JP4208000B2 - Inkjet printer head - Google Patents

Description

  The present invention relates to an inkjet head used in an inkjet printer. In order to enable high-definition printing, recent ink jet printers have been required to have a small and lightweight configuration in which ink flow paths can move independently. The present invention is an improvement of an ink jet head in which the pressure in the ink flow path is variable by a piezoelectric element.

  FIG. 9 is a perspective view schematically showing the ink jet printer. The ink jet printer 1 includes a platen roller 2 for feeding the recording medium 3, two stay shafts 4a and 4b parallel to the platen roller 2, and stay shafts 4a and 4b. A carriage 5 that is guided and reciprocates in the length direction of the platen roller 2, and an inkjet head unit 6 mounted on the carriage 5. The inkjet head unit replenishes ink to be ejected from the inkjet head unit 6 to the recording medium 3. 6 and the ink reservoir 7 are connected by a flexible tube 8.

In such an ink jet printer 1, as a means for causing ink to fly from the ink jet head unit 6, a bubble jet (registered trademark) that utilizes a change in volume when energizing a heating element embedded in a nozzle and generating bubbles in the ink is used. ) Method and an impact method using a pressure wave generated by energizing a piezoelectric element are attracting attention.

  As an impact type piezoelectric inkjet head, (1) an ink flow channel groove is formed on the surface of a piezoelectric body incorporating a piezoelectric drive electrode, and the groove is closed with an upper lid made of glass, and (2) a piezoelectric drive electrode. (3) A piezoelectric drive on the upper and lower surfaces of the flow path plate formed with a vertically penetrating groove. A material in which a piezoelectric body containing an electrode is attached is generally known.

  10 is an exploded schematic view of a flow path plate type piezoelectric ink jet head, FIG. 11 is a sectional view of the piezoelectric ink jet head shown in FIG. 10, FIG. 12 is an explanatory diagram of interference in the piezoelectric ink jet head, and FIG. It is explanatory drawing of an interference prevention type piezoelectric inkjet head.

  In FIG. 10, an ink jet head 9 incorporated in an ink jet head unit 6 joins a piezoelectric substrate 10 and an ink flow path plate 11 having a plurality (four in the figure) of ink flow path grooves 12, and a plurality of ink flow path plates 11 on the front surface. A nozzle plate 14 formed with a plurality of (four in the figure) nozzles 13 communicating with the ink flow channel groove 12 is joined, and the ink flow channel groove 12 communicates with the ink supply port 15 through an ink supply channel (not shown). One end of the flexible tube 8 (see FIG. 9) is connected to the ink supply port 15.

  In FIG. 11, piezoelectric drive electrodes 16 are formed on the piezoelectric substrate 10 so as to correspond to the ink flow path grooves 12 of the ink flow path plate 11. When a predetermined voltage is applied between the electrodes, the piezoelectric driving electrode 16 composed of two or more layers (three layers in the figure) extends in the upward direction in the figure and compresses the ink flow channel groove 12. Part of the ink in the ink flow path groove 12 flies from the nozzle 13 toward the recording medium 3 (see FIG. 9).

  In the inkjet head 9 of the method (1) in which a plurality of piezoelectric drive electrodes 16 and a plurality of ink flow path grooves 12 corresponding to the electrodes 16 are formed, the piezoelectric drive electrodes 16 and the ink flow path grooves are used for fine printing. 12 need to be close.

Therefore, when a driving voltage is applied to a predetermined driving electrode 16, for example, the second driving electrode 16 from the left in the inkjet head 9 of FIG. 12, the piezoelectric substrate 10 applies a driving voltage as indicated by a broken line 17 in FIG. 12. portion is extends upward, the volume of the predetermined ink flow path groove 12 _-1 is narrowed, so that is compressed slightly even the volume of the ink passage grooves 12 _-2 adjacent.

  The compression of the adjacent ink flow path groove 12-2 is generally called interference. As a method for eliminating crosstalk due to the interference, as shown in FIG. 13, a slit 18 is provided between the adjacent ink flow path grooves 12 as shown in FIG. 10 is known. The slit 18 having a width of 10 to 80 μm is generally mechanically cut with a dicing saw.

Generally, the piezoelectric substrate 10 and the ink flow path plate 11 are joined by [1] laminating a film of a photocurable adhesive called a dry film on the surface of the piezoelectric substrate 10 or applying a liquid photocurable adhesive. [2] The dry film or adhesive film is irradiated with an ultraviolet ray having a predetermined strength, for example, about 100 mj / cm ² and cured to form an adhesive layer, and [3] ink is applied to the adhesive layer. The flow path plates 11 are stacked and thermocompression bonded at a pressure of about 500 KPa at 150 ° C. for about 1 hour.

In addition, in the impact-type piezoelectric inkjet head capable of higher definition than the bubble jet (registered trademark) method, in addition to the method in which the ink channel groove is formed in the ink channel plate, the piezoelectric substrate in which the piezoelectric drive electrode is formed In some cases, an ink flow path groove is formed on the surface of the ink flow path plate, and a piezoelectric substrate on which a piezoelectric drive electrode is formed is bonded to both surfaces of an ink flow path plate formed with a groove penetrating vertically.

FIG. 14 is an explanatory diagram of a green sheet used for a conventional piezoelectric substrate, and FIG. 15 is an explanatory diagram of a conventional piezoelectric substrate having a built-in drive electrode. 14, for the production of conventional piezoelectric substrate 10, a green sheet 10 _-1 consisting piezoelectric powder, more on the surface of the green sheet 10 _-1 (figure 4) to form a drive electrode pattern 16 _-1 a green sheet _10-2, using a green sheet 10 _-3 forming the drive electrode pattern 16 _-2 on the surface of the green sheet 10 _-1.

The green sheet 10 _-1 is prepared from a slurry containing piezoelectric powder by a doctor blade method, and the plurality of drive electrode patterns 16 _-1 of the green sheet 10 _-2 are ink from the middle part to one end part (front end part). While formed at a pitch corresponding to the ink flow channel groove of the flow channel plate, the intermediate portion and the other end portion (rear end portion) are formed at an appropriate interval.

Drive electrode pattern 16 of the green sheet 10 _{-3 -2} has one end from the intermediate portion to the (front end portion) is formed so wide corresponding to the plurality of drive electrode patterns 16 _-1, the other end portion from the intermediate portion until (rear end) is formed away at appropriate intervals from the other end of the drive electrode pattern 16 _-1.

