JP2009267114A - Laminated piezoelectric ceramic element and manufacturing method of the same - Google Patents

Abstract

An object of the present invention is to provide a multilayer piezoelectric ceramic element that is easy to manufacture, has excellent insulation resistance and does not deteriorate even in a high humidity environment, and a method for manufacturing the same.
A laminate 4 in which a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers are alternately laminated and integrated is provided, and the internal electrode layer serves as a counter electrode and is exposed to a side surface of the laminate 4. Every other electrode layer is covered with an insulating portion, a pair of external electrodes 5 are formed to cover the insulating portion and to be electrically connected to the internal electrode layer, and the external electrodes 5 are exposed on the surface. In the ceramic element 1, an exterior resin layer 8 is formed on the side surfaces and corners of the laminate 4.
[Selection] Figure 1

Description

  The present invention relates to a laminated piezoelectric ceramic element used for a laminated piezoelectric sensor, a laminated piezoelectric actuator, and the like, and a method for manufacturing the same.

  Conventionally, piezoelectric ceramic elements that generate voltage by external stress or generate displacement or force by applying voltage have been put to practical use in pressure sensors, piezoelectric actuators, and the like. In recent years, multilayer piezoelectric ceramic elements have become widespread in order to improve sensor sensitivity and actuator displacement characteristics.

  FIG. 9 is a diagram showing a conventional multilayer piezoelectric ceramic element, FIG. 9A is a top view of the conventional multilayer piezoelectric ceramic element, and FIG. 9B is a diagram of the conventional multilayer piezoelectric ceramic element. It is a perspective view. As shown in FIG. 9, the conventional multilayer piezoelectric ceramic element 1 constitutes a multilayer body 4 in which a plurality of piezoelectric ceramic layers 2 and a plurality of internal electrode layers 3 are alternately laminated. Since the internal electrode layer 3 is disposed on the entire surface of the piezoelectric ceramic layer 2, the end surface of the internal electrode layer 3 is exposed on the side surface of the multilayer body 4. On the pair of opposing surfaces of the laminate 4, insulating portions 6 are provided that cover the exposed internal electrode layer 3 every other layer with an insulating resin or the like. A pair of external electrodes 5 electrically connected to the internal electrode layer 3 is formed so as to cover the insulating portion 6. A lead wire or the like (not shown) for electrical connection with an external device is joined to an appropriate position of the external electrode 5 by soldering or a conductive adhesive. Further, an exterior resin layer 8c is formed on the other opposing surface where the insulating portion 6 and the external electrode 5 are not formed.

  FIG. 10 is an enlarged top view of a corner portion of a conventional multilayer piezoelectric ceramic element. The exterior resin layer 8c is mainly intended to protect against moisture resistance and external stress, and is required to prevent characteristic deterioration and destruction due to humidity and external force. Further, the exterior resin layer 8c is generally formed by applying an exterior resin paste to the exposed side surface of the internal electrode layer 3 of the laminate by a dispenser, screen printing, or the like. However, in such a coating method, the exterior resin paste flows due to surface tension, shrinks during thermosetting, and further, due to bubbles in the exterior resin, entrainment of bubbles in the coating process, etc. As shown, the outer resin layer 8c is extremely thin at the corners of the laminate, or the outer resin layer 8c is absent and the internal electrode layer 3 is exposed.

  On the other hand, in recent years, multilayer piezoelectric actuators have been further expanded in applications that are small and require a large amount of displacement. With the expansion of applications, multilayer piezoelectric ceramic elements are increasingly used in high-humidity environments and are used by soldering lead wires or flexible cables to external electrodes or joining them with conductive adhesives. . When used in this way, countermeasures against degradation of piezoelectric properties such as insulation resistance and reliability of multilayer piezoelectric ceramic elements due to solder or conductive adhesive wrapping around corners of multilayer piezoelectric ceramic elements Was necessary.

  In general, the cause of deterioration in piezoelectric properties and reliability such as insulation resistance is included in internal electrodes, external electrodes, solder, and conductive adhesives when a voltage is applied to a laminated piezoelectric ceramic element in a high humidity environment. That is, metal ions (silver ions) move from the negative electrode to the positive electrode to cause an electrical short circuit, so-called silver migration.

