JP2007118343A - Liquid jet head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To markedly simplify working processes in manufacturing a liquid jet head by allowing a worker to visually specify a distance from an ejection hole face (a nozzle face) to a heater. <P>SOLUTION: A plurality of holes 108 having different depths are provided to an edge section of an ejection nozzle array 106, and each of the shapes of the holes is varied in a stepwise fashion depending on the depth so that a worker specifies an amount of the ground surface by visually observing the shape of the hole after the grinding. That is, the distance from the ejection hole face 105 to the heater 103 is visually specifies. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid discharge head provided in an ink jet recording apparatus.

  Ink jet recording apparatuses form ink discharge droplets by various methods and attach them to a recording member such as recording paper for recording. In particular, inkjet printers that use heat as energy for forming discharged droplets are prepared with a plurality of discharge ports arranged at a high density, and high density and high quality images can be obtained by increasing the density. Can be obtained at a high speed and can be easily colored.

    In recent years, there has been a demand for higher image quality and higher speed, particularly in industrial inkjet recording apparatuses, and in order to achieve these in liquid discharge heads, higher-precision discharge nozzle dimensions are required. Among them, the slight difference in the distance from the discharge port surface (nozzle surface) to the heater was a factor that greatly affected the characteristics of the liquid discharge head, such as the start, ink refill performance, and ink discharge amount. .

Therefore, as a method of confirming the dimensional variation after dicing of the discharge port surface, one is perpendicular to the nozzle surface on the vertical side surface of the nozzle surface to be polished, and the other is a tilted line. Proposals have been made to determine the distance from the discharge port surface to the heater by precisely measuring the distance between these two lines in contact with the nozzle surface during dicing.
(For example, Patent Document 1)

JP2002-240288

  However, the distance from the discharge port surface (nozzle surface) to the heater is about 100 [μm] or less, and the variation is as small as about 20 [μm]. Precise measurement is a serious problem in terms of workability, and there is also a risk of reading errors.

    According to the present invention, a plurality of holes having different depths are provided at the end of the discharge nozzle row, and when each hole shape is changed stepwise depending on the depth, the shape of the hole remaining after polishing is observed to perform surface polishing. Can be identified.

  That is, the distance from the discharge port surface (nozzle surface) to the heater can be visually identified.

  Moreover, it becomes easy to perform correction processing for the target dimension of the distance from the discharge port surface to the heater. Further, since the peripheral portions of the plurality of holes are made of the same material (photosensitive epoxy resin), it is possible to prevent breakage of the peripheral portions of the holes when performing the correction processing. Become.

According to the above invention, since the distance from the discharge port surface (nozzle surface) to the heater can be visually identified, the work process at the time of manufacturing the liquid discharge head can be greatly simplified.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional top view of a liquid discharge head 101 according to the present invention. In FIG. 1, each of the discharge nozzles 106 communicated with the discharge port 104 has a heater 103 for heating the liquid, and the liquid is discharged from the discharge port 104 by heating and foaming the liquid with the heater 103.

  The plurality of discharge nozzles 106 communicate with a common liquid chamber 109, and the common liquid chamber 109 is formed by a liquid chamber frame 110.

  In addition, a plurality of types of holes 108 (hereinafter referred to as EH (Edge-Heather) distance determination holes) for indicating the distance from the discharge port surface 105 to the heater 103 are described at the row end portions of the arranged discharge nozzles 104. ) Is provided.

  Next, description will be made with reference to FIG. 2 in which the periphery of the EH distance determination hole 108 (part A in FIG. 1) is enlarged. Each of the plurality of EH distance determination holes 108 is formed in a stepped shape in cross section, and all have different depths from the discharge port surface 105 and are deepened at equal intervals.

  When the distance between the EHs after the discharge port surface polishing is L1 in the drawing, when viewed from the front of the discharge port surface 105, four EH distance determination holes 108 having a large cross-sectional area can be seen as shown in the front view of the upper part of FIG.

