JP2006281737A - Inkjet recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long inkjet recording head highly reliable in electrical connection. <P>SOLUTION: In the inkjet recording head, a recording element substrate wherein a plurality of nozzles for discharging a liquid and a plurality of recording elements for generating discharge energy are arrayed, and a wiring substrate attached to a second supporting board, are arranged on a first supporting board, while the recording element substrate and the wiring substrate are electrically connected. The first supporting board and the second supporting board with the wiring substrate attached thereto are retained by a member having a rigidity. The highly reliable inkjet recording head is provided thereby. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording head that performs a recording operation by discharging a liquid such as ink. In particular, the configuration of an ink jet recording head that includes a support plate, a recording element substrate, and a wiring substrate and is electrically connected is suitably applied to a recording apparatus that performs high-speed and high-quality printing.

  Conventionally, an inkjet recording apparatus is low in running cost, can be downsized, and can easily support color image recording using a plurality of colors of ink. Widely used and commercialized.

  On the other hand, as an energy generating element that generates energy for ejecting ink from the ejection port of the recording head, an element that uses an electromechanical transducer such as a piezo element, or an electromagnetic wave such as a laser emits heat to generate heat. There are those that discharge ink droplets by the action of, and those that heat a liquid by an electrothermal conversion element having a heating resistor.

  Among them, an inkjet recording system head that uses thermal energy to eject ink droplets can arrange discharge ports at high density, and therefore can perform high-resolution recording. Recording heads that use electrothermal transducers as energy generating elements are also available in smaller sizes, and are sufficient for the advantages of IC technology and micromachining technology that have made significant progress in technology and improved reliability in the recent semiconductor field. This is advantageous because it can be used in high density, easy to mount with high density, and inexpensive to manufacture.

  Recently, in order to perform higher-detail printing, a method of creating a nozzle for ejecting ink with high accuracy using a photolithographic technique has been used.

In recent years, in order to realize high-detail image recording at higher speed, it is also desired to realize a recording head having a longer print width. Specifically, a head having a length of 4 inches to 13 inches or the like has been required, and development is progressing.
JP 2001-13001 A

  As the head becomes longer in this way, the influence of elongation due to the difference in the linear expansion coefficient between the members becomes increasingly greater. In particular, the difference in elongation between the first support plate on which the recording element substrates are arranged and the second support plate that supports the wiring substrate and the wiring substrate is fatal in terms of reliability.

  Conventionally, alumina has been used as the first support plate. Also, as the second support plate, metal such as SUS or Ni is used from the viewpoint of workability and cost, and the first support plate and the second support plate are fixed only by an adhesive. . Further, since the adhesive is used in a state where the recording element substrate is disposed, there is a restriction that the adhesive cannot be cured at a high temperature due to the heat resistance problem of the recording element substrate. For this reason, it is difficult to completely restrain the difference in elongation between the first support plate and the second support plate due to temperature changes due to the use of the head and changes in environmental temperature. there were. As a result, there is a problem that stress is generated in the connection portion between the recording element substrate and the wiring substrate, leading to disconnection of the connection portion.

  SUMMARY OF THE INVENTION In view of the above-described problems of the prior art, an object of the present invention is to provide a head that is low in cost and has high electrical connection reliability.

  In order to achieve the above object, an ink jet recording head of the present invention includes a first support plate in which a plurality of nozzles for discharging liquid and a plurality of recording elements for generating discharge energy are arranged, and a first support plate for supporting a wiring board. The second support plate is restricted in extension by a rigid member.

  Further, the first invention of the present invention will be described as follows.

  (1) A recording element substrate in which a plurality of nozzles for discharging liquid and a plurality of recording elements for generating discharge energy are arranged on a first support plate, and a wiring substrate attached to the second support plate In the inkjet recording head in which the recording element substrate and the wiring substrate are electrically connected and connected, the first support plate and the second support plate to which the wiring substrate is attached have rigidity. An ink jet recording head that is restrained by a member.

