JPH11227200A - Head for forming fine ink droplets and method of manufacturing the same - Google Patents

Abstract

(57) Abstract: Provided is a head for forming fine droplets of ink which can reduce interference between driving units corresponding to dots and improve printing characteristics. SOLUTION: There are provided a plurality of ink chambers each provided with a hole for ejecting a fine droplet of ink. A portion of the wall defining each ink chamber can be deformed to change the volume of the corresponding ink chamber. A first electrode layer, a piezoelectric layer, a second electrode layer, a high-stiffness layer, and a support layer are sequentially stacked from the facing surface side so as to face the deformed portions of the walls of the plurality of ink chambers. I have. A plurality of grooves reaching the position deeper than the high-rigidity layer are formed on the opposing surface side, and the grooves separate the laminated structure from the first electrode layer to the high-rigidity layer. Each of the separated individual laminated portions is arranged so as to correspond to each of the ink chambers. By deforming the piezoelectric layer of each individual laminated portion, a part of the wall of the corresponding ink chamber is deformed to change the volume of the ink chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head for forming fine droplets of ink and a method of manufacturing the same, and more particularly to a head used for a printer which performs printing by flying fine droplets of ink on paper.

[0002]

2. Description of the Related Art As an ink jetting method of an ink jet printer which performs printing by flying fine droplets of ink, a bubble jet method using a heating element and an impact method (piezoelectric method) using a piezoelectric material are known. I have. The piezoelectric method is a method in which the volume of an ink chamber corresponding to a dot is reduced by deformation of a piezoelectric body, and fine droplets of ink fly from a hole provided in the ink chamber. A plurality of ink chambers are linearly arranged, and a drive unit including a piezoelectric body is arranged corresponding to each ink chamber.

If the piezoelectric bodies of a plurality of driving units are connected in parallel, the displacement characteristics of the piezoelectric bodies may be affected by the interaction between the piezoelectric bodies, and the flying characteristics of the ink may be reduced. To reduce this interaction, grooves are provided between adjacent piezoelectric bodies.

[0004]

By forming a groove between piezoelectric bodies adjacent to each other, it is possible to reduce interference between the driving units, but this is not sufficient. In order to improve the printing characteristics, it is necessary to further reduce the interference between the driving units.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a head for forming fine droplets of ink which can reduce interference between driving units corresponding to dots and improve printing characteristics.

Another object of the present invention is to provide a method of manufacturing a head for forming fine droplets of ink, which can reduce interference between driving units corresponding to dots and improve printing characteristics.

[0007]

According to one aspect of the present invention, there are provided a plurality of ink chambers each provided with a hole for ejecting a fine droplet of ink, and one of the walls defining the ink chamber. The portion is deformed, the plurality of ink chambers capable of changing the volume of the corresponding ink chamber, and arranged to face a deformed portion of the wall of the plurality of ink chambers,
A first electrode layer, a piezoelectric layer, a second electrode layer, a high-stiffness layer made of a material having higher rigidity than the piezoelectric layer, and a support layer in this order from the facing surface side facing the deformed portion. A plurality of grooves reaching the position deeper than the high-rigidity layer are formed on the facing surface side, and individual laminated portions separated from each other by the grooves are provided. Are arranged so as to correspond to each of them, and by deforming the piezoelectric layer of each individual laminated portion, a part of the wall of the corresponding ink chamber is deformed to change the volume of the ink chamber. A head for forming fine droplets of ink having a piezoelectric laminated member is provided.

[0008] The piezoelectric layer of each individual laminated portion generates piezoelectric strain and reduces the volume of the corresponding ink chamber. Ink in the ink chamber flies outside through the holes. Since the high rigidity layer is arranged in each individual laminated portion, interference of distortion between the individual laminated portions can be reduced.

