ES2779923T3 - Security foil or document that has one or more enhanced watermarks - Google Patents

Abstract

Security foil or document (10) having one or more watermarks (14) or enhanced watermark designs, comprising: a fibrous sheet material that includes one or more watermarks or watermark designs, in where each watermark design has one or more first regions (18) with reduced fiber densities relative to surrounding regions of the fibrous sheet material and one or more second regions (16) with similar or greater fiber densities relative to surrounding regions of sheet material, and wherein each watermark design has a top or front and a bottom or back; and means for enhancing the one or more watermarks or watermark designs by making them visually enhanced, detectable or machine readable, or both, said means being characterized by the fact that they comprise: one or more transparent areas or translucent elements that surround each of the one or more watermark designs.

Description

DESCRIPTION

Security foil or document that has one or more enhanced watermarks

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of US Patent Application Serial No. 12 / 997,390, filed February 23, 2011, and claims benefit and priority of Provisional US Patent Application No. 61 / 911,141, filed on February 3, 2011. December 2013, US Provisional Patent Application No. 61 / 911,831, filed December 4, 2013, US Provisional Patent Application No. 61 / 911,885, filed December 4, 2013, and US Patent Application provisional n ° 61 / 924,000, filed on January 6, 2014.

TECHNICAL FIELD

The invention relates generally to a security foil or document having one or more enhanced watermarks.

BACKGROUND AND DESCRIPTION OF THE INVENTION

The invention is defined by the appended claims.

Security papers are used for the manufacture of security documents such as banknotes, passports, postage stamps, and the like. Conventionally, a wide variety of security features are incorporated or surface-mounted in such security papers. Known examples of such security features include watermarks, windowed and embedded security threads, fluorescent pigments, and the like.

Watermarks, which are recognizable images or patterns on paper that appear as various shades of light / dark when viewed by transmitted light or reflected light on a dark background, have provided protection against forgery of security documents for hundreds of years . In fact, watermarks and their attractive designs are the most recognized security feature available to the general public for the authentication of security documents such as banknotes.

As an example, US 2013/0255896 A1 describes a sheet that includes a high definition, high contrast watermark with areas of pronounced gloss. Said watermark is obtained in particular by means of a part that includes a surface having a raised area and perforations. The perforations are such that the realization of their cross section, at a certain distance from the drainage surface, depends directly on said distance. This document also shows a manufacturing process for said part that is used to form one of said watermarks, on the part itself, and the use of said part when forming a watermark.

Furthermore, EP 1743778 A2 describes a process for the production of colored watermarks which includes the use of a watermark applicator to which colored auxiliary material is supplied. The watermark applicator includes a cylinder with an open structure (similar to the open body of a pressure roller) and covered with an embossed metal mesh.

There is, however, a persistent need to improve the security or resistance to forgery of watermarked security documents.

The present invention addresses this need by providing improved, and therefore more resistant to, watermarks on paper and paper-like materials. Specifically, the present invention features a security sheet or document having one or more enhanced watermarks, the sheet or document comprising:

a fibrous sheet material including one or more watermarks, wherein each watermark has one or more first regions of reduced fiber density relative to surrounding regions of the fibrous sheet material and one or more second regions with similar fiber densities or greater relative to surrounding regions of the sheet material, and wherein each watermark design has a top or front and a bottom or back; and

means for enhancing the one or more watermarks by making them visually enhanced, machine readable / detectable, or both, said means comprising:

one or more transparent or translucent areas surrounding each of the one or more watermarks.

In a first exemplary embodiment, the security foil or document of the invention is a single or multi-layer paper comprising:

a first paper layer including one or more watermarks, each surface of the paper layer showing the top or front of the watermark (s) or its bottom or back;

one or more film-like or sheet-like security elements that at least partially cover the top or front or the bottom or back of the one or more watermarks; and optionally

a second layer of paper having a reduced basis weight compared to the first layer of paper and optionally one or more through windows, with the second layer of paper covering the top or front or the bottom or back of the one or more marks of water.

The film-like or sheet-like security element preferably has a different color from the watermark (s) and the surrounding paper thereby enhancing the appearance of the underlying watermark (s). or overlying watermark (s) as well as enhancing the contrast between the underlying or overlying watermark (s) and the surrounding paper.

In one such embodiment, the film-like or sheet-like security element (s) is (are) a micro-optical security device that projects one or more synthetic images such as the micro-optical security device. MOTION® Optical which is described, for example, in US Patent No. 7,333,268. Such devices display colored images on a transparent or tinted background and are thus suitable for use in combination with underlying printed information. It has been observed that these safety devices appear to give the watermark (s) a multi-hued look. As those skilled in the art will readily appreciate, multi-hued watermarks present an even greater challenge to a counterfeiter.

In a preferred embodiment, the micro-optical security device is in the form of a patch applied to the surface that covers all or part (for example, half) of a watermark, the watermark containing one or more polymers or materials. resinous within the first and / or second region of the watermark, the one or more polymers or resinous materials exhibiting a refractive index or combined (final) refractive index substantially similar to that of cellulose. In such an embodiment, the region (s) also contain (s) one or more features selected from the group of areas of higher fiber density in the form of recognizable or discernible markings, one or more color-imparting substances, and one or more more second-level security features that are machine-detectable or machine-readable (for example, UV or infrared reactive, luminescent, thermochromic, photochromic, electrochromic, metallic or magnetic security fibers, markers, planchettes, dyes, pigments).

As will be readily appreciated by those skilled in the art, the micro-optical security device may also be in the form of a strip, strip, grain, or elongated security thread applied to the surface, or a strip, strip, grain, or thread partially embedded elongated security that is present in windowed regions of a second layer of paper (ie, windowed yarn).

Micro-optical devices such as the MOTION® device can be designed so that, when aligned with the watermark (s), the synthetic images projected in this way are combined with the design of the mark (s). (s) of water. For example, in the aforementioned embodiments, the synthetic images generated by each patch can be coordinated or joined with the watermark design (s). Synthetic image (s) can also complete the watermark design (s) or be placed within the design (s). As will be explained in more detail below, this can be a one-sided or two-sided feature.

