JP2001519264A - Device for depositing droplets and method for producing the same - Google Patents

Abstract

A piezoelectric printhead or other droplet deposition apparatus has parallel liquid containing channels defined by a base and displaceable walls, and covered by a cover number. The channels each have at least one nozzle for ejecting droplets. Each nozzle may be disposed in the base, the cover then having two ink supply parts spaced lengthwise of each channel on opposite sides of the nozzle. Alternatively two longitudinally spaced nozzles may be provided in the base of each channel. The cover may have a conductive track corrected to wall-displacing electrodes, the points of connection being outside the channels. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a device for depositing droplets, in particular an ink jet printhead, which comprises a channel in communication with a supply of droplet liquid and a hole for ejecting droplets therefrom, wherein at least one channel side has: It is displaceable in response to an electrical signal, thereby causing ejection of a droplet from the channel. FIG. 1a is a cross-sectional view of a channel of a prior art ink jet printhead structure according to WO 92/22429, which is by the applicant and incorporated herein by reference. The piezo-electric ceramic sheet 12 is poled in its thickness direction 17 and formed on one surface by a channel 11 which is joined by a channel wall 13 to two sides parallel to the channel axis. With the electrodes 23 formed on both sides of each wall 13, an electric field is applied to the piezoelectric material of the walls, causing them to warp in a shear mode transverse to the channel axis. A pressure wave is generated in the ink, thereby causing the ejection of a drop of ink. These principles are well known to those skilled in the art, for example, from EP-A 0 364 136 by the applicant and incorporated herein by reference. Channels 11 are closed along one side parallel to the channel axis by the surface of cover 14 having conductive tracks 16 at the same pitch spacing as the ink channels formed thereon. A solder bond 28 is formed between the track 16 and the electrode 23 in the channel wall, thereby securing the cover to the base and creating an electrical connection between the electrode and the track in a single step. Let it. The electrodes and tracks are then passivated to prevent them from being subsequently eroded by the ink.

[0002] As shown in FIG. 1 b, it is a cross-sectional view taken along the longitudinal axis A of only one channel of the prior art printhead of FIG. 1 a but having respective ink ejection nozzles 22. The nozzle plate 20 is provided on the front side of the sheet 12, while the ink manifold 26 is defined on the rear side by the manifold structure 21.
The track 16 is typically led behind the cover 14 for connection to a drive circuit embodied in a microchip 27 which is then driven by a signal received via the input track 18. In this type of printhead, the channel walls, and especially the electrodes formed thereon, are often passivated so as to be protected from subsequent corrosion by the ink.
In this regard, WO 95/0782, which is incorporated herein by reference.
See issue 0. However, in the device described above, this conventional passivation prior to installation of the cover would hinder the formation of a solder joint between the electrode and the track. On the other hand, passivation after the cover has been applied is only applicable from the end of the channel, resulting in poor quality coating between the electrode and the track, especially at the midpoint of the channel away from the end of the channel It's just The present invention has, as an object, a printhead structure that retains the advantages of the connection associated with the conductive tracks formed on the cover of a conventional structure and that is subject to passivation.

The invention therefore comprises, in one aspect, at least one channel having a means for communicating with the supply of droplet liquid as well as a hole for the ejection of droplets; the channel is combined with actuation means The channel wall is coupled to at least one side parallel to the channel axis; the actuating means causes a displacement of the channel wall in response to an electrical signal, thereby causing a droplet to be ejected from the channel; Coupling on a further side parallel to the channel axis, the cover surface forms thereon at least one conductive track for sending an electrical signal to the actuating means, the electrical contact between the track and the actuating means Consists of a device for depositing droplets outside the channel. Since the only point of electrical connection between the track and the actuation means according to the invention is outside the channel and thus out of contact with the ink, which has the potential for its corrosive action, passivation of this point Is no longer needed. The channel itself can then be passivated as usual via the open top of the channel. As such, the cover can be mounted and electrical contact is established between the conductive tracks on the cover and the actuation means associated with the channel wall. Even for printheads that do not require passivation, due to the type of ink designed to be fired, the electrical contacts outside of the channel according to the present invention are the same as in the prior art device of FIGS. It appears to be less fatigued than the solder length of the channel length. A corresponding method according to the first aspect of the invention comprises a method of manufacturing a device for depositing droplets, the method comprising forming at least one open-ended channel in a base component and connecting the channel to a channel axis. Coupled to at least one side parallel to the channel, wherein the channel wall is combined with an actuating means for displacing the channel wall in response to an electrical signal, thereby effecting ejection of droplets from the channel; Closing the channel on a further side parallel to the axis, the cover surface having at least one conductive track formed thereon for sending an electrical signal to the actuating means; and conductive at a point outside the channel. Electrically connecting the truck and the operating means. Advantageously, the step of closing the channel provides an electrical connection between the conductive track and the actuation means, thereby simplifying the manufacturing method.