  In order to improve the above-described problem, in Patent Document 1, in a multilayer piezoelectric actuator, after connecting a lead wire to an external electrode, an outer periphery is applied to the entire peripheral surface of the multilayer body including the surface on which the external electrode is formed. A structure has been proposed in which an insulating layer is formed by an electrodeposition method at the corner. With this structure, it has become possible to provide a laminated piezoelectric ceramic element having excellent moisture resistance that does not deteriorate the insulation resistance even in a high humidity environment.

JP 2003-347621 A

  Currently, in addition to the multilayer piezoelectric ceramic element in which the lead wire is connected, the demand for a leadless multilayer piezoelectric ceramic element which is a product in a state in which the lead wire or the like is not connected is increasing. In the leadless multilayer piezoelectric ceramic element, the external electrode needs to be exposed on the surface in order to connect the external electrode to an external terminal such as a lead wire or a flexible cable in the final process or at the customer. Further, it is necessary that the exterior resin is not attached to the exposed portion of the external electrode, but is exposed on the surface, and the exterior resin layer is formed only on the side surface where the internal electrode is exposed.

  The exterior of the corner portion of the laminated body by the electrodeposition method of the prior art is a method in which a laminated piezoelectric ceramic element is immersed in an electrodeposition liquid to electrically attach an exterior resin. In this method, it is possible to manufacture a laminated piezoelectric ceramic element having a lead wire, but in a leadless laminated piezoelectric ceramic element, the exterior resin adheres to the external electrode, so that the production is very difficult. It was difficult.

  Therefore, the problem to be solved by the present invention is to provide a multilayer piezoelectric ceramic element excellent in reliability, which is easy to manufacture even in the above-described case, and does not deteriorate the insulation resistance even in a high humidity environment, and a method for manufacturing the same. It is to be.

  In order to solve the above-described problem, according to the present invention, a laminated body in which a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers are alternately stacked and integrated is provided, and the internal electrode layer serves as a counter electrode. The internal electrode layer exposed on the side surface is covered with an insulating portion every other layer, and a pair of external electrodes are formed to cover the insulating portion and to be electrically connected to the internal electrode layer. The external electrode is electrically connected to an external device. The external electrode connecting portion is connected to the external electrode, and the external electrode serving as the external terminal connecting portion is a multilayer piezoelectric ceramic element exposed on the surface, and the laminated layer excluding the exposed external electrode forming portion A laminated piezoelectric ceramic element having an exterior resin layer formed on the side and corners of the body is obtained.

  In addition, according to the present invention, there can be obtained a laminated piezoelectric ceramic element characterized in that the exterior resin layer contains any one selected from a fluorine resin, an epoxy resin, and a silicon resin.

  According to the present invention, there can be obtained a multilayer piezoelectric ceramic element characterized in that the thickness of the exterior resin layer is 10 μm or more and 200 μm or less.

  In addition, according to the present invention, it is provided with a laminated body in which a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers are alternately laminated and integrated, the internal electrode layer serving as a counter electrode, and exposed on the side surface of the laminated body Every other internal electrode layer is covered with an insulating portion, and a pair of external electrodes are formed to cover the insulating portion and to be electrically connected to the internal electrode layer, and the external electrodes are electrically connected to an external device. A method of manufacturing a laminated piezoelectric ceramic element having an external terminal connecting portion and exposing an external electrode serving as the external terminal connecting portion on the surface, the side surface of the laminate excluding the exposed portion of the external electrode, and A method for manufacturing a laminated piezoelectric ceramic element, characterized in that an exterior resin layer is formed at a corner, is obtained.

