a, 26c in the form of diffractive structures. In this case, the areas occupied by the diffractive structures are designated as 25a, 25c on the second polymer layer 25 and as 26a and 26c on the second metal layer, respectively. The portions of the layer 25, conventionally located between the portions 25a and 25c, and not occupied by diffractive structures, represent a flat transparent demetallized surface (indicated by the dashed line in Fig. 2), which corresponds to the region 15 ₂ in Fig. 1. In this case, these demetallized sections of the first and second thermoplastic transparent polymer layers 23 and 25 coincide in their composition and refractive index.

The diffraction structures obtained by means of hot stamping contain at least one relief hologram with a picture distribution of the stroke directions, depth and periods of the strokes in the specified at least one relief hologram. In this case, the relief holograms have a picture angular and spatial distribution of strokes. In this case, the picture value of the spatial frequency of grooves in the region of the location of holographic images in relief holograms changes according to a given law within 200-2000 lines / mm with a depth of grooves in the range of 20-400 nm and a given shape of their profile within these grooves. Macroscopically, the images of these embossed holograms can represent different designs, including those with security features, depending on the purpose of the optical security device 12.

In this case, the relief hologram can be a relief hologram with non-positioned patterns. those. wallpaper hologram. In this case, the second information-bearing element consists of an opaque metallized diffraction region 14 ₂ and a transparent region 15 ₂ , in the form of a flat demetallized region made of a layer of thermoplastic polymer material.

4.24), the specified second relief microstructuring of the surface of the second thermoplastic layer 25 with the second metal layer 26 deposited thereon is performed by means of a nickel matrix-hologram with a second predetermined relief structuring of the surface. In this case, the obtained second relief microstructuring of the surface forms a complete relief-bearing image of the security device 12.

4.25) In this case, the design of at least one diffraction grating and / or relief hologram with a picture distribution of groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information-bearing element differs from the design of at least one relief hologram with non-positioned figures, i.e. wallpaper hologram, and with a picture distribution of the directions of the strokes, the depth and periods of the strokes in the specified embossed hologram of the second information-bearing element.

4.26) uniformly applied to the second metal layer 26 over the entire area of the security device 12, coinciding with the opaque metallized diffraction area 14 ₂ and the transparent area 15 ₂ , by printing, for example by gravure, letterpress offset printing or flexographic printing, a layer of positive photoresist (not shown in Fig. 1 and Fig. 2) with a thickness of 0.8 -1.0 microns.

4.27) uniformly exposing the positive photoresist layer of UV applied on the second metal layer 26 to UV radiation directed from the side of the first metal layer through the demetallized areas of the said first metal layer 24 acting as a transparent photomask (the step of demetallization of the first metal layer 24 was performed in step 4.14 ). In this case, the demetallized areas of the first metal layer 24 coincide with the demetallized area 15 _{1 of the} security device 12.

4.28, the exposed areas of the positive photoresist layer are removed in the areas of the second metal layer 26 corresponding to the demetallized areas of the first metal layer 24 through which UV exposure was performed in step 4.27 of the method. In this case, the removal of the exposed areas of the positive photoresist layer in the indicated areas of the second metal layer 26 is carried out by washing off the indicated exposed areas of the photoresist layer with an alkali or a developer.

4.29. the second metal layer 26 is demetallized at the remote exposed areas of the positive photoresist layer to form demetallized transparent areas corresponding to the transparent area 15 _{2 of the} security device 12.

4.30. over the second metal layer 26 and over the entire surface of the security device 12, on one side of it, an optically homogeneous layer 27 (hereinafter referred to as an optical transparent layer 27) is applied by pouring. The specified layer 27 completely repeats the relief structuring of the second metal layer 26 with relief (occupied by diffractive structures) and flat areas.

The optical transparent layer 27 is made of cured linear macromolecules of the class of one of polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins with a refractive index close to that of the first thermoplastic layer.

5. Apply a varnish coating 28 over the optically transparent layer 27 over the entire surface of the optical security device 12.

Thus, thanks to the manufacturing method developed by the authors, a multilayer protective optical diffractive device was created with significantly improved protective properties, which are provided by the formation of various diffraction structures, including diffraction gratings and / or holograms on both sides of the proposed multilayer protective device with an almost ideal spatial accuracy of relative position up to 5 microns, as a result of imparting to one of at least two metal layers with diffractive structures located on it, a property that prevents the effect of its demetallization at their locations and the formation of demetallized transparent regions of the other of at least two metal layers using a layer of positive photoresist, which makes it virtually impossible for unauthorized copying. And valuable objects, in the form of securities or other products, on which this multilayer protective optical diffractive device, produced by the method disclosed in the present description, is applied or embedded, have a unique multi-level degree of protection.

Industrial applicability

The invention can be used in the field of protection of objects, or products to be protected, in particular for the protection of valuable documents, any valuable products from counterfeiting and copying and identification of their authenticity.