According to another aspect of the present invention, on one surface of a piezoelectric film formed by dispersing a powder of a piezoelectric material in a binder resin, a material having higher rigidity than the material of the piezoelectric film is formed. A step of preparing a plurality of piezoelectric films with electrodes on which electrode layers are formed, and laminating and bonding at least three piezoelectric films with electrodes so that the surface on the electrode layer side faces in the same direction; And forming a groove in the laminated film from the surface on the electrode layer side thereof to be parallel to each other and reaching a position deeper than at least the third electrode layer, and at least separated from each other by the groove. Forming a plurality of individual laminated portions including three electrode layers, coupling an ink chamber whose volume is changed by deformation of each individual laminated portion to the top of each of the individual laminated portions, Two layers on the top side of each of the laminates Forming a power supply line for applying a voltage between the electrode layers, wherein the electrode layer at the deepest position of the individual laminated portion forms the power supply line so as to maintain an insulation state with the power supply line. And a method for manufacturing a head for forming fine droplets of ink.

[0010] The electrode layer, which is kept insulated from the power supply wiring, acts as a highly rigid layer. For this reason, it is possible to reduce distortion interference between the individual laminated portions.

[0011]

FIG. 1 is a sectional view of an ink jet printer head according to an embodiment of the present invention. FIG.
FIG. 1A is a cross-sectional view perpendicular to the ink flight direction, and FIG. 1B is a cross-sectional view taken along a dashed-dotted line B1-B1 in FIG.

As shown in FIG. 1A, an ink jet printer head is configured by bonding a piezoelectric laminated member 1 and a pressure chamber plate 2 with an adhesive layer 3. The pressure chamber plate 2 is formed of a highly rigid material such as stainless steel or resin. The adhesive layer 3 is, for example, a dry film. A plurality of groove-shaped recesses 4 are formed on the opposing surface of the pressure chamber plate 2, and the ink chambers 5 are defined by the recesses 4 and the adhesive layer 3. By pressing the adhesive layer 3 defining each ink chamber 5 toward the ink chamber 5 to deform the adhesive layer 3,
The volume of the corresponding ink chamber 5 can be changed.

In a region corresponding to the ink chamber 5 of the piezoelectric laminated member 1, the piezoelectric layer 8 is formed from the side facing the pressure chamber plate 2.
A, first electrode layer 9A, piezoelectric layer 8B, second electrode layer 9
B, piezoelectric layer 8C, third electrode layer 9C, piezoelectric layer 8D,
The high-rigid layer 10A, the piezoelectric layer 8E, the high-rigid layer 10B, the piezoelectric layer 8F, the high-rigid layer 10C, and the support layer 11 are laminated in this order.

Each of the piezoelectric layers 8A to 8F and the support layer 11
For example, piezoelectric ceramic in binder resin containing plasticizer
Green sheet in which powder is dispersed
Or a plurality of films. One green sea
The thickness of the sheet is 50 to 100 μm. Piezoelectric ceramic
Powder is, for example, 0.5 Pb (Ni_1/3Nb_2/3) O _Three
-0.35PbTiO_Three-0.15PbZrO_Three(PN
N), and the binder resin is, for example, polyvinyl butyral.
And the plasticizer is, for example, dibutyl phthalate.
You.

The electrode layers 9A to 9C and the high-rigidity layers 10A to 10A
10C is formed by, for example, a printing method using an AgPd paste.

A plurality of grooves 15 are formed on the surface of the piezoelectric laminated member 1 on the side of the adhesive layer 3 so as to reach a position deeper than the high rigidity layer 10B. The groove 15 divides the laminated structure from the piezoelectric layer 8A to the high-rigidity layer 10B into a plurality of individual laminated portions 16. Each individual laminating part 16 is arranged so as to correspond to each of the ink chambers 5.

When a voltage is applied between the second electrode layer 9B and the first and third electrode layers 9A and 9C above and below the second electrode layer 9B, piezoelectric strain occurs in the piezoelectric layers 8B and 8C. Each individual laminated part 1
By deforming the 6 piezoelectric layers 8B and 8C, the adhesive layer 3 defining the corresponding ink chamber 5 can be deformed, and the volume of the ink chamber 5 can be changed.

