JP2012006327A - Liquid jet head and liquid jet apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet head and a liquid jet apparatus which can prevent the softening, deformation, swelling or the like of a flow passage when liquid is distributed in a flow passage formed at a flow passage member.SOLUTION: The liquid jet head includes a liquid jet head body 20 which jets a liquid droplet through a nozzle opening by generating pressure fluctuation in a pressure generation chamber 23 by a pressure generating means; and the flow passage member 10 fixed on the liquid jet head body and having the flow passage for supplying liquid to the liquid jet head body. A tubular member 61 for covering an inner circumferential surface is arranged on the inner circumferential surface of the flow passage formed in the flow passage member.

Description

  The present invention relates to a liquid ejecting head and a liquid ejecting apparatus.

Conventionally, there has been known a liquid ejecting head that ejects liquid droplets from a nozzle by applying pressure to the liquid by pressure generating means such as a piezoelectric element or a heat generating element. As a typical example, ink droplets are ejected from a nozzle. An ink jet type recording head for jetting may be used. As a liquid ejecting head main body used for such an ink jet recording head, for example, a nozzle plate having a nozzle opening formed therein is joined to a flow path forming substrate in which a pressure generating chamber is formed. The ink jet recording head main body is fixed to the cartridge case,
It is positioned and fixed to a fixed plate, thereby constituting an ink jet recording head (
For example, see Patent Document 1).

Japanese Patent Laying-Open No. 2005-096419

The cartridge case described in Patent Document 1 has a complicated shape, and needs to be formed of a resin in consideration of moldability, workability, and production cost. However, when the cartridge case is formed of resin, depending on the solvent contained in the ink, the flow path of the cartridge case may be softened, deformed, or swollen.

Such a problem exists not only in an ink jet recording head that ejects ink but also in a liquid ejecting head that ejects another liquid.

The present invention has been made in view of such circumstances, and a liquid that can prevent softening, deformation, swelling, and the like of the flow path when the liquid flows through the flow path formed in the flow path member. It is an object of the present invention to provide an ejection head and a liquid ejection apparatus in which ejection characteristics do not change.

The liquid ejecting head of the present invention includes a liquid ejecting head main body that causes a pressure fluctuation in a pressure generating chamber by a pressure generating means to eject liquid droplets through a nozzle opening, and the liquid fixed on the liquid ejecting head main body. A flow path member having a flow path for supplying the liquid to the ejection head body, and a tubular member covering the inner peripheral surface is provided on the inner peripheral surface of the flow path formed inside the flow path member. It is characterized by being. In the present invention, by providing the tubular member, it is possible to prevent softening, deformation, swelling, and the like due to the liquid flowing through the flow path of the flow path member.

As a preferred embodiment of the present invention, the tubular member is provided by being inserted into the flow path, or the tubular member is formed in the flow path by integral molding when the flow path is formed. And provided. The “tubular member” in the present invention does not include those provided by plating.

The tubular member is preferably glass. Glass does not have moldability enough to form a flow path member, but is particularly resistant to highly acidic liquids. Therefore, the flow path member is formed of a highly moldable resin, and the flow path itself is formed. By protecting with a tubular member, softening, deformation, swelling, etc. of the flow path of the flow path member can be prevented.

The liquid ejecting apparatus of the invention includes any one of the liquid ejecting heads. By providing the tubular member, the flow path of the flow path member can be prevented from being softened, deformed, swelled, and the like, whereby a liquid ejecting apparatus in which the liquid ejection characteristics do not vary can be obtained.

1 is a schematic perspective view of a recording apparatus according to an embodiment. FIG. 2 is an exploded perspective view of a recording head according to an embodiment. FIG. 3 is an assembled perspective view of a recording head according to an embodiment. FIG. 3 is a cross-sectional view of a main part of a recording head according to an embodiment. 2 is a plan view of a recording head body according to an embodiment. FIG.

Hereinafter, the present invention will be described in detail based on embodiments.
FIG. 1 is a schematic perspective view of an ink jet recording apparatus which is an example of a liquid ejecting apparatus according to an embodiment of the invention.