  An example in which the polishing amount is larger than that in FIG. 2 will be described with reference to FIG.

  In this example, the illustrated EH distance L2 is smaller than the aforementioned L1. At this time, when viewed from the front of the discharge port surface 105, the EH distance determination hole 108 has two wide holes and one narrow hole.

  As described above, the liquid ejection head 101 can be identified without being disassembled by the state where the EH distance determination hole 108 remains.

  For example, if it is desired to correct the distance between EHs from FIG. 2: L1 to FIG. 8: L2, the polishing can proceed until the state of FIG. 8, that is, two wide holes and one narrow hole remain. The correction can be easily performed.

  Further, since the finished dimension from the discharge port surface 105 to the heater 103 can be identified by the appearance by the EH distance determination hole 108, it is possible to select and correct an appropriate driving condition in accordance with the distance between EHs.

  Further, since the EH distance determination hole 108 disappears in order from the inside as the correction process is advanced, the visibility is excellent, and the remaining EH distance determination hole 108 is gradually away from the discharge port 104. There is a tendency that ink droplets on the surface are difficult to pull and the influence of wettability around the ejection port 104 can be reduced.

  Further, if the EH distance determination hole 108 is formed of a photosensitive epoxy resin like the discharge nozzle 104, the periphery of the EH distance determination hole 108 is made of the same material. For example, the correction processing is performed. In this case, it is possible to prevent damage such as chipping around the hole.

  FIG. 3 is a schematic front view showing the internal structure of an embodiment of a recording apparatus 301 having the liquid ejection head 101 according to the present invention. Each of the plurality of liquid ejection heads 101K to 101Y includes an individual recovery unit 305, an ink cartridge 303, and a sub tank 304, and includes a transport unit 308, an operation panel 310, a paper feed unit 306, and the like as a common unit of the recording apparatus 301. Here, K: black, C: cyan, LC: light cyan, M: magenta, LM: light magenta, and Y: yellow are shown. The liquid discharge heads 101K to 101Y are line heads having a recording resolution of 600 [dot / inch], each having 2,560 discharge nozzles and a maximum recording width of 4.3 [inch].

  While the standby liquid ejection heads 101K to 101Y are hermetically capped by the recovery unit 305, they move out of the capped state during image recording, move downward in the figure, stand still in the vicinity of the transport unit 308, and prepare for recording.

  The transport unit 308 operates to transport the paper at a constant speed in the left direction in the figure by the transport belt.

  The sheets P stacked on the sheet feeding unit 306 are picked up one by one, fed out in the direction of the arrow on the main body side of the recording apparatus 301, and delivered to the transport unit 308.

  At the same time as passing through the lower portions of the respective liquid discharge heads 101K to 101Y, an image is recorded at a high speed and stacked on the paper discharge unit 309.

  FIG. 4 shows an image of the ink path during the recording operation.

  First, the flow of ink during the recording operation will be described with reference to FIG. 4A.

  The liquid discharge head 101 is released from the cap mechanism 305 and discharges ink at a position where the discharge port surface 105 is close to the paper P and performs a recording operation. The internal negative pressure is promoted, and ink corresponding to the amount used for recording is replenished from the sub tank 304 to the common liquid chamber 109 of the liquid discharge head 101 via the filters 402 and 403. The atmospheric communication port 206 in the sub tank 304 is open during this time, and the pressurizing pump 407 that pressurizes and supplies ink to the liquid ejection head 101 does not operate.

  Next, FIG. 4B shows a state during a recovery operation in which each discharge nozzle of the liquid discharge head 101 is maintained and recovered in a healthy state.

  The liquid discharge head 101 maintains a state where it is capped by the recovery mechanism 305 during the recovery operation.

