JP2017170725A - Paste for the space formation of ceramic component, method for filling the same and method for producing ceramic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paste for the space formation of a ceramic component suitable for discharge at a dispenser.SOLUTION: Provided is a paste 98 for the space formation of a ceramic component includes: a lost form material; a resin; a solvent; and a plasticizer, in which viscosity at 25°C is 500 to 4,500 Pa s, and also the ratio of the solvent occupied in the whole is 6 to 17 vol%. It is preferable that a green sheet 204 having an opening part 243 is made into a state of being mounted on a green sheet 203 (fig.(c)), the paste 98 for space formation is discharged using a dispenser 90, and is filled into the opening part 243 (fig.(d),(e)) to dry the paste 98 for space formation (fig.(f)).SELECTED DRAWING: Figure 2

Description

  The present invention relates to a ceramic component space forming paste, a filling method thereof, and a ceramic component manufacturing method.

  Conventionally, as a method of manufacturing a ceramic component such as a sensor element, a method is known in which a plurality of ceramic green sheets are prepared, a predetermined wiring pattern is formed on them, the layers are laminated, and the obtained laminate is sintered. It has been. In addition, when forming a space inside such a ceramic component, it is known that a punched portion is formed in a ceramic green sheet by punching, and an internal space forming member is embedded in the punched portion (for example, Patent Documents). 1). The internal space forming member is formed of a sublimable material that sublimes during firing, and the embedded portion of the internal space forming member becomes a space after firing. As a method of embedding the internal space forming member in the punched portion of the ceramic green sheet, it is known to use a sheet of the internal space forming member formed by a doctor blade method or screen printing (for example, Patent Documents 1 and 2). . Patent Document 2 describes a method in which a sheet piece of a predetermined size is punched and molded from a sheet of an internal space forming member, and the obtained sheet piece is adsorbed by a suction disk and embedded in a punched portion. As another method, a green sheet in which a punched portion is formed is placed on a set table, and a sheet of an internal space forming member is disposed thereon, and a punch having the same planar shape as the punched portion is placed on the sheet. A method of lowering is also described. In this method, a process of punching a sheet with a punch and a process of filling a punched sheet piece into a punched part are continuously performed.

Patent No. 5296131 Japanese Patent No. 3153143

  However, when a sheet piece is punched and molded from the sheet of the internal space forming member as in Patent Document 2, there is a problem that a portion of the sheet that has not been punched becomes a waste loss. In order to solve this problem, instead of using the sheet of the internal space forming member, it is considered that the paste for forming the internal space is discharged using a dispenser (liquid fixed amount discharge device) to fill the punched portion. It is done. However, no paste suitable for such use has been known.

  The present invention has been made to solve such problems, and a main object of the present invention is to provide a ceramic component space forming paste suitable for discharging with a dispenser.

  The present invention employs the following means in order to achieve the main object described above.

The ceramic component space forming paste of the present invention is:
Including a disappearing material, a resin, a solvent, and a plasticizer, the viscosity at 25 ° C. is 500 Pa · s or more and 4500 Pa · s or less, and the ratio of the solvent in the whole is 6 vol% or more and 17 vol% or less. ,
Is.

The space forming paste filling method of the present invention includes:
(A) a step of placing a ceramic green sheet having an opening on a predetermined substrate;
(B) discharging the space forming paste of the ceramic component of the present invention described above using a dispenser to fill the opening;
(C) drying the filled space forming paste;
Is included.

The method for producing the ceramic component of the present invention comprises:
A preparation step of preparing three or more ceramic green sheets;
An opening forming step of forming an opening in one or more of the three or more ceramic green sheets;
Filling the space forming paste into the opening by performing the above-described space forming paste filling method of the present invention on at least one of the ceramic green sheets in which the opening is formed;
A laminating step of laminating and pressing the three or more ceramic green sheets including the ceramic green sheet so that the ceramic green sheet after the filling step is sandwiched; and
A firing step of firing the laminate;
Is included.

  The paste for forming a space of the ceramic component of the present invention has a viscosity of 500 Pa · s or more, so that excessive discharge when discharged from the dispenser can be suppressed. Moreover, it can suppress that a viscosity is too high and it becomes impossible to discharge from a dispenser because a viscosity is 4500 Pa.s or less. Moreover, precipitation of resin in the paste for space formation is reduced and the clogging of a dispenser can be suppressed because the ratio of a solvent is 6 volume% or more. From the foregoing, the ceramic component space forming paste of the present invention is suitable for discharging with a dispenser. Moreover, the space forming paste of the ceramic component of the present invention has a drying shrinkage rate of 17% by volume or less because the solvent ratio is 17% by volume or less. When the drying shrinkage rate is 17% or less, it can be suppressed that the space forming paste shrinks too much and the filling of the opening of the ceramic green sheet becomes insufficient after drying. Therefore, the paste for forming a space of the present invention is suitable for forming a space of a ceramic part. Further, in the method for filling the space forming paste of the present invention and the method for manufacturing the ceramic component of the present invention, the space forming paste of the ceramic component of the present invention described above is used to fill the opening, and then dried. Therefore, the same effect as described above can be obtained. Moreover, in the filling method of the space forming paste of the present invention and the ceramic component manufacturing method of the present invention, the space forming paste is used to fill the opening with a dispenser. For example, the space forming paste is punched from the space forming sheet. Compared with the case where the sheet piece is embedded in the opening, the waste loss can be reduced.

FIG. 3 is a schematic cross-sectional view schematically showing an example of the configuration of the gas sensor 100. Explanatory drawing of the manufacturing process of the sensor element 101. FIG. Explanatory drawing of the manufacturing process of the sensor element 101. FIG.

  Next, embodiments of the present invention will be described with reference to the drawings. First, the sensor element 101 which is one embodiment of the ceramic component will be described. FIG. 1 is a schematic cross-sectional view schematically illustrating an example of a configuration of a gas sensor 100 including a sensor element 101. The sensor element 101 has a long rectangular parallelepiped shape. The longitudinal direction (the left-right direction in FIG. 1) of the sensor element 101 is the front-rear direction, and the thickness direction of the sensor element 101 (up-down direction in FIG. 1) is the up-down direction. The direction. The width direction of sensor element 101 (the direction perpendicular to the front-rear direction and the up-down direction) is the left-right direction.

The sensor element 101 includes a first substrate layer 1, a second substrate layer 2, a third substrate layer 3, and a first solid electrolyte layer 4 each made of an oxygen ion conductive solid electrolyte layer such as zirconia (ZrO ₂ ). The spacer layer 5 and the second solid electrolyte layer 6 are elements having a structure in which the layers are laminated in this order from the bottom in the drawing. The solid electrolyte forming these six layers is dense and airtight. The sensor element 101 is manufactured, for example, by performing predetermined processing and circuit pattern printing on a ceramic green sheet corresponding to each layer, stacking them, and firing and integrating them.

  One end of the sensor element 101, and between the lower surface of the second solid electrolyte layer 6 and the upper surface of the first solid electrolyte layer 4, is a gas inlet 10, a first diffusion rate limiting unit 11, and a buffer space. 12, the second diffusion rate limiting part 13, the first internal space 20, the third diffusion rate limiting part 30, and the second internal space 40 are adjacently formed in such a manner that they communicate in this order.