In another embodiment, the micro-optical security device (s), which is also described, for example, in US Patent No. 7,333,268, displays color images (of any color , including black and white) or a translucent or substantially opaque background of a different color. In this embodiment, the micro-optical security device (s) at least partially cover and visually camouflage the top or front of the one or more watermarks, or the bottom or back of the one or more watermarks. The water mark (s) is (are) not visually discernible in light reflected from the covered side of the paper layer, but is visually evident in light reflected from the uncovered side of the paper layer, and in light transmitted from both sides of the paper layer.

An inherent benefit in exemplary embodiments of the present invention that employ a partially or fully overlying or underlying film-like or sheet-like security element, such as MOTION® security device, is the longest durability of each brand of water. As is well known to those of skill in the art, one of the primary requirements of banknotes and other security documents is that the document and its security features must withstand the effects of circulation. These documents / features must be durable (i.e. resistant to damage from bending, tearing and dirt) and resistant to moisture and chemical absorption. Covering all or part of the watermark (s) with an applied film, foil, band, strip, grain, thread, or patch serves to physically protect the watermark (s) from damage during circulation. and handling, thereby increasing its durability.

Due to the increased durability conferred on these watermarks, it has been determined that these watermarks can be made larger and that the total area within each watermark occupied by regions of reduced fiber density (i.e., first regions) can be increased and these regions can be made thinner. Specifically, it has been found that these regions of reduced fiber density can be made with thicknesses as low as 10 to 15 microns, with total thicknesses ranging from about 10 to about 60 microns. The total area occupied by these regions of reduced fiber density within each watermark varies between about 5 and about 75 percent (%) of the total area of the watermark, preferably between about 20 and about 60. %. Additionally, the total area occupied by each watermark within a banknote measuring approximately 10,000 square millimeters (mm2) can vary between approximately 5 and approximately 25%, denoting an increase in size compared to the conventional watermarks of about 5%.

The present inventors have also made the surprising discovery that micro-optical devices such as the MOTION® device can also offer a detectable / machine-readable feature in the form of infrared enhanced brightness, especially when measured in transmission. The term "infrared enhanced brightness", as used herein, is intended to refer to infrared transmission levels at least 5% greater than (preferably more than 10% than) the infrared transmission levels of the paper. background. Infrared transmission levels can be measured using an optical sensor with a sensitivity equal to or greater than 830 nanometers (nm) and projecting an infrared light source with a wavelength greater than 800 nm through the sample. To make the infrared glow a reliable machine-readable characteristic, it is preferable that the micro-optical device is manufactured using one or more infrared transparent elements (for example, an infrared transparent ink) and does not contains infrared absorbing elements (eg infrared absorbing inks). It is also preferred that infrared absorbing elements are not present in areas near the device on the front and back of the paper layer (s). In one such embodiment, the micro-optical device is a security thread (eg, a MOTION® security thread) that does not contain infrared absorbing elements. In this embodiment, the micro-optical security thread is made using an infrared transparent ink (for example, an ink comprising pigments and / or dyes that do not absorb infrared) for microprinting and areas on the front and back of the Paper layer (s) in at least two-thirds (2/3) of the length of the security thread that does not contain infrared absorbing elements.

In addition to the at least partially overlying or underlying micro-optical device, one or more additional security features may be contained in or within the first and / or second region of the one or more watermarks. In one such embodiment, the watermark (s) do not contain one or more polymers or resinous materials within the first and / or second region. Additional security features are selected from the group of areas of highest fiber density in the form of recognizable or discernible markings, one or more color-imparting substances, and one or more second-level security features that are machine-detectable or readable. by a machine, as described above.

In a second exemplary embodiment, the security paper of the invention is a multilayer paper comprising:

a first layer of paper that has a low basis weight (for example, between about 10 and about 50 grams per square meter (g / m2)) and includes one or more watermarks, showing each surface of the first layer of paper the top or front of one or more watermarks or the bottom or back of the same; and

a second layer of paper having a low basis weight (e.g., between about 10 and about 50 g / m2) and optionally one or more through windows, with the second layer of paper covering the surface of the first layer of paper showing the top or front of one or more watermarks or the surface showing the bottom or back of the one or more watermarks.

In one such embodiment, the second paper layer has windows, the one or more through windows of the second paper layer are aligned with the top or front or the bottom or back of the one or more watermarks. By means of this second example embodiment, the use of two layers of paper and optionally one or more overlying or underlying windows allows greater contrast between the one or more watermarks and the background. The one or more overlying or underlying windows act in a manner similar to that of an electrotype, occupying paperless regions or thinner paper regions resulting in regions brighter than the background in each paper / watermark region.

In a third exemplary embodiment, within the first and / or second region of the one or more watermarks is contained one or more security features in the form of one or more color-imparting substances. The one or more color-imparting substances include dyes and pigments (eg, ultrafine particle size pigments). In this embodiment, the security sheet or document does not include one or more film-like or sheet-like security elements. The resulting watermarks have a hue (that is, color scheme or range of tones) in a different color or hue than the bulk region of the material surrounding the watermark. The watermarks of the invention serve to increase the perception and resistance to simulation of existing watermarks.

In a fourth exemplary embodiment, one or more polymers or resinous materials are contained within the first region (s) and optionally the second region (s) of the one or more labels. of water. As before, the security sheet or document in this exemplary embodiment does not include one or more film or sheet-like security elements. The first and / or second region in this embodiment may also contain one or more security features selected from the group of areas of higher fiber density in the form of recognizable or discernible markings, one or more color-imparting substances, and one or more Second-level security features that are machine-detectable or machine-readable, as described above.

In a fifth exemplary embodiment, the security foil or document of the invention is a single layer paper comprising:

a layer of paper that includes one or more watermarks; and

one or more transparent or translucent areas in the paper layer surrounding each of the watermarks, thereby weaving together and thus enhancing the visual perception of the watermark (s).

