HK1065980A - Fluid ejector apparatus and methods - Google Patents

Description

Fluid ejection device and method

Technical Field

The present invention relates generally to fluid ejection devices and methods.

Background

In the past decade, substantial progress has been made in the micromanipulation of fluids in the field of electronic printing technology, such as that employing ink jet printers. Currently, a variety of high efficiency inkjet printing systems have been employed that can dispense ink in a quick and accurate manner onto paper or other relatively flat media such as envelopes or labels.

Inkjet printing systems typically employ a platen onto which paper or other relatively flat, flexible media is delivered by friction using various motors, gears, guide wheels, axles and mounts. The media transport mechanism generally provides a motion that can remove media from a tray and feed it through the print zone by propelling, pulling, or carrying the media. The print zone generally positions the media relative to the printhead. An almost flat print zone is generally used because the two-dimensional area of a typical nozzle layout can result in varying throw distances if the media or media carrier is too bowed. A carriage to which one or more print cartridges are secured, typically supported by and naturally advanced along a slide bar or similar mechanism within the system, where the print cartridge has one or more fluid ejector heads to allow the carriage to translate back and forth or scan back and forth over the media. When a row of dots has been completed, the media is moved the appropriate distance along the media axis in preparation for the next row.

The ability to dispense discrete deposits of material onto media surfaces of different shapes and pliability at designated locations using fluid ejectors and fluid dispensing systems opens up a variety of application operations that are currently not practical.

Drawings

FIG. 1a is a perspective view of a fluid ejector head in one embodiment of the present invention;

FIG. 1b is a perspective view of a fluid ejector head in an alternative embodiment of the invention;

FIG. 2a is an isometric cross-sectional view of a fluid ejector body in an alternative embodiment of the invention;

FIG. 2b is a partial perspective view of the fluid ejector body of FIG. 2a in accordance with an embodiment of the present invention;

FIG. 3 is a cross-sectional view of a fluid ejector body in an alternative embodiment of the invention;

FIG. 4 is a cross-sectional view of a fluid ejector body in an alternative embodiment of the invention;

FIG. 5 is a cross-sectional view of a fluid ejector body in an alternative embodiment of the invention;

FIG. 6a is a perspective view of a fluid ejector cartridge in an embodiment of the invention;

FIG. 6b is a perspective view of a fluid dispensing system in an embodiment of the present invention;

FIG. 7 is a flow chart of a method of manufacturing a fluid ejector head in an embodiment of the present invention;

FIG. 8 is a flow chart of a method of using the fluid dispensing system in accordance with an embodiment of the present invention;

FIG. 9a is a perspective view of an article manufactured using an embodiment of the present invention;

FIG. 9b is a perspective view of an article manufactured using an embodiment of the present invention;

FIG. 9c is a perspective view of an article manufactured using an embodiment of the present invention.

Detailed Description

Referring to FIG. 1a, one embodiment of the present invention is shown in perspective view. In this embodiment, fluid injector head 100 includes a fluid injector body 120 adapted for insertion into closed media opening 108. Fluid ejector head 100 also includes a nozzle 130 located on fluid ejector body 120 and fluidly connected to fluid channel 140. Fluid ejection actuator 150 is in fluid communication with nozzle 130. Fluid is ejected onto the interior surface 110 of the enclosed media 106 at predetermined locations by activating the fluid ejection actuators 150.

For the purposes of this specification and this invention, the term "enclosed medium" may be any solid or semi-solid object whose shape has a substantially fixed form including an inner or interior surface and an outer or exterior surface. The term "substantially fixed form" means the permanence of the inner surface of an object and not the permanence of the shape of an object. For example, a bag may change shape depending on whether it is open or closed, however, the solid of the inner surface is present whether open or closed. In addition, the substantially fixed form includes at least one opening having a cross-sectional area less than the maximum cross-sectional area available for the form. The enclosed medium may have the shape of a cuboid, cylinder, ellipsoid or sphere, to name but a few simple geometries that may be employed. For example, the sealing medium 106 may be a vial, canister, capsule, box, bag, or tube, to name a few of the available items. In an alternative embodiment, as shown in FIG. 1b, the closing medium 106 may comprise a bottom surface such as a vial or a gelatin capsule. Furthermore, the fluid injector head 100 'may also comprise nozzles that inject fluid onto the inner bottom surface 109 and the inner side surface 110' of the capsule, as shown in fig. 1 b.

In this embodiment, fluid ejector body 120 includes a plurality of holes or nozzles 130, the actual number shown in FIGS. 1a and 1b being shown for illustrative purposes only. The number of nozzles used depends on various parameters such as the particular fluid or fluids to be dispensed, the particular deposit to be produced and the particular size of the confining medium used. In this embodiment, either the fluid ejector body 120 or the enclosure media 106, or both, may be rotated about the longitudinal axis 112 of the enclosure media 106, thereby providing the ability to dispense fluid onto the interior surface of the enclosure media in a two-dimensional array. Fluid ejector head 100 provides control over fluid deposits by dispensing discrete amounts of fluid onto the interior of an enclosed medium in a controlled manner.

It should be noted that the figures are not drawn to true scale. Also, various elements are not drawn to scale. Certain dimensions have been exaggerated relative to other dimensions to provide a clearer description and understanding of the present invention.

Further, while several of the embodiments illustrated herein are shown in two-dimensional views having various regions including depth and width, it should be clearly understood that these regions are merely illustrative of a portion of a device that is actually a three-dimensional structure. Thus, when fabricated on an actual device, these regions have three-dimensional dimensions including length, width, and depth. Moreover, while the invention has been illustrated by various embodiments, it is not intended to limit the scope or applicability of the invention to those illustrated. Furthermore, the various embodiments of the invention are not intended to be limited to the physical configurations shown. These structures are merely illustrative of the utility and application of the present invention in presently preferred embodiments.