  According to the present invention, there is further provided a laminate formed by cutting a predetermined number of precursor elements obtained by alternately laminating and integrating a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers, the internal electrode layer Is formed as a counter electrode, and the internal electrode layer exposed on the side surface of the precursor element is covered with an insulating portion every other layer to cover the insulating portion and form a pair of external electrodes that are electrically connected to the internal electrode layer. The precursor element is cut to form the laminate, and the external electrode has an external terminal connection portion that is electrically connected to an external device, and the external electrode serving as the external terminal connection portion is provided on the surface. A method of manufacturing a laminated piezoelectric ceramic element to be exposed, wherein an exterior resin layer is formed on a side surface and a corner of the laminated body excluding the exposed formation portion of the external electrode. Manufacturing method obtained That.

  According to the present invention, the first exterior resin layer is formed on both sides of the external electrode formed on the side surface of the precursor element of the multilayer piezoelectric ceramic element, and then the precursor element is cut to form the laminate. And forming a second exterior resin layer on the cut surface of the precursor element to obtain a method for producing a laminated piezoelectric ceramic element.

  In addition, according to the present invention, there can be obtained a method for producing a multilayer piezoelectric ceramic element, wherein the thickness of the exterior resin layer is 10 μm or more and 200 μm or less.

  The present invention provides a laminated piezoelectric ceramic element in which external electrodes are exposed on the surface, and an exterior resin layer is formed on both sides of the external electrode formed on the laminate, the corners, and the side surfaces where the internal electrodes are exposed. This is a structure that secures the thickness of the exterior resin layer. By adopting this structure, it is possible to provide a highly reliable multilayer piezoelectric ceramic element in which the insulation resistance hardly deteriorates even when solder or conductive adhesive wraps around the corner of the multilayer piezoelectric ceramic element. . In addition, since the external electrodes are exposed on the surface, not only conventional multilayer piezoelectric ceramic elements connected with lead wires but also leadless multilayer piezoelectric ceramic elements can be provided by an easy manufacturing method. Become.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a multilayer piezoelectric ceramic element of the present invention, FIG. 1 (a) is a top view of the multilayer piezoelectric ceramic element of the present invention, and FIG. 1 (b) is a multilayer piezoelectric ceramic element of the present invention. It is a perspective view of a ceramic element. FIG. 2 is a view showing a state before the exterior of the multilayer piezoelectric ceramic element of the present invention.

  As shown in FIGS. 1 and 2, the multilayer piezoelectric ceramic element 1 of the present invention includes a multilayer body 4 in which a plurality of piezoelectric ceramic layers 2 and a plurality of internal electrode layers 3 are alternately stacked. Since the internal electrode layer 3 is disposed on the entire surface of the piezoelectric ceramic layer 2, the end surface of the internal electrode layer 3 is exposed on the side surface of the multilayer body 4. On the pair of opposing surfaces of the laminate 4, insulating portions 6 are provided that cover the exposed internal electrode layer 3 every other layer with an insulating resin or the like. A pair of external electrodes 5 electrically connected to the internal electrode layer 3 is formed so as to cover the insulating portion 6. A first exterior resin layer 8a is formed on both sides of the external electrode 5 formed in the laminate 4, and a second exterior resin layer 8b is formed on the other pair of opposing surfaces where the internal electrode layer 3 is exposed. Is formed. The external electrode 5 is exposed on the surface, and a lead wire, a flexible cable, or the like is joined to an appropriate place of the external electrode 5 according to the application, and an electrical connection with an external device is made. .

  The laminated piezoelectric ceramic element 1 is subjected to polarization treatment, and when a voltage is applied, the piezoelectric ceramic layer 2 has a displacement direction 7a-7b shown in FIG. 2 according to the electric field strength applied to the distance between the internal electrode layers 3. The amount of elongation increases in proportion to the electric field strength.

  Next, a method for manufacturing the multilayer piezoelectric ceramic element of the present invention will be described with reference to the drawings. FIG. 3 is a view showing a part of the precursor element of the multilayer piezoelectric ceramic element of the present invention. A green sheet made of a piezoelectric ceramic material and an electrode paste layer formed by printing an electrode paste on the green sheet are laminated in a predetermined number, and after hot pressing, sintered in a range of 1000 ° C. to 1300 ° C. to be a precursor The body element 9 is produced. In the precursor element 9 after sintering, the green sheet layer before sintering becomes the piezoelectric ceramic layer 2 and the electrode paste layer becomes the internal electrode layer 3. The precursor element 9 is cut into a laminate 4 by being cut to a predetermined size. Although FIG. 3 shows only a part of the precursor element 9, it is preferable that the precursor element 9 is horizontally long to have a certain degree of productivity so that a plurality of laminated bodies 4 can be cut.