Other characteristics and advantages of the invention will be clear to a person skilled in the art from the following detailed description and the accompanying drawings.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, this report, including definitions, will prevail. Furthermore, the materials, procedures / processes, and examples are illustrative only and are not intended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The present description can be better understood with reference to the following drawings. Components in the drawings are not necessarily to scale, emphasis is instead placed on clearly illustrating the principles of the present disclosure. Although exemplary embodiments are described in connection with the drawings, it is not intended to limit the present description to the embodiment (s) described herein. Rather, the intent is to cover all alternatives, modifications, and equivalents.

The particular characteristics of the described invention are illustrated with reference to the attached drawings in which:

Figure 1 is an image of a watermark (shield number 30) with an overlying MOTION® security patch or within an example security paper viewed in daylight (reflected light from the visible spectrum) and under infrared transmitted light from the front or face of the security paper, with the watermark and patch displayed at an enlarged scale for clarity;

Figure 2a is another image of the watermark of Figure 1 with an overlying security patch that is again seen in daylight (light reflected in the visible spectrum) and under transmitted infrared light from the visible side of the paper. security, the image magnified but to a lesser degree than figure 1, while figures 2b-d are enlarged images of the same watermark with the overlying security patch shown in transmitted infrared light from the back side of the security paper (figure 2b), in reflected infrared light from the visible side of the security paper (figure 2c), and in reflected infrared light from the back of the security paper (figure 2d);

Figure 3a is another image of the watermark of Figure 1 with an overlying security patch viewed in daylight (visible light reflected in the spectrum) from the face side of the security paper, the image enlarged but to a lesser degree than figure 1, while figures 3b-d are enlarged images of the same watermark with the overlying security patch shown in the reflected light of the spectrum visible from the back side of the security paper (figure 3b), in visible spectrum transmitted light from the face side of the security paper (Figure 3c), and in visible spectrum transmitted light from the back side of the security paper (Figure 3d);

Figure 4 is a schematic diagram of a modified double strand or Fourdrinier papermaking machine whereby watermarks are incorporated along the machine direction of a web of forming paper through a roll cylinder pressure, and by which a security element in the form of an elongated security thread is applied to a surface of the watermarked paper web before the wet pressing section of the machine. The machine employs a means for the machine direction alignment of the watermarks and the elongated security thread on the paper web. This method of making the sheet material of the invention does not shift the fiber distribution, resulting in a higher fiber distribution with higher density and substrate stiffness that resists deformation, distortion and bending of the security thread;

Figure 5 is a schematic diagram of another modified Fourdrinier or double filament papermaking machine through which an elongated security thread is introduced onto a surface of the fibrous web at the same time or just before it is incorporated ( n) the water mark (s) and before the wet press section of the machine. The machine employs means for machine direction alignment of the elongated security thread and the water mark (s) on the fibrous web. This process for making the fibrous sheet material of the present invention results in the fiber flowing around the yarn, resulting in a lower density fiber distribution with reduced density and stiffness under yarn applied to the surface;

Figure 6 is a schematic diagram of a papermaking machine composed of two cylinder paper machines connected to each other by a collecting felt, where an elongated security thread contacts a watermarked paper web formed by a roll paper machine before joining a second paper web formed by the other roll paper machine. This machine also employs means for the machine direction alignment of the elongated security thread and the water mark (s) to the first web of paper;

Figure 7 provides, in side-by-side comparison, enlarged images of a prior art watermark and an exemplary embodiment of the improved watermark of the invention, which has a strikingly bright or intense appearance;

Figure 8 provides, in side-by-side comparison, enlarged images of an exemplary embodiment of the watermark of the invention employing a second-level UV-excitable security feature in both transmitted light and UV light. ;

Figures 9a, b are schematic drawings depicting a method for making an exemplary embodiment of the paper security document of the present invention;

Figure 10 is an enlarged image of a wet fiber mat or sheet on a papermaking machine (viewed in reflected light on a dark background) with paper removed in selected areas of the sheet with a resulting reduction in density of fiber in those selected areas. The selected areas are circular in shape and are shown in two different sizes, the larger selection areas also containing a circular area of higher fiber density; and

Figure 11a, b are enlarged images of the surrounded selection area shown in Figure 10 (views in transmitted light) after treatment with one or more polymers or resinous materials having a refractive index or combined index of refraction substantially similar to that of cellulose. The first enlarged image (Figure 11a) shows the circular area within the selection area that has a color similar to that of the surrounding fiber mat or sheet, while the second enlarged image (Figure 11b) shows that the printed material viewed under this Example embodiment of the security element of the invention is clearly legible.

DETAILED DESCRIPTION OF THE INVENTION

By the present invention, watermarks formed on or within a security foil or document are improved, making the security foil or document more resistant to counterfeiting.

The sheet or document of the invention, as indicated above, comprises: a fibrous sheet material that includes one or more watermarks; and means for enhancing the one or more watermarks by making them visually enhanced, machine detectable / readable, or both.

Fibrous webs suitable for use in the present invention are paper or paper-like webs. These sheet materials, which are single-layer or multi-layer materials, can be made from a range of fiber types including synthetic or natural fibers or a mixture of both. For example, these sheet materials can be made of fibers such as abaca, cotton, flax, wood pulp, and mixtures thereof. As is well known to those skilled in the art, cotton and cotton / linen or cotton / synthetic fiber blends are preferred for banknotes, while wood pulp is commonly used in non-bank security documents.

Watermarks can be formed on the fibrous sheet material using known procedures and techniques. For example, watermarked sheet material can be made on a roll mold papermaking machine (using stamped wire cloth, or by applying a thin piece of metal, usually in the form of an image or letter, to the wire cloth) , or it is a Fourdrinier paper making machine (using a pressure roller).

Next, exemplary embodiments of the security foil or document of the invention will be described in which various means are used to enhance the watermark (s), and their respective manufacturing processes.