The liquid ejecting apparatus according to the present embodiment is, for example, an ink jet recording apparatus, and as illustrated in FIG. 1, an ink jet recording head (hereinafter referred to as a recording head) having an ink jet recording head main body (hereinafter referred to as a recording head main body). 1) an ink cartridge 2 constituting the ink supply means is detachably provided, and a carriage 3 on which the recording head 1 is mounted is provided on a carriage shaft 5 attached to the apparatus body 4 so as to be axially movable. Yes. Then, the driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head 1 is mounted is moved along the carriage shaft 5. On the other hand, the apparatus main body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S, which is a recording medium such as paper fed by a not-shown paper feed roller, is conveyed on the platen 8. It is like that.

In addition, a cap member 9 that seals the nozzle surface where the nozzles of the recording head 1 open is provided at a position corresponding to the home position of the carriage 3, that is, near one end of the carriage shaft 5. The cap member 9 seals the nozzle surface of the recording head 1 to prevent the ink in the vicinity of the nozzles of the recording head 1 from being dried and, for example, a flushing operation for ejecting ink droplets from the nozzles or a predetermined amount. It functions as an ink receiver during a suction operation in which the inside of the cap member 9 is sucked by the suction means at a timing to forcibly discharge ink or the like from the nozzles.

Next, the configuration of an ink jet recording head that is an example of a liquid ejecting head will be described. FIG. 2 is an exploded perspective view showing an example of the recording head, and FIG. 3 is an assembled perspective view thereof.

As shown in FIGS. 2 and 3, the recording head 1 includes a flow path member 10, a recording head body 20 that is an example of a liquid ejecting head body, and a nozzle face of the recording head body 20. And a fixing plate 50 on which positioning is fixed.

In this embodiment, the flow path member 10 is formed of a resin material, and has a cartridge mounting portion 11 to which an ink cartridge (not shown) is mounted. The cartridge mounting portion 11
The ink supply needle 12 to be inserted into the ink cartridge is fixed. Note that FIG.
Although not shown in FIG. 3, these ink supply needles 12 are provided with ink introduction paths for supplying ink to the recording head main bodies 20.

A plurality of (four in the present embodiment) recording head bodies 20 positioned at a predetermined interval are fixed to the bottom surface of the flow path member 10 to constitute the recording head 1. Each recording head body 20
Are provided for each color ink. Further, the recording head main bodies 20 are fixed to the bottom surface of the flow path member 10 in a state where they are positioned with respect to each other by being bonded and fixed to the fixing plate 50.

4 is a cross-sectional view showing the main part of the recording head, and FIG. 5 is a plan view of the recording head main body.

As shown in FIGS. 4 and 5, in the recording head 1 according to this embodiment, the flow path member 10 includes a holder head 21 and a head case 22 joined to the holder head 21. A head case 22 is joined on each recording head body 20. The recording head body 20 includes first to third flow path forming substrates 24 to 26 made of an insulating material in which an ink flow path including a pressure generation chamber 23 is formed.

The first flow path forming substrate 24 is formed with a plurality of pressure generating chambers 23 that constitute a part of the ink flow path. For example, in the present embodiment, as shown in FIG. 4, the first flow path forming substrate 24 has a row in which the pressure generation chambers 23 are arranged in parallel in the width direction (short direction) of the pressure generation chambers 23. Two rows are formed. The first flow path forming substrate 24 includes a first reservoir portion 28 constituting a reservoir 27 serving as a common ink chamber of each pressure generating chamber 23 on the outside in the longitudinal direction of the pressure generating chambers 23 of each row, An ink supply path 29 that connects the first reservoir 28 and each pressure generating chamber 23 is formed.

A plurality of nozzles 30 corresponding to the pressure generation chambers 23 are provided on one surface side of the first flow path forming substrate 24.
A nozzle plate 31 made of, for example, stainless steel is fixed by an adhesive, a heat welding film, or the like. Although not shown, a water repellent film is formed on the surface of the nozzle plate 31 where the nozzles 30 are opened, thereby suppressing ink adhesion.

On the other surface side of the first flow path forming substrate 24, for example, an elastic film 32 made of an oxide film is formed. On the elastic film 32, a piezoelectric element 36 including a first electrode 33, a piezoelectric layer 34, and a second electrode 35 is formed corresponding to each pressure generating chamber 23. In addition, a lead electrode 37 is connected to the second electrode 35 of each piezoelectric element 36.
A voltage is selectively applied to the piezoelectric element 36 via the.