In FIG. 15A, the piezoelectric substrate 10 has a plurality of (eight in the figure) green sheets 10 _-1 stacked thereon, and a plurality of green sheets 10 _-3 and 10 _-2 alternately _disposed thereon (the figure shows four). And a plurality of (two in the figure) green sheets _10-1 stacked thereon are fired.

Therefore, the end of the drive electrode pattern 16 _-1 at the front end surface of the piezoelectric substrate 10, as shown in FIG. 15 (a), while aligning a narrow pitch corresponding to the ink flow path grooves of the ink flow path plate, On the rear end face of the piezoelectric substrate 10, as shown in FIG. 15B, the end portions of the drive electrode patterns _16-1 and _16-2 have the same order, for example, the drive electrodes in the same order from the right side in the green sheet _10-2 in FIG. the rear end portion of the pattern 16 _-1 aligned vertically, the rear end portion of the order of different drive electrode pattern 16 _-1 exposed away in the left-right direction, respectively.

Therefore, as shown in FIG. 15C, the exposed ends of the drive electrode patterns 16 _-1 and 16 _-2 aligned in the vertical direction on the rear end face of the piezoelectric substrate 10 are connected by conductive terminals 19 _{-1 to} 19 _-5 . The piezoelectric substrate 10 is completed.

The piezoelectric substrate 10 is cut after firing a large substrate from which a plurality of piezoelectric substrates 10 can be obtained, and then, generally, the conductive terminals 19 _{-1 to} 19 _-5 are formed using printing means. .

That is, in the conventional piezoelectric substrate 10 for conductive terminals 19 _-1 to 19 _-5 formation, driving electrode pattern 16 _-1 and 16 _-2, it is necessary to separate at the rear surface of the piezoelectric substrate 10.

  As described above, when a plurality of piezoelectric drive electrodes are formed on the same piezoelectric element substrate, crosstalk occurs when the ink flow path and the piezoelectric drive electrode are brought close to each other, and the crosstalk is suppressed and the flow path plate system is practically used. Had become a major obstacle for.

  And the conventional method of eliminating crosstalk is a configuration in which slits are formed between adjacent piezoelectric drive electrodes, and the slit by machining takes a long time to form, and positioning to determine the slit formation position is troublesome, There was a problem that it was not suitable for mass production.

  Furthermore, the conventional piezoelectric substrate is increased in size from the need to separate the electrode end that connects the piezoelectric drive electrode to the drive circuit, and the conventional configuration in which an ink flow path plate or lid plate made of glass or the like is joined to the piezoelectric substrate has the number of parts. However, there is a problem that the cost increases and the size is difficult to reduce.

  An object of the present invention is to make an ink flow path accessible without obstruction due to crosstalk, and to reduce the size of an inkjet printer head at low cost.

In order to achieve the above object, the present invention has an upper surface of a second piezoelectric substrate bonded to a lower surface of a first piezoelectric substrate in which an ink flow path groove is formed. A first piezoelectric drive electrode corresponding to the bottom surface of the ink flow path groove, and a direction located at a side of the ink flow path groove to suppress deformation of the second piezoelectric substrate by at least the second piezoelectric drive electrode A third piezoelectric drive electrode that is deformed is formed, and the second piezoelectric drive electrode corresponding to the ink flow path groove is formed in the second piezoelectric substrate, and the upper and lower sides sandwich the ink flow path groove. The first piezoelectric substrate and the second piezoelectric substrate are deformed by applying a voltage to the first piezoelectric drive electrode and the second piezoelectric drive electrode located at the position, and the ink flow path groove is compressed in the vertical direction. As a result, from the nozzle communicating with the compressed ink flow path groove Ink jet printer head in which the ink flies, wherein the first piezoelectric substrate includes a plurality of first green sheets made of piezoelectric powder, and the first piezoelectric driving electrode on a predetermined portion of the first green sheet. A plurality of second green sheets on which the electrode patterns are formed, and notches serving as the ink flow channel grooves and electrode patterns of the third piezoelectric drive electrodes are formed in predetermined portions of the first green sheets. The plurality of third green sheets are integrated by a baking process, and the second piezoelectric substrate has a plurality of the first green sheets and a predetermined number of the first green sheets. An ink jet comprising: a plurality of fourth green sheets each having an electrode pattern of the second piezoelectric driving electrode formed in a part thereof integrated by a baking process. To provide a printer head.
In the present invention, a plurality of the first piezoelectric substrates having the ink flow channel grooves formed on the upper surface are stacked and joined, whereby a plurality of the ink flow channel grooves are arranged in the stacked direction, and the uppermost first A second piezoelectric substrate is bonded to the upper surface of the first piezoelectric substrate, and in each of the first piezoelectric substrates, a first corresponding to the bottom surface of the ink flow channel groove formed in the first piezoelectric substrate. The piezoelectric driving electrode, the second piezoelectric driving electrode corresponding to the ink flow path groove of the other first piezoelectric substrate stacked below the first piezoelectric substrate, and the first piezoelectric driving electrode corresponding to the bottom surface. A third piezoelectric drive that is located on the side of the ink flow path groove where the piezoelectric drive electrode is formed and deforms in a direction that suppresses deformation of the second piezoelectric substrate by at least the second piezoelectric drive electrode. An electrode is formed in the second piezoelectric substrate, A second piezoelectric drive electrode corresponding to the ink flow path groove of the first piezoelectric substrate is formed, and the first piezoelectric drive electrode and the second piezoelectric drive electrode positioned above and below the ink flow path groove As a result of deforming the first piezoelectric substrate and the second piezoelectric substrate by applying a voltage to the ink channel groove and compressing the ink flow channel groove in the vertical direction, ink is ejected from the nozzle communicating with the compressed ink flow channel groove. The first piezoelectric substrate is a plurality of first green sheets made of piezoelectric powder, and a cut portion that becomes the ink flow channel groove in a predetermined portion of the first green sheet. A plurality of second green sheets each having a notch and an electrode pattern of the third piezoelectric drive electrode formed thereon, and an electrode pattern of the first piezoelectric drive electrode formed on a predetermined portion of the first green sheet A plurality of third green sheets and a plurality of fourth green sheets in which an electrode pattern of the second piezoelectric driving electrode is formed on a predetermined portion of the first green sheet. The second piezoelectric substrate is integrated by a baking process in which a plurality of the first green sheets and a plurality of the fourth green sheets are stacked, An ink jet printer head is provided.
Furthermore, the first inkjet printer head of the present invention that achieves the above object is characterized in that the upper surface of the second piezoelectric substrate is bonded to the lower surface of the first piezoelectric substrate in which the ink flow path grooves are formed. A first piezoelectric drive electrode corresponding to the bottom surface of the ink flow path groove is formed in the piezoelectric substrate, and a second piezoelectric drive electrode corresponding to the ink flow path groove is formed in the second piezoelectric substrate. The first piezoelectric substrate includes a plurality of first green sheets made of piezoelectric powder, and an electrode of the first piezoelectric drive electrode on a predetermined portion of the first green sheet. A baking process in which a plurality of second green sheets on which a pattern is formed and a plurality of third green sheets in which notches serving as ink flow channel grooves are formed in predetermined portions of the first green sheets are stacked. Integrated with the A plurality of first green sheets and a plurality of fourth green sheets each having an electrode pattern of the second piezoelectric driving electrode formed on a predetermined portion of the first green sheets. These are integrated by repeated baking processes.

