JP3921171B2 - CERAMIC ELECTRONIC COMPONENT, ITS MANUFACTURING METHOD, AND INJECTION DEVICE - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic electronic component, a method for manufacturing the same, and an injection device, for example, a ceramic electronic component used for a precision positioning device such as a fuel injection device for an automobile and an optical device, a driving element for preventing vibrations, and the like It is about.
[0002]
[Prior art]
Conventionally, as a multilayer piezoelectric element, a multilayer piezoelectric actuator in which piezoelectric bodies and internal electrodes are alternately stacked is known. Multilayer piezoelectric actuators are classified into two types: the simultaneous firing type and the stack type in which piezoelectric ceramics and internal electrode plates are alternately laminated. Since the multilayer piezoelectric actuator of the type is advantageous for thinning, its superiority is being shown.
[0003]
FIG. 6 shows a conventional multilayer piezoelectric actuator. In this actuator, piezoelectric bodies 51 and internal electrodes 52 are alternately stacked. The internal electrodes 52 are formed on the entire main surface of the piezoelectric body 51. It has a so-called partial electrode structure. By laminating the internal electrodes 52 of this partial electrode structure alternately left and right, the internal electrodes 52 can be alternately connected to the external electrodes 70 formed on the side surfaces of the columnar laminated body 78. In FIG. 6, reference numeral 76 denotes a lead wire and 77 denotes solder.
[0004]
In such a multilayer piezoelectric actuator, conventionally, an internal electrode paste is printed on a ceramic green sheet in a pattern having a predetermined partial electrode structure, and a plurality of green sheets coated with the internal electrode paste are stacked to form a laminated molded body. It was produced and fired to produce a columnar laminate (see, for example, Patent Document 1).
[0005]
[Patent Document 1]
JP-A-11-68182
[0006]
[Problems to be solved by the invention]
However, in the multilayer piezoelectric actuator, the shrinkage behavior when the piezoelectric body is fired is different between the portion where the internal electrode paste is printed on the green sheet and the portion where the green electrode is not printed, so that delamination and cracks are likely to occur during firing. There was a problem.
[0007]
That is, the green sheet portion on which the internal electrode paste is printed is promoted by the catalytic action of a noble metal such as silver or palladium in the internal electrode paste, and the temperature is lower than the green sheet portion on which the internal electrode paste is not printed. From this, firing shrinkage started, and the shrinkage amount during firing increased, resulting in problems such as delamination and cracks occurring at the interface between the insulating layer and the conductor. In addition, even if delamination or cracks do not occur, there is a problem that residual stress is generated inside, causing damage when the actuator is driven.
[0008]
An object of this invention is to provide the ceramic electronic component which can suppress the failure | damage in the laminated interface of an insulating layer and a conductor, its manufacturing method, and an injection apparatus.
[0009]
[Means for Solving the Problems]
The ceramic electronic component of the present invention is a ceramic comprising an electronic component body in which a plurality of insulating layers are laminated, a conductor is interposed in a partial region between the insulating layers, and the insulating layer and the conductor are simultaneously fired. In an electronic component, in a conductor non-formation region between an end portion of the conductor embedded between the insulating layers and a side surface of the electronic component main body,50-95% by volumeWith insulation material5-50% by volumeA shrinkage adjustment layer containing a metal material and having an insulating property is formed.
[0010]
In such a ceramic electronic component, a part or all of the insulator in the conductor non-formation region,50-95% by volumeWith insulation material5-50% by volumeSince the shrinkage adjustment layer containing a metal material and having insulating properties is formed, the presence of the metal material in the shrinkage adjustment layer can improve the sinterability of the insulation layer in the vicinity of the conductor non-forming region. Thereby, the contraction rate of the insulator in the conductor formation region and the conductor non-formation region can be made substantially the same, and the occurrence of problems such as delamination can be prevented. In addition, since the shrinkage adjustment layer has an insulating property, the insulating property in the conductor non-forming region is not lowered.In particular, the shrinkage adjustment layer preferably contains 10 to 50% by volume of the metal material.
[0013]
In the ceramic electronic component of the present invention, the sheet resistance value of the shrinkage adjustment layer is 10⁶It is characterized by being Ω / □ or more. Thereby, the high insulation of a conductor non-formation area | region can be maintained, and insulation with the external electrode provided in the side surface of an electronic component main body can be ensured, for example. Moreover, it can form by making a conductor and a shrinkage | contraction adjustment layer contact.