  The gas introduction port 10, the buffer space 12, the first internal space 20, and the second internal space 40 are provided on the lower surface of the second solid electrolyte layer 6 with the upper portion provided in a state in which the spacer layer 5 is cut out. The space inside the sensor element 101 is defined by the lower part being the upper surface of the first solid electrolyte layer 4 and the side parts being the side surfaces of the spacer layer 5.

  Each of the first diffusion rate controlling unit 11, the second diffusion rate controlling unit 13, and the third diffusion rate controlling unit 30 is provided as two horizontally long slits (the opening has a longitudinal direction in a direction perpendicular to the drawing). . In addition, the site | part from the gas inlet 10 to the 2nd internal space 40 is also called a gas distribution part.

  Further, at a position farther from the front end side than the gas circulation part, the side part is partitioned by the side surface of the first solid electrolyte layer 4 between the upper surface of the third substrate layer 3 and the lower surface of the spacer layer 5. The reference gas introduction space 43 is provided at the position. For example, the atmosphere is introduced into the reference gas introduction space 43 as a reference gas when measuring the NOx concentration.

  The air introduction layer 48 is a layer made of porous ceramics, and a reference gas is introduced into the air introduction layer 48 through the reference gas introduction space 43. The air introduction layer 48 is formed so as to cover the reference electrode 42.

  The reference electrode 42 is an electrode formed in such a manner that it is sandwiched between the upper surface of the third substrate layer 3 and the first solid electrolyte layer 4. As described above, the reference electrode 42 leads to the reference gas introduction space 43. An air introduction layer 48 is provided. Further, as will be described later, it is possible to measure the oxygen concentration (oxygen partial pressure) in the first internal space 20 and the second internal space 40 using the reference electrode 42.

  In the gas circulation part, the gas inlet 10 is a part opened to the external space, and the gas to be measured is taken into the sensor element 101 from the external space through the gas inlet 10. The first diffusion control unit 11 is a part that provides a predetermined diffusion resistance to the gas to be measured taken from the gas inlet 10. The buffer space 12 is a space provided to guide the gas to be measured introduced from the first diffusion rate controlling unit 11 to the second diffusion rate controlling unit 13. The second diffusion rate limiting unit 13 is a part that imparts a predetermined diffusion resistance to the gas to be measured introduced from the buffer space 12 into the first internal space 20. When the gas to be measured is introduced from the outside of the sensor element 101 to the inside of the first internal space 20, the pressure fluctuation of the gas to be measured in the external space (exhaust pressure pulsation if the gas to be measured is an automobile exhaust gas) ), The gas to be measured that is suddenly taken into the sensor element 101 from the gas inlet 10 is not directly introduced into the first internal space 20, but the first diffusion control unit 11, the buffer space 12, the second After the concentration variation of the gas to be measured is canceled through the diffusion control unit 13, the gas is introduced into the first internal space 20. As a result, the concentration fluctuation of the gas to be measured introduced into the first internal space 20 becomes almost negligible. The first internal space 20 is provided as a space for adjusting the partial pressure of oxygen in the gas to be measured introduced through the second diffusion rate limiting unit 13. The oxygen partial pressure is adjusted by the operation of the main pump cell 21.

  The main pump cell 21 includes an inner pump electrode 22 having a ceiling electrode portion 22a provided on substantially the entire lower surface of the second solid electrolyte layer 6 facing the first internal space 20, and an upper surface of the second solid electrolyte layer 6. An electrochemical pump cell comprising an outer pump electrode 23 provided in a manner exposed to the external space in a region corresponding to the ceiling electrode portion 22a, and a second solid electrolyte layer 6 sandwiched between these electrodes. is there.

  The inner pump electrode 22 is formed across the upper and lower solid electrolyte layers (the second solid electrolyte layer 6 and the first solid electrolyte layer 4) that define the first inner space 20, and the spacer layer 5 that provides side walls. Yes. Specifically, a ceiling electrode portion 22a is formed on the lower surface of the second solid electrolyte layer 6 that provides the ceiling surface of the first internal space 20, and a bottom portion is formed on the upper surface of the first solid electrolyte layer 4 that provides the bottom surface. Spacer layers in which the electrode portions 22b are formed and the side electrode portions (not shown) constitute both side walls of the first internal space 20 so as to connect the ceiling electrode portions 22a and the bottom electrode portions 22b. 5 is formed on the side wall surface (inner surface), and is disposed in a tunnel-shaped structure at the portion where the side electrode portion is disposed.

The inner pump electrode 22 and the outer pump electrode 23 are formed as a porous cermet electrode (for example, a cermet electrode of Pt and ZrO ₂ containing 1% of Au). The inner pump electrode 22 in contact with the gas to be measured is formed using a material that has a reduced reduction ability for the NOx component in the gas to be measured.

  In the main pump cell 21, a desired pump voltage Vp 0 is applied between the inner pump electrode 22 and the outer pump electrode 23, and the pump current is positive or negative between the inner pump electrode 22 and the outer pump electrode 23. By flowing Ip0, oxygen in the first internal space 20 can be pumped into the external space, or oxygen in the external space can be pumped into the first internal space 20.

  Further, in order to detect the oxygen concentration (oxygen partial pressure) in the atmosphere in the first internal space 20, the inner pump electrode 22, the second solid electrolyte layer 6, the spacer layer 5, and the first solid electrolyte layer 4. The third substrate layer 3 and the reference electrode 42 constitute an electrochemical sensor cell, that is, a main pump control oxygen partial pressure detection sensor cell 80.

  By measuring the electromotive force V0 in the main pump control oxygen partial pressure detection sensor cell 80, the oxygen concentration (oxygen partial pressure) in the first internal space 20 can be known. Further, the pump current Ip0 is controlled by feedback controlling the pump voltage Vp0 of the variable power source 24 so that the electromotive force V0 is constant. Thereby, the oxygen concentration in the first internal space 20 can be kept at a predetermined constant value.

  The third diffusion control unit 30 provides a predetermined diffusion resistance to the gas under measurement whose oxygen concentration (oxygen partial pressure) is controlled by the operation of the main pump cell 21 in the first internal space 20, and the gas under measurement is supplied to the gas under measurement. This is the part that leads to the second internal space 40.

  The second internal space 40 is provided as a space for performing a process related to the measurement of the nitrogen oxide (NOx) concentration in the gas to be measured introduced through the third diffusion control unit 30. The NOx concentration is measured mainly in the second internal space 40 in which the oxygen concentration is adjusted by the auxiliary pump cell 50, and further by measuring the pump cell 41 for measurement.

  In the second internal space 40, after the oxygen concentration (oxygen partial pressure) is adjusted in advance in the first internal space 20, the auxiliary pump cell 50 is further supplied to the gas to be measured introduced through the third diffusion control unit 30. The oxygen partial pressure is adjusted by the above. Thereby, since the oxygen concentration in the second internal space 40 can be kept constant with high accuracy, the gas sensor 100 can measure the NOx concentration with high accuracy.

  The auxiliary pump cell 50 includes an auxiliary pump electrode 51 having a ceiling electrode portion 51a provided on substantially the entire lower surface of the second solid electrolyte layer 6 facing the second internal space 40, and an outer pump electrode 23 (outer pump electrode 23). The auxiliary electrochemical pump cell is configured by the second solid electrolyte layer 6 and a suitable electrode outside the sensor element 101 is sufficient.

