JPH0445946A - On-demand type ink jet print head - Google Patents

Abstract

PURPOSE:To prevent an ink from invading piezoelectric devices by providing spaces forming ink sumps oppositely to the free edges of a piezoelectric element array and arranging a partition member oppositely, while furthermore arranging cutoff partition member so as to cut off the spaces from the free edges of the piezoelectric element array. CONSTITUTION:A cavity section is partitioned into independent cavities 11 partitioned at every piezoelectric element by cavity partitions b52 made of a material equivalent to that of array partitioning sections 5. The cavities 11 are cut off from the piezoelectric elements 4 completely by cavity partitions a51 as a cutoff partition material made by a material equivalent to the string partitioning section 5, and the cavity partitions a51 are stuck fast also to a substrate 1. Faces facing the piezoelectric elements 4 in the cavities 11 and the cavity partitions a51 are made of partition blocks 3 such as ceramic or plastic or metal as a facing partition member, and the partition blocks 3 are fixed to the substrate 1. When piezoelectric element blocks are to be fixed to the substrate 1, a quantity of stretch of the piezoelectric element 4 works effectively on free edges of the cavities 11.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention is capable of ejecting ink as droplets or mist when printing data is input, and forming dots on recording paper with the ink droplets or mist. The present invention relates to an on-demand type ink jet type 1-type print head. Specifically, it is widely used in computer terminals, color printers, etc.

[Conventional technology]

On-demand inkjet printheads are broadly divided into three types.The first type is equipped with a heater that instantly vaporizes the ink directly below the nozzle or on the wall.
This is a so-called bubble jet type in which ink droplets are generated and blown away by the expansion pressure during vaporization, and the second type is a so-called bubble jet type in which a piezoelectric element that deforms in response to a signal is installed in the container that forms the ink reservoir, and the ink droplets are generated when deformed. A third type uses pressure to make ink droplets fly, and a third type has a piezoelectric element disposed in the ink reservoir facing the nozzle, and this pressure
The expansion and contraction of the IE element generates dynamic pressure in the nozzle area, causing ink droplets to fly.

The on-demand inkjet print head of the third type in Section 2 has a plurality of nozzle openings formed in the wall of a container constituting an ink tank, as shown in Japanese Patent Publication No. 1989-8953. At the same time, piezoelectric elements are disposed in the container so that the expansion and contraction directions coincide with each other so as to face the opening of each nozzle. This print head applies a print signal to a piezoelectric element to cause the piezoelectric element to expand, and the dynamic pressure of the ink generated at this time causes ink droplets to fly out from the nozzle to form a driver I on the printing paper. be.

In this type of print head, the surface electrodes of the piezoelectric elements in the ink reservoir are not corroded by additives, such as surfactants, added to increase the adhesion or permeability of the ink to the recording paper. In addition, there is a problem in that electrical insulation between each piezoelectric element must be ensured.

Furthermore, it is desirable for the droplet formation efficiency and flight to be large, but since the unit length and expansion/contraction rate per unit of the piezoelectric element are extremely small, it is necessary to obtain the droplet formation efficiency and flight force required for printing. However, there is a problem in that the dynamic pressure of the ink is concentrated at the nozzle opening, and it is necessary to apply a high voltage, which complicates the structure, drive circuit, and electrical insulation measures.

” The following proposals are presented to solve the second problem. First, there are many methods for protecting the surface electrodes of piezoelectric elements, such as coating a thin resin film, forming a thin film hollow, or forming an oxide film so as not to impair the characteristics of the piezoelectric element. , the method of connecting the partially exposed positive and negative electrodes of the piezoelectric element to the drive circuit side becomes complicated, and there are problems with reliability due to peeling and damage of the protective film and high cost due to the complexity of the manufacturing process. In addition, there are methods for electrically insulating between each piezoelectric element, such as using insulating ink and insulating the surface electrode of the piezoelectric element.Table r
An example of insulation treatment for Iri electrodes is the formation of an insulating film, but this has the same problems as the aforementioned protection treatment. Regarding the use of insulating inks, for example, insulating oil-based inks are limited or specified in terms of component materials in order to ensure printing quality, especially in relation to measures against bleeding, so usage and storage conditions are also limited. There are problems in that the cost is relatively high and the structure is also complicated. Furthermore, in order to obtain the droplet formation efficiency and flying force required for printing, the dynamic pressure of the ink is concentrated in one nozzle opening. This is a method of making the volume larger than 1 part. Specifically, there is a method of providing a gap and a horn shape in the thickness direction of a member having a nozzle opening, a conical shape shown in Japanese Patent Publication No. 8953/1980, and a method of providing an ink reservoir part. A number of proposals have been made, including methods for making the shape protrude from the sides. but,
When implementing such a method, a complex shape is formed on the nozzle opening (on the ink reservoir side), that is, on the inner wall of the container, which extremely limits the processing methods and results in extremely high costs. Ta.

