Abstract: A support material toner particle for use in xerographic additive manufacturing includes a polyvinyl alcohol (PVA) polymer and blend-additives including a chitosan and a polyvinylpyrrolidone (PVP), the amount of blend-additives is selected to adjust the Tg of the PVA polymer to be within about 1° C. to about 20° C. of a desired build material toner Tg. A xerographic toner system includes a build toner material and a support toner material, the support toner material includes a polyvinyl alcohol (PVA) polymer and blend-additives including a chitosan and a polyvinylpyrrolidone (PVP), the amount of blend-additives is selected to adjust the Tg of the PVA polymer to be within about 1° C. to about 20° C. of the build material toner Tg. A method of making a support toner material includes blending polyvinyl alcohol with blend additives including a chitosan and polyvinylpyrrolidone and forming support toner particles after the blending step.

Abstract: A 3-D printer includes a development station positioned to electrostatically transfer layers of material to an intermediate transfer surface, and a transfuse station adjacent the intermediate transfer surface. The transfuse station is positioned to receive the layers as the intermediate transfer surface moves past the transfuse station. Also, a platen is included that moves relative to the intermediate transfer surface. The intermediate transfer surface transfers a layer of the material to the platen each time the platen contacts one of the layers on the intermediate transfer surface at the transfuse station to successively form a freestanding stack of the layers on the platen. A curing station is positioned to apply ultraviolet light to each layer, after each layer is transferred from the transfuse station to the platen. The curing station selectively applies the ultraviolet light to crosslink polymers only in a portion of the material within the layer.

Abstract: 3-D printing transfers build material and support from an intermediate transfer belt (ITB) to a platen. The build material is the same as the support material, except that the build material includes a photoinitiator and the support material does not. The platen moves to make contact with the ITB, and the ITB transfers successive layers of build material and support material each time the platen contacts the ITB. The platen and a portion of the ITB that is adjacent the platen are heated prior to the platen contacting the ITB, and the same is exposed so as to crosslink polymers of build material, without crosslinking polymers of support material. The polymers of build material being crosslinked and the polymers of support material not being crosslinked makes the support material selectively soluble in a solvent.

Abstract: 3-D printers include a transfuse station having at least one roller on one side of an ITB supporting the ITB, and a transmission device on the same side of the ITB. A charge neutralizer is included on a second side of the intermediate transfer surface. The charge neutralizer outputs an opposite charge to neutralize existing static charge on a layer of the build material and the support material on the ITB, before the layer reaches the transfer station. Additionally, the intermediate transfer surface transfers the layer to a platen each time the platen contacts the second side of the intermediate transfer surface, at the transfer station, to successively form layers of the build material and the support material on the platen. Also, the transmission device outputs acoustic waves to cause the layer to move from the intermediate transfer surface to the platen, or to the layers on the platen.

Abstract: A method of spatially and spectrally calibrating a spectrophotometer including: a) emitting a white light illumination output from a full width illumination source; b) illuminating a test patch with the white light illumination output; c) reflecting a portion of the white light illumination output from the test patch to form a white light reflected illumination output; d) receiving the white light reflected illumination output at first, second and third rows of photosensitive elements to form a first calibration data set; e) emitting a cyan light illumination output from the full width illumination source; f) illuminating the test patch with the cyan light illumination output; g) reflecting a portion of the cyan light illumination output from the test patch to form a cyan light reflected illumination output; and, h) receiving the cyan light reflected illumination output at the second and third rows of photosensitive elements to form a second calibration data set.

Abstract: A three-dimensional object printer generates image data of an object being formed in the printer with an optical sensor and identifies the heights of object features above a substrate on which the object is being formed. A controller operates one or more actuators to move the optical sensor at a plurality of distances above the object to generate image data of the object at a plurality of heights above the object. The controller identifies the distances of the features of the object with reference to the image data generated by the optical sensor and the focal length of the optical sensor.