  Ink recycling is performed to open the recycle valve 406 in advance and operate the pump 404 to return the ink staying in the ink reservoir 410 inside the recovery mechanism 305 to the sub tank 304 through the path from the discharge port to the filter 405 to the recycle valve 406 to the pump 404. Start operation.

  Thereafter, when the recovery valve 401 is closed and the pressurizing pump 407 is operated, the ink in the sub tank 304 is sent to the common liquid chamber 109 of the liquid discharge head 101 via the filter 402, but the recovery valve 401 is closed, Is rapidly pressurized and a relatively large amount of ink is forced out of each nozzle, and the nozzle is restored to a healthy state.

  The forcibly pushed ink tries to temporarily accumulate in the ink reservoir 410, but since the recycling operation by the pump 404 has already started, it is immediately collected in the sub tank.

  Although not shown, when ink is supplied from the removable ink cartridge 303 to the sub tank 304, the recycle valve 406 is closed and the supply valve 408 is opened, and then the pump 404 is driven. Then, the ink in the ink cartridge is supplied to the sub tank 304 via the supply valve 408 to the pump 404. If the ink level sensor 409 does not detect a full tank even if the supply operation is continued for a predetermined time, it is determined that the ink in the ink cartridge 303 has become empty.

  FIG. 5 is a cross-sectional perspective view of the vicinity of a nozzle that ejects ink. A heater 103 for heating and foaming a liquid is arranged for each nozzle on the heater board 502. The heater 103 is a sheet-like resistor having a thickness of 0.01 to 0.5 [μm] and a sheet resistance of 10 to 300 [Ω] per unit square. An electrode (not shown) made of aluminum or the like for energization is connected to the heater 103, and one of them is connected to a switching transistor (not shown) for controlling energization to the heater 103.

  A heater 103 is formed for each discharge nozzle 106. The discharge nozzle 106 includes a heater board 502, a nozzle wall 107, a nozzle bank 516 having a thickness of about 5 to 10 [μm], and a nozzle having a thickness of about 2 [μm]. It has a tubular shape surrounded by the top plate 517. The movable valve 512 is provided with the valve support member 513 positioned in the common liquid chamber with the free end 518 directed toward the discharge port, and the valve support member 513 is attached to the heater board 502 by a valve pedestal (not shown). The nozzle top plate 517 is affixed to a top plate 511 made of Si or the like, and the top plate 511 includes an ink supply opening 519 formed by anisotropic etching or the like, and allows liquid from the outside to be in a common liquid chamber. 109 can be introduced.

The liquid supplied from the common liquid chamber 109 to the discharge nozzle 106 is heated and foamed by the heater 103 disposed at a predetermined position in the discharge nozzle 106. Along with the foaming, the operation of the liquid in the discharge nozzle 106 starts, and at the same time, the movable valve 512 is displaced to control the liquid flow. Then, liquid is discharged from the discharge port 104.
Next, the manufacturing method of the liquid discharge head according to the present invention will be described with reference to FIGS. 6 to 7, (a-1) to (i-1) are front views as seen from the nozzle side for explaining the method of manufacturing the liquid discharge head of the present invention, and (a-2) to (i-2). ) Is a side sectional view of the vicinity of the nozzle.

  As shown in FIGS. 6A-1 and 6A-2, using the same manufacturing apparatus as used in the semiconductor manufacturing process on the element substrate (silicon wafer) B, hafnium boride, niobium boride, Alternatively, after forming the heater 103 made of tantalum nitride or the like, the surface of the element substrate B was cleaned for the purpose of improving the adhesion with the photosensitive resin film DF in the next step. Furthermore, after surface modification by ultraviolet-ozone or the like is performed on the element substrate B surface for the purpose of improving adhesion, for example, a solution obtained by diluting a silane coupling agent to 1% by weight with ethyl alcohol is spun onto the modified surface. This is achieved by coating.

