JP2007160867A - Liquid-jet recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid-jet recording head which causes no poor printing such as non-delivery generated by getting an output port blocked with metal fiber which is a filter material, the fiber reaching the output port during printing. <P>SOLUTION: The liquid-jet recording head has a filter at a liquid introduction opening of an ink supply passage of the liquid-jet recording head and a liquid supply part of the ink tank composed of a presser of fiber abutting on the filter. For the filter provided at the liquid introduction opening abutting on the ink tank being upstream of the ink supply passage, a nonwoven filter of metal fiber is provided as the first filter. For the recording element substrate side downstream of the ink supply passage, a mesh filter is provided as the second filter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid discharge recording head.

  The liquid discharge recording apparatus is a so-called non-impact recording type recording apparatus, which is capable of high-speed recording and recording on various recording media, and has a feature that noise during recording hardly occurs. ing. For this reason, the liquid discharge recording apparatus is widely adopted as an apparatus that bears a recording mechanism such as a printer, a word processor, a facsimile machine, and a copying machine.

  As a typical example of the liquid discharge recording method used in this type of liquid discharge recording apparatus, there is a method using an electrothermal conversion element as a discharge energy generating element. In this method, recording liquid droplets are ejected from a minute ejection port to perform recording on a recording medium. In general, a recording head having ejection nozzles for forming droplets, and the recording head And a recording liquid supply system for supplying the recording liquid. In a liquid jet recording head using an electrothermal conversion element, an electrothermal conversion element is provided in a pressurizing chamber, and an electric pulse serving as a recording signal is applied to the electrothermal conversion element to give thermal energy to the recording liquid. The bubble pressure at the time of foaming (boiling) of the recording liquid caused by the phase change is used for ejecting recording droplets. Furthermore, there are two types of liquid jet recording heads that use the electrothermal conversion method: one that discharges the recording liquid in parallel to the substrate on which the electrothermal conversion elements are arranged (edge shooter), and the other that the electrothermal conversion elements are arranged. There is a system (side shooter) that discharges the recording liquid perpendicularly to the formed substrate. Recently, the liquid discharge recording head has been miniaturized, and the number of colors has been increased and the printing speed has been increased. For example, a single liquid discharge recording head can contain up to 8 colors including yellow, magenta, cyan, black, and other multiple colors. Products that discharge color recording liquid have been commercialized.

  Now, as a liquid discharge recording head used in the above-described liquid discharge recording apparatus, an ink tank for storing the supplied ink is separately formed with respect to a recording head having a function of discharging ink. An ink tank that is detachably attached to a recording head is known. Further, in this way, the recording head and the ink tank are detachable from each other, and the ink tank is loaded with a porous member for holding the supplied ink, and the ink tank It is conceivable that a filter is provided in the ink introduction part on the recording head side that is fitted to the ink supply part.

  In other words, by providing such a filter in the ink introduction part on the recording head side, anything that hinders the ejection of debris, dust, etc., from the porous member loaded in the ink tank side enters the recording head. In addition, it is possible to prevent dust from entering from the outside when the ink tank is detached.

  FIG. 2 shows a schematic cross-sectional shape of a conventional ink supply path and filter arrangement configuration.

  A pressure contact body 106 is provided in the ink supply portion of the ink tank H1900, while a filter 103 is provided in the liquid inlet of the ink supply member H1500. When ink is supplied, ink supply by contact between the filter 103 and the pressure contact body 106 is provided. The form is used conventionally.

  Conventionally, a non-woven fabric filter 103 made of metal fibers has been adopted as a filter for a liquid introduction portion that receives ink supplied from an ink tank.

  It is known that a method for producing a non-woven fabric filter using metal fibers is generally made by stretching a metal material as a material to a prescribed wire diameter of several μm units, forming a web, and then sintering and rolling. Since a very fine eye filter can be manufactured, it is a very advantageous filter for preventing entry of dust.

For example, Patent Document 1, Patent Document 2, and Patent Document 3 can be cited as conventional examples.
JP 2002-137410 A JP 2004-50625 A JP-A-6-238910

  However, the conventional liquid discharge recording head has the following problems.

