Abstract: An ink composition is provided which is suitable for use in an ink jet printer and comprises solvent, colourant and binder, wherein the solvent comprises methyl acetate. The composition is particularly suitable for printing on polymeric substrates, eg polypropylenes and polyethylenes.

Abstract: An ink composition is provided which is suitable for use in an ink jet printer and comprises solvent, colourant and binder, wherein the solvent comprises methyl acetate. The composition is particularly suitable for printing on polymeric substrates, eg polypropylenes and polyethylenes.

Abstract: A common problem in vertical inkjet printers is that an air bubble is formed within the filter and so preventing correct operation of the printhead. Accordingly, a filter for use in an inkjet printer has a housing having an inlet and an outlet, with a filter element which is tapered towards the outlet for, in use, removing unwanted substances from ink flowing through the housing. A bleed tube has an inlet on the inlet side at the tapered end of the filter element, for removing trapped air from the inlet side of the filter element.

Abstract: A method is disclosed for controlling a multi-nozzle CIJ printhead having a pressure modulator for causing streams of ink emitted from the nozzles to be broken up into individual droplets, and charge electrodes 6 and charge electrode controllers for controllably applying a charge to individual ones of the droplets in each stream. The method involves generating a modulation waveform to operate the pressure modulator to cause droplets to be generated in each stream and operating the charge controllers to supply a charge signal waveform to each charge electrode. The charges applied to the streams of droplets are compared to a reference or threshold value. The number of droplet streams in which the droplet charges exceed the reference or threshold value is determined plural times and an average value for the number is calculated. This step is repeated a number of times and if the average is less than the average previously calculated then the threshold or reference value is reduced.

Abstract: E1 A CIJ printhead includes a droplet deflector electrode having one or more windows formed therein, and a phase or velocity detector electrode disposed within the window. A method of forming the electrodes by plating multiple conductive and dielectric layers is also disclosed.

Abstract: A method for adjusting the amplitude of the pressure modulation waveform in a multi-nozzle continuous jet printhead having a pressure modulator for causing streams of ink emitted from the nozzles to be broken up into individual droplets, and charge electrodes and change electrode controllers for controllably applying a charge to individual ones of the droplets in each stream.

Abstract: A continuous ink-jet printing method in which a stream of droplets issue from a nozzle of a continuous ink-jet printhead and a print substrate is moved past the printhead. The deflection electrodes of the printhead being disposed at a preselected angle relative to the path of movement of said print substrate. In accordance with said deflection electrode angle, for each of a series of droplets to be printed on said substrate to form an image, the value of the charge to be applied to the droplet is determined. The speed of movement of the print substrate relative to the printhead is determined and the values of the charges to be applied to the droplets in said stream corrected and the number of uncharged droplets between printable droplets adjusted in accordance with the determined speed of the substrate before the respective charges are applied to each of the droplets for printing.

Abstract: A droplet generator for a multi-jet CIJ printhead that has an ink chamber with plural orifices for the emission of fluid streams. An actuator drive armature is disposed within the ink chamber and, at one side, has a one-piece solid drive wall with a pair of major faces which are tapered towards one another in the direction away from the other side. At the other side there is only a single pair of transducer mountings disposed adjacent the ends of the drive wall.

Abstract: A CIJ printer has a drop generator and a mount. The mounting of the drop generator on the mount is by a pair of fixing screws locating in countersunk screw-threaded bores in the drop generator and disposed in the resilient bushings located in corresponding bores in the mount. To reduce the transfer of ultrasonic vibrations and mounting stresses imposed on the drop generator, two pairs of point contacts protrude between the mount and the drop generator. Each pair being in alignment with the centre of a respective one of the fixing screws and on respective lines perpendicular to a line connecting the centers of the fixing screws.

