JP4663495B2 - Anti-reaction material for lead-containing compounds - Google Patents

Description

  The present invention relates to an application to a firing jig mainly used for heat treatment such as firing of electronic material parts. For example, ceramic capacitors, ceramic filters, ceramic resonators, fuel injection injector actuators, and inkjet printer head actuators. Various heat treatments such as firing of piezoelectric elements such as piezoelectric resonators, oscillators, ultrasonic motors, acceleration sensors, knocking sensors, piezoelectric sensors such as AE sensors, baking of electrodes on piezoelectric elements, annealing of lead-containing compounds, etc. It can be applied to jigs that are preferably used in the above.

  Conventionally, products using a piezoelectric ceramic include, for example, an actuator, a filter, a piezoelectric resonator (including an oscillator), an ultrasonic vibrator, an ultrasonic motor, a piezoelectric sensor, and the like.

Among these, actuators have a very high response speed to electrical signals of the order of 10 ⁻⁶ seconds, so they are applied to XY stage positioning actuators for semiconductor manufacturing equipment, ink ejection actuators for inkjet printers, and the like. Yes.

  Piezoelectric ceramics used in such actuators use lead-containing compounds such as lead-containing ceramics such as lead zirconate titanate (hereinafter sometimes simply referred to as PZT). In such a lead-containing compound, since the volatility of lead is high, there is a problem that the composition evaporates from the molded body during firing and causes a composition variation of the sintered body, resulting in a non-uniform composition. In particular, the composition variation on the surface of the sintered body was large compared to the inside.

  Therefore, for firing a molded body containing a volatile component such as lead, the composition containing the volatile component contained in the molded body is the same as or similar to that of the molded body. It has been proposed to suppress the evaporation of the components, suppress the composition fluctuation of the molded body, particularly the composition fluctuation and the structure change near the surface, and make the characteristics of the sintered body uniform (for example, Patent Documents). 1).

  However, even if firing is performed by the method described in Patent Document 1 or Patent Document 2 and volatile components such as lead are prevented from evaporating from the sintered body to the atmosphere during firing, the sintered body contacts during firing. As a result, the surface of the sintered body in contact with the firing jig was changed in composition or changed in structure. In particular, when firing a multilayer body of ceramic green sheets having a thickness of several hundred μm or less, there is a problem that machining is difficult because the thickness is thin even if an altered phase on the surface of the sintered body is to be removed.

  In addition, because the shrinkage varies depending on the site due to compositional variation due to reaction with the firing jig during sintering, deformation such as undulation and warpage occurs, or unevenness is locally generated to obtain a smooth piezoelectric ceramic. There was a problem that was difficult.

  Furthermore, there is a problem that the piezoelectric characteristics vary depending on the site due to compositional variation due to reaction with the firing jig during sintering, and when used in a print head of an ink jet printer, ink discharge variation becomes large, and the image quality is high. There was a problem of lowering.

For this reason, for example, the use of cubic zirconia (ZrO ₂ ) stabilized by CaO or Y ₂ O _{3 having} low reactivity with piezoelectric ceramics as a firing jig is disclosed (for example, see Patent Document 3). ).

In addition, the firing jig is required to be used in a multi-stage stack in order to increase the processing capacity of firing, and thinning is being studied. In order to cope with the thinning, the sintered body needs to have high strength, and Al ₂ O ₃ is sometimes added to improve the sinterability of the zirconia sintered body and increase the strength.
Japanese Patent Laid-Open No. 10-29872 FIG. Japanese Patent Laid-Open No. 2004-338777 FIG. JP 2004-315293 A

However, even when cubic zirconia stabilized with CaO or Y ₂ O ₃ is used as a firing jig when firing a molded body containing a lead-containing compound such as PZT, the firing jig and the lead-containing compound such as PZT are used. There was a problem of slight reaction with lead on the surface of the molded body. In particular, the Al ₂ O ₃ crystals added to improve the sinterability and increase the strength of the firing jig are unevenly distributed at the grain boundaries of the zirconia crystals, so that the firing jig and lead partially react. There is a problem that the composition of the surface of the sintered body in contact with the firing jig becomes non-uniform, and the characteristics of the sintered PZT sintered body vary.