  In recent years, liquid discharge recording heads are becoming more and more miniaturized with increasing number of inks and printing speed, and accordingly, the diameter of the discharge port for discharging the ink of the recording element has been reduced. It is being advanced. For this reason, as one of the future concerns, it is conceivable that the print quality is deteriorated due to clogging of dust, foreign matter, or the like at the ink discharge port.

  However, in the case of a nonwoven fabric filter that has been conventionally employed, since there is no weaving of metal fibers, it is weak against external impact and lacks flexibility, so that the metal fibers tend to fray.

  Therefore, in the liquid discharge recording head, there is a problem that metal fibers are lost due to the ink flow in the ink supply path from the ink tank to the recording element for discharging ink. Especially when sucking out the thickened ink at the discharge port, when the recording head sucks and recovers, the ink flows at a higher speed than normal printing. Reaching the ejection port of the head and clogging the ejection port causes printing defects such as non-ejection of ink, leading to degradation of printing quality.

  Therefore, the object of the present invention is to focus on the problems to be solved as described above, and to prevent the print quality from being damaged by the missing metal fiber which is the material of the conventional nonwoven fabric filter, and adversely affect the printing. It is an object of the present invention to provide a liquid discharge recording head free from any problem.

  Liquid discharge recording in which an ink supply path is formed between a recording element substrate for receiving ink supplied from one or a plurality of ink tanks mounted on the carriage and discharging ink provided in the recording element unit A liquid discharge recording head in which a liquid supply port of an ink supply path of the liquid discharge recording head has a filter, and the ink tank includes a pressure contact member made of a fiber contacting the filter. In the head, a non-woven fabric filter made of a metal fiber is provided as a first filter in a filter provided in a liquid inlet that contacts an ink tank on the upstream side of the ink supply path, and a second side is provided on the recording element substrate side on the downstream side. The above object is achieved by providing a mesh filter as the filter.

  According to the present invention, even when the metal fiber that is the material of the nonwoven fabric filter that is the first filter is lost due to the flow of the ink and flows into the ink flow path, the mesh filter that is the second filter ensures the metal fiber. It becomes possible to capture.

  As described above, during printing, the reliability of the liquid ejection recording head is improved and the recording quality is improved without causing printing defects such as non-ejection caused by the metal fibers reaching the ejection port and clogging the ejection port. Can be made.

(Example 1)
Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIGS. 3 to 8 are explanatory diagrams for explaining each of the preferred head cartridge, recording head, and ink tank and the relationship thereof to which the present invention is implemented or applied.

  As can be seen from FIGS. 3 and 4, the recording head H1001 is a constituent element of the recording head cartridge H1000. The recording head cartridge H1000 is an ink tank that is detachably provided on the recording head H1001 and the recording head H1001. H1900 (H1901, H1902, H1903, H1904).

  The recording head cartridge H1000 is fixedly supported by positioning means and electrical contacts of a carriage (not shown) mounted on the ink jet recording apparatus main body, and is detachable from the carriage. The ink tank H1901 is for black ink, the ink tank H1902 is for cyan ink, the ink tank H1903 is for magenta ink, and the ink tank H1904 is for yellow ink. In this way, each of the ink tanks H1901, H1902, H1903, and H1904 is detachable from the recording head H1001, and each ink tank can be replaced, so that the running cost of image recording by the ink jet recording apparatus is reduced. Reduced.

  Next, the recording head H1001 will be described in more detail in order for each component constituting the recording head.

<1> Recording Head The recording head H1001 is a bubble jet (registered trademark) side that performs recording using an electrothermal transducer that generates thermal energy for causing film boiling to occur in ink in response to an electrical signal. This is a recording head that is of a shooter type.

  As shown in the exploded perspective view of FIG. 5, the recording head H1001 includes a recording element unit H1002, an ink supply unit H1003, and a tank holder H2000.

  Further, as shown in the exploded perspective view of FIG. 6, the recording element unit H1002 includes a first recording element substrate H1100, a second recording element substrate H1101, a first plate H1200, an electrical wiring tape H1300, and an electrical contact substrate H2200. The ink supply unit H1003 is composed of an ink supply member H1500, a flow path forming member H1600, a joint rubber H2300, a filter H1700, and a seal rubber H1800.