[0004] A first aspect of the present invention also comprises a droplet depositing device comprising a bottom sheet of a device for depositing droplets that have been poled with a piezo substance, which comprises: And is formed by a plurality of parallel and straight open channels spaced from one another in an array direction perpendicular to the length of the channel and facing the surface of the sidewall and the bottom extending between the sidewalls. A bottom sheet of piezo material respectively defined by said top surface sheet facing said bottom surface of said channel and connected at its top to said channel close to said channel; ejection of droplets of liquid therefrom A nozzle for communicating with said channel for each of said nozzles; comprising connecting means for connecting said channel to a source of liquid for depositing droplets; The channel is formed by a forward portion in which the electrodes are provided on at least one opposing side of the side wall defining the channel, thereby forming a shear mode actuator for effecting ejection of droplets from the channel. And each channel is formed by a rear portion having an electrically conductive coating in electrical contact with at least one electrode on the channel-facing side of the front portion sidewall, the sealing means comprising a front portion and a rear portion. And a device further comprising a conductive track formed on the surface of the top sheet coupled to the side wall, the conductive track being electrically conductive of the rear portion. It consists of a device for depositing droplets in electrical contact with the coating.

[0005] A corresponding method comprises forming a bottom sheet having a layer of piezo material poled in a direction perpendicular to the sheet; a plurality of sheets spaced apart from each other in an arrangement direction perpendicular to the length of the channel. Forming parallel, open-top channels of each other, each channel being defined by facing a sidewall and a bottom surface extending between the sidewalls, each channel further having a forward portion and a rearward portion. Forming an electrode on at least one opposing side wall of a side wall defining a forward portion of each channel, thereby forming a shear mode actuator for ejecting droplets from the channel; And forming an electrically conductive coating on the rear portion of each channel in electrical contact with the respective electrode; formed by conductive tracks thereon Providing a top sheet having a surface; and bonding the surface of the top sheet having a conductive track thereon to the side wall so as to be close to the channel at the top thereof; Establishing electrical contact with the conductive coating; providing sealing means separating the front and rear portions of each channel. A second aspect of the invention is directed to at least one vertical and open-top droplet liquid channel defined by facing the vertical sidewalls and a bottom and vertical surface extending between the sidewalls; Means for applying an electric field to the piezo material on one side wall and thereby displacing the wall with respect to said vertical channel so as to eject droplets from the channel; and a cover closing the open vertical top side of the channel. A device for depositing droplets, wherein said bottom and vertical surface of the channel is formed by a hole for droplet ejection, and a cover incorporates two openings for the supply of droplet liquid; The opening consists of a device for depositing droplets spaced along channels on both sides of the hole.

[0006] This structure also applies to the production of known printheads, in particular WO 91/17051.
No., which belongs to Applicant and is cited by reference.
It simplifies it of the type of "top shooter". FIG. 2 shows a cross-sectional view along the channel of this conventional printhead, which has features corresponding to FIG. 1 indicated by corresponding reference numerals. The droplet ejection results from the nozzle 22 formed in the cover component 60 of the channel, while the droplet liquid is supplied to the channel via an opening 33 formed in the base of the channel, and the opening comprises a piezoelectric channel. Are generally sequentially connected to ink supply conduits (not shown) formed in a base component 35 that is separate from the components 12 of the base. According to the invention, a hole in communication with the droplet ejection orifice is formed in the bottom surface of the channel, whereby the cover component arranges an opening for the supply of ink to the channel. Other separate base components are therefore no longer needed. A third aspect of the present invention is directed to at least one vertical and open-top droplet liquid channel defined by facing a vertical sidewall and a bottom and vertical surface extending between the sidewalls; Means for applying an electric field to the piezo material at at least one side wall, thereby effecting wall displacement with respect to said vertical channel so as to eject droplets from the channel; and opening the channel. A device for depositing a droplet comprising a cover closing the side of a vertical top, wherein said bottom and vertical surface of the channel is formed by two holes for droplet ejection, further comprising: A device for depositing droplets spaced along a channel. Such a structure is a P-type structure which belongs to the applicant and is hereby incorporated by reference.
The apparatus of the CT application No. PCT / GB98 / 01495 brings the aforementioned advantage of reducing the number of components. The corresponding method claims are also included in the invention, and other embodiments are set forth in the other independent claims. Further advantageous aspects of the invention are shown in the description, the drawings and the claims. All claim descriptions are considered to be incorporated herein unless otherwise indicated above.