  The auxiliary pump electrode 51 is disposed in the second internal space 40 in the same tunnel configuration as the inner pump electrode 22 provided in the first internal space 20. That is, the ceiling electrode portion 51 a is formed on the second solid electrolyte layer 6 that provides the ceiling surface of the second internal space 40, and the first solid electrolyte layer 4 that provides the bottom surface of the second internal space 40 is formed on the first solid electrolyte layer 4. The bottom electrode part 51b is formed, and the side electrode part (not shown) connecting the ceiling electrode part 51a and the bottom electrode part 51b is provided on the spacer layer 5 that provides the side wall of the second internal space 40. It has a tunnel-type structure formed on both wall surfaces. Note that the auxiliary pump electrode 51 is also formed using a material having a reduced reducing ability with respect to the NOx component in the gas to be measured, like the inner pump electrode 22.

  In the auxiliary pump cell 50, by applying a desired voltage Vp1 between the auxiliary pump electrode 51 and the outer pump electrode 23, oxygen in the atmosphere in the second internal space 40 is pumped to the external space, or It is possible to pump into the second internal space 40 from the space.

  Further, in order to control the oxygen partial pressure in the atmosphere in the second internal space 40, the auxiliary pump electrode 51, the reference electrode 42, the second solid electrolyte layer 6, the spacer layer 5, and the first solid electrolyte. The layer 4 and the third substrate layer 3 constitute an electrochemical sensor cell, that is, an auxiliary pump control oxygen partial pressure detection sensor cell 81.

  The auxiliary pump cell 50 performs pumping by the variable power source 52 that is voltage-controlled based on the electromotive force V1 detected by the auxiliary pump control oxygen partial pressure detection sensor cell 81. Thereby, the oxygen partial pressure in the atmosphere in the second internal space 40 is controlled to a low partial pressure that does not substantially affect the measurement of NOx.

  At the same time, the pump current Ip1 is used to control the electromotive force of the oxygen partial pressure detection sensor cell 80 for main pump control. Specifically, the pump current Ip1 is input as a control signal to the main pump control oxygen partial pressure detection sensor cell 80, and the electromotive force V0 is controlled, so that the third diffusion rate limiting unit 30 controls the second internal space. The gradient of the oxygen partial pressure in the gas to be measured introduced into the gas 40 is controlled so as to be always constant. When used as a NOx sensor, the oxygen concentration in the second internal space 40 is maintained at a constant value of about 0.001 ppm by the action of the main pump cell 21 and the auxiliary pump cell 50.

  The measurement pump cell 41 measures the NOx concentration in the gas to be measured in the second internal space 40. The measurement pump cell 41 includes a measurement electrode 44 provided on a top surface of the first solid electrolyte layer 4 facing the second internal space 40 and spaced from the third diffusion rate-determining portion 30, an outer pump electrode 23, The electrochemical pump cell is constituted by the second solid electrolyte layer 6, the spacer layer 5, and the first solid electrolyte layer 4.

  The measurement electrode 44 is a porous cermet electrode. The measurement electrode 44 also functions as a NOx reduction catalyst that reduces NOx present in the atmosphere in the second internal space 40. Further, the measurement electrode 44 is covered with a fourth diffusion rate controlling part 45.

  The 4th diffusion control part 45 is a film | membrane comprised with a ceramic porous body. The fourth diffusion control unit 45 plays a role of limiting the amount of NOx flowing into the measurement electrode 44 and also functions as a protective film for the measurement electrode 44. In the measurement pump cell 41, oxygen generated by the decomposition of nitrogen oxides in the atmosphere around the measurement electrode 44 can be pumped out, and the generated amount can be detected as the pump current Ip2.

  In order to detect the oxygen partial pressure around the measurement electrode 44, an electrochemical sensor cell, that is, a first solid electrolyte layer 4, a third substrate layer 3, a measurement electrode 44, and a reference electrode 42, that is, A measurement pump control oxygen partial pressure detection sensor cell 82 is configured. The variable power supply 46 is controlled on the basis of the electromotive force V2 detected by the measurement pump control oxygen partial pressure detection sensor cell 82.

The gas to be measured introduced into the second internal space 40 reaches the measurement electrode 44 through the fourth diffusion rate-determining unit 45 under the condition where the oxygen partial pressure is controlled. Nitrogen oxide in the gas to be measured around the measurement electrode 44 is reduced (2NO → N ₂ + O ₂ ) to generate oxygen. The generated oxygen is pumped by the measurement pump cell 41. At this time, the variable power source is set so that the electromotive force V2 detected by the measurement pump control oxygen partial pressure detection sensor cell 82 is constant. 46 voltage Vp2 is controlled. Since the amount of oxygen generated around the measurement electrode 44 is proportional to the concentration of nitrogen oxide in the gas to be measured, the nitrogen oxide in the gas to be measured using the pump current Ip2 in the measurement pump cell 41. The concentration will be calculated.

  If the measurement electrode 44, the first solid electrolyte layer 4, the third substrate layer 3, and the reference electrode 42 are combined to form an oxygen partial pressure detecting means as an electrochemical sensor cell, the measurement electrode The electromotive force according to the difference between the amount of oxygen generated by the reduction of the NOx component in the atmosphere around 44 and the amount of oxygen contained in the reference atmosphere can be detected, whereby the NOx component in the gas to be measured It is also possible to determine the concentration of.

  The second solid electrolyte layer 6, the spacer layer 5, the first solid electrolyte layer 4, the third substrate layer 3, the outer pump electrode 23, and the reference electrode 42 constitute an electrochemical sensor cell 83. The oxygen partial pressure in the gas to be measured outside the sensor can be detected by the electromotive force Vref obtained by the sensor cell 83.

  In the gas sensor 100 having such a configuration, by operating the main pump cell 21 and the auxiliary pump cell 50, the oxygen partial pressure is always kept at a constant low value (a value that does not substantially affect the measurement of NOx). A gas to be measured is supplied to the measurement pump cell 41. Therefore, the NOx concentration in the measurement gas is determined based on the pump current Ip2 that flows when oxygen generated by the reduction of NOx is pumped out of the measurement pump cell 41 in proportion to the NOx concentration in the measurement gas. You can know.

  Furthermore, the sensor element 101 includes a heater unit 70 that plays a role of temperature adjustment for heating and maintaining the sensor element 101 in order to increase the oxygen ion conductivity of the solid electrolyte. The heater unit 70 includes a heater connector electrode 71, a heater 72, a through hole 73, a heater insulating layer 74, and a pressure dissipation hole 75.

  The heater connector electrode 71 is an electrode formed so as to be in contact with the lower surface of the first substrate layer 1. By connecting the heater connector electrode 71 to an external power source, power can be supplied to the heater unit 70 from the outside.

  The heater 72 is an electric resistor formed in a form sandwiched between the second substrate layer 2 and the third substrate layer 3 from above and below. The heater 72 is connected to the heater connector electrode 71 through the through-hole 73, and generates heat when power is supplied from the outside through the heater connector electrode 71, thereby heating and keeping the solid electrolyte forming the sensor element 101. .

  The heater 72 is embedded over the entire area from the first internal space 20 to the second internal space 40, and the entire sensor element 101 can be adjusted to a temperature at which the solid electrolyte is activated. ing.