  The second ink jet printer head of the present invention that achieves the above object is characterized in that the upper surface of the second piezoelectric substrate is bonded to the lower surface of the first piezoelectric substrate in which the ink flow path grooves are formed. A first piezoelectric drive electrode corresponding to the bottom surface of the ink flow path groove and a third piezoelectric drive electrode positioned on the side of the ink flow path groove are formed in the second piezoelectric substrate. Is a jet printer head in which a second piezoelectric drive electrode corresponding to the ink flow path groove is formed, wherein the first piezoelectric substrate includes a plurality of first green sheets made of piezoelectric powder, A plurality of second green sheets in which an electrode pattern of the first piezoelectric drive electrode is formed in a predetermined portion of the first green sheet; and the ink flow path groove in a predetermined portion of the first green sheet; Notch and electrode pattern of the third piezoelectric drive electrode A plurality of formed third green sheets are integrated by an overlapping baking process, and the second piezoelectric substrate includes a plurality of the first green sheets and the first green sheets. A plurality of fourth green sheets each having an electrode pattern of the second piezoelectric driving electrode formed on a predetermined portion of the first and second green sheets are integrated by baking.

  The third ink jet printer head of the present invention that achieves the above object stacks and joins a plurality of first piezoelectric substrates having ink channel grooves formed on the upper surface, and the upper surface of the uppermost first piezoelectric substrate. A second piezoelectric substrate is bonded to the first piezoelectric substrate, and a first piezoelectric drive electrode corresponding to the bottom surface of the ink flow channel groove and an ink flow channel of the lower first piezoelectric substrate are provided in the first piezoelectric substrate. A second piezoelectric drive electrode corresponding to the groove is formed, and a second piezoelectric drive electrode corresponding to the ink flow path groove of the uppermost first piezoelectric substrate is formed in the second piezoelectric substrate. In the inkjet printer head, the first piezoelectric substrate includes a plurality of first green sheets made of piezoelectric powder, and a notch serving as the ink flow channel groove in a predetermined portion of the first green sheet. The plurality of formed second green sheets and the first green A plurality of third green sheets in which an electrode pattern of the first piezoelectric drive electrode is formed in a predetermined portion of the sheet, and an electrode pattern of the second piezoelectric drive electrode in a predetermined portion of the first green sheet A plurality of the formed fourth green sheets are integrated by an overlapping baking process, and the second piezoelectric substrate includes a plurality of the first green sheets and a plurality of the fourth green sheets. The green sheets are integrated by baking treatment.

  A fourth ink jet printer head of the present invention that achieves the above object stacks and joins a plurality of first piezoelectric substrates having ink channel grooves formed on the upper surface, and the upper surface of the uppermost first piezoelectric substrate. A second piezoelectric substrate is bonded to the first piezoelectric substrate, and a first piezoelectric drive electrode corresponding to the bottom surface of the ink flow channel groove and an ink flow channel of the lower first piezoelectric substrate are provided in the first piezoelectric substrate. A second piezoelectric drive electrode corresponding to the groove and a third piezoelectric drive electrode positioned on the side of the ink flow path groove are formed, and the uppermost first electrode is formed in the second piezoelectric substrate. An inkjet printer head having a second piezoelectric drive electrode corresponding to the ink flow path groove of the piezoelectric substrate, wherein the first piezoelectric substrate includes a plurality of first green sheets made of piezoelectric powder; A notch serving as the ink flow path groove in a predetermined portion of the first green sheet And a plurality of second green sheets on which the electrode pattern of the third piezoelectric drive electrode is formed, and a plurality of electrodes on which the electrode pattern of the first piezoelectric drive electrode is formed on a predetermined portion of the first green sheet. A plurality of third green sheets and a plurality of fourth green sheets each having an electrode pattern of the second piezoelectric driving electrode formed on a predetermined portion of the first green sheet are integrated by a baking process. The second piezoelectric substrate is formed by integrating a plurality of the first green sheets and a plurality of the fourth green sheets by a baking process.

  The fifth ink jet printer head of the present invention that achieves the above object is that a baking means is used for joining the piezoelectric substrates in the first to fourth ink jet printer heads of the present invention.

  The method for manufacturing a piezoelectric substrate according to the present invention that achieves the above object is the method of manufacturing a piezoelectric substrate having a piezoelectric drive electrode therein, wherein at least one first through hole made of piezoelectric powder and formed in a predetermined portion is formed. A plurality of second through holes made of piezoelectric powder and communicating with each of the first through holes and an electrode of the piezoelectric drive electrode A fired body integrated by a firing process in which a plurality of second green sheets on which a pattern is formed are stacked and the second green sheets are stacked on a plurality of third green sheets made of piezoelectric powder. Forming a conductive layer on the inner walls of the first through hole and the second through hole communicating with each other, and dividing the fired body in the alignment direction of the plurality of through holes. It is.

  In the first ink jet printer head of the present invention, the first or second piezoelectric drive electrode formed on the first piezoelectric substrate and the second piezoelectric substrate sandwiches the ink flow path groove, and the first piezoelectric printer head is formed. When the drive electrode and the second piezoelectric drive electrode are driven synchronously, the amount of deformation required for the piezoelectric substrate (ink channel groove compression amount) can be ½ that of a conventional piezoelectric substrate that is driven on one side. Therefore, crosstalk can be prevented even if the ink flow path grooves are brought close to each other.

