A can inspection device includes a rotation device rotating cans, an imaging device taking images of rotating cans, and an image processor processing taken images. The imaging device includes a first camera taking an image of an entire can and a second camera taking an image of an opening-side end portion of the can. The image processor includes an image inspection means for inspecting whether printing is performed properly as compared with a master image by using the image taken by the first camera, a density measurement means for measuring densities in designated positions for respective colors by using the image taken by the first camera, and a printing misalignment value measurement means for measuring misalignment values with respect to set positions of printing misalignment inspection marks printed on the opening-side end portion of the can for respective colors by using the image taken by the second camera.

A method for setting up a lithographic printing press is provided which reduces the make-ready time of on-press developable printing plates so that less copies are wasted. The method uses an ink boost at the startup of the press by presetting the inking system to a configuration whereby the amount of ink supplied to the plate is different from the amount prescribed by standard printing conditions. The ink boost can be positive or negative and can be made dependent on the difference in the image coverage between plates used in successive print jobs or on different paper types used in successive print jobs.

The ink in a printing press is controlled during a printing process in which an opaque ink is printed onto a substrate in a first printing unit and a transparent ink is printed onto the opaque ink in a second printing unit. An optical density value of the transparent ink is ascertained by a detection device for the transparent ink printed onto the previously printed opaque ink. A film thickness of the transparent ink is set at the second printing unit by a control unit that detects the optical density value of the transparent ink as a function of the film thickness of the opaque ink, or as a function of an optical density value of the opaque ink, so that the optical density value of the transparent ink corresponds to a target value set at the control unit for the transparent ink, and considering a transparent ink tolerance range.

The present disclosure relates to systems and processes for inspecting and evaluating qualities of printed regions on substrates, wherein the systems and methods may be configured to eliminate subjective aspects relating to human involvement in performing visual checks when evaluating print quality. The systems may include one or more communication networks connecting one or more sensors with an analyzer. In operation, ink is applied to a substrate to create at least one printed region, and the sensors are configured to inspect the printed region. The sensors may be configured to communicate measurements and/or images to the analyzer. And the analyzer may then calculate one or more quality subscores based on respective measurements and/or images. In turn, a full print quality score may be calculated based on one or more of the quality subscores. The analyzer may then execute a control action based on the full print quality score.

The invention relates to a method for ink control in a printing press, wherein, during an ongoing printing process, an opaque ink (02) is printed onto a print substrate (01) in a first printing unit (06), and subsequently a transparent printing ink (03) is printed onto the opaque ink (02) in a second printing unit (07), at least one actual value of the optical density of the opaque ink (02) being ascertained by a first detection device (08) for this opaque ink (02) printed onto the print substrate (01), a film thickness of this opaque ink (02) to be applied onto the print substrate (01) being set at the relevant printing unit (06) by a control unit (11) detecting the at least one actual value of the optical density of this opaque ink (02), as a function of a previously ascertained value of the optical density of the surface of the unprinted print substrate (01), in such a way that the at least one actual value of the optical density of this opaque ink (02) detected by the first detection device (08) corresponds to a target value set at this control unit (11) for this opaque ink (02), taking a tolerance range defined in the control unit (11) for this opaque ink (02) into consideration; at least one actual value of the optical density of this printing ink (03) being ascertained by a second detection device (09) for the printing ink (03) printed onto the previously printed opaque ink (02); and a film thickness of this printing ink (03) to be applied onto the opaque ink (02) being set at the printing unit (07) printing this printing ink (03) by the control unit (11) which also detects the at least one actual value of the optical density of this printing ink (03), as a function of the film thickness of the opaque ink (02) previously applied to the print substrate (01) or as a function of the actual value of the optical density of this opaque ink (02), in such a way that the at least one actual value of the optical density of this printing ink (03) detected by the second detection device (09) corresponds to a target value set at the control unit (11) for this printing ink (03), taking a tolerance range defined in the control unit (11) for this printing ink (03) into consideration.

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.sub.A to CF.sub.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.sub.A to CF.sub.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).

Formation of a plurality of wear visibility grooves 10 has been focused. An elastic roller includes: an inner layer side elastic material 4; a coating layer 5 disposed on an outer periphery of the inner layer side elastic material 4, the coating layer configured to make contact with the belt-shaped member; and a plurality of wear visibility grooves 10 (11, 12, 13) formed on an inner side of the coating layer 5 and formed on a surface of the inner layer side elastic material 4 in a circumferential direction, the plurality of wear visibility grooves being successively formed in an axial direction of the roller shaft, wherein at least two grooves of the plurality of wear visibility grooves have different heights, and filler is filled in the plurality of wear visibility grooves 10, the filler having a color different from that of the inner layer side elastic material 4 and different from that of the coating layer 5, and material of the filler is the same as that of the coating layer 5.

A system is disclosed. The system at least one physical memory device to store ink deposition curve compute logic and one or more processors coupled with the at least one physical memory device, to execute the ink deposition curve compute logic to receive a histogram for each of a plurality of color planes, receive ink measurement data for each of the plurality of color planes, compute ink deposition curve data for each of the plurality of color planes based on the histograms and the ink measurement data and transmit the ink deposition curve data.

A method for the automated generation of reference color values for color control purposes in a printing machine by using a computer includes, within a process of setting up the printing machine for a print job, initially carrying out printing operations and using a spectrophotometer to determine coloration values for every process color used in the print job. For every process color that is used in the print job, the computer automatically selects that coloration value of a process color that has the smallest deviation from a color set point that has been established at the beginning of the job and saves this coloration value as a new reference value for this process color.

This document discloses a system to dispense a precise and continuous amount of ink for a large printing press. The dispensing system can be judiciously combined into a more elaborate dispensing system that uses two chambers with ink having a different density to dispense ink with a precise, adjustable and stable ink density. The dispensing system can be used to compensate the drifts in quality observed in presses when the speed, or any environmentable parameters vary.