DE69837297T2 - Inkjet nozzle with electromagnetically activated ink piston - Google Patents

Description

Field of the invention

The The present invention relates to the field of ink jet printing systems.

State of the art

It Many different types of printing have been invented, from which is a big one Number present are in use. The known forms of printing have a variety from procedures to the print carrier with relevant Label labeling media. Frequently used forms of the Printing includes offset printing, laser printing and copiers, dot matrix impact printers, Thermal paper printers, film recorders, thermal wax printers, dye sublimation printers and inkjet printers, both in the drop-type design on demand (drop on demand) as well as with continuous stream. Looking at costs, speed, quality, reliability, Simplicity of construction and functioning etc., then each one has Kind of printers have their own advantages and problems.

In In recent years, the field of inkjet printing has been taking each individual ink pixel comes from one or more ink nozzles, primarily because of its cost-effective and versatile nature always wider distribution found.

It Many different techniques of inkjet printing were invented. For an overview in the art, reference is made to an article by J. Moore, "Non-Impact Printing: Introduction and Historical Perspective ", Output Hard Copy Devices, ed R. Dubeck and S. Sherr, pp. 207-220 (1988).

inkjet themselves are available in many different designs. The use of a continuous Ink flow in inkjet printing seems at least on the To go back to 1929 in U.S. Patent No. 1,941,001 to Hansell, a simple Form of electrostatic inkjet printing with continuous Electricity is disclosed.

The Sweet's U.S. Patent 3,596,725 also discloses a process of continuous ink-jet printing, including the step in which the ink jet stream through a high-frequency electrostatic Field is modulated so as to cause the droplet separation. This technique is used by some manufacturers including Elmjet and Scitex (see also U.S. Patent No. 3,373,437 to Sweet et al.). still used.

Piezoelectric ink jet printers are also a form of commonly used ink jet printing devices. Piezoelectric systems are disclosed by Kyser et al. in U.S. Patent No. 3,946,398 (1970), which employs membrane-assisted operation, by Zolten in U.S. Patent 3,683,212 (1970), which discloses an operation based on extrusion through a piezoelectric crystal Stemme, in U.S. Patent No. 3,747,120 (1972), discloses a bending-based piezoelectric process. Howkins in U.S. Patent No. 4,459,601 discloses piezoelectric ejection activation of the ink-jet stream, and Fischbeck discloses in US Pat US 4,584,590 a shear type of piezoelectric traveling element.

The Document JP-A-4126255 discloses an ink jet print head a plurality of nozzle arrangements, wherein each of these arrangements comprises a piston, and an electrical Coil which is disposed adjacent to the piston and electrically a nozzle activation signal is connected, wherein upon activation of the activation signal the piston from the spool is caused to move from an ink charging position to an ink ejecting position to move, causing the ejection caused by ink from the ink ejection port becomes.

Recently, thermal ink jet printing has become an extremely widespread form of ink jet printing. The ink-jet printing techniques include those of Endo et al. in GB 2 007 162 (1979) and Vaught et al. in U.S. Patent 4,490,728. Both ink-jet printing techniques disclosed in these references above rely on the activation of an electrothermal actuator, which results in the creation of a bubble in a confined space such as a nozzle, which in turn causes ejection of ink onto a pertinent print medium from a passage associated with connected to the bounded space. Printing devices using an electrothermal actuator are used by Produced by manufacturers such as Canon and Hewlett Packard.

As From the above, many different types of Printing technologies available. Ideally should have a printing technology over a whole host of desirable ones Features. These include a low cost Construction and inexpensive operation, high-speed operation, a safe and continuous long-term operation, etc. Every technology like their very own advantages and disadvantages in the fields of Cost, speed, quality, Reliability, power consumption, simplicity of design and operation, durability and consumables.

It Many inkjet printing devices are known. regrettably is the production of technical processes in mass production of inkjet heads pretty hard. For example, often the mouth or nozzle plate built separately from the ink supply and ink ejection mechanism, and associated with this mechanism at a later stage (Hewlett-Packard Journal, Vol. 36, No. 5, pp. 33-37 (1985)). These separate Material handling steps involved in handling such precision devices are required, often result in the production of a considerable Increase in expenditure.