  The heater insulating layer 74 is an insulating layer formed on the upper and lower surfaces of the heater 72 by an insulator such as alumina. The heater insulating layer 74 is formed for the purpose of obtaining electrical insulation between the second substrate layer 2 and the heater 72 and electrical insulation between the third substrate layer 3 and the heater 72.

  The pressure dissipating hole 75 is a portion that is provided so as to penetrate the third substrate layer 3 and communicate with the reference gas introduction space 43, and is for the purpose of alleviating the increase in internal pressure accompanying the temperature increase in the heater insulating layer 74. Formed.

  Next, a method for manufacturing the sensor element 101 configured as described above will be described below. 2 and 3 are explanatory diagrams of the manufacturing process of the sensor element 101. FIG. 2 and 3 mainly show how the reference gas introduction space 43 and the pressure diffusion hole 75 as the internal space of the sensor element 101 are formed. Hereinafter, the ceramic green sheet is simply referred to as a green sheet.

The manufacturing method of the sensor element 101 of this embodiment is as follows:
A preparation step of preparing three or more green sheets;
An opening forming step of forming an opening in one or more of the three or more green sheets;
For at least one of the green sheets in which the opening is formed, a filling step of filling the opening with a space-forming paste;
A lamination step in which three or more ceramic green sheets including the ceramic green sheet are laminated and pressed to form a laminate so that the ceramic green sheets after the filling step are sandwiched;
A firing step of firing the laminate;
Is included.

[Preparation process]
In the preparation step, three or more green sheets are prepared. In this embodiment, a plurality of green sheets whose main component is ceramics (zirconia in this embodiment), which is a solid electrolyte having oxygen ion conductivity, are prepared. In the present embodiment, the sensor element 101 includes six layers of first to third substrate layers 1 to 3, a first solid electrolyte layer 4, a spacer layer 5, and a second solid electrolyte layer 6. Therefore, six green sheets 201 to 206 (see FIGS. 2A and 3C described later) corresponding to each layer are prepared. In the preparation step, green sheets 201 to 206 prepared in advance may be prepared, or may be prepared by preparing green sheets 201 to 206. When the green sheets 201 to 206 are produced, for example, a stabilized zirconia powder, an organic binder, and an organic solvent are mixed to form a paste, and this paste is used to produce the paste.

[Opening Step]
In the opening forming step, an opening is formed in one or more of the prepared green sheets 201 to 206. The opening is formed by a green sheet in which the corresponding layer has a space. In the present embodiment, the green sheet 204 corresponding to the first solid electrolyte layer 4 having the reference gas introduction space 43, the green sheet 203 corresponding to the third substrate layer 3 having the pressure diffusion hole 75, the buffer space 12, and the first Openings are respectively formed in the green sheet 205 corresponding to the spacer layer 5 having the first and second internal cavities 20 and 40. The opening is formed, for example, by punching using a punch of a press. 2A, the green sheet 204 in which a rectangular opening 243 corresponding to the reference gas introduction space 43 is formed, the green sheet 203 in which the opening 275 corresponding to the pressure dissipation hole 75 is formed, Is shown in cross section.

  In the present embodiment, the plurality of sensor elements 101 are manufactured together. Therefore, each of the green sheets 201 to 206 includes a plurality of regions that become corresponding layers in the sensor element 101 after firing. Accordingly, in the opening forming step, for example, a plurality of openings 275 are formed in the green sheet 204.

  A hole corresponding to the through hole 73 is also formed in the green sheets 201 and 202 corresponding to the first and second substrate layers 1 and 2 having the through hole 73. Moreover, you may form the hole used for positioning of the several green sheet at the time of lamination | stacking. These holes may be formed in the opening forming step, or before and after that.

[Pattern formation process]
In the present embodiment, after the opening forming process, the pattern forming process is performed before the filling process. In the pattern forming step, a predetermined pattern made of a paste is formed and dried on one or more of the three or more green sheets (green sheets 201 to 206 in the present embodiment) prepared in the preparation step. Specifically, the pattern is a pattern for forming each electrode, lead wire, heater, and the like of the sensor element 101. Each pattern is formed by applying a pattern forming paste prepared according to the characteristics required for each forming object to a green sheet corresponding to the layer on which the forming object is to be formed. The pattern may be formed by screen printing, for example. About the drying process after formation, a well-known drying technique can be utilized, for example, it is common to carry out in the air atmosphere at the temperature of 75-90 degreeC, for example. FIG. 2B shows a state in which the pre-firing air introduction layer 248 that is a pattern that becomes the air introduction layer 48 after firing is formed on the upper surface of the green sheet 203.

[Filling process]
After the opening forming step and the pattern forming step, in the filling step, the space forming paste is filled into the opening of at least one of the green sheets on which the opening is formed. The space forming paste filling method performed in the filling step is as follows:
(A) a step of placing a green sheet having an opening on a predetermined substrate;
(B) discharging the space forming paste using a dispenser and filling the openings;
(C) drying the filled space-forming paste;
including.

  Hereinafter, the case where the opening 243 and the opening 275 are filled with the space forming paste 98 in the filling step will be described with reference to FIGS. 2 (c) to 2 (f) and FIGS. 3 (a) and 3 (b). First, in step (a), the green sheet 204 having the opening 275 is placed on a predetermined base. In this embodiment, the green sheet 203 is used as the base of the green sheet 204 to be filled, and the green sheet 204 is placed on the green sheet 203 (FIG. 2C). Note that the first solid electrolyte layer 4 to which the green sheet 204 corresponds and the third substrate layer 3 to which the green sheet 203 corresponds are adjacent to each other in the sensor element 101, and the green sheet 203, 204 needs to be adjacently stacked (see FIG. 3C described later). Therefore, in the present embodiment, the green sheets 203 and 204 whose corresponding layers are adjacent to each other are stacked in advance, and one of them is used as the other base. When the green sheets 203 and 204 are laminated, an adhesive paste pattern (not shown) is previously formed on at least one of the two. Then, the green sheets 203 and 204 are laminated and bonded through the bonding paste.

  Subsequently, in step (b), the space forming paste 98 is discharged using the dispenser 90 to fill the opening 243 (FIG. 2D). Here, the space forming paste 98 will be described. The space forming paste 98 includes an extinguishing material, a resin, a solvent, and a plasticizer. The viscosity at 25 ° C. is 500 Pa · s to 4500 Pa · s, and the proportion of the solvent in the whole is 6% by volume. The content is 17% by volume or less.

  As the extinguishing material, a material that disappears (for example, sublimates) by a baking process described later can be used. Examples of the disappearing material include polymer beads such as activated carbon and melamine resin, caffeine, indigo, hexabromobenzene, naphthacene, or theobromine, and two or more of these may be used in combination. The disappearing material is preferably hardly soluble in an organic solvent (such as ether) used for the green sheet. In this embodiment, the disappearing material is theobromine.

  Examples of the resin include ethyl cellulose and polyvinyl butyral, and these may be mixed and used. In this embodiment, the resin is polyvinyl butyral. The resin plays a role of adjusting the viscosity of the space forming paste 98 together with the solvent and the plasticizer.

  Examples of the solvent include 2-ethylhexanol, butyl carbitol, butyl carbitol acetate, terpineol, hydrogenated terpineol, and the like, and two or more of these may be used as a mixture. In this embodiment, the solvent was 2-ethylhexanol.

  Examples of the plasticizer include dioctyl phthalate and dibutyl phthalate, and these may be used in combination. In this embodiment, the plasticizer is dioctyl phthalate.