The second flow path forming substrate 25 is bonded to the elastic film 32 side surface of the first flow path forming substrate 24 on which such a piezoelectric element 36 is formed. The second flow path forming substrate 25 includes each piezoelectric element 3.
Each of the piezoelectric elements 36 is formed with a piezoelectric element holding portion 38 in a region facing the six rows.
Is accommodated in the piezoelectric element holding portion 38. Further, as described above, the second flow path forming substrate 25 is formed with two second reservoir portions 39 communicating with the first reservoir portions 28 of the first flow path forming substrate 24, respectively. .

Furthermore, in the present embodiment, a third flow path forming substrate 26 is bonded onto the second flow path forming substrate 25. On the third flow path forming substrate 26, two third reservoir portions 40 communicating with each of the second reservoir portions 39 are formed. In the present embodiment, these third reservoir portions 40 are continuously formed up to a portion facing the piezoelectric element holding portion 38 provided on the second flow path forming substrate 25, and have a relatively large capacity. The ink can be stored. Each reservoir 27 is constituted by these first to third reservoir portions 28, 39, and 40, and a capacity for storing sufficient ink to be supplied to each pressure generating chamber 23 is secured.

Here, for example, in the present embodiment, the first to third flow path forming substrates 24 to 26 are made of a silicon single crystal substrate, and the pressure generating chamber 23 and the first to third reservoir portions 28, 39, 40 etc. are formed by anisotropically etching these first to third flow path forming substrates 24 to 26.

A sheet plate 43 including a sealing film 41 and a fixed substrate 42 is bonded onto the third flow path forming substrate 26. The sealing film 41 is made of a material having low rigidity and flexibility, such as a PPS film, and the one surface of the third reservoir section 40 is sealed by the sealing film 41. The fixed substrate 42 is made of a conductive and relatively hard material such as SUS. Since the region facing the third reservoir 40 of the fixed substrate 42 is an opening 44 that is completely removed in the thickness direction, one surface of the third reservoir 40 has flexibility. It is sealed only with the sealing film 41. Further, the sheet plate 43 is formed with an ink introduction port 45 communicating with each reservoir 27. In the present embodiment, these ink inlets 45 are arranged in the vicinity of the end surface of the third reservoir section 40 on the center side.

The second and third flow path forming substrates 25 and 26 and the central portion of the sheet plate 43, that is, the portion corresponding to the space between the reservoirs 27, the second and third flow path forming substrates 25 and 26 and the sheet. A through-hole 46 that penetrates the plate 43 in the thickness direction is provided. In the present embodiment, the above-described lead electrode 37 is connected to the penetrating portion 4 from the first electrode 33 and the second electrode 35 of the piezoelectric element 36.
Although not shown, external wiring made of FPC or the like is connected to these lead electrodes 37. A driving IC is mounted on the external wiring, and each piezoelectric element 36 is driven based on a signal from the driving IC.

A plurality of such recording head bodies 20, four in the present embodiment, are fixed to the fixed plate 50 while being positioned at a predetermined interval. Note that the fixing plate 50 is provided with openings 51 that expose the nozzles 30, for example, corresponding to the recording head main bodies 20. Further, a side wall portion 52 having the same height as the recording head main body 20 is provided on the peripheral edge portion of the fixed plate 50. That is, the fixing plate 50 according to the present embodiment is formed in a substantially box shape with one side opened, and has a recess 53 defined by the side wall 52 (see FIG. 2). The nozzle plate 31 of each recording head body 20 is fixed to the bottom surface of the concave portion 53 of the fixed plate 50.

Further, a head case 22 made of, for example, a resin material is joined on the sheet plate 43 constituting the recording head main body 20. The head case 22 is the recording head main body 2.
In addition to being joined to 0, it is also joined to the holder head 21. The head case 22 is provided with a lower ink introduction path 47 that is a flow path that communicates with the ink introduction port 45 and supplies ink from an ink storage unit such as an ink cartridge to the reservoir 27. The lower ink introduction path 47 communicates with the upper ink introduction path 14 provided in the holder head 21. The upper ink introduction path 14 communicates with the ink supply needle 12. That is, the ink supplied to the ink supply needle 12 is introduced into the recording head main body 20 via the upper ink introduction path 14 and the lower ink introduction path 47 (hereinafter referred to as the ink introduction path 60).