In this embodiment, fluid injector body 120 is a tubular structure having an outer diameter that is smaller than an inner diameter of closing medium opening 108 such that fluid injector body 120 is insertable into closing medium opening 108 along longitudinal axis 112 of closing medium 106. In this embodiment, fluid injector body 120 further includes a fluid injector body longitudinal axis 111 that is aligned with longitudinal axis 112 of enclosure medium 106. In alternative embodiments, depending on various parameters such as the shape of the enclosing medium and the fluid injector body, the fluid injector body longitudinal axis may not be aligned with the longitudinal axis of the enclosing medium. Any ceramic, metal, or plastic material capable of being formed into a suitably sized tubular shape may be used for the fluid ejector body 120. Fluid ejection actuator 150 can be any device capable of imparting sufficient energy to fluid in the vicinity of fluid channel 140 or nozzle 130. For example, a compressed air actuator or an electromechanical or thermo-mechanical actuator, such as those used in spray guns, may be employed to eject fluid from nozzle 130.

Figure 2a illustrates an exemplary embodiment of a fluid ejector head in an isometric cross-sectional view. In this embodiment, fluid injector head 200 includes a fluid injector body 220, wherein at least a portion of the body has a rectangular cross-section. In an alternative embodiment, the fluid ejector body may have a parallelepiped structure. In addition, the fluid injector body 220 also includes a fluid body longitudinal axis 211 passing through the cross-sectional view. The fluid ejector body 220 is adapted to be inserted into an opening of a closure medium and rotatable therein. In addition, the nozzle 230 has an ejection axis 231 that defines a general direction in which droplets are ejected from the fluid ejector body 220. The fluid body longitudinal axis 211 and the nozzle spray axis 231 form a predetermined spray angle 218 (see fig. 2 b). In this embodiment, the nozzle spray axis 231 may be at an angle of 0-60 degrees from the fluid body normal 211' to the fluid body longitudinal axis 211, as shown in the perspective view in FIG. 2 b. In an alternative embodiment, nozzle firing axis 232 is at an angle of 0-45 degrees to fluid body longitudinal axis 211, and more preferably nozzle firing axis 232 is substantially perpendicular to fluid body longitudinal axis 211. In addition, the spray angles 231 'and 231 "illustrate that the angles may be in a positive or negative direction relative to the fluid body normal 211'.

Fluid ejector head 200 also includes fluid ejection actuators 250, chamber layer 266, fluid body housing 280, and nozzle layer 236. In this embodiment, the substrate 222 is part of a silicon wafer. In alternative embodiments, other materials may be used for substrate 222, such as various glasses, alumina, polyimide substrates, silicon carbide, and gallium arsenide. Thus, the present invention is not limited to those devices fabricated from silicon semiconductor materials. In this embodiment, the fluid body housing 280 and the substrate 222 form a fluid channel 240. Fluid inlet channel 241 is formed in substrate 222 and provides a fluid connection between fluid channel 240 and fluid ejection chamber 272.

A fluid energy generating element 252 is located on the substrate 222 and provides an energy pulse for ejecting fluid from the nozzle 230. As described above, fluid ejection actuator 250 can be any element capable of imparting sufficient energy to fluid to cause it to be ejected from nozzle 230. In this embodiment, fluid ejection actuator 250 includes a fluid energy generating element 252, which is a thermistor. In alternative embodiments, other fluid energy generating elements such as piezoelectric, flexo-tensile, acoustic, and electrostatic energy generators may be used. For example, a piezoelectric element uses voltage pulses to generate pressure on a fluid, thereby ejecting droplets of the fluid. In other embodiments, the fluid energy generating element 252 may be laterally spaced a distance from the nozzle 230. The particular distance depends on various parameters such as the particular fluid dispensed, the particular configuration of the chamber 272, and the configuration and dimensions of the fluid channel 240, to name a few parameters.

The thermistor is typically formed as a tantalum-aluminum alloy using conventional semiconductor processing equipment. In alternate embodiments, other resistive alloys such as tungsten silicon nitride or polysilicon may be used. The thermistor is typically connected to the electrical input through metallization (not shown) on the surface of the substrate 222. Furthermore, a different protective layer against chemical and mechanical corrosion can be applied to the thermistor, but is not shown in fig. 2 for the sake of clarity. In this embodiment, the substrate 222 also includes active devices, such as one or more transistors (not shown for clarity) electrically connected to the fluid energy generating elements 252. In alternative embodiments, other active devices such as diodes or memory logic cells may be used, either alone or integrated with the one or more transistors. In other embodiments, a fluid ejection head commonly referred to as a "direct drive" head may also be used, wherein substrate 222 may include a fluid ejection generator without active devices. The particular combination of active devices and fluid energy generating elements depends on various parameters such as the particular application in which fluid ejection head 200 is used and the particular fluid being ejected, to name a few parameters.

In this embodiment, an energy pulse applied to the thermistor rapidly heats a component in the fluid to its boiling point, causing the fluid component to vaporize, creating an expanding bubble of ejected fluid droplets 214 as shown in FIG. 2 a. Fluid droplet 214 generally includes a droplet head 215, a droplet tail 216, and a satellite droplet 217, which appears substantially as one fluid droplet. In this embodiment, each actuation of the energy-generating element 252 ejects a precise amount of fluid in the form of a substantially fluid droplet; thus, the number of actuations of the fluid energy generating elements controls the number of droplets 214 ejected from nozzle 230 (i.e., n actuations produce substantially n fluid droplets). As such, fluid ejector head 200 may produce deposits of discrete droplets of fluid, including solid materials dissolved in one or more solvents or suspended or dispersed in a fluid, at discrete predetermined locations on the interior surface of the enclosed substrate.

The drop volume of fluid drop 214 may be optimized by various parameters such as nozzle aperture, nozzle layer thickness, chamber size, chamber layer thickness, energy generating element size, and fluid surface tension, to name a few. In this way, droplet volume can be optimized for the particular fluid being ejected and the particular application in which the confining medium is used. The fluid ejector head 200 described in this embodiment can repeatedly and reliably eject droplets in the range of about 5 femtoliters to about 10 nanoliters, depending on the parameters and configuration of the fluid ejector head described above. In alternative embodiments, fluid ejector head 200 may eject droplets in the range of about 5 femtoliters to about 1 microliter. Moreover, according to other embodiments, multiple fluid injector heads 200 may be grouped together to form a polygonal structure. For example, two fluid ejection heads 200 may be shaped back-to-back to provide the ability to dispense two different fluids, such that one set of fluid ejection heads may dispense ink, while another set of fluid ejection heads may dispense a sealant or protective material to cover or coat the dispensed ink. Yet another example is the use of multiple sets of fluid ejection heads to eject multiple different fluids such as color inks with or without the use of sealants or protective materials. The term "fluid" includes any fluid material such as inks, adhesives, lubricants, chemical or biological agents, and fluids containing dissolved or dispersed solids in one or more solvents. In addition, the fluid ejection head 200 may also contain a fluid that is a mixture of materials, thereby providing multiple functions, thus making various combinations possible, such as having one set of fluid ejection heads eject one ink and protective material mixed together, and having another set eject only one ink.