  In the second ink jet printer head of the present invention, the first piezoelectric drive electrode, the second piezoelectric drive electrode, and the pair of third piezoelectric drive electrodes surround the four sides of the ink flow path groove. In addition to the effects of the first ink jet printer head, when the pair of third piezoelectric drive electrodes are driven in synchronization with the first and second drive electrodes corresponding to the predetermined ink flow path grooves, The deformation of the piezoelectric substrate between the road grooves is positively suppressed, and a further crosstalk preventing effect is produced.

  The third ink jet printer head of the present invention corresponds to an ink jet printer head in which ink flow channel grooves are desired to be arranged in the left-right direction and the up-down direction, and in response to such a demand, the first ink jet printer of the present invention. This is a streamlined multilayer structure of the head.

  Therefore, in the third ink jet printer head of the present invention, the effect of preventing crosstalk generated by bringing the ink flow path groove close is the same as that of the first ink jet printer head of the present invention.

  The fourth ink jet printer head of the present invention corresponds to the ink jet printer head in which the ink flow path grooves are desired to be arranged in the left-right direction and the up-down direction. This is a streamlined multilayer structure of the head.

  Therefore, in the fourth ink jet printer head of the present invention, the effect of preventing crosstalk generated by bringing the ink flow path groove close is the same as that of the second ink jet printer head of the present invention.

  The fifth ink jet printer head of the present invention has a configuration in which a baking method is applied to bonding of piezoelectric substrates, and in the first to fourth ink jet printer heads of the present invention, an ink flow generated by bonding using an adhesive is used. It has the effect of eliminating the shape, volume, and cross-sectional area of the road groove.

  In the method for manufacturing a piezoelectric substrate of the present invention, the conductive layer formed on the inner wall of the through hole can be used as a connection terminal for connecting the piezoelectric drive electrode to the drive circuit. Therefore, in the piezoelectric substrate having the conventional structure, the connecting portion of the piezoelectric drive electrode is formed after the piezoelectric substrate is cut to a required dimension, and therefore, it is necessary to make the pitch wider than the ink flow path groove. No need for shaping.

  The ink jet printer head according to the present invention can reduce or eliminate interference during driving, thereby reducing crosstalk and narrowing the pitch of the ink flow path groove. Further, the conductive layer in the through hole can be connected to the external connection terminal. By doing so, the ink jet printer head is miniaturized.

  FIG. 1 is an explanatory diagram of the first and second embodiments of the present invention. In FIG. 1A, which shows the first embodiment of the present invention in a simplified manner, an inkjet printer head 21 is formed by bonding the lower surface of a piezoelectric substrate 23 to the upper surface of a piezoelectric substrate 22, and the piezoelectric substrates 22 and 23 are A plurality of green sheets mixed with piezoelectric powder are fired and integrated, and the piezoelectric substrates 22 and 23 are joined by a further firing process.

  A plurality of piezoelectric drive electrodes 24 corresponding to the ink flow path grooves 12 formed in the piezoelectric substrate 23 are formed in the piezoelectric substrate 22 having a flat upper surface, and a plurality (three in the figure) of ink flow path grooves 12 are formed on the lower surface. A plurality of piezoelectric drive electrodes 25 corresponding to the bottom surface (upper surface in the drawing) of the ink flow path groove 12 are formed in the piezoelectric substrate 23 on which the is formed.

  The piezoelectric substrates 22 and 23 are integrated by stacking and firing a plurality of piezoelectric green sheets, and the ink flow path grooves 12 of the piezoelectric substrate 23 are formed by machining after firing the green sheets.

  When a predetermined synchronous drive voltage is applied to the piezoelectric drive electrodes 24 and 25 each having a plurality of electrode patterns, the inkjet printer head 21 is locally applied to the piezoelectric substrates 22 and 23 as indicated by broken lines in the figure. Deformation occurs, and the corresponding ink flow path groove 12 is compressed. As a result, ink comes to fly from the nozzle communicating with the compressed ink flow path groove 12. However, since the amount of deformation generated in the piezoelectric substrates 22 and 23 is smaller than that of the conventional piezoelectric substrate 10, interference with the adjacent ink flow path grooves 12 is remarkably reduced.

Next, an example of a specific method for manufacturing the piezoelectric substrates 22 and 23 will be described. However, the piezoelectric drive electrodes 24 and 25 are composed of conductor patterns having the same shape. For the production of the piezoelectric substrates 22 and 23, a plurality of green sheets having a size larger than the dimensions of the piezoelectric substrates 22 and 23 and having a thickness of about 50 μm is a PNN piezoelectric powder having a particle size of about 1.0 mm, for example, Pb (Ni _1/3 Nb _2/3 ) O ₃ , PbTiO ₃ and PbZrO ₃ are mixed at a weight ratio of 0.5: 0.35: 0.15, and PVB (organic binder: polyvinyl petital) and DBP (plastic) are mixed. Agent: dibuvinyl butyral) and ethanol (organic solvent) are mixed to form a slurry, and the slurry is prepared by the doctor blade method.

  A green sheet having a desired size is punched from the green sheet, for example, a 100 mm square green sheet is formed by punching. A part of the 100 mm square green sheet is used as it is as the first green sheet, while the other is used as the second green sheet on the surface by a screen printing method using Ag-P paste. An electrode wiring pattern is formed. The electrode wiring pattern becomes a part of the piezoelectric drive electrode 24 or 25.

  The piezoelectric substrate 22 is fired by stacking a plurality of first green sheets and second green sheets, for example, 30 first green sheets are stacked, and four second green sheets are stacked thereon, 12 sheets of the first green sheets are stacked thereon, a pressing force of about 50 MPa is applied, and they are integrated by heat treatment at 80 ° C. for 1 hour.

  After that, degreasing treatment (removing PVB) in an electric furnace heated to about 500 ° C. for about 4 hours, and further firing in an electric furnace heated to about 1100 ° C. for about 4 hours, followed by cutting to a predetermined size Thus, the piezoelectric substrate 22 is completed.