<1-1> Recording Element Unit FIG. 7 is a perspective view showing the configuration of the first recording element substrate H1100 in a partially exploded state.

  The first recording element substrate H1100 is anisotropically etched using, for example, a Si substrate H1110 having a thickness of 0.5 to 1 mm and an ink supply port H1102 having a long groove-like through-hole as an ink channel using the crystal orientation of Si. The electrothermal conversion elements H1103, which are formed by a method such as sand blasting, are arranged in a zigzag pattern on each side of the ink supply port H1102, and the recording elements are arranged in a staggered pattern. An electric wiring such as Al for supplying power to H1103 is formed by a film forming technique. Furthermore, electrode portions H1104 for supplying electric power to the electric wiring are arranged on both outer sides of the electrothermal transducer H1103, and bumps H1105 such as Au are formed on the electrode portion H1104. On the Si substrate, an ink channel wall H1106 and an ejection port H1107 for forming an ink channel corresponding to the electrothermal conversion element H1103 are formed of a resin material by a photolithography technique, and an ejection port array H1108 is formed. Forming. Accordingly, since the ejection port is provided to face the electrothermal conversion element H1103, the ink supplied from the ink flow path H1102 is ejected by bubbles generated by the electrothermal conversion element H1103.

  FIG. 8 is a perspective view showing the second recording element substrate H1101 in a partially exploded state.

  The second recording element substrate H1101 is a recording element substrate for ejecting ink of three colors, and has three ink supply ports H1102 formed in parallel, and electric is provided on both sides of each ink supply port. A heat conversion element and an ink discharge port are formed. Of course, like the first recording element substrate H1100, an ink supply port, an electrothermal conversion element, an electric wiring, an electrode portion, and the like are formed on the Si substrate, and an ink flow path and an ink discharge are made of a resin material on the Si substrate by a photolithography technique. An exit is formed.

  Similarly to the first recording element substrate, a bump H1105 such as Au is formed on the electrode portion H1104 for supplying electric power to the electric wiring.

  Reference is again made to FIG. The first plate H1200 is made of, for example, an alumina (Al2O3) material having a thickness of 0.5 to 10 mm. The material of the first plate is not limited to alumina, and has a linear expansion coefficient equivalent to that of the material of the recording element substrate H1100 and is equivalent to the thermal conductivity of the material of the recording element substrate H1100. Alternatively, it may be made of a material having an equivalent or higher thermal conductivity. The material of the first plate H1200 is, for example, any of silicon (Si), aluminum nitride (AlN), zirconia, silicon nitride (Si3N4), silicon carbide (SiC), molybdenum (Mo), and tungsten (W). May be. The first plate H1200 has ink supply ports H1201 for supplying black ink to the first recording element substrate H1100 and inks for supplying cyan, magenta, and yellow ink to the second recording element substrate H1101. A supply port H1201 is formed, the ink supply port 1102 of the recording element substrate corresponds to the ink supply port H1201 of the first plate H1200, and the first recording element substrate H1100 and the second recording element substrate H1101. Are bonded and fixed to the first plate H1200 with high positional accuracy. The first adhesive H1202 used for bonding is desirably a low viscosity, low curing temperature, cured in a short time, has a relatively high hardness after curing, and has ink resistance. The first adhesive H1202 is, for example, a thermosetting adhesive mainly composed of an epoxy resin, and the thickness of the adhesive layer is desirably 50 μm or less.

  The electrical wiring tape H1300 applies an electrical signal for ejecting ink to the first recording element substrate H1100 and the second recording element substrate H1101, and includes a plurality of recording element substrates. An electrical contact substrate having an opening portion, an electrode terminal H1302 corresponding to the electrode portion H1104 of each recording element substrate, and an external signal input terminal H1301 located at the end of the wiring tape for receiving an electrical signal from the main unit An electrode terminal portion H1303 for electrical connection with H2200 is provided, and the electrode terminal H1302 and the electrode terminal 1303 are connected by a continuous copper foil wiring pattern.