A chamber layer 266 is selectively applied to the surface of substrate 222. Sidewall 268 defines or forms a fluid ejection chamber 272 around energy generating element 252 such that upon activation of energy generating element 252, fluid flowing from fluid channel 240 through fluid inlet channel 241 is collected in fluid ejection chamber 272 prior to activation of energy generating element 252 and discharge of fluid through nozzle or orifice 230. The nozzle or orifice layer 236 is located on the chamber layer 266 and includes one or more orifices or nozzles 230 that eject fluid. In an alternative embodiment, an adhesive layer (not shown) may also be used to bond nozzle layer 236 to chamber layer 266, depending on the particular materials used for chamber layer 266 and nozzle layer 236. According to other embodiments, chamber layer 266 and nozzle layer 236 are formed as a single unitary chamber nozzle layer. Chamber layer 266 is typically a photosensitive imaging film that utilizes a lithographic apparatus to form chamber layer 266 on substrate 222 and then define and form fluid ejection chambers 272. The nozzles shaped along longitudinal axis 211 may be positioned in a straight or staggered configuration, as shown in fig. 2b, depending on the particular application in which fluid ejection head 200 is utilized.

The nozzle layer 236 may be formed of metal, polymer, glass, or other suitable material, such as ceramic. In this embodiment, the nozzle layer 236 is a polyimide film. Examples of commercially available nozzle layer materials include a polyimide film sold under the trade name "Kapton" by e.i. dupont de Nemours & co, a polyimide material sold under the trade name "Upilex" by Ube Industries, LTD of japan. In an alternative embodiment, nozzle layer 236 is formed of a metal, such as a nickel substrate enclosed by a thin gold, palladium, tantalum or rhodium layer. In other alternative embodiments, the nozzle layer 236 may be formed from a polymer such as polyester, polyethylene terephthalate (PEN), epoxy, or polycarbonate.

Figure 3 illustrates a cross-sectional view of an alternative embodiment of a fluid ejector head. In this embodiment, fluid injector head 300 includes a fluid injector body 320, wherein at least a portion of the body has a cross-sectional shape of a cylinder, including a fluid body longitudinal axis 311 through the cross-sectional view. In alternative embodiments, the fluid ejector body 320 may have a curvilinear shaped portion. The fluid injector head 300 also includes a fluid injection activator 350, a second fluid injection activator 354, and a third fluid injection activator 358 on the fluid injector body 320. Although these fluid ejection actuators are located below the nozzles in this embodiment, in alternative embodiments they may be located laterally spaced from the nozzles. The particular distance depends on various parameters such as the particular fluid dispensed, the particular configuration of the chamber, and the configuration and dimensions of the fluid channel, to name a few. Fluid channel spacer 346 is attached to substrate 322 and divides fluid injector head 300 into three sections: a fluid section 323, a second fluid section 324, and a third fluid section 325. In this embodiment, fluid channel 340 is formed by fluid channel partition portion 346' and substrate 322; second fluid channel 342 is formed by fluid channel partition portion 346 "and substrate 322; the third fluid passage 344 is formed by a fluid passage baffle portion 346' "and the substrate 322.

Fluid inlet passage 341 provides a fluid connection between fluid channel 340 and chamber 372 and is formed in substrate 322 within fluid section 323. Fluid inlet passages 343 and 345 provide fluid connections between fluid passages 342, 344 and chambers 374, 376, respectively. A fluid energy generating element 352 is located on substrate 322 and provides energy pulses for ejecting fluid from nozzle 330. Fluid energy generating elements 356 and 360 provide energy pulses for ejecting fluid from nozzles 332 and 334, respectively. In this embodiment, fluid energy generating elements 352, 356, and 360 are thermistors that rapidly heat a component of a fluid above its boiling point, causing the fluid component to vaporize, thereby ejecting droplets of the fluid. In alternative embodiments, other fluid energy generating elements such as piezoelectric, flexo-tensile, acoustic, and electrostatic energy generators may be used. In this embodiment, fluid energy generating elements 352, 356, and 360 eject fluid substantially radially onto the inner surface of an enclosed medium (not shown).

Chamber layer 366 is situated over substrate 322 with sidewalls 368' defining or forming a portion of fluid ejection chamber 372 in fluid section 323; sidewall 368 "forms a portion of second fluid ejection chamber 374 in second fluid section 324; and sidewall 368' form a portion of fluid ejection chamber 376 in third fluid section 325. Nozzle or orifice layer 336 is located on chamber layer 366 and includes one or more apertures or nozzles 330, 332, and 334 through which fluid may be ejected in three sections. In an alternative embodiment, an adhesive layer may also be used to adhere nozzle layer 336 to chamber layer 366, depending on the particular materials used for chamber layer 366 and nozzle layer 336. According to other embodiments, the chamber layer 366 and the nozzle layer 336 may be formed as a single layer. Such an integrated chamber and nozzle layer structure is commonly referred to as a chamber orifice layer or chamber nozzle layer.

Although fig. 3 illustrates a fluid injector body 320 divided into three sections, alternative embodiments may utilize a single section anywhere from a plurality of sections depending on the particular application in which fluid injector head 300 is utilized. For example, the fluid ejector body 320 may have a single section to eject a single fluid. Additionally, fluid chambers formed along longitudinal axis 311 may be positioned in a straight line, in a staggered configuration, or in a spiral configuration depending on the particular application in which fluid ejection head 300 is utilized. In other examples, the fluid ejector body 320 includes 6 segments having an upright, staggered, or helical configuration, thereby providing any feasible combination of dispensing multiple fluids.