Abstract: Provided is a system for providing spectral analysis with a spectrophotometer. The system includes an illuminator positioned adjacent to a carrier having a surface; a linear sensor positioned adjacent to the carrier; and a micropatterned optical filter is positioned between the linear sensor and the carrier. The illuminator is configured to emit light at a material disposed over the surface. The linear sensor is configured to receive the light from the illuminator.

Abstract: When performing a printing operation, methods and devices automatically increase a marking material quantity setting when an excessive speed variation condition of a transfer surface is present and an excessive background marking condition is absent. Alternatively, the methods and devices automatically increase tension of the transfer surface and decrease a marking material quantity setting when the excessive speed variation condition is present and the excessive background marking condition is also present. Otherwise, these methods and devices automatically provide a message on the graphic user interface of a printing device when the excessive speed variation condition is present, the marking material quantity setting is at a marking material quantity maximum setting, and the tension of the transfer surface is at a tension maximum. The message provides instructions to use a different type media or initiate a service call.

Abstract: When performing a printing operation, methods and devices automatically increase a marking material quantity setting when an excessive speed variation condition of a transfer surface is present and an excessive background marking condition is absent. Alternatively, the methods and devices automatically increase tension of the transfer surface and decrease a marking material quantity setting when the excessive speed variation condition is present and the excessive background marking condition is also present. Otherwise, these methods and devices automatically provide a message on the graphic user interface of a printing device when the excessive speed variation condition is present, the marking material quantity setting is at a marking material quantity maximum setting, and the tension of the transfer surface is at a tension maximum. The message provides instructions to use a different type media or initiate a service call.

Abstract: What is disclosed is a novel system and method for xerographic Dmax control based upon measurements made on the printed paper using an inline spectrophotometer (ILS) or similar device. The disclosed method is based upon directly measuring the color to actuator sensitivity. Each of the separations is controlled independently using an actuator specific to that color separation. The present method is effective at controlling the color of the solid primaries. The fact that the vector of change is highly correlated with solid color variation seen in the field suggests that the teachings hereof effectively increase the solid color stability. Increased solid color stability increases the color stability throughout the printer gamut and the stability of the gamut boundaries, which increases the robustness of gamut mapping algorithms. Advantageously, the present method can be combined with existing ILS-based maintenance architectures.

Abstract: What is disclosed is a novel system and method for xerographic Dmax control based upon measurements made on the printed paper using an inline spectrophotometer (ILS) or similar device. The disclosed method is based upon directly measuring the color to actuator sensitivity. Each of the separations is controlled independently using an actuator specific to that color separation. The present method is effective at controlling the color of the solid primaries. The fact that the vector of change is highly correlated with solid color variation seen in the field suggests that the teachings hereof effectively increase the solid color stability. Increased solid color stability increases the color stability throughout the printer gamut and the stability of the gamut boundaries, which increases the robustness of gamut mapping algorithms. Advantageously, the present method can be combined with existing ILS-based maintenance architectures.

Abstract: What is disclosed is a novel system and method for xerographic Dmax control based upon measurements made on the printed paper using an inline spectrophotometer (ILS) or similar device. The disclosed method is based upon directly measuring the color to actuator sensitivity. Each of the separations is controlled independently using an actuator specific to that color separation. The present method is effective at controlling the color of the solid primaries. The fact that the vector of change is highly correlated with solid color variation seen in the field suggests that the teachings hereof effectively increase the solid color stability. Increased solid color stability increases the color stability throughout the printer gamut and the stability of the gamut boundaries, which increases the robustness of gamut mapping algorithms. Advantageously, the present method can be combined with existing ILS-based maintenance architectures.

Abstract: What is disclosed is a system and method for efficiently and accurately estimating the complete TRC for a color marking device equipped with a multi-center cluster halftone screen which has a similar halftone tiling geometry and a similar growth specified by a corresponding single-center cluster halftone screen. The present method introduces a cluster-based printer model which establishes a relationship between a color output of a single-center cluster halftone screen and a color output of a multi-center cluster halftone screen. The present cluster-based printer model determines the complete TRC for the multi-center cluster halftone screen using the measurements for the single-center cluster halftone screen. Results of halftone dot linearization with different printing devices demonstrates that high accuracy can be achieved using the reduced measurements from the single-center cluster halftone screen.