  As a material used for the piezoelectric ceramic layer 2, it is preferable to use a material having a high piezoelectric constant. For example, piezoelectric ceramic powder mainly composed of lead nickel niobate or lead zirconate titanate is used. The Moreover, as a material used for the internal electrode layer 3, electrode paste which consists of Cu, Ag, Pd, or these alloys can be used conveniently.

  Next, the insulating part 6 is formed on the internal electrode layer 3 exposed on the side surface of the precursor element 9 by depositing an insulating material every other layer by a method such as electrophoresis, and baking it. Further, a pair of external electrodes 5 are formed on the stacked body 4 so as to cover the insulating portion 6 and to be electrically connected to the internal electrode layer 3 every other layer.

Insulating portion 6, an inorganic oxide, in particular can inorganic oxide preferably used whose main component is SiO _2, it may be an insulating resin. Moreover, as a material used for the external electrode 5, an electrode paste made of Ag, Au, Ni, or an alloy thereof is preferably used. The external electrode 5 is preferably formed by a method such as screen printing, sputtering, or vapor deposition.

  FIG. 4 is a view showing a state in which the first exterior resin layer is formed on the precursor element of the multilayer piezoelectric ceramic element of the present invention. FIG. 5 is a view showing a state in which the precursor element of the multilayer piezoelectric ceramic element of the present invention is cut. In the precursor element 9 in which the insulating portion 6 and the external electrode 5 are formed, an exterior resin paste is applied and cured on both sides of the external electrode 5 by dispenser or screen printing to form a first exterior resin layer 8a. Thereafter, the cutting positions 10a and 10b in FIG. 4 are cut into predetermined dimensions using a diamond blade or the like, and the laminate 4 in FIG. 5 is manufactured. The internal electrode layer 3 is exposed on the cut surface thus cut.

  FIG. 6 is a diagram showing a state in which the second exterior resin layer is formed on the multilayer body of the multilayer piezoelectric ceramic element of the present invention, and FIG. 6A is a perspective view of the multilayer piezoelectric ceramic element of the present invention. FIG. 6B is an enlarged top view of a corner portion of the multilayer piezoelectric ceramic element of the present invention. The exterior resin paste is applied and cured by a dispenser or screen printing on the cut surface where the internal electrode layer 3 of the laminated body 4 that has been cut and processed is formed by forming the first exterior resin layer 8a, and the second exterior resin layer 8b is formed. By adopting the above manufacturing method, as shown in FIG. 6B, the second exterior resin layer 8b is also formed by the thickness of the first exterior resin layer 8a formed on both sides of the external electrode 5. I can do it. For this reason, the thickness of the corner portion of the multilayer piezoelectric ceramic element can be secured stably, and the thickness of the corner portion can be prevented from becoming extremely thin or exposed.

  The material used for the first exterior resin layer 8a and the second exterior resin layer 8b is preferably a resin with good moisture resistance, and examples thereof include fluorine resin, epoxy resin, and silicon resin. It is not limited to. Further, the first exterior resin layer 8a and the second exterior resin layer 8b may be made of different materials, or a plurality of these resins may be combined to form a multilayer structure.

  The multilayer piezoelectric ceramic element of the present invention will be specifically described with reference to examples.