[0016]
In the present invention, the thickness of the shrinkage adjustment layer is substantially the same as the conductor thickness. In such a ceramic electronic component, a step due to the conductor thickness can be prevented, deformation in the stacking direction of the ceramic electronic component can be suppressed, and delamination can be further suppressed.
[0017]
  The method for producing a ceramic electronic component of the present invention comprises a step of producing a laminated molded body in which a plurality of insulating layer molded bodies are laminated and a conductor pattern is interposed in a partial region between the insulating layer molded bodies, A method for producing a ceramic electronic component comprising a step of firing a multilayer molded body to produce an electronic component body, wherein the multilayer molded body is embedded between a side surface of the multilayer molded body and the insulating layer molded body. In the conductor pattern non-formation area between the conductor pattern ends,50-95% by volumeWith insulating material5-50% by volumeA shrinkage adjustment pattern containing a metal material is formed.
[0018]
According to such a manufacturing method, since the shrinkage adjustment layer pattern containing the insulating layer material and the metal material is formed on a part or all of the insulating layer molded body in the conductor pattern non-formation region, the conductor formation region and the conductor Since the shrinkage rate during firing of the insulator in the non-formed region can be approximated, problems such as delamination and cracks due to mismatch of the shrinkage rate of the insulator in the conductor forming region and the non-conductor formed region occur during firing Can be prevented. The metal material contained in the shrinkage adjusting layer may be a plurality of metal alloy particles such as silver-palladium and silver-platinum.
[0019]
The method for producing a ceramic electronic component of the present invention includes a step of producing a laminated molded body in which a plurality of insulating layer molded bodies are laminated and a conductor pattern is interposed in a partial region between the insulating layer molded bodies. A method for producing a ceramic electronic component comprising: firing the laminated molded body, and adjusting the shape of the side surface of the fired body to produce an electronic component main body, wherein the laminated molded body comprises the laminated molded body In a conductive pattern non-formation region between the side surface of the conductive layer and the conductive pattern end embedded between the insulating layer molded bodies, a metal material, or a shrinkage adjustment pattern containing an insulating material and a metal material is formed, and is configured. The shrinkage adjustment pattern is removed by the shape adjustment process after firing.
[0020]
Even in such a manufacturing method, the shrinkage rate during firing of the insulator in the conductor formation region and the conductor non-formation region can be approximated, so the shrinkage rate of the insulator in the conductor formation region and the conductor non-formation region during firing It is possible to prevent problems such as delamination and cracks due to the mismatch.
[0021]
In the ejection device according to the present invention, the ceramic electronic component is a multilayer piezoelectric element, the multilayer piezoelectric element is accommodated therein, a container having an ejection hole, and a liquid from the ejection hole by driving the multilayer piezoelectric element. And a valve for jetting.
[0022]
In such an injection device, as described above, the residual stress at the time of firing that occurs at the laminated interface in the multilayer piezoelectric element itself can be eliminated and the durability can be greatly improved, so that the durability of the injection device can also be improved.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
1A and 1B show one embodiment of a multilayer piezoelectric element that is an electronic component of the present invention. FIG. 1A is a perspective view, FIG. 1B is an exploded perspective view showing an enlarged multilayer structure, and FIG. (D) is a longitudinal sectional view taken along line BB ′ in (a). 2A is an enlarged view of a portion C in FIG. 1C, and FIG. 2B is an enlarged view of a portion D in FIG.
[0024]
As shown in FIG. 1, the multilayer piezoelectric element of the present invention is composed of a columnar electronic component body 1a and external electrodes 4 provided on opposite sides of the electronic component body 1a. Reference numeral 1a denotes a plurality of stacked piezoelectric bodies 1 (insulators) and internal electrodes 2 (conductors) of so-called partial electrode patterns formed between the piezoelectric bodies 1 so that the internal electrodes 2 are alternately left and right. It has a laminated structure.
[0025]
That is, the internal electrode 2 has a rectangular shape, one end of which is exposed on the side surface of the electronic component main body 1a, and the other three ends are embedded in the electronic component main body 1a. On opposite side surfaces of the electronic component main body 1a, the end portions of the internal electrodes 2 are alternately exposed, and positive and negative external electrodes 4 are formed at the end portions. More specifically, the end portions of the internal electrodes 2 are exposed on the surface of the electronic component main body 1a where the external electrodes 4 are formed, and each internal electrode 2 is exposed to the positive or negative external electrode 4 every other layer. Electrically joined. On the other hand, one end of the internal electrode 2 not connected to the external electrode 4 is not exposed on the side surface of the electronic component main body 1a. Furthermore, a lead wire 6 is connected and fixed to the external electrode 4 with solder or the like.