  For example, when PZT is fired as a piezoelectric ceramic, the piezoelectric characteristics of the obtained sintered body vary. Therefore, when a plurality of piezoelectric displacement elements are formed on one piezoelectric ceramic, the piezoelectric characteristics differ among the piezoelectric displacement elements. It was.

  Furthermore, when a molded body containing lead is repeatedly fired using the same firing jig, the reaction with lead on the firing jig surface gradually proceeds, and the lead content of the firing jig gradually increases and evaporates from the firing jig. Depending on the firing temperature and the firing temperature range, lead moved from the firing jig to the molded body, and the like, there is a problem that the piezoelectric characteristics of the sintered body vary greatly.

  Accordingly, an object of the present invention is to provide a reaction preventing member for a lead-containing compound having a very low reactivity with PZT and a high strength.

The reaction preventing member for lead-containing compounds of the present invention, cubic crystallized zirconia as the main crystalline phase consists distearate zirconia sintered body to contain 20～43Mol% stabilizing agent, the zirconia crystals of the zirconia sintered body The spinel is present at the grain boundary and substantially no Al ₂ O ₃ crystal is present.
It is preferable that the zirconia sintered body does not substantially contain Si.

  The reaction preventing member for the lead-containing compound of the present invention preferably contains 0.1 to 1% by mass of spinel and has a bending strength of 200 MPa or more.

It is preferable that the cubic ratio _Xc of the zirconia sintered body represented by the following formulas 1 and 2 is 0.97 or more.

  In the zirconia crystal, it is preferable that the stabilizer is dissolved in the solid solution limit.

  The total amount of the stabilizer added to the zirconia sintered body is preferably 20 to 43 mol%, and the average crystal particle diameter of the sintered body is preferably 10 to 40 μm.

According to the reaction preventing member for a lead-containing compound of the present invention, a zirconia sintered body containing cubic zirconia as a main crystal phase and containing 20 to 43 mol% of a stabilizer, the zirconia crystal grains of the zirconia sintered body Spinel exists in the boundary, and Al ₂ O ₃ crystal does not substantially exist in the grain boundary of the zirconia crystal, so that the reactivity with lead is low and the bending strength is high. In other words, the presence of spinel at the grain boundaries of cubic zirconia suppresses precipitation at the grain boundaries of Al ₂ O ₃ crystals that react with lead, reducing the reactivity with lead, and filling the grain boundaries with spinel. Therefore, the bending strength is increased. Further, by making the amount of the stabilizer 20 mol% or more, cubic zirconia undergoes phase transformation, and it is possible to more effectively suppress the generation of tetragonal zirconia and monoclinic zirconia that easily react with the lead component. And the reaction with PZT can be reduced. Further, since the total amount of stabilizer is below 43 mol%, cubic zirconia, can prevent the crystals other than MgO · _Al 2 _{O 3} is deposited, cubic zirconia, and MgO · _Al 2 _{O 3} other than It can suppress that a crystal reacts with PZT.

  The reaction preventing member for the lead-containing compound of the present invention will be described with reference to the accompanying drawings, taking as an example a firing jig for firing lead zirconate titanate (hereinafter referred to as PZT).

  The firing jig in the present invention means a jig used when firing a molded body, and examples include a setter for placing the molded body when firing and a firing bowl for placing the molded body and a setter. it can. In other words, a member that is in direct contact with the molded body, such as a setter, or that reacts or may react with lead vapor evaporated from the molded body, such as a firing bowl, is referred to as a firing jig.

FIG. 1 shows an embodiment in which a reaction preventing member for a lead-containing compound of the present invention is used as a firing jig. FIG. 1A is a longitudinal sectional view of the firing jig, and FIG. 1B is a perspective view of the firing jig.

  The firing jig using the reaction-preventing member for the lead-containing compound of the present invention is used for firing a powder molded body such as a metal, alloy, or ceramic containing lead inserted therein, as shown in FIG. 1) As shown in FIG. 1B, the support plate 101, the spacer 102 having the through-hole 107 and the top plate 103 are combined to form a space 104 inside, and come into contact with the main surface of the support plate 101. In addition, the molded body 105 is placed in the space 104, and the firing jig is placed in the firing furnace together with the molded body 105 for firing.

