Abstract:
There is described a color control pattern (CP) for the optical measurement of colors printed on a sheet or web substrate (S) by means of a multicolor printing press, especially by means of a multicolor security printing press, which substrate (S) exhibits an effective printed region (EF) having a multicolor printed image comprising a plurality of juxtaposed colored areas (A- H) printed with a corresponding plurality of printing inks of different colors, wherein the color control pattern (CP) is located in a margin portion (Im) of the substrate (S) next to the effective printed region (EF). The color control pattern (CP) comprises one or more color control strips (a-d) extending transversely to a direction of transport (T) of the substrate (S), each color control strip (a-d) comprising a plurality of distinct color control fields (CF, CF A to CF H ) consisting of printed fields of each relevant printing ink that is printed in the effective printed region (EF). The color control fields (CF, CF A to CF H ) are coordinated to actual application of the relevant printing inks in the effective printed region (EF) and are positioned transversely to the direction of transport (T) of the substrate (S) at locations corresponding to actual positions where the relevant printing inks are applied in the effective printed region (EF).
Abstract:
There is described a method of manufacturing a security article, said method comprising the steps of: introducing into an offset printing device a transparent film comprising a non-fibrous substrate layer of regenerated cellulose; and disposing printed information on at least a portion of said transparent film by an offset printing step, wherein said transparent film introduced into said offset printing device further comprises an ink-receptive layer on at least one surface of said substrate layer.
Abstract:
There is described a printed security element (10; 10*; 10**) comprising a rainbow feature (15; 15*; 15**) exhibiting, at least in part, a gradual transition from a first colour (C1) to a second colour (C2) distinct from the first colour (C1), wherein the rainbow feature (15; 15*; 15**) extends over a colour-gradient area (A) of the printed security element (10; 10*; 10**) where first and second printed patterns (P1, P2) are partly superimposed or juxtaposed, each of the first and second printed patterns (P1, P2) comprising a first, respectively second set of linear or curvilinear elements (20, 30; 20*, 30*), the first and second printed patterns (P1, P2) being printed in register one with the other by means of two distinct printing plates (PP1, PP2) so that the first and second sets of linear or curvilinear elements (20, 30; 20*, 30*) are partly superimposed or juxtaposed in the colour-gradient area (A) and thereby generate the rainbow feature (15; 15*; 15**), the first printed pattern (P1) exhibiting the first colour (C1) and being printed by means of a first printing plate (PP1) and the second printed pattern (P2) exhibiting the second colour (C2) and being printed by means of a second printing plate (PP2), where at least the first or second printed pattern (P1; P2) exhibits, in the colour-gradient area (A), a modulation of line width or line structure such as to cause, when superimposed or juxtaposed with the other printed pattern (P2; P1), a gradual transition from the first colour (C1) to the second colour (C2), wherein, in the colour-gradient area (A), the second printed pattern (P2) is printed on top of the first printed pattern (P1) and wherein the second colour (C2) is darker than the first colour (C1). Also described is a method of producing the aforementioned printed security element.
Abstract:
There is described a combined printing press (10; 10*) for the production of security documents, in particular banknotes, comprising a screen printing group (2; 2*) and an intaglio printing group (3)adapted to process substrates in the form of individual sheets or successive portions of a continuous web. The screen printing group (2; 2*) is located upstream of the intaglio printing group (3) and comprises at least one screen printing unit (20; 20*) designed to print a pattern of optically-variable ink onto one side of the substrates, which optically- variable ink contains flakes that can be oriented by means of a magnetic field. The screen printing group (2; 2*) further comprises a magnetic unit (24; 24*) located downstream of the screen printing unit (20; 20*), which magnetic unit is designed to magnetically induce an optically-variable effect in the pattern of optically-variable ink applied by the screen printing unit (20; 20*). The screen printing group (2; 2*) further comprises at least one drying/curing unit (25, 28; 25*, 28*) designed to dry/cure the pattern of optically-variable ink in which the optically-variable effect has been induced by the magnetic unit (24), prior to transfer of the substrates to the intaglio printing group (3).
Abstract:
There is described a printed security feature (1) provided onto a printable substrate, which security feature includes a printed area (100) consisting of a multiplicity of adjacent rectilinear and/or curvilinear elements (110, 120) printed with a given spatial frequency. The rectilinear and/or curvilinear elements are printed with at least first and second inks which exhibit the same or substantially the same optical appearance when illuminated with visible white light, such that the security feature produces a first graphical representation when illuminated with visible white light, at least the first ink being an ink which responds to non- visible light excitation by producing a characteristic optical response differentiating the first ink from the second ink. The security feature produces a second graphical representation when illuminated with non-visible light, which second graphical representation exhibits a distinctive two-dimensional graphic element (B) which is revealed only when the security feature is illuminated with non-visible light. Inside boundaries (160) of the distinctive two-dimensional graphic element, a part (P3) of the rectilinear and/or curvilinear elements is printed with a combination of the first and second inks, the rectilinear and/or curvilinear elements being subdivided, within that part, into first and second juxtaposed sections (110a, 110b, 120a, 120b) which are respectively printed with the first ink and with the second ink. Outside the boundaries of the distinctive two-dimensional graphic element, portions (P1, P2) of the rectilinear and/or curvilinear elements are printed with only one of the at least first and second inks. The at least first and second inks are printed in register one with respect to the other so that the boundaries of the distinctive two-dimensional graphic element are not visible when the security feature is illuminated with visible white light and the distinctive two-dimensional graphic element only becomes visible when the security feature is illuminated with non-visible light.