  The space forming paste 98 may or may not contain a dispersant. When a dispersant is blended, a part of the plasticizer is replaced with the dispersant. As the dispersant, a dispersant generally used in ceramic paste can be used, and two or more such dispersants may be mixed and used.

  The space forming paste 98 is prepared by mixing raw materials including the above-described disappearable material, a resin, a solvent, and a plasticizer. The mixing can be performed, for example, using a raw material such as a pot mill, a ball mill, a bead mill, a trommel, a planetary mill, an attritor, a triroll mill, or a revolving stirrer. In addition, the space forming paste 98 has a viscosity of 500 Pa · s to 4500 Pa · s at 25 ° C., and the proportion of the solvent in the whole is 6% by volume to 17% by volume. Adjust and mix. For example, the proportion of the disappearing material in the space forming paste 98 may be 25 wt% or more and 80 wt% or less, and preferably 50 wt% or more and 65 wt% or less. The proportion of the resin in the entire space forming paste 98 may be 1 wt% or more and 20 wt% or less, and is preferably 1.7 wt% or more and 5.5 wt% or less. The ratio of the solvent in the entire space forming paste 98 may be 5 wt% or more and 13 wt% or less. The total proportion of the plasticizer and the dispersing agent in the entire space forming paste 98 may be 2 wt% or more and 50 wt% or less, and preferably 20 wt% or more and 35 wt% or less (however, the plasticizer is 2 wt% or more, The dispersant is 0 wt% or more). By satisfying 1 or more of these numerical ranges, the viscosity at 25 ° C. of the space forming paste 98 can be made 500 Pa · s or more and 4500 Pa · s or less relatively easily. Further, the disappearing material is, for example, in a powder form, and the average particle size may be 1 μm or more and 40 μm or less. In addition, an average particle diameter shall mean the median diameter (D50) measured using the laser beam diffraction method.

  The dispenser 90 for discharging the space forming paste 98 is a jet dispenser in this embodiment. As shown in FIG. 2 (d), the dispenser 90 includes a storage chamber forming member 91, a liquid agent path 94, a piston 95, and a spring 96. The storage chamber forming member 91 has a storage chamber 92 that is an internal space, and a discharge port 93 that opens downward as an outlet of the space forming paste 98 from the storage chamber 92. The liquid agent path 94 is a space serving as a path for the space forming paste 98 to the storage chamber 92. The liquid agent path 94 is connected to a supply source (not shown), and the space forming paste 98 is supplied to the storage chamber 92 via the liquid agent path 94 by a pressure such as air. The piston 95 seals the discharge port 93 at the normal position and seals the upper portion of the storage chamber 92, and the member that opens and closes the discharge port 93 while increasing and decreasing the volume of the storage chamber 92 by moving up and down. It is. The piston 95 is urged downward by the elastic force of the spring 96 disposed between the storage chamber forming member 91. The piston 95 moves upward against the urging force of the spring 96 by power from a power source such as a piezoelectric actuator (not shown). When the piston 95 moves upward from the normal position, the volume of the storage chamber 92 increases in accordance with the movement amount, and the space forming paste 98 in the storage chamber 92 is lowered from the discharge port 93 by the pressure from the liquid agent path 94 side. Discharged. Thereafter, when the piston 95 is lowered by the elastic force of the spring 96, the piston 95 causes the space forming paste 98 in the storage chamber 92 to be completely discharged from the discharge port 93, and then the piston 95 returns to the normal position to thereby discharge the discharge port 93. Is sealed. A period until the piston 95 moves upward from the normal position and returns to the normal position is referred to as a discharge cycle. The dispenser 90 continuously discharges the space forming paste 98 from the discharge port 93 by repeating this discharge cycle.

  In step (b), the dispenser 90 is used to fill the opening 243 with the space forming paste 98. Specifically, a space is continuously formed from the discharge port 93 of the dispenser 90 in a discharge cycle of a predetermined time while moving at least one of the work (here, the green sheets 204 and 203) and the dispenser 90 by a moving mechanism (not shown). The paste 98 for discharging is discharged, and the space forming paste 98 is filled in the openings 243 (FIGS. 2D and 2E). Relative moving speed between the workpiece and the dispenser 90, the diameter of the discharge port 93, the pressure and temperature of the space forming paste 98 supplied from the liquid agent path 94, the time required for one discharge cycle, the repetition interval of the discharge cycle (discharge cycle) The filling conditions such as the time from the start of the first discharge cycle to the start of the next discharge cycle) may be appropriately determined according to the shape of the opening 243 (front / rear / left / right size and upper / lower height). For example, as the height of the opening 243 is deeper (as the necessary space forming paste 98 is thicker), the discharge amount of the space forming paste 98 is increased or the viscosity of the space forming paste 98 is increased. The filling condition may be set so as to increase or decrease the relative movement distance during one discharge cycle. In this embodiment, the green sheet 203 used as a base has an opening 275 that communicates with the opening 243. In such a case, as shown in FIG. 2D, the space is formed once so that the diameter of the droplet of the space forming paste 98 discharged at one time is larger than the opening area of the opening 275. It is preferable to adjust the discharge amount of the paste 98 for use. This makes it easy to fill the space forming paste 98 in the upper portion of the opening 275 in the opening 243. In addition, it is preferable to set the filling condition so that the filling of the opening 243 is completed while the dispenser 90 moves relatively back and forth and right and left above the opening 243 and performs one scan. In consideration of the amount of shrinkage of the space forming paste 98 due to drying, the space forming paste 98 exists above the upper surface of the green sheet 204 (the upper opening surface of the opening 243). 98 fillings may be performed.

  The space forming paste 98 has a viscosity at 25 ° C. of 500 Pa · s or more, so that excessive discharge when discharged from the dispenser 90 can be suppressed. Further, the space forming paste 98 has a viscosity of 4500 Pa · s or less, so that it is possible to prevent the viscosity from being too high to be discharged from the dispenser 98. In addition, since the space forming paste 98 has a solvent ratio of 6% by volume or more, precipitation of the resin in the space forming paste 98 is reduced, and clogging of the dispenser 90 can be suppressed. From the above, the space forming paste 98 is suitable for discharging with the dispenser 90.

  In step (b), it is preferable that the temperature of the space forming paste 98 to be discharged exceeds 20 ° C. with respect to the temperature of the space forming paste 98 supplied from the liquid agent path 94 among the filling conditions described above. More preferably, it is 30 ° C. or higher. By setting the space forming paste 98 to exceed 20 ° C., it is possible to suppress, for example, the viscosity of the space forming paste 98 from becoming high and the discharge amount per time (one drop) from becoming insufficient. By setting the space forming paste 98 to 30 ° C. or higher, the heat treatment for drying in step (c) can be eliminated. In step (b), the temperature of the discharged space forming paste 98 is preferably less than 90 ° C., more preferably 80 ° C. or less. By setting the space forming paste 98 to less than 90 ° C., for example, it is possible to suppress the viscosity of the space forming paste 98 from being lowered and the discharge amount per time (one drop) from being excessive. By setting the space forming paste 98 to 80 ° C. or less, the resin in the space forming paste 98 is hardly denatured.