  Since the space 104 is separated from the external space, lead volatilized from the molded body 105 can be prevented from going out of the firing jig, and the amount of lead volatilized from the molded body 105 can be reduced. By reducing the gaps between the firing jigs of the support plate 101, the spacer 102, and the top plate 103, the amount of lead that volatilizes can be further reduced. Note that the weight body 106 may be placed on the molded body 105 so as to contact the main surface of the molded body 105. Hereinafter, a case where lead zirconate titanate (hereinafter referred to as PZT) is fired as the lead-containing compound as the molded body 105 will be described as an example.

The anti-reaction member for PZT of the present invention is composed of a zirconia sintered body having cubic zirconia as the main crystal phase, spinel is present at the grain boundaries of the zirconia crystal, and substantially no Al ₂ O ₃ crystal is present. is important. The main reaction between the zirconia sintered body and PZT is that a part of the additive added to the zirconia sintered body is precipitated at the grain boundary and reacts with PZT. The Al ₂ O ₃ crystal added to the zirconia sintered body to increase the strength and improve the strength is precipitated at the grain boundary and reacts with the lead component. Therefore, the presence of spinel at the grain boundaries of the zirconia crystal suppresses the precipitation of Al ₂ O ₃ crystals that react with PZT into the grain boundaries, lowers the reactivity with PZT, and reduces MgO · Al _2. O ₃ improves the bond strength at the grain boundaries and increases the bending strength of the zirconia sintered body.

Spinel is a zirconia sintered body processed into a 0.1 μm thin sample by FIB, the grain boundary part (particularly the triple point part) of the sample is observed by TEM, and the crystal phase is obtained by electron diffraction. This can be confirmed by identification. Also, the fact that Al ₂ O ₃ crystals are not substantially present at the grain boundaries means that the diffraction images are not observed by electron diffraction as observed with TEM.

In addition, since MgO works as a stabilizer for zirconia, even if the Mg component is separated from the spinel at the grain boundaries, the solid solute is dissolved in the zirconia crystal and the degree of stabilization of cubic zirconia is improved. In addition, spinel has a wide solid solution region on the Al ₂ O ₃ excess composition side, and even if the Mg component is separated from the spinel at the grain boundary, the Al component remains in the spinel, and Al ₂ O ₃ crystals are precipitated at the grain boundary. The low reactivity to PZT is kept low.

  In the reaction preventing member for PZT of the present invention, the amount of spinel is preferably 0.1 to 1.0% by mass, particularly 0.1 to 0.5% by mass of the reaction preventing material. By increasing the spinel to more than 0.1% by mass, the amount of cubic zirconia bound at the grain boundary of the spinel increases, and the bending strength of the reaction preventing member can be increased to 200 MPa or more. Thereby, the reaction preventing member can be used as a firing setter for multistage firing having a thickness of about 0.5 mm. Moreover, the reactivity with PZT can be made lower by making the quantity of spinel less than 1.0 mass%.

The amount of spinel is 0.1 to 1.0% by mass of the reaction inhibitor, and the amount of Al ₂ O ₃ added is about 0.1 to 1 mol%.

  As for the amount of spinel, since Al does not form a solid solution in the zirconia crystal, it is confirmed by TEM electron diffraction that there is no diffraction image of a crystal containing Al other than spinel at the grain boundary of the zirconia crystal. What is necessary is just to measure the amount of Al contained in the aggregate by fluorescent X-ray analysis and convert it to the amount of spinel.

  Furthermore, the bending strength in the present invention is a three-point bending measurement according to JIS R1601, but when a test piece having the dimensions defined in JIS R1601 cannot be produced from the measurement object, the length is measured. What is necessary is just to cut out a rectangular parallelepiped or a cylinder from a measuring object so that the difference between the dimension of a part and the defined dimension may become a test piece.

Further, the reaction preventing member for the lead-containing compound of the present invention has the above composition, and is composed of a zirconia sintered body having cubic zirconia as a main crystal phase. The zirconia has a crystal structure of cubic, monoclinic, tetragonal. Can take crystals. Among these, monoclinic crystals are easy to react with PbO and cause PbZrO ₃ to be generated, so it is better not to be included as a reaction preventing member. Tetragonal crystals also have a lot of room for solid solution of the substance in zirconia and cause reaction with Pb, so that the crystal phase is preferably only cubic. By using cubic zirconia as the main crystal, the effect of suppressing the solid solution of additives and impurities in zirconia and suppressing the reaction with Pb can be achieved.