  The piezoelectric substrate 23 in which the piezoelectric drive electrode 25 has the same conductor pattern combination as the piezoelectric drive electrode 24 is fired by stacking a plurality of first green sheets and second green sheets, for example, 14 first green sheets. After stacking four sheets, four second green sheets are stacked on top of each other, and further twelve first green sheets are stacked thereon, and then, integration processing, degreasing processing, and firing processing similar to those of the piezoelectric substrate 22 are performed.

  After that, when the ink channel groove 12 having a width of 200 μm and a depth of 400 μm is formed with a dicing saw, the piezoelectric substrate 23 is completed. Therefore, after polishing and flattening the upper surface of the piezoelectric substrate 22 and the lower surface of the piezoelectric substrate 23 (the surface on which the ink flow path grooves 12 are formed) by about 200 μm, the lower surface of the piezoelectric substrate 23 is superimposed on the upper surface of the piezoelectric substrate 22. Heat treatment is performed at about 1100 ° C. for 3 hours. Then, the piezoelectric substrates 22 and 23 are joined, and the ink jet printer head 21 is completed.

  In FIG. 1B, which shows the second embodiment of the present invention in a simplified manner, the ink jet printer head 26 is formed by bonding the lower surface of the piezoelectric substrate 27 to the upper surface of the piezoelectric substrate 22, and the piezoelectric substrates 22 and 27 are A plurality of green sheets mixed with piezoelectric powder are fired and integrated, and the piezoelectric substrates 22 and 27 are joined by further firing.

  A plurality of piezoelectric drive electrodes 24 corresponding to the ink flow path grooves 12 formed in the piezoelectric substrate 27 are formed in the piezoelectric substrate 22 having a flat upper surface, and a plurality (three in the figure) of ink flow path grooves 12 are formed on the lower surface. In the piezoelectric substrate 27 on which are formed, a plurality of piezoelectric drive electrodes 25 having a conductor pattern having the same shape as the piezoelectric drive electrodes 24 corresponding to the bottom surface (upper surface in the drawing) of the ink flow channel groove 12, and the ink flow A plurality of piezoelectric drive electrodes 28 corresponding to the sides of the road groove 12 are formed.

  The piezoelectric substrates 22 and 27 are integrated by stacking and firing a plurality of piezoelectric green sheets, and the ink flow path grooves 12 of the piezoelectric substrate 27 are formed by machining after firing the green sheets.

  The ink jet printer head 26 includes a piezoelectric drive electrode that surrounds a predetermined ink flow path groove 12, that is, piezoelectric drive electrodes 24 and 25 positioned above and below the predetermined ink flow path groove 12, and a pair of piezoelectric drives positioned on the sides thereof. When a predetermined synchronous drive voltage is applied to the electrodes 28, the piezoelectric substrates 22 and 27 are locally deformed as shown by the broken lines in the figure, and the corresponding ink flow channel grooves 12 are compressed. As a result, ink comes to fly from the nozzle communicating with the compressed ink flow path groove 12.

  However, the pair of piezoelectric drive electrodes 28 applies a voltage in a direction that suppresses deformation of the piezoelectric substrate 22 by the piezoelectric drive electrodes 24. As a result, the amount of deformation generated in the piezoelectric substrates 22 and 27 is smaller than that of the conventional piezoelectric substrate 10, and the piezoelectric drive electrode 28 suppresses interference with the adjacent ink flow channel groove 12, so that the conventional technology is used. The problem interference is surely resolved.

  In the ink jet printer head 26, the piezoelectric substrate 22 is manufactured by the same method as that of the ink jet printer head 21, so that the description thereof is omitted, and a specific method for manufacturing the piezoelectric substrate 27 will be described.

For the production of the piezoelectric substrate 27, a plurality of green sheets having a size larger than the size of the piezoelectric substrate 27 and a thickness of about 50 μm is a PNN piezoelectric powder having a particle size of about 1.0 mm, for example, Pb (Ni _1/3 Nb _2/3 ) O ₃ , PbTiO ₃ and PbZrO ₃ are mixed at a weight ratio of 0.5: 0.35: 0.15, and PVB (organic binder), DBP (plasticizer) and ethanol (organic solvent) Are mixed to form a slurry, which is prepared from the slurry by a doctor blade method.

  A green sheet having a desired size is punched from the green sheet, for example, a 100 mm square green sheet is formed by punching. A part of the 100 mm square green sheet is used as it is as the first green sheet, while the other part is used as the second green sheet on the surface by a screen printing method using Ag-P paste. In addition, a plurality of electrode wiring patterns having a width of 40 μm are formed on the surface as a third green sheet by a screen printing method using an Ag—P paste. The electrode wiring pattern of the second green sheet becomes a part of the piezoelectric driving electrode 25, and the electrode wiring pattern of the third green sheet becomes a part of the piezoelectric driving electrode 28.

  The piezoelectric substrate 27 is fired by stacking a plurality of first green sheets, second green sheets, and third green sheets, for example, twelve first green sheets, and a third green sheet thereon. Are stacked, four second green sheets are stacked thereon, and further 12 first green sheets are stacked, and a pressing force of about 50 MPa is applied and integrated by heat treatment at 80 ° C. for 1 hour.

  After that, degreasing treatment (removing PVB) for about 4 hours in an electric furnace heated to about 500 ° C., followed by baking in an electric furnace heated to about 1100 ° C. for about 4 hours, and cutting to a predetermined size. When the ink flow path groove 12 having a width of 200 μm and a depth of 400 μm is formed by a dicing saw, the piezoelectric substrate 23 is completed.

  Therefore, the upper surface of the piezoelectric substrate 22 and the lower surface of the piezoelectric substrate 27 (the surface on which the ink flow channel grooves 12 are formed) are each polished and planarized by about 200 μm, and then the lower surface of the piezoelectric substrate 27 is superimposed on the upper surface of the piezoelectric substrate 22. Heat treatment is performed at about 1100 ° C. for 3 hours. Then, the piezoelectric substrates 22 and 27 are joined, and the ink jet printer head 26 is completed.

  FIG. 2 is an explanatory diagram of the third and fourth embodiments of the present invention. In FIG. 2A, which shows a simplified third embodiment of the present invention, an ink jet printer head 31 is formed by bonding the lower surface of the piezoelectric substrate 23 to the upper surface of the piezoelectric substrate 22 via an adhesive 32. The piezoelectric substrates 22 and 23 are integrally formed by firing a plurality of green sheets mixed with piezoelectric powder.