In addition, as a method of not applying high voltage to obtain the flying force required for printing, Japanese Patent Publication No. 63-295
As shown in Japanese Patent No. 269, a piezoelectric element for an inkjet print head has been proposed in which electrodes and piezoelectric materials are alternately laminated in a sandwich pattern. According to this piezoelectric element, since the distance between the electrodes can be made as small as possible, there is an effect that the voltage of the drive signal can be lowered.

[Problem to be solved by the invention]

However, since it is difficult to mold such a piezoelectric element into a small size, there is a problem that its applications are limited.

The purpose of the present invention is to solve the above-mentioned problems.The first purpose of the present invention is to provide a novel on-demand type that is compatible with ink and has high reliability by preventing the surface electrode of a piezoelectric element from being eroded by ink. An object of the present invention is to provide an inkjet print head.

A second object of the present invention is to provide a novel on-demand inkjet printing head I that has high ink compatibility and reliability by ensuring electrical insulation between each piezoelectric element.

A third object of the present invention is to provide a new on-demand type inkjet I-type print head that has sufficient flying force to form ink droplets with high efficiency at the lowest possible voltage.

A fourth object of the present invention is to provide a compact, high-density, and practical on-demand inkjet printhead.

A fifth object of the present invention is to provide an on-demand inkjet print head that is inexpensive and has excellent mass productivity.

[Failure to solve the problem]

In the on-demand inkjet print head of the present invention, a piezoelectric plate made of a piezoelectric material and a conductive material is cut to a predetermined width, one end is fixed to or abuts on a base, and the (Ii! end is set as a free end). an array of piezoelectric elements disposed, an opposing partition member disposed facing the free end to form a space forming an ink reservoir, and an opposing partition member opposing the opposing partition member so as to block the space from the free end. It is characterized by comprising: a blocking partition member disposed on the free end side of the space, a nozzle member having one nozzle opening facing the space, and a row partition member disposed between the rows of piezoelectric elements. do.

The present invention is also characterized in that the blocking partitions 1i and 7J members extend from the row partitioning members.

Furthermore, it is characterized in that the row partition member extends so as to partition the space for each piezoelectric element.

Furthermore, the shielding partition member or the row partition member is made of an electrically insulating material.

Furthermore, the shielding member 1i7J or the row partition member is made of a material that can be injected and hardened.

Furthermore, the piezoelectric plate is characterized in that the piezoelectric plate is formed by laminating a paste piezoelectric material and a conductive material alternately in layers and firing the layers.

[Effect]

In the on-demand inkjet print head of the present invention, the on-demand inkjet print head according to the present invention is constructed by providing a space facing the free end of a row of piezoelectric elements and forming an ink reservoir, and arranging an opposing partition member to connect the space to the piezoelectric element. By arranging the blocking partition member so as to block the free end of the element array, it is possible to prevent ink from entering the piezoelectric element side, and to increase the adhesion or permeability of ink to the recording paper. Erosion of the electrodes on the surface of the piezoelectric element due to added additives such as surfactants is eliminated.

Further, since the blocking partition member is extended from the row partition member and is integrally formed, the strength is increased and the peeling resistance is improved.

Furthermore, by extending the column partitioning member so as to partition the space forming the ink reservoir for each row of piezoelectric elements, and making each space independent, the dynamic pressure applied to the ink by the expansion and contraction of the piezoelectric elements can be applied to the nozzle opening adjacent to the nozzle opening. By eliminating directional escape and interference, the efficiency of ink droplet formation is increased and the flying force is increased.

Furthermore, since the cut-off partition member or the row partition member is made of an electrically insulating material, each piezoelectric element is completely electrically insulated, which prevents leaks and short circuits between each piezoelectric element. will no longer occur.