  The electrical wiring tape H1300, the first recording element substrate 1100, and the second recording element substrate H1101 are electrically connected to each other, and the connection method is, for example, the electrode portion 1104 of the recording element substrate and the electrical wiring tape H1300. The electrode terminal H1302 is electrically bonded by a thermal ultrasonic pressure bonding method.

  The second plate H1400 is a single plate-like member having a thickness of 0.5 to 1 mm, for example, and is formed of a ceramic material such as alumina (Al2O3) or a metal material such as Al or SUS. The first recording element substrate H1100 and the second recording element substrate H1101 that are bonded and fixed to the first plate H1200 have openings that are larger than the outer dimensions thereof. Further, the first recording element substrate H1100 and the second recording element substrate H1101 and the electric wiring tape H1300 are bonded to the first plate H1200 with a second adhesive H1203 so as to be electrically connected in a plane. The back surface of the wiring tape H1300 is bonded and fixed with a third adhesive H1306.

  Electrical connection portions of the first recording element substrate H1100 and the second recording element substrate H1101 and the electric wiring tape H1300 are sealed with a first sealant H1307 (not shown) and a second sealant H1308, Protects electrical connections from ink corrosion and external impacts. The first sealing agent mainly seals the back surface side of the connection portion between the electrode terminal H1302 of the electric wiring tape and the electrode portion H1105 of the recording element substrate and the outer peripheral portion of the recording element substrate, and the second sealing agent. Seals the front side of the connecting part.

  Further, an electrical contact substrate H2200 having an external signal input terminal H1301 for receiving an electrical signal from the main unit is connected to the end of the electrical wiring tape by thermocompression bonding using an anisotropic conductive film or the like.

  The electric wiring tape H1300 is bent at one side surface of the first plate H1200, and is bonded to the side surface of the first plate H1200 with the third adhesive H1306. As the third adhesive H1306, for example, a thermosetting adhesive having a thickness of 10 to 100 μm mainly composed of an epoxy resin is used.

<1-2> Ink Supply Unit The ink supply member H1500 is formed by resin molding, for example. As the resin material, it is desirable to use a resin material mixed with 5 to 40% of glass filler in order to improve the shape rigidity.

  As shown in FIG. 9, the ink supply member H1500 is a component of the ink supply unit H1003 for guiding ink from the ink tank H1900 to the recording element unit H1002, and by ultrasonically welding the flow path forming member H1600. An ink flow path H1501 is formed. In addition, a filter H1700 for preventing entry of dust from the outside is joined to the joint H1517 engaged with the ink tank H1900 by welding. Further, in order to prevent ink from evaporating from the joint H1517 portion, A seal rubber H1800 is attached.

  The ink supply member H1500 also has a part of the function of holding the removable ink tank H1900, and has a first hole H1503 for engaging the second claw H1910 of the ink tank H1900.

  Further, as shown in FIG. 6, a mounting guide H1601 for guiding the recording head cartridge H1000 to the mounting position on the carriage of the ink jet recording apparatus main body, and an engaging portion for mounting and fixing the recording head cartridge to the carriage by a head set lever. H1508, an abutting portion H1509 in the X direction (carriage scanning direction) for positioning at a predetermined mounting position of the carriage, an abutting portion H1510 in the Y direction (recording medium conveyance direction), an abutting in the Z direction (ink ejection direction) A contact portion H1511 is provided. In addition, a terminal fixing portion H1512 for positioning and fixing the electrical contact substrate H2200 of the recording element unit H1002 is provided, and a plurality of ribs are provided around the terminal fixing portion H1512 to increase the rigidity of the surface having the terminal fixing portion H1512. ing.

<1-3> Coupling of Recording Head Unit and Ink Supply Unit As shown in FIG. 5, the recording head H1001 is completed by connecting the recording element unit H1002 to the ink supply unit H1003 and further to the tank holder H2000. The coupling is performed as follows.

  The ink supply port of the recording element unit H1002 (ink supply port H1201 of the first plate H1200) and the ink supply port of the ink supply unit H1003 (ink supply port H1601 of the flow path forming member H1600) are communicated so that ink does not leak. Therefore, each member is fixed with the screw H2400 so as to be pressure-bonded via the joint rubber H2300. At the same time, the recording element unit H1002 is accurately positioned and fixed with respect to the reference positions in the X, Y, and Z directions of the ink supply unit.