In a first exemplary embodiment, the security foil or document of the invention is a single or multi-layer paper comprising (a) a first layer of paper that includes one or more watermarks, each surface of the layer showing paper the top or visible side of the watermark (s) or its bottom or back, (b) one or more film-like or sheet-like security elements that have a different color from the Watermark (s) covering (s) at least partially the top or visible face or the back of the watermark (s), and optionally (c) a second layer of paper having a reduced basis weight compared to the first layer of paper (for example, between about 10 and about 50 g / m2) and optionally one or more through windows, with the second layer of paper covering the top or front or the bottom or back of the water mark (s).

The film-like or sheet-like security element (s) used in the practice of the present invention is (are) limited only by their film-like or sheet-like structure, with structures contemplated having overall thicknesses ranging from about 15 to about 100 microns (preferably, from about 15 to about 50 microns). The film-like or sheet-like structures can take any shape, including, but not limited to, bands, strips, veins, threads, or patches. They can display or project information that is humanly perceptible either directly or with the aid of a device and / or incorporate information that is detectable / readable by a machine. The structures may be segmented into regions, showing or projected or otherwise the information being contained in some or all of these regions that are the same or different.

Suitable film-like or sheet-like security features may employ one or more of the following: demetallized or selectively metallized, magnetic, magnetic, and metal blended regions or layers, or stamped (e.g., blind embossing), coatings that change from color made in color-changing, iridescent, liquid crystal, photochromic and / or thermochromic materials, coatings of luminescent and / or magnetic materials, holographic and / or diffractive security features and micro-optical security features.

In a preferred embodiment, the security element (s) is (are) a micro-optical structure. As noted above, such structures project one or more synthetically enlarged optical images, and generally comprise: (a) a light-transmitting polymeric substrate; (b) an array of micro image icons located on or within the polymeric substrate; and (c) an array of microlenses. The icon and micro lens arrays are configured such that when the icon array is viewed through the micro lens array, one or more synthetically enlarged optical images are projected. These projected images can display a number of different optical effects. Such structures are described in US Patent No. 7,333,268 to Steenblik et al., US Patent No. 7,468,842 to Steenblik et al., US Patent No. 7,738,175 to Steenblik et al., International Patent Publication No. WO 2005/106601 A2 to Commander et al., And International Patent Publication No. WO 2007/076952 A2 to Kaule et al. In one such embodiment, a micro-optic structure is employed as described in US Patent No. 7,333,268 to Steenblik et al. (Eg, the MOTION® micro-optic security device), the structure being formed to starting from a polymeric substrate prepared using one or more essentially colorless polymers selected from the group that includes, but is not limited to, polyester, polyethylene, polyethylene terephthalate, polypropylene, polyvinyl carbonate, polyvinylidene chloride, and combinations thereof.

In a more preferred embodiment, the micro-optical security device is in the form of a patch applied to the surface that covers all or part (for example, half) of a watermark, the watermark containing one or more polymers or materials. resinous within the first and / or second region thereof, the one or more polymers or resinous materials exhibiting a refractive index or combined (final) refractive index substantially similar to that of cellulose. The first and / or second region of the watermark may also contain one or more characteristics selected from the group of areas of higher fiber density in the form of recognizable or discernible marks, one or more color-imparting substances, and one or more characteristics. Second-level security features that are machine-detectable or machine-readable, as described above.

In another more preferred embodiment, the micro-optical security device is in the form of an elongated strip or thread applied to the surface, or a partially embedded elongated security strip or thread that is present in windowed regions of a second layer of paper (ie say, thread with windows). The strip or thread in this embodiment covers all or part of the water mark (s).

In an even more preferred embodiment, the micro-optical security device (eg, the MOTION® device) is designed so that, when aligned with the watermark, the synthetic images projected thereby blend into the design. of the watermark. For example, in the aforementioned embodiments, the synthetic images generated by each patch or thread can be coordinated or joined with the watermark design. Synthetic images can also complete the watermark design (s) or be placed within the design (s). This can be a single or double sided feature. In other words, the complete information intended to be conveyed to the viewer is not supplied solely by the watermark or the synthetic image (s), but requires both to be viewed simultaneously. In one such example, when viewed at the optimal angle of view (perpendicular) using transmitted visible spectrum light, the MOTION® patch projects a synthetic image in the form of a coating that overlays (aligned) the watermark design on shield shape. When the angle of view is moved out of alignment, the synthetic image and the watermark design are no longer aligned with each other, and the watermark design (shield and number 30) would be seen inside the patch and the synthetic image. I would pass or change the layer to, for example, an array of numbers.

An inherent benefit of exemplary embodiments of the present invention that employ a partially or fully overlying or underlying film-like or sheet-like security element, such as the MOTION® micro-optical security device, is the increased durability of each watermark. Covering all or part of the watermark with an applied film, foil, band, strip, grain, thread, or patch serves to physically protect the watermark (s) from damage during circulation and handling, increasing the this way its durability.

Due to the increased durability conferred on these watermarks, it has been determined that these watermarks can be made larger and that the total area within each watermark occupied by regions of reduced fiber density (i.e., first regions) can be increased and these regions can be made thinner. Specifically, it has been found that these regions of reduced fiber density can be made with thicknesses as low as 10 to 15 microns, with total thicknesses ranging from about 10 to about 60 microns. The total area occupied by these regions of reduced fiber density within each watermark varies between about 5 and about 75 percent (%) of the total area of the watermark, preferably between about 20 and about 60. %. Furthermore, the total area occupied by each watermark within a banknote measuring approximately 10,000mm2 can vary between approximately 5 and approximately 25%, denoting an increase in size compared to conventional watermarks. of about 5%.

The present inventors have also made the surprising discovery that micro-optical devices such as the MOTION® device can also offer a detectable / machine-readable feature in the form of infrared enhanced brightness, especially when measured in transmission. To make infrared glow a reliable machine-readable feature, it is preferred that the micro-optical device is manufactured using one or more infrared transparent elements (for example, an infrared transparent ink) and does not contain absorbent elements. infrared (for example, infrared absorbing inks). It is also preferred that no infrared absorbing elements are present in areas close to the device on the face and back of the paper layer (s).