The present invention will be described, for example, with reference to the following figures. FIG. 3 is a cross-sectional view taken along the channel axis of the printhead according to the first embodiment of the first aspect of the present invention. 4a and 4b show details of the rear part of the print head of FIG. 3 before and after the cover is attached, respectively. FIG. 5 is a cross-sectional view taken along a channel axis of a printhead according to a second aspect of the first aspect of the present invention. FIG. 6 is a cross-sectional view taken along the channel axis of a printhead incorporating both the first and second aspects of the present invention. FIG. 7 is a cross-sectional view taken along a channel axis of a printhead according to a second embodiment of the second aspect of the present invention. FIG. 8 is a detailed perspective view of the distal end of the piezoelectric body of the printhead of FIG. 9 and 10 are a cross-sectional view and a detailed cross-sectional view, respectively, of another embodiment of the printhead shown in FIG. FIG. 3 shows a printhead according to a first embodiment of the first aspect of the present invention,
And 2 conventional printheads are denoted by a common reference number. As in conventional devices, a piezo-electric ceramic body 12 that is poled in its thickness direction is formed by channels 11 separated by channel walls 13. As is known from the above-mentioned EP-A 0 364 136, the electrode 23 comprises:
A groove 100 formed along each wall 13 of the ink-containing channel 11 and further
Along the rear surface 130 of the body. In addition, cover 14, channel 11
There is provided a surface 15 near each open side of the nozzle, a nozzle plate 20 having nozzles 22 for the ejection of droplets, and a manifold for the supply of ink into channels in the form of lateral cuts in the body 12. The surface 15 of the cover 14 has tracks 16 formed thereon (the preferred method is well known), which in turn is a microchip 27 (schematically depicted and not shown in FIG. 3). , Which in turn receives an input signal from input track 18. Details of the rear of the printhead before the cover is attached are shown in FIG. 4a, where the passivation layer 140 (not shown in FIG. 3, but shown in FIG. 3 and 4a) (indicated by the solid diagonal lines) and separates along the rear groove 100. In contrast to the prior art structures, the passivation takes place before the attachment of the cover, and is advantageously WO 95/0782 belonging to the applicant and hereby incorporated by reference.
According to the method described in No. 0.

[0008] The mechanical connection between the body and the surface 15 of the cover 14 is achieved by an adhesive layer 160, which preferably belongs to the applicant and is referred to in WO95 / According to the method described in WO 04/6586, it is applied to the distal surface of the wall 13 in the region of the channel 11 before the assembly of the cover and the body. FIG. 4b
Delineates the assembled printhead and the adhesive bond is indicated at 220. This connection is in fact stronger and has a longer fatigue life than the corresponding solder connection of the prior art structure described above. The electrical connection between the conductive track 16 on the cover and that portion of the electrode 23 of the rear groove 100 is made of a protruding, deformable conductive material such as solder attached to the distal end 180 of the track 16. 170. In assembling the cover to the body, the projections 170 come into contact with the electrodes 23 and are deformed, as shown in FIG. 4b, thereby providing effective electrical contact 200 between the electrodes 23 and the tracks 16. Bring. Sealing paste or high viscosity adhesive beads 190 are also applied to form an ink seal 210 between the ends of the ink channels 11 and the electrical contacts 200 during assembly. This seal protects the electrical contact from subsequent corrosion by the ink. Preferably, the seal is located across the free end 150 of the passivation layer 140, thereby preventing seepage of the ink under the passivation layer from otherwise attacking the electrode material 23.

FIG. 5 shows a second embodiment of the first aspect of the present invention. The ceramic piezo electric body 290 is formed by channels 11 that are poled in thickness and separated by channel walls 13 as in the conventional embodiment, the channel walls then being formed on each side by the electrodes 23. Having. However, the ejection of ink results from a centrally located nozzle 320 in the nozzle plate 330 that communicates with the channel either directly through the cover 350 or through a gap 340 formed in the cover as shown. The body 290 is further formed with two manifolds 310 for feeding from both ends of the channel, as indicated by arrows 300. A further structure (not shown) would supply ink from the reservoir to the manifold. This "dual-end" printhead construction is disclosed in WO 91/17051, belonging to the Applicant and incorporated herein by reference, and the "
It has the advantage of lower operating voltage than the "single-ended" configuration. In addition, the structure of the base 290 is more suitable for fabrication by molding, a technique that is potentially more attractive in terms of manufacturability than the conventional sawing technique described in the aforementioned EP-A 0 364 136. . Conductive tracks 370 formed on the surface of cover 350 facing body 290
The connection of the channel electrode 23 to, however, has already been described with respect to FIGS. 3, 4a and 4b and is located in a groove 360 formed on one side of the body 290. Similarly, the channel itself (its channel walls are passivated before assembly)
The cover 350 is attached to the piezo-electric ceramic body by a conventional adhesive bond (not shown) at its end 380 in the area of the body and not occupied by the electrical connection. The nozzle 320 can be formed on the cover 350 itself to minimize the distance ink travels from the channel body 11 to the outlet of the nozzle 320, thereby reducing pressure loss and thus reducing the speed of droplet ejection. . Advantageously, the nozzle is formed by laser ablation, for example as described in WO 93/15911, which is hereby incorporated by reference, for which purpose the cover is generally of the order of 50 μm in thickness. It can be made from a material that can be ablated, preferably a polymer such as polyimide, polycarbonate, polyester or polyetheretherketone.