As shown in FIG. 1B, the first electrode layer 9
A and the third electrode layer 9C extend to the left end surface (front end surface) of the piezoelectric laminated member 1 in the figure, and the second electrode layer 9B
Extends to the right end surface (rear end surface) in the figure. Both ends of the high rigidity layers 10A to 10C are not exposed on the front end face and the rear end face.

A first power supply wiring layer 20 is formed on the front end face of the piezoelectric laminated member 1, and a second power supply wiring layer 21 is formed on the rear end face. First and third electrode layers 9A
And 9C are both connected to a first power supply wiring layer 20, and the second electrode layer 9B is connected to a second power supply wiring layer 21.

The groove 25 provided in the pressure chamber plate 2 and the adhesive layer 3
Thus, the common ink path 26 is defined. The ink common path 26 is arranged on the rear end face side of each ink chamber 5 and extends in a direction perpendicular to the paper surface of FIG. Each ink chamber 5
Are connected to an ink common path 26 via an ink supply path 27 provided for each ink chamber. Common ink path 26
When the ink is introduced into the ink chamber 5, the ink is introduced into each ink chamber 5 through the ink supply path 27.

The front end face side of the ink chamber 5 is closed by a nozzle plate 22. The nozzle plate 22 has nozzles 23 corresponding to the respective ink chambers 5. Individual laminated part 16
When the volume of the ink chamber 5 is reduced by deforming the ink, the ink in the ink chamber 5 is pushed to the outside through the nozzles 23 and flies as droplets. Since the ink supply path 27 has a large flow path resistance, the ink in the ink chamber 5 does not flow backward to the ink common path 26 side.

In the embodiment shown in FIG. 1, high rigid layers 10A and 10B are inserted at the bottom of each individual laminated portion 16. The high rigidity layers 10A and 10B have higher rigidity than the piezoelectric layers 8A to 8F. The high rigidity layer can reduce the influence on one individual laminated portion 16 when one individual laminated portion 16 is deformed.

Further, the high-rigidity layer 10C is arranged at a position deeper than the groove 15, and is not separated by the groove 15. That is, each individual laminated portion 16 has a configuration mounted on one high-rigid layer 10C. With the high rigidity layer 10C, interference between the individual laminated portions 16 can be reduced.

The high-rigidity layers 10A to 10C are formed by electrode layers 9A to 9C.
9C, the electrode layers 9A to 9C are formed.
With the same technology as the technology for forming 9C, the high rigidity layers 10A to
10C can be formed. As in the above example,
When the high-rigid layers 10A to 10C are formed of a conductive material, each of the high-rigid layers 10A to 10C is connected to the electrode layers 9A to 9C.
It is preferable to be electrically insulated from C.

In the above embodiment, the high rigidity layers 10A to 10C
Is formed of the same AgPd as the material of the electrode layers 9A to 9C, but both may be formed of Pt,
The high-rigid layers 10A to 10C may be formed of another material having higher rigidity than the piezoelectric layers 8A to 8F.

Next, a method of manufacturing the ink jet printer head shown in FIG. 1 will be described with reference to FIGS.

FIG. 2A shows one green sheet (piezoelectric film) 30 having an AgPd layer. The green sheet is a film having a thickness of 50 to 100 μm in which piezoelectric ceramic powder is dispersed in a binder resin containing a plasticizer. The material of the piezoelectric ceramic powder is PNN, the binder resin is polyvinyl butyral, and the plasticizer is dibutyl phthalate.

On one surface of the green sheet 30, A
The AgPd layer 31 is printed by a printing method using a gPd paste.
To form In FIG. 2A, one green sheet 3
0 is divided into four regions, and the AgPd layer 31 is formed in each region.
Is formed. AgP shown in FIG.
A plurality of green sheets 30 having a d-layer and a plurality of green sheets having no AgPd layer are prepared.