[0026]
The piezoelectric body 1 is made of, for example, lead zirconate titanate Pb (Zr, Ti) O._Three(Hereinafter abbreviated as PZT) or barium titanate BaTiO_ThreeIt is formed with the piezoelectric ceramic material etc. which have as a main component. This piezoelectric ceramic has a piezoelectric strain constant d indicating its piezoelectric characteristics.₃₃A high value is desirable.
[0027]
The thickness of the piezoelectric body 1, that is, the distance between the internal electrodes 2 is preferably 50 to 250 μm. In order to obtain a larger amount of displacement by applying a voltage to the multilayer piezoelectric element, a method of increasing the number of layers is taken, but when the number of layers is increased, the piezoelectric body 1 is too thick. This is because the multilayer piezoelectric element cannot be reduced in size and height, and if the thickness of the piezoelectric body 1 is too thin, dielectric breakdown tends to occur.
[0028]
The electronic component main body 1a includes an active portion 8 in which the piezoelectric bodies 1 and the internal electrodes 2 are alternately stacked and an inactive portion 9 formed on the upper and lower ends of the active portion 8 in order to generate a displacement amount. An internal electrode 2 having a thickness of 0.5 to 10 μm is disposed between the piezoelectric bodies 1 in the active portion 8, and the internal electrode 2 is made of a metal material such as silver-palladium, A predetermined voltage is applied to each piezoelectric body 1 in the active portion 8 to cause the piezoelectric body 1 to be displaced by the reverse piezoelectric effect.
[0029]
Further, the lead wire 6 is connected and fixed to the external electrode 4 by soldering. The lead wire 6 serves to connect the external electrode 4 to an external voltage supply unit.
[0030]
In the present invention, as shown in FIG. 2, the density of the piezoelectric body 1b in the conductor forming region X in which the internal electrode 2 is formed and the density of the piezoelectric body 1c in the conductor non-forming region Y in which the internal electrode 2 is not formed are It is substantially the same throughout the entire area.
[0031]
That is, the density of the piezoelectric body 1 in the conductor non-formation region Y between the end 2a of the internal electrode 2 embedded between the piezoelectric bodies 1 and the side surface of the electronic component main body 1a is other (conductor formation region X). The density of the body 1 is substantially the same.
[0032]
Here, the piezoelectric body 1b in the conductor forming region X (sometimes referred to as the vicinity of the internal electrode 2 forming portion) is within a half of the thickness of the piezoelectric body 1 from the internal electrode 2, that is, a distance between the internal electrodes 2. It refers to the region of the piezoelectric body 1 at a portion within a distance of 1/2. Conversely, the piezoelectric body 1c in the conductor non-formation region Y (sometimes referred to as the vicinity of the internal electrode 2 non-formation portion) is half the thickness of the piezoelectric body 1 from the internal electrode 2, that is, the distance between the internal electrodes 2. The area of the piezoelectric body 1 at a part farther than ½ of.
[0033]
Further, the density is substantially the same, the difference in density between the piezoelectric body 1b in the vicinity of the internal electrode 2 forming portion and the piezoelectric body 1c in the vicinity of the internal electrode 2 non-forming portion is within 5%, in other words, the piezoelectric body 1b and the piezoelectric body. The quotient obtained by dividing the density difference of 1c by the density of the piezoelectric body 1b is within 5%. The density difference is preferably within 1%. The density difference between the piezoelectric body 1b in the vicinity of the internal electrode 2 forming portion and the piezoelectric body 1c in the vicinity of the internal electrode 2 non-forming portion is preferably within 2% from the viewpoint of reducing the residual stress during firing.
[0034]
That is, since the density of the piezoelectric body 1b in the vicinity of the internal electrode 2 formation portion and the density of the piezoelectric body 1c in the vicinity of the internal electrode 2 non-formation portion are substantially equal, the piezoelectric body 1b and the internal electrode 2 in the vicinity of the internal electrode 2 formation portion during firing. The contraction rate of the piezoelectric body 1c in the vicinity of the non-formed part becomes substantially equal, and delamination, cracks, and the like can be prevented from occurring at the lamination interface during firing.
[0035]
In addition, since the contraction rate of the piezoelectric body 1b in the vicinity of the internal electrode 2 forming portion and the piezoelectric body 1c in the vicinity of the internal electrode 2 non-forming portion are substantially equal, it is possible to prevent the occurrence of residual stress, and the multilayer piezoelectric element Even in the case of driving, it is possible to obtain high reliability without being damaged at and near the laminated interface.