[0010] The hardness of a cover plate formed from such an easily ablatable material can be increased by applying a harder material coating to the inner and outer surfaces of the ablatable cover plate. Particularly suitable for this purpose is silicon nitride, which can also be used as a passivating coating in the process of WO 95/07820 mentioned above, is deposited as a smooth coating suitable for the subsequent application of a non-wetting coating, and The conductivity will not short the electrodes of adjacent channels. Placed on both sides of the polyimide cover and each about 5% of that of the cover
The two layers of this material, having a thickness of 2.5 μm for a 50 μm thick cover, generally have a flexural stiffness by a factor of 5-10 (based on standard composite beam theory and about The value of the Young's modulus for a hard material that is 100 times larger, as well as good adhesion between the hard and polymer materials). These thin layers do not have a noticeable effect on the ease with which the cover plate is ablated to form the nozzles, especially if the material of the layers themselves can be ablated to some extent. In broad terms, a cover plate for an inkjet printer is
A first easily ablatable material having a further layer bonded on its opposite side, the further layers each having a hardness of at least a first order of magnitude greater than that of the first material as well as a first Of a material having at least a first order of magnitude less thickness than that of the layer. Referring to FIG. 6, a printhead incorporating both the first and second aspects of the present invention is shown. The piezo-electric ceramic body 400 is formed by a channel 11, a channel separation wall 13 and an electrode 23, which are supplied with an activation signal via a conductive track 410 connected to a driving circuit (not shown). However, unlike the conventional mode, the ejection of the droplet is caused by the closed and bottom surface 440 of the channel
5 arises from the nozzle 420 communicating with the hole 430 formed at 0, which is in contrast to FIG. 5 where the nozzle 320 is located on the cover 350 which closes the open and top side of the channel 11. Molding is also the preferred method of manufacturing the body 400 with the channel, and the arrangement of FIGS. 4a and 4b is also used for the electrical connection between the electrode 23 and the conductive track 410. The communication holes 430 can also be formed during the molding process or can then be formed, for example, by means of a laser. Cover 450 no longer incorporates the nozzles, but is instead formed by ink inlet 460. This arrangement has fewer components than the previously discussed embodiment and has significant manufacturing advantages. Alternatively, the ink supply opening can be formed in a component having a channel, for example, at a channel end.

The printhead of FIG. 7 also uses a cover component 500 having ink inlets 520, 522 and 524 located midway and at both ends of the channel 11 formed in the piezoelectric body 530. The channel wall has a gap 540
Are separated into two portions 550, 560 provided by openings 520, 522 and 522, 524 respectively.
Each electrode 570, 58 driven by a drive circuit (not shown) via 60
0 operates independently. For each portion, a communication hole 630 formed in the bottom surface of the channel at a point intermediate between the respective inlets for that portion;
Each nozzle 610, 620 is provided which communicates with the portion of the channel 11 via 640 and is formed in the nozzle plate 615. These structures are described in co-pending UK Patent Application No. 9710530.8, which belongs to the Applicant and is incorporated herein by reference, and by providing a “double-ended” ink supply to each channel section. This results in a printhead having two parallel rows of compact, independently operable printing elements having a reduced operating voltage per unit droplet ejection speed and yet being compact. Unlike the first embodiment, the conductive tracks 650, 660 that electrically connect the channel electrodes to the drive chip are advantageously provided by the same process in which the electrodes 570, 580 are deposited on the channel walls, by the piezoelectric body itself. Formed on top. This arrangement is known from EP-A 0 397 441 belonging to the applicant and cited herein by reference, and is therefore not described here in further detail. Connections between tracks 650, 660 and drive chips 590, 600 can be achieved by any conventional method, including wire bonding or gold ball connections.