As shown in FIG. 2B, the green sheets 30A to 30G with the AgPd layer and the green sheets 40A to 40C without the AgPd layer are superposed in the order shown. The green sheets 30A, 40A, and 40B correspond to the piezoelectric layer 8A shown in FIG. 1A, the green sheets 30B to 30F correspond to the piezoelectric layers 8B to 8F, respectively, and the green sheets 30G and 40C correspond to the support layer. It corresponds to 11. The AgPd layers 31 printed on the surfaces of the green sheets 30B to 30G respectively correspond to the first electrode layers 9.
A, second electrode layer 9B, third electrode layer 9C, high rigidity layer 1
It corresponds to 0A to 10C.

Heat to a temperature of 60 to 120 ° C. and a pressure of 30
グ リ ー ン 50 MPa is applied to bond the green sheets.
After bonding, the temperature is set to 1100 ° C. in the atmosphere, and firing is performed for 4 hours.

As shown in FIG. 2C, a piezoelectric laminate 41 in which green sheets are laminated is formed. The periphery of the piezoelectric laminate 41 is cut and further divided into regions corresponding to the respective AgPd layers 31. The AgPd layer 31 exposed on the uppermost layer of the separated piezoelectric laminate 41 is polished and removed.

As shown in FIG. 3, the grooves 15 are formed using a dicing saw, and the piezoelectric laminated member 1 is obtained. Groove 15
Deeper than the AgPd layer 31 on the green sheet 30F,
And it reaches a position shallower than the AgPd layer 31 on the green sheet 30G, and separates the individual laminated portions 16 from each other. In addition, only the first and third electrode layers 9A and 9C among the electrode layers 9A to 9C appear on the front end face of the piezoelectric laminated member 1, and the second electrode layer 9B is the rear end face of the piezoelectric laminated member 1. Appears in.

After forming the groove 15, the first and second power supply wiring layers 20 and 21 shown in FIG. 1B are formed on the front end face and the rear end face, respectively. Power supply wiring layers 20 and 21
Is formed by a laminated structure in which, for example, Cr / Ni / Au is deposited in this order. Each layer is deposited by vapor deposition or sputtering. In addition, power supply wiring layers 20 and 2
1 may be formed, for example, by using Ag paste and baking at a temperature of about 600 ° C.

A pressure chamber plate 2 shown in FIGS. 1A and 1B is fixed on the upper surface of the piezoelectric laminated member 1 via an adhesive layer 3. The nozzle plate 22 shown in FIG. 1B is fixed to the front end face side of the ink chamber 5.

In the above embodiment, the three AgPd layers on the top side of the individual laminated portions 16 shown in FIG.
The case of using as A to 9C has been described. Other AgPd
Although the layer may be used as an electrode layer, it is preferable to use the AgPd layer closest to the top as the electrode layer in order to reduce interference between the individual laminated portions 16. FIG.
(A) shows a case where three AgPd layers are used as electrode layers, but at least two AgPd layers may be used as electrode layers. The preferred number of AgPd layers used as electrode layers is determined by the amount of piezoelectric displacement suitable for causing ink to fly from the ink chamber 5, and may be three or more.

In the above embodiment, the case where the two high-rigidity layers 10A and 10B are inserted into the bottom of the individual laminated portion 16 has been described. The number of layers may be three or more. Groove 1
Although the case where one layer of the non-separable high-rigid layer 10C is arranged by 5 has been described, two or more non-separated high-rigid layers may be arranged.

The present invention has been described in connection with the preferred embodiments.
The present invention is not limited to these. For example, it will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

[0038]

As described above, according to the present invention,
Reduces interference between piezoelectric laminates by inserting a highly rigid layer at the bottom of each piezoelectric laminate of an inkjet printer head that uses the displacement of the piezoelectric laminate provided for dots to fly ink. Can be done. Since interference between the piezoelectric laminated portions can be reduced, high-quality printing can be performed.

[Brief description of the drawings]

FIG. 1 is a sectional view of an inkjet printer head according to an embodiment of the present invention.