  The electrical contact substrate H1301 of the recording element unit H1002 is positioned and fixed to one side surface of the ink supply member H1500 by terminal positioning pins H1515 (2 places) and terminal positioning holes H1309 (2 places). The fixing method is, for example, fixing by crimping the terminal coupling pin H1515 provided on the ink supply member H1500, but may be fixed using other fixing means. A completed drawing is shown in FIG.

  Further, the recording head H1001 is completed by fitting the coupling hole and coupling portion of the ink supply member H1500 with the tank holder into the tank holder H2000 and coupling them. The completed drawing is shown in FIG.

<2> Recording Head Cartridge FIGS. 3 and 4 are diagrams for explaining mounting of the recording head H1001 and the ink tanks H1901, H1902, H1903, and H1904 constituting the recording head cartridge H1000, and the ink tanks H1901, H1902, H1903, Corresponding color ink is stored inside the H1904. Further, as shown in FIG. 9, each ink tank is formed with an ink supply port H1907 for supplying ink in the ink tank to the recording head H1001. For example, when the ink tank 1901H is attached to the recording head H1001, the ink supply port H1907 of the ink tank H1901 is brought into pressure contact with the filter H1700 provided in the joint portion H1520 of the recording head H1001, and the black ink in the ink tank H1901 is supplied with ink. The ink is supplied from the port H1907 to the first recording element substrate through the first plate H1200 through the ink flow path H1501 of the recording head H1001.

  Then, ink is supplied to the foaming chamber having the electrothermal conversion element H1103 and the discharge port H1107, and is ejected toward a recording sheet as a recording medium by the thermal energy given to the electrothermal conversion element H1103.

  FIG. 1 is a sectional view schematically showing Embodiment 1 of an ink supply path and filter arrangement configuration according to the present invention.

  Unlike the conventional example shown in FIG. 2, this example uses a non-woven fabric filter in contact with the ink tank as a first filter in the ink supply path, and further captures a metal fiber missing from the non-woven fabric filter. The liquid discharge recording head is configured by using a mesh filter as a filter.

  The non-woven fabric filter 103 as the first filter is fixed to the liquid introducing portion 101 of the ink supply member H1500 with high positional accuracy as usual.

  The mesh filter 104 as the second filter is provided between the flow path forming member H1600 for supplying ink from the ink supply member H1500 to the recording element substrates H1100 and H1101.

  For fixing the mesh filter 104, an ultrasonic welding process for assembling the ink supply member H1500 and the flow path forming member H1600 is used to couple the mesh filter 104 between the ink supply member H1500 and the flow path forming member H1600, that is, the weld surface 105. Is done.

  With the liquid discharge recording head having the ink supply path 102 according to the above embodiment, the metal fiber missing from the nonwoven fabric filter 103, which was a problem, can be reliably captured by the mesh filter 104, and the print quality is deteriorated. Can be avoided, and the reliability of the liquid discharge recording head can be improved.

(Example 2)
FIG. 12 is a cross-sectional view schematically showing Example 2 of the ink supply path and filter arrangement configuration according to the present invention.

  The basic configuration of the liquid discharge recording head of the second embodiment is substantially the same as that of the first embodiment except for the configuration of the ink supply path 102 and the filters 103 and 104 provided in the ink supply path.

  Example 2 has a configuration in which a mesh filter 104 that captures the lack of metal fibers generated by the nonwoven fabric filter 103, which is a problem, is stacked. The aim is not only to capture the lack of metal fibers, but also the nonwoven fabric filter that is the first filter. It is also intended to reinforce the strength to prevent filter deformation due to insufficient filter strength when the wire diameter becomes thinner.

  In the case of Example 2, it is comprised with the double filter 107 which sintered the mesh filter 104 which is a 2nd filter with respect to the nonwoven fabric filter 103 which is a 1st filter. Regarding the fixing of the double filter 107, the ink supply member H1500 and the flow path forming member H1600 are first coupled by ultrasonic welding, and in this state, positional accuracy is obtained by thermal welding to the liquid introducing portion 101 of the ink supply member H1500. It is fixed well.

