JP4082020B2 - Method for producing shear mode ink jet head - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a shear mode ink jet head suitable for high-speed recording and advantageous for mass production.
[0002]
[Prior art]
As one of drop-on-demand ink jet printing apparatuses, the shear mode type printers described in JP-A-63-252750, JP-A-6-234212-234216, etc. can be reduced in size and speed. Known to be advantageous.
[0003]
This utilizes the piezoelectric thickness slip deformation of the partition wall of the ink channel formed in the piezoelectric ceramic. First, a pressure is applied to expand the ink channel volume to replenish the ink into the channel, and then the channel volume. Ink droplets are ejected from the nozzles by applying a pressure that reduces the pressure.
[0004]
At this time, since the pressure applied to eject the ink remains and vibrates after the ink is ejected, the ink pressure in the nozzle fluctuates and the ink meniscus vibrates. When this vibration is repeated several times, the vibration is gradually attenuated and the next discharge becomes possible.
[0005]
FIG. 1 is a partial cross-sectional perspective view showing an example of the configuration of such a shear mode type ink jet head. In the figure, 1 is a piezoelectric ceramic substrate, 2 is a nozzle plate, 3 is a nozzle, 4 is an ink channel, 5 is a side wall, 6 is a cover plate, and 7 is an ink supply unit provided in communication with each ink channel. .
[0006]
The piezoelectric ceramic substrate 1 is cut by a diamond blade or the like, and a plurality of grooves (ink channels) 4 are all formed in parallel with the same shape, and the side wall 5 which is the side surface of the groove 4 is divided in the direction of the arrow. . The depth of the groove 4 gradually becomes shallower as one end face 11 of the piezoelectric ceramic substrate is approached, and a shallow groove 9 is formed in the vicinity of the end face 11. On the inner surface of the groove 4, metal electrodes 8 are formed on the upper half of both side surfaces by sputtering or the like. An introduction electrode 10 is formed on the inner surface of the shallow groove 9 on the side surface and bottom surface thereof by sputtering or the like, and the metal electrode 8 and the introduction electrode 10 communicate with each other.
[0007]
The cover plate 6 is formed of a ceramic material or a resin material, and an ink supply unit 7 is formed by grinding or cutting. The surface of the piezoelectric ceramic substrate 1 where the groove 4 is processed and the surface of the cover plate 6 where the ink supply unit 7 is processed are bonded using an epoxy adhesive or the like, and the upper surface of the groove 4 is covered with the cover plate 6. Covered with ink channels.
[0008]
A nozzle plate 2 provided with a nozzle 3 at a position corresponding to the position of each ink channel 4 is bonded to the end surfaces of the piezoelectric ceramic substrate 1 and the cover plate 6. The nozzle plate is formed of a plastic plate such as polyalkylene terephthalate such as PET, polyimide, polyetherimide, polyether ketone, polyethersulfone, polycarbonate, cellulose acetate, or a metal plate such as stainless steel.
[0009]
A substrate 12 having a conductive layer pattern 13 formed at a position corresponding to the position of each ink channel 4 is adhered to the surface of the piezoelectric ceramic substrate 1 opposite to the processed side of the groove 4 by an epoxy adhesive or the like. The conductive layer pattern 13 and the introduction electrode 10 in the shallow groove 9 are connected by a wire bonding conductor 14.
[0010]
FIG. 2 is a diagram for explaining the operation principle of ink ejection. In ejecting ink from the ink channel 4 in the figure, a positive drive voltage is applied to the metal electrodes 8a and 8b, and the metal electrodes 8c and 8d are grounded. As shown in FIG. 2B, a driving electric field in the direction of the arrow is generated on each side wall 5. Since the direction of the driving electric field is orthogonal to the direction of division of the piezoelectric ceramic substrate, each side wall 5 is rapidly deformed in the inner direction of the ink channel 4 in this case due to the piezoelectric thickness slip effect. Due to this deformation, the volume of the ink channel 4 decreases, the ink pressure rapidly increases, a pressure wave is generated, and ink droplets are ejected from the nozzle 3 communicating with the ink channel 4.