  Next, in step (c), the filled space forming paste 98 is dried. As a result, the solvent is removed from the space forming paste 98 to form the space forming member 243a (FIG. 2F). The drying is performed by bringing the space forming paste 98 to a state of 30 ° C. or higher and 80 ° C. or lower, for example. In addition, when the space forming paste 98 discharged in step (b) is set to 30 ° C. or more, the space forming paste 98 after filling may be naturally dried without performing the heat treatment. In this way, the space forming paste 98 can be used as the space forming member 243a without performing the heat treatment in step (c). When the space forming paste 98 is set to less than 30 ° C. in step (b), the space forming paste 98 filled in the space forming member 243a in step (c) may be heated to 30 ° C. or higher.

  Note that the volume of the space forming member 243a is reduced (shrinked) by the amount of the solvent reduced by drying from the space forming paste 98 after filling. Since the ratio of the solvent in the space forming paste 98 is 6% by volume to 17% by volume, the drying shrinkage rate of the space forming member 243a (the space forming paste 98 after drying) is 6% by volume to 17%. It is below volume%. When the drying shrinkage rate is 17% by volume or less, it can be suppressed that the space forming paste 98 is excessively contracted and the space forming member 243a is insufficiently filled after drying. That is, it can be suppressed that the volume of the space forming member 243a is insufficient with respect to the volume of the space forming member 243a.

  In the filling step, by performing steps (a) to (c) as described above, the opening 243 is filled with the space forming paste 98 (space forming member 243a). In the filling process of the present embodiment, the steps (a) to (c) are similarly performed on the other openings to fill the space forming paste 98. For example, the space forming paste 98 is filled into the opening 275 as follows. First, in step (a), the green sheets 203 and 204 in FIG. 2F are turned upside down so that the green sheet 203 having the opening 275 is placed on the green sheet 204 as a base. (FIG. 3A). Subsequently, in step (b), the space forming paste 98 is discharged using the dispenser 90 to fill the opening 275, and in step (c), the space forming paste 98 is dried to form the space forming member 275a ( FIG. 3 (b)). Although not shown, the steps (a) to (c) are similarly performed on the green sheet 205 corresponding to the spacer layer 5 in the opening corresponding to the buffer space 12 and the first and second internal spaces 20 and 40. The space forming paste 98 is filled. In the filling step, at least one of the material, blending ratio, and filling conditions of each raw material of the space forming paste 98 may be varied according to the opening to be filled. For example, when filling the opening 275 with the space forming paste 98, compared to filling the opening 243 with the space forming paste 98, the droplets of the space forming paste 98 that are discharged at one time are reduced. It is preferable to vary the filling conditions so that the diameter is reduced.

[Lamination process]
In the laminating step, three or more green sheets 201 to 206 prepared in the preparatory step including the green sheets are laminated and pressed to be laminated so that the green sheets after filling (green sheets 203 to 205 in this case) are sandwiched. Let it be the body. Since the space forming members 243a and 275a are members corresponding to the internal space of the sensor element 101, each of the green sheets 203 and 204 filled with the space forming members 243a and 275a is sandwiched between other green sheets from above and below. To be in a state. That is, the green sheets 203 and 204 are not positioned at the uppermost layer or the lowermost layer of the stack. The same applies to the green sheet 205 filled with a space forming member (not shown). In this lamination process, first, a pattern of an adhesive paste is formed on the green sheets 201 to 206 as in the step (a) of the filling process described above. Subsequently, the green sheets 201 to 206 are stacked so as to be stacked in this order, and are pressed by applying a predetermined pressure at a predetermined temperature to form one stacked body (FIG. 3C). Specifically, for example, green sheets 201 to 206 to be stacked are stacked and held using a sheet hole or the like on a predetermined stacking jig (not shown) and stacked by a stacking machine such as a known hydraulic press machine. A laminated body is obtained by heating and pressurizing together with the jig. FIG. 3C shows the space forming members 243a and 275a and the periphery of the laminate, and the pre-firing heater 272 and the pre-firing heater insulating layer 274, which are patterns to become the heater 72 and the heater insulating layer 74 after firing, are also shown. Illustrated. For example, when the space forming members 243a and 275a do not exist in the openings 243 and 275 corresponding to the internal space of the sensor element 101, the shapes of the openings 243 and 275 are formed when the stacked green sheets 201 to 206 are pressed. May not be maintained, or in the green sheets 201 to 206, the pressure in the regions located above and below the openings 243 and 275 may be insufficient. By filling the openings 243 and 275 with the space forming members 243a and 275a, it is possible to suppress the occurrence of such a problem. Further, when the drying shrinkage rate at the time of drying the space forming paste 98 is too large, the openings 243 and 275 are not sufficiently filled with the space forming members 243a and 275a, so that the space forming members 243a and 275a are placed above and below the space forming members 243a and 275a. The above-mentioned problem may occur due to a gap. In this embodiment, when the drying shrinkage rate of the space forming paste 98 is 17% by volume or less, it is possible to further suppress the occurrence of such a problem. The same applies to the space forming paste 98 (space forming member) filled in the opening corresponding to the buffer space 12 and the first and second internal spaces 20, 40 of the green sheet 205.

[Cutout process]
In the present embodiment, after the stacking process, the cutting process is performed before the firing process. As described above, in the present embodiment, each of the green sheets 201 to 206 includes a plurality of regions that become corresponding layers in the sensor element 101 after firing. A plurality of unfired sensor elements are included. Therefore, in the cutting process, the stacked body is cut to cut out a plurality of unfired sensor elements.

[Baking process]
In the firing step, the plurality of unfired sensor elements (laminates) obtained in the cutting step are fired. Firing is performed, for example, at a firing temperature of 1350 to 1400 ° C. while adjusting so as to have a predetermined water vapor partial pressure in an air atmosphere. During this firing step, the space forming members 243a and 275a and the space forming member (not shown) filled in the green sheet 205 disappear, and the sensor element 101 is obtained (FIG. 3D).

  In the manufacturing method of the sensor element 101 of this embodiment described in detail above, the space forming paste 98 of the sensor element 101 has a viscosity at 25 ° C. of 500 Pa · s to 4500 Pa · s, and the ratio of the solvent in the whole is It is 6 vol% or more and 17 vol% or less. When the viscosity is 500 Pa · s or more, excessive discharge when discharging from the dispenser 90 can be suppressed. Moreover, it can suppress that a viscosity is too high and it becomes impossible to discharge from the dispenser 90 because a viscosity is 4500 Pa.s or less. Moreover, precipitation of the resin in the paste for space formation is reduced because the ratio of the solvent is 6% by volume or more, and clogging of the dispenser 90 can be suppressed. From the above, the space forming paste 98 is suitable for discharging with the dispenser 90. Further, the space forming paste 98 has a drying shrinkage rate of 17% by volume or less because the ratio of the solvent is 17% by volume or less, and the space forming paste 98 is contracted too much, so that the openings 243 and 275 are formed. It is possible to prevent the filling of the resin from becoming insufficient after drying. Therefore, the space forming paste 98 is suitable for forming the space of the sensor element 101.

  Further, as a ratio of each raw material in the entire space forming paste 98, the ratio of the disappearing material is 50 wt% or more and 65 wt% or less, or the ratio of the resin is 1.7 wt% or more and 5.5 wt% or less, It is relatively easy to satisfy at least one of the solvent ratio of 5 wt% to 13 wt% or the total ratio of the plasticizer and the dispersant to 20 wt% to 35 wt%. The viscosity at 25 ° C. of the space forming paste 98 can be 500 Pa · s or more and 4500 Pa · s or less.