FIG. 2 is a perspective view of a green sheet, a perspective view showing a lamination relationship of the green sheets, and a perspective view of a piezoelectric laminate to which a plurality of green sheets are adhered, for explaining a method of manufacturing the ink jet printer head shown in FIG. is there.

FIG. 3 is a perspective view of a piezoelectric laminated member of the inkjet printer head shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric laminated member 2 Pressure chamber plate 3 Adhesive layer 4 Depression 5 Ink chamber 8A-8F Piezoelectric layer 9A-9C Electrode layer 10A-10C High rigidity layer 11 Support layer 15 Groove 16 Individual lamination part 20, 21 Power supply wiring layer 22 Nozzle Plate 23 Nozzle 25 Groove 26 Common ink path 27 Ink supply path 30A-30G Green sheet with AgPd layer 31 AgPd layer 40A-40C Green sheet without AgPd layer 41 Piezoelectric laminate

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshihiko Imanaka 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Kazuaki Kurihara 4 Ueodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Chome 1-1 Fujitsu Limited

Claims (7)

[Claims] 1. A plurality of ink chambers each having a hole for ejecting a fine droplet of ink, wherein a part of a wall defining the ink chamber is deformed, and a volume of the corresponding ink chamber is changed. The plurality of ink chambers, the first electrodes of which are arranged so as to face a deformable portion of a wall of the plurality of ink chambers, and in order from an opposing surface side facing the deformable portion. A layer, a piezoelectric layer, a second electrode layer, a high-rigid layer made of a material having higher rigidity than the piezoelectric layer, and a support layer, and a position deeper than the high-rigid layer on the facing surface side. A plurality of grooves are formed to reach each other, and individual stacked portions separated from each other by the grooves are provided, and each individual stacked portion is arranged so as to correspond to each of the ink chambers,
A fine liquid of ink having a piezoelectric laminated member configured to deform a part of the wall of the corresponding ink chamber by deforming the piezoelectric layer of each individual laminated portion to change the volume of the ink chamber. Drop forming head. 2. The semiconductor device according to claim 1, further comprising: a space between the high-rigidity layer and the support layer, which is deeper than a depth of the groove.
2. The ink droplet forming head according to claim 1, further comprising another high-rigid layer formed of the same material as the high-rigid layer. 3. The high rigidity layer is arranged in a plurality of layers, and a layer made of the same material as the piezoelectric layer is interposed between the plurality of high rigidity layers. 3. The head for forming fine droplets of the ink according to 2. 4. The first and second electrode layers and the high-rigid layer are formed of the same material, and the high-rigid layer is
The ink droplet forming head according to claim 1, wherein the head is electrically insulated from the first and second electrode layers. 5. The ink droplet forming head according to claim 4, wherein the first and second electrode layers and the high-rigidity layer are formed of AgPd or Pt. 6. An electrode having an electrode layer formed of a material having higher rigidity than the material of the piezoelectric film on one surface of a piezoelectric film formed by dispersing a powder of the piezoelectric material in a binder resin. A step of preparing a plurality of piezoelectric films, a step of laminating and bonding at least three piezoelectric films with electrodes so that the surface on the electrode layer side faces the same direction, and forming a laminated film; In parallel with each other from the surface of the electrode layer side,
Forming a groove reaching a position deeper than at least a third electrode layer, and forming a plurality of individual laminated portions including at least three electrode layers separated from each other by the groove; Coupling an ink chamber, whose volume is changed by deformation of each individual laminated portion, to each of the tops, and applying a voltage between two electrode layers on the top side of each of the individual laminated portions. Forming a power supply line, wherein the electrode layer at the deepest position of the individual laminated portion comprises forming the power supply line so as to maintain an insulating state with the power supply line. Manufacturing method of forming head. 7. In the step of forming the laminated film, at least four piezoelectric films with electrodes are attached to each other, and in the step of forming the individual laminated portion, from a surface on which the groove is formed to an electrode layer at a deepest position. 7. The method according to claim 6, wherein the groove is formed such that the groove does not reach.