Furthermore Often, side-shoot inkjet technologies (US patent No. 4,899,181), but here too capital investment in given amount the extent of through Mass production achievable throughput is limited.

Furthermore often more sophisticated techniques are used. These can be the Electroplating of Nickel Phases (Hewlett-Packard Journal, Vol. 36, No. 5, p 33 to 37 (1985)), electroerosion, laser ablation (US Pat No. 5,208,604) comprising micro-punches, etc.

Of the Use of the above techniques is likely to be a significant overhead in the mass production of inkjet printheads and beats therefore strongly reflected in their final costs.

From therefore would be it desirable if an efficient system for mass production of inkjet printheads could be developed.

Summary of the invention

It An object of the present invention is an ink jet printing mechanism with a series of ink ejection nozzles, wherein the nozzles an internal, selective actuator mechanism, in which the nozzles individually activated by creating a field around these nozzles become. The invention accordingly looks for a printhead Claim 1 before. Advantageous embodiments are specified in the dependent claims.

Short description of drawings

regardless any other forms which are also within the scope of the present Invention can fall Now, preferred forms of the invention are merely exemplary with reference to the accompanying drawings.

1 Fig. 10 is an exploded perspective view illustrating the structure of a single ink jet nozzle according to an embodiment of the present invention;

2 Fig. 10 is a timing diagram illustrating the operation of an embodiment;

3 Fig. 12 is a cross-sectional top view of a single ink nozzle constructed in accordance with an embodiment of the present invention;

4 represents a legend of in 5 to 21 specified materials available;

5 to 21 FIG. 12 illustrates sectional views of the manufacturing steps in a form of construction of an ink-jet printhead nozzle. FIG.

Description of IJ01 F

In 1 is an exploded perspective view showing the structure of a single ink jet nozzle 4 according to the principles of the present invention.

The nozzle 4 works on the principle of electromechanical energy conversion and includes a magnetic coil 11 at a first end 12 electrically to a magnetic disk 13 is connected, which in turn with a power source (eg 14 ) connected to the activation of the ink nozzle 4 is used. The magnetic disk 13 can be constructed of electrically conductive iron.

Further, a second, magnetic piston 15 provided, which is also constructed again of soft magnetic iron. Will the solenoid coil 11 energized, the piston becomes 15 to the stationary magnetic disk 13 pulled out. The piston thereby presses on the ink in the nozzle 4 , being in the nozzle chamber 17 a region of high pressure is generated. This leads to a movement of the ink in the nozzle chamber 17 , and in a first design, for subsequent ejection of an ink drop. There are a number of passages (eg 20 ) provided so that ink in the area of the magnetic coil 11 from the passages 20 at the top of the piston 15 when it is pressed out to the lower plate 13 moved. This prevents in the area of the magnetic coil 11 ink trapped the pressure on the piston 15 increases and thereby increases the magnetic forces that cause the movement of the piston 15 are necessary.

In 2 is at 30 a timing diagram of the piston flow control signal is shown. Initially, the solenoid current is activated 31 to move the piston and cause ejection of a drop from the ink nozzle. After about two microseconds, the current to the solenoid is interrupted. At the same time or at a later time 32 a countercurrent of about half the forward current is applied. Since the piston has a residual magnetism, is due to the countercurrent 32 the piston is caused to move back to its original position. A set of torsion springs 22 . 23 ( 1 ) also supports the return of the piston to its original position. The countercurrent is interrupted before the magnetism of the piston 15 reversed, which would otherwise cause the piston to be retracted to the fixed plate. Regarding 1 leads the forced return of the piston 15 in its rest position to a low pressure in the chamber 17 , This may cause ink from the outlet nozzle 24 begins to flow inward and also air into the chamber 17 is admitted. The forward speed of the drop and the reverse speed of the ink into the chamber 17 are caused by the tearing off of the ink drop in the area around the nozzle 24 certainly. Under its own pulse, the ink droplet then continues the path toward the recording medium. Because of the surface tension of the ink at the nozzle tip 24 the nozzle fills up again. Shortly after the time of drop break, a meniscus forms on the nozzle tip with an approximately concave hemispherical surface. The surface tension exerts a forward net force on the ink, resulting in refilling of the nozzle. The repetition rate of the nozzle 4 is therefore principally determined by the nozzle refilling time, which is in the range of 100 microseconds, depending on the device geometry, the surface tension of the ink, and the volume of the ejected drop.