In addition to the piezoelectric body 530 being moldable and having obvious manufacturing advantages, the method also allows the end of the channel 11 to be formed as depicted in FIG. 8, ie, from the top surface 720 of the body. Channel wall 730 and the bottom and vertical surface 7 of the channel
It has a smooth continuous boundary 700 to both of the ten. This in turn avoids discontinuities in the subsequently deposited electrode material as well as a combination of heating effects that may have a detrimental effect on the operating life of the entire printhead. Alternatively, the channels may be formed of piezoelectric components by sawing using a disk cutter as described, for example, in EP-A-0 309 148 and depicted in the cross-sections and detailed cross-sections of FIGS. it can.
It is noted that the depth of the channel 11 terminates further at each end, as shown at 800, and the piezoelectric channel wall defined between adjacent sawed channels 11 has two active portions. 550, 560. However, the cut in the electrode on the channel wall at the position between the two parts,
Ensure that each wall in the active portion can be operated independently by a signal provided via electrical input 820. This cut can be achieved, for example, by masking while the metal plating is being deposited or by removing the plating with a laser. The connection between the electrodes on the channel wall and the electrical input 820 is not shown in detail, but can be achieved by any of the well-known techniques, and the area 9 behind the channel 11
Wire bonding between tracks formed by shallow "ending" grooves formed at 00 (described in the aforementioned EP-A 0 364 136) or between conductive tracks formed in an area 900 on the surface of the piezoelectric sheet itself. (E.g., anisotropic conductive adhesives) (described in EP-A 0 399 441). As in the embodiment of FIG. 7, each channel 11 has openings 520, 522, circulating through each channel portion for the purpose of supplying ink to the active portion of each channel and optionally cleaning the ink as is generally known. Closing along the two active portions 550, 560 of the cover component 500 with suitable length portions 820, 830 also formed by 540. The opening can be positioned to define the edge of the active portion, as in the case of opening 522, in which case manufacturing is simplified. In the example shown, the width of the cover opening 552 and the length portions 820, 803 closing the cover are of the same order of magnitude, typically 2 mm.

[0013] The ejection of ink from each active portion also goes through holes that communicate the channels with the opposite surface of the piezoelectric component (sheet 860) to which the channels are formed. In this embodiment, these holes are provided in slots 840, 850 extending some distance in the longitudinal direction of the channel (typically 200 μm) so as to leave some room for the arrangement of the respective nozzles 870, 880 in the nozzle plate 890. Take shape. Offset of the nozzles may be caused by adjacent channels, such as in a "shared wall" printhead of the type depicted (this is commonly known, for example, from EP A0376 and therefore will not be discussed in further detail). This is generally necessary whenever simultaneous droplet ejection from the camera is not possible. The printhead according to the invention can also be manufactured in a modular format as described in the aforementioned WO 91/17051, wherein each module is formed at its opposite end surface for a respective channel part, and the modules are connected to each other. Upon mating, additional channels are formed between each set of mated modules. In these arrangements, each channel part is
It includes at least a portion of the slot formed in the base of the channel, and furthermore, a sufficient number of slots to accommodate the nozzle, even if the mated set of modules and their respective slot parts are not perfectly aligned. It should be long enough to maintain the overlap between half of the slots. As in the conventional manner, the nozzles 870, 880 are provided with a nozzle plate 890.
Piezoelectric sheet 86 as depicted, for example, to provide a suitably large area for engagement of a capping and / or wiping mechanism.
0 can extend over substantially the entire length.

It is to be understood that the present invention has been described by way of example only and that a wide variety of modifications may be made without departing from the scope of the invention. Features set forth in the concept of the first aspect of the invention are equally applicable to the second aspect and vice versa. For example, the piezoelectric channel walls can be polarized in opposite directions perpendicular to the plane of the channel axis, as is known, for example, from EP-A 0 277 703, which is incorporated herein by reference. Alternatively, the polarization of the channel walls can be made parallel to the plane of the channel axis by means of the electrodes themselves formed in the channel, as is known, for example, from EP-A-0528647. Alternatively, it is not required that all channels of the printhead be capable of drop ejection, and active channels capable of drop ejection are described, for example, in the aforementioned European Patent No. A
As described in U.S. Pat. No. 2,277,703, an inert so-called “dummy” channel allows alternating printheads.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1a is a cross-sectional view of a channel of a prior art inkjet printhead structure according to WO 92/22429. b is a cross-sectional view taken along the longitudinal axis A of only one channel of the prior art printhead of FIG. 1a.

FIG. 2 is a cross-sectional view along a channel of a conventional print head.

FIG. 3 is a cross-sectional view taken along a channel axis of the printhead according to the first embodiment of the first aspect of the present invention.

FIGS. 4a and b show details of the rear part of the printhead of FIG. 3 before and after attachment of the cover, respectively.

FIG. 5 is a sectional view taken along a channel axis of a printhead according to a second aspect of the first aspect of the present invention.

FIG. 6 is a cross-sectional view taken along the channel axis of a printhead incorporating both the first and second aspects of the present invention.