  In the present invention, the first support plate on which the recording element substrate of the ink jet recording head is arranged and the second support plate to which the electric wiring substrate is attached are fixed by a rigid member, so that the connection portion due to temperature change The ink jet recording head with high reliability can be provided.

  Next, embodiments of the present invention will be described with reference to the drawings.

  1 to 4 are explanatory views for explaining a suitable recording head to which the present invention is applied or applied. Hereinafter, description will be given with reference to these drawings.

  As shown in FIG. 1, the recording head H1000 is a bubble that performs recording using an electrothermal transducer that generates thermal energy for generating thermal energy for causing film boiling to the ink in response to an electrical signal. The recording head is a jet (registered trademark) side shooter type.

  As shown in the exploded perspective view of FIG. 2, the recording head H1000 includes a recording element unit H1001 and an ink supply member H1500 of an ink supply unit H1002. Further, as shown in the exploded perspective view of FIG. 3, the recording element unit H1001 includes a recording element substrate H1100, a first support plate H1200, an electric wiring substrate H1300, a second support plate H1400, and a filter member H1600. Yes.

  FIG. 4A is a diagram for explaining the configuration of the recording element substrate H1100, and FIG. 4B is a cross-sectional view taken along line AA shown in FIG. The recording element substrate H1100 has a thin film formed of, for example, a Si substrate H1108 having a thickness of 0.5 to 1 mm. Further, an ink supply port H1101 consisting of a long groove-like through-hole is formed as an ink flow path, and electrothermal conversion elements H1102 are arranged in a staggered pattern on each side of the ink supply port H1101, respectively. The element H1102 and electric wiring such as Al are formed by a film forming technique. An electrode H1103 is provided to supply power to the electrical wiring. The ink supply port H1101 performs anisotropic etching using the crystal orientation of the Si substrate H1108. When the wafer surface has a crystal orientation of <100> and a thickness direction of <111>, the etching proceeds at an angle of about 54.7 degrees by alkaline etching (KOH, TMAH, humanradine, etc.) anisotropic etching. . Using this method, etching is performed to a desired depth. A nozzle plate H1110 is provided on the Si substrate H1108, and an ink flow path H1104, a nozzle H1105, and a foaming chamber H1107 corresponding to the electrothermal conversion element H1102 are formed by a photolithography technique. The nozzle H1105 is provided so as to face the electrothermal conversion element H1102, and causes the ink supplied from the ink supply port H1101 to generate bubbles by the electrothermal conversion element H1102 to discharge the ink. .

The first support plate H1200 is made of, for example, an alumina (Al ₂ O ₃ ) material having a thickness of 0.5 to 10 mm. The material of the first support plate is not limited to alumina, and has a linear expansion coefficient equivalent to the linear expansion coefficient of the material of the recording element substrate H1100, and the thermal conductivity of the recording element substrate H1100 material. It may be made of a material having the same or higher thermal conductivity. The material of the first support plate H1200 is, for example, any of silicon (Si), aluminum nitride (AlN), zirconia, silicon nitride (Si3N4), silicon carbide (SiC), molybdenum (Mo), and tungsten (W). There may be. The first support plate H1200 is formed with an ink supply port H1201 for supplying ink to the recording element substrate H1100. The ink supply port H1101 of the recording element substrate H1100 is the ink supply port of the first support plate H1200. The recording element substrate H1100 corresponds to H1201 and is bonded and fixed to the first support plate H1200 with high positional accuracy.

  The adhesive is desirably, for example, a material having a low viscosity, a thin adhesive layer formed on the contact surface, a relatively high hardness after curing, and ink resistance. For example, it is a thermosetting adhesive mainly composed of an epoxy resin, or an ultraviolet curing combined thermosetting adhesive, and the thickness of the adhesive layer is desirably 50 μm or less. The first support plate H1200 has an X-direction reference H1204, a Y-direction reference H1205, and a Z-direction reference H1206, which are positioning references.