Now, with respect to 3 an important aspect of the operation of the electromagnetically driven pressure nozzle described. When the solenoid 11 A current flows through the plate 15 strong to the plate 13 pulled out. The plate 15 experiences a downward force and begins to move to the plate 13 to move. This movement gives the ink within the nozzle chamber 17 a force impulse with. The ink is then ejected as described above. Unfortunately, the movement causes the plate 15 a pressure build-up in the area 64 between the plate 15 and the magnetic coil 11 , This pressure buildup would normally result in a decreased effectiveness of the plate 15 when ejecting ink.

In a first design, the plate comprises 15 however, preferably a series of passages (eg 20 ), which returns a flow of ink from the area 64 into the ink chamber, thereby reducing the pressure in the area 64 allow. This leads to an increased efficiency when using the plate 15 ,

The passages 20 preferably have a teardrop shape, wherein the diameter increases with increasing radial distance of the piston. The passage profile thereby provides minimal disturbance of the magnetic flux through the piston while at the same time increasing the structural strength of the piston 15 is maintained.

After the piston 15 has reached its end position, the current through the solenoid coil 11 reversed in his direction, causing a repulsion of the two plates 13 . 15 leads. In addition, the Tor sion spring acts (eg 23 ) so that the plate 15 is returned to its original position.

The use of a torsion spring (eg 23 ), has a number of substantial advantages, including a compact design and the construction of the torsion spring of the same material and in the same process steps as in the plate 15 ,

In an alternative design, the top of the plate contains 15 no succession of passages. Rather, the inner radial surface includes 25 the plate 15 Slots of substantially constant cross-sectional profile, in fluid communication between the nozzle chamber 17 and the area 64 between the plate 15 and the magnetic coil 11 stand. When the solenoid is activated 11 becomes the plate 15 to the anchor plate 13 pulled out and experiences a force leading to the plate 13 is directed. As a result of the movement, the fluid becomes in the range 64 compresses and experiences a higher pressure than its immediate environment. As a result, there is a flow of fluid from the slots in the inner radial surface 25 the plate 15 in the nozzle chamber 17 instead of. The flow of fluid into the chamber 17 causes in addition to the movement of the plate 15 ejecting ink from the ink jet orifice 24 , Again, by the movement of the plate 15 the torsion springs, eg 23 , elastically deformed. After completing the movement of the plate 15 becomes the magnetic coil 11 deactivated and a small countercurrent applied. The countercurrent acts so that it is the plate 15 from the anchor plate 13 repels. The torsion springs, eg 23 , act as an additional aid to the recovery of the plate 15 in their original or resting position.

manufacturing

Under return on 1 The nozzle device is constructed of the following main parts, including a nozzle tip 40 that has a passage 24 and may be constructed of silicon doped with boron. The radius of the passage 24 the nozzle tip is an important determinant of drop velocity and drop size.

Next is a CMOS silicon layer 42 provided on the the entire data storage and control circuit 41 is made for the operation of the nozzle 4 necessary is. In this layer is also a nozzle chamber 17 built up. The nozzle chamber 17 should be wide enough so that frictional resistance from the chamber walls does not significantly increase the force required for the piston. It should also be deep enough so that any air, when the piston returns to its idle state, makes its way through the nozzle opening 24 has not reached the piston device. When this happens, the introduced bladder can form a cylindrical surface rather than a hemispherical surface, which results in the nozzle not being properly replenished. It is also a dielectric and insulating CMOS layer 44 provided, which contains different current path parts for the power connection to the piston device.

Next is a fixed, two parts 13 . 46 comprehensive plate of ferroelectric material provided. The two parts 13 . 46 are electrically isolated from each other.