In addition to having multiple sectors, each sector can be independently optimized for performance. For example, the energy generating elements of each segment may be optimized with respect to the particular fluid ejected by that segment. In addition, the dimensions of the ejection chamber and nozzle may also be optimized with respect to the particular fluid ejected by the segment. Moreover, the size of the energy-generating elements, chambers, and nozzles within a segment may also be varied to cause different droplet sizes of the same fluid to be ejected from fluid ejection head 300.

Referring to fig. 4, an alternate embodiment of the fluid ejector head of the present invention is shown in cross-section. In this embodiment, the fluid injector head 400 includes a fluid injector body 420 having a rectangular or square tubular cross-sectional shape including a longitudinal axis 412 passing through the cross-sectional view. The fluid injector head 400 also includes a fluid injection actuator 450, a second fluid injection actuator 454, a third fluid injection actuator 458, and a fourth fluid injection actuator 460 located on the fluid injector body 420. Fluid channel spacer 446 is attached to substrate 422 and divides fluid injector head 400 into four sections: first fluid segment 440, second fluid segment 424, third fluid segment 425, and fourth fluid segment 426. For example, four different fluids may be used, such as black ink and three color inks. In other examples, four different reactants may be employed. In other examples, various combinations of different fluids may be utilized, such as two different bioactive agents, an absorbable ink, and a protective material covering the bioactive agent or the ink, or both. In this embodiment, fluid channel 440 is formed by fluid channel partition portion 446' and substrate 422; second fluid channel 442 is formed by fluid channel partition portion 446 "and substrate 422; the third fluid passage 444 is formed by a fluid passage partition portion 446' and the substrate 422; and a fourth fluid channel 448 is formed by the fluid channel partition portion 446 "" and the substrate 422.

Fluid inlet channel 441 provides fluid connection between fluid channel 440 and fluid ejection chamber 472 and is formed in substrate 422 within fluid section 423; fluid inlet channel 443 provides a fluid connection between fluid channel 442 and fluid ejection chamber 474; fluid inlet passage 445 provides a fluid connection between fluid passage 444 and fluid ejection chamber 476; and fluid inlet passage 449 provides a fluid connection between fluid passage 448 and fluid ejection chamber 473. Fluid energy generating elements 452, 456, 459, and 463 are located on substrate 422 and provide energy pulses for ejecting fluid from nozzles 430, 432, 434, and 436, respectively. As with the previous embodiments, fluid energy generating elements 452, 456, 459, and 463 can be any element capable of imparting sufficient energy to a fluid to cause it to be ejected from a nozzle.

The chamber orifice layer 478 is positioned on the substrate 422 with the sidewalls 468 defining or forming a portion of the fluid ejection chamber 472; side wall 469 forms a portion of fluid ejection chamber 474; side wall 470 forms a portion of fluid ejection chamber 473; sidewall 471 forms a portion of fluid ejection chamber 476. The chamber orifice layer 478 also includes one or more orifices or nozzles 430, 432, 434, and 436, respectively, in each section through which fluid is ejected.

Although fig. 4 illustrates the fluid injector body 420 divided into four sections, alternative embodiments may employ even more sections depending on the particular application in which the fluid injector head 400 is utilized. For example, the fluid injector body 420 may have 5 or 6 sections or other numbers of sections, respectively, forming a pentagonal or hexagonal or polygonal shape, depending on the particular application in which the fluid injector head 400 is used, providing any of a variety of possible combinations for distributing a plurality of fluids. As described above, fluid chambers and nozzles formed along longitudinal axis 412 may be positioned in a straight line or in a staggered configuration depending on the particular application in which fluid ejection head 400 is used. Furthermore, as also described above, optimization of performance can also be achieved independently for each segment as well as for the chamber, the nozzle, and the energy generating element.

Referring to fig. 5, an alternate embodiment of the fluid ejector head of the present invention is shown in cross-section. In this embodiment, fluid injector head 500 includes a fluid injector body 520 having a rectangular shape including a fluid body longitudinal axis 511 in cross-section. In addition, fluid ejection head 500 includes a combination of different types of fluid ejection actuators. First and second fluid ejection actuators 550 and 551 are of a first type and third and fourth fluid ejection actuators 554 and 558 are of a second type. In this embodiment, first and second fluid-ejection actuators 550 and 551 are piezoelectric transducers 552 and 553, and third and fourth fluid-ejection actuators 554 and 558 are thermistor energy-generating elements 556 and 560, respectively.

Fluid section 523 includes a membrane 562 coupled to substrate 522 and piezoelectric transducer 552, and fluid section 526 includes a membrane 563 coupled to substrate 523 and piezoelectric transducer 553. A voltage pulse applied to piezoelectric transducer 552 or 553 produces a physical displacement of the piezoelectric transducer and diaphragm, thereby producing a pressure on the fluid located in fluid ejection chamber 570 or 572 to eject a fluid droplet from nozzle 530 or 536. Chamber orifice layer 578 is positioned on substrates 522 and 523 with sidewalls 568 and 569 defining or forming a portion of fluid ejection chambers 570 and 572, respectively. The chamber orifice layer 578 also includes one or more orifices or nozzles 530 and 536 through which the fluid is ejected. Fluid inlet channels 541 and 543 provide fluid connections between fluid channels 540, 542 and fluid ejection chambers 570, 572 and are formed between substrate 522 and chamber orifice layer 578 in fluid sections 523 and 526.

The third and fourth fluid sections 524, 525 are formed by the substrate 521 and the channel ceiling 538 of the fluid ejector body 520. In addition, substrate 521 and channel ceiling 538 form nozzles 532 and 534. In contrast to the "top injector" configuration shown in FIG. 2, these two sections form what is commonly referred to as a "side injector". In an alternative embodiment, substrate 521 and substrate 523 may be combined to form a single substrate having different energy generating elements located on different portions. In addition, substrate 522 and channel ceiling 538 can be combined. Third fluid inlet passage 545 provides a fluid connection between third fluid passage 544 and third fluid ejection chamber 574. The fourth fluid inlet channel 547 provides a fluid connection between the fourth fluid channel 546 and the fourth fluid ejection chamber 576. Fluid energy generating elements 556 and 560 are located on substrate 521 and provide energy pulses for ejecting fluid from nozzles 532 and 536, respectively.