Example 1
First, a piezoelectric ceramic powder mainly composed of lead zirconate titanate and lead nickel niobate was used and dispersed and mixed in an organic solvent together with a binder to prepare a slurry. This slurry was formed into a film by a doctor blade method to produce a green sheet having a thickness of 50 μm. An electrode paste made of Ag / Pd was screen-printed on a green sheet to a thickness of 5 μm and dried. Next, the green sheet on which the electrode paste was printed was laminated, fired at 1100 ° C. after hot pressing. The fired precursor element 9 is immersed in a bath in which glass powder is dispersed, and insulation is performed every other layer at a location where the internal electrode layers 3 on the pair of side surfaces facing the precursor element 9 are exposed by electrophoresis. Part 6 was formed. Thereafter, an electrode paste made of Ag was applied to a thickness of 5 μm by screen printing so as to cover the insulating portion 6 on the opposite side surface of the precursor element 9, and baked at 500 ° C. to form the external electrode 5. The precursor element 9 having a height of 3 mm, a lateral length of 2 mm, and a longitudinal length of 1.2 mm shown in FIG. 3 was produced by the manufacturing method described above. At this time, the length in the lateral direction of the precursor element 9 can be set to a size that is easy to manufacture in mass production. After the external electrodes 5 are formed at regular intervals and a first exterior resin layer 8a described later is formed. A plurality of laminated bodies 4 can be manufactured by cutting at a predetermined position.

  The exterior resin paste was screen printed and cured on both sides of the external electrode 5 of the precursor element 9 to form the first exterior resin layer 8a as shown in FIG. The exterior resin paste was prepared using a fluorine resin, an epoxy resin, and a silicon resin, respectively. The curing condition of the exterior resin paste was 150 ° C. for 1 hour, and the thickness after curing, that is, the thickness of the first exterior resin layer 8a was adjusted to 20 μm.

  Next, as shown in FIG. 5, the precursor element 9 was cut with a diamond blade so as to have a lateral length of 1.2 mm, so that a laminate 4 was formed. Accordingly, the laminate 4 has a prismatic shape with a height of 3 mm and a length and width of 1.2 mm.

  Further, the exterior resin paste is screen-printed and cured on the cut surface where the internal electrode layer 3 is exposed to form a second exterior resin layer 8b as shown in FIG. Element 1 was produced. The exterior resin paste was prepared using a fluorine resin, an epoxy resin, and a silicon resin, respectively. The curing condition of the exterior resin paste was 150 ° C. for 1 hour, and the thickness after curing, that is, the thickness of the second exterior resin layer 8b was adjusted to 20 μm. In this example, the same exterior resin paste was used for the first exterior resin layer 8a and the second exterior resin layer 8b.

(Comparative Example 1)
As a comparative example, a conventional multilayer piezoelectric ceramic element shown in FIG. 9 was produced. Since the material and manufacturing method which comprise the laminated body 4 were the same as that of the Example of this invention, description is abbreviate | omitted. The laminate 4 was in the shape of a prism having a height of 3 mm and a length and width of 1.2 mm. The exterior resin paste was screen printed and cured only on the pair of side surfaces where the internal electrode layer 3 of the laminate 4 was exposed, and the exterior resin layer 8c was formed to a thickness of 20 μm. The exterior resin paste was an epoxy resin, and the curing conditions were 150 ° C. and 1 hour.

  A high humidity load test was performed on the multilayer piezoelectric ceramic element of Example 1 manufactured by the above-described method and the conventional multilayer piezoelectric ceramic element manufactured as Comparative Example 1. In the high-humidity load test, DC 50V was applied to the laminated piezoelectric ceramic element in a constant temperature layer of an air atmosphere of 40 ° C. and 90% RH and driven for 1000 hours. When a predetermined time passed, the insulation resistance of each laminated piezoelectric ceramic element was measured.

  FIG. 7 shows the results of a high humidity load test of the multilayer piezoelectric ceramic element according to Example 1. As shown in FIG. 7, in comparison with the conventional multilayer piezoelectric ceramic element, the multilayer piezoelectric ceramic element of the present invention is less likely to decrease the insulation resistance even after 500 hours, and has improved humidity resistance. I understood it. Therefore, it is confirmed that by adopting the structure of the multilayer ceramic element of the present invention, it is possible to obtain a multilayer ceramic element excellent in long-term reliability in which the insulation resistance hardly deteriorates even in a high humidity environment. did it. In addition, the humidity resistance of the fluorine-based resin, epoxy-based resin, and silicon-based resin is improved compared to the conventional element, but it was also confirmed that the moisture resistance was best when the fluorine-based resin was used.