  Next, surface cleaning was performed, and an ultraviolet photosensitive resin film DF1 was laminated on the element substrate B with improved adhesion as shown in FIGS. 6 (b-1) and (b-2). Next, as shown in FIGS. 6C-1 and 6C-2, a photomask M1 is arranged on the ultraviolet photosensitive resin film DF1, and a valve pedestal 601 for bonding the nozzle bank 516 and the movable valve 512 is used. The part to be left as was irradiated with ultraviolet rays. In the next step, as shown in FIGS. 6D-1 and 6D-2, the ultraviolet photosensitive resin film DF2 was laminated on the ultraviolet photosensitive resin film DF1 irradiated with ultraviolet rays. A photomask M2 is arranged on the laminated ultraviolet photosensitive resin film DF2 and is left as a nozzle wall 507 and a liquid chamber frame (not shown) as shown in FIGS. 6 (e-1) and 6 (e-2). Irradiate ultraviolet rays. Subsequently, as shown in FIGS. 7 (f-1) and (f-2), the ultraviolet photosensitive resin films DF1 and DF2 are developed with a developer composed of a mixed solution of xylene and butyl cellosolve acetate, and the unexposed portions are removed. The melted, exposed and cured portions were formed as a nozzle bank 516, a valve seat 601, a nozzle wall 507, and a liquid chamber frame (not shown). After forming the nozzle bank 516, the valve pedestal 601, the nozzle wall 507 and the liquid chamber frame (not shown), the movable valve 512 is placed on the valve pedestal 601 as shown in FIGS. 7 (g-1) and (g-2). Fix with adhesive. After that, as shown in FIGS. 7 (h-1) and (h-2), the top plate 511, which is previously laminated with the nozzle top plate 517 made of a photosensitive resin film, is replaced with the nozzle top plate 517 and the liquid chamber frame ( (Not shown).

  By the above method, it is possible to uniformly form the periphery of the discharge port with the same resin material with respect to the plurality of heater boards divided and manufactured from the element substrate B. Then, the element substrate B was cut and separated into each heater board as shown in FIGS. 7 (i-1) and (i-2) with a dicing machine to which a diamond blade having a thickness of 0.05 [mm] was attached. Next, the liquid discharge port surface 105 of the separated heater board is polished while applying a certain pressure to smooth the discharge port surface 105.

The heater board 502 obtained in this way is supported by a ceramic base plate 1200 as shown in FIG. A mounted PCB (wiring board) 1202 is supported by a double-sided tape behind the heater board 502 on the base plate 1200, and the heater 103 and the PCB 1202 on the heater board 502 correspond to each wiring by wire bonding 1201. Are electrically connected.
(Example 2)
FIG. 9 is a cross-sectional top view of the liquid discharge head 901 in the present invention. In FIG. 9, each of the discharge nozzles 906 communicating with the discharge port 904 has a heater 903 for heating the liquid, and the liquid is discharged from the discharge port 904 by heating and foaming the liquid with the heater 903.

  The plurality of discharge nozzles 906 communicate with the common liquid chamber 109, and the common liquid chamber 109 is formed by a liquid chamber frame 910.

  In addition, a plurality of types of holes 908 (hereinafter referred to as EH (Edge-Heather) distance determination holes) for indicating the distance from the discharge port surface 905 to the heater 903 are described at the row end portions of the arranged discharge nozzles 104. ) Is provided.

  In addition to the EH distance determination hole 908, the hole 20 for determining the distance from the discharge port surface 905 to the heater 903 as an auxiliary (hereinafter referred to as an extinction EH distance determination hole) is provided in the center of the nozzle row. Is provided).

  10 and 11 are an enlarged top view and a front view of the periphery of the EH distance determination hole 908 (part A ′ in FIG. 9) and the periphery of the disappearance EH distance determination hole 920 (part A ″ in FIG. 9). When the distance between EHs is the target L1 (FIG. 10), when viewed from the front of the discharge port surface 5, four wide EH distances are wide on the side of the nozzle row as shown in the upper front view. The determination hole 908 is visible, and the annihilation EH distance determination hole 20 is polished and is not visible in the center of the nozzle row.