Furthermore, the piezoelectric element array is made by cutting a piezoelectric plate made by laminating paste-like piezoelectric material and conductive material alternately in layers and firing them into a predetermined width, so that sufficient flying force can be obtained with a low voltage. I can do it.

〔Example〕

The details of the present invention will be explained below using examples with reference to the drawings.

1 to 5 show the configuration of a first type of on-demand inkjet type print head according to the present invention, in which FIG. 1 is an external perspective view, FIG. 2 is a plan view, and FIG. The figure is a cross-sectional view of the drive unit taken along the line A-A' in Figure 2 and centered on the nozzle part, Figure 4 is a cross-sectional view taken along the line B-B' in Figure 2 and centered on the partition part, and Figure 5 2 is a plan view of the nozzle forming portion 7 provided with the nozzle 8 shown in FIG.

In FIGS. 3 and 4 and 5 and 12, the piezoelectric element 4 is fixed to the substrate 1 and the housing 2 by strong 15 adhesive or brazing. Pressure 7! The element 4 has internal electrodes arranged alternately in the direction y1 facing the cavity 11 so as to longitudinally vibrate in the piezoelectric constant d33 direction. Pressure? ! ! The external electrodes of the element 4 are formed over the entire upper and lower surfaces, and are electrically connected to the lead electrodes 14 formed on the substrate 1 via an adhesive, a brazing pad, or a conductive layer 9.

Furthermore, the gaps between the rows of piezoelectric elements 4 are filled with an electrically insulating resin material such as an adhesive or filler whose Young's modulus is 20% or less of that of the piezoelectric elements 4, and the material is cured. It forms a part. Further, the cavity portion is divided into independent cavities 11 for each piezoelectric element 4 by a cavity partition portion b52 made of the same material as the row partition portion 5.

Further, the cavity 11 and the piezoelectric element 4 are connected to a cavity partition part a51 which is a blocking partition member made of the same material as the row partition part 5.
The cavity partitioning portion a51 is also tightly adhered to the substrate 1.

piezoelectric element 4 and cavity partition part a in cavity 1]
The surface facing 51 is formed of a partition block 3 which is an opposing partition member made of ceramic, plastic, metal, etc., and partition block 3 is fixed to substrate 1. Further, the nozzle forming part 7 in which the nozzle 8 facing the cavity 11 is formed is located on the side opposite to the substrate 1 side of the cavity IJ, the partition block 3, the piezoelectric element 4, the housing 2, the cavity partition part a51, and the cavity partition part b52, respectively. A row partition part 5 that fills the gap between the rows of piezoelectric elements 4 between the ends
It is formed of a single material equivalent to the above to a predetermined thickness and size.

The on-demand type ink jet print head according to the present invention having the above-mentioned configuration will be described in detail while following the manufacturing process.

FIG. 6 is a detailed view of the substrate 1. The broken line a in the figure is the line for one unit, that is, one
The board 1 is designed using the head.

The number of sheets to be produced is determined by the number of nozzles in each head and the capacity of the manufacturing equipment. This substrate 1 is made of an insulating material, and a ceramic such as alumina, a glass substrate, or the like is used. Reference numeral 21 denotes a through hole for introducing ink, which penetrates through the back surface 17 by laser or molding. 22 is a conductive base for a conductive electrode made by firing a surface electrode, and is generally made of Ag/Pd type, A u / P d type, P
A t/Pd system is used. Of course, conductive paste (l!l) can also be used, and the thickness is 3/im~20μ
Up to m is preferred. The partition block 3 and the piezoelectric element block 34 are adhered onto this with adhesive No. 15. The adhesive is
A resin adhesive such as epoxy or silicone adhesive, Ag solder, or the like is used.

FIG. 7 is a diagram in which the partition block 3 and the piezoelectric element block 34 are bonded onto the substrate 1. At this point, the piezoelectric element 34
is a block state diagram that is not divided into each array.

This piezoelectric element block 34 has external electrodes covering the entire surface of each of the upper and lower surfaces. In addition, 31 in the figure is a gap with a predetermined thickness for forming a cavity in the future, and as shown in Figure 9, it is used for pasting a resist film or for pouring photolithographic resist, etc., and solidifying it. etc., is filled with a soluble resin 32 that can be removed later.