  If the liquid discharge recording head has the ink supply path 102 according to the above embodiment, the metal fiber missing from the nonwoven fabric filter 103 which has been a problem can be reliably captured by the mesh filter 104 sintered to the nonwoven fabric filter. In addition, since the strength of the filter itself can be increased, it is possible to prevent the deterioration of the print quality and the deformation of the filter, and to improve the reliability of the liquid discharge recording head.

FIG. 3 is a schematic cross-sectional view illustrating an ink supply path and a filter arrangement configuration according to the first embodiment of the present invention. It is typical sectional drawing which shows the conventional ink supply path and filter arrangement configuration. FIG. 3 is a perspective view showing a state in which the recording head and the ink tank are combined in an embodiment of the recording head cartridge of the present invention. FIG. 2 is a diagram illustrating an embodiment of a recording head cartridge according to the present invention in a state where a recording head and an ink tank are separated. FIG. 4 is an exploded perspective view of the recording head cartridge shown in FIG. 3 and the like. FIG. 6 is an exploded perspective view of the ink supply unit and the recording element unit shown in FIG. 5. FIG. 7 is a perspective view in which a part of the first recording element substrate shown in FIG. 6 is broken. FIG. 7 is a perspective view in which a part of the second recording element substrate shown in FIG. 6 is cut away. FIG. 4 is a cross-sectional view of the recording head cartridge shown in FIG. 3 and the like. FIG. 4 is a perspective view showing a combined body of a recording element unit and an ink supply unit in the recording head cartridge shown in FIG. 3 and the like. FIG. 4 is a perspective view illustrating a bottom surface of the recording head cartridge illustrated in FIG. 3 and the like. It is typical sectional drawing which shows the ink supply path and filter arrangement | positioning structure of 2nd Example form of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Liquid introduction part 102 Ink supply path 103 Nonwoven fabric filter 104 Mesh filter 105 Welding surface 106 Pressure contact body 107 Double filter H1000 Recording head cartridge H1001 Recording head H1002 Recording element unit H1003 Ink supply unit H1100 1st recording element substrate H1101 2nd Recording element substrate H1102 Ink supply port H1103 Electrothermal conversion element H1104 Electrode H1105 Bump H1106 Ink channel wall H1107 Discharge port H1108 Discharge port array H1110 Si substrate H1200 First plate H1201 Ink supply port H1300 Electrical wiring tape H1301 External signal input terminal H1302 Electrode terminal H1303 Electrode terminal portion H1307 First sealant H1308 Second sealant H1309 End Positioning hole H1310 Terminal coupling hole H1400 Second plate H1500 Ink supply member H1501 Ink flow path H1502 Tank positioning hole H1503 First hole H1504 Second hole H1509 X abutting part H1510 Y abutting part H1511 Z abutting part H1512 terminal Fixed part H1515 Terminal positioning pin H1516 Terminal coupling pin H1520 Joint part H1600 Flow path forming member H1601 Mounting guide H1602 Ink supply port H1700 Filter H1800 Seal rubber H1900 Ink tank H1901 Black ink tank H1902 Cyan ink tank H1903 Magenta ink tank H1904 Yellow ink tank H1907 Ink Supply port H1908 Tank positioning pin H1909 First claw 1910 second pawl H1911 third pawl H1912 movable lever H2000 tank holder H2300 joint rubber H2400 bis

Claims (1)

  Liquid discharge recording in which an ink supply path is formed between a recording element substrate for receiving ink supplied from one or a plurality of ink tanks mounted on the carriage and discharging ink provided in the recording element unit A liquid discharge recording head in which a liquid supply port of an ink supply path of the liquid discharge recording head has a filter, and the ink tank includes a pressure contact member made of a fiber contacting the filter. In the head, the filter provided in the liquid inlet that contacts the ink tank on the upstream side of the ink supply path is provided with a non-woven fabric filter made of metal fibers as the first filter, and the second side toward the recording element substrate on the downstream side. A liquid discharge recording head comprising a filter and a metal fiber braided mesh filter.

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