  Further, in the filling step of the present embodiment, the openings 243 and 275 are filled by the dispenser 90 using the above-described space forming paste 98 and then dried. Therefore, for example, waste loss can be reduced as compared with a case where a sheet piece punched out from a space forming sheet is embedded in the opening. Moreover, it can suppress that the discharge amount of 1 time (1 drop) from the dispenser 90 becomes inadequate by making the space formation paste 98 discharged exceeding 20 degreeC. By setting the discharged space forming paste 98 to 30 ° C. or higher, the heat treatment for drying the filled space forming paste 98 can be made unnecessary. By setting the temperature of the discharged space forming paste 98 to less than 90 ° C., it is possible to suppress an excessive discharge amount (one drop) from the space forming paste 98. By setting the discharged space forming paste 98 to 80 ° C. or less, the resin in the space forming paste 98 is hardly denatured.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, the space forming paste 98 is discharged using the dispenser 90 configured as a jet dispenser, but is not limited to the jet dispenser. For example, not only a non-contact dispenser such as a jet dispenser, but a contact dispenser such as a screw dispenser or a monopump dispenser may be used. The space forming paste 98 of the above-described embodiment is suitable not only for jet dispenser but also for discharging with a dispenser. However, since it is not necessary to consider the undulation of the upper surface of the green sheet to be filled, it is preferable to use a non-contact type dispenser.

  In the above-described embodiment, when the space forming paste 98 is filled in the opening 243 of the green sheet 204, the green sheet 203 is used as a base, but the present invention is not limited thereto. For example, the green sheets 202 may be used as long as they are adjacently stacked in the stacking process, and the green sheet 202 may be used as the base of the green sheet 204. Alternatively, a member different from the green sheets stacked in the stacking step may be used as the base. In this case, in the filling process, after the space forming paste 98 is filled and dried, a step of peeling the base from the green sheet to be filled may be performed. As the base in this case, it is preferable to use a material that can be easily peeled off from the space forming paste 98 (space forming member) or the green sheet after drying. An example of the base in this case is a PET (polyethylene terephthalate) sheet.

  In the above-described embodiment, the pattern forming process is performed after the opening forming process and before the filling process, but the present invention is not limited thereto. What is necessary is just to perform a filling process after an opening part formation process, and the timing performed with a pattern formation process may be performed before an opening part formation process, for example, and may be performed after a filling process. Moreover, you may perform a pattern formation process in parallel with at least one of an opening part formation process and a filling process. Moreover, the timing for performing the pattern forming step may be divided into a plurality of timings. However, when using a green sheet that is laminated adjacently in the laminating process as a base in the filling process, at least a pattern to be formed between the green sheet to be filled and the green sheet that is the base, It must be formed before the filling process. On the other hand, when using a member other than the green sheet laminated in the laminating process as a base, there is no such limitation.

  In the embodiment described above, the laminated body includes a plurality of unfired sensor elements, but it is only necessary to include one or more unburned sensor elements. In addition, when the ceramic body such as the sensor element 101 can be obtained by firing the laminated body as it is, the cutting process may be omitted.

  In the above-described embodiment, the case of manufacturing the sensor element 101 that detects the specific gas concentration (NOx concentration, oxygen concentration, etc.) in the gas to be measured has been described. However, not only the sensor element 101 but also other ceramic parts are manufactured. The present invention may be applied. If there is no pattern to be formed in manufacturing the ceramic component, the pattern forming process may be omitted. Further, the present invention may be applied not only to the production of ceramic parts but also to a method for filling a space forming paste.

  Hereinafter, an example in which a space forming paste is specifically prepared and filled in the opening will be described as an example. In addition, this invention is not limited to a following example.

[Example 1]
In the manufacturing method of the sensor element 101 according to the above-described embodiment, the process up to the stacking process was performed to manufacture a stack, and Example 1 was obtained. In the preparation step, zirconia particles added with 4 mol% of a yttria stabilizer, an organic binder, and an organic solvent were mixed, and green sheets 201 to 206 were obtained by tape molding. The size of the opening 243 formed in the opening forming step was such that the left and right widths were 620 μm, the front and rear lengths were 73 mm, and the height (= the thickness of the green sheet 204) was 300 μm. The space forming paste 98 used in the filling step shows the disappearance material (theobromine), the resin (polyvinyl butyral), the solvent (2-ethylhexanol), and the plasticizer (dioctyl phthalate) shown in Table 1 below. The mixture was mixed at a blending ratio and mixed by a pot mill for 2.5 hours. When the viscosity at 25 ° C. of the space forming paste 98 was measured, it was 2500 Pa · s. The dispenser used in the filling process was PICO PV-100 (manufactured by Nordson Corporation). The filling conditions in the filling step are as follows: the moving speed of the workpiece (green sheets 204, 203) is 100 mm / sec, the diameter of the discharge port 93 is 0.012 inch, and the pressure for supplying the space forming paste 98 is 3.5 MPa. The temperature of the discharged space forming paste 98 was 60 ° C. The time required for one discharge cycle was 0.5 msec, and the repetition interval of the discharge cycle was 4 msec / time. Drying after filling was performed by natural drying until the temperature of the space forming paste 98 reached room temperature. The drying shrinkage rate of the space forming paste 98 (space forming member 243a) was 10% by volume. In the lamination step, green sheets 201 to 206 were laminated and pressed from above and below at a pressure of 1.26 kg / cm ^{2 to} obtain a laminate.

[Examples 2 to 4]
As shown in Table 1, the laminates of Examples 2 to 4 were the same as Example 1 except that the blending ratio of the resin and plasticizer in the space forming paste 98 was changed to change the viscosity at 25 ° C. Was made.

[Examples 5 and 6]
As shown in Table 1, Example 5 was carried out in the same manner as in Example 1 except that the mixing ratio of the solvent and the plasticizer in the space forming paste 98 was changed so that the drying shrinkage was 6% by volume and 17% by volume. , 6 were produced.

[Examples 7 and 8]
As shown in Table 1, the laminated bodies of Examples 7 and 8 were formed in the same manner as in Example 1 except that the temperature of the discharged space forming paste 98 (filling paste temperature) was 30 ° C. and 80 ° C. Produced.

[Comparative Example 1]
Comparative Example 1 was made in the same manner as in Example 1 except that the blending ratio of each raw material was changed so that the viscosity at 25 ° C. and the drying shrinkage rate of the space forming paste 98 were the values shown in Table 1. In Comparative Example 1, since the viscosity at 25 ° C. of the space forming paste 98 is too low at 20 Pa · s, the discharge amount from the dispenser 90 becomes excessive, and the space forming paste 98 overflows too much from the opening 243. , Could not be filled properly.

[Comparative Examples 2 and 3]
Comparative Examples 2 and 3 were made in the same manner as Example 1 except that the blending ratio of each raw material was changed so that the viscosity at 25 ° C. of the paste 98 for forming a space had the value shown in Table 1. In Comparative Example 2, since the viscosity at 25 ° C. of the space forming paste 98 was too low at 300 Pa · s, the discharge amount from the dispenser 90 was excessive as in Comparative Example 1, and could not be properly filled. In Comparative Example 3, the space forming paste 98 could not be discharged from the dispenser 90 because the viscosity at 25 ° C. was too high at 6500 Pa · s.