[0036]
As described above, in order to make the density of the piezoelectric body 1b in the vicinity of the internal electrode 2 formation portion and the density of the piezoelectric body 1c in the vicinity of the internal electrode 2 non-formation portion substantially equal, for example, the piezoelectric body 1 in the internal electrode 2 non-formation portion. A shrinkage adjustment layer 13 containing a piezoelectric material and a metal material is formed on all of them. As a result, the metal material in the shrinkage adjustment layer 13 improves the sinterability of the piezoelectric body 1c in the vicinity of the portion where the internal electrode 2 is not formed during firing, so that the shrinkage rates of the piezoelectric body 1b and the piezoelectric body 1c are substantially equal. It is possible to prevent delamination and the like from occurring during firing.
[0037]
The metal material in the shrinkage adjusting layer 13 is made of metal particles such as silver or a plurality of alloys such as silver-palladium and silver-platinum.
[0038]
The sheet resistance value of the shrinkage adjustment layer 13 is 10⁶Ω / □ or more. Thereby, the end 2a of the internal electrode 2 that is not connected to the external electrode 4 and the external electrode 4 maintain high insulation. The sheet resistance value is obtained by multiplying the resistance value of the measured object by the width of the measured object and dividing the result by the length. In other words, the volume resistivity of the measured object is divided by the thickness of the measured object. Such a shrinkage adjustment layer 13 can also be in contact with the internal electrode 2 as shown in FIG. The sheet resistance value of the shrinkage adjustment layer 13 is 10⁶When it is smaller than Ω / □, it is necessary to form the shrinkage adjustment layer 13 separately from the internal electrode 2.
[0039]
Furthermore, in the present invention, high insulation between the end 2a of the internal electrode 2 that is not connected to the external electrode 4 and the external electrode 4 is maintained, and the piezoelectric body 1b in the vicinity of the internal electrode 2 formation portion and the vicinity of the non-internal electrode 2 formation portion. In order to make the firing shrinkage rate of the piezoelectric body 1c substantially equal, it is desirable that the shrinkage adjustment layer 13 be formed of 5 to 50% by volume of the metal material and the balance of the piezoelectric material 50 to 95%. As a result, the sheet resistance value of the shrinkage adjustment layer 13 is 10.⁶It can also be set to Ω / □ or more.
[0040]
In the present invention, it is desirable that the metal material constituting the shrinkage adjustment layer 13 is the same as the metal material constituting the internal electrode 2. Since the metal material of the shrinkage adjustment layer 13 is the same as the metal material constituting the internal electrode 2, the shrinkage behavior when the piezoelectric body 1c is fired can be matched with the shrinkage behavior of the piezoelectric body 1b. It is possible to further prevent the occurrence of delamination and cracks in the vicinity thereof.
[0041]
The thickness of the shrinkage adjustment layer 13 is preferably the same as the thickness of the internal electrode 2. Thereby, a step due to the thickness of the internal electrode 2 can be prevented, deformation in the stacking direction of the ceramic electronic component can be suppressed, and delamination can be further suppressed.
[0042]
In the above example, the example in which the shrinkage adjustment layer 13 containing the piezoelectric material and the metal material is formed on the entire surface of the piezoelectric body 1 where the internal electrode 2 is not formed has been described. For example, FIG. Although it may be formed only on one of the parts shown in (b), it is desirable to form it on the part shown in FIG.
[0043]
In the above example, the example in which the inner conductor 2 and the shrinkage adjustment layer 13 are continuously formed has been described. However, the shrinkage adjustment layer 13 may be formed apart from the inner conductor 2. In this case, the insulation between the inner conductor 2 and the shrinkage adjustment layer 13 can be further ensured. On the other hand, since it is spaced apart, the metal content of the shrinkage adjustment layer 13 can be increased, and the shrinkage behavior can be further approximated.
[0044]
A method for producing the multilayer piezoelectric element of the present invention will be described.
[0045]
First, a calcined powder of piezoelectric ceramics such as PZT, a binder made of an organic polymer such as acrylic or butyral, and a plasticizer such as DBP (diethyl phthalate) or DOP (dibutyl phthalate) are mixed. A slurry is prepared, and a ceramic green sheet to be the piezoelectric body 1 is prepared from the slurry by a tape molding method such as a well-known doctor blade method or calendar roll method.
[0046]
Next, a metal powder composed of silver-palladium is mixed with ceramic powder such as PZT, binder, plasticizer, etc. as a co-material to produce an internal electrode paste, which is screen printed on the upper surface of each ceramic green sheet, etc. To a thickness of 1 to 40 μm to form an internal electrode pattern on the green sheet.