On the other hand, since the cubic crystal is a high-temperature stable phase, the reactivity with PbO is low, and it is important that it is contained in the reaction preventing member for the lead-containing compound, and it is necessary to be contained as the main crystal phase. In particular, the zirconia sintered body having the following cubic ratio _Xc represented by diffraction intensity by X-ray diffraction of 0.97 or more can further reduce the reactivity with lead, and the reaction to lead-containing compounds. It is suitable as a prevention member, and when used as a firing jig, it is possible to obtain a sintered body with small variations in characteristics such as piezoelectric characteristics.

In particular, the cubic ratio _Xc of the zirconia sintered body is preferably 0.98 or more, and more preferably 0.99 or more in order to further reduce the reactivity with lead. Zirconia becomes a high-temperature stable phase in the order of monoclinic, tetragonal and cubic crystals.

The cubic ratio _Xc in the present invention can be calculated from the spectrum analysis by X-ray diffraction analysis using the following formulas 1 and 2.

  In addition, it is preferable that there is substantially no monoclinic peak. The fact that the X-ray diffraction intensity here is substantially absent means that the intensity is 0.1 or less when the XRD main peak intensity is 100.

For example, FIG. 2 shows the X-ray diffraction spectrum of the reaction preventing member for the lead-containing compound of the present invention, where the horizontal axis is 2θ and the vertical axis is the X-ray diffraction intensity. According to this figure, X _m = 0 and X _c = 1.0 are obtained. Thus, when the cubic ratio _Xc is 0.97 or more, it becomes possible to remarkably suppress the reaction with a lead-containing compound such as PZT, and the reaction preventing member of the present invention is used as a firing jig. In this case, the piezoelectric characteristic variation on the surface of the fired sintered body can be reduced, and furthermore, the piezoelectric characteristic variation can be reduced between the firing lots even when used repeatedly.

FIG. 3 shows the X-ray diffraction spectrum of the reaction preventing member outside the range of the present invention. According to this figure, X _m = 0.039 and X _c = 0.716 are obtained. As described above, when the cubic ratio _Xc is smaller than 0.97, a reaction with an orthorhombic crystal, a grain boundary crystal phase, or the like occurs, and a reaction with the formed body occurs at the time of sintering.

2 and 3 are measured in the range of 2θ of 10 to 80 °, but in calculating _Xc , the region near the peak of the corresponding surface is set to a narrow step width. It is preferable to perform a precise measurement with a longer sampling time in each step and calculate using an enlarged peak (not shown) near the peak.

  Furthermore, the firing jig of the present invention preferably has no precipitation other than zirconia crystals and spinel. Here, the absence of crystal precipitation means that the diffraction peak intensity is 0.1 or less when the cubic zirconia main peak intensity is 100 by XRD analysis, and the magnification is 3000 times using FE-SEM. This means that no precipitated phase is observed when scanning with.

Moreover, it is preferable not to contain Si substantially. The reason is that SiO ₂ easily reacts with PbO and generates a liquid phase at an extremely low temperature of 1000 ° C. or less.

In the present invention, “substantially free of Si” means that Si is 200 ppm or less in terms of silica (SiO ₂ ).

  The stabilizer added to the zirconia sintered body is preferably dissolved in the zirconia crystal of the zirconia sintered body to almost the solid solution limit. Thereby, while stabilizing a zirconia crystal | crystallization more, crystal phases other than a cubic crystal can be decreased easily, and the reactivity with respect to a lead containing compound can further be improved.

  The solid solution ratio in the zirconia crystal can be confirmed by measurement called lead belt crystal structure analysis. That is, when the lead belt crystal structure analysis is performed based on the X-ray diffraction data and the numerical value of the lattice constant is calculated, if the amount of solid solution increases and the solid solution reaches the solid solution limit, the amount of additional elements is further increased. Even so, the lattice constant is constant. Therefore, “near the solid solution limit” means a state having a value slightly smaller than the maximum value of the lattice constant.