The ink introduction path 60 is provided with a tubular member 61 that covers the inner peripheral wall thereof. Tubular member 6
1 is inserted into the ink introduction path 60 by press-fitting in this embodiment, and no gap exists between the tubular member 61 and the ink introduction path 60 in this embodiment. The ink introduced into the ink introduction path 60 circulates inside the tubular member 61. The tubular member 61 will be described in detail below.

The tubular member 61 is a tubular upper tubular member 6 inserted into the upper ink introduction path 14 by press-fitting.
2 and a tubular lower tubular member 63 inserted into the lower ink introduction passage 47 by press fitting. The upper tubular member 62 and the lower tubular member 63 are configured so that ink flowing through the tubular member 61 does not leak. For example, the upper tubular member 62 and the lower tubular member 63 may be bonded with an adhesive (not shown) or may be sealed with a seal member. In this embodiment, separate tubular members are inserted into the upper ink introduction path 14 and the lower ink introduction path 47, respectively. However, after the holder head 21 and the head case 22 are joined, the upper ink introduction path 14 and the lower ink introduction path. One tubular member may be provided across the path 47.

Here, the tubular member 61 is formed with resistance to the ink used. That is,
The holder head 21 and the head case 22 are each formed of a resin material as described above. This is because even if it is a complicated shape such as the holder head 21 and the head case 22, it can be formed by molding. However, even if a resin material suitable for molding is used, some resin materials have low resistance to a specific solvent. When solvent ink containing such a specific solvent is circulated, the resin material swells in the flow path. There are cases where problems such as softening, deformation, and dissolution may occur, and this causes, for example, flow path resistance to change, which must be prevented.

Therefore, in the present embodiment, a resin material suitable for molding is used for the holder head 21 and the head case 22 and the tubular member 61 made of a material resistant to the circulating ink is used for the ink introduction path 60. By providing it, problems such as swelling, softening, deformation, and dissolution of the resin constituting the inner wall of the ink introduction path 60 are prevented. In other words, since the tubular member 61 can be formed of a resin or metal having low moldability, the holder head 21 and the head case 22 themselves are made of a resin that is easy to mold and is resistant to ink. The tubular member 61 can be formed of a certain material. Therefore, problems such as swelling, softening, deformation, and dissolution of the resin constituting the inner wall of the ink introduction path 60 are prevented and material selectivity is improved.

The tubular member 61 may be made of metal, resin, ceramic, or the like, and may be made of a material that is highly resistant to the ink used as described above. Examples of metals include iron, chrome, gold, silver,
Examples thereof include copper, aluminum, nickel, and alloys containing one of these (for example, SUS). Examples of the resin include thermosetting resins such as phenol resin, epoxy resin, melamine resin, unsaturated polyester resin, alkyd resin, and polyurethane, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polytetra Fluoroethylene, ABS resin, acrylic resin, polyamide, polyacetal, polycarbonate, modified polyphenylene ether, polybutylene terephthalate, polyethylene terephthalate, cyclic polyolefin, polyphenylene sulfide, polysulfone,
Examples thereof include thermoplastic resins such as polyether sulfone, thermoplastic polyimide, polyamideimide, and polyarylate. Examples of the ceramic include glass, alumina and zirconia.

In addition, as the ink in the above-described embodiment, an ink containing at least one selected from diethylene glycol, dimethyl ether, lactone, diethylene glycol ethyl methyl ether, tetraethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol ethyl methyl ether is used. be able to.

As solvent ink, gamma butyrolactone, diethylene glycol diethyl ether,
When either diethylene glycol methyl ethyl ether or tetraethylene glycol dimethyl ether is used as a solvent, materials that can be used for the tubular member 61 include polyarylate, polyethylene, polyethylene terephthalate, polyacetal, polypropylene, polyphenylene sulfide, and modified. Examples include polyphenylene ether (containing polyphenylene sulfide), gold, silver, copper, iron, chromium, and SUS. In this case, materials that can be used for the holder head 21 and the head case 22 include A
Examples include BS resin, polycarbonate, acrylic resin, modified polyphenylene ether (containing polystyrene), and polystyrene.