[0047]
Separately, a binder, a plasticizer, and the like are added to and mixed with a mixture of 5 to 50% by volume of metal powder made of silver-palladium and 50 to 95% by volume of the same ceramic calcined powder as the piezoelectric body 1. A shrinkage adjusting paste is prepared, and this is printed on a part or all of the internal electrode pattern non-printing area on the ceramic green sheet printed with the internal electrode pattern to a thickness of 1 to 40 μm by screen printing or the like. An adjustment pattern is formed.
[0048]
When the metal material contained in the shrinkage adjustment paste is 5 to 50% by volume, the piezoelectric body 1c in the vicinity of the internal electrode 2 non-formed portion is fired without reducing the insulating property of the internal electrode 2 non-formed portion. Can be matched to the contraction rate of the piezoelectric body 1b in the vicinity of the internal electrode 2 forming portion.
[0049]
Furthermore, it is preferable that the shrinkage behavior of the piezoelectric body 1b and the piezoelectric body 1c at the time of firing is matched to eliminate residual stress at the time of firing and to prevent deterioration of insulation at high temperatures. The metal material contained in is preferably in the range of 10 to 30% by volume.
[0050]
In addition, the metal material contained in the paste for shrinkage adjustment may be alloy particles composed of a plurality of metal components. Further, in order to effectively match the shrinkage behavior during firing of the piezoelectric body 1b and the piezoelectric body 1c, the metal material contained in the shrinkage adjustment paste is the same as the metal material contained in the internal electrode paste. Is desirable.
[0051]
Then, a plurality of ceramic green sheets each having an internal electrode pattern and a shrinkage adjustment layer pattern formed on the upper surface were laminated to produce a columnar laminated molded body, and the binder was removed from the columnar laminated molded body at a predetermined temperature. Thereafter, firing is performed at 900 to 1200 ° C., and the shape of the fired body is adjusted to a predetermined shape to obtain an electronic component main body.
[0052]
Thereafter, an external electrode paste made of silver powder and glass powder is applied to the opposing side surfaces of the electronic component body where the internal electrodes 2 are alternately exposed, and the external electrodes 4 are baked at 550 to 900 ° C. Form. Thereafter, the lead wire 6 is connected to the external electrode 4, a direct current voltage of 0.1 to 3 kV / mm is applied to the pair of external electrodes 4 via the lead wire 6, and the electronic component body 1 a is polarized, A laminated piezoelectric element as a product is completed.
[0053]
Next, another method for producing the multilayer piezoelectric element of the present invention will be described. As before, first, a ceramic green sheet is produced.
[0054]
Next, the internal electrode paste is printed on the ceramic green sheet to a thickness of 1 to 40 μm by screen printing or the like, and the internal electrode pattern is printed on the green sheet.
[0055]
Separately, a binder, a plasticizer, and the like are added to and mixed with a mixture of 5 to 50% by volume of metal powder made of silver-palladium and 50 to 95% by volume of the same ceramic calcined powder as the piezoelectric body 1. The paste for shrinkage adjustment is prepared, and this is printed to a thickness of 1 to 40 μm by screen printing or the like on part or all of the upper surface of the ceramic green sheet, which is to be removed in the shape processing step after firing. A pattern is formed. Note that the shrinkage adjustment paste printed on a part or all of the ceramic green sheet corresponding to the portion removed in the shape adjustment processing is removed in the shape adjustment processing and does not remain in the product. Then, it may be formed using an internal electrode paste.
[0056]
Next, a plurality of ceramic green sheets having internal electrode patterns and shrinkage adjustment patterns formed on the upper surface are laminated to produce a laminated molded body, and after debinding at a predetermined temperature for the laminated molded body, Bake at 900-1200 ° C.
[0057]
Then, shape adjustment processing of the fired body is performed by grinding and polishing the side surface of the fired body. At this time, the shrinkage adjustment layer is removed by the shape adjustment processing step.
[0058]
Note that the shrinkage adjustment paste may be applied not only to the portion removed by the shape adjustment processing but also to a position corresponding to the internal electrode non-formation region Y. In this case, the density can be further reduced.
[0059]
Thereafter, an external electrode paste made of silver powder and glass powder is applied to the side surfaces where the internal electrodes 2 are alternately exposed, and the external electrodes 4 are formed by baking at 550 to 900 ° C. Thereafter, the lead wire 6 is connected to the external electrode 4, a direct current voltage of 0.1 to 3 kV / mm is applied to the pair of external electrodes 4 via the lead wire 6, and the electronic component body 1 a is polarized, A laminated piezoelectric element as a product is completed.