  As shown in FIG. 1, the recording element substrates H1100 are arranged in a staggered manner on the first support plate H1200 to enable wide recording with the same color. For example, four recording element substrates H1100a, H1100b, H1100c, and H1100d each having a nozzle group length of 1 inch + α are arranged in a staggered manner to enable recording of a width of 4 inches.

  In addition, the end of each ejection element group of each recording element substrate is provided with a region (L) overlapping with the end of the nozzle group of the recording element board adjacent to the staggered pattern in the recording direction. Prevents gaps from being generated by printing. For example, overlapping regions H1109a and H1109b are provided in the nozzle group H1106a and the nozzle group H1106b.

  The electrical wiring substrate H1300 applies an electrical signal for ejecting ink to the recording element substrate H1100, has an opening for incorporating the recording element substrate H1100, and has a second surface on the back surface. The support plate H1400 is bonded and fixed. The electric wiring board H1300 has an electrode terminal H1302 corresponding to the electrode H1103 of the recording element board H1100, and an external signal input terminal H1301 for receiving an electric signal from the recording apparatus main body located at the end of the wiring. Yes. The electrical wiring substrate H1300 and the recording element substrate H1100 are electrically connected. For example, the electrode H1103 of the recording element substrate H1100 and the electrode terminal H1302 of the electrical wiring substrate H1300 are connected to a gold wire H1303 (not shown). It is electrically connected by the wire bonding technique used. As a material of the electrical wiring board H1300, for example, a flexible wiring board having a two-layer structure is used, and a surface layer is covered with a polyimide film.

  The second support plate H1400 is formed of, for example, a SUS plate having a thickness of 0.5 to 1 mm. Note that the material of the second support plate is not limited to SUS, and may be made of a material having ink resistance and good flatness. The second support plate H1400 has a recording element substrate H1100 bonded and fixed to the first support plate H1200 and an opening for taking in the recording element substrate, and is bonded and fixed to the first support plate.

  A groove formed by the opening H1402 of the second support plate and the side surface of the recording element substrate H1100 is filled with the first sealing agent H1304, and the electrical mounting portion of the electrical wiring substrate H1300 is sealed. . Further, the electrode H1103 of the recording element substrate is sealed with a second sealant H1305 to protect the electrical connection portion from corrosion by ink and external impact.

  A filter member H1600 for removing foreign matter mixed in the ink is bonded and fixed to the back surface side ink supply port H1201 of the first support plate H1100.

  The ink supply member H1500 is formed by resin molding, for example, and includes a common liquid chamber H1501 and a Z-direction reference surface H1502. The Z reference plane H1502 positions and fixes the recording element unit and serves as the Z reference for the recording head H1000.

  As shown in FIG. 2 described above, the recording head H1000 is completed by coupling the recording element unit H1001 to the ink supply member H1500.

  The coupling is performed as follows.

  The opening of the ink supply member H1500 and the recording element unit H1001 are sealed with a third sealant H1503, and the common liquid chamber H1501 is sealed. Then, the Z reference H1502 of the recording element unit H1001 is positioned and fixed to the Z reference H1502 of the ink supply member by, for example, a screw H1900. The third sealant H1503 is desirably a sealant that has ink resistance, is cured at room temperature, and can withstand the linear expansion difference between different materials.

  Further, the external signal input terminal H1301 portion of the recording element unit H1001 is positioned and fixed on the back surface of the ink supply member H1501, for example.

  The material of the support substrate is preferably a material having ink resistance and good thermal conductivity, such as alumina or carbon graphite.