In this embodiment, an ink composed of an oil-based ink composition containing 0.02 to 4 parts by weight of a lactone solvent with respect to 1 part by weight of polyoxyethylene glycol dialkyl ether is used, and the holder head 21 and Both head cases 22 are made of modified polyphenylene ether, and the tubular member 61 is made of polyethylene.

Further, as shown in the present embodiment, the tubular member 61 is provided separately from the holder head 21 and the head case 22, so that even if the holder head 21 and the head case 22 are damaged by impact, the ink is introduced. The impact is not transmitted to the tubular member 61 in the path 60, or even if it is transmitted, the impact is reduced, so that the tubular member 61 is not easily damaged. Thereby, ink does not touch the inner wall of the ink introduction path 60, and the ink introduction path 60 can be further protected.

When the tubular member 61 is formed in the ink introduction path 60 by metal plating or the like, defects such as pinholes are likely to occur in the plating film, and the ink introduction path 60 may not be protected. In addition, the plating film is easily broken by impact. Therefore, it is preferable to provide the tubular member 61 separately and insert it into the ink introduction path 60 without performing plating as in this embodiment.

As mentioned above, although embodiment of this invention was described, this invention is not limited to what was mentioned above. In the embodiment described above, the tubular member 61 is provided by being inserted into the ink introduction path 60. However, the present invention is not limited to this, and the tubular member 61 may be formed by molding. That is, the tubular member 6
After molding 1 with metal, insert molding may be performed to mold the holder head 21 and the head case 22 on the outer peripheral side of the tubular member 61. Further, after the tubular member 61 is molded from a desired resin by two-color molding, the holder head 21 and the head case 22 are formed on the outer peripheral side thereof.
May be molded. After molding the holder head 21 and the head case 22 respectively,
A tubular member 61 may be provided by introducing and molding a resin having desired ink resistance into the ink introduction path 60. Even in the case of molding in this way, the ink introduction path 60 can be protected without generating pinholes such as a plating film.

  Further, the ink supply needle 12 may be made of the same material as that of the tubular member 61.

In the embodiment described above, the flexural vibration type piezoelectric element is exemplified as the pressure generating means for applying pressure to the liquid in the pressure generating chamber. However, the pressure generating means is not particularly limited, and for example, a piezoelectric material and an electrode forming material. May be a longitudinal vibration type piezoelectric element that is alternately stacked and expands and contracts in the axial direction, or a heating element or the like.

In the above-described embodiment, the present invention has been described by exemplifying an ink jet recording head main body and an ink jet recording apparatus that eject ink droplets. However, the present invention broadly includes a liquid ejecting head main body and a liquid ejecting apparatus including the same. It is intended for general use. Examples of the liquid ejecting head main body include a recording head main body used for an image recording apparatus such as a printer, a color material ejecting head main body used for manufacturing a color filter such as a liquid crystal display, an organic EL display, and an FED (field emission display). An electrode material ejection head main body used for electrode formation, a bioorganic matter ejection head main body used for biochip production, and the like can be given.

20 recording head body, 21 holder head, 22 head case, 23 pressure generating chamber, 24 first flow path forming substrate, 25 second flow path forming substrate, 26 third flow path forming substrate, 27 reservoir, 28 second 1 reservoir section, 29 ink supply path, 30 nozzle, 31 nozzle plate, 36 piezoelectric element, 39 second reservoir section, 40 third reservoir section, 44 opening section, 45 ink introduction port, 4
7 Lower ink introduction path, 50 fixing plate, 61 tubular member

Claims (5)

A liquid ejecting head body that ejects liquid droplets through a nozzle opening by causing pressure fluctuation in the pressure generating chamber by the pressure generating means, and supplying the liquid to the liquid ejecting head body fixed on the liquid ejecting head body A flow path member having a flow path to perform,
A liquid ejecting head, wherein a tubular member that covers the inner peripheral surface is provided on an inner peripheral surface of a flow channel formed inside the flow channel member. The liquid ejecting head according to claim 1, wherein the tubular member is provided by being inserted into the flow path. The liquid ejecting head according to claim 1, wherein the tubular member is formed and provided in the flow path by integral molding when the flow path is formed. The liquid ejecting head according to claim 1, wherein the tubular member is made of glass. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1.

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