Next is a magnetic coil 11 intended. This may include a spiral coil of deposited copper. Preferably, a single spiral layer is used to avoid manufacturing difficulties, and copper is used because of low resistivity and high resistance to electromigration.

Next is a piston 15 made of ferroelectric material to maximize the generated magnetic force. The piston 15 and the stationary magnetic disk 13 . 46 surround the magnetic coil 11 as a torus. So only a small part of the magnetic flux is lost and it concentrates around the gap between the piston 15 and the fixed plate 13 . 46 ,

The gap between the fixed plate 13 . 46 and the piston 15 is one of the most important "components" of the pressure nozzle 4 , The size of the gap has a strong effect on the generated magnetic force and also limits the stroke of the piston 15 , A small gap is desirable in order to achieve a high magnetic force, and a large gap is desirable to the piston 15 allow a longer stroke, and then a smaller piston radius can then be used.

Next are the springs (eg 22 . 23 ) to return the piston 15 provided in its resting position after a drop was ejected. The springs (eg 22 . 23 ) can from the same Ma te rial and also be produced in the same processing steps, as it is the piston 15 the case is. In their interaction with the piston 15 act the springs (eg 22 . 23 ) preferably as torsion springs.

Finally, all surfaces are coated with passivation layers, which may be silicon nitride (Si ₃ N ₄ ), diamond-like carbon (DLC), or any other chemical inert, highly impermeable layer. The passivation layers are particularly important as far as the life of the device is concerned since the active device will be immersed in ink.