FIG. 7 is a cross-sectional view taken along a channel axis of a printhead according to a second embodiment of the second aspect of the present invention.

8 is a detailed perspective view of the distal end of the piezoelectric body of the printhead of FIG.

FIG. 9 is a cross-sectional view of another embodiment of the printhead shown in FIG.

FIG. 10 is a detailed cross-sectional view of another aspect of the printhead shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Channel 12 Piezoelectric ceramic sheet 13 Channel wall 14 Cover 15 Cover surface 16 Conductive track 17 Thickness direction 18 Input track 20 Nozzle plate 21 Manifold structure 22 Nozzle 23 Electrode 26 Ink manifold 27 Micro chip 28 Solder connection 33 Opening 60 Channel Cover component 100 groove 130 back of body 140 passivation layer 150 end of passivation layer 160 adhesive layer 170 protrusion 180 end of track 200 electrical contact 210 ink seal 220 adhesive bond 290 ceramic piezo electric body 310 manifold 320 nozzle 330 nozzle Plate 340 Clearance 350 Cover 360 Groove 380 End of body 400 Piezoelectric ceramic body 410 Conductive track 420 Nose 430 Hole 440 Channel bottom surface 450 Cover 460 Opening 500 Cover component 520 Opening 522 Opening 524 Opening 530 Piezoelectric body 540 Gap 550 Part 560 Part 570 Electrode 580 Electrode 590 Driving chip 600 Driving chip 610 Nozzle 620 Nozzle 620 Nozzle 6 Hole 650 Conductive track 660 Conductive track 700 Transition 710 Channel bottom surface 720 Body top surface 730 Channel wall 800 Channel depth 810 Cut 820 Electrical input 830 Length direction 840 Slot 850 Slot 860 Piezoelectric sheet 870 Nozzle 880 Nozzle 890 nozzle plate 900 area behind channel

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IS, JP, KE, KG , KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZW (72) Inventor Omagh, Salhadin Cambridge CB 40 UK Science Park, Saar Inside Technology Limited (72) Inventor Temple, Stephen Cambridge CB, UK 40 XR Science Park, Saar Technology Limited F-term (reference) 2C057 AF66 AF93 AG12 AP02 AP22 AP23 AP25 AQ03 AQ10 BA03 BA14

Claims (58)