Referring now to Figure 1, one of said embodiments of the security foil or document of the invention is shown and is indicated by reference number 10). The micro-optical device is a MOTION® 12 safety patch that does not contain infrared absorbing elements. Patch 12 is positioned over a shield-shaped watermark 14 in which dark regions made up of fibers deposited more densely than normal base fiber density (i.e., second regions) 16 occupy the outer perimeter, regions spans made up of fibers deposited less densely than normal base fiber density (ie, first regions) 18 occupy the area within the shield pattern with the region occupied by number 30 made up of even lighter or less dense regions. The watermark 14 with the overlying MOTION® security patch 12 in Figure 1 is shown in daylight and under transmitted infrared light, with the watermark and patch illustrated at an enlarged scale for clarity.

As will be readily apparent from the display of Figure 1, the number 30 is very bright as a result of the overlapping patch. Here, the infrared brightness is correlated to the intensity of the infrared signal which, as indicated above, is measured in transmission using an optical sensor with a sensitivity equal to or greater than 830 nm and projecting an infrared light source with a wavelength greater than 800 nm through the sample. The infrared brightness can be controlled by the infrared properties of the ink used for the microprinting of the security patch 12. Microprinting in the form of micro icons of images located on or within a polymeric substrate is performed using a printing method (eg, inkjet, laser, letterpress, flexo, engraving, intaglio, and dye-sublimation printing processes), or using a microstructure approach. In the latter case, the image icons would be realized as voids or cavities in the substrate (for example, cavities measuring, for example, between about 0.5 and about 8 microns in total depth), or as structures raised relative to the substrate. (eg, tall structures (colored or colorless) measuring, for example, between about 0.5 and about 8 microns in total height). An infrared transparent material (for example, ink comprising pigments and / or pigments that do not absorb infrared) would be used to form the icons, for example by printing, coating or partially or completely filling the cavities or areas surrounding the raised structures, or forming raised structures (colored or colorless). It is preferred that the areas on the front and back side of the paper layer (s) at a distance of about 5 millimeters from an outer edge of the patch do not contain infrared absorbing elements.

Regarding the appearance of the embodiment of figure 1, and as shown in figures 2a-d and 3a-d:

(a) In the transmission of infrared or transmitted infrared light from the front or face of the document, the watermark (shield and number 30) and a faint overlay of the patch would be seen (see figure 2a);

(b) In the infrared transmission from the back of the document, the watermark (shield and number 30) would be seen in reverse and a darker patch overlay (see figure 2b);

(c) In the infrared light reflected from the face of the document, the watermark (outline only) and a faint overlay of the patch would be seen (see Figure 2c);

(d) In the infrared light reflected from the back of the document, neither the watermark nor the patch overlay would be seen (see Figure 2d);

(e) In the light reflected in the visible spectrum, from the visible side of the document, one or more synthetic images would be seen, but not the watermark (or only a faint outline of the watermark) (see Figure 3a );

(f) In light reflected in the visible spectrum, from the back of the document, the watermark would appear dark (see Figure 3b);

(g) In transmitted light of the visible spectrum, from the visible side of the document, the combined image of the watermark and the one or more synthetic images would be seen (see figure 3c); and

(h) In the transmitted light of the visible spectrum, from the back of the document, the watermark (shield and number 30) would be seen in reverse with a patch color overlay, but not the projected synthetic images (see figure 3d).

As mentioned above, in addition to the at least partially overlying or underlying micro-optical device, one or more additional security features may be contained in the first and / or second region of the one or more watermarks or within the same). In one such embodiment, the watermark (s) do not contain one or more polymers or resinous materials within the first and / or second region. Additional security features are selected from the group of areas of highest fiber density in the form of recognizable or discernible signs, one or more color-imparting substances, and one or more second-level security features that are machine-detectable or machine-readable. a machine, as described above.

Reference is now made to methods or techniques for producing the first example embodiment in which a fibrous web with a film-like or sheet-like security element is aligned in the machine direction (MD) relative to one or more watermarks contained or formed on the sheet material.

The film-like or sheet-like security features can be embedded (when in the form of, for example, a security strip or thread) in a second layer of paper, or applied to a surface of the layer of branded paper. of water or second layer of paper (when in the form of, for example, thread or patch) using known procedures and techniques. For example, security features (with one or more adhesive layers) can be transferred to a surface of the watermarked paper layer or second layer as a transfer film using techniques including mechanical, chemical, thermal, and separation techniques. photoinduced. The concept of separating the desired components from a support substrate is known in the holographic foil transfer art, whereby a film with a release liner (i.e., a release liner) is provided with coatings (eg, optical) and adhesives, so that coatings and adhesives can be transferred to a final substrate with the application of heat and pressure. This approach is particularly useful in applications that require films with very thin cross-sectional thicknesses.

Activatable adhesives can be used to anchor or bond the film-like or sheet-like security elements on or within a surface of the fibrous sheet material. Suitable adhesives are not limited and include, but are not limited to, water, heat and / or pressure activated adhesives that are activated in the secondary drying section of the papermaking machine where temperatures range from 100 ° C and 160 ° C. These coatings can be applied in the form of solvent-based polymer solutions or aqueous solutions or dispersions. Suitable dispersions are selected from the group of acrylic resin dispersions, epoxy resin dispersions, natural latex dispersions, polyurethane resin dispersions, polyvinyl acetate resin dispersions, polyvinyl alcohol resin dispersions, urea formaldehyde resin dispersions , vinyl acetate resin dispersions, ethylene vinyl acetate resin dispersions, ethylene vinyl alcohol resin dispersions, polyester resin dispersions, and mixtures thereof. Machine direction alignment of security patches to watermarks contained or formed in the sheet material can be achieved by indexing the relative position of the watermark (s) on the equipment used to produce the watermark (s). water mark (s) on the sheet of paper. The position of the watermarks is continuously transmitted to the equipment used to apply the security patches to the surface of the paper. The marks or indices previously applied on the support film used to transport the patch (s) are used to control the speed of the carrier film and, therefore, the patch (s), ensuring, of this mode, the alignment of the water mark (s) with the patch (s).