In this case, the stabilizer does not have to be one kind. For example, CaO and Y ₂ O ₃ may be added in combination, and the ratio of CaO and Y ₂ O ₃ may be changed. As the stabilizer, in addition to CaO and Y ₂ O ₃ , rare earth elements other than La, such as Er, Sm, Dy, Nd, Yb, Lu, and Tb may be used.

The total amount of stabilizer added to the zirconia sintered body is preferably 20 to 43 mol%, particularly 25 to 40 mol%. This is the same whether a single stabilizer is added or a composite addition in which multiple stabilizers are added. By making the total amount of the stabilizer 20 mol% or more, cubic zirconia undergoes phase transformation, and tetragonal zirconia that easily reacts with the lead component and monoclinic zirconia can be more effectively suppressed, The reaction with PZT can be reduced. Further, since the total amount of stabilizer is below 43 mol%, cubic zirconia, can prevent the crystals other than MgO · _Al 2 _{O 3} is deposited, cubic zirconia, and MgO · _Al 2 _{O 3} other than It can suppress that a crystal reacts with PZT.

  The average crystal particle diameter of the zirconia sintered body is preferably 10 to 40 μm, particularly 25 to 38 μm, and more preferably 30 to 35 μm. As a result, even when repeatedly exposed to high temperatures, creep deformation is unlikely to occur, and thinning is facilitated. Further, the strength can be further increased by setting the average crystal particle diameter to 40 μm or less. The average crystal particle size was measured using a scanning electron microscope (SEM).

  The zirconia sintered body as described above can be suitably used as a reaction preventing member for a lead-containing compound, and particularly when a heat treatment is performed under conditions such as a Pb atmosphere or a high temperature of 600 ° C. or higher, Therefore, it can be suitably used as a heat treatment jig having a mounting surface for mounting a lead-containing compound. By using such a firing jig, it is possible to easily produce a homogeneously baked PZT porcelain.

  In particular, when a thin molded body containing lead for producing a piezoelectric ceramic and having a thickness of several hundred μm or less is fired, it is molded even if it is placed on the placing surface of the firing jig and subjected to heat treatment. Since there is substantially no reaction between the body and the firing jig, the piezoelectric ceramic obtained by firing can produce a sintered body with very little warping and waviness.

  It goes without saying that the reaction preventing member for the lead-containing compound of the present invention can be suitably used not only for a firing jig but also for a heat treatment jig used for heat treatment at 600 ° C. or higher, particularly 700 ° C. or higher, and further 800 ° C. or higher. For example, in heat treatment such as annealing treatment of lead-containing compounds, reaction treatment such as oxidation and reduction, and bonding treatment, the non-treated material is placed on a setter so as to come into contact with the non-treated material containing the lead-containing compound. In the case where the non-processed material is sandwiched between the pair of flat plate reaction preventing members, the influence of lead which is a volatile element from the non-processed material can be reduced during the heat treatment. Can suppress surface composition fluctuations after heat treatment.

  In particular, a common electrode and a piezoelectric layer are laminated in this order on the vibration plate, a plurality of surface electrodes are formed on the piezoelectric layer, a surface electrode, a common electrode facing the surface electrode, and these electrodes Even if heat treatment is performed on an actuator for a print head of an ink jet printer in which a plurality of piezoelectric displacement elements composed of piezoelectric layers sandwiched between them are formed, variation in displacement between the plurality of piezoelectric elements can be easily controlled. In addition, it is possible to suppress variation in displacement between heat treatment lots of a plurality of times.

  A method for producing a reaction preventing member for the lead-containing compound of the present invention will be described below.

  First, raw material powder is prepared. As the zirconia powder, it is preferable to use zirconia powder made of cubic zirconia.

  It is preferable to use a zirconia powder having an average particle size of about 0.1 to 1 μm.

For the addition of the CaO component, CaO powder may be used directly, but CaO may be formed by heat treatment of Ca hydroxide, carbonate or nitrate. The CaO powder is preferably about 0.3 to 1 μm. _Further, Y 2 _{O 3} powder is preferably used having an average particle size of about 0.1 to 1 [mu] m.