• 1. Verwendung eines doppelseitigen, polierten Wafers, Abscheiden von 3 μm epitaxialem Silizium, das stark mit Bor dotiert ist.
• 2. Abscheiden von 10 μm epitaxialem Silizium, je nach dem verwendeten CMOS-Prozess entweder von der p-Art oder n-Art.
• 3. Vervollständigung eines 0,5 μm-CMOS-Prozesses mit einer Poly- und zwei Metallschichten. Dieser Schritt ist in 5 gezeigt. Der Klarheit halber sei angemerkt, dass diese Abbildungen nicht ganz maßstabsgetreu sind und auch den Querschnitt durch irgendeine Einzelebene der Düse nicht exakt wiedergeben. 4 ist ein Schlüssel zu Darstellungen von verschiedenen Materialien bei diesen Herstellungsschaubildern, und auch auf solche von anderen Tintenstrahlkonfigurationen, auf die durch Querverweis hingewiesen ist.
• 4. Herunterätzen der CMOS-Oxidschichten bis auf das Silizium oder Aluminium unter Verwendung einer Maske 1. Diese Maske definiert die Düsenkammer, die Ränder der Druckkopfchips, und die Kontaktlöcher für die Kontakte von den Aluminiumelektroden zu den beiden Hälften der geteilten, feststehenden Magnetplatte.
• 5. Plasmaätzung des Siliziums bis auf die mit Bor dotierte, vergrabene Schicht, mittels des Oxids von Schritt 4 als Maske. Durch diese Ätzung wird das Aluminium im Wesentlichen nicht angeätzt. Dieser Schritt ist in 6 gezeigt.
• 6. Abscheiden einer Keimschicht aus einer Kobalt-Nickel-Eisen-Legierung. CoNiFe wird wegen einer hohen Sättigungsflussdichte von zwei Tesla und einer geringen Koerzivität gewählt. [Osaka, Tetsuya et al., A soft magnetic CoNiFe film with high saturation magnetic flux density, Nature 392, 796-798 (1998)].
• 7. Aufschleudern einer 4 μm dicken Resistschicht, Abdecken mit einer Maske 2 und Entwickeln. Diese Maske legt die geteilte, feststehende Magnetplatte fest, für die der Resist als Galvanisierungsform dient. Dieser Schritt ist in 7 gezeigt.
• 8. Elektroplattierung von 3 μm CoNiFe. Dieser Schritt ist in 8 gezeigt.
• 9. Abziehen des Resists und Ätzen der freigelegten Keimschicht. Dieser Schritt ist in 9 gezeigt.
• 10. Abscheiden von 0,1 μm Siliziumnitrid (Si₃N₄).
• 11. Ätzen der Nitridschicht unter Verwendung einer Maske 3. Diese Maske bildet die Kontaktlöcher von jedem Ende der Magnetspule zu den beiden Hälften der geteilten, feststehenden Magnetplatte.
• 12. Abscheiden einer Keimschicht aus Kupfer. Kupfer wird wegen seines geringen spezifischen Widerstands (was zu einem höheren Wirkungsgrad führt) und seinem hohen Elektromigrationswiderstand verwendet, was die Zuverlässigkeit bei hohen Stromdichten steigert.
• 13. Aufschleudern von 5 μm Resist, Abdecken mit Maske 4, und Entwickeln. Diese Maske definiert die spiralförmige Magnetspule und die Federstützen, für die der Resist als Galvanisierungsform wirkt. Dieser Schritt ist in 10 gezeigt.
• 14. Elektroplattierung von 4 μm Kupfer.
• 15. Abziehen des Resists und Ätzen der freigelegten Kupferkeimschicht. Dieser Schritt ist in 11 gezeigt.
• 16. Testung des Wafers. An diesem Punkt sind alle elektrischen Verbindungen fertiggestellt, Kontaktanschlussflecken sind zugänglich, und die Chips sind noch nicht voneinander getrennt.
• 17. Abscheiden von 0,1 μm Siliziumnitrid.
• 18. Abscheiden von 1 μm Opfermaterial. Diese Schicht bestimmt den Magnetspalt.
• 19. Ätzen des Opfermaterials mittels einer Maske 5. Diese Maske definiert die Federstützen. Dieser Schritt ist in 12 gezeigt.
• 20. Abscheiden einer Keimschicht aus CoNiFe.
• 21. Aufschleudern von 4,5 μm Resist, Abdecken mit Maske 6, und Entwickeln. Diese Maske definiert die Wände des Magnetkolbens plus die Federstützen. Der Resist bildet eine Galvanisierungsform für diese Teile. Dieser Schritt ist in 13 gezeigt.
• 22. Elektroplattierung von 4 μm CoNiFe. Dieser Schritt ist in 14 gezeigt.
• 23. Abscheiden einer Keimschicht aus CoNiFe.
• 24. Aufschleudern von 4 μm Resist, Abdecken mit einer Maske 7, und Entwickeln. Diese Maske definiert das Dach bzw. die Frontseite des Magnetkolbens, die Federn und die Federstützen. Der Resist bildet eine Galvanisierungsform für diese Teile. Dieser Schritt ist in 15 gezeigt.
• 25. Elektroplattierung von 3 μm CoNiFe. Dieser Schritt ist in 16 gezeigt.
• 26. Anbringen des Wafers auf einem Glasrohling und Rückätzen des Wafers mit KOH, wobei keine Maske beteiligt ist. Diese Ätzung dünnt den Wafer aus und stoppt an der vergrabenen, mit Bor dotierten Siliziumschicht. Dieser Schritt ist in 17 gezeigt.
• 27. Eine durch Plasmaätzung erfolgende Rückätzung der mit Bor dotierten Siliziumschicht auf eine Tiefe von (ungefähr) 1 μm unter Verwendung einer Maske 8. Diese Maske definiert den Düsenrand. Dieser Schritt ist in 18 gezeigt.
• 28. Eine Plasmarückätzung durch die mit Bor dotierte Schicht unter Verwendung einer Maske 9. Diese Maske definiert die Düse und den Rand der Chips. In diesem Stadium sind die Chips voneinander getrennt, aber immer noch auf dem Glasrohling angebracht. Dieser Schritt ist in 19 gezeigt.
• 29. Ablösen der Chips vom Glasrohling. Abziehen aller Klebe-, Resist-, Opfer- und freigelegten Keimschichten. Dieser Schritt ist in 20 gezeigt.
• 30. Einsetzen der Druckköpfe in ihre Umhausung, bei der es sich um ein Kunststoffformteil handeln kann, in das vorab Tintenkanäle eingebracht wurden, die verschiedene Tintenfarben an die entsprechenden Bereiche der Vorderfläche des Wafers liefern.
• 31. Anschließen der Druckköpfe an ihre untereinander verbundenen Systeme.
• 32. Die Vorderfläche der Druckköpfe hydrophobisieren bzw. wasserabweisend machen.
• 33. Auffüllen der fertiggestellten Druckköpfe mit Tinte und Testung derselben. Eine gefüllte Düse ist in 21 gezeigt.