Although the embodiment shown in FIG. 5 shows fluid segments 523 and 526 with piezoelectric transducers having fluid segments 524 and 525 with thermistors for ejecting fluid, alternative embodiments may utilize any combination of energy generating elements described in the above embodiments. Combining a thermistor "top ejector" and a side ejector in the same fluid ejector head, or a piezoelectric transducer and an ultrasonic transducer in the same fluid ejector head, are just a few examples of different energy producing element combinations that may be utilized. In another example, fluid ejector head 500 may include one section that utilizes a compressed air fluid ejection actuator, a second section that utilizes a piezoelectric fluid energy generating element, and third and fourth sections that utilize a thermistor energy generating element.

Referring to fig. 6a, an exemplary embodiment of a fluid ejection cartridge 602 of the present invention is shown in a perspective view. In this embodiment, the fluid ejection cartridge 602 includes a fluid ejection head 600 fluidly connected to the fluid reservoir 628. The fluid ejector body 620 is adapted to be inserted into a closed media opening (not shown). Fluid injector head 600 also includes a nozzle 630 located on fluid injector body 620 and fluidly connected to fluid channel 640. The fluid contained in the fluid container 628 is supplied to the fluid passage 640 through the filter 648. In addition, the fluid ejection actuator 650 is in fluid communication with the nozzle 630 such that when the fluid ejection actuator is actuated, fluid is ejected from the nozzle 630. In this embodiment, fluid ejection actuator 650 is electrically coupled to electrical connectors 668 through electrical traces or wires (not shown). In alternative embodiments, for example using compressed air, connecting the fluid ejection actuator 650 to the fluid controller (see fig. 6b), different connectors such as compressed air fittings and tubing may be utilized. Fluid injector head 600 may be any of the fluid injector heads described in the embodiments above.

The information storage element 664 is located on the fluid ejection cartridge 602 as shown in fig. 6 a. The information storage element 664 is electrically connected to electrical connector 668. In an alternative embodiment, information storage element 664 may utilize a separate electrical connector located on body 660. The information storage element 664 may be any type of storage device suitable for storing and outputting information to a controller, which may be related to the performance or parameters of the fluid or the fluid injector head 600, or both. In this embodiment, information storage element 664 is a storage chip that is mounted on body 660 and electrically connected to electrical connectors 668 through electrical traces 670. When the fluid ejection cartridge 602 is inserted or utilized in a fluid dispensing system, the information storage element 664 is electrically connected to a controller (not shown) that communicates with the information storage element 664 to utilize the information or parameters stored therein.

Referring to fig. 6b, an exemplary embodiment of a fluid dispensing system 604 of the present invention is shown in a perspective view. In this embodiment, the fluid dispensing system 604 includes an enclosed media tray 684 having an n x m array of enclosed media retainers 686 adapted to allow insertion of enclosed media portions 606. The fluid distribution system 604 also includes an i x j array of fluid ejection cartridges 602 that includes a fluid ejector body 620 adapted to be inserted into the enclosed media opening 608. For example, one system may employ a tray having a 4 x 4 array of holders containing enclosed media portions and a 2 x 2 array of fluid ejector bodies, wherein the tray may be effectively divided into four 2 x 2 holder sections, and the fluid ejector bodies are inserted into the enclosed media portions in each section. In this embodiment, the array of fluid ejection cartridges 602 is mounted on a distribution bracket 688. A fluid ejection actuator 650 (see fig. 6a) is operatively connected to the fluid ejector body 620 and the fluid controller 690 such that the fluid controller 690 actuates the fluid ejection actuator (see fig. 6a) to eject fluid onto the interior surface of the enclosed media portion 606. In addition, the fluid controller 690 may be operatively coupled to a rotation mechanism (not shown) on the fluid ejection cartridge 602 to rotate the fluid ejector body 620 about the fluid body longitudinal axis (not shown).

The transport mechanism 692 is coupled to either the dispensing bracket 688 or the enclosed media tray 684 or both, depending on the particular application in which the dispensing system 604 is used. The transport mechanism 692 is operably connected to the transport controller 694 and provides signals that control the movement of the enclosed media tray 684 to align the enclosed media opening 608 with the fluid ejector body 620 and insert and remove the fluid ejector body 620 from the enclosed media portion 606. For example, the transport mechanism 692 may move the enclosed media tray 684 in the X and Y lateral directions while raising and lowering the dispensing bracket 688 (i.e., movement in the Z direction) to insert and remove the fluid ejector body 620 from the enclosed media portion 606, as shown in fig. 6 b. In alternative embodiments, other combinations of motions may be utilized and controlled by the transport mechanism 692, such as rotation of the enclosed media tray 684 about a central axis to provide additional aligning motion. In this embodiment, the fluid controller 690 and the transfer controller 694 may utilize any combination of Application Specific Integrated Circuits (ASICs), microprocessors, and programmable logic controllers to control the various functions of the fluid distribution system 604. The particular device will be used depending on the particular application in which the fluid dispensing system 604 is used. In addition, the dispensing system 604 may optionally include an enclosed media loader 698 to load the enclosed media portions 606 into the enclosed media retainers 686. Moreover, the distribution system 604 may also include a closing medium rotor 685 to rotate the closing medium portion 606 about the closing medium longitudinal axis (see FIGS. 1a and 1b), thereby rotating the inner surface of the closing medium about the fluid injector body. Rotation of the enclosed media portion 606 or rotation of the fluid ejector body 620 or both may be used to create a two-dimensional array of discrete deposits that are dispensed onto the interior surface of the enclosed media portion 606.

An optional inspection unit 696 may be utilized to provide on-line, non-destructive quality assurance testing of the article of manufacture. The particular functions performed by the inspection unit 696 depend on the particular application in which the dispensing system 604 is used. For example, the inspection unit 696 may be used to monitor the amount of material deposited when dispensing a bioactive agent onto the inner surface of a gelatin capsule. Another example is monitoring the reaction products as various reactants are dispensed onto the interior surface of a vial or other suitable container. For example, near infrared or other optical techniques can be used to rapidly perform on-line testing of one or more bioactive agents on the enclosed media portion 606. In addition, inspection unit 696 may also be employed to optically monitor the quality of characters produced on the interior surface of a jar, vial, or other suitable container.