Abstract: We provide a method of printing using a multi-nozzle ink jet print head having a pressure modulator for causing streams of ink emitted from the nozzles to be broken up into individual droplets. The nozzles are divided into a plurality of groups of nozzles, and groups of charge electrodes correspond, each group of charge electrodes having a respective charge controller. In the method a modulation waveform is generated to operate the pressure modulator to cause droplets to be generated in each stream. Independently for each group of charge electrodes, the respective charge controller is operated to supply a charge signal waveform to each charge electrode in turn, the phase of the charge signal waveform relative to the modulation waveform is adjusted between 0 and 360 degrees in a number of steps, and the optimum phase relationship to achieve proper charging for each droplet stream is determined in turn.

Abstract: A liquid collection apparatus comprises a liquid collecting device and liquid conduit for transferring liquid from the liquid collection device. Porous liquid absorption device is positioned between the liquid collection device and the liquid conduit. Pump device pumps liquid from the liquid conduit, the pump device generating a pressure in the conduit that is sufficient to draw liquid through the liquid collection device but is insufficient to draw a gas/liquid surface through the liquid absorption device.

Abstract: A container (1) is proposed for replenishing ink or solvent in an ink jet printer ink system. The container (1) has a plug-in connector (7) for attachment to a mating connector on the ink system along an axis so that fluid within the container (1) can be transferred to the ink system. Adjacent to the connector (7) a cam surface is disposed so as to cause the connector (7) to disconnect from the mating connector on rotation of the container (1) in a direction about the axis.

Abstract: A method of and apparatus for flushing a printhead of a continuous ink jet printer is disclosed, in which the printer has a feed line to which ink is normally fed in use. A gutter line is also provided through which unused ink is removed from the printhead. A bleed line is connected to the printhead for bleeding ink from the printhead, and a flushing line is connected to the printhead through which line flushing fluid is selectively caused to flow through the flushing line to the printhead and from the printhead through the bleed line.

Abstract: An ink jet ink is disclosed which comprises a binder, a colorant, a conductivity controller and a liquid vehicle in which at least the binder and colourant are soluble, the binder being a nitrocellulose having a viscosity of 15 centipoise or less as measured by method 1 herein; or a weight average molecular weight of not more than 25,000 as measured by method 3 herein; or the nitrocellulose has both the said viscosity and the said weight average molecular weight;and in that the nitrocellulose has a nitrogen content of at least 9.5% by weight as measured by the method of ASTM D 301-72;and in that the ink has a viscosity of 1.6 to 4 centipoise at 25.degree. C. using a Brookfield DV-11+ viscometer with a number 00 spindle at 60 r.p.m (method 2 herein).

Abstract: A method of making an electrode assembly for a continuous ink jet printer. The method includes disposing a plurality of conductive tracks side by side on a flexible non-conductive film, each of said conductive tracks having an electrode portion, a conductor portion and a connector portion. The film is mounted on a support block with the electrode portion of each conductive track disposed at an end surface of the block.

Abstract: A method of printing with a multi-nozzle continuous ink jet printer 1 that has a row of nozzles through which respective streams of ink 3 are emitted before being broken up into columns of droplets, a charge electrode assembly has a plurality of charge electrodes for charging individual droplets in each of the columns of droplets, deflection electrodes 5, 6 for deflecting charged droplets according to the charge thereon and an auxiliary charge electrode 8. A compensating charge is applied to all droplets in a chosen row by the auxiliary charge electrode causing differential deflection that allows drops from adjacent rows of droplets printed in alignment rather than offset from one another.

Abstract: A print head for a continuous ink jet printer has a nozzle through which ink is emitted and broken up into droplets under the action of a piezoelectric oscillator. A charge electrode applies charge to selected droplets and a deflection electrode deflects the path of the charged droplets to cause printing on a substrate. A gutter collects droplets which are not required for printing. A charge electrode, together with one of the deflection electrodes is movable in a direction transverse to the path of the droplets selectively under the action of pressurized ink fed from an ink supply. Similarly, the gutter is movable in the same way by another actuator.

Abstract: An armature (1) for an actuator drive for a multi-jet continuous ink jet printhead has, at one side, a row of transducer mountings (10). The armature (1) has a plurality of elongate slots (5) therethrough in a row parallel to the one side, each slot (5) extending away from the one side and being aligned intermediate to the transducer mountings (10), whereby lands (6) between the slots (5) are aligned with the transducer mountings (10).