One form of detailed manufacturing process that may be used to make monolithic inkjet printheads that operate in accordance with the principles taught by the present embodiment may be accomplished using the following steps:

• 1. Using a double-sided, polished wafer, depositing 3 μm of epitaxial silicon heavily doped with boron.
• 2. Deposit 10 μm of epitaxial silicon, depending on the CMOS process used, either of the p-type or n-type.
• 3. Completion of a 0.5 μm CMOS process with one poly and two metal layers. This step is in 5 shown. For the sake of clarity, it should be noted that these figures are not to scale and do not accurately represent the cross-section through any single plane of the nozzle. 4 is a key to representations of various materials in these manufacturing charts, as well as those of other ink jet configurations referred to by cross-reference.
• 4. Etch the CMOS oxide layers down to the silicon or aluminum using a mask 1. This mask defines the nozzle chamber, the edges of the printhead chips, and the contact holes for the contacts from the aluminum electrodes to the two halves of the split stationary magnetic disk.
• 5. plasma etch the silicon down to the boron-doped buried layer using the oxide of step 4 as a mask. By this etching, the aluminum is not etched substantially. This step is in 6 shown.
• 6. deposition of a seed layer of a cobalt-nickel-iron alloy. CoNiFe is chosen because of its high saturation flux density of two Tesla and low coercivity. [Osaka, Tetsuya et al., A soft magnetic CoNiFe film with high saturation magnetic flux density, Nature 392, 796-798 (1998)].
• 7. Spin on a 4 μm thick resist layer, cover with a mask 2 and develop. This mask defines the split, stationary magnetic plate for which the resist serves as a galvanizing mold. This step is in 7 shown.
• 8. Electroplating of 3 μm CoNiFe. This step is in 8th shown.
• 9. Peel off the resist and etch the exposed seed layer. This step is in 9 shown.
• 10. Deposit 0.1 μm silicon nitride (Si ₃ N ₄ ).
• 11. Etching the nitride layer using a mask 3. This mask forms the contact holes from each end of the magnetic coil to the two halves of the divided stationary magnetic disk.
• 12. deposition of a seed layer of copper. Copper is used because of its low resistivity (resulting in higher efficiency) and its high electromigration resistance, which increases reliability at high current densities.
• 13. Spin on 5 μm resist, cover with Mask 4, and develop. This mask defines the spiral magnetic coil and the spring supports for which the resist acts as a galvanizing mold. This step is in 10 shown.
• 14. Electroplating of 4 μm copper.
• 15. Peel off the resist and etch the exposed copper seed layer. This step is in 11 shown.
• 16. Testing the wafer. At this point, all electrical connections are completed, contact pads are accessible, and the chips are not yet separated.
• 17. Deposit 0.1 μm silicon nitride.
• 18. Deposition of 1 μm sacrificial material. This layer determines the magnetic gap.
• 19. Etch the sacrificial material using a mask 5. This mask defines the spring supports. This step is in 12 shown.
• 20. Separation of a seed layer of CoNiFe.
• 21. Spin 4.5 μm resist, cover with Mask 6, and develop. This mask defines the walls of the magnetic piston plus the spring supports. The resist forms a galvanizing mold for these parts. This step is in 13 shown.
• 22. Electroplating of 4 μm CoNiFe. This step is in 14 shown.
• 23. Separation of a seed layer of CoNiFe.
• 24. spin on 4 μm resist, cover with a mask 7, and develop. This mask defines the roof or the front of the magnetic piston, the springs and the spring supports. The resist forms a galvanizing mold for these parts. This step is in 15 shown.
• 25. Electroplating of 3 μm CoNiFe. This step is in 16 shown.
• 26. Attach the wafer to a glass blank and back etch the wafer with KOH, with no mask involved. This etch thins the wafer and stops at the buried boron-doped silicon layer. This step is in 17 shown.
• 27. A plasma etched back etch of the boron-doped silicon layer to a depth of (approximately) 1 μm using a mask 8. This mask defines the nozzle edge. This step is in 18 shown.
• 28. A plasma etch back through the boron doped layer using a mask 9. This mask defines the die and the edge of the chips. At this stage, the chips are separated, but still attached to the glass blank. This step is in 19 shown.
• 29. Peeling the chips from the glass blank. Removing all adhesive, resist, sacrificial and exposed germ layers. This step is in 20 shown.
• 30. Insertion of the printheads into their enclosure, which may be a plastic molding, into which ink channels have been introduced in advance, which supply different ink colors to the corresponding areas of the front surface of the wafer.
• 31. Connect the printheads to their interconnected systems.
• 32. Make the front surface of the printheads hydrophobic or water repellent.
• 33. Fill the finished printheads with ink and test them. A filled nozzle is in 21 shown.