[0060]
If the lead wire 6 of the multilayer piezoelectric element manufactured as described above is connected to an external voltage supply unit and a voltage is applied to the internal electrode 2 via the lead wire 6 and the external electrode 4, each piezoelectric body 1. Is largely displaced by the inverse piezoelectric effect, and functions as a fuel injection valve for an automobile for supplying fuel to the engine, for example.
[0061]
In the multilayer piezoelectric element configured as described above, the density of the piezoelectric body 1b in the vicinity of the internal electrode 2 forming portion and the density of the piezoelectric body 1c in the vicinity of the internal electrode 2 non-forming portion are substantially equal. And the piezoelectric body 1c have substantially the same shrinkage rate, and it is possible to prevent the occurrence of problems such as delamination occurring at the lamination interface at the time of firing and cracks occurring near the lamination interface.
[0062]
In particular, in a laminated piezoelectric element, even when delamination or cracks do not occur at the lamination interface during firing, if residual stress is present at the lamination interface during firing, the piezoelectric element itself is distorted (stretched) during use. Although there is a possibility of breakage in the vicinity thereof, if the multilayer piezoelectric element of the present invention is used, stress does not remain at the lamination interface at the time of firing, so that the problem of damage at or near the lamination interface during driving is prevented. be able to.
[0063]
Further, even when the laminated piezoelectric element is driven, the durability can be greatly improved without being damaged at and near the laminated interface.
[0064]
FIG. 3 shows an injection device according to the present invention. In the figure, reference numeral 31 denotes a storage container. An injection hole 33 is provided at one end of the storage container 31, and a needle valve 35 that can open and close the injection hole 33 is stored in the storage container 31.
[0065]
A fuel passage 37 is provided in the injection hole 33 so as to be able to communicate. The fuel passage 37 is connected to an external fuel supply source, and fuel is always supplied to the fuel passage 37 at a constant high pressure. Therefore, when the needle valve 35 opens the injection hole 33, the fuel supplied to the fuel passage 37 is formed to be injected into a fuel chamber (not shown) of the internal combustion engine at a constant high pressure.
[0066]
Further, the upper end portion of the needle valve 35 has a large diameter, and serves as a piston 41 slidable with a cylinder 39 formed in the storage container 31. In the storage container 31, the laminated piezoelectric element 43 described above is stored.
[0067]
In such an injection device, when the laminated piezoelectric element 43 is extended by applying a voltage, the piston 41 is pressed, the needle valve 35 closes the injection hole 33, and the fuel supply is stopped. When the voltage application is stopped, the laminated piezoelectric element 43 contracts, the disc spring 45 pushes back the piston 41, and the injection hole 33 communicates with the fuel passage 37 so that fuel is injected. .
[0068]
【Example】
Example 1
First, on the upper surface of the ceramic green sheet containing the PZT powder, an internal electrode pattern made of silver-palladium alloy, PZT powder, and a binder is formed by screen printing as shown in FIG. A shrinkage adjustment paste was printed on the entire surface of the ceramic green sheet where the internal electrode pattern was not formed to form a shrinkage adjustment pattern. Next, 300 ceramic green sheets on which the internal electrode pattern and the shrinkage adjustment layer pattern were formed were laminated to prepare a columnar laminated molded body.
[0069]
In addition, the paste for shrinkage | contraction adjustment adds a binder to solid content which consists of 20 volume% of silver-palladium alloy powder which forms an internal electrode, and 80 volume% of the same PZT powder contained in the said ceramic green sheet. It was produced.
[0070]
Thereafter, the laminated molded body was subjected to binder removal treatment at 400 ° C. and fired at 1050 ° C. in the air to obtain a fired body. Further, the side surface of the fired body was processed with a surface grinder to produce an electronic component body. Thereafter, an external electrode paste made of silver powder and glass powder is applied to the external electrode forming surface of the electronic component body, and baking is performed at 800 ° C. to form the external electrode 4. Thereafter, the lead wire 6 was connected to the external electrode 4.
[0071]
Thereafter, a 3 kV / mm direct current electric field was applied to the positive and negative external electrodes via lead wires for 15 minutes to carry out a polarization treatment, thereby producing a multilayer piezoelectric element as shown in FIG.
[0072]
The thickness of the piezoelectric body in the active part was 150 μm, the thickness of the internal electrode was 3 μm, and the thickness of the shrinkage adjusting layer was 3 μm.