[Claims] 1. At least one vertical and open-top droplet liquid channel defined by facing a vertical sidewall and a bottom and vertical surface extending between the sidewalls; at least one sidewall. Means for applying an electric field to the piezo material and thereby displacing the wall with respect to said vertical channel so as to eject droplets from the channel; and a cover comprising a cover closing the open vertical top side of the channel. The bottom and vertical surface of the channel is formed by a hole for droplet ejection, the cover further incorporates two openings for the supply of droplet liquid, and the opening comprises: A device for depositing droplets spaced along channels on both sides of the hole. 2. Apparatus according to claim 1, wherein the supply openings are equally spaced on both sides of the hole. 3. The apparatus of claim 1 wherein the bottom and vertical surface of the channel is formed by at least two holes, the holes being spaced along the channel. 4. The apparatus of claim 3 wherein the cover incorporates droplet supply openings spaced along the channel so as to lie on both sides of each hole. 5. The apparatus according to claim 1, wherein the piezoelectric material deforms in shear mode when subjected to an electric field. 6. The device according to claim 1, wherein the electrode is formed on a surface of the channel wall facing the channel. 7. The apparatus of claim 6, wherein the electrode is also formed on the channel wall on a surface opposite the surface of the channel wall facing the channel. 8. Apparatus according to claim 1, wherein said channel wall is displaceable in response to an electrical signal in a direction perpendicular to the axis of the channel. 9. The apparatus of claim 1, wherein said bottom and vertical surface are defined by a base, said base and said vertical side wall being integral. 10. Apparatus according to claim 1, comprising a plurality of vertical channels arranged parallel to one another. 11. At least one vertical and open-top droplet liquid channel defined by facing longitudinal sidewalls and a bottom and longitudinal surface extending between the sidewalls; droplet liquid in the channel. Means for applying an electric field to the piezo material at at least one side wall, thereby effecting wall displacement with respect to said vertical channel so as to eject droplets from the channel; and An apparatus for depositing droplets comprising a side closing cover, wherein said bottom and vertical surface of the channel is formed by two holes for droplet ejection, the hole further along the channel. A device for depositing droplets that are spaced apart. 12. The apparatus of claim 11 wherein the means for supplying the droplet liquid includes a supply opening in the cover spaced along the channel to be on both sides of each hole. 13. The apparatus of claim 11, wherein the piezoelectric material deforms in shear mode when subjected to an electric field. 14. The device according to claim 11, wherein the electrode is formed on the channel-facing surface of the channel wall. 15. The apparatus of claim 14, wherein the electrodes are also formed on the channel wall opposite the surface of the channel wall facing the channel. 16. Apparatus according to claim 11, wherein said channel wall is displaceable in response to an electrical signal in a direction perpendicular to the axis of the channel. 17. The apparatus according to claim 11, wherein said bottom and vertical surfaces are defined by a base, said base and said vertical side walls being integral. 18. The apparatus according to claim 11, comprising a plurality of vertical channels arranged parallel to one another. 19. A body comprising a piezoelectric material and having at least one vertical, open-topped channel facing the bottom and vertical surfaces extending between the vertical sidewalls and the sidewalls. Forming a hole in the bottom and vertical surface of the channel for the ejection of the droplet liquid; applying an electric field to the piezoelectric material on at least one of the walls, thereby removing the electric field from the channel. Providing means for effecting displacement of the wall in response to said vertical channel to eject a droplet; two spaced apart along the channel on both sides of the hole A method of manufacturing a device for depositing droplets, comprising closing an open vertical top surface of a channel with a cover having a droplet liquid supply opening. 20. The method of claim 19, including the step of forming said bottom and vertical surfaces and said vertical sidewalls so as to be integral with one another. 21. Providing a body of piezoelectric material and removing material from the body;
21. The method of claim 20, including the step of forming said channel in said body. 22. Providing a body in the form of a sheet having first and second opposing surfaces; removing material from the first surface of the body, thereby forming a channel; 22. The method of claim 21 including forming a hole in the surface of the sheet, wherein the hole is in communication with said second surface of the sheet. 23. The method of claim 24 including the step of polarizing the piezoelectric material of the sheet in a direction perpendicular to said first and second surfaces. 24. A body comprising piezoelectric material and having at least one vertical, open-topped channel facing the bottom and vertical surfaces extending between the vertical sidewalls and the sidewalls. Forming two holes in the bottom and vertical surface of the channel for the ejection of droplet liquid, the holes being spaced along the channel; Providing at least one means for applying an electric field to the piezoelectric material, thereby effecting wall displacement in response to said vertical channel to eject droplets from the channel; A method for manufacturing a device for depositing droplets, comprising a step of closing a top surface. 25. Closing the open and vertical top side of the channel with a cover incorporating droplet supply openings spaced along the channel so as to be located on both sides of each hole. 25. The method of claim 24, comprising: 26. The method of claim 24 or claim 25 including the step of forming said bottom and vertical surfaces and said vertical sidewalls to be integral with one another. 27. The method of claim 26, comprising providing a body of piezoelectric material and removing material from said body, thereby forming said channel in said body. 28. Providing a body in the form of a sheet having first and second opposing surfaces; removing material from the first surface of the body thereby forming a channel; 25. The method of claim 24, comprising forming the two holes in a surface, the holes communicating with the second surface of the sheet. 29. The method of claim 28, including the step of polarizing the piezoelectric material of the sheet in a direction orthogonal to said first and second surfaces. 30. An apparatus for depositing a droplet having at least one channel having means for communicating with a supply of droplet liquid and a hole having a hole for ejecting the droplet, wherein the channel is associated with an actuating means. Coupled to at least one side parallel to the channel axis by the channel wall being provided, the actuation means effecting displacement of the channel wall in response to an electrical signal, thereby effecting ejection of droplets from the channel; Coupled to a further side parallel to the channel axis by a surface of the cover, the surface of the cover forming at least one conductive track thereon for sending an electrical signal to the actuating means, wherein the track and the actuating means The point of electrical connection between is a device that deposits droplets outside the channel. 