For the addition of the MgO component, MgO powder may be used directly, but MgO may be formed by heat treatment of Mg hydroxide, carbonate or nitrate. The MgO powder is preferably about 0.5 to 2 μm. In addition, it is preferable to use Al ₂ O ₃ powder having an average particle size of about 0.2 to ₂ μm. Further, spinel may be added to add the MgO component and the Al ₂ O ₃ component. In this case, Al component contained as an impurity in the zirconia material or the like, because the spinel is a wide solid solution region Al ₂ O ₃ excessive composition side, taken in added pressure spinel Runode grain zirconia crystals precipitation of Al ₂ O ₃ crystals in the field can be suppressed.

The above zirconia powder, additive powder, an organic solvent such as isopropyl alcohol, and zirconia balls are put into a resin pot, mixed and pulverized. The obtained mixed powder is heat-treated to produce a synthetic powder containing zirconia, MgO, Al ₂ O ₃ , CaO and Y ₂ O ₃ . For example, the mixed powder can be heat-treated at 1000 to 1400 ° C.

  The obtained synthetic powder is pulverized using zirconia balls until the average particle size is about 0.3 to 0.8 μm. An organic binder and a solvent are mixed with the pulverized raw material powder to produce a slurry, and a green sheet is produced from the obtained slurry by a known molding method such as tape molding, casting molding or injection molding. The obtained green sheet is cut into a desired size, and a plurality of green sheets cut as desired are laminated to produce a molded body. The slurry may be dried to produce a dry raw material, and a molded body having a desired shape may be produced from the dry raw material by a method such as press molding.

  The obtained molded body is degreased at a desired temperature, for example, 300 to 500 ° C., and then fired at a desired temperature, for example, 1200 to 1700 ° C., particularly 1300 to 1600 ° C., to obtain a reaction preventing member. it can.

  A reaction preventing member for a lead-containing compound was prepared.

As starting materials, ZrO ₂ having a crystallization rate of 0.95 or more, stabilizers shown in Table 1, additives shown in Table 1, isopropyl alcohol, and zirconia balls having a diameter of 2 mm are put into a resin pot. And mixing and grinding for 16 hours. Thereafter, the powder was put in an alumina crucible having a purity of 99.9%, and subjected to heat treatment at 1200 ° C. for 2 hours to produce a synthetic powder. The synthetic powder was pulverized for 20 hours using a zirconia ball having a diameter of 2 mm, and 5 wt% of paraffin wax was mixed with the obtained powder, followed by granulation through a # 40 nylon mesh. After granulation, it was press-molded to 30 mm × 20 mm × 0.6 mm. The molded body was debindered at 400 ° C. for 2 hours, and then fired in the atmosphere at the firing temperature shown in Table 1 for 2 hours to form a reaction preventing member made of a zirconia sintered body having a thickness of 0.5 mm. Obtained.

The reaction preventing member for the obtained lead-containing compound was subjected to composition analysis by fluorescent X-ray analysis. For quantitative analysis, a calibration curve using ZrO ₂ , MgO, Al ₂ O ₃ , CaO, and Y ₂ O ₃ was prepared in advance, and the calibration curve was used.

  The crystal grain size of the zirconia sintered body was measured using a scanning electron microscope (SEM).

  Moreover, about the reaction prevention member used by the following reaction test, surface processing was performed so that surface roughness Ra might be set to 0.01-0.05.

  Next, the reaction preventing member for the prepared lead-containing compound was evaluated.

  A piezoelectric ceramic powder containing lead zirconate titanate having a purity of 99% or more was prepared as a raw material for the lead-containing compound.

  The green sheet is a piezoelectric ceramic material powder mainly composed of lead zirconate titanate, water-soluble by adding a functional group to butyl methacrylate as an aqueous binder, polycarboxylic acid ammonium salt as a dispersant, Isopropyl alcohol and pure water were added and mixed as solvents to prepare a slurry, and this slurry was formed into a sheet shape having a thickness of about 30 μm on a carrier film by a doctor blade method.

  Similarly, green sheets were prepared using various piezoelectric ceramic powders. Also, an internal electrode paste was prepared. The obtained internal electrode paste was printed on the surface of the green sheet with a thickness of 4 μm to form an internal electrode. Furthermore, one green sheet on which the internal electrode paste was not printed was laminated between two sheets of green sheets with the surface on which the internal electrodes were printed facing upward, and pressed to obtain a laminated molded body.