[0073]
In the obtained multilayer piezoelectric element, the density of the piezoelectric body in the vicinity of the internal electrode forming portion is 7.90 g / cm.^ThreeThe density of the piezoelectric body in the vicinity of the internal electrode non-formation portion is 7.85 g / cm.^ThreeThe density difference was 0.6%, which was substantially the same. Further, when the sheet resistance of the shrinkage adjusting layer was measured with an insulation resistance meter, 8 × 10⁸It was Ω / □. Also, no abnormalities such as delamination and cracks were observed at the laminated interface.
Example 2
Next, an electronic component body similar to that of Example 1 was produced except that the volume ratio of the silver-palladium alloy and the piezoelectric body (PZT calcined body) constituting the shrinkage adjustment layer was changed. For the obtained electronic component main body, the bulk density of the piezoelectric body in the vicinity of the internal electrode forming portion and the piezoelectric body in the vicinity of the internal electrode non-forming portion was measured by the Archimedes method. The difference in bulk density of the piezoelectric body in the vicinity of the forming portion was calculated. In addition, the delamination and crack generation at the laminated interface and its vicinity were investigated. Furthermore, the sheet resistance of the shrinkage adjustment layer was measured.
[0074]
FIG. 4 shows the relationship between the bulk density difference between the piezoelectric body in the vicinity of the internal electrode forming portion and the piezoelectric body in the vicinity of the internal electrode non-forming portion, and the defect rate of delamination and cracks at the laminated interface. The difference in bulk density between the piezoelectric body near the internal electrode forming part and the piezoelectric body near the internal electrode non-forming part is the difference in bulk density between the piezoelectric body near the internal electrode forming part and the piezoelectric body near the internal electrode non-forming part. The quotient divided by the bulk density of the piezoelectric body in the vicinity of the electrode forming portion is expressed as a percentage. It can be seen from FIG. 4 that as the bulk density difference between the piezoelectric body near the internal electrode forming portion and the piezoelectric body near the internal electrode non-forming portion increases, defects due to delamination and cracks increase.
[0075]
The sample of the comparative example in which the shrinkage adjusting layer was not formed had a bulk density difference of 11.5%, and the defect rate was 15%.
[0076]
FIG. 5 shows the relationship between the volume percentage of the silver-palladium alloy in the shrinkage adjustment layer, the bulk density difference, and the sheet resistance of the shrinkage adjustment layer. It can be seen that when the metal component in the shrinkage adjusting layer is smaller than 5% by volume, the bulk density difference becomes larger than 5%, and defects such as delamination and cracks frequently occur. In addition, when the metal component in the shrinkage adjustment layer is larger than 50% by volume, the sheet resistance value of the shrinkage adjustment layer becomes small, and the insulating property of the internal electrode non-forming portion is lowered.
[0077]
That is, when the amount of the metal component in the shrinkage adjustment layer is 5 to 50% by volume within the range specified in the present invention, the piezoelectric body substantially in the vicinity of the internal electrode forming portion and the piezoelectric body in the vicinity of the internal electrode non-forming portion It can be seen that the densities are equal, it is possible to prevent the occurrence of defects such as delamination and cracks at or near the laminated interface, and there is no deterioration in the insulating properties of the internal electrode non-formed portion.
[0078]
【The invention's effect】
According to the ceramic electronic component of the present invention, in the conductor non-formation region between the conductor end buried between the insulating layers and the side surface of the electronic component main body,50-95% by volumeWith insulation material5-50% by volumeSince the shrinkage adjusting layer containing a metal material and having an insulating property is formed, the presence of the shrinkage adjusting layer containing the metal material improves the sinterability of the insulator in the conductor non-forming region. Thereby, the contraction rate of the insulator in the conductor formation region and the conductor non-formation region can be made substantially the same, and the occurrence of problems such as delamination can be prevented. In addition, since the shrinkage adjusting layer has an insulating property, the insulating property of the conductor non-forming region is not lowered. As a result, delamination and cracks are not generated at or near the laminated interface during firing, and high reliability is ensured that the laminated piezoelectric element is not damaged even when the laminated piezoelectric element is driven. The provided ceramic electronic component can be provided.
[Brief description of the drawings]
1A and 1B show a laminated piezoelectric element of the present invention, in which FIG. 1A is a perspective view, FIG. 1B is an exploded perspective view showing an enlarged laminated structure, and FIG. 1C is an AA ′ view of FIG. (D) is a longitudinal sectional view taken along line BB ′ in (a).