  On the other hand, when the distance between EHs is L3 (L3> L1), as shown in the front view of FIG. It has become. Therefore, in order to obtain the target EH distance L1, the four EH distance determination holes 908 having a wide width are formed in the side of the nozzle row when viewed from the front view of FIG. In addition, the discharge port surface 905 may be corrected by polishing or the like until the disappearance EH distance determination hole 920 becomes invisible at the center of the nozzle row, and the correction processing can be performed very easily. .

  In this embodiment, there is one annihilation EH distance determination hole 920 at the center of the nozzle row, but the position and number of the holes are not limited thereto.

  The liquid discharge head of the present invention can be used for a high-speed and high-quality color printer or the like.

It is a cross-sectional top view of the liquid discharge head in the present invention. FIG. 6 is a top view and a front view of the vicinity of a hole provided at an end of an ejection nozzle row of the liquid ejection head according to the first embodiment of the present invention. FIG. 3 is a front view of a recording apparatus using the liquid discharge head according to the present invention. It is the schematic which shows the ink flow path of the said recording device. It is a cross-sectional perspective view of the vicinity of the liquid ejection head in the present invention. It is a manufacturing process figure of the liquid discharge head in the present invention. FIG. 7 is a manufacturing process diagram for the head subsequent to FIG. 6. FIG. 3 is a top view of the vicinity of a hole provided at an end of a discharge nozzle row of the liquid discharge head according to the first embodiment of the present invention. It is the top view and front view of the vicinity of the hole provided in the discharge nozzle row | line | column edge part and center part by 2nd Example of this invention. It is the top view and front view of the vicinity of the hole provided in the discharge nozzle row | line | column edge part and center part by 2nd Example of this invention. It is the top view and front view of the hole vicinity provided in the discharge nozzle row center part by 2nd Example of this invention. FIG. 3 is a side sectional view of a liquid discharge head according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Liquid discharge head 103 Heater 104 Discharge port 105 Discharge port surface 106 Nozzle 107 Nozzle wall 108 EH distance determination hole 109 Common liquid chamber 110 Liquid chamber frame

301 Recording Device 303 Ink Cartridge 304 Subtank 305 Recovery Mechanism (Cap Mechanism)

401 Recovery valve 404 Pump 406 Recycling valve 407 Pressurizing pump 408 Supply valve


502 Heater board 516 Nozzle bank 517 Nozzle top plate



908 Distance determination hole between EH 920 Distance determination hole between annihilation EH

Claims (8)

In a liquid discharge head having a heater for heating a liquid in a discharge nozzle communicated with the discharge port, and discharging the liquid from the discharge port by heating and foaming the liquid with the heater,
A liquid discharge head, wherein a plurality of recesses having different depths are provided on the discharge port surface, and the polishing amount is displayed stepwise by the shape of the recess remaining after polishing of the discharge port surface. The liquid ejection head according to claim 1, wherein each of the plurality of recesses is formed of a plurality of recesses having different depths. The liquid discharge head according to claim 2, wherein the depth of the concave portion increases as the distance from the discharge nozzle row increases. The liquid discharge head according to claim 1, wherein a plurality of sets of the plurality of concave portions are provided. The liquid discharge head according to claim 1, wherein peripheral portions of the plurality of recesses are made of the same material, and the material is a photosensitive epoxy resin. 5. The liquid ejection head according to claim 1, further comprising a concave portion that disappears when a predetermined amount is polished apart from the plurality of concave portions. 6. The liquid discharge head according to claim 1, wherein the concave shape remaining after the polishing process indicates a distance from the heater to the discharge port in a stepwise manner. The liquid discharge head according to claim 1, further comprising a movable valve in the vicinity of the heater in the discharge nozzle.

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