When fixing the piezoelectric element block 34 to the substrate 1, the end opposite to the cavity 11 side is fixed with a member having a Young's modulus equivalent to that of the high-strength piezoelectric element 4, thereby controlling the amount of expansion and contraction of the piezoelectric element 4. can effectively act on the free end side on the cavity 11 side. Therefore, in this embodiment, the housing 2 is made of a material with a high Young's modulus such as ceramics, and is arranged in close contact with the fixed end of the piezoelectric element 4. In order to further ensure the fixation, it is also possible to use an adhesive with a high Young's modulus between the substrate 1 and the piezoelectric element 4 and between the housing 2 and the piezoelectric element 4 at the portions 6 and 9 in FIG. For example, it is a glass frit phase, a ceramic base, etc., and can be fixed by firing or the like.

Furthermore, the piezoelectric element 4 will be explained in detail.

FIG. 8(a) shows the piezoelectric element block 34, and the reference numeral 40. 40. 40. ...... are conductive layers constituting one electrode, and 42°42
．． 42. . . . are conductive layers constituting the other electrode, and each conductive layer is made of piezoelectric materials 44, 44 . . . alternately parallel to each other. . . . in a sandwich manner, and one electrode 40, 40 .・・・・・・
・The conductive layer is exposed on one side (bottom side in the figure),
Also, the other electric fi42. 42. The conductive layer . Such a layered structure is achieved by forming an appropriate piezoelectric element material, such as a composite perovskite ceramic material based on titanate/lead zirconate, into a green sheet, printing internal electrode material on the surface using a printing method, and then printing the required number of sheets alternately. Laminate over and over. In this way, a predetermined number of sheets are formed, and pre-drying and sintering are performed to obtain a sintered body. This state is shown in FIG. 8(a). Conductive materials 47 and 48 are applied to the exposed surfaces of the rectangular parallelepiped and where the internal electrodes 42 and 40 are exposed, respectively, and dried or fired, as shown in FIG.
b). This is the piezoelectric element block 34, which is eventually divided into each array by inserting the sleeve I.46.

Independent lead members are connected to the conductive layer 47 connecting one electrode of each element configured in this way,
Further, a common lead member is connected to the conductive layer 48 connecting the other electrode. As a result, when an electric signal is applied between the independent lead members and the common lead member, the piezoelectric element to which the signal is selectively applied by the independent lead member will receive the same voltage between the electrodes via the conductive layer. are applied at the same time, the piezoelectric material between the electrodes simultaneously expands, the displacements of each layer are added up, and the free end side is displaced in the axial direction. Of course, since each conductive layer is formed extremely thin, an extremely small voltage is required to achieve maximum elongation.

This piezoelectric element block 34 is electrically connected to the electrode on the substrate 1 through a conductive agent. Although there are various conduction methods, Ag brazing material, conductive paste, or conductive adhesive is generally used. Also, a metal bowl may be pressed between the substrate and the piezoelectric element. The conductive space does not need to be the entire electrode surface, it is sufficient that a certain portion is reliably conductive. However, as mentioned above, since the piezoelectric element block 34 is used by cutting, it is necessary to take care to ensure continuity for each array.

Next, in this state, a slit of a predetermined width is made in the direction of the chain line CC' in FIG. 9 using a dicing saw or a wire saw. At this time, cutting is performed to a depth of 10 to 50 μm from the surface of the substrate 1 so that the surface electrode 22 of the substrate 1 is also divided. At this time, the partition block 3 is also cut in the same manner as each array of piezoelectric elements 4 with the same sleeve I and width. Of course, the pitch may be any desired value. For example, if you are making a 300 DP head, it is 15 per side.
At 0DPI, the pitch is 169.3 μm. The housing 2 is installed so as to surround the piezoelectric element 4 thus cut. The housing 2 is strongly abutted or fixed to the opposite end surface of the substrate 1 and each array of piezoelectric elements 4 on the cavity 11 side.

It is desirable that the adhesive used here has as large a Young's modulus as possible.