  The ink jet printer head 21 and the ink jet printer head 31 described above are common by using the piezoelectric substrates 22 and 23, but their joining means are different. That is, the ink jet printer head 21 uses the adhesive 32 in the ink jet printer head 31 while the piezoelectric substrates 22 and 23 are bonded by baking.

  As the adhesive 32, an adhesive used for joining the piezoelectric substrate 10 and the ink flow path plate 11 in the conventional ink jet printer head, that is, a film-like adhesive called a dry film resist, a liquid resist, a photosensitive polyimide, or the like is used. it can.

  The manufacturing method of the piezoelectric substrates 22 and 23 is the same as that of the inkjet printer head 21. Accordingly, an embodiment of a method for joining the piezoelectric substrates 22 and 23 using a dry film resist as the adhesive 32 will be described.

An adhesive (dry film resist) 32 that does not have a hardness unless exposed to light is mounted on the upper surface of the piezoelectric substrate 22 and then exposed to, for example, 100 mj / cm ² of ultraviolet light, and then the piezoelectric substrate 23 is placed on the adhesive 32. In a state where the piezoelectric substrate 23 is pressed against the adhesive 32 with an appropriate pressing force, thermocompression bonding is performed at 150 ° C. for about one hour. However, the piezoelectric substrate 23 is in contact with the adhesive 32 at the bottom surface on which the ink channel grooves 12 are formed.

  The ink jet printer head 31 is used in the same manner as the ink jet printer head 21 described above, and can significantly reduce interference that has been a problem in the prior art.

  In FIG. 2B, which shows a simplified third embodiment of the present invention, an ink jet printer head 36 is formed by bonding the lower surface of the piezoelectric substrate 23 to the upper surface of the piezoelectric substrate 22 via an adhesive 32. The piezoelectric substrates 22 and 23 are integrally formed by firing a plurality of green sheets mixed with piezoelectric powder.

  The ink jet printer head 26 and the ink jet printer head 36 described above are common by using the piezoelectric substrates 22 and 27, but their joining means are different. That is, the ink jet printer head 26 uses the adhesive 32 in the ink jet printer head 36 while the piezoelectric substrates 22 and 27 are bonded by baking.

As with the inkjet printer head 31, for example, a dry film resist is used for the adhesive 32, and the bonding method is the same as that of the inkjet printer head 31.
Such an ink jet printer head 36 can be used in the same manner as the ink jet printer head 26 described above, and can eliminate interference that has been a problem in the prior art.

FIG. 3 is an explanatory view of a fifth embodiment of the present invention. The ink jet printer head 41 includes an adhesive 32 _-1 and a pair of piezoelectric substrates 42 _-1 and 42 _-2 and a piezoelectric substrate 43 which are superposed on each other. _Joined using 32-2. However, the piezoelectric substrate 42 _-1 and 42 _-2 and 43 is formed by integrally firing a plurality of green sheets obtained by mixing a piezoelectric powder.

Piezoelectric substrates 42 _-1 and 42 _-2 having a plurality (four in the figure) of ink flow channel grooves 12 formed on the upper surface are formed in the plurality of piezoelectric substrates 42 _-1 and 42 _-2 corresponding to the respective bottom surfaces of the ink flow channel grooves 12. a piezoelectric driving electrode 44, a plurality of piezoelectric driving electrodes 45 corresponding to the ink flow path groove 12 of the lower substrate is formed, a piezoelectric substrate to block the ink flow path groove 12 of the piezoelectric substrate 42 _-2 higher than the piezoelectric substrate 42 _-1 A plurality of drive electrodes 46 corresponding to each of the ink flow path grooves 12 are formed in 43.

In such an ink jet printer head 41, the piezoelectric substrate 42 _-1 and 42 _-2 and 43 a method of manufacturing a, particularly the method of forming the piezoelectric driving electrodes 44 and 45 and 46 and the ink flow path groove 12, the piezoelectric substrate 22 of the ink jet printer head 21 and 23 are the same as those of the method of bonding the piezoelectric substrate 42 _-1 and 42 _-2 in the adhesive 32 _-1, a method of bonding the piezoelectric substrate 42 _-2 and 43 with an adhesive 32 _-2 In the inkjet printer head 31, the method is the same as the method of joining the piezoelectric substrates 22 and 23 together.

However, the adhesives 32 _-1 and 32 _-2 used for bonding between substrates in the ink jet printer head 41 are adhered to the surface of the pair of bonding surfaces where the ink flow channel 12 is not formed, that is, the adhesive. 32 _-1 is affixed to the lower surface of the piezoelectric substrate 42 _-2 exposure process (curing process), the adhesive 32 _-2 exposure by sticking to the lower surface of the piezoelectric substrate 43 (curing process).

  The ink jet printer head 41 is configured to enable two-color printing, and is driven in the same manner as the ink jet printer head 21 described above, and can significantly reduce interference that has been a problem in the prior art.

FIG. 4 is an explanatory view of a sixth embodiment of the present invention. The ink jet printer head 48 includes an adhesive 32 _{-1 in} a state where a pair of piezoelectric substrates 49 _-1 and 49 _-2 and a piezoelectric substrate 43 are stacked. _Joined using 32-2. However, _-1 and 49 _-2 piezoelectric substrate 49 is formed by integrally firing a plurality of green sheets obtained by mixing a piezoelectric powder.

Piezoelectric substrates 49 _-1 and 49 _-2 having a plurality (four in the figure) of ink flow channel grooves 12 formed on the upper surface correspond to the respective bottom surfaces of the ink flow channel grooves 12 in the substrates (in FIG. The figure shows four sets of piezoelectric drive electrodes 44, a plurality (four sets of figures) of piezoelectric drive electrodes 45 corresponding to the ink flow path grooves 12 of the lower substrate, and a plurality of (shown in FIG. 6 sets of drive electrodes 50 are formed.

In such an ink jet printer head 48, a method of manufacturing a piezoelectric substrate 49 _-1 and 49 _-2, and 43, in particular the method of forming the drive electrodes 44 and 45 and 46 and 50 and the ink flow path groove 12, the piezoelectric substrate of an ink jet printer head 26 22 and 27, and the method of bonding the piezoelectric substrates with the adhesives 32 _-1 and 32 _-2 is the same as that of the inkjet printer head 41 in the piezoelectric substrates 42 _-1 and 42 _-2 and 42 _-2 . This is the same as the method of joining 43.