(Example 2)
The laminated piezoelectric ceramic element according to Example 2 will be specifically described. Since Example 2 is the same as the laminated piezoelectric ceramic element of Example 1 in material and manufacturing method, description thereof is omitted. In Example 2, the thicknesses of the first exterior resin layer 8a and the second exterior resin layer 8b are changed from 1 μm to 1000 μm, and the laminated piezoelectric ceramic elements 1 having different thicknesses of the respective exterior resin layers are respectively produced. did. As the exterior resin paste, fluorine resin, epoxy resin, and silicon resin were used.

(Comparative Example 2)
Since Comparative Example 2 is the same material and manufacturing method as the multilayer piezoelectric ceramic element of Comparative Example 1, description thereof is omitted. In Comparative Example 2, the thickness of the exterior resin layer 8c was changed from 1 μm to 1000 μm, and the laminated piezoelectric ceramic elements 1 having different thicknesses of the exterior resin layer 8c were produced. An epoxy resin was used as the exterior resin paste.

  FIG. 8 shows the results of a high-humidity load test conducted for 500 hours with the multilayer piezoelectric ceramic element according to Example 2. As shown in FIG. 8, it was found that when the thickness of the exterior resin layers 8 (8a, 8b) and 8c is 10 μm or more and 200 μm or less, the insulation resistance shows a high value. Further, it was found that the moisture resistance of the multilayer piezoelectric ceramic element of the present invention was improved as compared with the conventional multilayer piezoelectric ceramic element. If it is less than 10 μm or more than 200 μm, the insulation resistance value is low and the humidity resistance is poor. This is because the bubbles in the exterior resin layers 8 (8a, 8b) and 8c are confirmed to have a size of 3 μm to 10 μm, so that the outer resin layers 8 (8a, 8b) and 8c are less than 10 μm. This is because moisture permeates into defects such as contained bubbles and the insulation resistance decreases. Furthermore, when the thickness of each of the exterior resin layers 8 (8a, 8b) and 8c exceeds 200 μm, the exterior resin itself absorbs moisture, thereby promoting migration and lowering the insulation resistance.

  That is, by setting the thickness of the exterior resin layers 8 (8a, 8b) and 8c to 10 μm or more, even if there are defects such as bubbles, the exterior resin layer has a sufficient thickness, so that it can be insulated even in a high humidity environment. Resistance is unlikely to deteriorate. Further, by setting the thickness of the exterior resin layers 8 (8a, 8b) and 8c to 200 μm or less, the amount of moisture absorbed by the exterior resin is very small, and migration is unlikely to occur. Accordingly, the thickness of the exterior resin layers 8 (8a, 8b) and 8c is preferably 10 μm or more and 200 μm or less.

  As described above, by adopting the structure and manufacturing method of the multilayer piezoelectric ceramic element of the present invention, even in the multilayer piezoelectric ceramic element having a structure in which the external electrode is exposed on the surface, It became possible to ensure the thickness of the exterior resin layer at the corners of the piezoelectric ceramic element. Therefore, even when used in a high humidity environment, it has become possible to provide a laminated piezoelectric ceramic element having excellent reliability, in which insulation resistance is unlikely to deteriorate.