Next, as shown in FIG. 10, a resin material is injected and filled into the slit spaces of a predetermined width of the piezoelectric element 4, the partition block 3, and the soluble resin 32, which are cut with a wire saw or the like, and hardened to form the row partitions. Form 5. Suitable resin materials include epoxy, silicone, etc., but there is no need to be particular about these as long as the cured film has appropriate hardness, adhesion, and strength. In addition, this resin material also has electrical insulation properties, and the cutting part of the surface electrode 22 of the substrate 1 is also filled, so that the row direction of each array of piezoelectric elements 4 includes the surface of the substrate 1. In other words, it is cut off and electrically insulated.

Next, as shown in FIG.
Cut along the side end surface and make a slit 33 with a width of W.
form. At this time, the row partitions 5 are divided to form cavity partitions b52. The width W of this slit 33 is a desired width necessary for a cavity partition part a51, which will be described later.

At this time 3. ! ! ! Cutting is performed to a depth of 10 to 50 μm from the surface of the plate 1. At this time, the piezoelectric element 4 including the surface of the substrate 1 is in a disconnected state.

Further, as shown in FIG. 12, a resin material is injected and filled into the slit 33 and hardened to form the cavity partition part a51. Suitable resin materials include epoxy, silicone, etc., but there is no need to be particular about these as long as the cured film has appropriate hardness and strength. It also has electrical insulation properties, and is electrically insulated by being cut off in the same way as in the case of the row partitions 5 described above. Accordingly, by forming the row partitions 5 and the cavity partitions a51, the piezoelectric elements 4 are isolated and electrically insulated from the cavity 111 including the surface of the substrate 1 for each array.

=19= In addition, a sludge prevention wall (not shown) is used as a subassembly (not shown) to prevent the resin material for forming the cavity partition part a51 in the slit 33 from flowing out from the slit 33.
Alternatively, it can be made into a jig (not shown) so that it can be used repeatedly.

Next, the electrodes formed on the upper surface of each piezoelectric element 4 are made conductive and the common electrode is taken out. The electrodes on the substrate 1 side and the lower surface of the array of each piezoelectric element 4 are configured as individual lead electrodes, and the upper surface is electrically connected to the common electrode terminal 13 on the substrate 1 side by using, for example, the outer wall of the housing 2. FIG. 13 shows one example, in which a conductive path is formed on the surface of the housing 2 using conductive paste. In the figure, reference numeral 61 denotes a housing surface conductive path, which is electrically connected to the upper surface electrode of the array of piezoelectric elements 4 through a conductive paste 62. Further, the conductive path 61 is electrically connected to the common conductor 4fila of the substrate 2 through a conductive paste 63. There are various methods of electrical connection, such as using a flexible cable or wire bonding.

Next, the nozzle forming section 7 and the nozzle 8 will be explained in detail.

FIG. 14 shows an example of this, in which a frame 16 that is higher than the intended thickness of the nozzle forming part 7 by a dimension E is temporarily attached to the substrate 1 so as to surround the outside of the housing 2, and A material equivalent to the resin material used to form the cavity partition part a of the partition part 5 or 51 is injected and filled up to two sides of the frame 16 and hardened. Next, the frame 16 is removed and ground to the desired thickness of the nozzle forming portion 7 to make it smooth.

Grinding is performed using a surface grinder, lapping machine, or dicing saw. Thereafter, to form the cavity 11, a nozzle 8, which is a hole penetrating the thickness of the nozzle forming part 7, is accurately drilled at a predetermined position directly above the area filled with the soluble resin using a laser or a drill. The accuracy of drilling is as follows: - For example, the holes are drilled in the same manner as the reference hole provided in the substrate 1, or the X-Y end face of the piezoelectric element block 34, etc. when cutting the piezoelectric element 4 into each array. By doing so, the thickness can be reduced to several μm or less. The thickness of the nozzle 7 after formation is about 0.05 to 0.5 mm, and transparent grade resin material is used, and the soluble resin 32 filled to form the cavity 11 is colored. By doing so, the partition block 3, the cavity partition part a51, the cavity partition part b52, and the row partition part 5
Identification of the piezoelectric element 4 and the piezoelectric element 4 can be easily performed using image processing technology or the like. Therefore, it is possible to drill holes in accurate positions without tilting. Further, the frame 16 may be ground at the same time without being removed; in that case, it is necessary to securely bond it to the substrate 1. In this way, the vicinity of the nozzle 8 of the nozzle forming part 7 is surrounded by each partition member and is very strongly supported and adhered or closely attached.
Deformation and peeling will no longer occur, and the row partition part and cavity partition part a in the above-mentioned cutting will no longer occur.
The surface portions of the substrate corresponding to 51 and b52 are reliably cut to the point where the substrate material is exposed, so the adhesion or adhesion strength with each partition member is high, and the adhesion or adhesion strength between each partition member is also high. Also, each array of piezoelectric elements 4 is completely isolated and electrically insulated from the cavity 11, and each cavity 11 is separated and independent. Therefore, ink or the like does not enter each piezoelectric element 4, there is no electrical short circuit, and the influence of the dynamic pressure exerted by the piezoelectric element 4 on adjacent nozzles is small.