Claims (57)

1. A method of manufacturing a multilayer protective optical diffractive device, comprising the steps of: 1) provide a carrier film; 2) a separating layer is applied on one side of the carrier film; 3) the first thermoplastic transparent isotropic polymer layer is evenly applied to the separating layer; 4) evenly applying the first metal layer on the specified first thermoplastic transparent isotropic polymer layer; 5) by hot embossing, at the same time, on the surface of the first thermoplastic transparent isotropic polymer layer and the first metal layer, a first information-bearing element is formed containing at least one opaque metallized diffractive region and at least one transparent region; 5a) in this case, the formation of the first information-bearing element contains the stages at which: 5a1) provide relief microstructuring of the surface of the first thermoplastic transparent isotropic polymer layer with the first metal layer applied thereto with the formation of diffraction structures containing at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the groove directions, with predetermined depth and period of grooves in said diffraction gratings and / or relief holograms with the provision of microcracks located along the grooves over the entire area occupied by said diffraction gratings and / or relief holograms, the formed diffraction structures of the first thermoplastic transparent isotropic polymer layer completely repeat the diffraction structures of the first metal layer; 5a2), a layer of a liquid composition with reactive additives is applied to the first metal layer with embossed diffractive structures to ensure the process of diffusion of the specified liquid composition through microcracks into the first thermoplastic transparent isotropic polymer layer, providing it with an intermolecularly cross-linked three-dimensional structure and ensuring resistance to demetallization areas of the first metal layer with embossed diffractive structures; 5a3) provide the etching of the first metal layer to ensure demetallization in areas where there are no diffractive structures; - the second thermoplastic transparent isotropic polymer layer is evenly applied to the first metal layer; 6) evenly applying the second metal layer to the second thermoplastic transparent isotropic polymer layer; 6a) by hot stamping, at the same time, on the surface of the second thermoplastic transparent isotropic polymer layer and the second metal layer, a second information-bearing element is formed, comprising at least one opaque metallized diffractive region and at least one transparent region; in this case, the formation of the second information-bearing element contains the stages at which: 6a1) provide relief microstructuring of the surface of the second thermoplastic transparent isotropic polymer layer with a second metal layer deposited on it in the form of diffraction structures containing at least one relief hologram with a predetermined second picture distribution of strokes directions, with a predetermined depth and period of strokes in said relief holograms; 6a2) at the same time formed in step 6a1) at least one relief hologram of the second thermoplastic transparent isotropic polymer layer completely repeats at least one relief hologram of the second metal layer; in this case, the design of at least one diffraction grating and / or relief hologram with a predetermined first picture distribution of groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information carrier differs from the design of at least one relief hologram with a predetermined second picture distribution of the directions of the strokes, the depth and periods of the strokes in the specified relief hologram of the second information-bearing element; 7) a layer of positive photoresist is evenly applied to the second metal layer over the entire area of the security device; 8) uniformly exposing the positive photoresist layer applied to the second metal layer with UV radiation directed from the side of the first metal layer through the demetallized portions of said first metal layer, functioning as a transparent photomask; 9) removing the exposed areas of the positive photoresist layer in the areas of the second metal layer corresponding to the demetallized areas of the first metal layer through which UV exposure was carried out; demetallizing the second metal layer at the remote exposed areas of the positive photoresist layer to form demetallized transparent areas; 10) a homogeneous optically transparent layer is applied on one side of the second metal layer and over the entire surface of the security device, while this layer completely repeats the relief structure of the second metal layer; 11) apply a varnish coating over a uniform optically transparent layer and over the entire surface of the optical security device. 2. The method of claim 1, wherein the carrier film is made of polyethylene terephthalate (PET) or polypropylene (PP). 3. A method according to claim 1, wherein the separating layer is made from synthetic wax compositions or from an adhesive composition. 4. The method according to claim. 1, in which the application of the first thermoplastic transparent isotropic polymer layer on the separating layer is carried out by a printing method, which is one of: gravure printing method, offset or flexographic printing method. 5. The method according to claim 1, wherein the first thermoplastic transparent isotropic polymer layer is made of linear macromolecules of at least one of polyurethane acrylate, epoxy acrylate, aryl acrylate or acrylate, phenol-formaldehyde resin, or combinations thereof. 6. The method according to claim. 1, in which the first metal layer is made of at least one of: aluminum, copper, brass, bronze, steel, zinc, tin or their alloys and has an optical transmission of 10% in the UV region of the spectrum. 7. The method according to claim 1, in which the first information-bearing element consists of an opaque metallized diffractive region and a transparent region in the form of a flat demetallized region made of a layer of thermoplastic polymer material. 8. The method according to claim. 1, in which the relief microstructuring of the first thermoplastic transparent isotropic polymer layer is performed in such a way that the formed diffraction structures have a predetermined picture angular and spatial distribution of grooves and a predetermined value of the spatial frequency of grooves in the region of holographic images. 9. The method according to claim 1, wherein the diffraction structures formed at the stage of the first relief microstructuring of the first thermoplastic transparent isotropic polymer layer form pictures with a different predetermined design. 