The machine direction alignment of a security thread with watermarks contained or formed in the sheet material will now be described in conjunction with Figures 4 to 6.

In Figure 4, a Fourdrinier process for producing a single layer embodiment of the fibrous sheet material of the present invention is shown. In this process, an adhesive-coated security thread 20 (oriented in such a way that the visible side of the security thread and not the rear side covered with adhesive is a top layer) is guided along a tube 22 with a device variable speed feed 24 (e.g., a servo drive) and is pushed toward a surface of a partially consolidated advancing fibrous web 26 (e.g., a fibrous suspension containing between about 1 and about 10% in weight of starting material and between about 99 and about 90% by weight of water) to the wet end 28 of the papermachine after a watermark has been incorporated to the web 26 by a cylinder of Pressure roller 30. Here, the security thread 20 may be partially or completely placed over the watermark (ie, layered security features) on the surface of the web 26. As will be readily appreciated by those skilled in the art, the pressure roll cylinder 30 may be provided with raised and / or recessed areas on its surface, which may totally or partially overlap the area on the surface of the web 26 that will be occupied by thread 20.

It is observed that this embodiment of the method of the invention does not alter the distribution of fibers around the security thread applied on the surface, resulting in a distribution of fibers of higher density with a higher density and rigidity of the substrate that resists deformation, distortion and bending the security thread. As water continues to drain from web 26, fibers form around yarn 20 holding it in place on a front or top surface of web 26. As the wet end 28 exits, fibrous web 26 passes through the pressing, primary and secondary drying and calendering sections of the papermaking machine. While in the secondary drying section of the papermaking machine, web 26 is exposed to temperatures and / or pressures sufficient to activate the adhesive coating of the security thread, causing it to bond firmly to the thread in the material. fibrous laminate, with the security thread continuously exposed on a front or upper surface of the laminate partially or fully covering the formed water mark (s), while hidden from view on a rear or lower surface sheet material.

Directional machine alignment of the security thread 20 with the formed water mark (s) is achieved using conventional techniques commonly employed in the art. For example, and as best shown in Figure 4, an automatic alignment control system is used for a papermaking machine, which includes the variable speed security thread advance device 24, optical sensors 32a , 32b to follow alignment marks on pressure roll cylinder 30 and security thread 20, and a coding wheel 34 to control the speed of the paper being formed in the machine.

When the forming belt 26 moves through the wet end 28 of the paper machine, the alignment marks located on the pressure roll cylinder 30 and on the security thread 20 are continuously monitored by the optical sensors 32a, 32b, continuously determining / monitoring the position of the security thread 20 that is fed through the tube 22 and the advance device 24 and the position of the watermark relative to an edge of the forming band 26, while the speed of paper formation is controlled by means of the coding wheel 34. Signals are produced from the position and speed determinations. and the speed and position of the advance device 24 are regulated based on those signals so that the security thread 20 and the watermark are aligned along the machine direction of the web 26. In another embodiment In the method of the invention, shown in Figure 5, the adhesive-coated security thread 20 (again oriented so that the security thread and not the adhesive coating is a top layer) is guided through the advancement device variable speed 24 and by the optical sensor 32b and is then pushed towards a surface of the partially consolidated fibrous forming web 26 by the pressure roll 30 at the wet end 28 of the papermaking machine, incorporating the pressure roll 30 a watermark simultaneously or subsequently to the band 26. It is observed that, by means of this embodiment of the method of the invention, the fiber flows around the security thread, giving as a lower density fiber distribution resulted with reduced density and stiffness of the substrate under the yarn.

Similar to above, when the former band 26 moves through the wet end 28 of the paper machine, the alignment marks placed on the pressure roll cylinder 30 and on the security thread 20 are continuously controlled by the optical sensors 32a, 32b, thus continuously determining / controlling the position of the water mark (s) and the position of the security thread 20 applied to a surface of the band 26 relative to an edge of the forming belt 26, while the speed of the paper being formed is controlled by the coding wheel 34. Signals are produced from the position and speed determinations, and the speed and position of the advance device 24 are are adjusted based on those signals so that the security thread 20 and the water mark (s) are aligned along the machine direction 26.

A cylinder molding process for making a two-layer embodiment of the fibrous sheet material of the present invention is shown in Figure 6. In this process, which employs two cylinder paper machines 36a, 36b, connected to each other by a take-up felt 38, two webs of paper 40, 42 are simultaneously formed, compressed together in the area of the roller 44 and then fed seals in the pressing, drying and calendering sections of the papermaking machine. The resulting fibrous sheet material has the same physical characteristics as indicated above for sheet materials manufactured using a Fourdrinier process. As will be readily appreciated by those skilled in the art, although Figure 6 shows wet-tub type roll paper machines, dry-tub type roll paper machines can also be used to make the fibrous web of the present invention. .

The two-layer paper web 46, formed by the roll paper machines shown in Figure 6, has an adhesive-coated security thread 20 embedded and one or more watermarks formed on a surface thereof, with the thread 20 safety mark (s) and the water mark (s) fully visible from this surface. The water mark (s) are formed on the paper web 40 by the forming cylinder 48 and then the security thread 20 is integrated into the paper web directing the thread through the variable speed advance device 24 and passing the optical sensor 32b and then between the roller 50 and a surface of the paper web exiting the drum paper machine 36a. Here, the security thread 20 can be partially or completely placed over the watermark or marks on the surface of the paper web. The paper web 40 with the security thread 20 applied to the surface and the water mark (s) is then directed between the roller 44 and a surface of the second paper web 42 exiting the paper machine. cylinder 36b, where the two paper webs are compressed together. The second paper web 42 is homogeneous and serves to hide any irregularities in the formation of paper on a rear or bottom surface of the first paper web 40 that may have been caused by the presence of the yarn 20.