  The ink jet printer head 48 is configured to enable two-color printing, similar to the ink jet printer head 41, and can be driven in the same manner as the ink jet printer head 36 described above to eliminate interference that has been a problem in the prior art. become.

Figure 5 is an explanatory view of a seventh embodiment of the present invention, an inkjet printer head 51 has superimposed four piezoelectric substrate 49 _-1 and 49 _-2 and 49 _-3 and 49 _-4, and the piezoelectric substrate 43 state, using an adhesive 32 _-1 and 32 _-2 and 32 _-3 and 32 _-4 formed by joining. However, the four piezoelectric substrates 49 _-1 to 49 _-4 are integrated by baking a plurality of green sheets mixed with piezoelectric powder.

In such an ink jet printer head 51, the production method and methods for their bonding the piezoelectric substrate 43 and 49 _-1 to 49 _-4, is omitted for the same as in the previous example, four piezoelectric substrate 49 _-1 ~ The reason why 49 _-4 is overlapped is to enable black single color printing and full color printing. For example, when black ink is supplied to the uppermost ink flow path 12, the ink of the third and lower stages is used. One color from among red ink, blue ink, and yellow ink is specified and supplied to the flow channel 12.

  The ink jet printer head 51 is driven in the same manner as the ink jet printer head 21 described above, and can significantly reduce interference that has been a problem in the prior art, and also enables black single color printing and full color printing.

FIG. 6 is an explanatory view of a green sheet used in the eighth embodiment of the present invention, and FIGS. 7 and 8 are explanatory views of the eighth embodiment of the present invention. In FIG. 6, an inkjet printer head according to an eighth embodiment of the invention has a piezoelectric green sheet 61 _{-1 in} which a plurality (five in the figure) of through holes 62 are arranged in a predetermined portion (four in the figure in the figure). A piezoelectric green sheet 61 _-2 in which a plurality of through holes 62 are arranged in a predetermined portion and a plurality of (four in the figure) piezoelectric conductive electrode configuration strip-shaped conductor patterns _63-1 are formed; a plurality of through holes 62 are aligned in the part, and, to use a piezoelectric green sheet 61 _-3 piezoelectric drive electrode configuration for rectangular conductor pattern 63 _-2 is formed, the mere piezoelectric green sheet 61 _-4.

Predetermined portion of the through hole 62 in the green sheet 61 _-1 to 61 _-3, a position that communicates when stacked green sheets 61 _-1 to 61 _-3, the same conductive pattern 63 _-1 green sheet 61 _-2 A plurality of through-holes 62 (four from the left end among the five aligned) in the through-holes 62 formed in a predetermined portion extend to the front, and the conductor pattern 63 _-2 has four conductors. corresponding to the pattern 63 _-1, and the predetermined (FIG right end in five aligned) communicating with the through hole 62 of the.

The green sheets 61 _{-1 to} 61 _-4 are made of PNN piezoelectric powder having a particle size of about 1.0 mm, for example, Pb (Ni _1/3 Nb _2/3 ) O ₃ , PbTiO ₃ and PbZrO ₃ , 0.5: It is mixed at a weight ratio of 0.35: 0.15, further PVB (organic binder), DBP (plasticizer) and ethanol (organic solvent) are mixed to form a slurry, and the slurry is made into a sheet by the doctor blade method, and cut into desired size to create the green sheet 61 _-4 desired number. Green sheet 61 _-1 is made by forming a through hole 62 in the green sheet 61 _-4, the green sheet 61 _-2 be to form a through-hole 62 and the conductor pattern 63 _-1 on the green sheet 61 _-4, green sheet 61 _-3 is obtained by forming a through-hole 62 and the conductor pattern 63 _-2 green sheet 61 _-4.

The conductor pattern 63 _-1 and 63 _-2, in which print the Ag-Pd paste was dried it. Then, a plurality of conductor patterns 63 _-1 of the same green sheet 61 _-2 individual when completed as a piezoelectric substrate corresponds to a different ink flow path grooves, the positive voltage terminal of the power supply is applied at the time of driving the piezoelectric substrate On the other hand, the conductor pattern 63 _-2 corresponds to a plurality of ink flow path grooves, and is connected to the ground terminal or the minus terminal of the power supply device when the piezoelectric substrate is driven.

7, the green sheet laminate 66, a plurality (figure 7 sheets) on which stacked green sheets 61 _-4, a plurality alternately green sheets 61 _-3 and 61 ₂ (Fig. 4 sheets And at least one green sheet 61 _-1 is stacked thereon.

Next, after applying a pressing force of about 10 MPa and integrating the stacked green sheets 61 _{-1 to} 61 _-4 by a treatment at 60 ° C. for 5 minutes, a firing treatment at about 1000 ° C. for 10 hours is performed. A conductive layer 67 of Ni is formed on the inner wall of the through hole 62 by electroless plating.

  Note that when the conductive layer 67 is formed, a Ni layer is also deposited on the upper surface of the fired green sheet laminate 66. After the Ni layer is removed by the polishing process, a line with an arrow in FIG. Then, cutting with a dicing saw, that is, cutting along the alignment line of the through hole 62, cutting to remove the left and right unnecessary portions, and cutting processing to divide the left and right into two at the central portion are performed.

As a result, four piezoelectric substrates 71 shown in FIG. 8 can be obtained from the fired green sheet laminate 66. 8A is a perspective view as viewed from the front surface, and FIG. 8B is a perspective view as viewed from the rear surface. In the front surface of the piezoelectric substrate 71 corresponding to the above-described piezoelectric substrate 22, the ink flow channel groove is formed. The end face of the corresponding drive electrode group (the figure shows four sets of piezoelectric drive electrodes) 72 is exposed, and on the rear face, connection terminals 73 _-1 , 73 _-2 , 73 _-3 and 73 _-4 for applying voltage to the drive electrodes. and 73 _-5 is exposed.

The connection terminals 73 _{-1 to} 73 _-5 are part of the conductive layer 67, that is, one side of the conductive layer 67 divided into two by the cutting of the green sheet laminate 66. Then, the connection terminals 73 _{-1 to} 73 _-4 to which the rear end portion of the conductor pattern 63 _-1 shown in FIG. 6 is connected are connected to a piezoelectric substrate driving plus terminal of a power supply device (not shown), and the conductor pattern shown in FIG. 63 connection terminal 73 _-5 the rear end is connected _-2 is connected to the ground terminal or the negative terminal piezoelectric substrate driving power supply (not shown), the piezoelectric substrate 71 is driven.