Abstract: A method for monitoring an image printing system that prints color images on an image bearing surface movable in a process direction is provided. The method includes placing marking material to form a row comprising a plurality of registration marks on the image bearing surface, wherein each row of registration marks extends along a cross-process direction transverse to the process direction; detecting a position of each registration mark using a linear array sensor extending in the cross-process direction, wherein the position of each registration mark is detected in both the process and cross-process direction; determining a process direction misregistration between the registration marks of each row in the process direction and cross-process direction misregistration between registration marks from each of the rows.

Abstract: What is disclosed is a novel system and method for xerographic Dmax control based upon measurements made on the printed paper using an inline spectrophotometer (ILS) or similar device. The disclosed method is based upon directly measuring the color to actuator sensitivity. Each of the separations is controlled independently using an actuator specific to that color separation. The present method is effective at controlling the color of the solid primaries. The fact that the vector of change is highly correlated with solid color variation seen in the field suggests that the teachings hereof effectively increase the solid color stability. Increased solid color stability increases the color stability throughout the printer gamut and the stability of the gamut boundaries, which increases the robustness of gamut mapping algorithms. Advantageously, the present method can be combined with existing ILS-based maintenance architectures.

Abstract: A marking device is controlled to mark a media sheet with halftone dots selected from a set of image halftone dot representations. The marking device is controlled to mark a monitored surface with halftone dots selected from a set of control halftone dot representations to form test patches of different nominal marking densities. Measured marking densities are acquired using a density sensor for the test patches marked on the monitored surface. The set of control halftone dot representations is updated based on the measured marking densities and the nominal marking densities.

Abstract: What is disclosed is a system and method for efficiently and accurately estimating the complete TRC for a color marking device equipped with a multi-center cluster halftone screen which has a similar halftone tiling geometry and a similar growth specified by a corresponding single-center cluster halftone screen. The present method introduces a cluster-based printer model which establishes a relationship between a color output of a single-center cluster halftone screen and a color output of a multi-center cluster halftone screen. The present cluster-based printer model determines the complete TRC for the multi-center cluster halftone screen using the measurements for the single-center cluster halftone screen. Results of halftone dot linearization with different printing devices demonstrates that high accuracy can be achieved using the reduced measurements from the single-center cluster halftone screen.

Abstract: A method for monitoring an image printing system that prints color images on an image bearing surface movable in a process direction is provided. The method includes placing marking material to form a row comprising a plurality of registration marks on the image bearing surface, wherein each row of registration marks extends along a cross-process direction transverse to the process direction; detecting a position of each registration mark using a linear array sensor extending in the cross-process direction, wherein the position of each registration mark is detected in both the process and cross-process direction; determining a process direction misregistration between the registration marks of each row in the process direction and cross-process direction misregistration between registration marks from each of the rows.

Abstract: A marking device is controlled to mark a media sheet with halftone dots selected from a set of image halftone dot representations. The marking device is controlled to mark a monitored surface with halftone dots selected from a set of control halftone dot representations to form test patches of different nominal marking densities. Measured marking densities are acquired using a density sensor for the test patches marked on the monitored surface. The set of control halftone dot representations is updated based on the measured marking densities and the nominal marking densities.

Abstract: A method and apparatus are provided to calibrate a xerographic print engine toner concentration sensor to accurately control the toner concentration to a specified operating target. At least two control patches are imaged onto a photoreceptor. Each patch has a different voltage level where the voltage levels are the difference between the exposure discharge voltage and the developmental roll voltage. The relative reflectivity of each patches is obtained. The latent patches are repeatedly developed at different toner concentrations. The reflectivities of the patches formed at the same toner concentration are combined to obtain a combined reflectivity for that toner concentration. As a result, a toner concentration curve is obtained that has an improved response relative to the toner concentration curves that correspond to each of the individual voltage levels.