Next, the soluble resin 32 filled to form the cavity 11 is removed. If it is a positive type photoresist, it is suitable to remove it with acetone or aqueous ammonia, and if it is a negative type photoresist, it is removed by heating and spraying a strong acid type aqueous solution. Thereby, a cavity 11 can be formed as shown in FIG. 12.

This figure shows that in FIG. 9, the partition block 3 is also cut at the same time as the piezoelectric element 4, and as shown in FIG. It is formed by injecting and filling a resin material into a slit 33 having a width of the required width W as the planned space for the blocking member, and then hardening it, and then removing the soluble resin 32. This is an example of a state in which .

-23 = In this embodiment, the cavity 11 is sandwiched between the partition blocks 3.
Although the method in which the nozzle openings are opposed to each other has been described, it is of course possible to have a single row of nozzle openings, or it is also easy to have multiple rows of nozzle openings. Further, in the print head configured in this way, when an electric signal is applied to the piezoelectric element 4 via the cable 12, the piezoelectric element 4. 4. 4.・・・・・・
extends in the stacking direction of the electrodes, so the free end of the piezoelectric element pushes out the ink on the front toward the partition block 3. As a result, the ink rushes into the nozzle opening 8 under dynamic pressure, becomes an ink droplet, flies in the external space, and forms a dot on the printing paper.

When the electric signal is no longer applied, the piezoelectric element contracts to its original state, and ink flows into the gap between the partition block 3 and the piezoelectric element 4 in preparation for the generation of the next ink droplet.

By the way, in this embodiment, the cavity partition part a51 as the cut-off insulating part has been described as being formed after the formation of the other partition parts, but the desired slits are formed and the cavity partition part a51 is formed integrally with the other partition parts at the same time. Formation=24- It may also be formed integrally with the nozzle forming portion, and the method is not limited thereto. FIG. 15 is a diagram showing an example of another embodiment of forming the partition portions, in which all the partition portions are integrally formed.

Furthermore, in this embodiment, the nozzle forming part is described as being formed with a material that is injected and cured, but the method is not limited to this method. It may be adhered to the position with adhesive or the like. Furthermore, FIG. 16 is a diagram showing a second embodiment in which the resin material 5 serving as the partition member of each cavity does not extend to the partition block 3. Since the first embodiment is a high-density head, there is a problem of crosstalk.

This embodiment is relatively effective when the density of adjacent nozzle openings is not high, and is sufficiently practical. In the figure, the nozzle forming portion 7 is seen through, and the space between the piezoelectric elements and between the piezoelectric element and the cavity is filled with resin-based materials 5 and 51. In the figure, 3 is a partition block that partitions the piezoelectric element rows. In the case of this embodiment, the partition block 3 and the piezoelectric element block 34 are closely adhered, and the dividing slit for each piezoelectric element 4 and the slit on the cavity side end face of the piezoelectric element 4 are filled with the resin material 5, and then A cavity 9o can be formed by making a slit like the void 31 in FIG. 7. 91 in FIG. 16 is the gap formed in this manner. Further, the partition block 3 may be used as the partition block 3 by extending a layer that does not contribute to the piezoelectric action of the piezoelectric element block 34 and cutting that layer later.