10. The method according to claim 1, wherein the layer of the liquid composition with reactive additives applied to the first metal layer in step 5a2) is a liquid composition based on radical polymerization photoinitiators of the 2,2-dimethoxy-2-phenylacetophenone type (Irgacure -651) with reactive additives in the form of active diluents such as isobornyl acrylate. 11. The method according to claim 1, in which the layer of the liquid composition with reactive additives applied to the first metal layer in step 5a2) is a liquid composition based on photoinitiators containing a benzoyl group with radical cationic cure mechanism substituents containing tanning substances, for example benzophenone and its alkyl derivatives. 12. The method of claim 1, wherein the etching step 5a3) is performed by placing the carrier film coated with the first thermoplastic transparent isotropic polymer layer and the first metal layer in an acetic acid and nitric acid solvent. 13. The method according to claim 1, wherein the second thermoplastic transparent isotropic polymer layer is made of linear macromolecules of at least one of polyurethane acrylate, epoxy acrylate, aryl acrylate, acrylate, phenol-formaldehyde resin, or combinations thereof. 14. The method of claim 1 or 13, wherein the second thermoplastic transparent isotropic polymer layer has a thickness of about 1.5 microns. 15. The method of claim 1, wherein the second metal layer has a thickness of about 20 nm. 16. The method of claim. 1, wherein the second metal layer is made of at least one of: aluminum, copper, brass, bronze, steel, zinc, tin, precious metals or their alloys. 17. The method according to claim. 1, in which at the stage of performing relief microstructuring of the second thermoplastic transparent isotropic polymer layer formed relief holograms are holograms with non-positioned patterns such as wallpaper holograms. 18. The method according to claim 17, wherein at the stage of performing relief microstructuring of the second thermoplastic transparent isotropic polymer layer, the formed wallpaper holograms have a predetermined picture angular and spatial distribution of strokes and a predetermined value of the spatial frequency of strokes in the region of the location of the holographic images. 19. The method according to claim. 17, in which the wallpaper holograms formed at the stage of relief microstructuring of the second thermoplastic transparent isotropic polymer layer form pictures with a different predetermined design. 20. The method according to claim 1, in which there is provided the step of relief microstructuring of the surface of the first thermoplastic transparent isotropic polymer layer at step 5a1) by means of a nickel matrix-hologram with the first predetermined relief structuring of the surface and the step of relief microstructuring of the surface of the second thermoplastic transparent isotropic polymer layer at the stage 6a1) by means of a nickel hologram matrix with a second predetermined relief structuring of the surface, wherein the relief structuring of the surface of the first thermoplastic transparent isotropic polymer layer differs from the second structuring of the surface of the second thermoplastic transparent isotropic polymer layer. 21. A method according to claim 1, wherein the step of applying a layer of positive photoresist to the second metal layer is carried out by a printing method that is a gravure, letterpress offset or flexographic printing method. 22. The method according to claim 1, wherein the step of removing the exposed areas of the positive photoresist layer in said areas of the second metal layer is carried out by washing off said exposed areas of the photoresist layer with an alkaline developer based on an aqueous solution of tetramethylammonium hydroxide or trimethyl (2-hydroxyethyl) ammonium hydroxide with a fluorine surfactant, 23. The method according to claim 1, wherein the uniform optically transparent layer is made of cured linear macromolecules of one of: polyurethane acrylates, epoxy acrylates, aryl acrylates or acrylates, phenol-formaldehyde resins. 24. The method of claim 23, wherein the uniform optically transparent layer and the first and second thermoplastic transparent isotropic polymer layers have substantially the same refractive index. 25. Multilayer protective optical diffractive device, made according to the method according to one of claims. 1-24, containing the carrier film and applied thereto: at least two thermoplastic transparent isotropic polymer layers, at least two metal layers, a uniform optically transparent layer; and a lacquer coating located over the entire surface of the optical security device; wherein at least two thermoplastic transparent isotropic polymer layers and at least two metal layers are made in such a way that the formation of at least two information-bearing elements is ensured; in this case, the first information-bearing element is made in the form of at least one diffraction grating and / or at least one relief hologram with a predetermined first picture distribution of the groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms and providing microcracks located along the grooves over the entire area occupied by the indicated diffraction gratings and / or relief holograms; the second information-bearing element is made in the form of at least one embossed hologram with a predetermined second picture distribution of the directions of the strokes, the depth and periods of the strokes in the said embossed wallpaper-type holograms; in this case, the design of at least one diffraction grating and / or relief hologram with a predetermined first picture distribution of groove directions, depth and periods of grooves in said diffraction gratings and / or relief holograms of the first information carrier differs from the design of at least one relief hologram wallpaper type with a predetermined second picture distribution of the directions of the strokes, the depth and periods of the strokes in the specified relief hologram of the second information-bearing element. 26. A protected product containing applied or built into it a multilayer protective optical diffractive device according to claim 25. 27. A security article according to claim 26, comprising a multilayer security optical diffractive device that is used as a transparent window in at least a portion of the security article. 28. A secured product according to claim 26, which is a valuable document including securities, banknotes, checks, credit cards, stamps. 29. A value document comprising a multilayer security optical diffractive device according to claim 25, used as a transparent window in at least a portion of the value document. 30. The value document according to clause 29, representing securities, banknotes, checks, credit cards, stamps.

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