The figure which shows the laminated piezoelectric ceramic element of this invention. FIG. 1A is a top view of the multilayer piezoelectric ceramic element of the present invention. FIG. 1B is a perspective view of the multilayer piezoelectric ceramic element of the present invention. The figure which shows the state before the exterior of the lamination type piezoelectric ceramic element of this invention. The figure which shows a part of precursor element of the lamination type piezoelectric ceramic element of this invention. The figure which shows the state which formed the 1st exterior resin layer in the precursor element of the lamination type piezoelectric ceramic element of this invention. The figure which shows the state which cut | disconnected the precursor element of the lamination type piezoelectric ceramic element of this invention. The figure which shows the state which formed the 2nd exterior resin layer in the laminated body of the lamination type piezoelectric ceramic element of this invention. FIG. 6A is a perspective view of the multilayer piezoelectric ceramic element of the present invention. FIG. 6B is an enlarged top view of a corner portion of the multilayer piezoelectric ceramic element of the present invention. The result of the high humidity load test of the multilayer piezoelectric ceramic element according to Example 1. The result of having performed the high-humidity load test for 500 hours with the lamination type piezoelectric ceramic element which concerns on Example 2. FIG. The figure which shows the conventional lamination type piezoelectric ceramic element. FIG. 9A is a top view of a conventional multilayer piezoelectric ceramic element. FIG. 9B is a perspective view of a conventional multilayer piezoelectric ceramic element. The upper surface enlarged view of the corner | angular part of the conventional laminated piezoelectric ceramic element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laminated piezoelectric ceramic element 2 Piezoelectric ceramic layer 3 Internal electrode layer 4 Laminated body 5 External electrode 6 Insulating part 7a Displacement direction 7b Displacement direction 8a First exterior resin layer 8b Second exterior resin layer 8, 8c Exterior resin layer 9 Precursor element 10a Cutting position 10b Cutting position

Claims (7)

  A laminated body in which a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers are alternately laminated and integrated is provided, the internal electrode layer serves as a counter electrode, and the internal electrode layers exposed on the side surfaces of the laminated body are provided every other layer. A pair of external electrodes are formed that are covered with an insulating portion, cover the insulating portion, and are electrically connected to the internal electrode layer. The external electrode has an external terminal connection portion that is electrically connected to an external device. The external electrode serving as the external terminal connection portion is a laminated piezoelectric ceramic element exposed on the surface, and an exterior resin layer is formed on the side and corner portions of the laminate excluding the exposed external electrode forming portion. A laminated piezoelectric ceramic element characterized by being made.   2. The multilayer piezoelectric ceramic element according to claim 1, wherein the exterior resin layer includes any one selected from a fluorine resin, an epoxy resin, and a silicon resin.   3. The multilayer piezoelectric ceramic element according to claim 1, wherein a thickness of the exterior resin layer is 10 μm or more and 200 μm or less.   A laminated body in which a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers are alternately laminated and integrated is provided, the internal electrode layer is used as a counter electrode, and the internal electrode layers exposed on the side surfaces of the laminated body are provided every other layer. Covering with an insulating portion, covering the insulating portion to form a pair of external electrodes that are electrically connected to the internal electrode layer, the external electrodes having external terminal connection portions that are electrically connected to an external device A method of manufacturing a laminated piezoelectric ceramic element in which an external electrode serving as the external terminal connection portion is exposed on the surface, and an exterior resin layer is provided on the side surface and corner portion of the laminated body excluding the external electrode forming portion to be exposed. A method for producing a laminated piezoelectric ceramic element, comprising: forming a laminated piezoelectric ceramic element.   A plurality of piezoelectric ceramic layers and a plurality of internal electrode layers alternately stacked and integrated with a precursor formed by cutting a predetermined element into predetermined dimensions, the internal electrode layer serving as a counter electrode, and the precursor The internal electrode layer exposed on the side surface of the body element is covered with an insulating portion every other layer, and the pair of external electrodes that cover the insulating portion and are electrically connected to the internal electrode layer are formed, and the precursor element is cut And forming the laminate, wherein the external electrode has an external terminal connection portion electrically connected to an external device, and the external electrode serving as the external terminal connection portion is exposed on the surface. A method for manufacturing a multilayer piezoelectric ceramic element, comprising: forming an exterior resin layer on a side surface and a corner of the multilayer body excluding a portion where the external electrode to be exposed is exposed.   6. The method for manufacturing a multilayer piezoelectric ceramic element according to claim 5, wherein a first exterior resin layer is formed on both sides of an external electrode formed on a side surface of the precursor element of the multilayer piezoelectric ceramic element, and then the precursor. A method for producing a laminated piezoelectric ceramic element, comprising: cutting an element to form the laminate, and forming a second exterior resin layer on a cut surface of the precursor element.   The thickness of the said exterior resin layer shall be 10 micrometers or more and 200 micrometers or less, The manufacturing method of the laminated piezoelectric ceramic element in any one of the Claims 4-6 characterized by the above-mentioned.

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