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, CFA to CFH) consisting of printed fields of each relevant printing ink that is printed in the effective printed region (EF). The color control fields (CF, CFA to CFH) 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 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, CFA to CFH) consisting of printed fields of each relevant printing ink that is printed in the effective printed region (EF). The color control fields (CE, CFA to CFH) 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 sheet-fed stamping press (10*) comprising a foil application unit (2*) designed to allow transfer or lamination of foil material onto successive sheets (S), which foil material is fed to the foil application unit (2*) in the form of a foil carrier (FC) supplied by means of a foil feeding system (3). The foil application unit (2*) comprises a stamping cylinder (21) with at least one circumferential stamping section (210) provided on a circumference of the stamping cylinder (21) and comprising successive stamping segments (211*; 211**) distributed one after the other about the circumference of the stamping cylinder (21), the stamping cylinder (21) also acting as sheet-transporting cylinder and comprising multiple sheet holding units (21a) distributed about the circumference of the stamping cylinder (21) and designed to hold successive sheets (S) against the circumference of the stamping cylinder (21). The foil application unit (2*) further comprises a plurality of counter-pressure units (25) distributed about a portion of the circumference of the stamping cylinder (21) and designed to press the successive sheets (S) and the foil carrier (FC) against an outer surface of the stamping segments (211*; 211**), the foil carrier (FC) being supplied by the foil feeding system (3) between the sheets (S) and the stamping segments (211*; 211**). Each counter-pressure unit (25) is designed as a cylinder unit (250, 255) provided with at least one circumferential pressing element (255) positioned to cooperate with the circumferential stamping section (210) of the stamping cylinder (21), and the counter-pressure units (25) are driven into rotation by means of at least one dedicated drive (26).
Abstract:
There is described an inking apparatus of a printing press, in particular an offset or letterpress printing press, comprising at least one ink duct (11, 12) with an ink supply roller (13, 14), an ink roller train (30) comprising at least one inking roller (31) which receives ink from the at least one ink duct (11, 12), and at least one vibrator roller (15, 16) interposed between the ink supply roller (13, 4) and the inking roller (31), which vibrator roller (15, 16) is swung back and forth between the ink supply roller (13, 14) and the inking roller (31) and intermittently transfers ink from the ink supply roller (13, 14) to the inking roller (31). A circumference of the vibrator roller (15, 16) exhibits an ink-transfer 10 structure (15a, 16a) which reflects a desired inking profile of a printing plate to be inked by the inking apparatus and is designed to modulate a quantity of ink transferred by the vibrator roller (15, 16). The ink-transfer structure (15a, 16a) on the circumference of the vibrator roller (15, 16) is subdivided, in a circumferential direction (y) of the vibrator roller (15, 16), into an integer number 1 (r) of individual ink-transfer portions (15b, 16b) that are repeated with a determined circumferential period (Δy) in the circumferential direction (y), each individual ink-transfer portion (15b, 16b) reflecting the desired inking profile of the printing plate to be inked by the inking apparatus. A contact length (CL) over which the vibrator roller (15, 16) runs in contact with the ink supply roller (13, 204) is equivalent to the determined circumferential period (Δy) of the individual ink-transfer portions (15b, 16b) or to an integer multiple of the determined circumferential period (Δy) of the individual ink-transfer portions (15b, 16b).
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 an intaglio printing press (1; 1*) comprising a plate cylinder (8) carrying one or more intaglio printing plates, the plate cylinder (8) receiving ink from an inking system (9, 20, 23; 20*, 23*) having a plurality of chablon cylinders (23; 23*) transferring ink directly or indirectly onto the plate cylinder (8), the intaglio printing press (1; 1*) comprising an adjustment system acting on the chablon cylinders (23; 23*) in order to compensate elongation of the one or more intaglio printing plates. The adjustment system comprises, for each chablon cylinder (23; 23*), an adjustable drive unit, which adjustable drive unit (25) is interposed between the chablon cylinder (23; 23*) acting as a rotating output body of the adjustable drive unit (25) and a driving gear (100) acting as a rotating input body of the adjustable drive unit (25). The adjustable drive unit (25) is designed to allow selected adjustment of a rotational speed of the chablon cylinder (23; 23*) with respect to a rotational speed of the driving gear (100). In an adjusting state of the adjustable drive unit (25), driving into rotation of the chablon cylinder (23; 23*) is adjusted over each revolution of the chablon cylinder (23; 23*) by means of an adjustment motor (300) of the adjustable drive unit (25). In a non-adjusting state of the adjustable drive unit (25), the adjustment motor (300) is inoperative and driving into rotation of the chablon cylinder (23; 23*) is performed exclusively mechanically via the adjustable drive unit (25), the chablon cylinder (23; 23*) rotating at a same rotational speed as the driving gear (100).
Abstract:
There is described a method of creating a transparent window (W*) in a security, especially paper, substrate (1) for security printing applications, the method comprising the steps of (i) providing a security substrate (1), (ii) forming an opening (10*) into and through the security substrate (1), and (iii) filling the opening (10*) with transparent material (2) thereby forming the transparent window (W*). The filling of the opening (10*) with the transparent material (2) is carried out in a state where the opening (10*) is open on both sides of the security substrate (1) and extends through the security substrate (1), the filling of the opening (10*) including (10 the application of a first side (I) of the security substrate (1) against a supporting surface (21A) of a supporting member (20′, 21) in such a way as to block one side of the opening (10*), while the transparent material (2) is applied inside the opening (10*) from the other side (II) of the security substrate (1). Advantageously, the method further comprises the step of forming a field of lenses (L) on one side of the transparent window (W*), in particular by replicating the field of lenses (L) directly into the transparent material (2) filling the opening (10*). Also described is a suitable device designed to fill the opening (10*) with the transparent material (2).
Abstract:
There is described an intaglio printing press (1; 1 *) comprising a plate cylinder (8) carrying one or more intaglio printing plates, the plate cylinder (8) receiving ink from an inking system (9, 20, 23; 20*, 23*) having a plurality of chablon cylinders (23; 23*) transferring ink directly or indirectly onto the plate cylinder (8), the intaglio printing press (1; 1 *) comprising an adjustment system acting on the chablon cylinders (23; 23*) in order to compensate elongation of the one or more intaglio printing plates. The adjustment system comprises, for each chablon cylinder (23; 23*), an adjustable drive unit, which adjustable drive unit (25) is interposed between the chablon cylinder (23; 23*) acting as a rotating output body of the adjustable drive unit (25) and a driving gear (100) acting as a rotating input body of the adjustable drive unit (25). The adjustable drive unit (25) is designed to allow selected adjustment of a rotational speed of the chablon cylinder (23; 23*) with respect to a rotational speed of the driving gear (100). In an adjusting state of the adjustable drive unit (25), driving into rotation of the chablon cylinder (23; 23*) is adjusted over each revolution of the chablon cylinder (23; 23*) by means of an adjustment motor (300) of the adjustable drive unit (25). In a non-adjusting state of the adjustable drive unit (25), the adjustment motor (300) is inoperative and driving into rotation of the chablon cylinder (23; 23*) is performed exclusively mechanically via the adjustable drive unit (25), the chablon cylinder (23; 23*) rotating at a same rotational speed as the driving gear (100).
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.