The piezoelectric substrate 71 can be made smaller than the conventional piezoelectric substrate 10 shown in FIG. 15 because the connection terminals 73 _{-1 to} 73 _-5 for the power supply device are formed at the same pitch as the ink flow path grooves.
In the fifth, sixth and seventh embodiments of the present invention, an adhesive is used for bonding between the piezoelectric substrates. However, as described in the first and second embodiments of the present invention, it is possible to perform fired bonding without using an adhesive between the piezoelectric substrates. Accordingly, the adhesive can be eliminated from the configurations of the fifth, sixth and seventh embodiments of the present invention.

Explanatory drawing of the 1st and 2nd Example of this invention Explanatory drawing of the 3rd and 4th Example of this invention Explanatory drawing of 5th Example of this invention Explanatory drawing of the 6th example of the present invention. Explanatory drawing of 7th Example of this invention Explanatory drawing of the green sheet used for the 8th example of the present invention Explanatory drawing of the 8th Example of this invention (the 1) Explanatory drawing of the 8th Example of this invention (the 2) A perspective view showing an outline of an inkjet printer Disassembled schematic diagram of flow-path plate type piezoelectric inkjet head Sectional view of the piezoelectric inkjet head shown in FIG. Illustration of interference in a piezoelectric inkjet head Explanatory drawing of interference prevention type piezoelectric inkjet head between ink flow paths Illustration of green sheet used for conventional piezoelectric substrate Illustration of a conventional piezoelectric substrate with a built-in drive electrode

Explanation of symbols

10 ₋₁ , 10 ₋₂ , 10 ₋₃ , 61 ₋₁ , 61 ₋₂ , 61 ₋₃ , 61 ₋₄ Green sheet 12 Ink channel groove 16 ₋₁ , 16 ₋₂ , 63 ₋₁ , 63 ₋₂ Piezoelectric Conductive patterns 21, 26, 31, 36, 41, 48, 51 for drive electrodes Inkjet printer heads 22, 23, 27, 42 ₋₁ , 42 ₋₂ , 49 ₋₁ , 49 ₋₂ , 49 ₋₃ , 49 _{− 4} , 71 Piezoelectric substrates 24, 25, 28, 44, 45, 46, 50 Piezoelectric drive electrodes 32, 32 ₋₁ , 32 _-2 Adhesive 62 Through hole 67 Conductor layers 73 ₋₁ , 73 _-2 in the through hole, 73 _-3 , 73 _-4 , 73 _-5 piezoelectric substrate connection terminals

Claims (3)

The lower surface of the first piezoelectric substrate on which the ink flow path grooves are formed, is bonded the upper surface of the second piezoelectric substrate, a first piezoelectric substrate, a corresponds to a bottom surface of said ink flow path grooves 1 a piezoelectric drive electrode located on the side of said ink flow path grooves, the third piezoelectric drive electrodes to deform the inhibit direction deformation of the second piezoelectric substrate by at least a second piezoelectric driving electrodes are formed , wherein the second piezoelectric substrate, said second piezoelectric driving electrodes corresponding to the ink flow path groove is formed, the first piezoelectric drive electrode positioned vertically across said ink flow path grooves and As a result of compressing the ink flow path groove in the vertical direction by deforming the first piezoelectric substrate and the second piezoelectric substrate by applying a voltage to the second piezoelectric drive electrode, the compressed ink flow path groove ink flies from a nozzle communicating with the ink-jet pre A Taheddo,
Said first piezoelectric substrate, a first green sheet of the plurality sheets made of piezoelectric powder, a plurality electrode patterns of the first piezoelectric drive electrode is formed in a predetermined portion of the first green sheet the overlapping and second green sheets, the first green plurality of third green sheets on which the electrode pattern of the ink flow path grooves to become notch and said third piezoelectric drive electrode is formed in a predetermined portion of the sheet Integrated by firing process,
Said second piezoelectric substrate, a plurality of the first green sheets, the first green sheets plurality of fourth green electrode pattern of the second piezoelectric driving electrodes formed on a predetermined portion of The sheet must be integrated by baking process,
Inkjet printer head characterized by the above. By bonding stacked plurality of first piezoelectric substrate in which the ink flow path grooves are formed on the upper surface, the ink flow path grooves on the stacked direction is more disposed, an upper surface of said first piezoelectric substrate topmost second piezoelectric substrate is joined to, the said respective first piezoelectric substrate, a first piezoelectric driving electrodes corresponding to the bottom surface of the ink flow path grooves are formed on the first piezoelectric substrate, a second piezoelectric driving electrodes, wherein in correspondence with the bottom first piezoelectric drive electrode is formed corresponding to the ink flow path grooves of the other of the first piezoelectric substrate to be overlaid to the lower than the first piezoelectric substrate is located on the side of the ink flow path grooves are the third piezoelectric drive electrodes to deform at least suppress facing the deformation of the said by the second piezoelectric driving electrode and the second piezoelectric substrate is formed, wherein the second piezoelectric substrate, a first piezoelectric substrate of the uppermost A second piezoelectric drive electrode is formed corresponding to the ink flow path grooves, by applying a voltage to the first piezoelectric drive electrode and the second piezoelectric drive electrode positioned vertically across said ink flow path grooves An ink jet printer head in which the first piezoelectric substrate and the second piezoelectric substrate are deformed to compress the ink flow channel groove in the vertical direction, so that ink is ejected from a nozzle communicating with the compressed ink flow channel groove. Because
It said first piezoelectric substrate, a plurality of first green sheets made of piezoelectric powder, the first serving as the ink flow path grooves to a predetermined portion of the green sheet notch and said third piezoelectric driving electrodes a second green sheet of a plurality of electrode patterns are formed, and the first said to a predetermined portion of the green sheet a first piezoelectric driving a plurality of third electrode pattern is formed of an electrode of the green sheet, are those that are integrated in the sintering process of repeating the first green sheet of a predetermined portion on the second fourth plurality of electrode patterns are formed of a piezoelectric drive electrode of the green sheet,
Said second piezoelectric substrate, in which are integrated in the sintering process of repeated a plurality of the first green sheet and the plurality of the fourth green sheet,
Inkjet printer head characterized by the above.   The ink jet printer head according to claim 1, wherein the joining according to claim 1 is a joining by firing.

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