The present disclosure provides an inkjet head device for inkjet printers, which includes a tubular base, a composite plate and an inkjet head assembly mounted on the composite plate; the composite plate includes a fiberglass plate and a plastic plate integrally connected to the fiberglass plate, the fiberglass plate is engaged with the open side of the base along an axial direction of the base, the plastic plate is located on a surface facing the base of the fiberglass plate. According to the inkjet head device for inkjet printers of the disclosure, the base plate is a composite plate formed by integrally connecting the fiberglass plate and the plastic plate, where the inkjet head assembly is mounted to form an integrated module, thus the disassembly, the assembly, or the maintenance are convenient.

Substrates can be inkjet printed using an aqueous inkjet ink composition having a dynamic viscosity of 5 centipoise (5 mPa-sec) or less at 25 C., and consisting essentially of: (a) a polymer-dispersed pigment colorant at 0.9-6 weight %; (b) a composition consisting of one or more compounds represented by the following Structure (I):
HOCH.sub.2CH.sub.2R(I)
wherein R is a substituted or unsubstituted phenyl group or a substituted or unsubstituted phenoxy group, at 0.5-2 weight %; and (c) a water-soluble humectant, co-solvents, or both, at 20 weight %. Each polymer-dispersed pigment colorant has a 50.sup.th percentile particle diameter of less than 70 nm and a 95.sup.th percentile particle diameter of less than 150 nm, measured using a dynamic light scattering particle size analyzer. Replenishment or maintenance fluids containing a Structure (I) compound can also be used during the inkjet printing process.

Substrates can be inkjet printed using an aqueous inkjet ink composition having a dynamic viscosity of 5 centipoise (5 mPa-sec) or less at 25 C., and consisting essentially of: (a) a polymer-dispersed pigment colorant at 0.9-6 weight %; (b) a composition consisting of one or more compounds represented by the following Structure (I):
HOCH.sub.2CH.sub.2R(I)
wherein R is a substituted or unsubstituted phenyl group or a substituted or unsubstituted phenoxy group, at 0.5-2 weight %; and (c) a water-soluble humectant, co-solvents, or both, at 20 weight %. Each polymer-dispersed pigment colorant has a 50.sup.th percentile particle diameter of less than 70 nm and a 95.sup.th percentile particle diameter of less than 150 nm, measured using a dynamic light scattering particle size analyzer. Replenishment or maintenance fluids containing a Structure (I) compound can also be used during the inkjet printing process.

A device for recovery of an atmosphere containing solvent vapours from at least one ink recovery reservoir of a print machine comprising: n (n1) filter(s) arranged downstream from the at least one ink recovery reservoir, each filter: comprising an inlet face, an outlet face and a filter body between these two faces, and each of the filter being upstream from a condenser or other solvent extraction structure, an atmosphere output from the at least one ink recovery reservoir passing through a separator and through the inlet face, and then through the filter body and through the outlet face before being sent to the solvent extraction structure, the device further comprising at least one second reservoir to recover liquid from the separator.

A device for recovery of an atmosphere containing solvent vapours from at least one ink recovery reservoir of a print machine comprising: n (n1) filter(s) arranged downstream from the at least one ink recovery reservoir, each filter: comprising an inlet face, an outlet face and a filter body between these two faces, and each of the filter being upstream from a condenser or other solvent extraction structure, an atmosphere output from the at least one ink recovery reservoir passing through a separator and through the inlet face, and then through the filter body and through the outlet face before being sent to the solvent extraction structure, the device further comprising at least one second reservoir to recover liquid from the separator.

An ink-jet recording apparatus configured to record an image based on image data on a sheet, the ink-jet recording apparatus includes a first roller pair, a second roller pair, a carriage, a recording head, and a controller configured to: control the first roller pair and the second roller pair to perform intermittent conveyance of the sheet; control the carriage and the recording head to record a one-pass image on the sheet; and calculate an overlap amount, in the conveyance direction, of a one-pass image to be recorded on the sheet in a predefined one pass and a one-pass image to be recorded on the sheet in a next one pass after the predefined one pass.

An ink-jet recording apparatus configured to record an image based on image data on a sheet, the ink-jet recording apparatus includes a first roller pair, a second roller pair, a carriage, a recording head, and a controller configured to: control the first roller pair and the second roller pair to perform intermittent conveyance of the sheet; control the carriage and the recording head to record a one-pass image on the sheet; and calculate an overlap amount, in the conveyance direction, of a one-pass image to be recorded on the sheet in a predefined one pass and a one-pass image to be recorded on the sheet in a next one pass after the predefined one pass.

An electrostatic deflection inkjet printer has a main printer body separated by a vapor barrier into an electrical region and a fluid region. Electrically operated valves are provided in the fluid region. Control circuitry for deciding when to operate the valves is provided in the electrical region. Valve drive circuitry, for generating drive currents for the valves, is provided in the fluid region and is in data communication with the control circuitry via wiring, which may be a serial bus, that passes through the vapor barrier. This reduces the number of electrical connections that need to pass through the vapor barrier. A circuit carrier for the valve drive circuitry may be mounted on a valve block for the valves, and an electrically insulating material may cover the circuit carrier. The electrically insulating material may extend partially or wholly around the valve block.

The disclosure relates to a method for avoiding contamination of a printing plate given surface-covering coating of a dust-forming recording medium (e.g. an uncoated paper) with a coating substance (e.g. a primer) in an inkjet printing operation. The method can include feeding the recording medium at a feed velocity that is greater than 20 meters per minute; continuously printing of the coating substance onto the recording medium by at least one print head including a plurality of print nozzles, the coating substance being printed at a constant, predetermined applied quantity per area. A nip between the print head and the recording medium is provided such that a fluid-dynamic eddy is created between the recording medium and the print head and/or the printing plate. The disclosure also related to a printing system that is configured to implement the method.

A continuous inkjet printer has an ink circuit comprising an ink tank, an ink pump and a Venture suction device. The Venturi is used to suck an extra solvent or ink as required. However, if the ink tank is empty, no ink can be pumped through the Venture and so it will not develop suction and thus, cannot be used to suck in an initial supply of ink to an empty tank. A removable ink container may be connected to the ink tank or elsewhere in the ink circuit, for example, between the Venturi outlet and the pump inlet. Compressing the ink container manually will force ink into the ink circuit. When enough ink has been added, the pump will drive ink through the Venturi and suction will be generated.