IJ - Uses

The The above-disclosed ink jet printing technology is potential for a wide range of printing systems, including: office printers for color and monochrome operation, short-term use digital printers, high-speed digital printers, Printer for support from offset printing machines, low-cost scanning printers, high-speed printers in page width, notebook computer with built-in printers in page width, portable printer for Color and monochrome operation, color and black-and-white copiers, color and black-and-white fax machines, combined Printing, faxing and copying machines, Label printer, plotter for size Paper sizes, photocopiers, printers for digital photo "minilabs", video printers, photo CD printers, portable printer for PDAs, wallpaper printers, indoor sign printers, billboard printers, Printer for printing on tissue, camera printers and fail-safe, commercial printer orders.

inkjet technologies

The embodiments of the invention use a device of the type of an ink jet printer. Naturally could many different devices are used. Currently far Common inkjet printing technologies are likely to be suitable but most of all.

The The most significant problem with a thermal ink jet is the Power consumption. This is about 100 times as high as the for one High speed operation required and originates from the tools during drop ejection, use the energy inefficiently. This concerns the fast high boiling of water to create a vapor bubble that expels the ink. Water has a very high heat capacity and must overheated in thermal inkjet applications. This leads to a Efficiency of approx. 0.02% of the electrical energy used until the outgoing force pulse of the drop (and the raised surface).

The most significant problem with a piezoelectric inkjet exists in terms of size and the Costs. Piezoelectric crystals have a very small deflection at moderate control voltages and need therefore for every nozzle a big Area. Also, it is such that every piezoelectric actuator with its Control circuit must be connected to a separate substrate. This is at the current limit of about 300 nozzles no major problem per printhead, but a major obstacle in the production of printheads in page width with 19,200 nozzles represents.

Ideally, the inkjet technologies used meet the high demands of camera-integrated digital color printing, as well as other high-quality, high-speed, low-cost printing applications. To meet the requirements of digital photography, New inkjet technologies have been created. The target features include:
Low energy (under 10 watts)
High resolution (1600 dpi or above)
Output in photo quality
Low production costs
Small size (page width times minimum cross section)
High speed (<2 seconds per side).

All these properties can from the ink-jet systems described below with various ones Difficulty levels are achieved or exceeded. From the applicant 45 different inkjet technologies have been developed around for the mass production to provide a wide range of choices. These technologies form part of separate tables in the following table listed Applications transferred to the present applicant.

The Ink jet designs shown here are suitable for one wide range of digital printing systems, from battery-powered digital cameras for single use, over Desktop and network printers right up to commercial printing systems.

For ease of fabrication using a standard process tool, the printhead is designed to be a monolithic 0.5 micron CMOS chip with MEMS post-processing. For color photography applications, the printhead is 100 mm long and has a width that depends on the type of ink jet. The smallest developed print head is the IJ38 with 0.35 mm width and a chip area of 35 mm ² . The printheads each contain 19,200 nozzles plus a data and control circuit.