As mentioned above, the forming cylinder 48 may be provided with raised and / or recessed areas on its surface, which may totally or partially overlap the area contacted by the wire 20 during manufacture.

As in previous embodiments, the directional alignment of the machine between the security thread 20, the watermark or marks and the paper web 40 is achieved by means of the variable speed security thread advance device 24, optical sensors 32a , 32b for following alignment marks on the forming roll 48 and security thread 20, and a coding wheel 34 for tracking the speed of the paper being formed on the roll paper machine 36a.

Upon exiting the calendering section of any of the aforementioned papermaking machines, the fibrous sheet material of the invention can be rolled up and stored or fed directly into another machine (eg a printing machine) for further processing.

In a second exemplary embodiment, the security paper of the invention is a multilayer paper comprising:

a first layer of paper that has a reduced basis weight (e.g., between about 10 and about 50 g / m2) and includes one or more watermarks, each surface of the first layer of paper showing the top or front of the one or more watermarks or the bottom or back of it; and a second layer of paper having a reduced basis weight (e.g., between about 10 and about 50 g / m2) and optionally one or more through windows, the second layer of paper covering the surface of the first layer of paper that shows the top or front of the one or more watermarks or the surface that shows the bottom or back of the one or more watermarks.

In one such embodiment, the second layer of paper is windowed, the one or more through windows in the second layer of paper being aligned with the one or more watermarks. By way of this second exemplary embodiment, the use of two layers of paper and optionally one or more overlapping through windows allows for greater contrast between the one or more watermarks and the background.

In a third exemplary embodiment, one or more security features in the form of one or more color-imparting substances are contained within the first and / or second region of the one or more watermarks. The one or more color-imparting substances include both colorants and pigments (eg, pigments with an ultrafine particle size). As noted above, in this embodiment, the security sheet or document does not include one or more film-like or sheet-like security elements. The resulting watermarks are toned (i.e., color scheme or range of tones) in a different color or hue from the bulk region of the material surrounding the watermarks, which serves to increase their perception and strength to simulation.

Watermarks have traditionally been the same color as the paper substrate on which it is supported or inside it. These marks are formed by a localized variation in the thickness of the paper that varies the opacity of the paper, making the watermark visible in transmitted light or reflected light on a dark background.

A standard or prior art watermark is shown in Figure 7 against the same colored paper substrate. Here, only a marginal contrast is evident between the light and dark areas of the watermark, making the watermark more difficult to detect. For comparison, as also shown in Figure 7, the improved watermark of the present invention, which includes one or more color imparting substances in the form of one or more visible (colored) pigments (i.e., blue), has an enhanced quality in which the contrast between the light and dark areas in the watermark is significantly higher. Therefore, the public's attention is more easily focused on the invention watermark which increases the effectiveness of this security feature.

Another example embodiment of the present invention is shown in Figure 8. Here, the watermark of the invention contains a second-level security feature in the form of a UV-excitable substance in addition to one or more color-imparting substances. The watermark of the invention not only shows a marked contrast between light and dark areas in transmitted light, but also contains a substance that can be excited by UV radiation, it also demonstrates a UV response tonality that is difficult to reproduce, making the watermarking even more resistant to counterfeiting. Referring now to Figure 9, in an example embodiment in which the security sheet or document is a paper security document, the inventive method of manufacturing the security document involves making a continuous roll of branded paper. of water 52 in a papermaking machine 54 (Figure 9a), some watermarks or watermark regions 56 that are repeated along the paper (Figure 9b), each presenting lower grammage areas (ie i.e. first regions) and heavier areas (i.e. second regions), to provide lighter and darker areas in the watermark regions 56, the procedure comprising:

applying a colored solution 58 comprising substances that impart color to the plurality of watermark regions 56 on one side of the continuous roll of paper while applying vacuum to an opposite side of the paper to pull the colored solution applied to the paper,

wherein the upper weight areas of the watermark regions 56 contain more color-imparting substances while the lower-weight areas contain fewer color-imparting substances, thus providing the hue of the watermark regions in one color or shade different from that of the bulk regions of the paper surrounding the plurality of repeating watermark regions along its length.

As indicated above, the watermarks are formed by well known techniques, for example, on a cylinder mold paper machine or a roll paper machine. Fourdrinier (using a pressure roller). A variety of fiber types can be used to make the paper, including synthetic or natural fibers or a mixture of both.

The "colored solution" used to impart hue to the watermarks of the present invention comprises the one or more of the aforementioned color imparting substances, including both colorants and pigments (eg, ultrafine particle size pigments).

After forming watermarks on the paper machine 54, the colored solution 58 is applied locally to the watermark regions 56 of the paper while the paper is still wet and on a forming wire and before any pressing occurs. damp. The colored solution can be applied to the continuous roll of watermarked paper 52 using a low volume intermittent shower with nozzles 60 aligned with the watermarked regions of the paper. The colored solution is introduced onto the paper web using one or more vacuum boxes 62. Although two vacuum boxes are shown in Figure 9b, one or more vacuum boxes may be used in practicing the process of the invention.

In a fourth example embodiment, to be referred to as a "transparent" watermark embodiment, one or more polymers or resinous materials are contained within the first region (s) and optionally the second ( s) zone (s) of one or more watermarks. As noted above, the security sheet or document in this exemplary embodiment does not include one or more film-like or sheet-like security elements. The first and / or second region in this embodiment may also contain one or more security features selected from the group of areas of higher fiber density in the form of recognizable or discernible markings, one or more color-imparting substances, and one or more features. Second-level security features that are machine-detectable or machine-readable, as described above.

The transparent watermark embodiment of the present invention provides an easily recognizable public safety feature for first-level authentication. The watermark (s) of the invention, which may be a feature on paper, allows authentication by its transmission properties. The inclusion of such a translucent or transparent region within a security document (eg, banknote) cannot be replicated with subsequent scanning, image analysis, and digital reproduction techniques.