Referring to fig. 7, a flow chart of a method of manufacturing a fluid injector head in an embodiment of the present invention is shown. Substrate forming process 780 includes fabricating a substrate suitable for insertion into the enclosed dielectric opening. The substrate may be made of any suitable ceramic, metal or plastic material that can be formed to fit the opening of the elongate seal. The particular material used for the substrate will depend on the particular application in which the fluid ejector head will be used. For example, if active devices are desired, substrates having thermal, chemical and mechanical properties suitable for semiconductor processing, such as various glasses, alumina, polyimide substrates, silicon carbide, and gallium arsenide, to name a few, may be used. However, if "direct drive" is desired, less thermally, chemically and mechanically demanding substrates, such as various plastic materials, may be used. The substrate forming process 780 includes forming the substrate in a desired shape, such as a cylindrical, rectangular, or other polygonal configuration, depending on the particular application for which the fluid ejector head is used.

Optional active device formation process 782 utilizes conventional semiconductor processing equipment to form the transistors and other logic devices required for operation of the fluid ejector head on the substrate. These transistors and other logic devices are typically formed as a stack of thin film layers on a substrate. However, the particular structure of the transistor is not relevant to the present invention and different types of solid state electronic devices may be employed, such as metal oxide field effect transistors (MOSFETs) or Bipolar Junction Transistors (BJTs). As noted above, other substrate materials may also be used. Thus, the substrate material may also comprise any available semiconductor material and technology, such as Thin Film Transistor (TFT) technology using polysilicon on a glass substrate.

Fluid energy generating element forming process 784 relies on the particular transducer used in the fluid ejection head to form the fluid ejection actuators. Generally, in the case of thermistor elements, the resistors are formed as tantalum-aluminum alloys using conventional semiconductor processing equipment such as a sputtering deposition system for forming the resistors and an etching lithography system for defining the position and shape of the resistor layer. In alternative embodiments, resistive alloys such as tungsten silicon nitride or polysilicon may also be used. In alternative embodiments, a fluid droplet generator other than a thermistor may be used, such as a piezoelectric or ultrasonic generator. In other embodiments, such as those utilizing compressed air, the fluid ejection actuators may be formed by forming one or more diaphragms in the fluid in communication with the nozzle. Furthermore, in those embodiments that utilize active devices formed on a substrate, some active devices are typically electrically connected to the fluid energy generating elements through electrical traces made from an aluminum alloy such as aluminum copper silicon, which is commonly used in integrated circuit technology. Other interconnect alloys such as gold or copper may also be used.

The chamber layer forming process 786 forms a chamber layer, or a chamber orifice layer formed when an integrated chamber layer and nozzle layer are employed, depending on the particular material selected. The particular material selected depends on a number of parameters such as the spray fluid, the expected lifetime of the fluid ejection head, the dimensions of the fluid ejection chamber and the fluid feed channel therein. Typically, conventional photoresist and lithographic processing equipment or conventional circuit board processing equipment is employed. For example, the processes used to form the photoimageable polyimide chamber layer are spin coating and soft baking. However, forming chamber layers, commonly referred to as solder masks, typically employs a coating process or a lamination process to adhere the material to the substrate. Other materials such as silicon oxide or silicon nitride may also be used as chamber layers by using deposition tools such as plasma enhanced chemical vapor deposition or sputtering.

The sidewall definition process 788 is typically patterned using a photolithographic tool. For example, after a photoimageable polyimide or solder mask has been formed on the substrate, the chamber layer will be exposed through a mask having the desired chamber characteristics. The chamber layer is then processed through a development step and a final baking step, typically following development. Other embodiments may also employ a technique similar to that commonly referred to as lost wax casting. In this procedure, the fluid chambers and fluid channel structures and orifices or holes are typically formed using lost wax or lost material that may be removed, for example, by solubility, corrosion, heat, photochemical reaction, or other suitable means. Generally, polymeric materials are coated onto these structures formed by lost wax materials. The lost wax material is removed by one or a combination of the above methods, leaving a fluid cavity, fluid channel, and orifice formed in the coating material.

Nozzle or orifice forming process 790 forms a nozzle layer according to the particular material selected. The particular material selected will depend on a number of parameters such as the fluid ejected, the expected printhead life, the size of the orifice, the orifice shape, and the orifice wall structure therein. Generally, laser ablation may be employed. However, other techniques such as perforation, chemical etching or micro-molding may also be used. The method used to apply the nozzle layer to the chamber layer also depends on the particular materials selected for use in the nozzle layer and the chamber layer. Typically, the nozzle layer is attached or secured to the chamber layer by sandwiching an adhesive layer between the chamber layer and the nozzle layer, or laminating the nozzle layer to the chamber layer with or without an adhesive layer.

As described above (see fig. 4-5), some embodiments may employ an integrated chamber and nozzle layer structure, referred to as a chamber orifice or chamber nozzle layer. The layer typically uses some combination of the above methods depending on the particular material selected for the integral layer. For example, in one embodiment, the thin films typically used in nozzle layers may be formed with nozzles and fluid ejection chambers within the layers by such techniques as laser ablation or chemical etching. However, the layer may be secured to the substrate by using an adhesive. In an alternative embodiment, a photoimageable epoxy may be provided on the substrate, followed by the formation of the chamber layer and nozzles using conventional photolithographic techniques, such as multiple exposures before a development cycle. In other embodiments, a lost wax casting process may also be used to form the integrated chamber and nozzle layer structure, as described above.

The fluid inlet channel forming process 792 is dependent upon the particular material used for the substrate. For example, to form fluid inlet channels in a silicon substrate, dry etching may be used when vertical or orthogonal sidewalls are desired. However, where a sloped sidewall is desired, a wet etch process such as tetramethylammonium hydroxide (TMAH) may be used. Furthermore, when a more complex structure is used to form the fluid inlet channel, a combination of wet etching and dry etching may also be used. Other methods such as laser ablation, reactive ion etching, ion milling including focused ion beam patterning, etc. may also be used to form the fluid inlet passageway depending on the particular substrate material used. Micro-molding, electroforming, punching or chemical etching are also examples of techniques that may be employed depending on the particular substrate material used.