[0011]
When the application of the drive voltage is stopped, each side wall 5 gradually returns to the position before deformation (FIG. 2A), so that the ink pressure in the ink channel 4 gradually decreases. Then, ink is supplied to the ink channel 4 from an ink supply source (tank) (not shown) through the ink supply unit 7.
[0012]
[Problems to be solved by the invention]
As described above, since the shear mode type ink jet head uses the piezoelectric thickness slip deformation of the side wall 5 of the ink channel 4 formed on the piezoelectric ceramic substrate 1, the cover plate 6 has a strength against deformation and the like. For this reason, it is preferably formed of a ceramic material, and the ink supply unit 7 is formed by grinding or cutting.
[0013]
Actually, the cover plate is less than 1 mm, and it is very difficult to process the ceramic thin plate, and the fact that the processing is performed one by one has not yet been mass-produced. Further, if the hole peripheral surface of the ink supply unit 7 has irregularities, the accuracy of the individual lengths of the ink channels 4 may vary, and the ink ejection may be bent. In addition, the corners of the holes inevitably have roundness (R), which may cause problems with uniform ink supply to each ink channel.
[0014]
The present invention has been made in view of the above circumstances, and the purpose thereof is to realize stable high-speed ejection by increasing the processing accuracy of the ink supply portion of the shear mode type ink jet head connected to each ink channel. An object of the present invention is to provide a cover plate that can be used, and to enable mass production of the inkjet head.
[0015]
[Means for Solving the Problems]
The above object of the present invention is to
Processing a recess extending in the thickness direction of the plate-shaped cover plate to be produced on one surface of the first rectangular block made of ceramic;
Affixing the first rectangular block having a concave portion to a ceramic second rectangular block with the concave portion facing the second rectangular block using an adhesive ; and
A step of obtaining a cover plate sliced in a plate shape having a cavity by the recess by slicing the second rectangular block to which the first rectangular block is pasted in a cross section including the recess in a direction crossing the recess. When,
Bonding the sliced cover plate to a piezoelectric ceramic substrate having a plurality of ink channels grooved , with the sliced surface facing the grooved surface; and
A method for producing a shear mode type ink jet head, comprising:
Is achieved.
[0016]
In other words, the present inventor is difficult to drill the ink supply part in the thin plate and it is difficult to improve the accuracy, but it is difficult to process by forming the ink introduction port in advance with a thick block and cutting out the cover plate by slicing. In addition, the present inventors have found that productivity can be improved as well as the present invention.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of production will be described, but the present invention is not limited thereto.
[0018]
First, as shown in FIG. 3, the first rectangular block 31 in which the concave portions 32 are formed on both sides of the second rectangular block 33 by using a dicing saw, a diamond blade, or the like is put together using an epoxy adhesive or the like. Adhere so that there is no gap on the surface. An adhesive can be applied by dispenser application, screen application, and the like, and can be adhered by pressing and heating, and the protruding adhesive can be removed by grinding, plasma treatment, or the like. Furthermore, a glue guard can be provided at a position that does not impair the sealing performance. In order to uniformly apply the adhesive, the mating surfaces may be surface-treated by UV treatment, plasma treatment or the like, or a primer layer may be formed.
[0019]
Next, as shown in FIG. 4, it is sliced with a wire saw or the like, and the surface on the side to be bonded to the piezoelectric ceramic substrate is smoothly finished by lapping or the like to obtain cover plate members 41 for two heads.
[0020]
FIG. 5 shows a model diagram of a process of bonding the cover plate member 41 to the piezoelectric ceramic substrate 51 in which the ink channel 4 is grooved and the nozzle forming surface 52 is not cut, and the ink channel portion is shown in cross section. In FIG. 3, the perforation 53 for the ink introduction portion formed by bonding the recess 32 and the rectangular blocks is aligned with the shallow groove 9 portion of the ink channel, and the cover plate member 41 is similar to the bonding between the rectangular blocks. Pasting is performed. Next, cutting is performed at the cutting position indicated by the line AA ′ to obtain the nozzle forming surface 52 and two head members are obtained.