Abstract:
There is described a method of creating a transparent polymer window (W) with a field of lenses (L) in a security paper substrate (1), the method comprising the steps of (i) providing a security paper substrate (1), (ii) forming an opening (10) into the security paper substrate (1), (iii) laminating a transparent film (5; 5*) onto a first side (I) of the security paper substrate (1) in such a way as to close the opening (10) at one end, and (iv) filling the opening (10) with transparent polymer material (2). In one embodiment, the transparent film (5) comprises a field of lenses (L) and is laminated onto the first side (I) of the security paper substrate (1) in such a way as to form lenses (L) on the first side (I) of the security paper substrate (1) in register with the opening (10). In another embodiment, the field of lenses (L) is replicated into the transparent polymer material (2) applied in the opening (10) in such a way as to form lenses (L) on a second side (II) of the security paper substrate (1), opposite to the first side (I), in register with the opening (10). Also described is a device designed to fill the opening (10) formed into the security paper substrate (1) with the transparent polymer material (2) and a processing machine comprising the same.
Abstract:
There is described an intaglio printing plate coating apparatus (1) comprising a vacuum chamber (3) having an inner space (30) adapted to receive at least one intaglio printing plate (10) to be coated, a vacuum system (4) coupled to the vacuum chamber (3) adapted to create vacuum in the inner space (30) of the vacuum chamber (3), and a physical vapour deposition (PVD) system (5) adapted to perform deposition of wear-resistant coating material under vacuum onto an engraved surface (10a) of the intaglio printing plate (10), which physical vapour deposition system (5) includes at least one coating material target (51, 52) comprising a source of the wear-resistant coating material to be deposited onto the engraved surface (10a) of the intaglio printing plate (10). The vacuum chamber (3) is arranged so that the intaglio printing plate (10) to be coated sits substantially vertically in the inner space (30) of the vacuum chamber (3) with its engraved surface (10a) facing the at least one coating material target (51, 52). The intaglio printing plate coating apparatus (1) further comprises a movable carrier (6) located within the inner space (30) of the vacuum chamber (3) and adapted to support and cyclically move the intaglio printing plate (10) in front of and past the at least one coating material target (51, 52).
Abstract:
There is described a substrate (S) for security documents, such as banknotes, comprising one or more paper layers (11, 12) and a polymer layer (20) which is made to adhere to a side of at least one of the paper layers (11, 12), which polymer layer (20) is substantially transparent in at least one region of the substrate (S) which is not covered by the paper layer or layers (11, 12) so as to form a substantially transparent window (W) in the substrate (S) which is formed and closed by the polymer layer (20). The polymer layer (20) exhibits in the region of the window (W) a thickness (T) which is greater than a thickness (t) of the polymer layer (20) outside of the region of the window (W). The thickness (T) of the polymer layer (20) in the region of the window (W) is substantially equal to the added thickness of the paper layer or layers (11, 12) and of the polymer layer (20) outside of the region of the window (W) so that the substrate (S) exhibits a substantially uniform and constant thickness (T). The substrate (S) further comprises a micro-optical structure (30), in particular a lens structure, which is disposed in the region of the window (W) on at least one side of the polymer layer (20).
Abstract:
A method of authenticating security documents and a mobile device, especially a smartphone, programmed to carry out the method, based on an analysis of features which are produced by intaglio printing, which analysis involves a decomposition of sample images of a candidate document to be authenticated based on Wavelets, each sample image being digitally processed by performing a Wavelet transform of the sample image in order to derive a set of classification features. The method is based on an adaptive approach, which includes the following steps : - prior to carrying out the Wavelet transform, defining a categorization map containing local information about different intaglio line structures that are found on the security documents; - carrying out a Wavelet selection amongst a pool of Wavelet types based on the categorization map; and - performing the Wavelet transform of the sample image on the basis of the selected Wavelet.
Abstract:
There is described an intaglio printing press comprising a plate cylinder (8) carrying one or more intaglio printing plates (8c) and an impression cylinder (7) cooperating with the plate cylinder (8), a printing nip being formed between the plate cylinder (8) and the impression cylinder (7). The plate cylinder (8) and the impression cylinder (7) each comprise one or more cylinder pits (8a, 7a) and a corresponding number of cylinder segments (8b, 7b), the plate cylinder (8) and the impression cylinder (7) being in rolling contact with one another during printing operations along their respective cylinder segments (8a, 7b) when no cylinder pits (8a, 7a) are present at the printing nip. The intaglio printing press further comprises a monitoring system (150) designed to monitor a rolling condition of the impression cylinder (7) with respect to the plate cylinder (8) and to provide an indication as to whether or not the rolling condition corresponds to a desired rolling condition, the desired rolling condition being a rolling condition corresponding to true rolling of the impression cylinder (7) with respect to the plate cylinder (8) where no slippage occurs between a circumferential surface of the impression cylinder (7) and a circumferential surface of the plate cylinder (8). Also described is a method of monitoring operation of an intaglio printing press.