[Comparative Examples 4 and 5]
Laminates of Comparative Examples 4 and 5 were produced in the same manner as in Example 1 except that the blending ratio of each raw material was changed so that the drying shrinkage of the space forming paste 98 became the value shown in Table 1.

[Comparative Examples 6 and 7]
As shown in Table 1, Comparative Examples 6 and 7 were made in the same manner as in Example 1 except that the paste temperature during filling was 20 ° C. and 90 ° C. In Comparative Example 7, as in Comparative Examples 1 and 2, the discharge amount from the dispenser 90 was excessive and could not be filled properly. It is considered that the viscosity of the paste 98 for space formation at the time of discharge is too low because the paste temperature at the time of filling is 90 ° C.

[Evaluation of filling condition]
The laminates of Examples 1 to 8 and Comparative Examples 4 to 6 were cut in parallel to the vertical direction and the front-rear direction of FIG. 1 to cut the space forming member 243a and exposed to the cross section as shown in FIG. I let you. Then, by observing this cross section, the presence or absence of the upper and lower gaps of the space forming member 243a was examined, and when there was no gap, it was determined to be good.

  In Table 1, the mixing ratio of each raw material of each space forming paste 98 in Examples 1 to 8 and Comparative Examples 1 to 7, paste specification (viscosity and drying shrinkage at 25 ° C.), paste temperature at filling, and filling The evaluation result of a state is shown collectively. Table 1 shows the volume% in addition to the blending ratio (wt%) of the solvent. The viscosity is measured using MCR-102 (manufactured by Anton Paar), the viscosity range of 500 Pa · s or more is measured with φ8PP (parallel plate), and the viscosity range of less than 500 is measured with φ25CP ( (Cone plate).

  As can be seen from Table 1, Examples 1 to 8 in which the viscosity at 25 ° C. of the space-forming paste 98 is 500 Pa · s or more and 4500 Pa · s or less, and the proportion of the solvent in the whole is 6% by volume or more and 17% by volume or less. In any case, the space forming paste 98 could be appropriately filled in the opening 243 using the dispenser 90. Moreover, there were no voids above and below the space forming member 243a in the laminate, and good results were obtained. On the other hand, in Comparative Examples 1 and 2 using the space forming paste 98 having a viscosity at 25 ° C. of less than 500 Pa · s, it was excessively discharged and could not be properly filled. Further, in Comparative Example 3 using the space-forming paste 98 having a viscosity at 25 ° C. exceeding 4500 P · s, it was impossible to discharge and filling was impossible. In Comparative Examples 4 and 5 using the space forming paste 98 having a drying shrinkage rate exceeding 17%, a large gap was generated above and below the space forming member 243a in the laminate due to the large drying shrinkage rate. In Comparative Example 6 in which the paste temperature at the time of filling was 20 ° C., the discharge amount of the single space forming paste 98 from the dispenser 90 was insufficient, and the same filling conditions as in Examples 1 to 8 (the paste temperature at the time of filling was Except), the opening 243 could not be sufficiently filled. As a result, in Comparative Example 6, voids were formed above and below the space forming member 243a in the laminate. Therefore, it is considered that the paste temperature during filling is preferably over 20 ° C. In Comparative Example 7 in which the paste temperature during filling was 90 ° C., the viscosity of the space forming paste 98 was too low, and excessive discharge was caused under the same filling conditions as in Examples 1 to 8 (excluding the paste temperature during filling). . Therefore, it is considered that the paste temperature during filling is preferably less than 90 ° C.

  DESCRIPTION OF SYMBOLS 1 1st board | substrate layer, 2nd board | substrate layer, 3rd board | substrate layer, 4th 1st solid electrolyte layer, 5 spacer layer, 6 2nd solid electrolyte layer, 10 gas inlet, 11 1st diffusion control part, 12 buffer Space, 13 Second diffusion limiting part, 20 First internal space, 21 Main pump cell, 22 Inner pump electrode, 22a Ceiling electrode part, 22b Bottom electrode part, 23 Outer pump electrode, 24 Variable power supply, 30 Third diffusion limiting part , 40 2nd internal space, 41 Measurement pump cell, 42 Reference electrode, 43 Reference gas introduction space, 44 Measurement electrode, 45 4th diffusion control part, 46 Variable power supply, 48 Air introduction layer, 50 Auxiliary pump cell, 51 Auxiliary pump Electrode, 51a Ceiling electrode part, 51b Bottom electrode part, 52 Variable power supply, 70 Heater part, 71 Heater connector electrode, 72 Heater, 73 Through hole, 74 Heat Insulating layer, 75 pressure diffusion hole, 80 oxygen partial pressure detection sensor cell for main pump control, 81 oxygen partial pressure detection sensor cell for auxiliary pump control, 82 oxygen partial pressure detection sensor cell for measurement pump control, 83 sensor cell, 90 dispenser, 91 storage Chamber forming member, 92 storage chamber, 93 discharge port, 94 liquid agent path, 95 piston, 96 spring, 98 space forming paste, 100 gas sensor, 101 sensor element, 201-206 green sheet, 243 opening, 243a space forming member, 248 Air introduction layer before firing, 272 Heater before firing, 274 Heater insulation layer before firing, 275 opening, 275a space forming member.

Claims (10)

  Including a disappearing material, a resin, a solvent, and a plasticizer, the viscosity at 25 ° C. is 500 Pa · s or more and 4500 Pa · s or less, and the ratio of the solvent in the whole is 6 vol% or more and 17 vol% or less. , Paste for space formation of ceramic parts. The proportion of the disappearing material in the whole is 50 wt% or more and 65 wt% or less,
The paste for forming a space of a ceramic part according to claim 1. The proportion of the resin in the whole is 1.7 wt% or more and 5.5 wt% or less.
The paste for forming a space of a ceramic part according to claim 1 or 2. The proportion of the solvent in the whole is 5 wt% or more and 13 wt% or less,
The paste for space formation of the ceramic component of any one of Claims 1-3. It is the paste for space formation of the ceramic components of any one of Claims 1-4,
Containing 0 wt% or more dispersant,
The total proportion of the plasticizer and the dispersant in the whole is 20 wt% or more and 35 wt% or less,
Space forming paste for ceramic parts. (A) a step of placing a ceramic green sheet having an opening on a predetermined substrate;
(B) discharging the space forming paste of the ceramic component according to any one of claims 1 to 5 using a dispenser to fill the opening;
(C) drying the filled space forming paste;
A method of filling a paste for forming a space. In the step (b), the space forming paste having a temperature exceeding 20 ° C. and less than 90 ° C. is discharged.
The space forming paste filling method according to claim 6. In the step (b), the space forming paste at 30 ° C. or higher is discharged.
A method for filling the space forming paste according to claim 7. In the step (b), the space forming paste at 80 ° C. or lower is discharged.
The filling method of the space formation paste of Claim 7 or 8. A preparation step of preparing three or more ceramic green sheets;
An opening forming step of forming an opening in one or more of the three or more ceramic green sheets;
Filling at least one of the ceramic green sheets having the openings formed therein by filling the openings with the space forming paste according to any one of claims 6 to 9. Process,
A laminating step of laminating and pressing the three or more ceramic green sheets including the ceramic green sheet so that the ceramic green sheet after the filling step is sandwiched; and
A firing step of firing the laminate;
A method for manufacturing a ceramic part including:

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