  After debinding by holding the reaction test laminate molded body at 400 ° C. in the atmosphere for 2 hours, as shown in FIG. 1, the reaction test laminate compact is placed on a firing jig having the composition shown in Table 1. Placed. Specifically, the support plate 101, the spacer 102, and the top plate 103 are combined to form a space 104 therein, and the reaction test laminate molding is performed in the sealed space 104 so as to contact the main surface of the support plate 101. The body 105 was placed, and the weight body 107 was placed on the reaction test laminated molded body.

  After degreasing the laminated molded body, the laminated molded body was placed in a firing furnace so as to be sandwiched between reaction preventing members having the compositions shown in Table 1. This was held for 2 hours in an atmosphere of 900 ° C. and oxygen 99% or more and fired to produce a laminate composed of a piezoelectric vibration layer and internal electrodes.

  This was held for 2 hours in an atmosphere of the temperature shown in Table 1 and oxygen of 99% or more and fired to produce a laminate composed of a piezoelectric vibration layer and internal electrodes.

The X-ray diffraction spectrum of the setter surface used for firing was evaluated, and _Xc was calculated using the above formulas 1 and 2.

  The presence or absence of a grain boundary precipitated phase was also confirmed by X-ray diffraction spectrum and FE-SEM.

Further, in the case where there is no crystal phase containing Al other than spinel in the grain boundary part of the zirconia crystal by electron beam diffraction of TEM, the amount of Al contained in the zirconia sintered body is measured by fluorescent X-ray analysis, and spinel ( It was calculated in terms of the amount of (MgO.Al ₂ O ₃ crystal).

Next, the presence or absence of a reaction layer was confirmed after firing 1, 5, 10, 50, 100, and 500 times. In addition, the presence or absence of the reaction layer is detected by conducting surface analysis with a scanning electron microscope (SEM) and EDS on the surface of the reaction preventing member in contact with the lead-containing compound, and if detected, ×, not detected When it was, it was displayed as ○. The results are shown in Table 1.

Sample No. of the present invention. In Nos. 1 to 27, 30 and 31, MgO.Al ₂ O ₃ crystals are precipitated at the grain boundaries of the zirconia crystals, and Al ₂ O ₃ crystals are not substantially precipitated. The reaction phase could not be observed, and the reaction with the laminated molded body was suppressed. Sample No. 1 containing 0.1 to 1% by mass of MgO.Al ₂ O ₃ crystals was obtained. 2 to 27, 30 and 31 had a bending strength of 200 MPa or more.

On the other hand, the sample No. 5 outside the scope of the present invention in which Al ₂ O ₃ crystals were precipitated at the grain boundaries of the zirconia crystals. In Nos. 28 and 29, a reaction phase was observed on a part of the setter surface in the first firing.

It is a baking jig | tool using the reaction prevention member with respect to the lead containing compound of this invention, (a) is a longitudinal cross-sectional view, (b) is a perspective view. It is a figure which shows the X-ray-diffraction spectrum of the reaction prevention member of this invention. It is a figure which shows the X-ray-diffraction spectrum of the reaction prevention member outside the range of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Support plate 102 ... Spacer 103 ... Top plate 104 ... Space 105 ... Molded body 106 ... Weight body 107 ... Through-hole

Claims (5)

Cubic zirconia as a main crystal phase, consist distearate zirconia sintered body to contain 20～43Mol% of stabilizer, with the spinel is present in grain boundaries of the zirconia crystals of the zirconia sintered body, substantially A reaction preventing member for a lead-containing compound, characterized in that no Al ₂ O ₃ crystal is present. The reaction preventing member for a lead-containing compound according to claim 1, wherein the zirconia sintered body does not substantially contain Si. The reaction preventing member for a lead-containing compound according to claim 1 or 2, wherein the spinel is contained in an amount of 0.1 to 1% by mass and the bending strength is 200 MPa or more. The cubic structure ratio _Xc of the zirconia sintered body represented by the following formulas 1 and 2 is 0.97 or more, and the reaction preventing member for a lead-containing compound according to any one of claims 1 to 3 .
The reaction preventing material for a lead-containing compound according to any one of claims 1 to 4 , wherein the zirconia sintered body has an average crystal particle diameter of 10 to 40 µm.