Fluid channel forming process 794 generally employs an injection molding process to form fluid channels of a specified shape depending on the particular application in which the fluid ejection head is used. The injection molded fluidic channel is then bonded to the substrate or fluidic body housing using a suitable adhesive, depending on the particular structure employed.

Optional fluid body housing forming process 796 generally employs an injection molding process to form a fluid body housing of a prescribed shape depending on the particular application in which the fluid ejection head is used. In some embodiments, as shown in fig. 2a and 2b, the fluidic body housing forming process 796 and the fluidic channel forming process 794 may be combined into a single process to form the fluidic body housing and the fluidic channel. For example, as shown in FIG. 2a, the fluid body housing and substrate are attached together using a suitable adhesive such that the fluid ejector body is adapted to be inserted into the opening of the enclosure media. In other embodiments, the fluid ejector body is created by a nozzle layer formed on a chamber layer on a substrate as shown in FIG. 3.

FIG. 8 illustrates a flow diagram of an exemplary embodiment of a method for dispensing a discontinuous deposit of material onto an interior surface of an enclosed medium using a fluid dispensing system. The align close media process 810 is used to align the opening of the close media with the fluid ejector head so that the fluid ejector body can be inserted into the close media. The enclosed media is typically located in an enclosed media tray or other holding device. The tray or other holding device is controlled by the transport mechanism and transport controller. Any conventional technique for aligning components may be used. For example, an electric or pneumatic motor or other actuator may move the tray or other holding device in the X and Y directions to achieve proper alignment of the enclosed media with the fluid ejector head. In addition, a rotation alignment of the greek letter θ or about the Z axis is also generally possible. Also, sensors or optical vision systems or combinations thereof located on the holding device are typically utilized to provide feedback that the sealing medium is properly aligned with the fluid ejector body. In alternative embodiments, the transfer controller may be associated with a fluid ejection cartridge or head mounted on the dispensing carriage to move the fluid ejector body or both the fluid ejector body and the retaining device to properly align the enclosed media with the fluid ejector head.

The fluid ejector body is inserted into the opening of the closing medium using an insert fluid ejector body procedure 820. The fluid ejection head is typically controlled by a fluid ejection cartridge or fluid ejection head position controller or transport mechanism and transport controller. For example, in one embodiment, an electric or pneumatic motor may raise and lower the fluid ejector head in the Z-direction to provide movement to insert the fluid ejector body into the enclosed media opening. In alternative embodiments, a tray or other holding device or combination of a tray and a fluid ejector head is moved to insert the fluid ejector head into the opening of the enclosure media.

The actuating fluid ejection actuator procedure 830 is utilized to eject fluid from at least one nozzle located on a fluid ejector body. In general, a droplet ejection controller or fluid controller located in a fluid distribution system in connection with a fluid ejector head energizes a fluid ejection actuator to eject droplets of a fluid. For those embodiments that utilize a fluid energy generating element, such as a piezoelectric or thermistor element, a droplet ejection controller typically actuates multiple fluid energy generating elements to eject a fluid droplet substantially each time the fluid energy generating element is actuated. In general, the fluid energy generating element can repeatedly and reliably eject droplets in the range of about 5 femtoliters to about 10 nanoliters. Such droplet sizes are consistent with deposition in the picogram to microgram range depending on the desired amount of deposition material in proportion to the amount of solvent in the ejected fluid droplets. However, depending on the particular application in which the fluid dispensing system is used, the size of these fluid droplets can be controlled in the range of about 5 femtoliters to about 1 microliter. Such droplet sizes are consistent with deposition in the picogram to microgram range depending on the desired amount of deposition material in proportion to the amount of solvent in the ejected fluid droplets.

The dispense fluid process 840 is utilized to dispense fluid and control the position of the ejected fluid droplets on the interior surface of the enclosed medium to form discrete media deposits. Depending on the particular fluid ejector head used, droplets of fluid may be ejected from the nozzle along a nozzle ejection axis at a predetermined ejection angle from the normal to the body of fluid. In one embodiment, the nozzle axis of injection is at an angle of about 0-60 degrees from the normal to the fluid body. In an alternative embodiment, the nozzle ejection axis of the fluid ejector head may be at an angle of about 0-45 degrees from the normal to the fluid body. Preferably, the nozzle ejection axis of the fluid ejector head is substantially perpendicular to the fluid ejector body longitudinal axis.

Additionally, the dispense fluid sequence 840 may also include an optional rotational displacement sequence depending on the particular fluid ejector body used. For example, for those embodiments that utilize fluid ejector heads that eject a particular fluid through a single row of nozzles, the rotational angular displacement process is used to form multiple rows of discrete deposits. By using rotation, the dispense fluid process 840 can create a two-dimensional array, thereby forming an areal density of fluid deposits on the interior surface of the enclosed medium. Three-dimensional arrays may also be created by dispensing fluid deposits on top of previously dispensed fluid deposits. In addition, for those embodiments utilizing fluid ejector heads having multiple rows of nozzles, rotational angular displacement may be used to form multiple rows of discrete deposits with smaller spacing between deposits than would be obtained with the same fluid ejector head without rotation. The angular rotational displacement may be achieved by any conventional technique for performing rotational movement, such as by means of an electric or pneumatic motor or a piezoelectric motor, to name a few examples. The rotational displacement may be imparted to the closing medium, the fluid ejector body, or some combination thereof.

The dispense fluid process 840 may also include an optional vertical displacement process. The vertical displacement process may be used to create multiple rows of discrete deposits with a smaller pitch between deposits than is typically achieved with the same fluid injector head that is not vertically displaced. The fluid droplet controller typically controls the vertical displacement, although a separate controller may be used. For example, the fluid droplet controller may be coupled to a tray position controller or a fluid ejector head controller or both to produce the appropriate vertical displacement. In alternative embodiments, a separate controller, motor, or other actuator may be employed to generate the appropriate vertical displacement. By employing various combinations of rotational angular displacement and vertical displacement, different structures can be produced, for example from a layer formed by a simple two-dimensional array or overlapping deposits to more complex structures such as a three-dimensional array.