31. A base component having at least one open-ended channel formed therein and coupled to the channel on at least one side parallel to the channel axis, wherein the channel wall is displaced in response to an electrical signal. And closing the channel on a further side parallel to the channel axis by the cover surface, the cover surface transmitting an electrical signal to the actuation means. Forming at least one conductive track thereon for feeding; and electrically connecting the conductive track to the actuation means at a point outside the channel. . 32. The method of claim 31, wherein the step of closing the channel electrically connects the conductive track and the actuation means. 33. Apparatus or method according to any one of claims 30 to 32, wherein the point of electrical connection is sealed from entry of droplet fluid from the channel. 34. An area adjacent to said channel having an electrically conductive coating in electrical contact with actuation means associated with at least one channel wall of said channel, wherein said conductive track is electrically conductive. 34. An apparatus or method according to any one of claims 30 to 33 in electrical contact with the conductive coating. 35. The apparatus or method of claim 34, wherein said area is a groove. 36. The apparatus or method of claim 35, wherein the grooves are shallower than the channels. 37. Apparatus or method according to claim 35 or 36, wherein the groove is co-linear with the channel. 38. Apparatus or method according to any one of claims 31 to 33, wherein the groove is sealed by sealing means against the entry of droplet fluid from the channel. 39. Apparatus or method according to any one of claims 30 to 34, wherein the electrical contact is made by a deformable conductive material sandwiched between the electrically conductive coating and the conductive track. 40. The apparatus or method of claim 39, wherein the deformable conductive material is wax. 41. Apparatus or method according to any one of claims 30 to 40, wherein a protective coating is applied to the channel wall. 42. The apparatus of claim 41, wherein said electrically conductive coating further extends beyond at least one channel facing surface of the channel wall, and wherein a protective coating is applied to said electrically conductive coating. Or method. 43. The apparatus or method of claim 41, wherein according to claim 34, the protective coating terminates in the area adjacent to the channel. 44. The method according to claim 31, wherein a protective coating is applied to at least one of the channel walls before closing the channel with the cover. 45. The method according to claim 43, further comprising the step of masking the point of electrical connection between the conductive track and the actuation means before applying a protective coating to at least one of the channel walls. Method. 46. The apparatus or method of claim 38, wherein said sealing means extends beyond the end of the protective coating in the area adjacent to the channel. 47. Apparatus or method according to any one of claims 30 to 46, wherein the top of the channel wall is attached to the surface of the cover by a non-conductive bond. 48. The apparatus or method of claim 47, wherein the non-conductive bond is an adhesive bond. 49. Apparatus or method according to any one of claims 30 to 48, wherein a plurality of channels are arranged, the channels being parallel to each other and defining a channel wall therebetween. 50. The channel wall is displaceable in response to an electric signal in a direction perpendicular to the channel axis and parallel to the channel arrangement direction.
Apparatus or method. 51. Apparatus or method according to any one of claims 30 to 40, wherein the channel wall comprises a piezoelectric material to which the electrical signal is applied. 52. The apparatus or method of claim 51, wherein said piezoelectric material deforms in shear mode upon receiving said electrical signal. 53. The apparatus or method of claim 52, wherein the electrodes are formed on the channel-facing surface of the channel wall, and the piezoelectric material is polarized in a direction perpendicular to both the array direction and the channel axis. . 54. Apparatus or method according to any one of claims 30-53, wherein the body comprises a sheet of piezoelectric material and the plurality of channels are formed on one surface of the sheet. 55. The apparatus or method of claim 54, wherein the piezoelectric material is polarized in a direction perpendicular to the surface of the sheet. 56. Apparatus or method according to any one of claims 30 to 55, wherein said cover is formed by an opening for the supply of droplet liquid into said channel. 57. A side wall formed by a plurality of parallel, open-topped channels poled in a direction perpendicular to the sheet and spaced from each other in an alignment direction perpendicular to the length of the channel. And a bottom sheet of piezoelectric material, each defined by facing a surface of a bottom extending between the side walls; facing the bottom surface of the channel and bonded to the side wall at a top thereof near the channel. A respective nozzle in communication with the channel for the ejection of a droplet of liquid; a droplet comprising connection means for connecting the channel and a source of liquid for depositing the droplet. Wherein each channel is provided on at least one opposing side of a side wall defining the channel, and wherein Each channel is formed by a forward portion forming a shear mode actuator for effecting the ejection of droplets from the flow channel; and each channel is provided with at least one electrode on the channel-facing side wall of the forward portion. Formed by a rear portion having an electrically conductive coating in electrical contact, sealing means separates the front and rear portions, and a device is provided on the surface of the top sheet coupled to the side wall. An apparatus for depositing droplets, further comprising a conductive track formed thereon, wherein the conductive track is in electrical contact with the electrically conductive coating of the posterior portion. 58. Forming a bottom sheet having a layer of piezo material poled in a direction perpendicular to the sheet; a plurality of parallel and spaced apart arrays arranged in a direction perpendicular to the length of the channel. Forming top open channels, each channel defined by facing a side wall and a bottom surface extending between the side walls, each channel further having a front portion and a rear portion; Forming electrodes on at least one opposing side wall of the side wall defining the forward portion of the channel, thereby forming a shear mode actuator for effecting droplet ejection from the channel; and each channel Forming an electrically conductive coating in electrical contact with the respective electrode on the rear portion of the substrate; having a surface formed by conductive tracks thereon Providing a top sheet having conductive tracks thereon such that the top sheet is close to the channels at the top thereof; and bonding the tracks to a respective electrically conductive coating of each channel. Establishing a contact between the front and rear portions of each channel. A method of manufacturing a device for depositing droplets comprising the steps of: