Abstract: For printing, the principle of the continuous deflected jet is used: a device (1) discharges a continuous stream (2) of a conductive liquid, which is deflected by an electric field created by a deflecting electrode (8) and directed toward a gutter (6). The printing of drops (12) is performed by fragmenting the continuous jet (2) into a segment (10) formed opposite a shield electrode (14) upstream of the deflecting electrode (8), so that the segment (10) is not deflected and can be directed toward a substrate (16).

Abstract: Ink jet printing method, in which the jet (14) is broken up in small and large drops at a fixed point (B), and the drops (16a, 16b) are charged according to the length (l, L) of the break segment (18), in other words according to their diameter. This configuration overcomes transition problems. The charging means (22) can also selectively deflect drops (16b).

Abstract: For printing, the principle of the continuous deflected jet is used: a device discharges a continuous stream of a liquid, which is deflected by an electric field created by a plurality of deflecting electrodes and directed toward a gutter. The printing of drops is performed by fragmenting the continuous jet into a segment formed opposite a shield electrode upstream of the deflecting electrode, so that the segment is not deflected and can be directed toward a substrate. The deflection electrodes are separated by an insulator and a variable potential is applied to each electrode; the potential for the entire set of electrodes cancels out such that the jet is not charged.

Abstract: For printing, the principle of the continuous deflected jet is used: a device (1) discharges a continuous stream (2) of a conductive liquid, which is deflected by an electric field created by a deflecting electrode (8) and directed toward a gutter (6). The printing of drops (12) is performed by fragmenting the continuous jet (2) into a segment (10) formed opposite a shield electrode (14) upstream of the deflecting electrode (8), so that the segment (10) is not deflected and can be directed toward a substrate (16).

Abstract: The generator according to the invention operates by strong stimulation in the form of pulses (?) so as to generate drops, particularly for ink jet printing purposes. This choice enables breaking the jet (30) close to the ejection (16) and reduces the interference ratio. A generator with piezoelectric stimulation is particularly suitable.

Abstract: Ink jet printing method, in which the jet (14) is broken up in small and large drops at a fixed point (B), and the drops (16a, 16b) are charged according to the length (l, L) of the break segment (18), in other words according to their diameter. This configuration overcomes transition problems. The charging means (22) can also selectively deflect drops (16b).

Abstract: Nutritional or ingestible ink composition for ink jet printing which is liquid at ambient temperature comprising: a) a binder comprising at least 0.5% by weight, with respect to the total weight of the ink, of at least one zein; b) a solvent comprising at least 10% by weight, with respect to the total weight of the ink, of one or more nutritional or ingestible solvent(s); c) at least 0.1% by weight, with respect to the total weight of the ink, of one or more nutritional or ingestible dye(s) and/or pigment(s). Dispersion of particles of at least one pigment in at least one polar solvent comprising at least one zein as dispersing agent. Use of at least one zein to facilitate the dispersing of particles of at least one pigment in at least one polar solvent and to stabilize the said dispersion. Process for marking a substrate, in particular a foodstuff, by ink jet printing with the said composition and substrate, for example eggshell, provided with such a marking.

Abstract: To clean a print head of an ink jet printer comprising an ink gun (1), connected, by means of devices capable of being controlled, to an ink chamber (2), a solvent chamber (8), a vacuum source (16), and an ink collection gutter (22) capable of being connected in a controlled manner to a vacuum source (16), the following steps are performed: (1) an interruption of a hydraulic connection between the gun (1) and the ink chamber (2) is ordered, (2) the gun (1) is connected to the vacuum source (16), (3) the solvent chamber (8) is hydraulically connected to the vacuum source (16) via a circuit (12, 14, 20) comprising the ink gun (1).

Abstract: An ink jet printer is characterised in that a connection part (1) of an umbilical connected to a connection part of a print head of the printer, comprises: first (12, 13, 14, 15, 17, 18, 20–23, 25) and second means (12, 14, 15, 16, 25) for positioning the umbilical electrical terminations (13, 19) and hydraulic terminations (24) mechanically fixed to the connection part (1) of the umbilical; third (12, 28) positioning means mechanically connected to the umbilical, and fourth positioning means (31, 48) mechanically connected to the connection part (3) of the print head, the third (12, 28) positioning means and the fourth positioning means (31, 48) cooperating to position the connection part (1) of the umbilical with respect to the connection part (3) of the print head. A translation movement alone is necessary to connect the umbilical onto the print head.

Abstract: An ink composition for continuous deflected jet printing that is liquid at room temperature and that contains: a binder; one or more dyes and/or pigments; and a solvent; wherein the said solvent contains more than 70% by weight—relative to the total weight of the ink—of propylene carbonate, and less than 10% by weight, preferably less than 5%, more preferably less than 1% and best 0% by weight of water.

Abstract: An ink jet printer is characterised in that a connection part (1) of an umbilical connected to a connection part of a print head of the printer, comprises: first (12, 13, 14, 15, 17, 18, 20-23, 25) and second means (12, 14, 15, 16, 25) for positioning the umbilical electrical terminations (13, 19) and hydraulic terminations (24) mechanically fixed to the connection part (1) of the umbilical; third (12, 28) positioning means mechanically connected to the umbilical, and fourth positioning means (31, 48) mechanically connected to the connection part (3) of the print head, the third (12, 28) positioning means and the fourth positioning means (31, 48) cooperating to position the connection part (1) of the umbilical with respect to the connection part (3) of the print head. A translation movement alone is necessary to connect the umbilical onto the print head.

Abstract: An ink composition for continuous deflected jet printing that is liquid at room temperature and that contains: a binder; one or more dyes and/or pigments; and a solvent; wherein the said solvent contains more than 70% by weight—relative to the total weight of the ink—of propylene carbonate, and less than 10% by weight, preferably less than 5%, more preferably less than 1% and best 0% by weight of water.

Abstract: Ink composition, in particular for continuous deflected ink jet printing comprising: a binder one or several dyes and/or pigments, and a solvent in which the said solvent comprises at least 10% by weight—in relation to the total weight of the ink—of 1,3-dioxolane, at least 5% by weight of one or several other organic compounds that can dissociate the ionisable species in the ink, and less than 5% water.

Abstract: Process and device for cleaning the nozzles of ink jet printers, and the print head incorporating such a device. A fixed cleaning jet (22) is installed on the print head, downstream of the ink nozzle to be cleaned (18) and offset to one side of it. When the ink jet stops, a given volume of solvent is sprayed by this cleaning jet, which hits the nozzle (18) at an angle. In this way the front face of the droplet generator is cleaned and scoured, and the ink residues are ejected towards the opposite side of the housing (36). Dry compressed air is then blown through the cleaning jet towards the ink nozzle (18) to dry the front of the nozzle and the ink residues deposited on the side of the housing (36).

Abstract: A spraying control system for an electrically conducting liquid (3) emitted in the form of a pressurized jet (4) through at least one nozzle (2). The system contains apparatus for separating the liquid into drops, apparatus for electrically charging the drops and apparatus for applying an electrical deflection field to the charged drops. The system includes a first (8) and a second (6) monolithic element each with a continuous surface, laid out such that the continuous surfaces are facing each other and define a space (5) between them in which the pressurized jet (4) is emitted through the nozzle (2). The elements (6,8) include apparatus for continuously setting up potentials on the continuous surfaces to obtain the electrical charge of the drops and the electrical deflection field. The system also includes electronic control (31 to 36) for the potentials and apparatus for checking the intensity of electrical currents that can circulate on the continuous surfaces.

Abstract: Process for modification of the position at which electrically-charged ink droplets arrive on a substrate (27), the droplets being charged by charge electrodes (20) connected to a voltage generator, the paths of the droplets being affected by the action of deviation electrodes (23, 24) that deviate the droplets depending on the value of their electrical charge, between N positions defining a frame obtained by a burst of droplets in the form of a straight segment approximately parallel to an X direction along which the substrate advances, process characterized in that an additional random voltage equal to a fraction less than 1 of the difference between the nominal voltages to be applied to the charge electrodes for each droplet and for one of the two immediately adjacent droplets in the frame, is applied in addition to a nominal voltage to be applied to each droplet charging means.

Abstract: Process for compensation of mechanical defects in an ink jet printer in which the ink viscosity, the jet velocity, the distance at which the ink jet is broken into droplets and the phase are independently servocontrolled to respect set values, process according to which the droplet arrival position is compared with a reference position, and mechanical defects are compensated by varying the electrical charge on the droplets. The invention also relates to a printer equipped with checking and servocontrol means so that compensation according to the process can be applied. The mechanical assembly of the printer will thus be simplified.

Abstract: This invention relates to an ink jet printer and a method of managing the ink quality of such a printer, wherein information on ink pressure P, temperature T, jet speed V, and the nominal ink characteristics (&rgr;n(T), &mgr;n(T)) is available. When the machine is started for the first time, the ink jet is varied at its nominal value and the resulting pressure is measured so as to determine the values a and b characteristic of the ink circuit, the characteristics of the utilized ink &rgr;(T), &mgr;(T), and the difference in level between the print head and the pressure transducer H. These values allow to set the desired pressure value and to take corrective action on ink quality.

Abstract: Process for compensation of a defect in the advance of a print substrate by modifying the arrival position of ink droplets with a variable electrical charge on the substrate (27), these droplets being charged in a variable and sequential manner, the paths of the droplets being affected by deviation electrodes (23, 24) deviating the droplets to one of N positions defined by their row j (1≦j≦N), the N positions defining a frame obtained by a burst of droplets in the form of a straight line segment parallel to an X direction along which the substrate advances.

Abstract: The present invention relates to an ink circuit comprising an ink cartridge (10), an additive cartridge (11), a recovery tank (12), a storage tank or accumulator 913), a main filter (24), solenoid valves (8), an ink transfer pump (14) equipped with a pressure/temperature sensor (53), an air pressure regulator (30), said ink circuit comprising a double face support unit with a hydropneumatic face and an electronic face making it possible to separate the hydraulic, pneumatic and electronic assemblies, all the functional components being fitted outside on one or other of the two faces.