[0021]
【The invention's effect】
According to the present invention, a cover plate having a perforation for an ink supply unit configured to communicate with a plurality of ink channels, the processed surface and the second rectangular block of the first rectangular block having a rectangular recess processed on one surface Therefore, it is possible to improve the roundness of the corners of the ink supply part, to improve the processing accuracy, and to form the second rectangular part in which the concave part is processed. In some cases, no adhesive is applied to the block surface, so that it is possible to prevent the ink from being bent, and it is possible to supply the ink evenly to each ink channel, thereby realizing stable high-speed ejection.
[0022]
In addition, processability is improved and it is easy to deal with mass production.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional perspective view showing an example of the configuration of a shear mode type ink jet head.
FIG. 2 is a diagram illustrating an operation principle of ink ejection.
FIG. 3 is a model diagram illustrating a process according to the present invention.
FIG. 4 is a model diagram showing cutout of a cover plate member according to the present invention.
FIG. 5 is a model diagram showing bonding between a piezoelectric ceramic substrate and a cover plate member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Piezoelectric ceramic substrate 2 Nozzle plate 3 Nozzle 4 Ink channel 5 Side wall 6 Cover plate 7 Ink supply part 8 Metal electrode 9 Shallow groove 10 Introduction electrode

Claims (7)

Processing a recess extending in the thickness direction of the plate-shaped cover plate to be produced on one surface of the first rectangular block made of ceramic;
Affixing the first rectangular block having a concave portion to a ceramic second rectangular block with the concave portion facing the second rectangular block using an adhesive ; and
A step of obtaining a cover plate sliced in a plate shape having a cavity by the recess by slicing the second rectangular block to which the first rectangular block is pasted in a cross section including the recess in a direction crossing the recess. When,
Bonding the sliced cover plate to a piezoelectric ceramic substrate having a plurality of ink channels grooved , with the sliced surface facing the grooved surface; and
A method for producing a shear mode ink jet head, comprising: 2. The method of manufacturing a shear mode type ink jet head according to claim 1, wherein the concave portion is a perforation for an ink supply unit that communicates with a plurality of ink channels and is provided in common to the plurality of ink channels . The affixing step includes affixing the two first rectangular blocks having recesses to both sides of the ceramic second rectangular block using the adhesive with the recesses on the second rectangular block side. ,
The step of obtaining the cover plate includes slicing the second rectangular block to which the two first rectangular blocks are pasted in a cross-section including the concave portion in a direction crossing the concave portion, thereby providing a cavity by the concave portion on both sides. To obtain a cover plate sliced into a plate shape,
The method for producing a shear mode type ink jet head according to claim 1, further comprising a step of cutting the piezoelectric ceramic substrate to which the cover plate is bonded between two recesses. The step of obtaining the cover plate includes slicing the second rectangular block to which the first rectangular block is pasted at a predetermined pitch in a direction crossing the concave portion to obtain a plurality of cover plates having both sides sliced. The method for producing a shear mode type ink jet head according to any one of claims 1 to 3. Between the step of obtaining the cover plate and the step of bonding, the step of lapping the surface of the cover plate to be bonded to the piezoelectric ceramic substrate,
In the bonding step, a cover plate sliced in a plate shape is bonded to a piezoelectric ceramic substrate in which a plurality of ink channels are grooved, with the lapped surface and the grooved surface facing each other. The method for producing a shear mode type ink jet head according to any one of claims 1 to 4, wherein: The method for producing a shear mode type ink jet head according to claim 1, further comprising a step of removing the adhesive protruding from the adhesive surface after the attaching step. The method of manufacturing a shear mode type ink jet head according to claim 1, wherein the step of processing the recess includes processing the recess using a dicing saw or a diamond blade.

Images