Referring to fig. 9a, an article of manufacture using the fluid dispensing system of an embodiment of the present invention is shown in perspective view. In this embodiment, the enclosed medium 906 is a container 930 having an interior surface 910 upon which are printed various alphanumeric characters 950 representing information that is visible to the naked eye and a bar code 940 representing information that is machine-readable. Although the information depicted in FIG. 9a is an alternative embodiment commonly referred to as a "consumer coupon," it may include any desired consumer or manufacturing information. Further, the information may be any symbol, icon, image or text or combination thereof, such as a company logo or cartoon character. Other examples of different forms of information that exist are one-dimensional barcodes, textual information, codes or holograms.

Referring to fig. 9b, a more variably shaped article that may also be produced using the fluid distribution system of an embodiment of the present invention is shown in perspective view. In this embodiment, the closure media 906 is a flexible package 932 having an inner surface 910 with various alphanumeric characters 952 printed upside down for external identification. The alphanumeric characters 952 are produced using ink deposits or dots (not shown) that are deposited in a pattern on the inner surface 910 of the flexible package 932 using a dot matrix operation or other means. As described above in fig. 9a, an image, alphanumeric characters, or a machine-readable code such as a one-dimensional or two-dimensional bar code may be employed.

Referring to fig. 9c, a label manufactured on a gelatin capsule using the fluid dispensing system of one embodiment of the present invention is shown in perspective view. In this embodiment, the enclosed media 906 is a gelatin capsule 934 having an inner surface 910 with a graphic 954 printed thereon that is generated using a dot matrix operation or other means to create an image, alphanumeric characters, or machine-readable code. In this embodiment, the graphic 954 utilizes discrete ink deposits (not shown) to produce an alphanumeric character "agh 3" that is printed in inverted letters on the inside of the enclosed media 906 for recognition from the outside. With conventional packages that print on an exterior surface or on a label that is later applied to the exterior surface of the package, such characters or images are not easily wiped or washed away by printing on the interior of the closure media 906.

Claims (19)

1. A fluid injector head (100, 100', 200, 300, 400, 500, 600) comprising:

a fluid injector body (120, 220, 320, 420, 520, 620) adapted for insertion into an opening (108, 108 ', 608) of a closing medium (106, 106', 906), the closing medium having an inner surface (110, 910);

at least one nozzle (130, 230, 330, 430, 530, 630) disposed on the fluid ejector body;

a fluid ejection actuator (150, 250, 350, 450, 550, 650) in fluid communication with the at least one nozzle, wherein actuation of the fluid ejection actuator causes ejection of fluid through the at least one nozzle to a predetermined location on the interior surface of the enclosed medium.

2. The fluid ejection head of claim 1, wherein the fluid ejection actuator further comprises a fluid energy-generating element (252, 352, 356, 360, 452, 456, 459, 463), wherein actuation of the fluid energy-generating element causes substantial ejection of a droplet (214) of the fluid onto the interior surface of the enclosed media, and the droplet has a substantial fluid volume in a range from about 5 femtoliters to about 10 nanoliters.

3. A fluid ejector head according to claim 2, wherein the enclosure medium further comprises an interior side (110') and an interior bottom surface (109), the fluid substantially said droplets being ejected onto said interior side of the enclosure medium.

4. The fluid ejector head of claim 2, further comprising at least one active device on the fluid ejector body electrically connected to the fluid energy generating element.

5. The fluid ejector head of claim 1, further comprising a second fluid ejection actuator, wherein the fluid ejection actuator is of a first type (550, 551) and the second fluid ejection actuator is of a second type (554, 558).

6. A fluid ejection cartridge, comprising:

a fluid ejector head as in claim 1; and

a fluid reservoir (628) containing the fluid and fluidly connected to the fluid injector head.

7. A fluid dispensing system, comprising:

at least one fluid ejection cartridge as in claim 6;

a fluid controller (690) operably connected to said fluid ejection actuator; and

at least one enclosed media retainer (686) adapted to retain the enclosed media, wherein the fluid controller actuates the fluid ejection actuator to cause fluid to be ejected onto the interior surface of the enclosed media.

8. The fluid dispensing system of claim 7, wherein the at least one fluid ejection cartridge further comprises an i x j array of fluid ejection cartridges, the at least one enclosed media holder further comprising an enclosed media tray (684) having an n x m array of enclosed media holders.

9. The fluid dispensing system of claim 7 wherein said enclosing medium retainer and said fluid controller dispense said fluid onto said interior surface of said enclosing medium in a two-dimensional array.

10. A method of manufacturing a fluid injector head, the method comprising:

forming a fluid ejector body adapted for insertion into a closed media opening, said media having an inner surface;

forming at least one injection orifice (790) on the fluid injector body; and

forming a fluid ejection actuator in fluid communication with said at least one orifice, wherein actuation of said fluid ejection actuator causes ejection of fluid to discrete locations on said interior surface of said elongated enclosed medium.

11. The method of claim 10, wherein forming a fluid ejector body further comprises forming a substrate (780) having at least one active device (782) electrically connected to the fluid ejection actuator.

12. The method of claim 10, wherein forming a fluid ejection actuator further comprises forming at least one fluid energy generating element (784).

13. The method of claim 12, wherein forming at least one fluid energy generating element further comprises forming at least one first type of fluid energy generating element and at least one second type of fluid energy generating element.

14. A method of using a fluid dispensing system, the method comprising:

inserting a fluid ejector body (820) into an opening of a closing medium; and

energizing a fluid ejection actuator (830) to eject fluid;

dispensing the fluid (840) to a predetermined location on at least a portion of the enclosing medium inner surface.

15. The method of claim 14, wherein actuating a fluid ejection actuator further comprises actuating an energy generating element to substantially eject droplets of the fluid, wherein dispensing the fluid further comprises dispensing the fluid onto the interior surface of the enclosed medium in a two-dimensional array of discrete deposits, the substantially droplets having a volume in a range of about 5 femtoliters to about 1 microliter.

16. The method of claim 14, further comprising aligning the closing medium with the fluid ejector body.

17. The method of claim 14, further comprising rotating the closing medium about the fluid ejector body.

18. The method of claim 14, further comprising rotating the fluid ejector body about the closing medium.

19. The method of claim 14, wherein the fluid comprises a solid component, and wherein dispensing the fluid further comprises dispensing the fluid as discrete deposits, wherein the solid component weighs between about 1 picogram and about 1 microgram.