  5A and 5B are schematic views for explaining the manufacturing process of the ink jet recording head according to the present invention, FIG. 6A is a plan view of the intermediate process, and FIG. 5B is a cross-sectional view taken along the line CC in FIG. . The first support plate H1200 is previously drilled and SUS pins are driven in. The recording element substrate H1100 is arranged with high accuracy. The electric wiring board affixed on the 2nd support plate H1400 is affixed on this. The second support plate H1400 is drilled so as to fit into the pins driven into the first support plate H1200, and together with the adhesive, the first support plate H1200 and the first support plate H1200 are connected to each other by pin hole fitting. The second support plate H1400 is restrained so as not to be displaced. Further, as shown in FIG. 6B, part D is preferably disposed in the vicinity of the portion where the recording element substrate H1100 and the electrical wiring substrate H1300 are connected, as the location where the pins are installed.

  FIG. 7 shows another embodiment of the present invention, which is illustrated so as to see through the electric wiring board H1300. As shown in FIG. 7E, the stress generated between the first support plate H1200 and the second support plate H1400 can be further reduced by dividing the second support plate.

  FIG. 8 shows another embodiment of the present invention. In the figure, 200 is a jig upper mold, and 300 is a jig lower mold.

  The first support plate H1200 is drilled. A second support plate H1400 having a wiring substrate attached thereto is attached thereto. As shown in FIG. 8A, this is set so that the convex portion of the lower mold 300 of the jig is inserted into the hole of the first support plate H1400 and positioned. The lower mold 300 and the upper mold 200 of the jig are accurately adjusted, and the second support plate H1400 positioned in the hole of the first support plate H1200 is pressed by the upper mold (see FIG. 8 (b)). Thereby, the first support plate H1200 and the second support plate H1400 are restrained so as not to be displaced (FIG. 8C).

External perspective view of recording head of the present invention 1 is an exploded perspective view of a recording head of the present invention. Exploded perspective view of recording element unit It is a figure explaining a recording element board | substrate, (a) Perspective view, (b) AA sectional drawing The figure explaining the manufacturing process of the recording head of this invention The figure explaining the Example of this invention The figure explaining the other Example of this invention FIG. 4 is a partial view illustrating another embodiment of the present invention.

Explanation of symbols

H1000 Recording head H1001 Recording element unit H1002 Ink supply unit H1100 Recording element substrate H1101 Ink supply port H1102 Electrothermal conversion element H1103 Electrode H1104 Ink flow path H1105 Nozzle H1106 Nozzle group H1107 Foaming chamber H1108 Si substrate H1110 Nozzle plate H1200 First support plate H1201 Ink supply port H1204 X direction reference H1205 Y direction reference H1206 Z direction reference H1300 Electric wiring board H1301 External signal input terminal H1302 Electrode terminal H1303 Gold wire H1304 First sealant H1305 Second sealant H1400 Second support Plate H1500 Ink supply member H1501 Liquid chamber (not shown)
H1502 Z reference plane H1503 Third sealant (not shown)
H1504 Ink supply port (not shown)
H1800 ink tank H1900 screw

Claims (5)

  On the first support plate, a recording element substrate in which a plurality of nozzles for discharging liquid and a plurality of recording elements for generating discharge energy are arranged, and a wiring substrate attached to the second support plate are arranged, In the inkjet recording head in which the recording element substrate and the wiring substrate are electrically connected and connected, the first support plate and the second support plate to which the wiring substrate is attached are restrained by a rigid member. An ink jet recording head characterized by the above.   2. An ink jet recording head according to claim 1, wherein a plurality of recording element substrates on which a plurality of nozzles for discharging liquid and a plurality of recording elements for generating discharge energy are arranged are arranged on the support plate in the nozzle arrangement direction.   3. The ink jet recording head according to claim 1, wherein the ink jet recording head is a fitting of a pin and a hole.   3. The ink jet recording head according to claim 1, wherein the restraining member is in the vicinity of an electrical connection portion of each recording element substrate.   The inkjet recording head according to claim 2, wherein the second support plate is divided into a plurality of parts.

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