In an exemplary embodiment, the clear water mark (s) of the invention is (are) obtained as part of the papermaking process during sheet formation in the wet state. For example, a paper web is produced continuously on a Fourdrinier papermaking machine. The paper is deposited from a head box onto a continuously moving wire mesh. The water from the paper drains through the wire mesh exiting a wet fiber mat without water.

The transparent water mark (s) of the invention are formed by first forming by removing paper material from selected areas of the fiber mat with a resulting reduction in fiber density (see Figure 10 ). This can be done using conventional techniques, such as pressure roll (or barrel) technology. Selected areas with lower fiber density (i.e., the first regions) have reduced opacity compared to other areas of the watermarks (i.e., the second regions) and other areas of the fiber mat (i.e. the base sheet), although not transparent. Next, the first and optionally the second region of the watermark (s) are treated with one or more polymers or resinous materials selected for a final refractive index that closely matches cellulose (e.g., curable by UV rays, electron beam curable or heat curable polymer or resinous material).

The first and second regions can be treated with the one or more polymers or resinous materials in the papermaking machine, in an offline web process, such as rewinding or winding, in a dedicated offline web process before cut from the sheet, or into individual sheets.

The one or more polymers or resinous materials, which saturate the paper in the first and optionally in the second region of the water mark (s) (replacing the air in the interstices between the fibers), optionally can (n) applied in a pattern over these areas, and may further cure through radiation, thermal / catalytic or oxidative means.

As best shown in Figures 11a, b, transmission of visible light through the resulting translucent or transparent water mark (s) is now possible. As a result, the printed material viewed under the transparent watermark (s) is clearly legible.

The choice of a polymer or resinous material (s) of appropriate modulus may also allow embossing applications to be made in the translucent or transparent areas, for example, prior to printing, or during an intaglio printing process.

The transparent water mark (s) of the invention may also include one or more features within its perimeter selected from the group of areas of higher fiber density in the form of recognizable or discernible marks, a or more color imparting substances and one or more second level security features that are machine detectable or machine readable, as described above.

These features in the form of, for example, fibers or planchettes can be added by random addition to the papermaking composition, or selectively placed in line at the position of the transparent security element. Additionally, or alternatively, such inclusions could be concentrated in specific cross directional areas of the paper.

In a fifth exemplary embodiment, the security foil or document of the invention is a single layer paper comprising:

a layer of paper that includes one or more watermarks; and

one or more transparent or translucent areas in the paper layer surrounding each of the one or more watermarks, thereby weaving together and thus enhancing the visual perception of the watermark (s).

Such raster-like areas can be formed on the watermarked paper layer by treating the areas surrounding each watermark with one or more transparent polymers or resinous materials, such as a UV-curable, UV-curable polymer or resinous material. electronic beam or thermally curable.

These weft-like areas can be treated with the transparent material (s) on the paper machine, in an off-line web process such as rewinding or winding, in an off-web web process. Dedicated line prior to sheet cutting, or into individual sheets.

Transparent materials saturate the paper in the applied areas, replacing the air in the interstices between the fibers. This (these) material (s) may be curable (s) or non-curable (s). The treated areas of the watermarked paper layer allow the transmission of visible light, weaving and enhancing the visual perception of watermark (s).

Although various embodiments of the present invention have been described above, it should be understood that these have been presented by way of example only, and not limitation. Therefore, the breadth and scope of the present invention should not be limited by any of the exemplary embodiments.

Other embodiments comprising the invention are mentioned below:

REALIZATIONS

Embodiment 1. Security foil or document having one or more watermarks or enhanced watermark designs, comprising:

a fibrous sheet material that includes one or more watermarks or watermark designs, wherein each watermark design has one or more first regions with reduced fiber densities relative to surrounding regions of the fibrous sheet material and one or more plus second regions with similar or higher fiber densities relative to surrounding regions of the sheet material, and wherein each watermark pattern has a top or front and a bottom or back; and

means for enhancing the one or more watermarks or watermark designs by making them visually enhanced, detectable or machine readable, or both, said means comprising:

one or more transparent or translucent areas surrounding each of the one or more watermark designs. Embodiment 2: The security sheet or document of Embodiment 1, which is a multilayer paper comprising:

a first layer of paper that has a reduced basis weight (e.g., between about 10 and about 50 grams per square meter and that includes one or more watermarks or watermark designs, showing each surface of the first layer of paper the top or front of the one or more watermarks or their bottom or back; and

means for enhancing the one or more watermarks or watermark designs in the form of a second layer of paper having a reduced basis weight of between about 10 and about 50 grams per square meter and optionally one or more through windows, covering the second paper layer the surface of the first paper layer showing the top or front of the one or more watermark designs or the surface showing the bottom or back of the one or more watermark designs.

Claims (2)

1. Security foil or document (10) that has one or more watermarks (14) or enhanced watermark designs, comprising: a fibrous sheet material that includes one or more watermarks or watermark designs, wherein each watermark design has one or more first regions (18) with reduced fiber densities relative to surrounding regions of the fibrous sheet material and one or more second regions (16) with similar or greater fiber densities relative to surrounding regions of the sheet material, and wherein each watermark pattern has a top or front and a bottom or back; and means for enhancing the one or more watermarks or watermark designs by making them visually enhanced, detectable or machine readable, or both, said means being characterized by the fact that they comprise: one or more transparent or translucent areas surrounding each of the one or more watermark designs. 2. Security foil or document (10) according to claim 1, which is a multilayer paper comprising: a first layer of paper having a reduced basis weight of between about 10 and about 50 grams per square meter and including one or more watermarks (14) or watermark designs, showing each surface of the first layer of paper the top or front of the one or more watermark designs or its bottom or back; and means for enhancing the one or more watermarks or watermark designs in the form of a second layer of paper having a reduced basis weight of between about 10 and about 50 grams per square meter and optionally one or more through windows, covering the second paper layer the surface of the first paper layer showing the top or front of the one or more watermark designs or the surface showing the bottom or back of the one or more watermark designs.