Of the back Ink is supplied to the printhead through injection molded plastic ink channels. Of the Forming process requires the formation of 50 microns measuring details, the using a lithographically micromachined Use in a standard injection molding tool can be generated. Over through etched the wafer holes flows Ink to the nozzle chambers, the on the front surface of the wafer are made. The printhead is attached to the camera circuit connected by an automated ribbon connection.

Cross reference to others Registrations

The following is a guide to cross-referenced patent applications filed concurrently with the present application and explained below with reference to the following tables when referring to a particular case:

Tables for Drop on demand inkjet

It 11 key features of the basic operation from individual inkjet nozzles turned off. These features largely exclude each other, and can be explained in the form of an eleven-dimensional matrix. The most of 11 axes of this matrix include entries made by the present applicant were developed.

The following tables form the axes of an eleven-dimensional table of inkjet designs.
Actuator mechanism (18 types)
Basic Operation (7 types)
Additional mechanism (8 types)
Actuator reinforcement or modification process (17 types)
Actuator movement (19 types)
Method for refilling the nozzle (4 types)
Method for restricting the return flow through the inlet (10 types)
Nozzle cleaning process (9 types)
Nozzle plate construction (9 types)
Drop ejection direction (5 types)
Type of ink (7 types)

The complete eleven-dimensional table represented by these axes contains 36.9 billion possible Configurations of an ink jet nozzle. While not all of the possible Combinations lead to a useful inkjet technology are many millions of configurations feasible. It is clear that not all possible Configurations explained can be. Instead, specific types of ink jet have been studied in detail. These are designated above with IJ01 to IJ45.

Out These 45 examples are easily other ink jet configurations derive alternative configurations along one or the other several of the 11 axles used. Most of the example IJ01 until IJ45 can in inkjet printheads incorporated, which then have properties that everyone currently available Superior inkjet technology are.

Where The inventors are aware of examples of prior art one or more of these examples in the example columns of the following Tables listed. The sample columns also list the series IJ01 to IJ45. In some cases can a printer be named more than once in a table, namely where he with more than one entry the properties Splits.

suitable Applications include: home printers, office network printers, digital printers for the Short-term use, commercial printing systems, printers for printing fabric, pocket or pocket printer, internet www printer, video printer, Imaging in the field of medicine, wide format printers, notebook PC printers, fax machines, Printing systems for Industrial applications, photocopiers, photography minilabs or minilabs Etc.

The information associated with the above-mentioned eleven-dimensional matrix is set forth in the following tables.

a It will be clear to a person skilled in the art that numerous modifications and / or modifications to the present invention, as in the specific embodiment can be made without being described in detail Deviating scope of the invention. The present embodiment should therefore be considered in all respects as illustrative and not restrictive become.

Claims (6)

An ink jet printhead comprising a plurality nozzle arrangements, wherein each nozzle assembly comprises: (A) a nozzle chamber with a discharge opening an end; (b) a piston of soft magnetic material made and between the nozzle chamber and an ink chamber, wherein the ink chamber is the supply from ink to the nozzle chamber permits; (C) an electrical coil disposed adjacent to the piston and electrically with a nozzle activation signal connected, wherein upon activation of the activation signal, the piston through the spool from an ink loading position to an ink ejecting position is moved, causing the ink ejection from the ink ejection opening becomes. The ink-jet printhead of claim 1 further comprising a made of soft magnetic material anchor plate and wherein the piston is pulled to the armature plate upon activation of the coil becomes. An ink jet print head according to claim 1, wherein said electrical coil within a cavity defined by the piston lies and the cavity in its expansions as a result of the movement of the piston is reduced, the piston also has a series of slots for the Liquid outlet in liquid connection with the cavity and the ink chamber and the slots for the liquid outlet below Pressure in the cavity the ejection of liquid enable. The ink-jet printhead of claim 1 further comprising Spring means to help the provision of the piston from the ink ejecting position to the ink loading position after the ejection of Ink from the ejection port. An ink-jet printhead according to claim 4, wherein said Spring means comprise a torsion spring. An ink-jet printhead according to claim 5, wherein said Torsion spring an arcuate Construction is essentially the same circumferential profile like the piston has.