2A is an enlarged view of a portion C in FIG. 1C, and FIG. 2B is an enlarged view of a portion D in FIG.
FIG. 3 is an explanatory view showing an injection device of the present invention.
FIG. 4 is a graph showing a relationship between a defect density and a bulk density difference between a piezoelectric body near an internal electrode forming portion and a piezoelectric body near an internal electrode non-forming portion.
FIG. 5 is a graph showing the relationship between the ratio of the metal component in the shrinkage adjustment layer, the difference in bulk density between the piezoelectric body near the internal electrode forming portion and the piezoelectric body near the internal electrode non-forming portion, and the sheet resistance of the shrinkage adjustment layer. is there.
6A and 6B show a conventional multilayer piezoelectric element, in which FIG. 6A is a perspective view, and FIG. 6B is an exploded perspective view showing an enlarged multilayer structure.
[Explanation of symbols]
1 ... Piezoelectric body (insulator)
1a: electronic component body
2 ... Internal electrode
13 ... Shrinkage adjustment layer
31 ... Storage container
33 ... Injection hole
35 ... Valve
43 ... Multilayer piezoelectric element

Claims (9)

A ceramic electronic component comprising an electronic component body in which a plurality of insulating layers are laminated, a conductor is interposed in a partial region between the insulating layers, and the insulating layer and the conductor are simultaneously fired,
The conductor non-formation region between the end portion of the conductor buried between the insulating layers and the side surface of the electronic component main body contains 50 to 95 vol% insulating material and 5 to 50 vol% metal material. A ceramic electronic component comprising a shrinkage adjusting layer having an insulating property. The ceramic electronic component according to claim 1 , wherein the shrinkage adjustment layer contains 10 to 50% by volume of the metal material. The ceramic electronic component according to claim 1 or 2, characterized in that the sheet resistance value of the shrinkage adjustment layer is 10 ⁶ Ω / □ or more. The ceramic electronic component according to any one of claims 1 to 3 , wherein the thickness of the shrinkage adjustment layer is substantially the same as the thickness of the conductor. The ceramic electronic component according to any one of claims 1 to 4 , wherein the ceramic electronic component functions as a multilayer piezoelectric element. The ceramic electronic component according to any one of claims 1 to 5 , wherein the ceramic electronic component is a multilayer piezoelectric element, the multilayer piezoelectric element is accommodated therein, a container having an ejection hole, and the ejection hole by driving the multilayer piezoelectric element. And a valve for ejecting liquid from the jetting apparatus. A step of producing a laminated molded body in which a plurality of insulating layer molded bodies are laminated and a conductor pattern is interposed in a partial region between the insulating layer molded bodies, and firing the laminated molded body to form an electronic component main body A method of manufacturing a ceramic electronic component comprising: a step of forming a conductor pattern between a side surface of the laminate molded body and an end of the conductor pattern embedded between the insulating layer molded bodies. A method for producing a ceramic electronic component, wherein a shrinkage adjustment pattern containing 50 to 95% by volume of an insulating material and 5 to 50% by volume of a metal material is formed in the formation region.   A step of producing a laminated molded body in which a plurality of insulating layer molded bodies are laminated and a conductor pattern is interposed in a partial region between the insulating layer molded bodies, and firing the laminated molded body, the fired body And manufacturing the electronic component main body by adjusting the shape of the side surface of the ceramic electronic component, wherein the multilayer molded body is embedded between the side surface of the multilayer molded body and the insulating layer molded body. A shrinkage adjustment pattern containing an insulating material and a metal material is formed in the conductor pattern non-formation region between the conductor pattern ends, and the shrinkage adjustment pattern is removed by the shape adjustment process after firing. A manufacturing method for ceramic electronic components. Producing a ceramic green sheet containing piezoelectric ceramic powder;
Producing an internal electrode paste containing metal powder;
Producing a paste for shrinkage adjustment layer comprising a mixture containing 50 to 95% by volume of an insulating material and 5 to 50% by volume of a metal material;
Printing the internal electrode paste on a part of the upper surface of the ceramic green sheet to form an internal electrode pattern;
Forming the shrinkage adjustment pattern by printing the shrinkage adjustment paste on a part or all of the non-printing area where the internal electrode paste is not printed on the upper surface of the ceramic green sheet;
A ceramic ground having the internal electrode pattern and the shrinkage adjustment pattern formed on the upper surface. A step of laminating a plurality of lean sheets to produce a laminated molded body,
Firing the laminated molded body, and a method for producing a ceramic electronic component.

Images