〔Effect of the invention〕

As described above, according to the configuration of the present invention, by providing the blocking partition member, that is, the cavity partition part a, between the ink reservoir, that is, the cavity, and the piezoelectric element, ink is prevented from entering the piezoelectric element side. Additives added to improve the performance of ink on recording paper, such as surfactants, can prevent corrosion of the electrodes on the surface of the piezoelectric element, and can also prevent short circuits caused by conductive ink, etc., and improve the ink's compatibility. This has the effect of realizing a highly reliable on-demand inkjet print head. In addition, since each partition member is made of a resin material that is injected and hardened, it can be integrally formed at the same time or by extending it, and the strength of each can be increased, making it easy to use on-demand type with high precision and no deformation. This has the effect of realizing an inkjet print head. Furthermore, by extending the row partitions, the cavities can be partitioned into individual piezoelectric elements, which eliminates ink leakage and interference with adjacent cavities, reducing the dynamic pressure of the ink to the nozzles caused by the piezoelectric elements. This has the effect of increasing the ink droplet formation efficiency and increasing the flying force. Furthermore, by utilizing the vibration in the d33 direction of the laminated piezoelectric element, it is possible to generate ink droplets with sufficient flying force at a low voltage. Furthermore, the method of the present invention allows for the production of multiple inkjet printheads at the same time, making it possible to manufacture very inexpensive inkjet printheads.It is also a method that is superior in high density and high reliability, resulting in miniaturization and low cost. 1-=27- at the same time, and is an extremely effective invention.

[Brief explanation of the drawing]

1 to 5 show the structure of a first type of on-demand inkjet print head according to the present invention, and FIG. 1 is an external perspective view. Figure 2 is a plan view. FIG. 3 is a cross-sectional view of the drive section taken along the line AA' in FIG. 2 and centered on the nozzle section. FIG. 4 is a sectional view taken along the line BB' in FIG. 2 and centered around the partition. FIG. 5 is a plan view with the nozzle forming part provided with the nozzle in FIG. 2 removed. 6 to 14 are diagrams related to the manufacturing process according to the present invention, and FIG. 6 is a detailed diagram of the substrate. FIG. 7 is a diagram showing a partition block and a piezoelectric element block adhered to a substrate. FIG. 8(a) is a state diagram of a sintered body of a piezoelectric element block. FIG. 8(b) is a state diagram of the piezoelectric element block with external electrodes attached. FIG. 9 is a state diagram of dividing and cutting a piezoelectric element block. Figure 10 shows bacteria forming the row partitions. FIG. 11 is a diagram showing the formation of the cavity partition. FIG. 12 is a diagram showing the formation of the cavity partition a and the cavity 11. FIG. 13 is a diagram showing an example of a state in which the common electrode is taken out. FIG. 14 is a diagram showing an example of a nozzle forming portion and a state in which the nozzle is formed. FIG. 15 is a diagram showing an example of another embodiment of forming a partition portion. FIG. 16 is a diagram showing a second embodiment in which the partition members of each cavity are not extended. 1... Substrate 2... Housing 3... Partition block 4... Piezoelectric element 5... Row partition part 7... Nozzle forming member 8... Nozzle 11.90... Cavity 12. ... Cable 51 ... Cavity partition part a 52 ... Cavity partition part A and above

Claims (8)

[Claims] (1) A piezoelectric plate made of a piezoelectric material and a conductive material is cut to a predetermined width, one end is fixed to or in contact with a base, and the other end is arranged as a free end, and a row of piezoelectric elements is arranged opposite to the free end. an opposing partition member disposed to provide a space for forming an ink reservoir; and a blocking member disposed on the free end side of the space so as to face the opposing partition member and isolate the space from the free end. An on-demand inkjet print head comprising: a partition member; a nozzle member having a nozzle opening facing the space; and a row partition member disposed between the rows of piezoelectric elements. (2) The on-demand inkjet print head according to claim 1, wherein the blocking partition member extends from the row partitioning member. (3) Claim 1 characterized in that the row partition member extends so as to partition the space for each piezoelectric element.
On-demand inkjet printhead as described. (4) The on-demand inkjet print head according to claim 1, wherein the shielding partition member is made of an electrically insulating material. (5) The on-demand inkjet print head according to claim 2, wherein the column partition member is made of an electrically insulating material. (6) The on-demand inkjet print head according to claim 1 or 4, wherein the blocking partition member is made of a material that is injected and cured. (7) The on-demand inkjet print head according to claim 2, wherein the column partition member is made of a material that is injected and cured. (8) The on-demand inkjet print head according to claim 1, wherein the piezoelectric plate is formed by laminating and firing paste-like piezoelectric material and conductive material alternately in layers.